Afzal, S, Daoud, WA & Langford, SJ 2014, 'Exploring the Use of Dye‐Sensitisation by Visible‐Light as New Approach to Self‐Cleaning Textiles', Journal of the Chinese Chemical Society, vol. 61, no. 7, pp. 757-762.
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AbstractPhotocatalytic degradation of organic contaminants by self‐cleaning textiles is an efficient method to create green environment and minimise energy consumption. In this work, the concept of dye‐sensitised self‐cleaning textiles has been introduced by incorporating monolayers of meso‐tetra(4‐carboxyphenyl)porphyrin (TCPP) on the surface of titania‐coated cotton against methylene blue. Different complexes of TCPP (M = 2H, Fe, Co, Zn, Cu) have been trialled and evaluated for photocatalytic activity and stability. Cotton fabrics coated with TCPP show superior photochemical activity as compared to TiO2‐coated fabrics under visible‐light irradiation. The free base derivative availed the highest photocatalytic efficiency when compared to the metal complexes with Cu∼Fe > Co > Zn. In terms of stability, meso‐tetra(4‐car‐boxyphenyl)porphyrinato copper(II) showed significant stabilisation under photocatalytic conditions when compared to the metal‐free porphyrin and other metal complexes (Cu ≫ Co > 2H > Zn∼Fe). Porphyrins offer great potential in visible‐light self‐cleaning applications.
Ahmed, M, Yajadda, MMA, Han, ZJ, Su, D, Wang, G, Ostrikov, KK & Ghanem, A 2014, 'Single-walled carbon nanotube-based polymer monoliths for the enantioselective nano-liquid chromatographic separation of racemic pharmaceuticals', Journal of Chromatography A, vol. 1360, pp. 100-109.
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Single-walled carbon nanotubes were encapsulated into different polymer-based monolithic backbones. The polymer monoliths were prepared via the copolymerization of 20% monomers, glycidyl methacrylate, 20% ethylene glycol dimethacrylate and 60% porogens (36% 1-propanol, 18% 1,4-butanediol) or 16.4% monomers (16% butyl methacrylate, 0.4% sulfopropyl methacrylate), 23.6% ethylene glycol dimethacrylate and 60% porogens (36% 1-propanol, 18% 1,4-butanediol) along with 6% single-walled carbon nanotubes aqueous suspension. The effect of single-walled carbon nanotubes on the chiral separation of twelve classes of pharmaceutical racemates namely; α- and β-blockers, antiinflammatory drugs, antifungal drugs, dopamine antagonists, norepinephrine-dopamine reuptake inhibitors, catecholamines, sedative hypnotics, diuretics, antihistaminics, anticancer drugs and antiarrhythmic drugs was investigated. The enantioselective separation was carried out under multimodal elution to explore the chiral recognition capabilities of single-walled carbon nanotubes using reversed phase, polar organic and normal phase chromatographic conditions using nano-liquid chromatography. Baseline separation was achieved for celiprolol, chlorpheniramine, etozoline, nomifensine and sulconazole under multimodal elution conditions. Satisfactory repeatability was achieved through run-to-run, column-to-column and batch-to-batch investigations. Our findings demonstrate that single-walled carbon nanotubes represent a promising stationary phase for the chiral separation and may open the field for a new class of chiral selectors. © 2014 .
Anantachaisilp, S, Smith, SM, Ton-That, C, Osotchan, T, Moon, AR & Phillips, MR 2014, 'Tailoring Deep Level Surface Defects in ZnO Nanorods for High Sensitivity Ammonia Gas Sensing', JOURNAL OF PHYSICAL CHEMISTRY C, vol. 118, no. 46, pp. 27150-27156.
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© 2014 American Chemical Society. The influence of deep level surface defects on electrical and gas sensing properties of ZnO nanorods NH3(g) sensors was studied. ZnO nanorods 50-60 nm in diameter were synthesized via low-temperature hydrothermal growth at 90°C on sapphire substrates. The as-grown nanorods exhibited a cathodoluminescence (CL) peak centered at 1.90 eV (YL), attributed to LiZn deep acceptors or O interstitials. Subsequent annealing in O2 at 1 atm and Zn vapor at 650°C produced broad CL peaks centered at 1.70 eV (RL) and 2.44 eV (GL), respectively. The RL and GL have been ascribed to acceptor-like VZn and donor-like VO related centers, respectively. Electrical and gas sensing measurements established that the NH3 gas response sensitivity was 22.6 for O2 anneal (RL), 1.4 for Zn vapor anneal (GL), and 4.1 for the as-grown (YL) samples. Additionally, treatment in H-plasma quenched the RL and inverted the NH3 electrical response due to the incorporation of H donors. Changes in the gas sensing response are explained by a shift in the position of the ZnO Fermi level relative to the chemical potential of NH3 gas due to the creation of near surface donor or acceptors. These data confirm that ZnO nanorods arrays can be tailored to detect specific gas species. (Chemical Equation Presented).
Butt, FK, Tahir, M, Cao, C, Idrees, F, Ahmed, R, Khan, WS, Ali, Z, Mahmood, N, Tanveer, M, Mahmood, A & Aslam, I 2014, 'Synthesis of Novel ZnV2O4 Hierarchical Nanospheres and Their Applications as Electrochemical Supercapacitor and Hydrogen Storage Material', ACS Applied Materials & Interfaces, vol. 6, no. 16, pp. 13635-13641.
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Callsen, G, Wagner, MR, Reparaz, JS, Nippert, F, Kure, T, Kalinowski, S, Hoffmann, A, Ford, MJ, Phillips, MR, Dalmau, RF, Schlesser, R, Collazo, R & Sitar, Z 2014, 'Phonon pressure coefficients and deformation potentials of wurtzite AlN determined by uniaxial pressure-dependent Raman measurements', PHYSICAL REVIEW B, vol. 90, no. 20.
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© 2014 American Physical Society. We studied bulk crystals of wurtzite AlN by means of uniaxial pressure-dependent Raman measurements. As a result, we derive the phonon pressure coefficients and deformation potentials for all zone center optical phonon modes. For the A1 and E1 modes, we further experimentally determined the uniaxial pressure dependence of their longitudinal optical-transverse optical (LO-TO) splittings. Our experimental approach delivers new insight into the large variance among previously reported phonon deformation potentials, which are predominantly based on heteroepitaxial growth of AlN and the ball-on-ring technique. Additionally, the measured phonon pressure coefficients are compared to their theoretical counterparts obtained by density functional theory implemented in the siesta package. Generally, we observe a good agreement between the calculated and measured phonon pressure coefficients but some particular Raman modes exhibit significant discrepancies similar to the case of wurtzite GaN and ZnO, clearly motivating the presented uniaxial pressure-dependent Raman measurements on bulk AlN crystals.
Canning, J, Huyang, G, Ma, M, Beavis, A, Bishop, D, Cook, K, McDonagh, A, Shi, D, Peng, G-D & Crossley, MJ 2014, 'Percolation Diffusion into Self-Assembled Mesoporous Silica Microfibres', NANOMATERIALS, vol. 4, no. 1, pp. 157-174.
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Percolation diffusion into long (11.5 cm) self-assembled, ordered mesoporous
microfibres is studied using optical transmission and laser ablation inductive
coupled mass spectrometry (LA-ICP-MS). Optical transmission based diffusion
studies reveal rapid penetration (< 5 s, D > 80 um2.s-1) of Rhodamine B with
very little percolation of larger molecules such as zinc tetraphenylporphyrin
(ZnTPP) observed under similar loading conditions. The failure of ZnTPP to
enter the microfibre was confirmed, in higher resolution, using LA-ICP-MS. In
the latter case, LA-ICP-MS was used to determine the diffusion of zinc acetate
dihydrate, D ~ 3 x 10-4 nm2.s-1. The large differences between the molecules
are accounted for by proposing ordered solvent and structure assisted
accelerated diffusion of the Rhodamine B based on its hydrophilicity relative
to the zinc compounds. The broader implications and applications for
filtration, molecular sieves and a range of devices and uses are described.
Chan, KS, Ton-That, C, Vines, L, Choi, S, Phillips, MR, Svensson, BG, Jagadish, C & Wong-Leung, J 2014, 'Effects of high temperature annealing on defects and luminescence properties in H implanted ZnO', JOURNAL OF PHYSICS D-APPLIED PHYSICS, vol. 47, no. 34, pp. 1-6.
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The evolution of luminescence properties and voids formation with respect to annealing temperature in H implanted ZnO was investigated by depth-resolved cathodoluminescence spectroscopy (DRCLS), transmission electron microscopy and secondary ion mass spectrometry (SIMS). The annealing temperature is found to induce noticeable changes to the shape, size and empty volume density of the cavities. DRCLS results also reveal that the green emission is influenced by different annealing temperatures. In particular, the 600 °C anneal produces a strong quenching of the green emission in the implanted region, while after the 800 °C anneal a significant enhancement near the surface is observed. The annealing at 600 °C also results in an uncommon violet emission at ∼3.1 eV that is not observed after a higher annealing temperature. A clear correlation between the violet emission, vacancies and Li is revealed from comparison between the DRCLS intensities and SIMS data. © 2014 IOP Publishing Ltd.
Chen, S, Bao, P, Huang, X, Sun, B & Wang, G 2014, 'Hierarchical 3D mesoporous silicon@graphene nanoarchitectures for lithium ion batteries with superior performance', NANO RESEARCH, vol. 7, no. 1, pp. 85-94.
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Silicon has been recognized as the most promising anode material for high capacity lithium ion batteries. However, large volume variations during charge and discharge result in pulverization of Si electrodes and fast capacity loss on cycling. This drawback of Si electrodes can be overcome by combination with well-organized graphene foam. In this work, hierarchical three-dimensional carbon-coated mesoporous Si nanospheres@graphene foam (C@Si@GF) nanoarchitectures were successfully synthesized by a thermal bubble ejection assisted chemical-vapor-deposition and magnesiothermic reduction method. The morphology and structure of the as-prepared nanocomposites were characterized by field emission scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. When employed as anode materials in lithium ion batteries, C@Si@GF nanocomposites exhibited superior electrochemical performance including a high specific capacity of 1,200 mAh/g at the current density of 1 A/g, excellent high rate capabilities and an outstanding cyclability. Post-mortem analyses identified that the morphology of 3D C@Si@GF electrodes after 200 cycles was well maintained. The synergistic effects arising from the combination of mesoporous Si nanospheres and graphene foam nanoarchitectures may address the intractable pulverization problem of Si electrode. [Figure not available: see fulltext.] © 2014 Tsinghua University Press and Springer-Verlag Berlin Heidelberg.
Chen, S, Huang, X, Liu, H, Sun, B, Yeoh, W, Li, K, Zhang, J & Wang, G 2014, '3D Hyperbranched Hollow Carbon Nanorod Architectures for High-Performance Lithium-Sulfur Batteries', ADVANCED ENERGY MATERIALS, vol. 4, no. 8, p. 1301761.
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Lithium-sulfur batteries have been plagued for a long time by low Coulombic efficiency, fast capacity loss, and poor high rate performance. Here, the synthesis of 3D hyperbranched hollow carbon nanorod encapsulated sulfur nanocomposites as cathode materials for lithium-sulfur batteries is reported. The sulfur nanocomposite cathodes deliver a high specific capacity of 1378 mAh g-1 at a 0.1C current rate and exhibit stable cycling performance. The as-prepared sulfur nanocomposites also achieve excellent high rate capacities and cyclability, such as 990 mAh g-1 at 1C, 861 mAh g -1 at 5C, and 663 mAh g-1 at 10C, extending to more than 500 cycles. The superior electrochemical performance are ascribed to the unique 3D hyperbranched hollow carbon nanorod architectures and high length/radius aspect ratio of the carbon nanorods, which can effectively prevent the dissolution of polysulfides, decrease self-discharge, and confine the volume expansion on cycling. High capacity, excellent high-rate performance, and long cycle life render the as-developed sulfur/carbon nanorod nanocomposites a promising cathode material for lithium-sulfur batteries. 3D hyperbranched carbon nanorod-sulfur nanocomposites are synthesized and applied as cathode materials for lithium-sulfur batteries. The composite materials deliver high specific capacity, excellent high rate capability, and extended cycle life. The superior performance is attributed to the nanomaze architecture and high aspect ratio of carbon nanorods, which suppress the dissolution of polysulfides and confine volume expansion. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Chen, S, Huang, X, Liu, H, Sun, B, Yeoh, W, Li, K, Zhang, J & Wang, G 2014, '3D Hyperbranched Hollow Carbon Nanorod Encapsulated Sulfur Composites for Lithium-Sulfur Batteries with Superior Electrochemical Performance', ECS Meeting Abstracts, vol. MA2014-04, no. 3, pp. 511-511.
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Lithium-sulfur batteries have been plagued for a long time by the low Coulombic efficiency, fast capacity loss and poor high rate performance. Herein, we report the synthesis of graphitic hyperbranched hollow carbon nanorods encapsulated sulfur composites as cathode materials for lithium-sulfur batteries. The sulfur composite cathodes, approximate 1 mg for each electrode, deliver a high specific capacity of 1378 mAh/g at 0.1C current rate and exhibit stable cycling performance. The as-prepared cathode materials also achieve excellent high rate capacities and cyclability, such as 990 mAh/g at 1C, 861 mAh/g at 5C and 663 mAh/g at 10C, extending to more than 500 cycles. The superior electrochemical performances could be ascribed to the unique graphitic hyperbranched hollow carbon nanorods architecture and high length/radius aspect ratio of carbon nanorods, which can effectively prevent the dissolution of polysulfides, decrease self-discharge and confine the volume expansion on cycling. High capacity, excellent high-rate performance and long cycle life render the as-developed sulfur/carbon nanorod composites as a promising cathode material for lithium-sulfur batteries.
Chen, S, Huang, X, Liu, H, Sun, B, Yeoh, W, Li, K, Zhang, J & Wang, G 2014, 'Batteries: 3D Hyperbranched Hollow Carbon Nanorod Architectures for High‐Performance Lithium‐Sulfur Batteries (Adv. Energy Mater. 8/2014)', Advanced Energy Materials, vol. 4, no. 8, pp. n/a-n/a.
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Chen, S, Huang, X, Sun, B, Zhang, J, Liu, H & Wang, G 2014, 'Multi-shelled hollow carbon nanospheres for lithium-sulfur batteries with superior performances', JOURNAL OF MATERIALS CHEMISTRY A, vol. 2, no. 38, pp. 16199-16207.
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© the Partner Organisations 2014. Lithium-sulfur batteries are regarded as a promising energy storage system. However, they are plagued by rapid capacity decay, low coulombic efficiency, a severe shuttle effect and low sulfur loading in cathodes. To address these problems, effective carriers are highly demanded to encapsulate sulfur and extend the cycle life. Here, we report an aqueous emulsion approach and in situ sulfur impregnation to synthesize multi-shelled hollow carbon nanosphere-encapsulated sulfur composites with a high percentage of sulfur loading (86 wt%). When applied as cathodes in lithium-sulfur batteries, the composite materials delivered a high specific capacity of 1350 mA h g-1and excellent capacity retention (92% for 200 cycles). Further measurements at high current densities also demonstrate significantly enhanced cyclability and high rate capability. This journal is
Chen, X, Liu, Y, Alexander, A, Gallucci, JC, Hwang, S, Lingam, HK, Huang, Z, Wang, C, Li, H, Zhao, Q, Ozkan, US, Shore, SG & Zhao, J 2014, 'Desolvation and Dehydrogenation of Solvated Magnesium Salts of Dodecahydrododecaborate: Relationship between Structure and Thermal Decomposition', Chemistry – A European Journal, vol. 20, no. 24, pp. 7325-7333.
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AbstractAttempts to synthesize solvent‐free MgB12H12 by heating various solvated forms (H2O, NH3, and CH3OH) of the salt failed because of the competition between desolvation and dehydrogenation. This competition has been studied by thermogravimetric analysis (TGA) and temperature‐programmed desorption (TPD). Products were characterized by IR, solution‐ and solid‐state NMR spectroscopy, elemental analysis, and single‐crystal or powder X‐ray diffraction analysis. For hydrated salts, thermal decomposition proceeded in three stages, loss of water to form first hexahydrated then trihydrated, and finally loss of water and hydrogen to form polyhydroxylated complexes. For partially ammoniated salts, two stages of thermal decomposition were observed as ammonia and hydrogen were released with weight loss first of 14 % and then 5.5 %. Thermal decomposition of methanolated salts proceeded through a single step with a total weight loss of 32 % with the release of methanol, methane, and hydrogen. All the gaseous products of thermal decomposition were characterized by using mass spectrometry. Residual solid materials were characterized by solid‐state 11B magic‐angle spinning (MAS) NMR spectroscopy and X‐ray powder diffraction analysis by which the molecular structures of hexahydrated and trihydrated complexes were solved. Both hydrogen and dihydrogen bonds were observed in structures of [Mg(H2O)6B12H12]⋅6 H2O and [Mg(CH3OH)6B12H12]⋅6 CH3OH, which were determined by single‐crystal X‐ray diffraction analysis. The structural factors influen...
Chen, XY, Jin, JX, Ying Xin, Guo, YG, Wei Xu, Wen, L & Zhu, JG 2014, 'Energy Exchange Experiments and Performance Evaluations Using an Equivalent Method for a SMES Prototype', IEEE Transactions on Applied Superconductivity, vol. 24, no. 5, pp. 1-5.
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Choi, S, Johnson, BC, Castelletto, S, Ton-That, C, Phillips, MR & Aharonovich, I 2014, 'Single photon emission from ZnO nanoparticles', APPLIED PHYSICS LETTERS, vol. 104, no. 26.
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Room temperature single photon emitters are very important resources for photonics and emerging quantum technologies. In this work, we study single photon emission from defect centers in 20 nm zinc oxide (ZnO) nanoparticles. The emitters exhibit bright broadband fluorescence in the red spectral range centered at 640 nm with polarized excitation and emission. The studied emitters showed continuous blinking; however, bleaching can be suppressed using a polymethyl methacrylate coating. Furthermore, hydrogen termination increased the density of single photon emitters. Our results will contribute to the identification of quantum systems in ZnO. © 2014 AIP Publishing LLC.
Coutts, MJ, Zareie, HM, Cortie, MB & McDonagh, AM 2014, 'Charging of gold/metal oxide/gold nanocapacitors in a scanning electron microscope', NANOTECHNOLOGY, vol. 25, no. 15.
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Cunning, BV, Ahmed, M, Mishra, N, Kermany, AR, Wood, B & Iacopi, F 2014, 'Graphitized silicon carbide microbeams: wafer-level, self-aligned graphene on silicon wafers', Nanotechnology, vol. 25, no. 32, pp. 325301-325301.
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Dowd, A, Pissuwan, D & Cortie, MB 2014, 'Optical readout of the intracellular environment using nanoparticle transducers', TRENDS IN BIOTECHNOLOGY, vol. 32, no. 11, pp. 571-577.
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Elcombe, MM, Kealley, CS, Bhatia, VK, Thorogood, GJ, Carter, DJ, Avdeev, M & Cortie, MB 2014, 'Determination of martensite structures of the Au7Cu5Al4 and Au7Cu5.7Al3.3 shape-memory alloys', ACTA MATERIALIA, vol. 79, pp. 234-240.
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The β-phase of Au 7 Cu 5 Al 4 undergoes a reversible shape-memory phase transformation for which several conflicting martensite phases have been reported. Here we show the significance of the cooling temperature used to obtain the martensite. If Au 7 Cu 5 Al 4 is cooled from the parent phase condition to cryogenic temperatures, e.g. below 200 K, the martensitic phase is orthorhombic (space group Pcmn, a = 4.4841 Å, b = 5.8996 Å, c = 17.8130 Å); however, when this composition is cooled to only ∼260 K it will in general consist of a mixture of orthorhombic and monoclinic phase (the latter has space group P2 1 /m, a = 4.4742 Å, b = 5.9265 Å, c = 13.3370 Å, β = 91.425°). In contrast, a sample with decreased Al content (Au 7 Cu 5.7 Al 3.3 ) transforms fully to monoclinic phase if cooled to ∼260 K. © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Fu, S, Luong, S, Pham, A, Charlton, N & Kuzhiumparambil, U 2014, 'Bioanalysis of urine samples after manipulation by oxidizing chemicals: technical considerations', BIOANALYSIS, vol. 6, no. 11, pp. 1543-1561.
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Gann, E, McNeill, CR, Szumilo, M, Sirringhaus, H, Sommer, M, Maniam, S, Langford, SJ & Thomsen, L 2014, 'Near-edge X-ray absorption fine-structure spectroscopy of naphthalene diimide-thiophene co-polymers', The Journal of Chemical Physics, vol. 140, no. 16, pp. 164710-164710.
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Near-edge X-ray absorption fine-structure (NEXAFS) spectroscopy is an important tool for probing the structure of conjugated polymer films used in organic electronic devices. High-performance conjugated polymers are often donor-acceptor co-polymers which feature a repeat unit with multiple functional groups. To facilitate better application of NEXAFS spectroscopy to the study of such materials, improved understanding of the observed NEXAFS spectral features is required. In order to examine how the NEXAFS spectrum of a donor-acceptor co-polymer relates to the properties of the sub-units, a series of naphthalene diimide-thiophene-based co-polymers have been studied where the nature and length of the donor co-monomer has been systematically varied. The spectra of these materials are compared with that of a thiophene homopolymer and naphthalene diimide monomer enabling peak assignment and the influence of inter-unit electronic coupling to be assessed. We find that while it is possible to attribute peaks within the π* manifold as arising primarily due to the naphthalene diimide or thiophene sub-units, very similar dichroism of these peaks is observed indicating that it may not be possible to separately probe the molecular orientation of the separate sub-units with carbon K-edge NEXAFS spectroscopy.
Guan, J, Zhang, Y, Zhou, G, Wang, C, Qu, Q, Hu, X & Wang, G 2014, 'DETERMINATION OF PROLINE, HYDROXYPROLINE, AND N–ETHYLGLYCINE IN URINE BY USING A NEW HPLC LABELING REAGENT, AND ITS APPLICATION IN DETECTION OF TUMOR MARKERS', Journal of Liquid Chromatography & Related Technologies, vol. 37, no. 12, pp. 1731-1749.
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According to previous reports, the concentration of urinary proline (Pro), hydroxyproline (Hyp), and N-ethylglycine (Neg) varies in association with various diseases, especially, Neg as a tumor marker was recently found in association with bone metastasis cancers. We developed a low-cost, highly sensitive precolumn high-performance liquid chromatography (HPLC) method for simultaneous determination of Pro, Hyp, and Neg in urine of patients with cancers, bone metastasis cancers, and bone metastasis cancers that have appeared after radiotherapy and chemotherapy treatment. The analytes in the urine were labeled with 4-methoxybenzenesulfonyl fluoride (MOBS-F) at 40°C. The derivatives were separated on a reversed-phase column by gradient elution and monitored with ultraviolet (UV) detection at 232 nm. The detection limits for Pro, Hyp, and Neg were 6.0 pmol/injection, 4.0 pmol/injection, and 50 pmol/injection (S/N = 3), respectively. To some extent, Neg levels in their urine show there were relevance to their health conditions or therapy progress. We believe that the developed method may be a promising measure for providing a useful reference to diagnose the illness and monitor the results for bone metastasis cancers after radiotherapy and chemotherapy treatment. © 2014 Copyright Taylor & Francis Group, LLC.
Guo, H, Chen, Y, Cortie, MB, Liu, X, Xie, Q, Wang, X & Peng, D-L 2014, 'Shape-Selective Formation of Monodisperse Copper Nanospheres and Nanocubes via Disproportionation Reaction Route and Their Optical Properties', JOURNAL OF PHYSICAL CHEMISTRY C, vol. 118, no. 18, pp. 9801-9808.
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Synthesis of stable and monodisperse Cu nanocrystals of controlled morphology has been a long-standing challenge. In this Article, we report a facile disproportionation reaction approach for the synthesis of such nanocrystals in organic solvents. Either spherical or cubic shapes can be produced, depending on conditions. The typical Cu nanospheres are single crystals with a size of 23.4 ± 1.5 nm, and can self-assemble into three-dimensional (3D) nanocrystal superlattices with a large scale. By manipulating the chemical additives, monodisperse Cu nanocubes with tailorable sizes have also been obtained. The probable formation mechanism of these Cu nanocrystals is discussed. The narrow size distribution results in strong surface plasmon resonance (SPR) peaks even though the resonance is located in the interband transition region. Double SPR peaks are observed in the extinction spectra for the Cu nanocubes with relative large sizes. Theoretical simulation of the extinction spectra indicates that the SPR band located at longer wavelengths is caused by assembly of Cu nanocubes into more complex structures. The synthesis procedure that we report here is expected to foster systematic investigations on the physical properties and self-assembly of Cu nanocrystals with shape and size singularity for their potential applications in photonic and nanoelectronic devices. © 2014 American Chemical Society.
Guo, X, Xiang, HF, Zhou, TP, Ju, XK & Wu, YC 2014, 'Morphologies and structures of carbon coated on Li4Ti5O12 and their effects on lithium storage performance', Electrochimica Acta, vol. 130, pp. 470-476.
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Guo, Y, Zhu, J, Lu, H, Li, Y & Jin, J 2014, 'Core Loss Computation in a Permanent Magnet Transverse Flux Motor With Rotating Fluxes', IEEE Transactions on Magnetics, vol. 50, no. 11, pp. 1-4.
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© 2014 IEEE. This paper presents the core loss computation in a permanent magnet transverse flux motor (TFM) with soft magnetic composite stator core and mild steel rotor yoke, in which the magnetic fluxes rotate. The computation is based on modified core loss models and finite element magnetic field analysis [finite element analysis (FEA)]. The coefficients for the core loss models are obtained by curve-fitting measurements on samples, and the magnetic flux density patterns in the motor are obtained by time-stepping FEA while operating conditions are considered. The computations of the motor core losses agree with the measured values on the TFM prototype.
Gupta, B, Notarianni, M, Mishra, N, Shafiei, M, Iacopi, F & Motta, N 2014, 'Evolution of epitaxial graphene layers on 3C SiC/Si (1 1 1) as a function of annealing temperature in UHV', Carbon, vol. 68, pp. 563-572.
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Hu, J, Zhu, J & Dorrell, DG 2014, 'A New Control Method of Cascaded Brushless Doubly Fed Induction Generators Using Direct Power Control', IEEE TRANSACTIONS ON ENERGY CONVERSION, vol. 29, no. 3, pp. 771-779.
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Hu, J, Zhu, J & Dorrell, DG 2014, 'In-depth study of direct power control strategies for power converters', IET POWER ELECTRONICS, vol. 7, no. 7, pp. 1810-1820.
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Hu, J, Zhu, J & Dorrell, DG 2014, 'Model predictive control of inverters for both islanded and grid-connected operations in renewable power generations', IET RENEWABLE POWER GENERATION, vol. 8, no. 3, pp. 240-248.
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Hu, J, Zhu, J & Dorrell, DG 2014, 'Model-predictive direct power control of doubly-fed induction generators under unbalanced grid voltage conditions in wind energy applications', IET RENEWABLE POWER GENERATION, vol. 8, no. 6, pp. 687-695.
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Hu, J, Zhu, J, Dorrell, DG & Guerrero, JM 2014, 'Virtual Flux Droop Method-A New Control Strategy of Inverters in Microgrids', IEEE TRANSACTIONS ON POWER ELECTRONICS, vol. 29, no. 9, pp. 4704-4711.
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Huang, X, Sun, B, Chen, S & Wang, G 2014, 'Self-Assembling Synthesis of Free-standing Nanoporous Graphene-Transition-Metal Oxide Flexible Electrodes for High-Performance Lithium-Ion Batteries and Supercapacitors', CHEMISTRY-AN ASIAN JOURNAL, vol. 9, no. 1, pp. 206-211.
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The synthesis of nanoporous graphene by a convenient carbon nanofiber assisted self-assembly approach is reported. Porous structures with large pore volumes, high surface areas, and well-controlled pore sizes were achieved by employing spherical silica as hard templates with different diameters. Through a general wet-immersion method, transition-metal oxide (Fe3O 4, Co3O4, NiO) nanocrystals can be easily loaded into nanoporous graphene papers to form three-dimensional flexible nanoarchitectures. When directly applied as electrodes in lithium-ion batteries and supercapacitors, the materials exhibited superior electrochemical performances, including an ultra-high specific capacity, an extended long cycle life, and a high rate capability. In particular, nanoporous Fe3O 4-graphene composites can deliver a reversible specific capacity of 1427.5 mAh g-1 at a high current density of 1000 mA g-1 as anode materials in lithium-ion batteries. Furthermore, nanoporous Co 3O4-graphene composites achieved a high supercapacitance of 424.2 F g-1. This work demonstrated that the as-developed freestanding nanoporous graphene papers could have significant potential for energy storage and conversion applications. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Huang, X, Sun, B, Su, D, Zhao, D & Wang, G 2014, 'Soft-template synthesis of 3D porous graphene foams with tunable architectures for lithium-O-2 batteries and oil adsorption applications', JOURNAL OF MATERIALS CHEMISTRY A, vol. 2, no. 21, pp. 7973-7979.
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We report a general emulsion soft-template method to synthesize porous graphene foams for multi-functional applications, including lithium-oxygen batteries and oil-adsorption. Multiple micro-emulsions and micelles were employed to produce three-dimensional porous graphene with well-tailored inter-architecture for the first time. Detailed mechanism study reveals that specific interfacial interactions, such as π-π interaction, hydrophobic affinity or electrostatic interaction, are vital for the formation of porous graphene materials. When applied as cathode materials in lithium-oxygen batteries, the porous graphene foams exhibited good catalytic activity. Besides, the porous graphene materials also demonstrated the capability for oil adsorption with a high efficiency. This journal is © the Partner Organisations 2014.
Huangfu, Y, Wang, S, Qiu, J, Zhang, H, Wang, G & Zhu, J 2014, 'Transient Performance Analysis of Induction Motor Using Field-Circuit Coupled Finite-Element Method', IEEE Transactions on Magnetics, vol. 50, no. 2, pp. 873-876.
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In this paper, the application of field-circuit coupled finite-element method for predicting the performance of induction motor (IM) under a sinusoidal voltage excitation is described. The numerical analysis is performed by solving the nonlinear time-stepping finite-element equations coupled with the circuit equations and mechanical motion equations. The circuit equations are described by means of improved nodal method. The local analytical solution of Laplace equation is used to improve the precision of electromagnetic torque. The performances of both three-and single-phase IMs are simulated using the developed field-circuit coupled code. The comparison among the results calculated by the code, the commercial FE package, FLUX 2-D, and the experiment results suggests the correctness of the field-circuit coupled method and related developed code.
Islam, MR, Guo, Y & Zhu, J 2014, 'A High-Frequency Link Multilevel Cascaded Medium-Voltage Converter for Direct Grid Integration of Renewable Energy Systems', IEEE Transactions on Power Electronics, vol. 29, no. 8, pp. 4167-4182.
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Recent advances in solid-state semiconductors have led to the development of medium-voltage power converters (e.g., 6-36 kV) which could obviate the need for the step-up transformers of renewable power generation systems. The modular multilevel cascaded converters have been deemed as strong contenders for the development of medium-voltage converters, but the converters require multiple isolated and balanced dc supplies. In this paper, a high-frequency link multilevel cascaded medium-voltage converter is proposed. The common high-frequency link generates multiple isolated and balanced dc supplies for the converter, which inherently minimizes the voltage imbalance and common mode issues. An 11-kV system is designed and analyzed taking into account the specified system performance, control complexity, cost, and market availability of the power semiconductors. To verify the feasibility of the proposed system, a scaled down 1.73-kVA laboratory prototype test platform with a modular five-level cascaded converter is developed and explored in this paper, which converts a 210 V dc (rectified generator voltage) into three-phase 1 kV rms 50 Hz ac. The experimental results are analyzed and discussed. It is expected that the proposed new technology will have great potential for future renewable generation systems and smart grid applications. © 2013 IEEE.
Islam, MR, Guo, Y & Zhu, J 2014, 'A Multilevel Medium-Voltage Inverter for Step-Up-Transformer-Less Grid Connection of Photovoltaic Power Plants', IEEE Journal of Photovoltaics, vol. 4, no. 3, pp. 881-889.
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Recently, medium (0.1-5 MW) and large (>5 MW) scale photovoltaic (PV) power plants have attracted great attention, where medium-voltage grid connection (typically 6-36 kV) is essential for efficient power transmission and distribution. A power frequency transformer operated at 50 or 60 Hz is generally used to step up the traditional inverter's low output voltage (usually =400 V) to the medium-voltage level. Because of the heavy weight and large size of the power frequency transformer, the PV inverter system can be expensive and complex for installation and maintenance. As an alternative approach to achieve a compact and lightweight direct grid connection, this paper proposes a three-phase medium-voltage PV inverter system. The 11-kV and 33-kV PV inverter systems are designed. A scaled down three-phase 1.2-kV test rig has been constructed to validate the proposed PV inverter. The experimental results are analyzed and discussed, taking into account the switching schemes and filter circuits. The experimental results demonstrate the excellent feature of the proposed PV inverter system.
Islam, MR, Guo, Y & Zhu, J 2014, 'A review of offshore wind turbine nacelle: Technical challenges, and research and developmental trends', Renewable and Sustainable Energy Reviews, vol. 33, pp. 161-176.
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The turbine nacelle with traditional wind power generation system is heavy, especially in offshore applications due to the large mass of the power frequency step-up-transformer operated at 50 or 60 Hz, and copper conductor generator. For example, the weight and volume of a 0.69/33 kV 2.6 MVA transformer are typically in the range of 68 t and 59 m3, respectively. The weight for a 10 MW direct drive permanent magnet generator is about 300 t. These penalties significantly increase the tower construction, and turbine installation and maintenance costs. The tower cost represents 26% of the total component cost of the turbine and on average about 20% of the capital costs are associated with installation. Typical maintenance cost of an offshore wind turbine is about 2.3 cents/kW.h, which is 20% higher than that of an onshore based turbine. As alternative approaches to achieve a compact and lightweight offshore wind turbine nacelle, different concepts have been proposed in recent years, such as step-up-transformer-less system, medium-frequency (in the range of a few kHz to MHz) power transformer-based system, multilevel and modular matrix converter-based system and superconducting generator-based system. This paper aims to review the technical challenges, current research and developmental trends, and possible future directions of the research to reduce the weight and volume of the nacelle. In addition, a comprehensive review of traditional wind power generation technologies is conducted in this article as well.
Islam, MR, Lei, G, Guo, Y & Zhu, J 2014, 'Optimal Design of High-Frequency Magnetic Links for Power Converters Used in Grid-Connected Renewable Energy Systems', IEEE Transactions on Magnetics, vol. 50, no. 11, pp. 1-4.
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Islam, MR, Youguang Guo, Jianguo Zhu, Haiyan Lu & Jian Xun Jin 2014, 'High-Frequency Magnetic-Link Medium-Voltage Converter for Superconducting Generator-Based High-Power Density Wind Generation Systems', IEEE Transactions on Applied Superconductivity, vol. 24, no. 5, pp. 1-5.
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Kajer, TB, Fairfull-Smith, KE, Yamasaki, T, Yamada, K-I, Fu, S, Bottle, SE, Hawkins, CL & Davies, MJ 2014, 'Inhibition of myeloperoxidase- and neutrophil-mediated oxidant production by tetraethyl and tetramethyl nitroxides', FREE RADICAL BIOLOGY AND MEDICINE, vol. 70, pp. 96-105.
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The powerful oxidant HOCl (hypochlorous acid and its corresponding anion, OCl) generated by the myeloperoxidase (MPO)H2O2Cl system of activated leukocytes is strongly associated with multiple human inflammatory diseases; consequently there is considerable interest in inhibition of this enzyme. Nitroxides are established antioxidants of low toxicity that can attenuate oxidation in animal models, with this ascribed to superoxide dismutase or radical-scavenging activities. We have shown (M.D. Rees et al., Biochem. J. 421, 7986, 2009) that nitroxides, including 4-amino-TEMPO (4-amino-2,2,6,6-tetramethylpiperidin-1-yloxyl radical), are potent inhibitors of HOCl formation by isolated MPO and activated neutrophils, with IC50 values of 1 and 6 mM respectively. The utility of tetramethyl-substituted nitroxides is, however, limited by their rapid reduction by biological reductants. The corresponding tetraethyl-substituted nitroxides have, however, been reported to be less susceptible to reduction. In this study we show that the tetraethyl species were reduced less rapidly than the tetramethyl species by both human plasma (8999% decreased rate of reduction) and activated human neutrophils (6275% decreased rate). The tetraethyl-substituted nitroxides retained their ability to inhibit HOCl production by MPO and activated neutrophils with IC50 values in the low-micromolar range; in some cases inhibition was enhanced compared to tetramethyl substitution. Nitroxides with rigid structures (fused oxaspiro rings) were, however, inactive. Overall, these data indicate that tetraethyl-substituted nitroxides are potent inhibitors of oxidant formation by MPO, with longer plasma and cellular half-lives compared to the tetramethyl species, potentially allowing lower doses to be employed.
Keast, VJ, Barnett, RL & Cortie, MB 2014, 'First principles calculations of the optical and plasmonic response of Au alloys and intermetallic compounds', JOURNAL OF PHYSICS-CONDENSED MATTER, vol. 26, no. 30.
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Kermany, AR, Brawley, G, Mishra, N, Sheridan, E, Bowen, WP & Iacopi, F 2014, 'Microresonators with Q-factors over a million from highly stressed epitaxial silicon carbide on silicon', Applied Physics Letters, vol. 104, no. 8, pp. 081901-081901.
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We utilize the excellent mechanical properties of epitaxial silicon carbide (SiC) on silicon plus the capability of tuning its residual stress within a large tensile range to fabricate microstrings with fundamental resonant frequencies (f0) of several hundred kHz and mechanical quality factors (Q) of over a million. The fabrication of the perfect-clamped string structures proceeds through simple silicon surface micromachining processes. The resulting f × Q product in vacuum is equal or higher as compared to state-of-the-art amorphous silicon nitride microresonators. We demonstrate that as the residual epitaxial SiC stress is doubled, the f × Q product for the fundamental mode of the strings shows a four-fold increase.
Khalil, A, Ishita, K, Ali, T, Tiwari, R, Riachy, R, Toppino, A, Hasabelnaby, S, Sayfullin, N, Oliver, AG, Gallucci, J, Huang, Z & Tjarks, W 2014, 'Iodine Monochloride Facilitated Deglycosylation, Anomerization, and Isomerization of 3-Substituted Thymidine Analogues', Nucleosides, Nucleotides & Nucleic Acids, vol. 33, no. 12, pp. 786-799.
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Lei, G, Wang, T, Guo, Y, Zhu, J & Wang, S 2014, 'System-Level Design Optimization Methods for Electrical Drive Systems: Deterministic Approach', IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, vol. 61, no. 12, pp. 6591-6602.
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© 1982-2012 IEEE. Electrical drive systems are key components in modern appliances, industry equipment, and systems, e.g., hybrid electric vehicles. To obtain the best performance of these drive systems, the motors and their control systems should be designed and optimized at the system level rather than the component level. This paper presents an effort to develop system-level design and optimization methods for electrical drive systems. Two system-level design optimization methods are presented in this paper: 1) single-level method (only at system level); and 2) multilevel method. Meanwhile, the approximate models, the design of experiments technique, and the sequential subspace optimization method are presented to improve the optimization efficiency. Finally, a drive system consisting of a permanent-magnet transverse flux machine with a soft magnetic composite core is investigated, and detailed results are presented and discussed. This is a high-dimensional optimization problem with 14 parameters mixed with both discrete and continuous variables. The finite-element analysis model and method are verified by the experimental results on the motor prototype. From the discussion, it can be found that the proposed multilevel method can increase the performance of the whole drive system, such as bigger output power and lower material cost, and decrease the computation cost significantly compared with those of single-level design optimization method.
Lei, G, Xu, W, Hu, J, Zhu, J, Guo, Y & Shao, K 2014, 'Multilevel Design Optimization of a FSPMM Drive System by Using Sequential Subspace Optimization Method', IEEE TRANSACTIONS ON MAGNETICS, vol. 50, no. 2.
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Lei, G, Zhu, J, Guo, Y, Shao, K & Xu, W 2014, 'Multiobjective Sequential Design Optimization of PM-SMC Motors for Six Sigma Quality Manufacturing', IEEE TRANSACTIONS ON MAGNETICS, vol. 50, no. 2, pp. 1-4.
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In our previous work, two kinds of permanent magnet (PM) synchronous motors, transverse flux motor (TFM) and claw pole motor, were designed and fabricated using the soft magnetic composite (SMC) cores. This paper presents multiobjective and robust design optimization for high-quality manufacturing of these PM-SMC motors to improve their industrial applications. Meanwhile, an improved multiobjective sequential optimization method is presented to reduce the computation cost. Thereafter, a PM TFM with SMC core is investigated to illustrate the performance of the proposed method. From the discussion, it can be found that six sigma quality manufacturing was achieved for all Pareto design schemes given by the proposed method. Furthermore, manufacturing cost and computation cost have been reduced a lot. © 2014 IEEE.
Lem, LLC, Phillips, MR & Ton-That, C 2014, 'Controlling the visible luminescence in hydrothermal ZnO', JOURNAL OF LUMINESCENCE, vol. 154, pp. 387-391.
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Cathodoluminescence spectra have been measured in hydrothermal and hydrogen-doped ZnO at different excitation densities and temperatures to investigate the emission efficiencies of near-band-edge (NBE), green and yellow luminescence bands. The NBE intensity depends linearly on the electron beam excitation as expected for excitonic recombination character. The intensities of the green and yellow bands are highly dependent not only on the excitation density but also on temperature. At high excitation densities ZnO exhibits dominant green emission at room temperature; the intensity of the green band can be further controlled by doping ZnO with hydrogen, which passivates green luminescence centers. Conversely at small excitation densities (< 0.1 nA) and low temperatures the visible luminescence from ZnO is predominantly yellow due to the abundance of Li in hydrothermal ZnO. The results are explained by differences in the recombination kinetics and the relative concentrations of the green and yellow centers, and illustrate that single-color emission can be achieved in ZnO by adjusting the excitation power and temperature. © 2014 Published by Elsevier B.V. All rights reserved.
Li, D, Liu, F, Li, Y, Zhao, Z, Zhang, C & Yang, Q 2014, 'Magnetic properties modeling of soft magnetic composite materials using two-dimensional vector hybrid hysteresis model', Journal of Applied Physics, vol. 115, no. 17, pp. 17D117-17D117.
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Thanks to the unique magnetic properties, soft magnetic composite (SMC) materials and their application in electromagnetic devices have achieved significant development. The typical application example of SMC is the electrical machine with complex structure, such as claw pole and transverse flux machines, in which the magnetic field is basically rotary. To design and analyze such a device, vector magnetic properties of the core material should be properly determined, modeled and applied. This paper presents the modeling of vector magnetic hysteresis of SMC based on a Stoner-Wohlfarh (S-W) elemental operator. A phenomenological mean-field approximation is used to consider the interaction between particles. With the presented model, the magnetization processes of SMC under both alternating and rotating fluxes are numerically simulated. The simulations have been verified by experimental measurements.
Li, K, Liu, H & Wang, G 2014, 'Sb2O3 Nanowires as Anode Material for Sodium-Ion Battery', ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING, vol. 39, no. 9, pp. 6589-6593.
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The anodic properties of antimony trioxide (Sb2O3) nanowires were investigated as electrode material for sodium-ion battery. Sb2O3 nanowires were prepared via a mild-condition, solvothermal route based on the hydrolysis of antimony trichloride (SbCl3) in alcohol aqueous solution. The uniform morphology and crystal phases of Sb2O3 nanowires are confirmed by scanning electronic microscopy, transmission electronic microscopy, and X-ray diffraction. The electrochemical performance of Sb2O3 nanowire anodes was studied and thematerial exhibits a high reversible capacity of 230 mAh/g which is attributed to the reversible complex conversion-alloying reactions between antimony trioxide and sodium.
Li, Y, Yang, Q, Zhu, J, Zhao, Z, Liu, X & Zhang, C 2014, 'Design and Analysis of a Novel 3-D Magnetization Structure for Laminated Silicon Steel', IEEE Transactions on Magnetics, vol. 50, no. 2, pp. 389-392.
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A novel 3-D magnetic properties tester for laminated silicon steel specimen has been designed and constructed. The magnetization structure is the critical part of the tester especially for the magnetic properties of the laminated silicon steel in perpendicular direction of grain oriented. To guarantee the experimental precision and accurately analyze the 3-D magnetic properties of the laminated silicon steel, a symmetrical 3-D magnetic flux path in the magnetization structure fit for given dimension of specimen has been calculated and modeled. Magnetic flux in each direction has been homogenized and concentrated on the top of the core poles through finite element analysis. Therefore, magnetic properties in each direction of the laminated specimen can be really concerned and analyzed in practical engineering.
Liu, H & Wang, G 2014, 'An investigation of the morphology effect in Fe2O3 anodes for lithium ion batteries', JOURNAL OF MATERIALS CHEMISTRY A, vol. 2, no. 26, pp. 9955-9959.
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Morphology control strategies have been widely used to boost the tolerance of anode materials against a dramatic volume change during charge/discharge processes. Herein, we found solid scientific evidence demonstrating that the electrochemical properties of cavity containing materials are superior to their solid counterparts.
Liu, J, Liu, H, Yang, T, Wang, G & Tade, MO 2014, 'Mesoporous carbon with large pores as anode for Na-ion batteries', CHINESE SCIENCE BULLETIN, vol. 59, no. 18, pp. 2186-2190.
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Sodium ion (Na+) batteries have attracted increased attention for energy storage owing to the natural abundance and low cost of sodium. Herein, we report the synthesis of mesoporous carbon with large pores as anode for Na-ion batteries. The mesoporous carbon was obtained by carbonization and dense packing of 50 nm resorcinol and formaldehyde spheres synthesized through an extension Stöber method. Our work demonstrates that replacement of lithium by sodium using large pore carbon as anode might offer an alternative route for rechargeable batteries.
Liu, Q, Yang, Y, Sun, B, Su, D, Li, Z, Xia, Q & Wang, G 2014, 'Hydrothermal synthesis of FeP4 and Fe2P-loaded alpha-Fe2O3 hollow spheres and applications in gas sensors', SENSORS AND ACTUATORS B-CHEMICAL, vol. 194, pp. 27-32.
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FeP4 and Fe2P-loaded hematite (α-Fe 2O3) (FFH) hollow spheres with a diameter of 130-410 nm were synthesized by a hydrothermal method. The structure and morphology of the FFH hollow spheres were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), field-emission scanning electron microscope (FESEM), and X-ray photoelectron spectroscopy (XPS). Nitrogen adsorption-desorption isothermal measurements revealed that the FFH hollow spheres have larger BET surface area and mesopores. The gas-sensing performance of the FFH hollow spheres was investigated towards a series of typical organic solvents and fuels. The FFH hollow spheres exhibited a superior sensitivity towards flammable and irritant gases. The possible sensing mechanism of the FFH hollow spheres sensor is also proposed. © 2013 Elsevier B.V.
Lu, A, Chen, Y, Li, H, Dowd, A, Cortie, MB, Xie, Q, Guo, H, Qi, Q & Peng, D-L 2014, 'Magnetic metal phosphide nanorods as effective hydrogen-evolution electrocatalysts', INTERNATIONAL JOURNAL OF HYDROGEN ENERGY, vol. 39, no. 33, pp. 18919-18928.
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Luong, S & Fu, S 2014, 'Detection and identification of 2-nitro-morphine and 2-nitro- morphine-6-glucuronide in nitrite adulterated urine specimens containing morphine and its glucuronides', DRUG TESTING AND ANALYSIS, vol. 6, no. 3, pp. 277-287.
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In vitro urine adulteration is a well-documented practice adopted by individuals aiming to evade detection of drug use, when required to undergo mandatory sports and workplace drug testing. Potassium nitrite is an effective urine adulterant due to its oxidizing potential, and has been shown to mask the presence of many drugs of abuse. However, limited research has been conducted to understand its mechanism of action, and to explore the possibility of the drugs undergoing direct oxidation to form stable reaction products. In this study, opiates including morphine, codeine, morphine-3-glucuronide and morphine-6-glucuronide were exposed to potassium nitrite in water and urine to mimic the process of nitrite adulteration. It was found that two stable reaction products were detected by liquid chromatography-mass spectrometry (LC-MS) when morphine and morphine-6-glucuronide were exposed to nitrite. Isolation and elucidation using spectrometric and spectroscopic techniques revealed that they were 2-nitro-morphine and 2-nitro-morphine-6-glucuronide, respectively. These reaction products were also formed when an authentic morphine-positive urine specimen was fortified with nitrite. 2-Nitro-morphine was found to be stable enough to undergo the enzymatic hydrolysis procedure and also detectable by gas chromatography-mass spectrometry (GC-MS) after forming a trimethylsilyl derivative. On the contrary, morphine-3-glucuronide did not appear to be chemically manipulated when exposed to potassium nitrite in urine.
Luong, S, Ung, AT, Kalman, J & Fu, S 2014, 'Transformation of codeine and codeine-6-glucuronide to opioid analogues by urine adulteration with pyridinium chlorochromate: potential issue for urine drug testing', RAPID COMMUNICATIONS IN MASS SPECTROMETRY, vol. 28, no. 14, pp. 1609-1620.
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Mahamedi, B & Zhu, JG 2014, 'Unsynchronized Fault Location Based on the Negative-Sequence Voltage Magnitude for Double-Circuit Transmission Lines', IEEE Transactions on Power Delivery, vol. 29, no. 4, pp. 1901-1908.
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Makume, BF, Bredenkamp, T & Williams, DBG 2014, 'Substrate Requirements for Palladium–Aluminium Triflate Co‐catalysed Hydromethoxycarbonylation Reactions of Alkynes Bearing Oxygen Atoms', ChemCatChem, vol. 6, no. 10, pp. 2801-2804.
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AbstractThe palladium diacetate–aluminium triflate combination is an effective catalyst for the hydromethoxycarbonylation reaction of isolated alkenes and alkynes. However, its application in the hydromethoxycarbonylation of oxygen atom‐bearing alkynes is non‐trivial: the position relative to the alkyne (e.g., allylic, homoallylic) and nature of the oxygen atom determine the success of the transformation. We detail the minimum structural requirements for a successful outcome with ether‐containing alkyne substrates and hydroxyl‐containing analogues. In general, the oxygen atom has a detrimental effect on the outcome of the hydromethoxycarbonylation reaction, which can be overcome in many instances. The presence of the oxygen atom(s) causes decreases in the rate of the reaction compared to aliphatic alkynes and the closer the oxygen atom is to the triple bond, the more pronounced the effect. The chemistry is demonstrated on complex substrates derived from 5 and 6‐carbon sugars in optimised reactions.
Maniam, S, Higginbotham, HF, Guo, S, Bell, TDM, Izgorodina, EI & Langford, SJ 2014, 'A Redox Switchable Dihydrobenzo[b]pyrazine Push‐Pull System', Asian Journal of Organic Chemistry, vol. 3, no. 5, pp. 619-623.
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AbstractThe synthesis and spectroscopic properties of a dissymmetrically core‐extended naphthalene diimides derived from o‐phenylenediamine and cyanoethene dithiolate were explored. The push‐pull nature of the peripheral substituents allows these naphthalene diimide dyes and their progenitors to display interesting photophysical and electrochemical properties, with the target system acting as a highly reversible and quantitative molecular switch with clear absorption and emission readouts based on chemical oxidation and reduction processes.
McPherson, DJ, Supansomboon, S, Zwan, B, Keast, VJ, Cortie, DL, Gentle, A, Dowd, A & Cortie, MB 2014, 'Strategies to control the spectral properties of Au-Ni thin films', THIN SOLID FILMS, vol. 551, pp. 200-204.
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Middleburgh, SC, King, DM, Lumpkin, GR, Cortie, M & Edwards, L 2014, 'Segregation and migration of species in the CrCoFeNi high entropy alloy', JOURNAL OF ALLOYS AND COMPOUNDS, vol. 599, pp. 179-182.
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The formation and migration of intrinsic defects in the CrCoFeNi high entropy alloy has been investigated using ab-initio modeling. The ease of vacancy formation was found to vary depending on the element: vacancies formed by the removal of Fe, Ni and Co are positive while Cr has a negative vacancy formation energy and will precipitate out of the CrCoFeNi alloy. This mechanism may allow the formation of a corrosion passivating oxide layer, analogous to Cr behaviour in stainless steels. The migration and behaviour of intrinsic interstitial defects has also been investigated. © 2014 Published by Elsevier B.V. All rights reserved.
Mishra, N, Hold, L, Iacopi, A, Gupta, B, Motta, N & Iacopi, F 2014, 'Controlling the surface roughness of epitaxial SiC on silicon', Journal of Applied Physics, vol. 115, no. 20, pp. 203501-203501.
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The surface of cubic silicon carbide (3C-SiC) hetero-epitaxial films grown on the (111) surface of silicon is a promising template for the subsequent epitaxial growth of III-V semiconductor layers and graphene. We investigate growth and post-growth approaches for controlling the surface roughness of epitaxial SiC to produce an optimal template. We first explore 3C-SiC growth on various degrees of offcut Si(111) substrates, although we observe that the SiC roughness tends to worsen as the degree of offcut increases. Hence we focus on post-growth approaches available on full wafers, comparing chemical mechanical polishing (CMP) and a novel plasma smoothening process. The CMP leads to a dramatic improvement, bringing the SiC surface roughness down to sub-nanometer level, though removing about 200 nm of the SiC layer. On the other hand, our proposed HCl plasma process appears very effective in smoothening selectively the sharpest surface topography, leading up to 30% improvement in SiC roughness with only about 50 nm thickness loss. We propose a simple physical model explaining the action of the plasma smoothening.
Moezzi, A, Cortie, M, Dowd, A & McDonagh, A 2014, 'On the formation of nanocrystalline active zinc oxide from zinc hydroxide carbonate', JOURNAL OF NANOPARTICLE RESEARCH, vol. 16, no. 4.
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Molnar, A, Fu, S, Lewis, J, Allsop, DJ & Copeland, J 2014, 'The detection of THC, CBD and CBN in the oral fluid of Sativex (R) patients using two on-site screening tests and LC-MS/MS', FORENSIC SCIENCE INTERNATIONAL, vol. 238, pp. 113-119.
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Sativex® is an oromucosal spray used to treat spasticity in multiple sclerosis sufferers in some European countries, the United Kingdom, Canada and New Zealand. The drug has also recently been registered by the Therapeutic Goods Administration (TGA) in Australia for treatment of multiple sclerosis. Sativex® contains high concentrations of ?9-tetrahydrocannabinol (THC) and cannabidiol (CBD), with the former being the subject of random roadside drug tests across Australia to detect cannabis use. This pilot study aims to determine whether or not patients taking Sativex® will test positive to THC using these roadside screening tests. Detectable levels of THC, CBD and cannabinol (CBN) in their oral fluid were also confirmed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The study was a double-blind, placebo controlled design. Oral fluid was tested prior to and immediately after dosing with either Sativex® or placebo at intervals up to 2 h after the dose. Two Sativex® doses were studied. The low dose contained 5.4 mg THC, the high dose 21.6 mg THC. Results indicate that the primary screening test used in Australian roadside drug testing, the DrugWipe® II Twin, often gave a false negative response for THC, even with high concentrations present. However, secondary screening test, Cozart® DDS (used by police after a DrugWipe test gives a positive result), gave true positive results in all cases where patients were being treated with Sativex1. Confirmatory testing showed high concentrations of THC and CBD (>5356 ng/mL THC and >3826 ng/mL CBD) in the oral fluid shortly after dosing and also elevated concentrations of CBN. Levels dropped quickly but remained at detectable concentrations (>67.6 ng/mL) two hours after drug administration. The average concentration ratio of THC/CBD across all positive samples was 1.10 (%RSD 19.9) reflecting the composition of the Sativex® spray. In conclusion, Sativex® users may test positive for THC by roadside drug testing wi...
Mondal, AK, Chen, S, Su, D, Liu, H & Wang, G 2014, 'Fabrication and enhanced electrochemical performances of MoO3/graphene composite as anode material for lithium-ion batteries', International Journal of Smart Grid and Clean Energy, vol. 3, no. 2, pp. 142-148.
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Molybdenum trioxide (Mo0#)/graphene composite were prepared by integrating Mo03 and graphene in dimethylformamide (DMF). The morphology and structure of the materials were characterized by X-ray diffraction, field emission scanning electron microscopy and transmission electron microscopy. The electrochemical properties of Mo03/graphene composite with different ratios were studied as anode materials for lithium-ion batteries using galavanostatic charge-discharge and cyclic voltammetry. We observed that the Mo03/graphene anode with a weight ratio of 1:1 (Mo03 graphene) exhibits a high lithium storage capacity of 967 mA h g-1 at the current density of 500 mA g-1, satisfactory cycling stability and good rate capability.
Mondal, AK, Su, D, Chen, S, Sun, B, Li, K & Wang, G 2014, 'A simple approach to prepare nickel hydroxide nanosheets for enhanced pseudocapacitive performance', RSC ADVANCES, vol. 4, no. 37, pp. 19476-19481.
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Nickel hydroxide nanosheets were synthesized by a simple microwave assisted heating method and investigated as electrochemical pseudo-capacitive materials for supercapacitors. The crystalline structure and morphology of the as-obtained Ni(OH)2 nanosheets were characterized by X-ray diffraction, nitrogen adsorption-desorption isotherms, field emission scanning electron microscopy and transmission electron microscopy. The electrochemical properties of the Ni(OH)2 nanosheets were evaluated by cyclic voltammetry and chronopotentiometry technology in 2 M KOH solution. The nickel hydroxide nanosheet electrode shows a maximum specific capacitance of 2570 F g -1 at a current density of 5 A g-1 and exhibits superior cycling stability. These results suggest its potential application as an electrode material for supercapacitors. © the Partner Organisations 2014.
Mondal, AK, Su, D, Chen, S, Xie, X & Wang, G 2014, 'Highly Porous NiCo2O4 Nanoflakes and Nanobelts as Anode Materials for Lithium-Ion Batteries with Excellent Rate Capability', ACS Applied Materials & Interfaces, vol. 6, no. 17, pp. 14827-14835.
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Mondal, AK, Su, D, Chen, S, Zhang, J, Ung, A & Wang, G 2014, 'Microwave-assisted synthesis of spherical β-Ni(OH) 2 superstructures for electrochemical capacitors with excellent cycling stability', Chemical Physics Letters, vol. 610-611, pp. 115-120.
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A novel single-step microwave-assisted process has been developed to synthesize spherical β-Ni(OH)2 superstructures without using any templates. Structure characterizations show that the spherical β-Ni(OH)2 composed of twisted nanosheets was obtained. The electrochemical properties of the as-prepared materials were evaluated by cyclic voltammetry and chronopotentiometry technology in 2 M KOH solution. Due to the unique morphology, the prepared β-Ni(OH)2 electrode displays a high specific capacitance of 2147 F g-1 at a discharge current of 1 A g-1 and outstanding cycling stability (99.5% capacitance retained after 2000 cycles), suggesting its potential application as an efficient electrode material for high-performance electrochemical capacitors. © 2014 Elsevier B.V.
Mondal, AK, Su, D, Wang, Y, Chen, S, Liu, Q & Wang, G 2014, 'Microwave hydrothermal synthesis of urchin-like NiO nanospheres as electrode materials for lithium-ion batteries and supercapacitors with enhanced electrochemical performances', JOURNAL OF ALLOYS AND COMPOUNDS, vol. 582, no. 1, pp. 522-527.
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Urchin-like NiO nanospheres were synthesised by a microwave hydrothermal method. The as-synthesised NiO nanospheres were characterised by X-ray diffraction, field emission scanning electron microscopy and transmission electron microscopy. It was found that NiO nanosphere consists of a nanoporous structure and nanosize crystals. When applied as anode materials in lithium-ion batteries, NiO nanospheres exhibited a high reversible specific capacity of 1027 mA h g-1, an excellent cycling performance and a good high rate capability. NiO nanospheres also showed a high specific capacitance as electrode materials for supercapacitors. © 2013 Elsevier B.V. All rights reserved.
Mondal, AK, Wang, B, Su, D, Wang, Y, Chen, S, Zhang, X & Wang, G 2014, 'Graphene/MnO2 hybrid nanosheets as high performance electrode materials for supercapacitors', Materials Chemistry and Physics, vol. 143, no. 2, pp. 740-746.
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Graphene/MnO2 hybrid nanosheets were prepared by incorporating graphene and MnO2 nanosheets in ethylene glycol. Scanning electron microscopy and transmission electron microscopy analyses confirmed nanosheet morphology of the hybrid materials. Graphene/MnO2 hybrid nanosheets with different ratios were investigated as electrode materials for supercapacitors by cyclic voltammetry (CV) and galvanostatic charge-discharge in 1 M Na2SO4 electrolyte. We found that the graphene/MnO2 hybrid nanosheets with a weight ratio of 1:4 (graphene:MnO2) delivered the highest specific capacitance of 320 F g-1. Graphene/MnO2 hybrid nanosheets also exhibited good capacitance retention on 2000 cycles. © 2013 Elsevier B.V. All rights reserved.
Porter, SH, Huang, Z & Woodward, PM 2014, 'Study of Anion Order/Disorder in RTaN2O (R = La, Ce, Pr) Perovskite Nitride Oxides', Crystal Growth & Design, vol. 14, no. 1, pp. 117-125.
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Rabiul Islam, M, Guo, Y, Wei Lin, Z & Zhu, J 2014, 'An amorphous alloy core medium frequency magnetic-link for medium voltage photovoltaic inverters', Journal of Applied Physics, vol. 115, no. 17, pp. 17E710-17E710.
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The advanced magnetic materials with high saturation flux density and low specific core loss have led to the development of an efficient, compact, and lightweight multiple-input multiple-output medium frequency magnetic-link. It offers a new route to eliminate some critical limitations of recently proposed medium voltage photovoltaic inverters. In this paper, a medium frequency magnetic-link is developed with Metglas amorphous alloy 2605S3A. The common magnetic-link generates isolated and balanced multiple DC supplies for all of the H-bridge inverter cells of the medium voltage inverter. The design and implementation of the prototype, test platform, and the experimental test results are analyzed and discussed. The medium frequency non-sinusoidal excitation electromagnetic characteristics of alloy 2605S3A are also compared with that of alloy 2605SA1. It is expected that the proposed new technology will have great potential for future renewable power generation systems and smart grid applications.
Sandanayake, S & Langford, SJ 2014, 'Crown Ether Derivatised Pyromellitic Diimides', Australian Journal of Chemistry, vol. 67, no. 9, pp. 1264-1264.
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Pyromellitic diimide functionalised on the aromatic core with azacrown ethers have been synthesised and characterised by analytical methods including X-ray crystallography. Changes in their UV-vis spectra by the addition of metal salts have been investigated.
Simelane, SB, Kinfe, HH, Muller, A & Williams, DBG 2014, 'Aluminum Triflate Catalyzed Tandem Reactions of d-Galactal: Toward Chiral Benzopyrans, Chromenes, and Chromans', Organic Letters, vol. 16, no. 17, pp. 4543-4545.
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© 2014 American Chemical Society. 3,4,6-Tri-O-acetyl-d-galactal is selectively converted into 1-O-aryl-2-deoxy derivatives or chiral bridged benzopyrans under Al(OTf)3 catalysis, depending on reaction conditions. The benzopyrans react with Al(OTf)3/acetic anhydride in ring-opening reactions in the absence or presence of acetic acid to selectively produce chiral chromenes or chromans, respectively, in high yields.
Stojanovska, N, Kelly, T, Tahtouh, M, Beavis, A & Fu, S 2014, 'Analysis of amphetamine-type substances and piperazine analogues using desorption electrospray ionisation mass spectrometry', RAPID COMMUNICATIONS IN MASS SPECTROMETRY, vol. 28, no. 7, pp. 731-740.
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RATIONALE: Although amphetamine-type substances (ATS) have been investigated extensively in recent years, scarce data is available on screening tests for piperazine analogues. The need for a universal technique capable of detecting an extensive range of drug compounds becomes increasingly important with the continued emergence of novel drug analogues. METHODS: Desorption electrospray ionisation mass spectrometry (DESI-MS) is a technique that allows examination of compounds in drug materials directly from ambient surfaces. In this study, DESI-MS was utilised in the analysis of ATS including amphetamine (AP), methylamphetamine (MA), 3,4-methylenedioxymethylamphetamine (MDMA), N,N-dimethylamphetamine (DMA), 4-methoxyamphetamine (PMA) and 4-methoxymethylamphetamine (PMMA), and piperazine analogues including 1-benzylpiperazine (BZP), 1-[3-trifluoromethyl)phenyl]piperazine (TFMPP), 1-(3- chlorophenyl)piperazine (mCPP) and 1-(4-methoxyphenyl)piperazine (MeOPP). Semi-porous polytetrafluoroethylene (PTFE or Teflon) sheets welled with a 3 mm hole punch were used to contain the 2 µL liquid sample (spot size 7 mm2). RESULTS: The limits of detection (LODs) of these compounds using DESI-MS were determined to be in the range 0.022.80 µg/mm2. The intra-day and inter-day precision of the technique were <25% and <33%, respectively. DESI-MS was successful in determining the compound of interest and reaction by-products and impurities in the samples tested (such as 1,4-dibenzylpiperazine in BZP samples) with the exception of those present in trace amounts. The effects of common adulterants on the detectability of MA were evaluated. The addition of magnesium stearate to MA significantly enhanced the signal response. CONCLUSIONS: This work has demonstrated the applicability of DESI-MS in the screening and profiling of MDMA, PMMA, BZP, TFMPP, mCPP, MeOPP as well as other complex mixtures. Copyright © 2014 John Wiley & Sons, Ltd.
Stojanovska, N, Tahtouh, M, Kelly, T, Beavis, A & Fu, S 2014, 'Presumptive analysis of 4-methylmethcathinone (mephedrone) using Desorption Electrospray Ionisation - Mass Spectrometry (DESI-MS)', AUSTRALIAN JOURNAL OF FORENSIC SCIENCES, vol. 46, no. 4, pp. 411-423.
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4-Methylmethcathione (4-MMC or mephedrone) is a prevalent drug of abuse globally. 4-MMC is often marketed as `bath salts and is readily available over the internet. The need for a rapid universal technique capable of detecting an extensive range of drug compounds has become increasingly important with the continued emergence of novel drug analogues. Desorption electrospray ionisation - mass spectrometry (DESI-MS) is a mass spectrometry technique that allows for the analysis of compounds directly from ambient surfaces, reducing or eliminating the need for sample preparation. Although 4-MMC has gained significant attention in recent years, the application of the DESI-MS technique to the fast presumptive detection and chemical analysis of this analogue has not been presented. In the present study, DESI-MS was applied to the rapid qualitative analysis of 4-MMC. A particularly suitable surface, semi-porous polytetrafluoroethylene (PTFE, Teflon) was utilised, as it generated the least variable signal and reproducibility compared to other surfaces (polymethyl-methacrylate (PMMA) and polyvinyl chloride (PVC)). Selectivity of the technique to the detection of 4-MMC was evaluated by analysing a range of adulterated samples including mixtures containing caffeine, methylamphetamine, cathinone and paracetamol. Specificity based on tandem MS (MS/MS) was also demonstrated by analysing substances with the same molecular formula as 4-MMC. Accuracy (% RE) and precision (% RSD) of the method were found to be within 13% and 38%, respectively; and therefore the quantitative data provided by the DESI-MS method is limited compared to gas chromatography-mass spectrometry (GC-MS; accuracy < 13% and precision < 12%). The results suggest that DESI-MS can greatly aid in the rapid presumptive identification of 4-MMC and other similar novel drug analogues.
Su, D, Dou, S & Wang, G 2014, 'ChemInform Abstract: WS2@graphene Nanocomposites as Anode Materials for Na‐Ion Batteries with Enhanced Electrochemical Performances.', ChemInform, vol. 45, no. 26, pp. no-no.
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AbstractWS2@graphene nanocomposites, in which WS2 nanocrystals are uniformly anchored on graphene nanosheets, are prepared by ultrasonication (30 min) of an aqueous suspension of WCl6 and freshly prepared graphite oxide nanosheets followed by hydrothermal treatment in the presence of cysteine (autoclave, 200 °C, 12 h).
Su, D, Dou, S & Wang, G 2014, 'Mesocrystal Co3O4 nanoplatelets as high capacity anode materials for Li-ion batteries', Nano Research, vol. 7, no. 5, pp. 794-803.
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Faceted crystals with exposed highly reactive planes have attracted intensive investigations for applications. Herein, we demonstrate a general synthetic method to prepare mesocrystal Co3O4 with predominantly exposed {111} reactive facets by the in situ thermal decomposition from Co(OH)2 nanoplatelets. The mesocrystal feature was identified by field emission scanning electron microscopy, transmission electron microscopy, selected area electron diffraction, and N2 isotherm analyses. When applied as anode material in lithium-ion batteries, mesocrystal Co3O4 nanoplatelets delivered a high specific capacity and an outstanding high rate performance. The superior electrochemical performance should be ascribed to the predominantly exposed {111} active facets and highly accessible surfaces. This synthetic strategy could be extended to prepare other mesocrystal functional nanomaterials. [Figure not available: see fulltext.] © 2014 Tsinghua University Press and Springer-Verlag Berlin Heidelberg.
Su, D, Dou, S & Wang, G 2014, 'Single Crystalline Co3O4 Nanocrystals Exposed with Different Crystal Planes for Li-O2 Batteries', Scientific Reports, vol. 4, no. 1.
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Single crystalline Co3O4 nanocrystals exposed with different crystal planes were synthesised, including cubic Co3O 4 nanocrystals enclosed by {100} crystal planes, pseudo octahedral Co3O4 enclosed by {100} and {110} crystal planes, Co 3O4 nanosheets exposed by {110} crystal planes, hexagonal Co3O4 nanoplatelets exposed with {111} crystal planes, and Co3O4 nanolaminar exposed with {112} crystal planes. Well single crystalline features of these Co3O4 nanocrystals were confirmed by FESEM and HRTEM analyses. The electrochemical performance for Li-o2 batteries shows that Co3O4 nanocrystals can significantly reduce the discharge-charge over-potential via the effect on the oxygen evolution reaction (OER). From the comparison on their catalytic performances, we found that the essential factor to promote the oxygen evolution reactions is the surface crystal planes of Co3O4 nanocrystals, namely, crystal planes-dependent process. The correlation between different Co3O4 crystal planes and their effect on reducing charge-discharge over-potential was established: {100} < {110} < {112} < {111}.
Su, D, Dou, S & Wang, G 2014, 'WS2@graphene nanocomposites as anode materials for Na-ion batteries with enhanced electrochemical performances', Chemical Communications, vol. 50, no. 32, pp. 4192-4192.
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WS2@graphene nanocomposites were synthesized by a hydrothermal approach. When applied as anodes in Na-ion batteries, the WS 2@graphene nanocomposite exhibited a high reversible sodium storage capacity of about 590 mA h g-1. It also demonstrated excellent high rate performance and cyclability. © the Partner Organisations 2014.
Su, D, Xie, X & Wang, G 2014, 'Hierarchical Mesoporous SnO Microspheres as High Capacity Anode Materials for Sodium‐Ion Batteries', Chemistry – A European Journal, vol. 20, no. 11, pp. 3192-3197.
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AbstractMesoporous SnO microspheres were synthesised by a hydrothermal method using NaSO4 as the morphology directing agent. Field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and high‐resolution transmission electron microscopy (HRTEM) analyses showed that SnO microspheres consist of nanosheets with a thickness of about 20 nm. Each nanosheet contains a mesoporous structure with a pore size of approximately 5 nm. When applied as anode materials in Na‐ion batteries, SnO microspheres exhibited high reversible sodium storage capacity, good cyclability and a satisfactory high rate performance. Through ex situ XRD analysis, it was found that Na+ ions first insert themselves into SnO crystals, and then react with SnO to generate crystalline Sn, followed by Na–Sn alloying with the formation of crystalline NaSn2 phase. During the charge process, there are two slopes corresponding to the de‐alloying of Na–Sn compounds and oxidisation of Sn, respectively. The high sodium storage capacity and good electrochemical performance could be ascribed to the unique hierarchical mesoporous architecture of SnO microspheres.
Su, D, Xie, X, Dou, S & Wang, G 2014, 'CuO single crystal with exposed {001} facets - A highly efficient material for gas sensing and Li-ion battery applications', Scientific Reports, vol. 4, no. 1.
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Single crystal copper oxide nanoplatelets with a high percentage of {001} facets were synthesized by a facile hydrothermal approach. The as-prepared materials were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, and high resolution transmission microscopy. Via density functional theory calculations, it was found that the {001} facets are active crystal planes. When the single crystal CuO nanoplatelets were applied as an anode material in Li-ion batteries, they demonstrated outstanding electrochemical performance with high lithium storage capacity, satisfactory cyclability, and excellent high rate capacity. When used as a sensing material in gas sensors, they exhibited a superior sensitivity towards toxic and flammable gases.
Su, D, Xie, X, Munroe, P, Dou, S & Wang, G 2014, 'Mesoporous hexagonal Co3O4 for high performance lithium ion batteries', Scientific Reports, vol. 4, no. 1.
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© 2014 Macmillan Publishers Limited. Mesoporous Co3O4 nanoplates were successfully prepared by the conversion of hexagonal β-Co(OH) 2 nanoplates. TEM, HRTEM and N2 sorption analysis confirmed the facet crystal structure and inner mesoporous architecture. When applied as anode materials for lithium storage in lithium ion batteries, mesoporous Co3O4 nanocrystals delivered a high specific capacity. At 10 C current rate, as-prepared mesoporous Co3O4 nanoplates delivered a specific capacity of 1203 mAh/g at first cycle and after 200 cycles it can still maintain a satisfied value (330 mAh/g). From ex-situ TEM, SAED and FESEM observation, it was found that mesoporous Co3O4 nanoplates were reduced to Li2O and Co during the discharge process and re-oxidised without losing the mesoporous structure during charge process. Even after 100 cycles, mesoporous Co3O4 crystals still preserved their pristine hexagonal shape and mesoporous nanostructure.
Su, DW, Dou, SX & Wang, GX 2014, 'Hierarchical orthorhombic V2O5 hollow nanospheres as high performance cathode materials for sodium-ion batteries', JOURNAL OF MATERIALS CHEMISTRY A, vol. 2, no. 29, pp. 11185-11194.
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Vanadyl ethylene glycolate hollow hierarchical nanospheres were synthesized via a template-free polyolinduced solvothermal process. After sintering, vanadium pentoxide (V2O5) with well-preserved spherical structures was obtained. Refined X-ray diffraction and transmission electron microscopy analyses identified that the V2O5 hollow nanospheres were constructed from hierarchical nanocrystals with predominantly exposed {110} crystal planes. When applied as cathode materials for sodium-ion batteries (Na-ion batteries), the V2O5 hollow nanospheres delivered a specific discharge capacity of ~150 mA h g-1, which is equal to one Na+ ion insertion per V2O5 formula unit. Theoretical modelling on the volume expansion and stress evolution on Na+ ion insertion revealed that the prolonged cycling stability could be ascribed to the porous hollow spherical architecture. Furthermore, the exposed {110} facets of V2O5 nanocrystals with two-dimensional diffusion paths for Na+ ion intercalation also contribute to high rate capacity and excellent cycling performance.
Sun, B, Huang, X, Chen, S, Munroe, P & Wang, G 2014, 'Porous Graphene Nanoarchitectures: An Efficient Catalyst for Low Charge-Overpotential, Long Life, and High Capacity Lithium-Oxygen Batteries', NANO LETTERS, vol. 14, no. 6, pp. 3145-3152.
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The electrochemical performance of lithium-oxygen (Li-O2) batteries awaits dramatic improvement in the design of porous cathode electrodes with sufficient spaces to accommodate the discharge products and discovery of effective cathode catalysts to promote both oxygen reduction reactions and oxygen evolution reactions. Herein, we report the synthesis of porous graphene with different pore size architectures as cathode catalysts for Li-O2 batteries. Porous graphene materials exhibited significantly higher discharge capacities than that of nonporous graphene. Furthermore, porous graphene with pore diameter around 250 nm showed the highest discharge capacity among the porous graphene with the small pores (about 60 nm) and large pores (about 400 nm). Moreover, we discovered that addition of ruthenium (Ru) nanocrystals to porous graphene promotes the oxygen evolution reaction. The Ru nanocrystal-decorated porous graphene exhibited an excellent catalytic activity as cathodes in Li-O2 batteries with a high reversible capacity of 17 700 mA h g-1, a low charge/discharge overpotential (about 0.355 V), and a long cycle life up to 200 cycles (under the curtaining capacity of 1000 mAh g-1). The novel porous graphene architecture inspires the development of high-performance Li-O2 batteries. © 2014 American Chemical Society.
Sun, B, Huang, X, Chen, S, Zhang, J & Wang, G 2014, 'An optimized LiNO3/DMSO electrolyte for high-performance rechargeable Li-O-2 batteries', RSC ADVANCES, vol. 4, no. 22, pp. 11115-11120.
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Finding stable electrolytes is essential to address the poor cycling capability of current rechargeable non-aqueous Li-O2 batteries. An optimized dimethyl sulfoxide (DMSO) based electrolyte using lithium nitrate (LiNO3) as the lithium salt has been first investigated for rechargeable Li-O2 batteries. The charge over-potential of Li-O 2 batteries with LiNO3/DMSO electrolyte is 0.42 V lower than that of batteries with LiClO4/DMSO electrolyte. The Li-O 2 batteries with LiNO3/DMSO electrolyte also showed excellent high C-rate performance and good cycling stability. © 2014 The Royal Society of Chemistry.
Sun, B, Huang, X, Chen, S, Zhao, Y, Zhang, J, Munroe, P & Wang, G 2014, 'Hierarchical macroporous/mesoporous NiCo2O4 nanosheets as cathode catalysts for rechargeable Li-O-2 batteries', JOURNAL OF MATERIALS CHEMISTRY A, vol. 2, no. 30, pp. 12053-12059.
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The key factor to improve the electrochemical performance of Li-O 2 batteries is to find bi-functional cathode catalysts to promote the oxygen reduction and evolution reactions. Despite tremendous effects, developing cathode catalysts with high activity remains a great challenge. Herein, we report the synthesis of hierarchical macroporous/mesoporous NiCo 2O4 nanosheets as an effective cathode catalyst for Li-O2 batteries. The hierarchical porous catalyst was synthesized by a hydrothermal method, followed by low temperature calcination. SEM and TEM observations clearly present that the as-prepared NiCo2O4 nanosheets showed a hierarchical porous structure with mesopores distributed through the surface of NiCo2O4 nanosheets and macropores formed between the crumpled nanosheets. When investigating as the cathode catalyst in Li-O2 batteries, the as-prepared NiCo2O 4 nanosheets exhibited higher reversible capacity, lower charge/discharge overpotential, and better cycling stability than those of pristine carbon black. The enhanced electrochemical performance of NiCo 2O4 nanosheets should be attributed not only to the high catalytic activity of NiCo2O4 towards oxygen reduction reaction and oxygen evolution reaction, but also to the novel hierarchical porous structure of NiCo2O4. This journal is © the Partner Organisations 2014.
Supansomboon, S, Porkovich, A, Dowd, A, Arnold, MD & Cortie, MB 2014, 'Effect of Precursor Stoichiometry on the Morphology of Nanoporous Platinum Sponges', ACS APPLIED MATERIALS & INTERFACES, vol. 6, no. 12, pp. 9411-9417.
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Tahir, M, Cao, C, Butt, FK, Butt, S, Idrees, F, Ali, Z, Aslam, I, Tanveer, M, Mahmood, A & Mahmood, N 2014, 'Large scale production of novel g-C3N4 micro strings with high surface area and versatile photodegradation ability', CrystEngComm, vol. 16, no. 9, pp. 1825-1825.
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Tahir, M, Cao, C, Mahmood, N, Butt, FK, Mahmood, A, Idrees, F, Hussain, S, Tanveer, M, Ali, Z & Aslam, I 2014, 'Multifunctional g-C3N4 Nanofibers: A Template-Free Fabrication and Enhanced Optical, Electrochemical, and Photocatalyst Properties', ACS Applied Materials & Interfaces, vol. 6, no. 2, pp. 1258-1265.
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Tanveer, M, Cao, C, Aslam, I, Ali, Z, Idrees, F, Khan, WS, Butt, FK, Tahir, M & Mahmood, A 2014, 'Facile Synthesis of CuS Nanostructures: Structural, Optical and Photocatalytic Properties', Science of Advanced Materials, vol. 6, no. 12, pp. 2694-2701.
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Teng, Q, Bai, J, Zhu, J & Guo, Y 2014, 'Current sensorless model predictive torque control based on adaptive backstepping observer for PMSM drives', WSEAS Transactions on Systems, vol. 13, no. 1, pp. 187-202.
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A novel adaptive backstepping observer is proposed and model predictive torque control (MPTC) strategy is considered for three-phase permanent magnet synchronous motor (PMSM) drives without any current sensor. Generally, instantaneous stator currents are required for successful operation of MPTC. If the stator current sensors fail, the most common technique for reconstructing stator currents mainly focuses on using information from a single current sensor in the DC-link of an inverter. Nevertheless, the existence of immeasurable regions in the output voltage hexagon results in that the three-phase currents will not be reliably detected since one or more of the active state vectors are not applied long enough to insure accurate measurements. In addition, the technique may suffer from the very noisy of DC-link current feedback. To avoid these drawbacks, making use of the technique of adaptive backstepping, a novel observer is proposed. The designed observer can be capable of concurrent estimation of stator currents and resistance under the assumption that rotor speed and inverter output voltage as well as DC-link voltage are available for measurement. Stability and convergence of the observer are analytically verified based on Lyapunov stability theory. In order to reduce the torque & flux ripples and improve drives control performance, MPTC strategy is employed. The proposed algorithm is less complicated and its implement is relatively easy. It can ensure that the whole drives system achieves satisfactory torque & speed control and strong robustness. Extensive simulation validates the feasibility and effectiveness of the proposed scheme.
Tian, H, Zhang, XL, Scott, J, Ng, C & Amal, R 2014, 'TiO2-supported copper nanoparticles prepared via ion exchange for photocatalytic hydrogen production', J. Mater. Chem. A, vol. 2, no. 18, pp. 6432-6438.
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Cu/TiO2 synthesized through ion exchange provides finer, more highly dispersed metallic copper deposits, displaying a ∼44% greater hydrogen generation capacity than WI Cu/TiO2 prepared using wet impregnation. The difference in activity was maintained over repeated reaction cycles.
Ton-That, C, Lem, LLC, Phillips, MR, Reisdorffer, F, Mevellec, J, Nguyen, T-P, Nenstiel, C & Hoffmann, A 2014, 'Shallow carrier traps in hydrothermal ZnO crystals', NEW JOURNAL OF PHYSICS, vol. 16, pp. 1-14.
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Native and hydrogen-plasma induced shallow traps in hydrothermally grown ZnO crystals have been investigated by charge-based deep level transient spectroscopy, photoluminescence and cathodoluminescence microanalysis. The as-grown ZnO exhibits a trap state at 23 meV, while H-doped ZnO produced by plasma doping shows two levels at 22 meV and 11 meV below the conduction band. As-grown ZnO displays the expected thermal decay of bound excitons with increasing temperature from 7 K, while we observed an anomalous behaviour of the excitonic emission in H-doped ZnO, in which its intensity increases with increasing temperature in the range 140-300 K. Based on a multitude of optical results, a qualitative model is developed which explains the Y line structural defects, which act as an electron trap with an activation energy of 11 meV, being responsible for the anomalous temperature-dependent cathodoluminescence of H-doped ZnO. © 2014 IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.
Traut-Johnstone, T, Kriel, FH, Hewer, R & Williams, DBG 2014, '4-(3-Azaniumylpropyl)morpholin-4-ium chloride hydrogen oxalate: an unusual example of a dication with different counter-anions', Acta Crystallographica Section C Structural Chemistry, vol. 70, no. 12, pp. 1121-1124.
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The mixed organic–inorganic title salt, C7H18N2O2+·C2HO4−·Cl−, forms an assembly of ionic components which are stabilized through a series of hydrogen bonds and charge-assisted intermolecular interactions. The title assembly crystallizes in the monoclinicC2/cspace group withZ= 8. The asymmetric unit consists of a 4-(3-azaniumylpropyl)morpholin-4-ium dication, a hydrogen oxalate counter-anion and an inorganic chloride counter-anion. The organic cations and anions are connected through a network of N—H...O, O—H...O and C—H...O hydrogen bonds, forming several intermolecular rings that can be described by the graph-set notationsR33(13),R21(5),R12(5),R21(6),R23(6),R22(8) andR33(9). The 4-(3-azaniumylpropyl)morpholin-4-ium dications are interconnected through N—H...O hydrogen bonds, formingC(9) chains that run diagonally along theabface. Furthermore, the hydrogen oxalate anions are interconnectedviaO—H...O hydrogen bonds, forming head-to-tailC(5) chains along the crystallographicbaxis. The two types of chains are linked through additional N—H...O and O—H...O hydrogen bonds, and the hydrogen oxalate ch...
Tshivhase, M & Williams, DBG 2014, 'Color-Coded Ligands: Tracking the Catalyst using Highly Pigmented Porphyrazine Ligands in Biphasic Reactions', Organometallics, vol. 33, no. 24, pp. 7023-7026.
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© 2014 American Chemical Society. We demonstrate the concept that highly colored imidazolium porphyrazine ligands and complexes may be useful for visualizing the location of a catalyst and/or ligand. This was analytically demonstrated by the application of UV-vis spectrophotometry to detect the ligand and ICP-OES spectroscopy for quantification of the Pd in the biphasic systems. In the first instance, a toluene/water system was used, in which the complex and ligand preferred the organic phase. Water-soluble substrates were made to react under these conditions by employing the complexes as catalysts in Heck and Suzuki C-C bond forming reactions. In the second instance, an ionic liquid containing biphasic mixture was used, in which the ligand/catalyst was retained in the ionic liquid. Catalyst recycling experiments were met with limited success.
Ung, AT, Williams, SG, Angeloski, A, Ashmore, J, Kuzhiumparambil, U, Bhadbhade, M & Bishop, R 2014, 'Formation of 3-azabicyclo[3.3.1]non-3-enes: imino amides vs. imino alkenes', MONATSHEFTE FUR CHEMIE, vol. 145, no. 6, pp. 983-992.
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An effective method for synthesising alkaloidlike compounds containing the 3-azabicyclo[3.3.1]non-3-ene core structure was successfully carried out in a stereoselective manner via the bridged-Ritter reactions. Important optically active 6-alkyl(aryl)amido-4-alkyl( aryl)-2,2,6-trimethyl-3-azabicyclo[3.3.1]non-3-enes (imino amides) and 4-alkyl(aryl)-2,2,6-trimethyl-3-azabicyclo[3.3.1]nona-3,6-dienes (imino alkenes) were obtained in one step from (-)-b-pinene and the respective nitriles in the presence of concentrated H2SO4. The relative compositions of these products were controlled by varying the reaction conditions. Kinetic studies were conducted to enable a mechanistic understanding of the reaction pathways.
Wang, B, Wen, Y, Ye, D, Yu, H, Sun, B, Wang, G, Hulicova-Jurcakova, D & Wang, L 2014, 'Dual Protection of Sulfur by Carbon Nanospheres and Graphene Sheets for Lithium- Sulfur Batteries', CHEMISTRY-A EUROPEAN JOURNAL, vol. 20, no. 18, pp. 5224-5230.
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Well-confined elemental sulfur was implanted into a stacked block of carbon nanospheres and graphene sheets through a simple solution process to create a new type of composite cathode material for lithium-sulfur batteries. Transmission electron microscopy and elemental mapping analysis confirm that the as-prepared composite material consists of graphene-wrapped carbon nanospheres with sulfur uniformly distributed in between, where the carbon nanospheres act as the sulfur carriers. With this structural design, the graphene contributes to direct coverage of sulfur to inhibit the mobility of polysulfides, whereas the carbon nanospheres undertake the role of carrying the sulfur into the carbon network. This composite achieves a high loading of sulfur (64.2 wt %) and gives a stable electrochemical performance with a maximum discharge capacity of 1394 mAh g-1 at a current rate of 0.1 C as well as excellent rate capability at 1 C and 2 C. The improved electrochemical properties of this composite material are attributed to the dual functions of the carbon components, which effectively restrain the sulfur inside the carbon nano-network for use in lithium-sulfur rechargeable batteries. Sulfur sandwich: A new type of sandwiched carbon network, consisting of graphene-wrapped carbon nanospheres coated with sulfur (82.7 wt % sulfur) were designed as a cathode material for lithium-sulfur rechargeable batteries (see scheme, CS=carbon sphere, GO=graphene oxide). The composite material exhibits a high specific discharge capacity of 1394 mAh g-1 at 0.1 C, excellent cycling stability for 100 cycles, and high rate performance at 1 C and 2 C. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Wei, Y, Chen, S, Su, D, Sun, B, Zhu, J & Wang, G 2014, '3D mesoporous hybrid NiCo2O4@graphene nanoarchitectures as electrode materials for supercapacitors with enhanced performances', JOURNAL OF MATERIALS CHEMISTRY A, vol. 2, no. 21, pp. 8103-8109.
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3D mesoporous hybrid NiCo2O4@graphene nanoarchitectures were successfully synthesized by a combination of freeze drying and hydrothermal reaction. Field-emission scanning electron microscopy (FESEM) and TEM analyses revealed that the NiCo2O 4@graphene nanostructures consist of a hierarchical mesoporous sheet-on-sheet nanoarchitecture with a high specific surface area of 194 m 2 g-1. Ultrathin NiCo2O4 nanosheets, with a thickness of a few nanometers and mesopores ranging from 2 to 5 nm, were wrapped in graphene nanosheets and hybrid nanoarchitectures were formed. When applied as electrode materials in supercapacitors, the hybrid NiCo 2O4@graphene nanosheets exhibited a high capacitance of 778 F g-1 at a current density of 1 A g-1, and an excellent cycling performance extending to 10000 cycles at a high current density of 10 A g-1. This journal is © the Partner Organisations 2014.
Williams, DBG, George, MJ & Marjanovic, L 2014, 'Rapid Detection of Atrazine and Metolachlor in Farm Soils: Gas Chromatography–Mass Spectrometry-Based Analysis Using the Bubble-in-Drop Single Drop Microextraction Enrichment Method', Journal of Agricultural and Food Chemistry, vol. 62, no. 31, pp. 7676-7681.
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Tracking of metolachlor and atrazine herbicides in agricultural soils, from spraying through to harvest, was conducted using our recently reported 'bubble-in-drop single-drop microextraction' method. The method showed good linearity (R2 = 0.999 and 0.999) in the concentration range of 0.01-1.0 ng/mL with LOD values of 0.01 and 0.02 ng/mL for atrazine and metolachlor, respectively. Sonication methods were poor at releasing these herbicides from the soil matrixes, while hot water extraction readily liberated them, providing an efficient accessible alternative to sonication techniques. Good recoveries of 97% and 105% were shown for atrazine and metolachlor, respectively, from the soil. The spiking protocol was also investigated, resulting in a traceless spiking method. We demonstrate a very sensitive technique by which to assess, for example, the length of residence of pesticides in given soils and thus risk of exposure. © 2014 American Chemical Society.
Wood, LK & Langford, SJ 2014, 'Motor Neuron Disease: A Chemical Perspective', Journal of Medicinal Chemistry, vol. 57, no. 15, pp. 6316-6331.
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Xie, X, Su, D, Chen, S, Zhang, J, Dou, S & Wang, G 2014, 'SnS2 Nanoplatelet@Graphene Nanocomposites as High‐Capacity Anode Materials for Sodium‐Ion Batteries', Chemistry – An Asian Journal, vol. 9, no. 6, pp. 1611-1617.
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AbstractNa‐ion batteries have been attracting intensive investigations as a possible alternative to Li‐ion batteries. Herein, we report the synthesis of SnS2 nanoplatelet@graphene nanocomposites by using a morphology‐controlled hydrothermal method. The as‐prepared SnS2/graphene nanocomposites present a unique two‐dimensional platelet‐on‐sheet nanoarchitecture, which has been identified by scanning and transmission electron microscopy. When applied as the anode material for Na‐ion batteries, the SnS2/graphene nanosheets achieved a high reversible specific sodium‐ion storage capacity of 725 mA h g−1, stable cyclability, and an enhanced high‐rate capability. The improved electrochemical performance for reversible sodium‐ion storage could be ascribed to the synergistic effects of the SnS2 nanoplatelet/graphene nanosheets as an integrated hybrid nanoarchitecture, in which the graphene nanosheets provide electronic conductivity and cushion for the active SnS2 nanoplatelets during Na‐ion insertion and extraction processes.
Xie, X, Su, D, Huang, X, Dou, SX & Wang, G 2014, 'Solvothermal Synthesis of Co3S4/Graphene Nanoassemblies As Anode Materials for Lithium-Ion Batteries', ECS Meeting Abstracts, vol. MA2014-04, no. 2, pp. 310-310.
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Co3S4/graphene nanoassemblies were synthesized by a facile solvothermal approach, in which bifunctional dimethyl sulfoxide served as both solvent and sulfur-source. Structural characterizations reveal an intimate contact between Co3S4 and graphene matrix. When employed as anode materials for lithium-ion batteries, the Co3S4/graphene nanoassemblies exhibited good electrochemical performance, including a high reversible capacity of 1085 mAh/g, good cyclability and excellent rate capability. Compared to bare Co3S4 and graphene, the lithium-ion storage performance has been significantly improved. The improved electrochemical performance for reversible lithium-ion storage could be ascribed to the synergistic effects of the Co3S4/graphene nanoassemblies as an integrated hybrid nanoarchitecture, in which graphene nanosheets provide electronic conductivity, serve as the homogeneous dispersive agent and offer buffer layers for the active Co3S4 during lithium-ion insertion and extraction processes.
Xie, X, Su, D, Sun, B, Zhang, J, Wang, C & Wang, G 2014, 'Synthesis of Single-Crystalline Spinel LiMn2O4 Nanorods for Lithium-Ion Batteries with High Rate Capability and Long Cycle Life', CHEMISTRY-A EUROPEAN JOURNAL, vol. 20, no. 51, pp. 17125-17131.
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© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. The long-standing challenge associated with capacity fading of spinel LiMn2O4 cathode material for lithiumion batteries is investigated. Single-crystalline spinel LiMn2O4 nanorods were successfully synthesized by a template-engaged method. Porous Mn3O4 nanorods were used as selfsacrificial templates, into which LiOH was infiltrated by a vacuum-assisted impregnation route. When used as cathode materials for lithium-ion batteries, the spinel LiMn2O4 nanorods exhibited superior long cycle life owing to the one-dimensional nanorod structure, single-crystallinity, and Li-rich effect. LiMn2O4 nanorods retained 95.6% of the initial capacity after 1000 cycles at 3C rate. In particular, the nanorod morphology of the spinel LiMn2O4 was well-preserved after a long-term cycling, suggesting the ultrahigh structural stability of the single crystalline spinel LiMn2O4 nanorods. This result shows the promising applications of single-crystalline spinel LiMn2O4 nanorods as cathode materials for lithium-ion batteries with high rate capability and long cycle life.
Yang, Q, Li, Y, Zhao, Z, Zhu, L, Luo, Y & Zhu, J 2014, 'Design of a 3-D Rotational Magnetic Properties Measurement Structure for Soft Magnetic Materials', IEEE Transactions on Applied Superconductivity, vol. 24, no. 3, pp. 1-4.
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Yiying Wei, Jianguo Zhu & Guoxiu Wang 2014, 'High-Specific-Capacitance Supercapacitor Based on Vanadium Oxide Nanoribbon', IEEE Transactions on Applied Superconductivity, vol. 24, no. 5, pp. 1-4.
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Younas, H, Qazi, IA, Hashmi, I, Ali Awan, M, Mahmood, A & Qayyum, HA 2014, 'Visible light photocatalytic water disinfection and its kinetics using Ag-doped titania nanoparticles', Environmental Science and Pollution Research, vol. 21, no. 1, pp. 740-752.
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Zhan, Y, Guo, Y, Zhu, J & Li, L 2014, 'Current short circuit implementation for performance improvement and lifetime extension of proton exchange membrane fuel cell', Journal of Power Sources, vol. 270, pp. 183-192.
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Zhan, Y, Guo, Y, Zhu, J & Li, L 2014, 'Natural degradation and stimulated recovery of a proton exchange membrane fuel cell', International Journal of Hydrogen Energy, vol. 39, no. 24, pp. 12849-12858.
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Zhang, H, Xu, W, Wang, S, Huangfu, Y, Wang, G & Zhu, J 2014, 'Optimum Design of Rotor for High-Speed Switched Reluctance Motor Using Level Set Method', IEEE Transactions on Magnetics, vol. 50, no. 2, pp. 765-768.
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This paper presents a novel rotor structure optimized by using the level set method (LSM) to improve the static torque characteristics of a two-phase 4/2 high-speed switched reluctance motor. The magnetic equivalent circuit approach is used to analyze the influence factors on the static torque. The inner material boundary contained in the rotor saliency, which will be optimized, is implicitly represented by an embedded level set function. The evolution of the inner material boundaries is driven by the normal velocity derived through sensitivity analysis and adjoint variable computation. Optimal rotor configuration produces the nonuniform distribution of magnetic flux density in the air gap at aligned position, which can make the ratio of maximum and minimum inductances increased. High-permeability material is applied to enhance the mean torque. In order to achieve the optimal static torque, the strategy combining finite-element electromagnetic computation with LSM is conducted to optimize the rotor saliency at different rotor positions. The comparison of the optimized rotor configuration using LSM with that using density-based method suggests that the optimized rotor structure obtained using this presented method is easier to implement.
Zhang, Y, Hu, J & Zhu, J 2014, 'Three-Vectors-Based Predictive Direct Power Control of the Doubly Fed Induction Generator for Wind Energy Applications', IEEE Transactions on Power Electronics, vol. 29, no. 7, pp. 3485-3500.
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