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Sijiang Hu Yu Li Yuhua Chen Jiming Peng Tengfei Zhou Wei Kong Pang Christophe Didier Vanessa K. Peterson Hongqiang Wang Qingyu Li Zaiping Guo 《Liver Transplantation》2019,9(34)
Li‐rich layered oxides (LLOs) can deliver almost double the capacity of conventional electrode materials such as LiCoO2 and LiMn2O4; however, voltage fade and capacity degradation are major obstacles to the practical implementation of LLOs in high‐energy lithium‐ion batteries. Herein, hexagonal La0.8Sr0.2MnO3?y (LSM) is used as a protective and phase‐compatible surface layer to stabilize the Li‐rich layered Li1.2Ni0.13Co0.13Mn0.54O2 (LM) cathode material. The LSM is Mn? O? M bonded at the LSM/LM interface and functions by preventing the migration of metal ions in the LM associated with capacity degradation as well as enhancing the electrical transfer and ionic conductivity at the interface. The LSM‐coated LM delivers an enhanced reversible capacity of 202 mAh g?1 at 1 C (260 mA g?1) with excellent cycling stability and rate capability (94% capacity retention after 200 cycles and 144 mAh g?1 at 5 C). This work demonstrates that interfacial bonding between coating and bulk material is a successful strategy for the modification of LLO electrodes for the next‐generation of high‐energy Li‐ion batteries. 相似文献
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Hoon‐Hee Ryu Kang‐Joon Park Dae Ro Yoon Assylzat Aishova Chong S. Yoon Yang‐Kook Sun 《Liver Transplantation》2019,9(44)
Substituting W for Al in the Ni‐rich cathode Li[Ni0.885Co0.10Al0.015]O2 (NCA89) produces Li[Ni0.9Co0.09W0.01]O2 (NCW90) with markedly reduced primary particle size. Particle size refinement considerably improves the cathode's cycling stability such that the NCW90 cathode retains 92% of its initial capacity after 1000 cycles (compared to 63% for NCA89), while the cathode produces a high initial discharge capacity of 231.2 mAh g?1 (at 0.1 C). Thus, the proposed NCW90 can deliver high energy density and a long battery lifetime simultaneously, unlike other Ni‐rich layered oxide cathodes. This unprecedented cycling stability is mainly attributed to a series of interparticular microfractures that absorb the anisotropic lattice strain caused by a deleterious phase transition near the charge end, thereby improving the cathode's resistance to fracture. Microcrack suppression preserves the mechanical integrity of the cathode particles during cycling and protects the particle interior from detrimental electrolyte attack. The proposed NCW90 cathode provides an improved material from which a new series of Ni‐rich layered cathode can be developed for next‐generation electric vehicles. 相似文献
84.
Jorge F. Genise Juan L. Farina Mariano Verde 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2013,46(4):480-489
The trace fossil Teisseirei barattinia, found in Cenozoic formations of Uruguay and Argentina, is an elongated chamber recognizable by its depressed cross‐section, antechamber, and its multi‐layered lining with an inner surface texture composed of densely packed sub‐rectangular to sub‐triangular pits. Our recent behavioural observations on larval and pupal stages of Sphingidae (Lepidoptera), particularly on Manduca rustica, suggest that Teisseirei barattinia is the pupation chamber of a sphinx moth. Last instar larvae of Manduca rustica, Eumorpha anchemolus and E. labruscae were placed in terraria to observe their burrowing behaviour and to recover pupation chambers. Chambers show depressed or plane convex cross‐sections as T. barattinia. The internal surface texture of walls is also similar to that of T. barattinia. The same pattern could be obtained experimentally by pressing the true legs of Manduca rustica larva against plasticine. The multi‐layered wall structure, shown by T. barattinia, is a new type of lining for insect trace fossils in palaeosols that result from soil packing combined with discharges of abundant liquid excretion by soft‐bodied larvae, as in the case of Manduca rustica. T. barattinia is the first trace fossil documented in palaeosols attributed to sphinx moths and supported by macro and micromorphological comparisons with extant pupation chambers. The shallow emplacement of moth pupation chambers in soils suggests that T. barattinia would be a good indicator of palaeosol upper horizons. 相似文献
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Yonghyun Cho Sanghan Lee Yongseok Lee Taeeun Hong Jaephil Cho 《Liver Transplantation》2011,1(5):821-828
In an attempt to overcome the problems associated with LiNiO2, the solid solution series of lithium nickel‐metal oxides, Li[Ni1–xMx]O2 (with M = Co, Mn, Al, Ti, Mg, etc.), have been investigated as favorable cathode materials for high‐energy and high‐power lithium‐ion batteries. However, along with the improvement in the electrochemical properties in Ni‐based cathode materials, the thermal stability has been a great concern, and thus violent reaction of the cathode with the electrolyte needs to be avoided. Here, we report a heterostructured Li[Ni0.54Co0.12Mn0.34]O2 cathode material which possesses both high energy and safety. The core of the particle is Li[Ni0.54Co0.12Mn0.34]O2 with a layered phase (R3‐m) and the shell, with a thickness of < 0.5 μm, is a highly stable Li1+x[CoNixMn2–x]2O4 spinel phase (Fd‐3m). The material demonstrates reversible capacity of 200 mAhg‐1 and retains 95% capacity retention under the most severe test condition of 60 °C. In addition, the amount of oxygen evolution from the lattice in the cathode with two heterostructures is reduced by 70%, compared to the reference sample. All these results suggest that the bulk Li[Ni0.54Co0.12Mn0.34]O2 consisting of two heterostructures satisfy the requirements for hybrid electric vehicles, power tools, and mobile electronics. 相似文献
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Mohd. Basyaruddin Abdul Rahman Noor Mona Md Yunus Mohd Zobir Hussein Raja Noor Zaliha Raja Abdul Rahman Abu Bakar Salleh Mahiran Basri 《Biocatalysis and Biotransformation》2013,31(3-4):233-239
Ni/Al-layered double hydroxides (Ni-LDHs) and Ni/Al-sodium dodecyl sulfonate layered double hydroxide nanocomposites (Ni-SDS-LDHs) with a molar ratio of Ni:Al (4:1) have been prepared by a co-precipitation (or salt-base) method. Their structures were determined using Powder X-Ray Diffractometer (PXRD) and the spectra showed that basal spacings for Ni-LDHs and Ni-SDS-LDHs synthesised were around 8.1?Å and 34.8?Å, respectively. Lipase from Candida rugosa was immobilised onto these advanced materials, by physical adsorption. The activity of immobilised lipase was investigated through esterification of palmitic acid and isopropyl alcohol in hexane. The effects of reaction temperature, thermostability, stability in organic solvent, operational stability, leaching and storage studies of the immobilised lipase were investigated. These biocatalysts exhibited higher activities than the native lipase with an optimum temperature of 40°C. Immobilised lipases showed higher storage stability than native lipase (up to 60 days) and during operational studies at 30°C for 5?h, more than 50% of its activity was retained. Leaching studies showed that physical adsorption is suitable for the attachment of enzymes onto LDHs. 相似文献
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Zinc‐Air Batteries: NiFe Layered Double Hydroxide Nanoparticles on Co,N‐Codoped Carbon Nanoframes as Efficient Bifunctional Catalysts for Rechargeable Zinc–Air Batteries (Adv. Energy Mater. 21/2017) 下载免费PDF全文
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The objective of present investigation was to develop venlafaxine hydrochloride-layered tablets for obtaining sustained drug
release. The tablets containing venlafaxine hydrochloride 150 mg were prepared by wet granulation technique using xanthan
gum in the middle layer and barrier layers. The granules and tablets were characterized. The in vitro drug dissolution study was conducted in distilled water. The tablets containing two lower strengths were also developed using
the same percentage composition of the middle layer. Kinetics of drug release was studied. The optimized batches were tested
for water uptake study. Radar diagrams are provided to compare the performance of formulated tablets with the reference products,
Effexor XR capsules. The granules ready for compression exhibited good flow and compressibility when xanthan gum was used
in the intragranular and extragranular fractions. Monolayer tablets failed to give the release pattern similar to that of
the reference product. The drug release was best explained by Weibull model. A unified Weibull equation was evolved to express
drug release from the formulated tablets. Lactose facilitated drug release from barrier layers. Substantial water uptake and
gelling of xanthan gum appears to be responsible for sustained drug release. The present study underlines the importance of
formulation factors in achieving same drug release pattern from three strengths of venlafaxine hydrochloride tablets. 相似文献
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