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1.
Scientometrics - The article published on 5 July 2021 is well-written and of interest. However, some improvements could be made, such as ten Tables/Figures can be shortened to highlight the focused... 相似文献
2.
Liangtao Yang Liang-Yin Kuo Juan Miguel López del Amo Prasant Kumar Nayak Katherine A. Mazzio Sebastian Maletti Daria Mikhailova Lars Giebeler Payam Kaghazchi Teófilo Rojo Philipp Adelhelm 《Advanced functional materials》2021,31(38):2102939
A known strategy for improving the properties of layered oxide electrodes in sodium-ion batteries is the partial substitution of transition metals by Li. Herein, the role of Li as a defect and its impact on sodium storage in P2-Na0.67Mn0.6Ni0.2Li0.2O2 is discussed. In tandem with electrochemical studies, the electronic and atomic structure are studied using solid-state NMR, operando XRD, and density functional theory (DFT). For the as-synthesized material, Li is located in comparable amounts within the sodium and the transition metal oxide (TMO) layers. Desodiation leads to a redistribution of Li ions within the crystal lattice. During charging, Li ions from the Na layer first migrate to the TMO layer before reversing their course at low Na contents. There is little change in the lattice parameters during charging/discharging, indicating stabilization of the P2 structure. This leads to a solid-solution type storage mechanism (sloping voltage profile) and hence excellent cycle life with a capacity of 110 mAh g-1 after 100 cycles. In contrast, the Li-free compositions Na0.67Mn0.6Ni0.4O2 and Na0.67Mn0.8Ni0.2O2 show phase transitions and a stair-case voltage profile. The capacity is found to originate from mainly Ni3+/Ni4+ and O2-/O2-δ redox processes by DFT, although a small contribution from Mn4+/Mn5+ to the capacity cannot be excluded. 相似文献
3.
Chil-Chyuan Kuo Hsueh-An Liu Chao-Ming Chang 《The International Journal of Advanced Manufacturing Technology》2020,106(9):3775-3785
Vacuum casting is one of the widely used methods for small-volume production of plastic parts. The main challenge of this method is to choose the optimal w 相似文献
4.
针对矿山18线南西翼矿体开采过程中存在的通风系统不完善、风量欠缺、污风无法及时排出等问题,运用风压平衡原理、网络优化技术、机站优化技术以及计算机网络模拟技术展开研究,拟定了3种可行的通风方案。经技术经济比较,确定了新掘18线905~855 m回风井(1.5 m),保留该井905 m 水平回风机站,并在855 m 水平新设1台K45 6 №12风机(18.5 kW)方案。数值模拟结果表明:18线南西翼通风系统总风量达到20.5 m3/s,井下风流的可调性和稳定性增强,为矿山的安全生产提供了有力保障。 相似文献
5.
Multifunctional 3D Patternable Drug‐Embedded Nanocarrier‐Based Interfaces to Enhance Signal Recording and Reduce Neuron Degeneration in Neural Implantation 下载免费PDF全文
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7.
Wu-An Kuo TingTing Hwang Wu A.C.-H. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2006,14(1):81-85
This paper presents a novel power-driven multiplication instruction-set design method for application-specific instruction-set processors (ASIPs). Based on a dual-and-configurable-multiplier structure, our proposed method devises a multiplication instruction set for low-power ASIPs. Our method exploits the execution sequences of multiplication instructions and effective bit widths of variables to reduce power consumed by redundant multiplication bits while minimizing the multiplication execution time. Experimental results on a set of DSP programs demonstrate that our proposed method achieves significant power reduction (up to 18.53%) and execution time improvement (up to 10.43%) with 18% area overhead. 相似文献
8.
Microstrip stepped impedance resonator bandpass filter with an extended optimal rejection bandwidth 总被引:2,自引:0,他引:2
Bandpass filters with an optimal rejection bandwidth are designed using parallel-coupled stepped impedance resonators (SIRs). The fundamental (f/sub o/) and higher order resonant harmonics of an SIR are analyzed against the length ratio of the high-Z and low-Z segments. It is found that an optimal length ratio can be obtained for each high-Z to low-Z impedance ratio to maximize the upper rejection bandwidth. A tapped-line input/output structure is exploited to create two extra transmission zeros in the stopband. The singly loaded Q(Q/sub si/) of a tapped SIR is derived. With the aid of Q/sub si/, the two zeros can be independently tuned over a wide frequency range. When the positions of the two zeros are purposely located at the two leading higher order harmonics, the upper rejection band can be greatly extended. Chebyshev bandpass filters with spurious resonances up to 4.4f/sub o/, 6.5f/sub o/, and 8.2f/sub o/ are fabricated and measured to demonstrate the idea. 相似文献
9.
H.P. Kuo P.C. KnightD.J. Parker A.S. BurbidgeM.J. Adams J.P.K. Seville 《Powder Technology》2003,132(1):1-9
The motion of sand particles close to a single moving blade was investigated using Positron Emission Particle Tracking (PEPT) during the period in which the free bed surface profile was evolving to an equilibrium shape. The area affected by the blade was divided into active and inactive regions and these were analysed separately. The characteristic heart-shape of the active region in the plan view was determined. An approximately 10-particle-diameter wide velocity transition zone is found between the two regions. While the tracer particle is in the inactive region moving away from the blade, the time dependence of the axial displacement is well described by a logarithmic relationship. The probability of particle movement towards the centre of the blade was quantified using a “central tendency” index. The calculated central tendency shows maxima at each side of the blade. The separation of the two maxima, which indicates the width of the active region, increases with fill level but is independent of rotational speed. 相似文献
10.
LC Niessen 《Canadian Metallurgical Quarterly》1993,53(2):115-118
In the past 5 years we have discovered 8 boys and 3 girls who suffer from fructose-1,6-bisphosphatase deficiency. Although they all showed the typical symptoms of the deficiency such as frequent vomiting, hypoglycemia, lactic acidosis, and hepatomegaly, the age at diagnosis varied from 2 months to 4 years. All the boys revealed the deficient enzyme activity in leukocytes but none of the girls. The liver biopsy was investigated in six patients to confirm the diagnosis. These results suggest the existence of tissue-specific isoenzymes for fructose-1,6-bisphosphatase possibly with a different gene origin. 相似文献