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排序方式: 共有4821条查询结果,搜索用时 15 毫秒
41.
42.
Chunhua Han Xiaoji Ren Qidong Li Wen Luo Lei Huang Liang Zhou Liqiang Mai 《Nano Research》2018,11(3):1285-1293
Mixed transition metal oxides (MTMOs) have received intensive attention as promising anode materials for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). In this work, we demonstrate a facile one-step water-bath method for the preparation of graphene oxide (GO) decorated Fe2(MoO4)3 (FMO) microflower composite (FMO/GO), in which the FMO is constructed by numerous nanosheets. The resulting FMO/GO exhibits excellent electrochemical performances in both LIBs and SIBs. As the anode material for LIBs, the FMO/GO delivers a high capacity of 1,220 mAh·g–1 at 200 mA·g–1 after 50 cycles and a capacity of 685 mAh·g–1 at a high current density of 10 A·g–1. As the anode material for SIBs, the FMO/GO shows an initial discharge capacity of 571 mAh·g–1 at 100 mA·g–1, maintaining a discharge capacity of 307 mAh·g–1 after 100 cycles. The promising performance is attributed to the good electrical transport from the intimate contact between FMO and graphene oxide. This work indicates that the FMO/GO composite is a promising anode for high-performance lithium and sodium storage. 相似文献
43.
Zixuan Wang Dongzhao Hao Yuefei Wang Jinwu Zhao Jiaxing Zhang Xi Rong Jiaojiao Zhang Jiwei Min Wei Qi Rongxin Su Mingxia He 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(1):2204959
The self-assembly of peptidyl virus-like nanovesicles (pVLNs) composed of highly ordered peptide bilayer membranes that encapsulate the small interfering RNA (siRNA) is reported. The targeting and enzyme-responsive sequences on the bilayer's surface allow the pVLNs to enter cancer cells with high efficiency and control the release of genetic drugs in response to the subcellular environment. By transforming its structure in response to the highly expressed enzyme matrix metalloproteinase 7 (MMP-7) in cancer cells, it helps the siRNA escape from the lysosomes, resulting in a final silencing efficiency of 92%. Moreover, the pVLNs can serve as reconfigurable “Trojan horse” by transforming into membranes triggered by the MMP-7 and disrupting the cytoplasmic structure, thereby achieving synergistic anticancer effects and 96% cancer cell mortality with little damage to normal cells. The pVLNs benefit from their biocompatibility, targeting, and enzyme responsiveness, making them a promising platform for gene therapy and anticancer therapy. 相似文献
44.
针对巨量可选方案的群体决策问题,提出了一个新的基于参考点和投票规则的多目标粒子群优化算法。该算法把个体与参考点的支配关系或者距离作为一个重要因素,在选择引导者的锦标赛方法,局部最优更新规则,以及外部种群档案剪枝规则中都嵌入了基于支配关系或距离因素的投票规则,以找到群体决策解,并且提高搜索效率。仿真结果表明该算法有效。 相似文献
45.
46.
Colussi C Banfi C Brioschi M Tremoli E Straino S Spallotta F Mai A Rotili D Capogrossi MC Gaetano C 《Proteomics. Clinical applications》2010,4(1):71-83
Purpose: Histone Deacetylase Inhibitors (DI) ameliorates dystrophic muscle regeneration restoring muscular strength in the mdx mouse model of Duchenne muscular dystrophy (DMD). The further development of these compounds as drugs for DMD treatment is currently hampered by the lack of knowledge about DIs effect in large dystrophic animal models and that of suitable biomarkers to monitor their efficacy. Experimental design: In this study we applied proteomic analysis to identify differentially expressed proteins present in plasma samples from mdx mice treated with the Suberoylanilide hydroxamic acid (SAHA) and relative normal controls (WT). Results: Several differentially expressed proteins were identified between untreated wild type and mdx mice. Among these, fibrinogen, epidermal growth factor 2 receptor, major urinary protein and glutathione peroxidase 3 (GPX3) were constitutively up‐regulated in mdx, while complement C3, complement C6, gelsolin, leukaemia inhibitory factor receptor (LIFr), and alpha 2 macroglobulin were down‐regulated compared to WT mice. SAHA determined the normalization of LIFr and GPX3 protein level while apoliprotein E was de novo up‐regulated in comparison to vehicle‐treated mdx mice. Conclusions and clinical relevance: Collectively, these data unravel potential serological disease biomarkers of mdx that could be useful to monitor muscular dystrophy response to DI treatment. 相似文献
47.
针对电力系统经济负荷分配问题,提出一种有效的差分蜂群算法.受差分进化算法的启发,该算法基于差分进化操作改进了雇佣蜂的搜索方式,提高了探索能力和收敛速度.此外,提出一种有效的修复机制以保证新个体的可行性.该算法在带有阀点效应和多燃料特征的典型电力系统经济负荷分配问题上进行了测试.仿真结果验证了所提算法的有效性. 相似文献
48.
介绍了利用红外线的发射与接收所构成的光束保护系统。红外线的发射与接收形成一“安全网” ,利用其档光性能 ,可以实现安全防范功能。为提高系统抗干扰性能 ,采用调制的红外光线 ,经过信号处理 ,驱动继电器动作 ,从而实现报警和保护。重点阐述了光束保护系统的基本工作原理 ,并给出了主要硬件原理图。 相似文献
49.
已有ORACLE系统的性能调整优化 总被引:7,自引:0,他引:7
引起ORACLE应用系统效率低下的原因很复杂,而对ORACLE的优化过多集中于应用程序的设计优化,该文通过讨论和研究 Oracle服务器的特征和在逻辑、物理和变化上的特点,分析了造成 ORACLE系统性能低下的原因,并阐述了在不改动应用程序的情况下,提高、调整Oracle系统性能的一些原则和方法。 相似文献
50.
The static and impact fracture toughnesses of a polybutylene terephthalate/polycarbonate/impact modifier (PBT/PC/IM) blend
were studied at different temperatures. The static fracture toughness of the blend was evaluated via the specific fracture
work concept and the J-integral analysis. A comparison of these two analytical methods showed that the specific essential fracture work, W
e, was equivalent to the
obtained by the ASTM E813-81 procedure, representing the crack initiation resistance of the material. The discrepancy between
W
e and
of ASTM E813-89 was caused by the extra energy component in
consumed by a 0.2 mm crack growth. Impact fracture toughness was also analysed using the specific essential fracture work
approach. When the fracture was elastic, W
e was equivalent to the critical potential energy release rate, G
IC, obtained via LEFM analysis. Temperature and strain-rate effects on the fracture toughness were also studied. The increase
in impact toughness with temperature was attributed to two different toughening mechanisms, namely, the relaxation processes
of the rubbery particles and the parent polymers in a relatively low-temperature range and thermal blunting of the crack tip
at higher temperatures. The enhancement in static fracture toughness at temperatures below — 60 °C was thought to be caused
by plastic crack-tip blunting, but the monotonic reduction in yield stress was largely responsible for the toughness decreasing
with higher temperatures. The temperature-dependent fracture toughness data obtained in static tests could be horizontally
shifted to match roughly the data for the impact tests, indicating the existence of a time-temperature equivalence relationship. 相似文献