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排序方式: 共有1587条查询结果,搜索用时 171 毫秒
91.
Alicja Nejman Anna Baranowska-Korczyc Katarzyna Ranoszek-Soliwoda Izabela Jasiska Grzegorz Celichowski Magorzata Cielak 《Molecules (Basel, Switzerland)》2022,27(6)
New functionalization methods of meta- and para-aramid fabrics with silver nanowires (AgNWs) and two silanes (3-aminopropyltriethoxysilane (APTES)) and diethoxydimethylsilane (DEDMS) were developed: a one-step method (mixture) with AgNWs dispersed in the silane mixture and a two-step method (layer-by-layer) in which the silanes mixture was applied to the previously deposited AgNWs layer. The fabrics were pre-treated in a low-pressure air radio frequency (RF) plasma and subsequently coated with polydopamine. The modified fabrics acquired hydrophobic properties (contact angle ΘW of 112–125°). The surface free energy for both modified fabrics was approximately 29 mJ/m2, while for reference, meta- and para-aramid fabrics have a free energy of 53 mJ/m2 and 40 mJ/m2, respectively. The electrical surface resistance (Rs) was on the order of 102 Ω and 104 Ω for the two-step and one-step method, respectively. The electrical volume resistance (Rv) for both modified fabrics was on the order of 102 Ω. After UV irradiation, the Rs did not change for the two-step method, and for the one-step method, it increased to the order of 1010 Ω. The specific strength values were higher by 71% and 63% for the meta-aramid fabric and by 102% and 110% for the para-aramid fabric for the two-step and one-step method, respectively, compared to the unmodified fabrics after UV radiation. 相似文献
92.
通过对共享保护算法的深入分析,使用K条最短路和迭代思想的方法,提出了两种共享风险链路组不相关的共享保护算法,并在仿真平台上对两种算法的性能进行了仿真.KWFF算法借鉴了传统的K条最短路策略,并且在每一个波长平面上,都对新到业务进行了K条工作路由的计算,极大挖掘了网络中潜在的波长资源.而IFF算法由于引入了迭代的思想,避免了共享风险链路组问题中,所特别有“陷阱”问题的出现,并且利用两套权重计算公式,在计算工作路由和保护路由的时候,充分考虑了网络资源的实时变化情况.通过仿真数据可以看到,与以往算法相比,KWFF和IFF算法大大降低了网络阻塞率,并且提高了网络资源的使用效率. 相似文献
93.
Wen Xing Chaoling Wen Deguo Wang Hui Shao Chunhong Liu Chunling He Opeyemi Joshua Olatunji 《Molecules (Basel, Switzerland)》2022,27(7)
Doxorubicin (DXB) is one of the most commonly used anticancer agents for treating solid and hematological malignancies; however, DXB-induced cardiorenal toxicity presents a limiting factor to its clinical usefulness in cancer patients. Costunolide (COST) is a naturally occurring sesquiterpene lactone with excellent anti-inflammatory, antioxidant and antiapoptotic properties. This study evaluated the effect of COST on DXB-induced cardiorenal toxicity in rats. Rats were orally treated with COST for 4 weeks and received weekly 5 mg/kg doses of DXB for three weeks. Cardiorenal biochemical biomarkers, lipid profile, oxidative stress, inflammatory cytokines, histological and immunohistochemical analyses were evaluated. DXB-treated rats displayed significantly increased levels of lipid profiles, markers of cardiorenal dysfunction (aspartate aminotransferase, creatine kinase, lactate dehydrogenase, troponin T, blood urea nitrogen, uric acid and creatinine). In addition, DXB markedly upregulated cardiorenal malondialdehyde, tumor necrosis factor-α, interleukin-1β, interleukin-6 levels and decreased glutathione, superoxide dismutase and catalase activities. COST treatment significantly attenuated the aforementioned alterations induced by DXB. Furthermore, histopathological and immunohistochemical analyses revealed that COST ameliorated the histopathological features and reduced p53 and myeloperoxidase expression in the treated rats. These results suggest that COST exhibits cardiorenal protective effects against DXB-induced injury presumably via suppression of oxidative stress, inflammation and apoptosis. 相似文献
94.
Akikazu Matsumoto Yoshinori Sano Masahiro Yoshioka Takayuki Otsu 《Journal of polymer science. Part A, Polymer chemistry》1996,34(2):291-299
The radical polymerization of dialkyl fumarates (DRF) bearing various ester alkyl groups was kinetically studied. The propagation and termination rate constants were determined using electron spin resonance (ESR) spectroscopy. The introduction of the bulky ester alkyl groups such as a tert-butyl group decreased the termination rate constant as expected. However, it has also been revealed that the bulky groups promote propagation despite the steric repulsion. The propagation rate and mechanism are discussed in relation to the propagation manner, i.e., tacticity of the polymer. © 1996 John Wiley & Sons, Inc. 相似文献
95.
Yoshihiro Itoh Masamitsu Inoue Akira Hachimori 《Journal of polymer science. Part A, Polymer chemistry》1996,34(1):89-93
Alternating and random copolymers of 2-(9-carbazolyl)ethyl methacrylate with aromatic vinyl monomers were synthesized and their fluorescence properties were compared in good and poor solvents. Contraction of the polymer coils induced the hypochromic effect, i.e., the mutual interaction of the ground-state chromophores, but caused little quenching of their excited state. This is sharp in contrast with the vinyl-type of polymers, exhibiting large interactions in both the ground and excited states. Introduction of bulky groups on the comonomers in the alternating copolymers further suppressed these interactions. © 1996 John Wiley & Sons, Inc. 相似文献
96.
97.
Sodium metal anodes have attracted significant attention due to their high specific capacity,low redox potential and abundant resources.However,the dendrites and unstable solid electrolyte interphase(SEI)of sodium anodes restrict the development of sodium metal batteries.This review includes the recent progress on the Na anode protection in sodium metal batteries.The strategies are summarized as modified three-dimensional current collectors,artificial solid electrolyte interphases,and electrolyte modifications.Conclusions and perspectives are envisaged for the further understanding and development of Na metal anodes. 相似文献
98.
熵如力、能量和动量一样是物理学中一个重要概念,若能用一种通俗易懂的方法设计熵的教学,对文科物理的教学有重要意义.为此本文提出了一种通俗的熵的教法,这一教法不需要学生学习热力学第二定律也可以建立熵的概念.具体教学设计如下:通过日常生活例子引入熵的概念(也就是玻尔兹曼熵),设计两个例子让学生会计算熵,通过具体问题的讨论让学生充分理解熵的意义,通过一个实例由玻尔兹曼熵引入克劳修斯熵公式,设计一个演示实验强化教学效果,将熵与环境保护联系起来融入人文情怀,最后还强调了熵计算的不同层次.教学设计完全采用基于问题学习(PBL)的教学模式. 相似文献
99.
100.