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101.
102.
The last decade has seen a growing interest in hybrid electrically conducting nanocomposites. This article aims to provide a detailed overview of the present status of research in carbon nanotube–polyaniline (CNT/PANI) composites, from processing to structural and property evaluations. CNT/PANI are synthesized by electrochemical and chemical processing. When chemical methods are used, the main challenge is to obtain processable CNT/PANI in the emeraldine salt (ES) form composites. Stable dispersions of ES–CNT in organic media are prepared using the post doping method, inverse emulsion polymerization, or ex situ polymerizations. On the contrary, stable water dispersions of CNT/ES are prepared using hydrophilization of a preformed CNT/ES composite, direct synthesis of micelle–CNT hybrid templates, interfacial polymerization, covalent functionalization of CNT with a water soluble polymer, or using electrostatic interactions between two oppositely charged ES and CNT aqueous colloids. Moreover, the strategies for the synthesis of ternary CNT/PANI composites incorporating noble metal nanoparticles, metal oxide, or graphene sheets are also presented and analyzed in depth. Finally, we give a review of potential applications, including chemical sensors, capacitors, fuel cells and electronic devices. 相似文献
103.
以余甘子提取液和圣女果汁为原料,通过乳酸菌发酵制得具有抗疲劳作用的余甘子圣女果复合发酵饮料.基于单因素实验结果,采用响应面分析法优化该复合发酵饮料的制备工艺,同时利用动物实验考察其对小鼠运动耐力的影响.结果 表明,最佳发酵工艺为:乳酸菌接种量0.6%、余甘子提取液与圣女果汁的体积比1:3、发酵温度45℃、发酵时间29.... 相似文献
104.
制氢转化炉炉顶衬里结构的改造设计 总被引:1,自引:0,他引:1
通过制氢转化炉炉顶衬里结构改造两种设计方案的介绍,说明折叠式耐火陶瓷纤维模块用于转化炉炉顶衬里的优点. 相似文献
105.
106.
Zamzam Awida Almog Bachar Hussam Saed Anton Gorodov Nathalie Ben-Califa Maria Ibrahim Albert Kolomansky Jennifer Ana Iden Liad Graniewitz Visacovsky Tamar Liron Sahar Hiram-Bab Michael Brines Yankel Gabet Drorit Neumann 《International journal of molecular sciences》2022,23(1)
The two erythropoietin (EPO) receptor forms mediate different cellular responses to erythropoietin. While hematopoiesis is mediated via the homodimeric EPO receptor (EPOR), tissue protection is conferred via a heteromer composed of EPOR and CD131. In the skeletal system, EPO stimulates osteoclast precursors and induces bone loss. However, the underlying molecular mechanisms are still elusive. Here, we evaluated the role of the heteromeric complex in bone metabolism in vivo and in vitro by using Cibinetide (CIB), a non-erythropoietic EPO analogue that exclusively binds the heteromeric receptor. CIB is administered either alone or in combination with EPO. One month of CIB treatment significantly increased the cortical (~5.8%) and trabecular (~5.2%) bone mineral density in C57BL/6J WT female mice. Similarly, administration of CIB for five consecutive days to female mice that concurrently received EPO on days one and four, reduced the number of osteoclast progenitors, defined by flow cytometry as Lin−CD11b−Ly6Chi CD115+, by 42.8% compared to treatment with EPO alone. In addition, CIB alone or in combination with EPO inhibited osteoclastogenesis in vitro. Our findings introduce CIB either as a stand-alone treatment, or in combination with EPO, as an appealing candidate for the treatment of the bone loss that accompanies EPO treatment. 相似文献
107.
Amlie Rousselire Laurence Delbos Cline Bressollette Maïlys Berthaume Batrice Charreau 《International journal of molecular sciences》2022,23(1)
HCMV drives complex and multiple cellular immune responses, which causes a persistent immune imprint in hosts. This study aimed to achieve both a quantitative determination of the frequency for various anti-HCMV immune cell subsets, including CD8 T, γδT, NK cells, and a qualitative analysis of their phenotype. To map the various anti-HCMV cellular responses, we used a combination of three HLApeptide tetramer complexes (HLA-EVMAPRTLIL, HLA-EVMAPRSLLL, and HLA-A2NLVPMVATV) and antibodies for 18 surface markers (CD3, CD4, CD8, CD16, CD19, CD45RA, CD56, CD57, CD158, NKG2A, NKG2C, CCR7, TCRγδ, TCRγδ2, CX3CR1, KLRG1, 2B4, and PD-1) in a 20-color spectral flow cytometry analysis. This immunostaining protocol was applied to PBMCs isolated from HCMV− and HCMV+ individuals. Our workflow allows the efficient determination of events featuring HCMV infection such as CD4/CD8 ratio, CD8 inflation and differentiation, HCMV peptide-specific HLA-EUL40 and HLA-A2pp65CD8 T cells, and expansion of γδT and NK subsets including δ2−γT and memory-like NKG2C+CD57+ NK cells. Each subset can be further characterized by the expression of 2B4, PD-1, KLRG1, CD45RA, CCR7, CD158, and NKG2A to achieve a fine-tuned mapping of HCMV immune responses. This assay should be useful for the analysis and monitoring of T-and NK cell responses to HCMV infection or vaccines. 相似文献
108.
Irina Sorokina Arcady R. Mushegian Eugene V. Koonin 《International journal of molecular sciences》2022,23(1)
The prevailing current view of protein folding is the thermodynamic hypothesis, under which the native folded conformation of a protein corresponds to the global minimum of Gibbs free energy G. We question this concept and show that the empirical evidence behind the thermodynamic hypothesis of folding is far from strong. Furthermore, physical theory-based approaches to the prediction of protein folds and their folding pathways so far have invariably failed except for some very small proteins, despite decades of intensive theory development and the enormous increase of computer power. The recent spectacular successes in protein structure prediction owe to evolutionary modeling of amino acid sequence substitutions enhanced by deep learning methods, but even these breakthroughs provide no information on the protein folding mechanisms and pathways. We discuss an alternative view of protein folding, under which the native state of most proteins does not occupy the global free energy minimum, but rather, a local minimum on a fluctuating free energy landscape. We further argue that ΔG of folding is likely to be positive for the majority of proteins, which therefore fold into their native conformations only through interactions with the energy-dependent molecular machinery of living cells, in particular, the translation system and chaperones. Accordingly, protein folding should be modeled as it occurs in vivo, that is, as a non-equilibrium, active, energy-dependent process. 相似文献
109.
柔性复合薄膜折叠损伤实验研究 总被引:3,自引:1,他引:2
对聚合物膜/预浸环氧碳纤维织物/聚合物膜这种三层薄膜材料(以下简称复合薄膜材料)的折叠损伤进行了试验研究.对未固化复合薄膜按一定折叠半径进行折叠,置于两平板间一定时间,然后展平加压加热固化并测试固化后复合薄膜材料的强度与刚度.结果表明,随着折叠半径的减少,材料的强度和等效拉伸模量下降.通过分析复合薄膜材料折叠损伤机理,确定了复合薄膜不发生损伤的最小折叠半径.另外,本研究还讨论了由于压缩屈曲导致的复合薄膜在拉伸中出现的分层破坏现象. 相似文献
110.
微带天线在各种内置天线通讯系统中有非常重要的应用.为满足便携式设备小型化的需要,该文介绍一种折叠式双层正方形微带贴片天线.此天线根据曲流原理,把常规的微带天线进行折叠.与常规微带天线相比,折叠式微带天线的尺寸减小了60%以上.折叠天线结构紧凑,便于加工制作.文中给出了天线的详细设计方案以及仿真结果.仿真结果证明该设计完全可以满足工程要求. 相似文献