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961.
气液平衡是理论教学和实际生产中的重要内容。本文从微观本质讨论理论教学中的拉乌尔定律和亨利定律以及实际生产中的恒沸溶液之间的关系和区别。溶剂-溶剂、溶剂-溶质和溶质-溶质之间相互作用的不同导致两个定律仅适用于稀溶液。这些相互作用通过物质的量分数调节溶剂和溶质的表观蒸气压,当二者的表观蒸气压相等时,则产生了恒沸溶液。 相似文献
962.
Ruirui Li Pengfei Gu Xiangyu Fan Junyu Shen Yulian Wu Lixuan Huang Qiang Li 《Applied biochemistry and biotechnology》2018,185(1):233-247
Single-chain variable fragment (scFv) antibodies as therapeutic agents have the potential to reduce the production cost and immunogenicity relative to monoclonal antibodies, but their monovalency and lack of a fragment crystallizable region can lead to reduced function. Multimerization is one strategy for recovering the function; however, their application is limited by the production of multimeric proteins. In our previous study, an anti-lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) scFv showed potential use in diagnosis and therapy of atherosclerotic diseases, but is limited by its inherent low antigen-binding activity. In this study, to improve the efficacy of the anti-LOX-1 scFv, we constructed the anti-LOX-1 scFv multimers by modifying the linker length between the variable domains of the scFv or by fusing the scFv with self-merization domains and expressed these scFv multimers in Brevibacillus choshinensis hosts. After optimization, all of the scFv multimers obtained efficient secretion expression. Compared with the scFv monomer, the multimers that are successfully fractionated displayed increased neutralization activity and showed elevated antigen-binding avidity, especially the tetramer, which improved the antigen avidity by two orders of magnitude. Moreover, the scFv dimer and the tetramer both displayed better stability and longer half-life in serum, which can be attractive candidates for the next-generation anti-LOX-1 therapeutic antibody. 相似文献
963.
TEMPO/CuI was found to be an effective catalyst for the cross-coupling of indoles with benzylic amines affording the corresponding bis(indolyl)phenylmethanes under air atmosphere at room temperature in good to excellent yields. The efficiency, easy workup, simplicity, and chemoselectivity of this protocol provide a green and low-cost procedure for the synthesis of these compounds. 相似文献
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965.
A supramolecular complex of Cd(Ⅱ) with 1D water tapes as pillars[Cd2(dpa)2(phen)2- (H2O)2]·6H2O 1 (H2dpa = diphenic acid, phen = phenanthroline), has been synthesized and characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction analysis. The crystal is of triclinic, space group Pī with a = 9.7029(4), b = 11.9601(5), c = 12.1788(4) A, a = 71.6990(10), β = 71.8740(10), γ = 74.4680(10)°, V = 1252.39(8) A3 C52H48Cd2N4O16, Mr = 1209.76, Z = 1, Dc = 1.604 g/cm3,μ = 0.925 mm-1, F(000) = 612, R = 0.0679 and wR = 0.2514 for 3870 observed reflections (Ⅰ > 2σ(Ⅰ)). Two intramolecular Cd(Ⅱ) centers of this complex are encircled by two dpa2- ligands forming an 18-membered ring, which is further assembled into a pillared three-dimensional (3D) supramolecular architecture through the synergetic effect of intermolecular face-to-face π…π stacking and weak O-H…O hydrogen-bonding interactions. Moreover, this complex exhibits photoluminescence with the main emission bands located at about 456 nm upon excitation at 355 nm in the solid state at room temperature. 相似文献
966.
Keming Song Xiang Wang Zhengkun Xie Zhiwei Zhao Zhe Fang Zhengfeng Zhang Jun Luo Pengfei Yan Zhangquan Peng Weihua Chen 《Angewandte Chemie (International ed. in English)》2023,62(10):e202216450
Solid-electrolyte interphase (SEI) seriously affects battery's cycling life, especially for high-capacity anode due to excessive electrolyte decomposition from particle fracture. Herein, we report an ultrathin SEI (3–4 nm) induced by Cu+-tailored double electrical layer (EDL) to suppress electrolyte consumption and enhance cycling stability of CuS anode in sodium-ion batteries. Unique EDL with SO3CF3-Cu complex absorbing on CuS in NaSO3CF3/diglyme electrolyte is demonstrated by in situ surface-enhanced Raman, Cyro-TEM and theoretical calculation, in which SO3CF3-Cu could be reduced to CuF2-rich SEI. Dispersed CuF2 and F-containing compound can provide good interfacial contact for formation of ultrathin and stable SEI film to minimize electrolyte consumption and reduce activation energy of Na+ transport. As a result, the modified CuS delivers high capacity of 402.8 mAh g−1 after 7000 cycles without capacity decay. The insights of SEI construction pave a way for high-stability electrode. 相似文献
967.
968.
969.
970.
Population of Unstable Nuclides and Nuclear Temperature Extraction in 46.7MeV/u 12C Induced Reaction 下载免费PDF全文
XI Hong-Fei ZHAN Wen-Long ZHU Yong-Tai GUO Zhong-Yan HU Xiao-Qing LIU Guan-Hua ZHOU Jian-Qun YIN Shu-Zhi ZHAO You-Xong WEI Zhi-Yong FAN En-Jie 《中国物理C(英文版)》1993,17(4):294-299
The experiment results of unstable nucliaes decay by using the light charged particle correlation function obtained in 12C 46.7MeV/u+58Ni experiment are reported.Under the assumption of statistical equilibrium,the nuclear temperatures are extracted,and the influence of the reaction mechanism on the nuclear temperature are also investigated. 相似文献