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171.
Yuxin An Qian Li Jiejun Chen Xiaokang Gao Hongwei Chen Chaoni Xiao Liujiao Bian Jianbin Zheng Xinfeng Zhao Xiaohui Zheng 《Biomedical chromatography : BMC》2014,28(12):1881-1886
A new mathematical model and frontal analysis were used to characterize the binding behavior of caffeic acid to human serum albumin (HSA) based on high‐performance affinity chromatography. The experiments were carried out by injecting various mole amounts of the drug onto an immobilized HSA column. They indicated that caffeic acid has only one type of binding site to HSA on which the association constant was 2.75 × 104/m . The number of the binding site involving the interaction between caffeic acid and HSA was 69 nm . The data obtained by the frontal analysis appeared to present the same results for both the association constant and the number of binding sites. This new model based on the relationship between the mole amounts of injection and capacity factors assists understanding of drug–protein interaction. The proposed model also has the advantages of ligand saving and rapid operation. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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173.
The numerical investigation of wave propagation in the asymptotic domain of Kerr spacetime has only recently been possible thanks to the construction of suitable hyperboloidal coordinates. The asymptotics revealed an apparent puzzle in the decay rates of scalar fields: the late-time rates seemed to depend on whether finite distance observers are in the strong field domain or far away from the rotating black hole, an apparent phenomenon dubbed ‘splitting.’ We discuss far-field ‘splitting’ in the full field and near-horizon ‘splitting’ in certain projected modes using horizon-penetrating, hyperboloidal coordinates. For either case we propose an explanation to the cause of the ‘splitting’ behavior, and we determine uniquely decay rates that previous studies found to be ambiguous or immeasurable. The far-field ‘splitting’ is explained by competition between projected modes. The near-horizon ‘splitting’ is due to excitation of lower multipole modes that back excite the multipole mode for which ‘splitting’ is observed. In both cases ‘splitting’ is an intermediate effect, such that asymptotically in time strong field rates are valid at all finite distances. At any finite time, however, there are three domains with different decay rates whose boundaries move outwards during evolution. We then propose a formula for the decay rate of tails that takes into account the inter-mode excitation effect that we study. 相似文献
174.
Jing Wenguang Zhao Xiaoliang Liu An Wei Feng Ma Shuangcheng 《Chemistry of Natural Compounds》2022,58(3):501-505
Chemistry of Natural Compounds - Two new nitrogenous compounds identified as (2S)-2-sinapoyl-4-pentenenitrile (1) and brassicalkaloid A (2) have been isolated from the seed of Brassica napus L.... 相似文献
175.
Dr. Ying Wang Dr. Wenming Sun Xiaofei Ling Xiangkai Shi Dr. Lanlan Li Prof. Yida Deng Dr. Cuihua An Dr. Xiaopeng Han 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(18):4097-4103
The development of high-efficiency, low-cost, and earth-abundant electrocatalysts for overall water splitting remains a challenge. In this work, Ni-modified MoS2 hybrid catalysts are grown on carbon cloth (Ni-Mo-S@CC) through a one-step hydrothermal treatment. The optimized Ni-Mo-S@CC catalyst shows excellent hydrogen evolution reaction (HER) activity with a low overpotential of 168 mV at a current density of 10 mA cm−2 in 1.0 m KOH, which is lower than those of Ni-Mo-S@CC (1:1), Ni-Mo-S@CC (3:1), and pure MoS2. Significantly, the Ni-Mo-S@CC hybrid catalyst also displays outstanding oxygen evolution reaction (OER) activity with a low overpotential of 320 mV at a current density of 10 mA cm−2, and remarkable long-term stability for 30 h at a constant current density of 10 mA cm−2. Experimental results and theoretical analysis based on density functional theory demonstrate that the excellent electrocatalytic performance can be attributed mainly to the remarkable conductivity, abundant active sites, and synergistic effect of the Ni-doped MoS2. This work sheds light on a unique strategy for the design of high-performance and stable electrocatalysts for water-splitting electrolyzers. 相似文献
176.
Belyaev B. A. Tyurnev V. V. Voloshin A. S. Leksikov An. A. Galeev R. G. Shabanov V. F. 《Doklady Physics》2020,65(9):343-348
Doklady Physics - The design of a multilayer bandpass filter has been investigated, in which each of the half-wavelength resonators consists of two dielectric layers with outer strip conductor... 相似文献
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178.
An Unprecedented Two‐Fold Nested Super‐Polyrotaxane: Sulfate‐Directed Hierarchical Polythreading Assembly of Uranyl Polyrotaxane Moieties
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Dr. Lei Mei Dr. Qun‐yan Wu Dr. Li‐yong Yuan Dr. Lin Wang Shu‐wen An Zhen‐ni Xie Dr. Kong‐qiu Hu Prof. Zhi‐fang Chai Prof. Peter C. Burns Prof. Wei‐qun Shi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(32):11329-11338
The hierarchical assembly of well‐organized submoieties could lead to more complicated superstructures with intriguing properties. We describe herein an unprecedented polyrotaxane polythreading framework containing a two‐fold nested super‐polyrotaxane substructure, which was synthesized through a uranyl‐directed hierarchical polythreading assembly of one‐dimensional polyrotaxane chains and two‐dimensional polyrotaxane networks. This special assembly mode actually affords a new way of supramolecular chemistry instead of covalently linked bulky stoppers to construct stable interlocked rotaxane moieties. An investigation of the synthesis condition shows that sulfate can assume a vital role in mediating the formation of different uranyl species, especially the unique trinuclear uranyl moiety [(UO2)3O(OH)2]2+, involving a notable bent [O=U=O] bond with a bond angle of 172.0(9)°. Detailed analysis of the coordination features, the thermal stability as well as a fluorescence, and electrochemical characterization demonstrate that the uniqueness of this super‐polyrotaxane structure is mainly closely related to the trinuclear uranyl moiety, which is confirmed by quantum chemical calculations. 相似文献
179.
Both residual Cesàro alpha-integrability (RCI( α)) and strongly residual Cesàro alpha-integrability (SRCI(α)) are two special kinds of extensions to uniform integrability, and both asymp-totically almost negative association (AANA) and asymptotically quadrant sub-independence (AQSI) are two special kinds of dependence structures. By relating the RCI(α) property as well as the SRCI(α) property with dependence condition AANA or AQSI, we formulate some tail-integrability conditions under which for appropriate α the RCI(α) property yields L1-convergence results and the SRCI(α) property yields strong laws of large numbers, which is the continuation of the corresponding literature. 相似文献
180.
Jian-Ming Zhang Shang-Ru Zhai Bin Zhai Qing-Da An Ge Tian 《Journal of Sol-Gel Science and Technology》2012,64(2):347-357
Multifunctional nanomaterials with task-specific physicochemical properties, especially core?Cshell nanostructures with Fe3O4 core and NH2-functional shells (Fe3O4@SiO2?CNH2), have been extensively investigated as high-performance adsorbents, catalysts and catalyst supports; and in most cases the controllable sol?Cgel technique is the choice for fabrication of this kind of widely applied materials. Herein, we demonstrated that mono-dispersed and spherical Fe3O4@SiO2?CNH2 nanomaterials with magnetic response core, NH2-functional shell structure can be facilely prepared by co-condensation of TEOS with APTMS using a versatile sol?Cgel process. It was shown that the proper usage of APTMS and appropriate pre-hydrolysis time of TEOS were crucial and key steps for formation of highly uniform and desirable amino loading Fe3O4@SiO2?CNH2 materials. The TEOS pre-hydrolysis and the critical time (around 90?min) before the addition of APTMS prove to be vital for uniform structure evolution, while the appropriate concentration of APTMS (~2.28?mmol?L?1 in our system) leads to well-dispersed materials with relatively high loading of amino functionality. The as-prepared Fe3O4@SiO2?CNH2 magnetic nanoparticles prepared under optimum conditions possessing superparamagnetic behavior, uniform core?Cshell structure (~200?nm in diameter), relatively large BET surface area (~138?m2/g) and high incorporation of amino-functionality (~2.90?wt?%). 相似文献