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101.
We propose a facile room‐temperature synthesis of a metal–organic framework (MOF) with a bimodal mesoporous structure (3.9 and 17‐28 nm) in an ionic liquid (IL)/ethylene glycol (EG) mixture. The X‐ray diffraction analysis reveals that MOF formation can be efficiently promoted by the presence of the EG/IL interface at room temperature. The MOFs with mesoporous networks are characterized by SEM and TEM. The formation mechanism of the mesoporous MOF in EG/IL mixture is investigated. It is proposed that the EG nanodroplets in the IL work as templates for the formation of the large mesopores. The as‐synthesized mesoporous metal–organic framework is an effective and reusable heterogeneous catalyst to catalyze the aerobic oxidation of benzylic alcohols.  相似文献   
102.
103.
The term systems pharmacology describes a field of study that uses computational and experimental approaches to broaden the view of drug actions rooted in molecular interactions and advance the process of drug discovery. The aim of this work is to stick out the role that the systems pharmacology plays across the multi-target drug discovery from natural products for cardiovascular diseases (CVDs). Firstly, based on network pharmacology methods, we reconstructed the drug–target and target–target networks to determine the putative protein target set of multi-target drugs for CVDs treatment. Secondly, we reintegrated a compound dataset of natural products and then obtained a multi-target compounds subset by virtual-screening process. Thirdly, a drug-likeness evaluation was applied to find the ADME-favorable compounds in this subset. Finally, we conducted in vitro experiments to evaluate the reliability of the selected chemicals and targets. We found that four of the five randomly selected natural molecules can effectively act on the target set for CVDs, indicating the reasonability of our systems-based method. This strategy may serve as a new model for multi-target drug discovery of complex diseases.  相似文献   
104.
Novel bismuth oxide (Bi2O3) nanoporous films were fabricated through anodization of bismuth foil in electrolytes containing glycol, ammonium sulfate ((NH4)2SO4) and deionized (DI) water. Scanning electron microscopy analysis indicated that morphology of the anodized bismuth foil changed markedly along with the changing of oxidation time, water content, electrolyte concentration, temperature, and applied voltages. The optimized morphology was obtained when bismuth was anodized at 20 V, 40 °C for 40 min in glycol solution containing 0.3 wt% (NH4)2SO4 and 5 wt% DI water. The composition and crystal structure of the samples formed in the optimized conditions were characterized by energy-dispersive spectroscopy and X-ray diffraction. Results showed that the as-prepared nanoporous structures were amorphous. β-Bi2O3 was obtained when the samples were annealed at 200 °C. The photocurrent response experiments demonstrated that the Bi2O3 nanoporous film can generate photocurrent as large as 2.893 and 6.980 μA/cm2 under 0 and 0.5 V bias voltage versus saturated calomel electrode, respectively.  相似文献   
105.
研究了土壤提取液中游离氧化铁含量的FIA-ICP-AES测定法。考察了采术量以及提取剂(盐酸羟胺和草酯)的浓度对的影响。试验表明:如果选择50μL采样环进样,并将盐酸羟爱和草酸的浓度控制在10mg.mL^-1以下,则进样顺畅,不出现喷雾嘴堵塞的现象,分析线的背景干扰也得到有效抑制。此法的回收率为97.6%~100%,RSD≤3.5%。  相似文献   
106.
对苯醌荷移分光光度法测定头孢唑啉钠含量   总被引:4,自引:0,他引:4  
在pH 9.0硼砂缓冲溶液中 ,头孢唑啉钠与对苯醌发生荷移反应 ,形成稳定的 1∶2配合物 ,其最大吸收波长为 6 19.4nm ;表观摩尔吸光系数为 1.0 2× 10 4 L/ (mol·cm) ;线性范围为 0 .9~ 48μg/mL ;线性方程A =0 .0 2 0 33C +0 .0 1142 ;该法的相对标准偏差 0 .5 %~ 5 .3 % .应用该法测定注射用头孢唑啉钠含量与中国药典方法分析结果一致  相似文献   
107.
Graphene/hierarchy structure manganese dioxide (GN/MnO2) composites were synthesized using a simple microwave-hydrothermal method. The properties of the prepared composites were analyzed using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) measurements. The electrochemical performances of the composites were analyzed using cyclic voltammetry, electrochemical impedance spectrometry (EIS), and chronopotentiometry. The results showed that GN/MnO2 (10 wt% graphene) displayed a specific capacitance of 244 F/g at a current density of 100 mA/g. An excellent cyclic stability was obtained with a capacity retention of approximately 94.3% after 500 cycles in a 1 mol/L Li2SO4 solution. The improved electrochemical performance is attributed to the hierarchy structure of the manganese dioxide, which can enlarge the interface between the active materials and the electrolyte. The prepa- ration route provides a new approach for hierarchy structure graphene composites; this work could be readily extended to the preparation of other graphene-based composites with different structures for use in energy storage devices.  相似文献   
108.
杯芳烃固定液分子识别的热力学性质   总被引:3,自引:0,他引:3  
用毛细管气相色谱法测得了5组芳香族位置异构体在杯芳冠醚聚硅氧烷(C[4]C5_PSO),二乙氧基杯芳烃聚硅氧烷(C[4]E_PSO)和二丁氧基杯芳烃聚硅氧烷(M_C[4]B_PSO)3种杯芳烃固定液上的热力学参数ΔH、ΔS、ΔG,然后用热力学及超热力学的方法探讨了杯芳烃对异构体的分子识别特性和保留机理。  相似文献   
109.
The phase behavior, density, and constant-volume molar heat capacity (Cv,m) of ethane + n-pentane binary mixtures have been measured in the supercritical region and subcritical region at T=309.45 K. In addition, the isothermal compressibility (κT) has been calculated using the density data determined. For a mixed fluid with a composition close to the critical composition, Cv,m and κT increase sharply as the pressure approaches the critical point (CP), the dew point (DP), or the bubble point (BP). However, Cv,m is not sensitive to pressure in the entire pressure range if the composition of the mixed fluid is far from the critical composition. To tune the properties of the binary mixtures effectively by pressure, both the composition and the pressure should be close to the critical point of the mixture. The intermolecular interactions in the mixture are also discussed on the basis of the experimental results.  相似文献   
110.
Synthesis of single-crystal gold nanosheets of large size in ionic liquids   总被引:6,自引:0,他引:6  
Large-size single-crystal gold nanosheets have been successfully prepared by microwave heating of HAuCl(4) in ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate, without any additional template agent. Transmission electron microscopy (TEM), electron diffraction (ED), scanning electron microscopy (SEM), and X-ray powder diffraction (XRD) were used to characterize the resultant gold nanosheets. It was demonstrated that the ionic liquid could act as template agent for the formation of gold nanosheets. The present synthesis route is very simple and fast. It can be expected that the method can be extended to the fabrication of other metal nanosheets in ionic liquids.  相似文献   
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