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981.
从理论和实验上研究了红绿荧光强度反转现象。实验测量发现Er(0.5)Yb(9.5)∶FOV纳米相氟氧化物玻璃陶瓷存在强的红绿荧光强度反转现象,实验测量得到其红绿荧光强度反转动态范围为877,同时计算了Er(0.5)Yb(9.5)∶FOV的所有基础光谱参量,建立了对系统所有稀土离子能级的动力学过程进行数值模拟计算的理论基础。  相似文献   
982.
A sensitive, selective, and simple liquid chromatography-tandem mass spectrometry method has been developed for the simultaneous separation and determination of isosorbide dinitrate and its active metabolite, isosorbide 5-mononitrate, in human plasma. Topiramate was used as the internal standard. Sample preparation consisted of a simple one-step liquid–liquid extraction with ethylacetate without pH adjustment. The method was fully validated with respect to linearity, sensitivity, specificity, recovery, accuracy, and precision. Isosorbide dinitrate and isosorbide 5-mononitrate were stable in standard solution and in plasma samples under storage and processing conditions. The assay was successfully applied to the pharmacokinetic study of isosorbide dinitrate and isosorbide 5-mononitrate in human plasma.  相似文献   
983.
以全苄基保护的糖酸内酯为原料,通过正丁基锂/二碘甲烷生成的碘甲基锂试剂对底物羰基加成增长碳链,再在碱性环境中水解合成了5个稀有酮糖中间体,其结构经NMR确认。  相似文献   
984.
Carbon black (CB) without micropores was functionalized by mixed acid and used to explore the surface chemistry effect on the production of hydrogen peroxide (H2O2). The CB materials were characterized by N2 adsorption‐desorption, XRD, SEM, FTIR, and TPD. The results of different characterization methods indicated that both the textural features and the surface chemical properties of CB were significantly modified by the acidic treatment. The catalytic performance of the modified CBs for hydroxylamine (NH2OH) oxidation increased with increasing the surface oxygen‐containing species. The yield of H2O2 approached 30% with the corresponding concentration of 73.9 mmol·L?1 (w=0.25%) over the most promising CB catalyst, which was much superior to the results obtained on supported noble metals. Correlations between catalytic activity and concentration of different surface functional groups on the CB samples confirmed that the quinonoid species might be the active species.  相似文献   
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988.
Salvianolic acid B is one of the effective components from the Chinese traditional drug Salvia miltiorrhiza (Danshen), which is widely used as a usual clinic drug for atherosclerosis-related disorder patients in China. But the targeting protein of salvianolic acid B is still not known. The possible targeting proteins of salvianolic acid B were explored by high throughput screening in this paper. Attached to the magnetic nanoparticles, salvianolic acid B was used for screening the high-affinity protein from the displaying cDNA peptide library phage. After biopanning, the selected protein or peptide sequences were used to explore the whole proteins containing the selected sequences in the National Center for Biotechnology Information website using blast. One of the selected phages was carried out by affinity analysis with salvianolic acid B using capillary electrophoresis (CE). The CE results indicated that the protein or peptide on the surface of the selected phages could bind the drug salvianolic acid B. The results are helpful to preliminarily explain the pharmacology of salvianolic acid B.  相似文献   
989.
Anew layered Cu-formate hydrate of Cu(HCOO)2·1/3H2O is unique in its water content and the strongly waved (4,4) Cu-formate layers held by interlayer weak axial Cu-Oformate bonds and O-Hwater···Oformate hydrogen bonds. The crystal is in orthorhombic space group Pbcn, with cell parameters at 80 K:a=7.9777(2) Å, b=7.3656(2) Å, c=21.0317(5) Å(1 Å=10−1 nm), and V=1235.83(5) Å3. The Cu2+ ions are in the environments of a square pyramid and elongated octahedron, in a ratio of 1/2 within the structure. In the layer, Cu2+ ions are connected by anti-anti formates via short basal Cu-O bonds. The structure remains unchanged until the dehydration that produces the layered anhydrous β-Cu(HCOO)2, and the possible transformation mechanism, supported by diffraction evidence, is the reorganization of the Cu-Oformate bonds across the parent layers after dehydration. The two phases exhibit anisotropic thermal expansion behaviors closely relevant to the transverse thermal vibrations of the constituents. Cu(HCOO)2·1/3H2O is a 2-dimensional Heisenberg antiferromagnet, and exhibits a global spin-canted antiferromagnetism with the Néel temperature of 32.1 K. This is not only higher than that of the magnetically denser β-Cu(HCOO)2, but also the highest among the copper formate frameworks.  相似文献   
990.
Shen  Honglong  Yang  Xiaoqiang  Song  Juanjuan  Gao  Haiwen  Wu  Zongdeng  Yu  Jia  Lei  Wu  Yang  Jiazhi  He  Guangyu  Hao  Qingli 《Journal of Solid State Electrochemistry》2022,26(2):353-363
Journal of Solid State Electrochemistry - Long-cycle stability and high-energy density are big challenges for developing high-performance hybrid supercapacitor (HSC) electrode materials. In this...  相似文献   
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