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101.
Fan Zhang Dang Wu Gao-Lei Wang Shuang Hou Ping Ou-Yang Jin Huang Xiao-Yong Xu 《中国化学快报》2017,28(5):1044-1048
A series of novel 1,2,3-benzotriazin-4-one derivatives were designed,synthesized and their inhibitory activities against leulcotriene A_4 hydrolase aminopeptidase in vitro were evaluated.Many compounds showed moderate to good activities at the concentration of 10 μmol/L.Among them,compound Ⅳ-16 exhibited the highest inhibitory activity up to 80.6% with an IC_(50) of 1.30 ± 0.20 μmol/L The compound Ⅳ-16 was also tested the proliferation inhibitory activities in THP1 human AML cell line and its binding model with LTA_4H enzyme by molecular docking was studied.It indicated that 1,2,3-benzotriazin-4-one was a promising scaffold for further study.The relationship between structure and inhibitory activity was also preliminarily discussed. 相似文献
102.
Tianming Dai Weifan Jiang Zizheng Guo Zhenyu Wang Mingping Huang Guorui Zhong Chuxin Liang Xuzhe Pei Renke Dai 《Biomedical chromatography : BMC》2019,33(9)
Withaferin A (WA) is one of the major bioactive steroidal lactones with extensive pharmacological activities present in the plant Withania somnifera. The absolute oral bioavailability of WA remains unknown and human‐related in vitro data are not available. Therefore, in the present study, the absolute oral bioavailability of WA in male rats and the in vitro screening of absorption factors by Q‐trap and LC–MS/MS analysis were conducted to explore possible clinical properties of WA. The developed and validated analytical methods were successfully applied to the pharmacokinetic studies and in vitro measurement of WA. The oral bioavailability was determined to be 32.4 ± 4.8% based on intravenous (5 mg/kg) and oral (10 mg/kg) administrations of WA in male rats. The in vitro results showed that WA could be easily transported across Caco‐2 cells and WA did not show as a substrate for P‐glycoprotein. Moreover, the stability of WA was similar between male rat and human in simulated gastric fluid (stable), in intestinal microflora solution (slow decrease) and in liver microsomes (rapid depletion, with a half‐life of 5.6 min). As such, the first‐pass metabolism of WA was further verified by rat intestine‐liver in situ perfusion, revealing that WA rapidly decreased and 27.1% remained within 1 h, while the content of three major metabolites (M1, M4, M5) identified by Q‐trap increased. This perfusion result is consistent with the oral bioavailability results in vivo. The first‐pass metabolism of WA might be the main barrier in achieving good oral bioavailability in male rats and it is predicted to be similar in humans. This study may hold clinical significance. 相似文献
103.
In Situ Synthesis and Characterization of Poly(aryleneethynylene)‐Grafted Reduced Graphene Oxide
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Sai Sun Dr. Xiaodong Zhuang Prof. Dr. Bo Liu Luxing Wang Linfeng Gu Prof. Dr. Sannian Song Prof. Dr. Bin Zhang Prof. Dr. Yu Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(7):2247-2252
Using highly soluble bromo‐functionalized reduced graphene oxide (RGBr) as a key graphene template for surface‐directing Sonogashira–Hagihara polymerization, a novel soluble poly(arylene‐ethynylene)‐grafted reduced graphene oxide, hereafter abbreviated as PAE‐g‐RGO, was prepared in situ. The entirely different electron distribution of LUMO and HOMO of PAE‐g‐RGO suggested the existence of a charge‐transfer (CT) state (PAE.?–RGO.+). The negative ΔGCS value (?2.57 eV) indicates that the occurrence of the charge separation via 1RGO* in o‐DCB is exothermic and favorable. Upon irradiation with 365 nm light, the light‐induced electron paramagnetic resonance (LEPR) spectrum of PAE‐g‐RGO showed a decrease in the spin‐state density owing to photoinduced intramolecular electron transfer events in this system. A sandwich‐type Al/PAE‐g‐RGO/ITO device showed representative bistable electrical switching behavior. The nonvolatile memory performance was attributed to the CT‐induced conductance changes, which was supported by molecular computation results and conductive atomic force microscopy (C‐AFM) images. 相似文献
104.
通过在尿素前驱体中添加单宁酸, 原位缩聚形成碳自掺杂石墨相氮化碳(g-C3N4). 利用X射线光电子能谱(XPS)、 场发射扫描电子显微镜(FESEM)、 X射线衍射(XRD)仪和同步热分析(TG-DSC)等方法对碳自掺杂 g-C3N4的形貌、 物相结构和能带价态组分进行表征分析, 结合紫外-可见吸收光谱(UV-Vis)和原位光微量热-荧光光谱联用仪获得碳自掺杂g-C3N4降解罗丹明B的原位热/动力学信息和三维荧光光谱信息, 探讨了光催化降解罗丹明B的微观机制. 结果表明, 单宁酸浓度≤10 mg/mL时, 碳会取代七嗪单元结构的氮原子形成g-C3N4骨架碳自掺杂; 单宁酸浓度≥ 20 mg/mL时, 碳以无定形形式沉积负载在g-C3N4表面上形成无定形碳自掺杂. 骨架碳自掺杂g-C3N4形成的π电子有效缩短了禁带宽度, 减小了光生电子-空穴复合几率, 比无定形C掺杂g-C3N4显示出更优异的光催化性能, 催化主要活性物种为h+和·O . 碳自掺杂g-C3N4光催化降解过程可分为光响应吸热、 降解污染物放热平衡过程和稳定放热3个过程. 其中骨架碳自掺杂g-C3N4(C/N摩尔比为0.844)在光照1000 s内, 三维荧光光谱检测的RhB降解率锐减, 光照1000 s后, 其RhB降解率为87.6%, 分别是原始g-C3N4和无定形碳自掺杂g-C3N4的3.13倍和1.95倍. 光照1000 s后, 光微量热计显示以矿化和降解非荧光发色中间产物为主, 并保持以热变速率为(0.9799±0.5356) μJ/s稳定放热, 为拟零级反应过程, 是光催化反应的决速步骤. 相似文献
105.
Xiao-Ying Yu Jennifer Yao Edgar C. Buck Zihua Zhu 《Surface and interface analysis : SIA》2020,52(7):454-459
Trace analysis of nuclear materials in solid particles collected in the environment or particles in liquid slurry generated in nuclear material manufacturing processes can pinpoint elemental, organic, and isotopic signatures of nuclear fuel cycle activities and processes. Such information can support nuclear safeguards programs by increasing our ability to detect undeclared nuclear materials, routine activities for safeguarding at declared facilities, and illicit activities. However, trace radioactive material analysis in liquids and slurries is challenging using bulk approaches. For example, one drawback of sensitive analysis such as inductively coupled plasma mass spectrometry (ICP-MS) is that sample is consumed or destroyed as a result of the technical approach. We developed a vacuum compatible microfluidic interface to enable surface analysis of liquids and solid–liquid interactions using time-of-flight secondary ion mass spectrometry (ToF-SIMS). In this work, we illustrate the initial results from the analysis of liquid uranium oxide standard solutions using in situ liquid SIMS. Because the liquid SIMS analysis is almost nondestructive, the same sample can then be analyzed by other analytical techniques or saved for future reference. Consequently, multimodal analysis is possible. Our results demonstrate that in situ liquid SIMS can be used as a new approach to analyze radioactive materials in liquid and slurry forms of relevance to diverse applications. 相似文献
106.
S. Paszkiewicz A. Szymczyk Z. Špitalský M. Soccio J. Mosnáček T. A. Ezquerra Z. Rosłaniec 《Journal of Polymer Science.Polymer Physics》2012,50(23):1645-1652
Nanocomposites based on poly(ethylene terephthalate) (PET) and expanded graphite (EG) have been prepared by in situ polymerization. Morphology of the nanocomposites has been examined by electronic microscopy. The relationship between the preparation method, morphology, and electrical conductivity was studied. Electronic microscopy images reveal that the nanocomposites exhibit well dispersed graphene platelets. The incorporation of EG to the PET results in a sharp insulator‐to‐conductor transition with a percolation threshold (?c) as low as 0.05 wt %. An electrical conductivity of 10?3 S/cm was achieved for 0.4 wt % of EG. The low percolation threshold and relatively high electrical conductivity are attributed to the high aspect ratio, large surface area, and uniform dispersion of the EG sheets in PET matrix. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
107.
《中国化学》2018,36(2):157-161
The three‐dimensional nanoflower‐like β‐In2S3 composited with carbon nanotubes (CNTs) has been synthesized by a single mode microwave‐assisted hydrothermal technique. The In2S3 and CNTs nanocomposites (In2S3@CNTs) were investigated as the anode materials of lithium batteries (LIBs) and the electromagnetic wave absorption materials. For LIBs applications, the In2S3@CNTs nanocomposite exhibited excellent cycling stability with a high reversible charge capacity of 575 mA⋅h⋅g–1 after 300 cycles at 0.5 A⋅g–1. In addition, the In2S3@CNTs used as electromagnetic wave absorber displayed a maximum reflection loss of –42.75 dB at 11.96 GHz with a thickness of 1.55 mm. 相似文献
108.
Jared M. Schwartz Oluwadamilola Phillips Anthony Engler Alexandra Sutlief Jihyun Lee Paul A. Kohl 《Journal of polymer science. Part A, Polymer chemistry》2017,55(7):1166-1172
Low ceiling temperature, thermodynamically unstable polymers have been troublesome to synthesize and keep stable during storage. In this study, stable poly(phthalaldehyde) has been synthesized with BF3‐OEt2 catalyst. The role of BF3 in the polymerization is described. The interaction of BF3 with the monomer is described and used to maximize the yield and molecular weight of poly(phthalaldehyde). Various Lewis acids were used to investigate the effect of catalyst acidity on poly(phthalaldehyde) chain growth. In situ nuclear magnetic resonance was used to identify possible interactions formed between BF3 and phthalaldehyde monomer and polymer. The molecular weight of the polymer tracks with polymerization yield. The ambient temperature stability of poly(phthalaldehyde) was investigated and the storage life of the polymer has been improved. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 55, 1166–1172 相似文献
109.
The in situ ligand 2,3-pyrazinedicarboxylic acid (2,3-H2pzdc) mixed with 1,1′-(1,4-butanediyl)bis(benzimidazole) (bbbi) is used to form two coordination polymers ([Cd(2,3-pzdc)(bbbi)] (1) and [Cd2Cl3(2-pzc)(bbbi)2] (2)) under hydrothermal conditions. Complex 1 was obtained in the absence of in situ reaction and 2 was synthesized with 2,3-H2pzdc in situ generating 2-pyrazinecarboxylate (2-pzc?). The structural details reveal that 1 has a 3D framework with dia topology, and 2 is a 2D layer structure and develops a 3D supramolecular structure via strong π?π stacking interactions. The ligand effects were compared for the two frameworks. In addition, fluorescence properties and thermal stabilities of 1 and 2 in the solid were studied. 相似文献
110.