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941.
A Cu(II) coordination polymer (CP) (that is, [Cu2(OH)(H2O)2(cbca)·2H2O]n (1)) has been obtained with the reaction between Cu(II) salt and 4′-(1-carboxyethoxy)-[1,1′-biphenyl]-3,5-dicarboxylic acid (H3cbca), a semi-rigid tricarboxylic acid ligand under the hydrothermal reaction condition. Prevention activity of the new compound on hypotension after anesthesia surgery was evaluated and the related mechanism was researched at the same time. The noninvasive blood pressure monitor was firstly conducted to measure the blood pressure of the animal after compound treatment. Besides, the real time RT-PCR assay was also used to determine theα receptor relative expression on vascular endothelial cells after compound treatment. 相似文献
942.
《印度化学会志》2022,99(12):100799
A charge transfer hydrogen bonded complex was prepared and experimentally explored in an acetonitrile (ACN) medium between the proton acceptor (electron donor) 2, 3-Diamino-5-bromopyridine and the proton donor (electron acceptor) chloranilic acid. The stoichiometry of the charge transfer complex is 1:1. The Benesi-Hildebrand equation is used to calculate the molar absorptivity (εCT), association constant (KCT) and other spectroscopic physical characteristics. The solid compound was synthesized and studied using several spectroscopic methods. The presence of charge and proton transfers in the resultant complex was supported by 1H NMR, FT-IR and SEM-EDX investigations. The complex DNA binding ability was investigated using electron absorption spectroscopy, and the CT complex binding mechanism is intercalative. The intrinsic binding constant (Kb) value is 5.2 × 106M?1. The good binding affinity of the CT complex makes it potentially suitable for usage as a pharmaceutical in the future. Molecular docking calculations have been performed between CT complex and DNA (ID = 1BNA) to study the CT-DNA interaction theoretically. To corroborate the experimental findings, calculations based on DFT were carried out in the gas and PCM analysis where the existence of charge and hydrogen transfers. Finally, good agreement between experimental and theoretical computations was observed confirming that the basis set used is appropriate for the system under examination. 相似文献
943.
以α-Al2O3为支撑层, UiO-66为分离层, Co3O4为催化层, 构建了Co3O4/UiO-66@α-Al2O3陶瓷膜.对其形貌结构进行了表征, 并研究了其对挥发性有机物(VOCs)的分离催化性能. 结果表明, 该陶瓷膜对喷涂行业废气中苯与吡啶两种主要成分体现出良好的分离性, 透过侧的气体中吡啶与苯的摩尔浓度比值可由给料侧的1提高至17; 体系中引入臭氧后, 给料侧苯的浓度明显降低, 其去除率可达到89%. 透过侧的吡啶去除率仅为27%, 得到了较大程度的保留, 剩余的吡啶经收集后可进行单独的深度处理. Co3O4/UiO-66@α-Al2O3陶瓷膜在对喷涂行业废气中苯成分高效降解的同时, 能够有效解决喷涂行业废气处理过程中氮氧化物的排放问题, 有望成为喷涂行业废气预处理工艺的理想选择. 相似文献
944.
Jianfeng Zhang Dr. Marco Wenzel Johannes Steup Gerrit Schaper Dr. Felix Hennersdorf Prof. Dr. Hao Du Prof. Dr. Shili Zheng Prof. Dr. Leonard F. Lindoy Prof. Dr. Jan J. Weigand 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(1):e202103640
Effective receptors for the separation of Li+ from a mixture with other alkali metal ions under mild conditions remains an important challenge that could benefit from new approaches. In this study, it is demonstrated that the 4-phosphoryl pyrazolones, H L 2-H L 4, in the presence of the typical industrial organophosphorus co-ligands tributylphosphine oxide (TBPO), tributylphosphate (TBP) and trioctylphosphine oxide (TOPO), are able to selectively recognise and extract lithium ions from aqueous solution. Structural investigations in solution as well as in the solid state reveal the existence of a series of multinuclear Li+ complexes that include dimers (TBPO, TBP) as well as rarely observed trimers (TOPO) and represent the first clear evidence for the synergistic role of the co-ligands in the extraction process. Our findings are supported by detailed NMR, MS and extraction studies. Liquid-liquid extraction in the presence of TOPO revealed an unprecedented high Li+ extraction efficiency (78 %) for H L 4 compared to the use of the industrially employed acylpyrazolone H L 1 (15 %) and benzoyl-1,1,1-trifluoroacetone (52 %) extractants. In addition, a high selectivity for Li+ over Na+, K+ and Cs+ under mild conditions (pH ∼8.2) confirms that H L 2-H L 4 represent a new class of ligands that are very effective extractants for use in lithium separation. 相似文献
945.
Dr. Zhaowen Dong Dr. Andrzej Sienkiewicz Dr. Abdusalom A. Suleymanov Cesare Berton Dr. Farzaneh Fadaei-Tirani Dr. Rosario Scopelliti Prof. Kay Severin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(32):e202200893
Dichalcogenolenes are archetypal redox non-innocent ligands with numerous applications. Herein, a diselenolene ligand with fundamentally different electronic properties is described. A mesoionic diselenolene was prepared by selenation of a C2-protected imidazolium salt. This ligand is diamagnetic, which is in contrast to the paramagnetic nature of standard dichalcogenolene monoanions. The new ligand is also redox-active, as demonstrated by isolation of a stable diselenolene radical dianion. The unique electronic properties of the new ligand give rise to unusual coordination chemistry. Thus, preparation of a hexacoordinate aluminum tris(diselenolene) complex and a Lewis acidic aluminate complex with two ligand-centered unpaired electrons was achieved. 相似文献
946.
摘要:常温催化氧化是消除室内HCHO污染最可行的方法之一,其中以过渡金属氧化物为代表的催化剂因性能优异、成本低廉而备受广泛关注。采用柠檬酸络合法和水热法制备了一系列CuMnCeOx催化剂,研究考察制备方法及载体对催化剂氧化性能的影响,并利用XRD、SEM、BET、H2-TPR、XPS和IR等对催化剂进行微观表征与分析。研究发现,制备方法及载体类型对催化剂的表面结构形貌、氧化性能产生显著影响,其中采用柠檬酸络合法所制的CuMnCeOx-C催化剂性能最佳,48h的HCHO去除率达98.6%,完全满足GB50325-2001标准要求,其介孔结构,晶体粒径及所形成的铈基铜锰固溶体均利于形成大量氧空位及催化氧化反应,且展示出良好的抗水蒸气和稳定性能,其在常温催化氧化VOCs方面具有重要应用前景。 相似文献
947.
Tetrel bond, a weak noncovalent interaction between the σ-hole of a Group IV element (silicon in our case) and the cloud of an electronegative element (oxygen in our case) is the focus of this work. The percentage strengthening of tetrel bond has been investigated by optimizing 16 binary complexes of halogenated silane and water of general formula SiXnH4−n−H2O and 16 ternary complexes, of general formula NaX−SiXnH4−n−H2O, where X=F, Cl, Br and I and n=1, 2, 3 and 4 at various levels of theory defined within the formalism of density functional theory (DFT). With the addition of NaX, tetrel bond between Si and O in SiXnH4−n−H2O gets strengthened up to 49 %, owing to cooperativity effect exerted by hydrogen bonding between X and H in the ternary complex NaX−SiXnH4−n−H2O. In the series of complexes studied here, overall stabilization due to cooperativity lies between 10 kJ/mol to 170 kJ/mol. This large extent of reinforcement due to cooperativity has never been showcased before. The exceptional stabilization and reinforcement owe its genesis to the transformation of the ternary complex into a cluster orchestrated by the H-bonding in most of the cases and covalent bonding in few of the cases. 相似文献
948.
Thiacalixarene-supported Co32nanoclusters encapsulated in polyacrylonitrile nanofibers(Co32@PAN-NFs) by electrospinning have been utilized as precursors to fabricate N-doped CoO@Co9S8 carbon nanofibers(CoO@Co9S8@CNFs) for superior Li-ion storage. The S-rich Co32 clusters capped by organic sheets afforded the well dispersed cobalt oxide/sulfide nanoparticles embedded in carbon nanofiber composites by direct calcination. The N-doped CoO@Co9S8@CNFs nanocomposites have been utilized as anode materials for lithium ion battery with the reversible capabilities being of 1051.8, 967.6, 894.7, 782.7, 669.5 and 525.4 mA·h/g at 0.1, 0.2, 0.5, 1, 2 and 3 A/g, respectively. The CoO@Co9S8@CNFs also showed a relatively high stable capacity of 551.7 mA·h/g at the current density of 1 A/g after 200 cycles of rate experiments. The as-obtained N-doped CoO@Co9S8@CNFs nanocomposites exhibited superior reversible capacity, rate performance, Coulomb efficiency(74.5% vs. 63.9%) and cyclic stability comparing with the CoO@Co9S8@C derived from simple annealing of Co32 templates. 相似文献
949.
《Arabian Journal of Chemistry》2022,15(3):103640
Complexes of transition metals [Co(II), Cd(II) and Mo(0)] with a new enaminone (PA) 3-chloro-4-((4-methoxyphenyl)amino)pent-3-en-2-one were synthesized and afterwards characterized by 1H NMR, 13C NMR, FAB-MS, UV–Vis, ICP-OES, TGA and FTIR. The spectroscopic and conductance data suggested that the ligand (PA) is attached to the metal ions in bidentate, neutral form through the nitrogen atom of amino group and the oxygen of carbonyl group. Metal complexes displayed octahedral geometries. In vitro urease inhibition and cytotoxic activities of all the compounds were evaluated. Results revealed that Co(II) complex (PA-Co) was even more significant than the reference drug thiourea. Analysis of the cytotoxicity indicated that, the Co(II) complex has more cytotoxic effect than enaminone ligand and other complexes when assessed on the human cancer cell lines MCF-7.Molecular docking simulation was also performed to find out the putative binding mode within the target protein. 相似文献
950.
《Arabian Journal of Chemistry》2022,15(7):103922
Recently, the visible-light photoredox decarboxylative couplings of N-(acyloxy)phthalimides (NHPI esters) and its derivatives have become an efficient chemical transformation. Under visible light, the NHPI esters undergo a single-electron transfer (SET) process to afford the corresponding carbon or nitrogen radicals that participate in many chemical transformations. The photoredox decarboxylative couplings have been applied to achieve construction of an array of carbon–carbon and carbon–heteroatom bonds as well as the synthesis of carbocycles and heterocycles. This review categorises photocatalysts, discusses the application and catalysis mechanisms of NHPI esters, and details recent progress in this field. 相似文献