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61.
62.
Xuan Gao Yuhang Dai Chengyi Zhang Yixuan Zhang Wei Zong Wei Zhang Ruwei Chen Jiexin Zhu Xueying Hu Mingyue Wang Ruizhe Chen Zijuan Du Fei Guo Haobo Dong Yiyang Liu Hongzhen He Siyu Zhao Fangjia Zhao Jianwei Li Ivan P. Parkin Claire J. Carmalt Guanjie He 《Angewandte Chemie (International ed. in English)》2023,62(16):e202300608
The electrochemical effect of isotope (EEI) of water is introduced in the Zn-ion batteries (ZIBs) electrolyte to deal with the challenge of severe side reactions and massive gas production. Due to the low diffusion and strong coordination of ions in D2O, the possibility of side reactions is decreased, resulting in a broader electrochemically stable potential window, less pH change, and less zinc hydroxide sulfate (ZHS) generation during cycling. Moreover, we demonstrate that D2O eliminates the different ZHS phases generated by the change of bound water during cycling because of the consistently low local ion and molecule concentration, resulting in a stable interface between the electrode and electrolyte. The full cells with D2O-based electrolyte demonstrated more stable cycling performance which displayed ∼100 % reversible efficiencies after 1,000 cycles with a wide voltage window of 0.8–2.0 V and 3,000 cycles with a normal voltage window of 0.8–1.9 V at a current density of 2 A g−1. 相似文献
63.
Wei Zong Haiqi Gao Yue Ouyang Kaibin Chu Hele Guo Leiqian Zhang Wei Zhang Ruwei Chen Yuhang Dai Fei Guo Jiexin Zhu Zhenfang Zhang Chumei Ye Dr. Yue-E. Miao Prof. Johan Hofkens Dr. Feili Lai Prof. Tianxi Liu 《Angewandte Chemie (International ed. in English)》2023,62(27):e202218122
Competition from hydrogen/oxygen evolution reactions and low solubility of N2 in aqueous systems limited the selectivity and activity on nitrogen fixation reaction. Herein, we design an aerobic-hydrophobic Janus structure by introducing fluorinated modification on porous carbon nanofibers embedded with partially carbonized iron heterojunctions (Fe3C/Fe@PCNF-F). The simulations prove that the Janus structure can keep the internal Fe3C/Fe@PCNF-F away from water infiltration and endow a N2 molecular-concentrating effect, suppressing the competing reactions and overcoming the mass-transfer limitations to build a robust “quasi-solid–gas” state micro-domain around the catalyst surface. In this proof-of-concept system, the Fe3C/Fe@PCNF-F exhibits excellent electrocatalytic performance for nitrogen fixation (NH3 yield rate up to 29.2 μg h−1 mg−1cat. and Faraday efficiency (FE) up to 27.8 % in nitrogen reduction reaction; NO3− yield rate up to 15.7 μg h−1 mg−1cat. and FE up to 3.4 % in nitrogen oxidation reaction). 相似文献
64.
甲醛与乙醛,甲醚,硝基甲烷相互作用的从头算研究 总被引:1,自引:0,他引:1
用6-31G、全构型优化,研究了甲醛与乙醛、甲醚、硝基甲烷的相互作用。结果表明所有超分子稳定构型都包含2个C—H—O氢键的平面环状结构。H—O距离为0.228~0.264 nm,作用能为—19~—24 kJ/mol,与二聚水的作用能接近。稳定性主要取决于甲基上取代基Y吸电子能力以及环状结构中氢键张力。STO-3G不很适用于研究这类分子的相互作用。 相似文献
65.
66.
Chen?Zong Duoduo?Zhang Hua?Yang Shumei?Wang Ming?Chu Ping?LiEmail author 《Mikrochimica acta》2017,184(9):3197-3204
The authors describe an array for chemiluminescence (CL) based determination of cardiac troponin T (cTnT), an important cardiovascular disease marker. The tracing tag consists of silver nanoparticles (AgNPs) loaded with guanine-rich DNA sequences and detection antibody in a high numerical ratio. The loaded AgNPs were then reacted with hemin to form a hemin/G-quadruplex DNAzyme. A disposable immunosensor array was fabricated by immobilizing capture antibody on corresponding sensing sites on a glass chip. Once a sandwich immunocomplex is formed on the array, the tracing tag catalyzes the CL reaction of the luminol-p-iodophenol and H2O2 system to produce a CL signal, which is collected by a CCD camera. An intuitive CL image is obtained containing all of the spots on the array. Under optimal conditions, the method shows a wide linear range over 4 orders of magnitude (from 0.003 to 270 ng·L?1), a detection limit down to 84 fg·L?1, and a throughput as high as 44 tests·h?1. The results obtained with serum samples are in acceptable agreement with reference values. The AgNP-based tracing tag as well as the immunoassay method shows a promising potential for point-of-care testing for the early clinical diagnosis of cardiovascular disease. 相似文献
67.
Shuai Zong Lan Li Jinglei Li Farnaz Shaikh Liu Yang Ming Ye 《Applied biochemistry and biotechnology》2017,182(2):669-686
In the present study, an intracellular melanin, named LIM205, was separated from Lachnum YM205 mycelia and was purified on a Sephadex G-15 column. The molecular weight of LIM205 was determined as 522 Da, and its molecular formula was speculated as C28H14N2O7S. The possible chemical structure of LIM205 was determined according to the results of Fourier transform infrared (FT-IR), 1H NMR, 13C NMR, and pyrolysis/GC-MS analysis. With the aim to increase its water solubility, its carboxymethylated derivative, named CLIM205, was formed by the substitution of hydrogen atoms in LIM205 with one, two, and three carboxymethylate groups. FT-IR, UV, and ESI-MS analysis demonstrated that the carboxymethylate groups were conjugated onto LIM205. The lead detoxification activities of LIM205 and CLIM205 had also been investigated. In vivo test showed that both LIM205 and CLIM205 reduced the tissue lead concentration, enhanced lead excretion, and reversed lead-induced alterations in superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) concentrations in mice, with CLIM205 showed better efficacy. The study indicates that LIM205 and CLIM205 have significant lead detoxification effect which will contribute to solve related problems. 相似文献
68.
合成了孔道平行于短轴方向的W原位掺杂的介孔SBA-15分子筛(W-s-SBA-15), 以其为载体制备了Pt/W-s-SBA-15催化剂, 考察了催化剂中Pt、W负载量变化对甘油氢解制1,3-丙二醇(1,3-PDO)性能的影响. 采用多种手段对催化剂的形貌、活性组分Pt和W的存在状态、催化剂的酸性等性质进行了系统的表征. 催化剂评价结果表明, 随着Pt、W负载量的增加, 甘油的总转化率和液相转化率(CTL)提高, 而1,3-PDO选择性呈先升高后降低的火山型变化趋势. 在Pt负载量为4.0 wt%、W/Si物质的量比为1/480的4Pt/W-s-SBA-15(1/480)催化剂上, 在433 K、H2压力4.0 MPa、反应时间24 h的条件下, 甘油氢解制1,3-PDO的得率可达49.0%. 根据表征结果, 我们发现在Pt/W-s-SBA-15催化剂上的甘油转化率与Pt活性比表面积直接相关, 而小的Pt粒径、Pt与单分散WO4之间密切的协同作用, 则有助于提高1,3-PDO的选择性. 相似文献
69.
IntroductionOwingtoinhibitionofprostaglandinproduction,non-steroidsanti-inflammatorydrugs(NSAIDs)havebeenwidelyusedfortreatmentofbothacuteandchronicinflammatory'diseases'.Thesecompounds,however,exhibitserioussideeffectswithsignificantlylimittheiruseinalargeproportionofthepatients=.Arachidonicacidisaconvertedtoprostaglandin(PGs)byatleasttwoisoformsoftheenzymecyclooxygenase;.Theconstitutiveformoftheenzyme(COX-l)isresponsibleforthenormalproductionofPGs.Aninductiveformofcyclooxygenase(COX-… 相似文献
70.
The synthesis of the first derivatives of bis(pyrrolo[3,4-d])tetrathiafulvalene has been studied in detail. Starting from the readily available 2,5-dimethylpyrrole (11) and N-phenyl-2,5-dimethylpyrrole, bis(2,5-dimethylpyrrolo[3,4-d])tetrathiafulvalene (8) and the N,N'-disubstituted derivatives 6, 7, 9, and 10 were prepared in good yields by practical procedures. In contrast to the other types of aromatic annelated tetrathiafulvalenes (TTFs), which have appreciably higher oxidation potentials than TTF, the redox behavior of the pyrrolo tetrathiafulvalenes (TTFs) is very close to that of TTF itself. The potential of pyrrolotetrathiafulvalenes as a new series of organic metal building blocks is shown by the two-probe conductivities of the tetracyanoquinodimethane (TCNQ) complexes of the N-phenyl compound 7 and the N-methyl compound 9, which give higher values than TTF-TCNQ under similar conditions. 相似文献