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91.
Dr. Ligang Wang Dr. Hui Su Zhuang Zhang Junjie Xin Hai Liu Dr. Xiaoge Wang Dr. Chenyu Yang Xiao Liang Dr. Shunwu Wang Dr. Huan Liu Yanfei Yin Taiyan Zhang Prof. Yang Tian Dr. Yaping Li Prof. Qinghua Liu Prof. Xiaoming Sun Prof. Junliang Sun Prof. Dingsheng Wang Prof. Yadong Li 《Angewandte Chemie (International ed. in English)》2023,62(49):e202314185
Developing cost-effective and sustainable acidic water oxidation catalysts requires significant advances in material design and in-depth mechanism understanding for proton exchange membrane water electrolysis. Herein, we developed a single atom regulatory strategy to construct Co−Co dinuclear active sites (DASs) catalysts that atomically dispersed zirconium doped Co9S8/Co3O4 heterostructure. The X-ray absorption fine structure elucidated the incorporation of Zr greatly facilitated the generation of Co−Co DASs layer with stretching of cobalt oxygen bond and S−Co−O heterogeneous grain boundaries interfaces, engineering attractive activity of significantly reduced overpotential of 75 mV at 10 mA cm−2, a breakthrough of 500 mA cm−2 high current density, and water splitting stability of 500 hours in acid, making it one of the best-performing acid-stable OER non-noble metal materials. The optimized catalyst with interatomic Co−Co distance (ca. 2.80 Å) followed oxo-oxo coupling mechanism that involved obvious oxygen bridges on dinuclear Co sites (1,090 cm−1), confirmed by in situ SR-FTIR, XAFS and theoretical simulations. Furthermore, a major breakthrough of 120,000 mA g−1 high mass current density using the first reported noble metal-free cobalt anode catalyst of Co−Co DASs/ZCC in PEM-WE at 2.14 V was recorded. 相似文献
92.
Meiyun Su Lina Guo Peiyu Mao Meng Xiao Prof. Dr. Wenjie Liu Prof. Dr. Shaohua Wang 《European journal of organic chemistry》2023,26(29):e202300268
The catalyst-free electrochemical halogenation and trifluoromethylation of 4H-pyrido[1,2-a]pyrimidin-4-ones was realized under external-oxidant-free conditions. This strategy provides an easy and green access to functionalized new 4H-pyrido[1,2-a]pyrimidin-4-one derivatives with broad scope, good functional group tolerance and high regioselectivity. 相似文献
93.
Lei Lv Hang Su Shanbin Chen Jinxing He Yuhong Yang Yuan Liu Hanzhu Xing 《Journal of separation science》2023,46(11):2200910
3-Chloro-1,2-propanediol is a common food contaminant, but reports on its determination in biological tissues are lacking. In the present study, a method was developed to detect 3-chloro-1,2-propanediol contents in rat tissues by quick-easy-cheap-effective-rugged-and-safe extraction and gas chromatography-mass spectrometry analysis. Biological samples were extracted with ethyl acetate and purified with adsorbents. The optimized adsorbent for each sample was selected from 4–5 combinations of N-propylethylenediamine, octadecylsilane, graphitized carbon black, strong anion exchange, and florisil. Extracted 3-chloro-1,2-propanediol was derivatized with heptafluorobutyric anhydride and subjected to gas chromatography-mass spectrometry. This method had good linearity (correlation coefficients >0.99) in the range of 2–2000 ng/g for blood, kidney, liver, testis, and brain samples. The limits of detection were under 0.8 ng/g; the limits of quantification were 2 ng/g; the recovery rates were 85%–102%; and the matrix effects were 1.98%–7.67%. This method also had good precision. The dynamic changes in 3-chloro-1,2-propanediol in rats gavaged with 20 mg/kg b.w. for 24 h were detected using this method. The 3-chloro-1,2-propanediol content in each tissue sharply increased to a peak, rapidly decreased within 2 h, and stabilized at 12 h. 3-Chloro-1,2-propanediol persisted in the kidney, testis, and liver 24 h after gavage. 相似文献
94.
A novel strategy for the construction of many-electron symmetry-adapted wave function is proposed for ab initio valence bond (VB) calculations and is implemented for valence bond self-consistent filed (VBSCF) and breathing orbital valence bond (BOVB) methods with various orbital optimization algorithms. Symmetry-adapted VB functions are constructed by the projection operator of symmetry group. The many-electron symmetry-adapted wave function is expressed in terms of symmetry-adapted VB functions, and thus the VB calculations can be performed with the molecular symmetry restriction. Test results show that molecular symmetry reduces the computational cost of both the iteration numbers and CPU time. Furthermore, excited states with specific symmetry can be conveniently obtained in VB calculations by using symmetry-adapted VB functions. 相似文献
95.
Mengdi Lv Yue Zheng Jian Wu Zhengqi Shen Binglian Guo Guojing Hu Yuanlei Huang Jingyue Zhao Prof. Yong Qian Prof. Zhi Su Prof. Chao Wu Prof. Xuling Xue Prof. Hong-Ke Liu Prof. Zong-Wan Mao 《Angewandte Chemie (International ed. in English)》2023,62(48):e202312897
Ferroptosis is a form of programmed cell death driven by iron-dependent lipid peroxidation (LPO) with the potential for antitumor immunity activation. In this study, a nonferrous cyclopentadienyl metal-based ferroptosis inducer [Ir(Cp*)(Bet)Cl]Cl ( Ir-Bet ) was developed by a metal-ligand synergistic enhancement (MLSE) strategy involving the reaction of [Ir(Cp*)Cl]2Cl2 with the natural product Betulin. The fusion of Betulin with iridium cyclopentadienyl (Ir-Cp*) species as Ir-Bet not only tremendously enhanced the antiproliferative activity toward cancer cells, but also activated ferritinophagy for iron homeostasis regulation by PI3K/Akt/mTOR cascade inhibition with a lower dosage of Betulin, and then evoked an immune response by nuclear factor kappa-B (NF-κB) activation of Ir-Cp* species. Further immunogenic cell death (ICD) occurred by remarkable ferroptosis through glutathione (GSH) depletion, glutathione peroxidase 4 (GPX4) deactivation and ferritinophagy. An in vivo vaccination experiment demonstrated desirable antitumor and immunogenic effects of Ir-Bet by increasing the ratio of cytotoxic T cells (CTLs)/regulatory T cells (Tregs). 相似文献
96.
An interlocked M_4 L_8 coordination cage was synthesized by coordination-driven self-assembly of palladium(Ⅱ) ions with aromatic amide bidentate ligands.The reaction of the ligand and the metal at 2:1 ratio led to the monomeric M_2 L_4 cage as the kinetic product,while the thermodynamic product M_4 L_8 cage was obtained by prolongating the reaction.This conve rsion and the interlocked structure was clearly revealed by using ~1 H NMR,mass spectrometry and X-ray crystallography.The driving force of interlocking was mainly attributed to the interactions(hydrogen bonding,aromatic stacking and electrostatic interaction) arising from the aptitude of flexibility of the amide ligand. 相似文献
97.
98.
赭曲霉毒素A(Ochratoxin A,OTA)是一种由赭曲霉、青霉菌等真菌产生的次级代谢产物,在自然界分布广泛,具有肝毒性、肾毒性、致癌、致突变作用。鉴于其危害的严重性和污染的广泛性,发展高灵敏度的OTA检测技术引起了研究者的广泛关注。该文阐述了近年来新型电化学传感技术在OTA 检测方面的发展及应用,全面综述了目前OTA电化学传感器的主要类型及其优缺点,并对其发展方向提出了展望,从而为基于OTA的电化学传感器的深入研究与应用提供了参考。 相似文献
99.
Jeong Young Su Lee Jaegi Chun Young-Bum Uhm Young Rang Sun Gwang-Min Kim Yong Min 《Journal of Radioanalytical and Nuclear Chemistry》2021,330(2):513-519
Journal of Radioanalytical and Nuclear Chemistry - The defects due to cold-rolling deformation in the advanced reduced-activation alloy (ARAA) have been analyzed using positron annihilation... 相似文献
100.
Zhen Wang Ziyang Li Tian Su Xiao Han Zhanwu Hou Yupeng Zheng Jiachen Liu Jun Xu Jeffy Yang Huadong Liu 《Electrophoresis》2021,42(6):793-799
Western blot (protein immunoblot) is a widely used analytical technique in molecular biology. Utilizing the specific recognizing primary antibody, proteins immobilized on various matrix are investigated by subsequent visualization steps, for example, by the horse radish peroxidase conjugated secondary antibody incubation. Methods to improve the sensitivity in protein identification or quantification are appreciated by biochemists. Herein, we report a new strategy to amplify Western blot signals by constructing a probe with proximal labeling and IgG targeting abilities. The R118G mutation attenuated the biotin-AMP binding affinity of the bacterial biotin ligase BirA*, offering a proximity-dependent labeling ability, which could be used as a signal amplifier. We built a BirA*-protein A fusion protein (BioEnhancer) that specifically binds to IgG and adds biotin tags to its proximal amine groups, enhancing the immunosignal of target proteins. In our experiments, the BioEnhancer system amplified the immunosignal by tenfold compared to the standard western blot. Additionally, our strategy could couple with other signal enhancement methods to further increase the western blot sensitivity. 相似文献