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951.
Three Dimensionally Ordered Mesoporous Carbon as a Stable,High‐Performance Li–O2 Battery Cathode 下载免费PDF全文
Jin Xie Xiahui Yao Qingmei Cheng Ian P. Madden Paul Dornath Chun‐Chih Chang Prof. Dr. Wei Fan Prof. Dr. Dunwei Wang 《Angewandte Chemie (International ed. in English)》2015,54(14):4299-4303
Enabled by the reversible conversion between Li2O2 and O2, Li–O2 batteries promise theoretical gravimetric capacities significantly greater than Li‐ion batteries. The poor cycling performance, however, has greatly hindered the development of this technology. At the heart of the problem is the reactivity exhibited by the carbon cathode support under cell operation conditions. One strategy is to conceal the carbon surface from reactive intermediates. Herein, we show that long cyclability can be achieved on three dimensionally ordered mesoporous (3DOm) carbon by growing a thin layer of FeOx using atomic layer deposition (ALD). 3DOm carbon distinguishes itself from other carbon materials with well‐defined pore structures, providing a unique material to gain insight into processes key to the operations of Li–O2 batteries. When decorated with Pd nanoparticle catalysts, the new cathode exhibits a capacity greater than 6000 mAh gcarbon?1 and cyclability of more than 68 cycles. 相似文献
952.
Yao Qian Zhiyue Han Yinghao Zhang Zhiming Du Yan Zhao Yuezhen Yang Jingchang Zhang 《Journal of heterocyclic chemistry》2016,53(2):651-657
1,5‐diaminotetrazolium chloride (DATC) and 1,5‐diaminotetrazolium sulfate (DATS) were synthesized in this work. The structures of DATS and DATC were characterized. The single crystal of DATS was first cultured, and its structure was analyzed. The thermal behavior of DATS was investigated. The activation energy and pro‐exponential factor were calculated, Ek = 120.86 KJ/mol, Ak = 1012.96 s?1. The density, heat of formation, detonation pressure, and detonation velocity of DATS were first calculated. The detonation pressure and detonation velocity of DATS are P = 11.877 GPa, D = 5.617 km s?1, which are smaller than those of 1,5‐diaminotetrazolium nitrate (DATN) (P = 33.3GPa, D = 8.77 km s?1). 相似文献
953.
A Multi‐signal Fluorescent Probe with Multiple Binding Sites for Simultaneous Sensing of Cysteine,Homocysteine, and Glutathione 下载免费PDF全文
Guo‐xing Yin Ting‐ting Niu Ya‐bing Gan Ting Yu Dr. Peng Yin Prof. Hai‐min Chen Prof. You‐yu Zhang Prof. Hai‐tao Li Prof. Shou‐zhuo Yao 《Angewandte Chemie (International ed. in English)》2018,57(18):4991-4994
A novel fluorescent probe was developed by integrating chlorinated coumarin and benzothiazolylacetonitrile and exploited for simultaneous detection of cysteine (Cys), homocysteine (Hcy), and glutathione (GSH). Featuring four binding sites and different reaction mechanisms for different biothiols, this probe exhibited rapid fluorescence turn‐on for distinguishing Cys, Hcy, and GSH with 108‐, 128‐, 30‐fold fluorescence increases at 457, 559, 529 nm, respectively, across different excitation wavelengths. Furthermore, the probe was successfully applied to the fluorescence imaging of endogenous Cys and GSH and exogenous Cys, Hcy, and GSH in living cells. 相似文献
954.
Minxia Huang Beiyang Yao Manhua Jiang Fuzhou Sun Jinsong You Fangfang Huang Yanping Zhao Shuming Wu Xinqian He Xuezhi Song 《Journal of mass spectrometry : JMS》2022,57(4):e4821
Two unknown solution degradants were found during the dissolution testing in 0.1-M HCl for olmesartan medoxomil (OLM) tablets. The structure of the degradants was identified and characterized by liquid chromatography–ultraviolet (LC–UV), liquid chromatography with tandem mass spectrometry (LC–MS/MS), and nuclear magnetic resonance (NMR) and demonstrated to be cyclization of tetrazole and benzene in the olmesartan (OL) and OLM structures. A series of studies including stress studies, simulation studies, and mechanism-based studies were performed to reveal the potential mechanisms that lead to the formation of the unknown degradants. The study results demonstrated that the degradation was catalyzed with radicals that originated from the metal ions leached from the inner surface of high-performance liquid chromatography (HPLC) glass vials with dissolved oxygen under acidic condition. Prerinsing the glass vials with acidic solution dissolved with EDTA can effectively avoid the generation of such oxidative impurities. The present work provides new insights into the understanding of degradation pathways of OLM, which might support the development of OLM tablets. 相似文献
955.
担载材料对TiO2薄膜光催化活性的影响 总被引:11,自引:0,他引:11
TiO_2 nanocrystalline films were prepared on glass, ITO and p-Si substrates. Degradation of Rhodamine B was used to assess the photocatalytic activity of the films. It was found that photocatalytic activity of TiO2 films on ITO and p-Si are higher than that on glass, and the film grown on ITO is the best. In addition, crystalline phases and surface morphology of TiO_2films were also affected by different substrates. Surface Photovoltage Spectra was used to analyze surface states and energy levels of the films. Separation of photogenerate electrons and holes was promoted due to matching of the energy levels between TiO_2 films and ITO as well as p-Si. High photocatalytic activity was then obtained because more photogenerate electrons and holes took part in photocatalytic reaction on TiO_2 surfaces. 相似文献
956.
957.
我们制得了硫氨酸轮与二苯并-18-冠-6(DBC)的固体络合物,进行了元素分析、X光衍射、红外光谱、紫外光谱和差热、热重分析,对其合成条件及性质进行了一些探讨。 相似文献
958.
959.
采用基于密度泛函理论的第一性原理方法,研究了本征石墨烯和掺杂石墨烯对环氧树脂的吸附行为.主要研究了四种石墨烯:本征石墨烯(P-graphene)、B掺杂的石墨烯(B-graphene)、N掺杂的石墨烯(N-graphene)和O掺杂的石墨烯(O-graphene).结果表明,O掺杂有利于降低石墨烯对环氧树脂的吸附能.从电子结构上看,O掺杂的石墨烯与环氧树脂发生轨道杂化,且二者的电荷密度明显重叠,说明O掺杂的石墨烯与环氧树脂的相容性好.因此,在环氧树脂涂层中加入O掺杂的石墨烯有望成为一种提高环氧树脂涂层机械性能和抗腐蚀性能的方法 . 相似文献
960.
Capillary electrophoretic studies on quantum dots and histidine appended peptides self‐assembly 下载免费PDF全文
Jianhao Wang Jingyan Li Yao Chen Yiwan Teng Cheli Wang Jinchen Li Li Liu Bingyu Dong Lin Qiu Pengju Jiang 《Electrophoresis》2015,36(19):2419-2424
Herein, we designed four peptides appended with different numbers of histidine (Hisn‐peptide). We launched a systematic investigation on quantum dots (QDs) and Hisn‐peptide self‐assembly in solution using fluorescence coupled CE (CE‐FL). The results indicated that CE‐FL was a powerful method to probe how ligands interaction on the surface of nanoparticles. The self‐assembly of QDs and peptide was determined by the numbers of histidine. We also observed that longer polyhistidine tags (n ≤ 6) could improve the self‐assembly efficiency. Furthermore, the formation and separation of QD‐peptide assembly were also studied by CE‐FL inside a capillary. The total time for the mixing, self‐assembly, separation, and detection was less than 10 min. Our method greatly expands the application of CE‐FL in QDs‐based biolabeling and bioanalysis. 相似文献