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排序方式: 共有594条查询结果,搜索用时 15 毫秒
81.
Shuai Zhao Prof. Shaohua Zhang Huijun Hu Yangchang Cheng Kexuan Zou Prof. Jie Song Dr. Jinqi Deng Prof. Lele Li Prof. Xiao-Bing Zhang Prof. Guoliang Ke Prof. Jiashu Sun 《Angewandte Chemie (International ed. in English)》2023,62(24):e202303121
Mature microRNAs (miRNAs) in extracellular vesicles (EVs) are involved in different stages of cancer progression, yet it remains challenging to precisely detect mature miRNAs in EVs due to the presence of interfering RNAs (such as longer precursor miRNAs, pre-miRNAs) and the low abundance of tumor-associated miRNAs. By leveraging the size-selective ability of DNA cages and polyethylene glycol (PEG)-enhanced thermophoretic accumulation of EVs, we devised a DNA cage-based thermophoretic assay for highly sensitive, selective, and in situ detection of mature miRNAs in EVs with a low limit of detection (LoD) of 2.05 fM. Our assay can profile EV mature miRNAs directly in serum samples without the interference of pre-miRNAs and the need for ultracentrifugation. A clinical study showed that EV miR-21 or miR-155 had an overall accuracy of 90 % for discrimination between breast cancer patients and healthy donors, which outperformed conventional molecular probes detecting both mature miRNAs and pre-miRNAs. We envision that our assay can advance EV miRNA-based diagnosis of cancer. 相似文献
82.
Zhang G Huang S Xiao Z Chen Q Gan L Wang Z 《Journal of the American Chemical Society》2008,130(38):12614-12615
Azafullerene was prepared by addition of hydroxylamine to a cage-opened fullerendione derivative and subsequent PCl5 induced rearrangement processes. X-ray structures were obtained for the azafullerene and its azafulleroid precursor. 相似文献
83.
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
84.
The electrochemical reduction process of Dy ion on tungsten electrode at 1103 K in Dy2O3-LiF-DyF3 molten system was studied by cyclic voltammetry, chronoamperometry, and chronopotentiometry methods with a three-electrode system on the electrochemical workstation AUTOLAB. The results showed that Dy3+ could be deposited at around ?0.75 V on inert W electrode compared with platinum electrode. The reduction process of Dy ion on W electrode occurred in a single step with the exchange of three electrons because one reduction peak was observed, and the calculated transfer electron number was three. Chronoamperograms indicated that the nucleation process of dysprosium ions was instantaneous three-dimensional nucleation on a tungsten electrode. The cathode electrochemical process on the tungsten electrode was controlled by the diffusion of ions, and the diffusion coefficient was 1.159 × 10?4 cm2/s, which was calculated from a chronopotentiogram. 相似文献
85.
86.
Interface Engineering of MoS2/Ni3S2 Heterostructures for Highly Enhanced Electrochemical Overall‐Water‐Splitting Activity 下载免费PDF全文
Dr. Jian Zhang Dr. Tao Wang Dr. Darius Pohl Dr. Bernd Rellinghaus Dr. Renhao Dong Dr. Shaohua Liu Dr. Xiaodong Zhuang Prof. Xinliang Feng 《Angewandte Chemie (International ed. in English)》2016,55(23):6702-6707
To achieve sustainable production of H2 fuel through water splitting, low‐cost electrocatalysts for the hydrogen‐evolution reaction (HER) and the oxygen‐evolution reaction (OER) are required to replace Pt and IrO2 catalysts. Herein, for the first time, we present the interface engineering of novel MoS2/Ni3S2 heterostructures, in which abundant interfaces are formed. For OER, such MoS2/Ni3S2 heterostructures show an extremely low overpotential of ca. 218 mV at 10 mA cm?2, which is superior to that of the state‐of‐the‐art OER electrocatalysts. Using MoS2/Ni3S2 heterostructures as bifunctional electrocatalysts, an alkali electrolyzer delivers a current density of 10 mA cm?2 at a very low cell voltage of ca. 1.56 V. In combination with DFT calculations, this study demonstrates that the constructed interfaces synergistically favor the chemisorption of hydrogen and oxygen‐containing intermediates, thus accelerating the overall electrochemical water splitting. 相似文献
87.
A new self-assembled catalyst based on titanium complex has been developed for the effective enantioselective cyano-ethoxycarbonylation of aldehydes. The self-assembled catalyst was readily prepared from (R)-3,3′-bis((methyl((S)-1-phenylethyl)amino)methyl)-1,1′-binaphthyl-2,2′-diol (1h), N-((1S,2R)-2-hydroxy-1,2-diphenylethyl)acetamide (2b), and tetraisopropyl titanate (Ti(OiPr)4). A variety of aromatic aldehydes, aliphatic aldehydes, and α,β-unsaturated aldehydes were found to be suitable substrates in the presence of the self-assembled titanium catalyst (5 mol % 1h, 5 mol % 2b, and 5 mol % Ti(OiPr)4). The desired cyanohydrin ethyl carbonates were afforded with high isolated yields (up to 95%) and moderate to good enantioselectivities (up to 92% ee) under mild conditions (at −15 °C). A possible catalytic cycle based on the experimental observation was proposed. 相似文献
88.
本文报道了在D261OCl~-树脂的存在下,仲醇在三相体系中,用次氯酸钙进行氧化,反应在25℃—35℃下进行,生成相应的酮,产率在33—48%之间。 相似文献
89.
meso—四(4—溴苯基)卟啉与Cd^2+的显色反应的研究 总被引:2,自引:0,他引:2
研究了Tween—80存在时,非水溶性meso—四(—4—溴苯基)卟啉(TBrPP)与镉络合显色反应的条件以及对络合物光敏性的机理做了一些初步探讨。络合物摩尔组成比为1:1,ε′为4.5×10~5,镉量在0~0.36μg·ml~(-1)有较好的线性关系,线性回归方程A=0.00034+0.161C,相关系数为0.9997,稳定常数为2.6×10~7,用于烟草、茶叶、环境分析标准水样中痕量镉的测定,结果满意。 相似文献
90.