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排序方式: 共有646条查询结果,搜索用时 15 毫秒
641.
Rurong Yu Xinyu Zhang Dr. Feiyue Hao Dr. Zhengneng Jin Dr. Guyue Liu Prof. Dr. Guoliang Dai Prof. Dr. Jiashou Wu 《European journal of organic chemistry》2023,26(15):e202300071
A novel cobalt-catalyzed reduction of 2-pyridyl ketones and related heteroaryl compounds using formate as reductant was developed. Ketone substrate is activated by chelation with cobalt, which makes the present method highly selective. A possible reaction mechanism is proposed. 相似文献
642.
Nuwayo Eric Munyaneza Carlos Posada Zhen Xu Vincenzo De Altin Popiolek Griffin Paddock Charles McKee Dr. Guoliang Liu 《Angewandte Chemie (International ed. in English)》2023,62(36):e202307042
Polystyrene (PS) is one of the least recycled large-volume commodity plastics due to bulkiness of foam products and associated contaminants. PS recycling is also severely hampered by the lack of financial incentive, limited versatility, and poor selectivity of existing methods. To this end, herein we report a thermochemical recycling strategy of “degradation-upcycling” to synthesize a library of high-value aromatic chemicals from PS wastes with high versatility and selectivity. Two cascade reactions are selected to first degrade PS to benzene under mild temperatures, followed by the derivatization thereof utilizing a variety of acyl/alkyl and sulfinyl chloride additives. To demonstrate the versatility, nine ketones and sulfides of cosmetic and pharmaceutical relevance were prepared, including propiophenone, benzophenone, and diphenyl sulfide. The approach is also amenable to sophisticated upcycling reaction designs and can produce desired products stepwise. The facile and versatile approach will provide a scalable and profitable methodology for upcycling PS waste into value-added chemicals. 相似文献
643.
Shuyi Yang Wensheng Zhang Guoliang Pan Jiaying Chen Jiayi Deng Ke Chen Xianglun Xie Dongxue Han Mengjiao Dai Li Niu 《Angewandte Chemie (International ed. in English)》2023,62(43):e202312076
The effective conversion of carbon dioxide (CO2) and nitrogen (N2) into urea by photocatalytic reaction under mild conditions is considered to be a more environmentally friendly and promising alternative strategies. However, the weak adsorption and activation ability of inert gas on photocatalysts has become the main challenge that hinder the advancement of this technique. Herein, we have successfully established mesoporous CeO2-x nanorods with adjustable oxygen vacancy concentration by heat treatment in Ar/H2 (90 % : 10 %) atmosphere, enhancing the targeted adsorption and activation of N2 and CO2 by introducing oxygen vacancies. Particularly, CeO2-500 (CeO2 nanorods heated treatment at 500 °C) revealed high photocatalytic activity toward the C−N coupling reaction for urea synthesis with a remarkable urea yield rate of 15.5 μg/h. Besides, both aberration corrected transmission electron microscopy (AC-TEM) and Fourier transform infrared (FT-IR) spectroscopy were used to research the atomic surface structure of CeO2-500 at high resolution and to monitor the key intermediate precursors generated. The reaction mechanism of photocatalytic C−N coupling was studied in detail by combining Density Functional Theory (DFT) with specific experiments. We hope this work provides important inspiration and guiding significance towards highly efficient photocatalytic synthesis of urea. 相似文献
644.
Xingyu Chen Guoliang Li Weipeng Zhang Jiayi Ou Hecheng Li Yiqi Huang Shuirong He Jiazhen Zhou Zhiqiang Zhao Jiabin Chen Xiaojing Meng Lili Liu 《Biomedical chromatography : BMC》2023,37(1):e5523
Occupational chronic cadmium poisoning (OCCP) can cause irreversible organ damage. Currently, no effective treatment is available for OCCP, and effective and sensitive biomarkers for treatment evaluation are still lacking. In this study, metabolomics techniques were used to analyze changes in endogenous metabolites in the urine of patients with OCCP after 15 years of treatment. Thirty urine samples from female patients with OCCP and healthy female controls (n = 15 per group) were assessed using gas chromatography–time-of-flight mass spectrometry and ultra-high-performance liquid chromatography–Q-Exactive mass spectrometry. The OCCP group had higher concentrations of blood urea nitrogen and urinary cadmium but near-normal urinary concentrations of β2-microglobulin and retinol-binding protein. Compared with the control group, the OCCP group had 66 significantly different metabolites with a variable importance in projection score >1 and p < 0.05. These differential metabolites were involved in various metabolic pathways, such as creatine metabolism, nicotinate and nicotinamide metabolism, the pentose phosphate pathway, d -glutamine and d -glutamate metabolism, and amino acid metabolism. Compared with the control group, the OCCP group had significantly higher urinary concentrations of creatine, glutamic acid, quinolinic acid and nicotinic acid. In a receiver operator characteristic analysis, the area under the curve of creatine was higher than those for glutamic acid, quinolinic acid and nicotinic acid, indicating that urinary concentrations of creatine could be used as a sensitive biomarker for the diagnosis and prognosis of OCCP and for monitoring its treatment. 相似文献
645.
Ze-Jiu Diao Si-Yi Liu Hui Wen Dr. Guoliang Liu Tao Yang Jing-Jing Li Prof. Xiao-Qin Liu Prof. Lin-Bing Sun 《Angewandte Chemie (International ed. in English)》2023,62(21):e202301739
Stimuli-responsive porous materials have captured much attention due to the on-demand tunable properties. Most reported stimuli-responsive porous materials are based on molecule isomerism or host-guest interaction, and it is highly desired to develop new types based on different responsive mechanism. Herein, inspired by natural cells which have the ability to fuse and divide induced by external stimulation, we report a new type of stimuli-responsive porous material based on detachment mechanism. A detachable porous organic polymer, namely DT-POP-1, is fabricated from the polymerization of anthracene-containing monomer (AnMon) when irradiated by 365 nm UV light. DT-POP-1 can detach into the monomer AnMon when irradiated with 275 nm UV light or heat. Such polymerization/detachment is reversible. The detachment results in a big difference in porosity and adsorption capacity, making the present detachable porous polymer highly promising in adsorptive separation and drug delivery. 相似文献
646.
Yao Yin Wei Xie Dr. Mengyi Xiong Yingying Gao Qin Liu Prof. Da Han Prof. Guoliang Ke Prof. Xiao-Bing Zhang 《Angewandte Chemie (International ed. in English)》2023,62(44):e202309837
The accurate, rapid, and sensitive identification of cancer cells in complex physiological environments is significant in biological studies, personalized medicine, and biomedical engineering. Inspired by the naturally confined enzymes on fluid cell membranes, a f luidly confin ed CRISPR-based D NA reporter (FINDER) was developed on living cell membranes, which was successfully applied for rapid and sensitive cancer cell identification in clinical blood samples. Benefiting from the spatial confinement effect for improved local concentration, and membrane fluidity for higher collision efficiency, the activity of CRISPR-Cas12a was, for the first time, found to be significantly enhanced on living cell membranes. This new phenomenon was then combined with multiple aptamer-based DNA logic gate for cell recognition, thus a FINDER system capable of accurate, rapid and sensitive cancer cell identification was constructed. The FINDER rapidly identified target cells in only 20 min, and achieved over 80 % recognition efficiency with only 0.1 % of target cells presented in clinical blood samples, indicating its potential application in biological studies, personalized medicine, and biomedical engineering. 相似文献