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991.
A Computational Study on Iridium‐Catalyzed Production of Acetic Acid from Ethanol and Water Solution
The mechanism for the production of acetic acid from ethanol and water mixture catalyzed by iridium catalyst has been theoretically investigated. The cooperation of the iridium center and bpyO ligand is highlighted, which plays an important role in the catalytic activity. The hydrogen release from the iridium center is the rate‐determining step, with an energy barrier of 22.5 kcal/mol. The electronic structure analysis suggests electron‐donating substituents could decrease the energy barrier. 相似文献
992.
Alzheimer’s disease(AD)is a neurodegenerative disorder characterized by the deposition ofβ-amyloid peptide(Aβ)in the brain tissues,and an imbalance in the oxidant-antioxidant system.Compounds with antioxidant activity and the ability to inhibit Aβaggregation therefore potentially treat AD.In this study,we designed an iron-porphyrin containing bifunctional peptide(BP,Deuterohemin-AlaHisThrValGluLysLeuProPhePheAsp)based on natural microperoxidase-11(MP-11)and typicalβ-sheet breaker LPFFD(iAβ5p).This BP substantially reduced the aggregation of Aβand caused oligomer disassembly,by binding Aβwith affinity constant of 9.07μmol/L.Furthermore,it showed a neuroprotective effect on Aβ25—35 induced toxicity in SH-SY5Y cells,and significantly alleviated Aβ-induced paralysis and extended lifespan in Aβ1-42 transgenic C.elegans(CL4176).It also showed a potent peroxidase activity of 20.8 U/mg,and scavenged free radicals both in and in vivo.In addition,BP up-regulated the levels of hsp16.2,hsp16.41,and hsp12.6 mRNAs to 183.26%,160.16%,and 162.64%respectively,and down-regulated that of hsp70 to 36.76%in C.elegans.Taken together,the synthetic BP inhibited Aβaggregation and showed antioxidant activity,indicating the therapeutic potential of novel peptide drugs against AD. 相似文献
993.
Using dextran as both reductant and stabilizing agent, nanopetals(ZnO-Au NPs) were easily synthesized and possessed a petal-like morphology. The feature structure and size of such ZnO-Au NPs were adjustable by regulating the amount of chloroauric acid(HAuCl4). Moreover, the electrochemical property of the obtained NPs was evaluated by being immobilized on the glassy carbon electrode(GCE), which performed both high sensitivity and stability in dopamine(DA) determinations. Furthermore, the as-prepared ZnO-Au NPs could also detect DA and uric acid(UA) simultaneously in the mixture without interference, indicating good selectivity and showing promising potential in biosensing. 相似文献
994.
The development of a simple directly wearable approach for the rapid, specific and sensitive determination of biomarkers is of great importance to a variety of biomedical applications. Dental floss can provide a unique device platform for sensing of oral biomarkers. We show here for the first time the development of a smart dental floss for biosensing of glucose. The sensor was made by painting carbon graphite ink and Ag/AgCl ink on dental floss. Via the immobilization of glucose oxidase, we show the detection of glucose with a detection range of 0.048 mM to 19.5 mM and a response time of about 2 min. It is expected that our results could provide new exciting opportunities for the development of various flexible smart sensing devices in oral health applications. 相似文献
995.
Jiaji Cheng Haodong Wang Xu Wang Shaoxiang Li Yue Zhou Feng Zhang Yong Wang Wenjuan Qu Dong Wang Xiujiang Pang 《先进技术聚合物》2019,30(12):3091-3098
Ramie fiber (RF) with excellent tensile strength was treated by a flame retardant and obtained the modified RF (MRF) that is incombustible. Then, MRF was used to improve the performance of rigid polyurethane foams (RPUF). The mechanical properties of the composite were investigated by compressive strength test and shear stress test. The fire characteristics were studied using a cone calorimeter. And the thermal decomposition and flammable properties were further evaluated using thermogravimetric analysis and limiting oxygen index. The results showed that MRF improve the mechanical properties of RPUF and eliminate the harm of flammability of RF on the RPUF. 相似文献
996.
Sun Yue Zhao Mengyuan Liu Yutong Fu Liye Li Siyu Yang Yifei 《Journal of Solid State Electrochemistry》2019,23(2):583-590
Journal of Solid State Electrochemistry - Erythromycin (ERY) molecular imprinted polymer was prepared on the surface of Au electrode modified with Ni and Au nanoclusters (MIP/AuNCs/Ni/Au) via... 相似文献
997.
Guangda Xu Guoqiang Yang Yue Wang Pan‐Lin Shao Jia Ning Nicolette Yau Bing Liu Yunbo Zhao Ye Sun Xinxin Xie Shuo Wang Yao Zhang Lixin Xia Yu Zhao 《Angewandte Chemie (International ed. in English)》2019,58(40):14082-14088
We present an economical catalytic procedure to convert readily available 1,2‐diaminobenzenes and terminal epoxides into valuable 1,2,3,4‐tetrahydroquinoxalines in a highly enantioselective fashion. This procedure operates through relay zinc and iridium catalysis, and achieves redox‐neutral and stereoconvergent production of valuable chiral heterocycles from racemic starting materials with water as the only side product. The use of commercially available reagents and catalysts and a convenient procedure also make this catalytic method attractive for practical application. 相似文献
998.
999.
The imidazo[1,2‐a]pyridines are an important target in organic synthetic chemistry and have attracted critical attention of chemists mainly due to the discovery of the interesting properties exhibited by a great number of imidazo[1,2‐a]pyridine derivatives. Although lots of synthetic methods of imidazo[1,2‐a]pyridines have been developed in the past years, the chemistry community faces continuing challenges to use green reagents, maximize atom economy and enrich the functional group diversity of product. Undoubtedly, with its low cost and lack of environmentally hazardous byproducts, cascade reactions and C?H functionalizations are ideal strategies for this field. In this record we highlight some of our progress toward the goal to synthesis of imidazo[1,2‐a]pyridine derivatives through carbene transformations or C?H functionalizations. 相似文献
1000.
Wang Yue Wang Yadi Huang Lina Liu Xiangyong Hu Jun Lü Junhong 《Analytical and bioanalytical chemistry》2019,411(27):7157-7164
Analytical and Bioanalytical Chemistry - Endothelial damage is a major manifestation in many forms of heart and lung injuries induced by lipopolysaccharide (LPS), but the biochemical responses and... 相似文献