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101.
102.
An Unusual Triphenylphosphine Oxide Catalyzed Stereoselective 1,3‐Dichlorination of Unsaturated Ketoesters 下载免费PDF全文
Tian‐Yang Yu Yao Wang Peng‐Fei Xu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(1):98-101
An unusual Ph3PO‐catalyzed stereoselective 1,3‐dicholorination of an unsaturated ketoester has been developed. The novel activation mode involved in this cascade reaction can promote consecutively elusive transformations. The products were obtained with good yields and excellent stereoselectivities. This reaction makes important complementation to the limitations associated with the field of dichlorination. 相似文献
103.
Complex 3D microparticle, as an emerging and attractive field, has attracted more and more attention due to its versatile morphologies and broad range of applications. In this review, we provide an overall recent progress in 3D microparticles fabricated by microfluidic lithography. This review will focus on the synthesis mechanisms, synthesis process, the resultant 3D microparticles, and their applications. Finally, we will look into the future trends in complex 3D microparticles. This review will be beneficial for researchers in numerous fields, including functional materials, sensors, encryption, and biomedical engineering. 相似文献
104.
Hui Shao Xiaonan Gao Zhong‐Tian Wang Ziwei Gao Yu‐Ming Zhao 《Angewandte Chemie (International ed. in English)》2020,59(19):7419-7424
A divergent synthetic approach to six Ganoderma meroterpenoids, namely ganocins A–C, ganocochlearins C and D, and cochlearol T, has been developed for the first time. This synthetic route features a two‐phase strategy which includes early‐stage rapid construction of a common planar tricyclic intermediate followed by highly selective late‐stage transformations into various Ganoderma meroterpenoids. Key to the strategy are a bioinspired intramolecular hetero‐Diels–Alder reaction and Stahl‐type oxidative aromatization, allowing efficient formation of the common tricyclic phenol intermediate. A nucleophilic dearomatization of the phenol unit, combined with a regioselective 1,4‐reduction of the resulting dienone, enabled rapid access to ganocins B and C. Additionally, site‐selective Mukaiyama hydration, followed by an intramolecular oxa‐Michael addition/triflation cascade, served as a key strategic element in the chemical synthesis of ganocin A. 相似文献
105.
Yi Ding Yan Wu Ying Tian Yuzeng Xu Minna Hou Bo Zhou Jingshan Luo Guofu Hou Ying Zhao Xiaodan Zhang 《Journal of Energy Chemistry》2021,(7):48-54
Guanidinium (GA) cations are intentionally introduced in MAPbl3 perovskite by considering its potential capability of stabilizing the material through plenty of... 相似文献
106.
We conduct extensive research into the structures of BexZn1-xOO ternary alloys in a pressure range of 0-60GPa,using the ab initio total energy evolutionary algorithm and total energy calculations,finding several metastable structures.Our pressure-composition phase diagram is constructed using the enthalpy results.In addition,we calculate the electronic structures of the BexZn1-xOO structures and investigate the bandgap values at varying pressures and Be content.The calculated results show that the bandgap of the BexZn1-xOO ternary alloys increases with an increase in Be content at the same pressure.Moreover,the bandgap of the BexZn1-xOO ternary alloys increases with the increasing pressure with fixed Be content.At the same Be content,the formation enthalpy of the BexZn1-xOO ternary alloys first decreases,then increases with the increasing pressure. 相似文献
107.
280mm×280mm口径单脉冲过程电光开关 总被引:4,自引:1,他引:3
用于高功率惯性约束聚变(ICF)激光驱动器的大口径电光开关均采用等离子体电极泡克耳斯盒。与传统的等离子体电极电光开关原理不同,单脉冲过程驱动电光开关没有独立的大电流等离子体发生单元,而只是通过具有较高幅值的正负开关脉冲完成对大口径电光开关的驱动。介绍单脉冲过程驱动等离子体电极泡克耳斯盒电光开关的设计,并建立280 mm×280 mm口径电光开关实验平台,利用连续激光器测试了电光开关特性,实验测得该电光开关中心处开关效率为99.3%,开关上升时间为90 ns。 相似文献
108.
Oxidative desulfurization (ODS) is the promising new method for super deep desulfurization of fuel oil. The oxidative desulfurization performance of the metal-N4-chelates metallophthalocyanines (MPcs) is related to the chemical properties of conjugate structures and the central metal ions. Herein, a biomimetic catalytic system composed of metallophthalocyanines (MPcR4, M = Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II); R = -H, -COOH, -NO2, -NH2) and molecular O2 was performed to study the influence of MN4-type coordination structure in metallophthalocyanines for the degradation of dibenzothiophene (DBT) in model oil containing n-octane. The results reveal that the conjugate structures and the center metal ions of metallophthalocyanines played key roles in oxidative desulfurization performance. The inductive effect of different R substituents strongly affected the electron cloud distribution of the conjugate structures and the catalytic performance. Moreover, the catalytic activity of MPcs, which is related to the d electronic configuration and ligand-field effects, does not sequentially increase with the increase in the d electron number of central metal ions. 相似文献
109.
Birui Shi Yan Zhang Baolin Huang Huiping Lin Qiong Zhou Yujue Wang Zheng Cai Menghua Liu 《Molecules (Basel, Switzerland)》2022,27(3)
With the widespread clinical use of drug combinations, the incidence of drug–drug interactions (DDI) has significantly increased, accompanied by a variety of adverse reactions. Drug transporters play an important role in the development of DDI by affecting the elimination process of drugs in vivo, especially in the pathological state. Tubulointerstitial fibrosis (TIF) is an inevitable pathway in the progression of chronic kidney disease (CKD) to end-stage renal disease. Here, the dynamic expression changes of eleven drug transporters in TIF kidney have been systematically investigated. Among them, the mRNA expressions of Oat1, Oat2, Oct1, Oct2, Oatp4C1 and Mate1 were down-regulated, while Oat3, Mrp2, Mrp4, Mdr1-α, Bcrp were up-regulated. Pearson correlation analysis was used to analyze the correlation between transporters and Creatinine (Cr), OCT2 and MATE1 showed a strong negative correlation with Cr. In contrast, Mdr1-α exhibited a strong positive correlation with Cr. In addition, the pharmacokinetics of cimetidine, ganciclovir, and digoxin, which were the classical substrates for OCT2, MATE1 and P-glycoprotein (P-gp), respectively, have been studied. These results reveal that changes in serum creatinine can indicate changes in drug transporters in the kidney, and thus affect the pharmacokinetics of its substrates, providing useful information for clinical use. 相似文献
110.
Experiment and simulation were used to study the flow fields of a liquid-solid-solid three-phase system in a draft-tube stirred reactor with a six-flat-bladed t... 相似文献