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91.
Tunable Surface‐Enhanced Raman Scattering from High‐Density Gold Semishell Arrays with Controllable Dimensions 下载免费PDF全文
Xianzhong Lang Dr. Jiaqi Li Xiaoguang Luo Yan Zhang Yin Yin Prof. Teng Qiu 《Chemphyschem》2014,15(2):337-343
A convenient reproducible technique is reported for the fabrication of large‐area gold semishell arrays by mechanically pressing porous anodic alumina (PAA) stamps into gold/polymer bilayer structures that serve as robust and cost‐efficient surface‐enhanced Raman‐scattering (SERS) substrates. The surface structure can be tuned further to optimize the enhancement factor according to optional PAA fabrication parameters and imprinting pressures. Finite‐difference time‐domain calculations indicate that the structure may possess excellent SERS characteristics due to the high density and abundance of hot spots. 相似文献
92.
纳米结构Au/Fe_2O_3的制备、表征及催化氧化性能 总被引:1,自引:0,他引:1
分别以纳米和块状氧化铁为载体,通过沉积沉淀法制备了Au/Nano-Fe2O3和Au/Bulk-Fe2O3,并对其进行了表征和催化氧化性能测试。结果表明:对于Au/Nano-Fe2O3,5 nm Au颗粒被尺寸相当的Nano-Fe2O3所包覆,形成新颖的类似核壳结构;对于Au/Bulk-Fe2O3,3 nm Au颗粒高度分散于Bulk-Fe2O3的表面。在1-苯乙醇的氧化反应中,Au/Nano-Fe2O3显示出比Au/Bulk-Fe2O3更好的催化活性。活性的增强主要与小尺寸的Nano-Fe2O3以及Au和Nano-Fe2O3更大的接触界面有关。相比于广泛受到重视的Au的尺寸效应来说,对于Au/Nano-Fe2O3而言,Fe2O3尺寸的影响更大。 相似文献
93.
A three-coordinate Ag(I) complex, [Ag(Mepzpy)(PAr3)]BF4·H2O(1, Mepzpy = 3-methyl-1-(2-pyridyl)pyrazole, PAr3 = tri(o-tolyl)phosphine), was synthesized from the reaction of Ag(CH3CN)4BF4, PAr3 and Mepzpy in CH3 CN at room temperature. The compound was characterized by UV-vis, NMR and X-ray single-crystal structure analysis. It crystallizes in triclinic space group P1 with a = 10.2251(5), b = 10.6014(5), c = 15.7012(5) , α = 92.963(3), β = 92.641(3), γ = 114.647(4)o, V = 1540.6(1) 3, Z = 2, Mr = 676.24, Dc = 1.458 g/cm3, F(000) = 688, μ = 6.187 mm-1, GOOF = 1.038, the final R = 0.0530 and w R = 0.1493 for 6371 observed reflections with I 2σ(I). Compound 1 is ionic. It is composed of a BF4- anion and a [Ag(Mepzpy)(PAr3)]+ cation. The Ag(I) ion adopts a distorted trigonal pyramidal coordination geometry defined by two nitrogen atoms and a phosphorous atom. The complex emits blue luminescence with maximum peaks at 470 nm in solid state at room temperature. 相似文献
94.
Yanli Li Peiran Zhao Dr. Teng Gong Han Wang Dr. Xingwu Jiang Hui Cheng Dr. Yanyan Liu Dr. Yelin Wu Prof. Wenbo Bu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(50):22726-22732
Redox homeostasis is one of the main reasons for reactive oxygen species (ROS) tolerance in hypoxic tumors, limiting ROS-mediated tumor therapy. Proposed herein is a redox dyshomeostasis (RDH) strategy based on a nanoplatform, FeCysPW@ZIF-82@CAT Dz, to disrupt redox homeostasis, and its application to improve ROS-mediated hypoxic tumor therapy. Once endocytosed by tumor cells, the catalase DNAzyme (CAT Dz) loaded zeolitic imidazole framework-82 (ZIF-82@CAT Dz) shell can be degraded into Zn2+ as cofactors for CAT Dz mediated CAT silencing and electrophilic ligands for glutathione (GSH) depletion under hypoxia, both of which lead to intracellular RDH and H2O2 accumulation. These “disordered” cells show reduced resistance to ROS and are effectively killed by ferrous cysteine-phosphotungstate (FeCysPW) induced chemodynamic therapy (CDT). In vitro and in vivo data demonstrate that the pH/hypoxia/H2O2 triple stimuli responsive nanocomposite can efficiently kill hypoxic tumors. Overall, the RDH strategy provides a new way of thinking about ROS-mediated treatment of hypoxic tumors. 相似文献
95.
Mengjiao Huang Dr. Juanjuan Yang Teng Wang Dr. Jia Song Jinglu Xia Dr. Lingling Wu Dr. Wei Wang Dr. Qiaoyi Wu Prof. Zhi Zhu Dr. Yanling Song Prof. Chaoyong Yang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(12):4830-4835
Immunotherapy has revolutionized cancer treatment, but its efficacy is severely hindered by the lack of effective predictors. Herein, we developed a homogeneous, low-volume, efficient, and sensitive exosomal programmed death-ligand 1 (PD-L1, a type of transmembrane protein) quantitation method for cancer diagnosis and immunotherapy response prediction (HOLMES-ExoPD-L1). The method combines a newly evolved aptamer that efficiently binds to PD-L1 with less hindrance by antigen glycosylation than antibody, and homogeneous thermophoresis with a rapid binding kinetic. As a result, HOLMES-ExoPD-L1 is higher in sensitivity, more rapid in reaction time, and easier to operate than existing enzyme-linked immunosorbent assay (ELISA)-based methods. As a consequence of an outstanding improvement of sensitivity, the level of circulating exosomal PD-L1 detected by HOLMES-ExoPD-L1 can effectively distinguish cancer patients from healthy volunteers, and for the first time was found to correlate positively with the metastasis of adenocarcinoma. Overall, HOLMES-ExoPD-L1 brings a fresh approach to exosomal PD-L1 quantitation, offering unprecedented potential for early cancer diagnosis and immunotherapy response prediction. 相似文献
96.
对小学科学课程标准与五年制专科小学教育专业“科学·化学”教学大纲中对化学知识内容的要求,以及小学《科学》和高等专科学校《科学·化学》教材中涉及的化学知识内容进行了对比。同时就五年制专科层次小学教育专业化学课程存在的问题进行了讨论,并提出了选择合适的课程教学内容、加强化学实验和化学教材建设、建立理论课程和实验教学新体系模块等建议。 相似文献
97.
Qi Teng Wenxiu Mao Dong Chen Zhen Wang Chen‐Ho Tung Zhenghu Xu 《Angewandte Chemie (International ed. in English)》2020,59(6):2220-2224
A rhodium(I)‐BINAP‐catalyzed highly enantioselective [2+2+2] cycloaddition of enynes with alkynes has been developed. Diverse fused tricyclic hydronaphthofuran scaffolds with three consecutive stereogenic centers were constructed in one step from easily available materials with excellent chemo‐, regio‐, diastereo‐, and enantioselectivity. Notable features of these reactions include 100 % atom economy, very broad scope, and mild reaction conditions. 相似文献
98.
Jing Zhang Meng Liu Chuanhua Wu Gaoyuan Zhao Peiqi Chen Lin Zhou Xingang Xie Ran Fang Huilin Li Xuegong She 《Angewandte Chemie (International ed. in English)》2020,59(10):3966-3970
The first total synthesis of the Euphorbia diterpenoid pepluanol B in both racemic and enantioenriched form involves 20 steps from a known bicyclic diol. This synthesis features an unprecedented bromo‐epoxidation to control the eight‐membered‐ring conformation. In addition, salient reactions for the construction of the tetracyclic backbone include a sterically challenging aldol reaction to establish the quaternary center, a ring closing metathesis (RCM) to forge the eight‐membered ring, and a diastereoselective cyclopropanation to assemble the embedded cyclopropane motif. 相似文献
99.
Chen Wu-Hua Xiong Jin-Hua Teng Xue Mi Jin-Xiao Hu Zhi-Biao Wang Haifeng Chen Zuofeng 《中国科学:化学(英文版)》2020,63(12):1825-1836
Science China Chemistry - A novel CoII-Fenton-like heterogeneous catalyst, (H3O)2[CoII(phen)(H2O)2]2[MoVI5O15(PO4)2]·4H2O (phen=1,10-phenanthroline, C12N2H8) (1), is synthesized and utilized... 相似文献
100.
Teng Xia Ju 《数学学报(英文版)》2009,25(5):831-844
In this paper, we show that if H is a finite-dimensional Hopf algebra such that H and H^* are semisimple, then gl.dim(A#σH)=gl.dim(A), where a is a convolution invertible cocycle. We also discuss the relationship of global dimensions between the crossed product A^#σH and the algebra A, where A is coacted by H. Dually, we give a sufficient condition for a finite dimensional coalgebra C and a finite dimensional semisimple Hopf algebra H such that gl.dim(C α H)=gl.dim(C). 相似文献