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61.
62.
Ming-Wei Hong Li Song Yi Zhao Lai-Shun Qin Cong-Yong Wang Hong-Sheng Shi Jia-Yu Guo Xiao-Dong Tao Kang-Ying Shu Wen-Xiang Chai 《Journal of Cluster Science》2014,25(6):1627-1640
A series of strongly phosphorescent copper(I) halide complexes, namely [Cu(μ-X)POP]2 (X = Cl (1), Br (2), I (3), Br0.5Cl0.5 (4), POP = bis[2-(diphenylphosphino)phenyl]ether), have been synthesized by reacting CuX with the diphosphine ligand in 1:1 molar ratio. All complexes were characterized by spectroscopic analysis (IR, UV–Vis), elemental analysis, and photoluminescence study. Single-crystal X-ray diffraction revealed that complex 2 is a dinuclear structure which is constructed by two μ-X bridges and two POP ligands as μ2 bridges. Other complexes were determined as isologues of complex 2 by powder X-ray diffraction and elemental analysis. All complexes exhibit intense blue-green phosphorescence with a lifetime of ~1 μs in the solid state. The halogen-mixed complex presents a lightly change in the luminescence comparing to that of parent complexes. The excited states of all complexes have been assigned as halide-to-ligand charge transfer state mixed metal-to-ligand charge transfer character based on the time-dependent density functional theory calculations. All complexes are thermally stable according to thermogravimetric analysis so that they are suitable for applying in luminescent devices. 相似文献
63.
Construction of Shallow Surface States through Light Ni Doping for High‐Efficiency Photocatalytic Hydrogen Production of CdS Nanocrystals 下载免费PDF全文
Shuo Li Lijing Zhang Tengfei Jiang Liping Chen Prof.Dr. Yanhong Lin Prof. Dr. Dejun Wang Prof. Dr. Tengfeng Xie 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(1):311-316
Ni‐doped CdS nanowires were synthesized by a simple one‐step method. X‐ray diffraction, X‐ray photoelectron spectroscopy, and photoluminescence spectroscopy confirmed that light Ni doping can form shallow surface states due to the presence of substitutional Ni ions, and heavy Ni doping can form deep surface states due to the presence of interstitial Ni ions. Surface photovoltage spectroscopy and transient photovoltage measurements revealed that the shallow surface states can prolong the lifetime of the photogenerated charge carriers, whereas the deep surface states lead to recombination of the photogenerated charge carriers. The relationship between different surface states and the photocatalytic performance of CdS nanocrystals are discussed. The enhanced density of shallow surface states due to light Ni doping significantly promotes photocatalytic H2 production. 相似文献
64.
Bao-Shan Chai Chang-Ling Liu Hui-Chao Li Shao-Wu Liu Ying Xu Yu-Quan Song Jun-Biao Chang 《中国化学快报》2014,25(1):137-140
Pyriminostrobin, a new acaricide, was discovered in our previous studies. Because introducing fluorine into organic compounds can increase bioactivity, pyriminostrobin was modified as a series of strobilurin-pyrimidine derivatives for biological screening. The compounds were characterized by 1H NMR, MS and elemental analysis. Preliminary bioassays demonstrated that compounds 7e and 7i exhibited significant control against Tetranychus cinnabarinus (Boisd.) at 0.625 mg L^-1, and their acaricidal potencies were higher than pyriminostrobin in a greenhouse. The relationship between structure and acaricidal activity was also studied. 相似文献
65.
Structural modifications of 3-OH in the glucose moiety of dapagliflozin(1), an approved potent sodium-dependent glucose transporter 2(SGLT2) inhibitor, led to 3-oxodapagliflozin(16), a highly potent and more selective SGLT2 inhibitor[IC50(hSGLT1)/IC50(hSGLT2)=2851 for compound 16 vs. 843 for compound 1]. 3-Oxodapagliflozin(16) exhibited in vitro(IC50=1.0nmol/L against hSGLT2 for compound 16 vs. 1.3 nmol/L for compound 1) and in vivo activities comparable to those of dapagliflozin(1). The bioactivities of 3-oxodapagliflozin (16) warrant its further evaluation as a promising SGLT2 inhibitor for the treatment of type 2 diabetes. 相似文献
66.
Dr. Jun-Dong Yi Dr. Ruikuan Xie Prof. Zai-Lai Xie Prof. Guo-Liang Chai Prof. Tian-Fu Liu Prof. Rui-Ping Chen Prof. Yuan-Biao Huang Prof. Rong Cao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(52):23849-23856
It is still a great challenge to achieve high selectivity of CH4 in CO2 electroreduction reactions (CO2RR) because of the similar reduction potentials of possible products and the sluggish kinetics for CO2 activation. Stabilizing key reaction intermediates by single type of active sites supported on porous conductive material is crucial to achieve high selectivity for single product such as CH4. Here, Cu2O(111) quantum dots with an average size of 3.5 nm are in situ synthesized on a porous conductive copper-based metal–organic framework (CuHHTP), exhibiting high selectivity of 73 % towards CH4 with partial current density of 10.8 mA cm−2 at −1.4 V vs. RHE (reversible hydrogen electrode) in CO2RR. Operando infrared spectroscopy and DFT calculations reveal that the key intermediates (such as *CH2O and *OCH3) involved in the pathway of CH4 formation are stabilized by the single active Cu2O(111) and hydrogen bonding, thus generating CH4 instead of CO. 相似文献
67.
Mei-Ling Tan Dr. Qing-Hui Guo Dr. Xue-Yuan Wang Tan-Hao Shi Dr. Qian Zhang Sheng-Kai Hou Prof. Dr. Shuo Tong Prof. Dr. Jingsong You Prof. Dr. Mei-Xiang Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(52):23857-23866
Despite the aesthetically appealing structures and tantalizing physical and chemical properties, zigzag hydrocarbon belts and their heteroatom-embedded analogues remain challenging synthetic targets. We report herein the synthesis of diverse O/N-doped zigzag hydrocarbon belts based on selective bridging of the fjords of resorcin[4]arene derivatives through intramolecular SNAr and palladium-catalyzed intermolecular C−N bond formation reactions. Preorganized conformations of mono-macrocyclic, half-belt and quasi-belt compounds were revealed to facilitate cyclization reactions to construct heteroatom-linked octahydrobelt[8]arenes. The acquired products had strained square-prism-shaped belt structures in which all six-membered heterocyclic rings adopted an unusual boat conformation with equatorially configured alkyl groups. The unprecedented heteroatom-bearing belts also exhibited different photophysical and redox properties to those of octahydrobelt[8]arene analogues. 相似文献
68.
Dr. Liqin Zhang Prof. Dr. Sai Wang Dr. Zunyi Yang Dr. Shuichi Hoshika Sitao Xie Jin Li Dr. Xigao Chen Dr. Shuo Wan Dr. Long Li Prof. Dr. Steven A. Benner Prof. Dr. Weihong Tan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(2):673-678
Expanding the number of nucleotides in DNA increases the information density of functional DNA molecules, creating nanoassemblies that cannot be invaded by natural DNA/RNA in complex biological systems. Here, we show how six-letter GACTZP DNA contributes this property in two parts of a nanoassembly: 1) in an aptamer evolved from a six-letter DNA library to selectively bind liver cancer cells; and 2) in a six-letter self-assembling GACTZP nanotrain that carries the drug doxorubicin. The aptamer-nanotrain assembly, charged with doxorubicin, selectively kills liver cancer cells in culture, as the selectivity of the aptamer binding directs doxorubicin into the aptamer-targeted cells. The assembly does not kill untransformed cells that the aptamer does not bind. This architecture, built with an expanded genetic alphabet, is reminiscent of antibodies conjugated to drugs, which presumably act by this mechanism as well, but with the antibody replaced by an aptamer. 相似文献
69.
Due to their special polar structure, amphiphilic molecules are simple to process, low in cost and excellent in material properties. Thus, they can be widely applied in the preparation of functional film materials and bionics related to cell membranes. Therefore, amphiphilic organic semiconductor materials are receiving increasing attention in research and industrial fields. The structure of organic amphiphilic semiconductor molecules usually consists of three functional parts: a hydrophilic group, a hydrophobic group, and a linking group between them. The adjustment of their correlation to achieve the target performance is particularly important and needs experimental discussion regarding synthetic methodologies. In this work, we focused on the engineering of a substituent alkyl-chain, and an amphiphilic functional molecule (benzo[b]benzo[4, 5] thieno[2, 3-d]thiophene, named CnPA-BTBT, n = 3–11) was proposed and synthesized. This molecule links the hydrophobic semiconductor backbone and hydrophilic polar group through alkyl chains of different lengths. Fundamental properties were investigated by nuclear magnetic resonance (NMR) and ultraviolet-visible spectroscopy (UV-Vis) to conform the structure and the band gap properties of the designed organic semiconductor. Thermodynamic features were investigated by thermogravimetric analysis (TGA) and corresponding differential thermal gravity (DTG), which indicate that the functional molecule CnPA-BTBT (n = 3–11) has a great stability in ambient conditions. Moreover, the results show that the binding ability of the amphiphilic molecule to water molecules was regulated by the odd-even alternating effect of the alkyl chain and the intramolecular coupling with BTBT. Furthermore, differential scanning calorimetry (DSC) and polarized optical microscopy (POM) were used to study the material properties in detail. As the length of the alkyl chain increased, the functional molecule CnPA-BTBT (n = 3–11) gradually changed from "hard" species with no thermodynamic changes to a transition one with a pair of thermodynamic peaks, and eventually to a "soft" one as a typical liquid crystal with clear observation of Maltese-cross spherulites. The cooling and freezing points were further studied, and the values and trends of their enthalpy and corresponding temperature fluctuated and alternated due to the volume effect, odd-even alternating effect, flexibility, and other functions of the alkyl chain. Three molecular models were proposed according to the thermodynamic study results, namely the brick-like model, transition model, and liquid crystal model. This work presents in-depth discussion on material structure and corresponding thermodynamic properties, and it is an experimental basis for the design, synthesis, optimization, and screening of target performance materials. 相似文献
70.
Zhennan Wu Qiaofeng Yao Osburg Jin Huang Chai Nan Ding Wen Xu Shuangquan Zang Jianping Xie 《Angewandte Chemie (International ed. in English)》2020,59(25):9934-9939
Aggregation‐induced emission (AIE) provides an efficient strategy to synthesize highly luminescent metal nanoclusters (NCs), however, rational control of emission energy and intensity of metal NCs is still challenging. This communication reveals the impact of surface AuI‐thiolate motifs on the AIE properties of Au NCs, by employing a series of water‐soluble glutathione (GSH)‐coordinated Au complexes and NCs as a model ([Au10SR10], [Au15SR13], [Au18SR14], and [Au25SR18]?, SR=thiolate ligand). Spectroscopic investigations show that the emission wavelength of Au NCs is adjustable from visible to the near‐infrared II (NIR‐II) region by controlling the length of the AuI‐SR motifs on the NC surface. Decreasing the length of AuI‐SR motifs also changes the origin of cluster luminescence from AIE‐type phosphorescence to Au0‐core‐dictated fluorescence. This effect becomes more prominent when the degree of aggregation of Au NCs increases in solution. 相似文献