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271.
Dr. Chen Xue Shu Wang Prof. Dr. Wen-Long Liu Prof. Dr. Xiao-Ming Ren 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(20):5280-5287
A direct band gap 2D corrugated layer lead chloride hybrid, [(CH3)4N]4Pb3Cl10 ( 1 ), shows analogous topology to the {Mg3F104−}∞ layer in Cs4Mg3F10, and with the (CH3)4N+ cations locating in the inorganic layer voids and between the interlayers. Two reversible structural phase transitions occur in 1 at 225/210 K and 328/325 K upon heating/cooling, respectively. On going from the low- to intermediate-temperature phase, the space group changes from P21/c to Cmca, and the crystallographic axis perpendicular to the layers is doubled with the order–disorder transformation of (CH3)4N + cations between the interlayers. The intermediate- and high-temperature phases are isomorphic with similar cell parameters and packing structure; their main difference concerns the disorder degree of the (CH3)4N + cations between the interlayers. The two-step structural phase transitions lead to dielectric anomalies around the corresponding Tc. Interestingly, 1 shows multiband emission, originating from the recombination of exciton and emission of defects. Moreover, 1 exhibits divergent thermochromic luminescent features around the Tc on the intermediate to low temperature transition. 相似文献
272.
Peng Lu Yue Xing Zhifeng Xue Zhe Ma Bing Zhang Hui Peng Qi Zhou Hongfei Liu Zhidong Liu Jiawei Li 《Biomedical chromatography : BMC》2019,33(8)
A sensitive and accurate LC–MS/MS method was established for quantifying salvianolic acid B (Sal B), rosmarinic acid (Ros A) and Danshensu (DA) in rat plasma. Salvia miltiorrhiza polyphenolic acid (SMPA), active water‐soluble ingredients isolated and purified from Salvia miltiorrhiza Bge included Sal B, Ros A and DA. The pharmacokinetic analysis of Sal B, Ros A and DA after pulmonary administration of SMPA solution to rat was performed by LC–MS/MS. Results from the pharmacokinetic studies showed that the peak concentration of DA was 21.85 ± 6.43 and 65.39 ± 3.83 ng/mL after pulmonary and intravenous administration, respectively. DA was not detected at 2 h after administration. The absolute bioavailabilities of Sal B and Ros A were respectively 50.37 ± 27.04 and 89.63 ± 12.16% after pulmonary administration of 10 mg/kg SMPA solution in rats. The absolute bioavailability of Sal B increased at least 10‐fold after pulmonary administration, compared with oral administration. It was concluded that the newly established LC–MS/MS method was suitable for describing the pharmacokinetic characteristics of Sal B, Ros A and DA in rat after pulmonary administration of SMPA solution. The data from this study will provide a preclinical insight into the feasibility of pulmonary administration of SMPA. 相似文献
273.
Jinjuan Xue Chengjuan Huang Yuqing Zong Jiandong Gu Mingxin Wang Shuaishuai Ma 《应用有机金属化学》2019,33(11)
Fe (III)‐grafted Bi2MoO6 nanoplates (Fe (III)/BMO) with varying small quantity of Fe (III) clusters modification were fabricated through a simple hydrothermal and impregnation process. The characterization results indicate that the modification of Fe (III) clusters on the surface of Bi2MoO6 nanoplates with intimate interfacial contact is beneficial to the expansion of visible light absorption range and the separation of photoinduced carriers during the interface charge transfer process. The photocatalytic properties of the samples were studied by degradation of tetracycline (TC) and selective aerobic oxidation of biomass‐derived chemical 5‐hydroxymethylfuraldehyde (HMF) under visible light. The 1.5 wt% Fe (III) clusters‐grafted Bi2MoO6 nanoplates exhibited optimum photocatalytic activity, which is the TC degradation kinetic rate constant is 5.3 times higher than that of bare BMO, and the highest HMF conversion of 32.62% can be obtained with a selectivity of 95.30%. Furthermore, a possible visible light photocatalysis mechanism over Fe (III)/BMO sample has been proposed. This study may supply some insight for the development of visible‐light‐driven Bi2MoO6‐based photocatalysts applicable to both environmental remediation and biomass‐derived chemical transformation. 相似文献
274.
Our group has developed a series of molecular electrocatalysts for hydrogen generation based on triazenido–metal complexes (cobalt, copper, etc.). In this paper, we first present the electrocatalytic performance of a new dinuclear silver complex, [Ag2(L)2], formed by the reaction of the triazenido ligand 1‐[(2‐carboxymethyl)benzene]‐3‐[(2‐methoxy)benzene]triazene (HL) with AgNO3. At room temperature, the silver complex shows photoluminescence at 653 nm. The electrocatalytic systems based on this silver complex can afford 106.57 and 1536.36 moles of hydrogen per mole of catalyst per hour from acetic acid at an overpotential (OP) of 991.6 mV and from a neutral aqueous buffer (pH = 7.0) at an OP of 837.6 mV, respectively. Electrochemical investigations show that both silver ion and triazenido ligand play a role in determining the catalytic activities of the electrocatalytic system. 相似文献
275.
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277.
Five novel compounds as potential phosphodiesterase type 5 (PDE‐5) inhibitors were synthesized from D‐tryptophan methyl ester via the Pictet–Spengler reaction and cyclization reaction. The structures of those compounds were confirmed by elemental analyses, IR, 1H NMR, and ESI‐MS spectra. 相似文献
278.
Qian Wang Assoc. Prof. Fuhang Song Dr. Xue Xiao Pei Huang Assoc. Prof. Li Li Prof. Aaron Monte Dr. Wael M. Abdel‐Mageed Dr. Jian Wang Hui Guo Dr. Wenni He Feng Xie Dr. Huanqin Dai Miaomiao Liu Dr. Caixia Chen Hao Xu Assoc. Prof. Mei Liu Dr. Andrew M. Piggott Assoc. Prof. Xueting Liu Prof. Robert J. Capon Prof. Lixin Zhang 《Angewandte Chemie (International ed. in English)》2013,52(4):1231-1234
279.
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