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101.
Xiangfei Lü Nanjiang Hu Jun Li Hongrui Ma Kai Du Ran Zhao 《Research on Chemical Intermediates》2014,40(5):1911-1922
A novel 5,15-di-[4-carboxylatomethoxy]phenyl-10,20-diphenylporphyrin, its copper complex and the corresponding metalloporphyrin-TiO2 photocatalyst were synthesized and characterized by DRS, SEM, XRD, and FT–IR. The photocatalytic effects of anataseTiO2 impregnated with this copper(II) porphyrin was investigated by photodegradation of 4-nitrophenol(4-NP) in aqueous solution under Xenon lamp irradiation. The results indicated that the photoactivity of copper(II) porphyrin-TiO2 composite was evidently enhanced by the interaction between carboxyl of the porphyrin molecule and hydroxyls anchored on the TiO2. Futhermore, the copper(II) carboxylic porphyrin displayed good adsorption behavior and activity of the dye-sensized TiO2 system. 相似文献
102.
Xu Feifan Wei Wei Zhang Chao Li Huawei Jing Peng Li Xin Wei Min Yu Danrui Zhang Yong Zhu Quanyao 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(2):697-703
Journal of Radioanalytical and Nuclear Chemistry - Controlling heat accumulation is one of the major challenges for block materials synthesizing via bulk polymerization. In the paper, cross-linked... 相似文献
103.
A quantification method for imatinib (IM), its major metabolite N-desmethyl imatinib (NDI), and a degradation by-product was developed using CE–MS combined with an online concentration technique. The use of multiple reaction monitoring (MRM)–MS/MS further improved the sensitivity of this technology. Liquid–liquid extraction (LLE) using tertiary butyl methyl ether yielded high recovery and reproducibility for the pretreatment of serum samples. The recovery rate exceeded 83% for all three analytes, and was 90% for IM. To improve quantification results, a conductivity-induced online analyte concentration technique, field-amplified sample stacking (FASS), was used. The S/N ratios were improved at least 10-fold when compared with conventional capillary zone electrophoresis. The detection limits were 0.2 ng/mL for IM, 0.4 ng/mL for NDI, and 4 ng/mL for the degradation by-product. These results are superior to those previously obtained by other reported methods. The new method was validated in terms of its selectivity, intra- and interday repeatability and accuracy, and sample storage stability, following the guidelines issued by the European Medicines Agency. Considering the convenient pretreatment procedure (LLE), superior sensitivity, and fast analysis speed (<15 min), this method can be useful in the determination of imatinib levels in blood. 相似文献
104.
Dr. Yong Wang Yajun Zhao Shuaishuai Zhu Prof. Dr. Xingping Zhou Prof. Dr. Jing Xu Prof. Dr. Xiaolin Xie Prof. Dr. Rinaldo Poli 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(15):6044-6050
A strategy that uses carbon monoxide (CO) as a molecular trigger to switch the polymerization mechanism of a cobalt Salen complex [salen=(R,R)-N,N′-bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediamine] from ring-opening copolymerization (ROCOP) of epoxides/anhydrides to organometallic mediated controlled radical polymerization (OMRP) of acrylates is described. The key phenomenon is a rapid and quantitative insertion of CO into the Co−O bond, allowing for in situ transformation of the ROCOP active species (Salen)CoIII-OR into the OMRP photoinitiator (Salen)CoIII-CO2R. The proposed mechanism, which involves CO coordination to (Salen)CoIII-OR and subsequent intramolecular rearrangement via migratory insertion has been rationalized by DFT calculations. Regulated by both CO and visible light, on-demand sequence control can be achieved for the one-pot synthesis of polyester-b-polyacrylate diblock copolymers (Đ<1.15). 相似文献
105.
Here we described the design and synthesis of a discrete 3D amphiphilic metallacage 4,in which the tetragonal prismatic frameworks act as the hydrophobic cores and the poly(ethylene glycol)(PEG)chains as the hydrophilic tails.The structure of 4 was characterized by 1H NMR,31P NMR and electrospray ionization time-of-flight mass spectrometry(ESI-TOF-MS).Notably,4 with its Iong PEG tails was subsequently ordered into micelles at a low concentration(1.20×10^-6 mol/L)in water.As the concentration and cultivation time increased,the micelles can further self-assembly into nanofibers and nanoribbons.Considering the dynamic property of the coordination bond,these structures show reversible transformation under external stimuli. 相似文献
106.
Pan Yong Qi Ronghua He Pei Shen Ruiqing Jiang Jiajia Ni Lei Jiang Juncheng Wang Qingsheng 《Journal of Thermal Analysis and Calorimetry》2020,140(5):2575-2583
Journal of Thermal Analysis and Calorimetry - Chemical reactivity hazards of organic peroxides are major concerns of the chemical industry due to many serious incidents every year. Thermal hazard... 相似文献
107.
Liu Yu Wang Yong Li Guangqiang Yuan Cheng Lu Ru Li Baokuan 《Journal of Thermal Analysis and Calorimetry》2020,139(2):923-931
Journal of Thermal Analysis and Calorimetry - The structure, vaporization behavior and crystallization of CaF2–CaO–Al2O3 slags with different SiO2 contents for electroslag remelting... 相似文献
108.
Wave-activity relation containing wave-basic flow interaction based on decomposition of general potential vorticity 下载免费PDF全文
On the basis of the general potential vorticity theorem(GPV),a new wave-activity relation is derived in an ageostrophic and nonhydrostatic dynamic framework.Whe... 相似文献
109.
就植物酸碱指示剂材料的筛选,植物色素提取液的稳定性,色素晶体的提取,色素临时提取液的变色情况测试,色素提取液测酸雨等方面进行研究,旨在学会科学研究的方法。 相似文献
110.
This review of the current status of conducting polymers will focus on recent progress which demonstrates that the initial promise of the late 1970's has become reality. Conducting polymers are now available as materials with truly unique properties: They combine the important electronic and optical properties of semiconductors and metals with the attractive mechanical properties and processing advantages of polymers. Conducting polymer blends based upon polyaniline (PANI) are a new class of materials in which the threshold for the onset of electrical conductivity (σ) can be reduced to volume fractions below 1%, well below that required for classical percolation (16% by volume for globular conducting objects dispersed in an insulating matrix in three dimensions). The origin of this remarkably low threshold for the onset of electrical conductivity is the self-assembled network morphology of the PANI polyblends which forms during the course of liquid-liquid separation. Since the average density of the conducting network near threshold is small, the conductivity increases smoothly and continuously over many orders of magnitude as the concentration of conducting polymer increases above threshold. The low percolation threshold and the continuous increase of σ(f) above threshold are particularly important; as a result of this combination, conducting polyblends can be reproducibly fabricated with controlled levels of electrical conductivity while retaining the desired mechanical properties of the matrix polymer.1-3) 相似文献