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101.
甲基环戊二烯基水杨酸钛(Ⅳ)配合物的合成与表征 总被引:2,自引:0,他引:2
采用不相法和两相法用二氯二甲茂钛与相应的水杨酸反应合成了6个配合物:二甲基环戊二烯基水杨酸钛(I),二甲基环戊二烯基二水杨酸钛(Ⅱ),二甲基环戊二烯基-5硝基水杨酸钛(Ⅲ),二甲基环戊二烯基二5-硝基水杨酸钛(IV),二甲基环戊二烯基3,5-二硝基水杨酸钛(V),二甲基环戊二烯硫代水杨酸钛(VI),对这些化合物进行了元素分析,测定了熔点,计论了它们的红外光谱和核磁共振谱。 相似文献
102.
用媒质(Mediator)进行间接电解氧化有已许多报道与综述。该法与直接电解氧化法相比有以下优点:1.能在较低的电极电势下电解,从而既可抑制副反应;2.又可提高选择性(如媒质选择恰当);3.电流密度也可提高;4.底物在阳极不易产生树酯化;5.电流效率与化学收率高;6.媒质也可以循环再生利用等。 相似文献
103.
Gang‐yi Liu Wei Wang Jing‐ying Jia Chuan Lu Yan‐mei Liu Meng‐qi Zhang Yun Liu Shui‐jun Li Chen Yu 《Biomedical chromatography : BMC》2010,24(6):574-580
A simple, reliable and sensitive liquid chromatography tandem mass spectrometry (LC‐MS/MS) protocol was developed and validated for quantification of bisoprolol in human plasma. The sample was pretreated with a simple procedure of protein precipitation and an isotope‐labeled d5‐bisoprolol was used as internal standard. The chromatographic separation was performed on a Capcell Pak C18 MG III column (100 mm × 2.0 mm, 5 µm). The protonated ion of the analyte was detected in positive ionization by multiple reaction monitoring mode. The mass transition pairs of m/z 326.3 → 116.3 and m/z 331.3 → 121.3 were used to detect bisoprolol and the internal standard, respectively. Linearity, accuracy, precision, recovery, matrix effect, dilution test and stability were evaluated during method validation over the range of 0.5–100 ng/mL. The validated method was successfully applied to analyze human plasma samples in a bisoprolol bioavailability study. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
104.
Lin HE Xian Fu LIN* De Shui LV Zhi Chun CHEN Institute of Applied Chemistry of Zhejiang University Hangzhou 《中国化学快报》2001,(1)
Preparing the organized ultrathin film of proteins is the key to developing of protein-based molecular devices such as biosensors. In the past, the organized molecular layers were fabricated by the means of Langmuir-Blodgett (LB), which utilized the amphipathy of molecules. Molecular deposition (MD) which is based on the electrostatic interaction between the charged substrates and oppositely charged absorbate is a new and versatile method for preparing organized self-assembled ultrathin film… 相似文献
105.
Lan TAO* Ling Li ZHANG Shui Jun SHEN Xiao Ping HAN Department of Chemistry Hangzhou Teachers College Hangzhou 《中国化学快报》2001,(9)
1, 2, 4- and 1, 2, 3-triazole derivatives have found wide applications as plant growth regulators1, bactericides and medical fungicides2, insecticides3 and in dyeing and color development4.One of the general routes of synthesis of 1-aryl-1, 2, 3-triazoles was to treat aryl azides with a-keto phosphorus ylides in dry refluxing benzene for 0.5 to 2 days5. Herein we report, for the first time, a very quick and simple, microwave-promoted synthesis of 1-aryl-1, 2, 3-triazoles 3 from aryl azides 1 an… 相似文献
106.
Guan‐E Wang Gang Xu Ning‐Ning Zhang Ming‐Shui Yao Ming‐Sheng Wang Guo‐Cong Guo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(9):2718-2721
Superlattice materials offer new opportunities to modify optical and electrical properties of recently emerging 2D materials. The insertion of tetraethylbenzidine (EtDAB) into interlamination of the established 2D PbI2 semiconductor through a mild solution method yielded the first lead iodide superlattice, EtDAB?4PbI2 (EtDAB=tetraethylbenzidine), with radical and non‐radical forms. The non‐radical form has a non‐ionic structure that differs from the common ionic structures for inorganic–organic hybrid lead halides. The radical form shows five orders of magnitude greater conductance and broader photoconductive response range (UV/Vis → UV/Vis‐IR), than pure PbI2 and the non‐radical form of the superlattice. 相似文献
107.
108.
Shuliang Shui Xuyang Zhang Jingjing Li 《Nonlinear Analysis: Theory, Methods & Applications》2010,73(5):1277-1288
We use the theory of differential inclusions, Filippov transformations and some appropriate Poincaré maps to discuss the special case of two-dimensional discontinuous piecewise linear differential systems with two zones. This analysis applies to uniqueness and non-uniqueness for the initial value problem, stability of stationary points, sliding motion solutions, number of closed trajectories, existence of heteroclinic trajectories connecting two saddle points forming a heteroclinic cycle and existence of the homoclinic trajectory 相似文献
109.
Signs change of nonlinear refractive index in ZnSe is observed by employing a modified double 4f imaging system at the wavelength of 800 nm using picosecond pulses with different pulse energies. This process results from the competition of the bound electronic nonlinear refraction and the free carrier refraction. At low intensity, positive nonlinear refraction is obtained, which is attributed to bound electrons. As the increase of laser beam intensity, the nonlinear refractive index become small, and changes to negative. This is ascribed to free carriers generated by two-photon absorption. Additionally, the nonlinear refractive index of bound electron and the refractive index change of free carrier are determined unambiguously by a simple method. 相似文献
110.
有机过氧化物-芳叔胺体系引发甲基丙烯酸甲酯聚合的研究 总被引:1,自引:2,他引:1
以过氧化二酰(BPO、LPO)或有机过氧化氢物(TBH、CHP)和芳叔胺如DMA或对位具有不同取代基的衍生物组成的引发体系进行MMA聚合,研究过氧化物与胺的结构对聚合的影响。结果表明,过氧化二酰的活性要比有机过氧化氢物大,其顺序为BPO>LPO>CHP>TBH。对于BPO-芳叔胺或LPO-芳叔胺体系,芳叔胺中给电子取代基能提高聚合速度,而吸电子取代基能降低聚合速度。测定了MMA聚合的总活化能E_α,BPO-芳叔胺体系时E_α=36-54kJ/mole,LPO-芳叔胺体系时E_α=56-71kJ/mole;还研究聚合动力学。 相似文献