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861.
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Jian‐lin Wu Jie Liu Zongwei Cai 《Rapid communications in mass spectrometry : RCM》2010,24(13):1828-1834
Triclosan is a widely used broad‐spectrum antibacterial agent that acts by specifically inhibiting enoyl–acyl carrier protein reductase. An in vitro metabolic study of triclosan was performed by using Sprague‐Dawley (SD) rat liver S9 and microsome, while the in vivo metabolism was investigated on SD rats. Twelve metabolites were identified by using in‐source fragmentation from high‐performance liquid chromatography/negative atmospheric pressure chemical ionization ion trap mass spectrometry (HPLC/APCI‐ITMS) analysis. Compared to electrospray ionization mass spectrometry (ESI‐MS) and tandem mass spectrometry (MS/MS) that gave little fragmentation for triclosan and its metabolites, the in‐source fragmentation under APCI provided intensive fragmentations for the structural identifications. The in vitro metabolic rate of triclosan was quantitatively determined by using HPLC/ESI‐ITMS with the monitoring of the selected triclosan molecular ion. The metabolism results indicated that glucuronidation and sulfonation were the major pathways of phase II metabolism and the hydroxylated products were the major phase I metabolites. Moreover, glucose, mercapturic acid and cysteine conjugates of triclosan were also observed in the urine samples of rats orally administrated with triclosan. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
864.
Jianjun Jiao Shaohong Cai Lansun Chen 《Journal of Applied Mathematics and Computing》2011,35(1-2):483-495
In this work, a biological management model with impulsive stocking juvenile predators and continuous harvesting adult predators is investigated. By the stroboscopic map of the discrete dynamical system, the prey-extinction periodic solution of the investigated system is proved to be globally asymptotically stable. By the theory of impulsive differential equation, the investigated system is also proved to be permanent. Finally, the numerical analysis is inserted to illustrate the results. Our conclusions provide reliable tactical basis for the practical biological management. 相似文献
865.
Indole is an important heterocycle substance which could be used to produce indigo dye, perfume, forage additive and tryptophan[1~3]. Although there are some methods to produce indole[4], one of the most promising routes, from an industrial point of view, seems to be the direct synthesis from aniline and ethylene glycol[5]. This is a one step reaction from reactants to indole and the starting materials are inexpensive. 相似文献
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867.
介绍了研究分子反应动力学的两大主要实验方法之一的气室法、在研究有热原子参与的反应所取得的新进展,讲述了此方法“新用”的理论依据及相应的实验条件,至此,可以获得对分子反应动力学更精细的信息,例如,态-态分辨的微分反应截面,并对两大方法进行了“现代”对比。还对两方法的发展前景作了适度的分析。 相似文献
868.
869.
Yan-zheng Bai Ze-bing Zhou Hai-bo Tu Shu-chao Wu Lin Cai Li Liu Jun Luo 《Frontiers of Physics in China》2009,4(2):205-208
Low noise position measurement is fundamental for space inertial sensors, and at present the capacitive position sensor is
widely employed for space inertial sensors. The design for the possible suppression of the front-end electric noises for a
capacitive sensor is presented. A prototype capacitive sensor with 2×10−6pF/Hz1/2 at frequency above 0.04 Hz is achieved and further improvements are discussed.
相似文献
870.