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81.
The herbicidal activities of a series of 1,2,4-triazolo[1,5-a]pyrimidine-2-sulfonanilides containing various substituents on the benzene ring were quantitatively analyzed with physicochemi-cal parameters by using Hansch-Fujita method.Variations in the activity were parabolically related to electronic parameters with the optimum pKavalue being about 6.93.The hydrophobic factor in addition to the electronic property seemed to have important effect on the activity. 相似文献
82.
Huan Huan Zhang Ya Ting Liu Rong Wang Xiao Yan Yu Xiong Wei Qu Qing Xin Zhang 《中国化学快报》2011,22(4):485-488
A novel nanodiamond-epoxy derivative(ND-EP) was synthesized by grafting epoxy monomers onto the surface of nanodiamond(ND),and characterized by FTIR and TGA.The ratio of grafted epoxy groups was determined to be 32.5 wt% by TGA.The developed methodology provides an efficient method for the functionalization of nanodiamond material,which enables a variety of advanced engineering and biomedical applications of ND. 相似文献
83.
Hua Ping Zhu Ting Ting Liu Bing Liu Hui Ling Yin Xiao Long Li Li Wang Shuo Wang 《中国化学快报》2010,21(9):1049-1052
<正>Two haptens of 3-[(5-amino-furan-2-ylmethylene)amino]oxazolidin-5-one(FZ-NH_2) and 3-{[(4-carboxyphenyl)methylene]-amino} -2-oxazolidinone(CPAOZ) were synthesized.For FZ-NH_2,immunogens were prepared by glutaraldehyde and diazo salt methods.For CPAOZ,immunogens were connected by the methods of the active ester and mixed acid anhydride.Compared with the combination,indirect competitive enzyme-linked immunosorbent assay(ic-ELISA) was developed with coating antigen of FZ-NH_2 -OVA via the glutaraldehyde method and immunogen of CPAOZ-KLH via active ester method.For furazolidone and its metabolite AOZ(NPAOZ as derivative),the sensitivities(IC_(50)) were 2.0μg/L and 2.5μg/L,limits of detection(IC_(15)) were 0.09μg/L and 0.25μg/L,respectively.A sensitive method was developed for the simultaneous determination of furazolidone in feed and its metabolite AOZ in tissue. 相似文献
84.
本文合成了正电子发射断层显像剂[18F]FET的两个新型前体:N-叔丁氧羰基-O-(2-三氟甲磺酰氧乙基)-L-酪氨酸甲酯9a和N-叔丁氧羰基-O-(2-三氟甲磺酰氧乙基)-L-酪氨酸叔丁酯9b. 化合物9a或9b以L-酪氨酸为原料, 先与甲醇发生酯化反应或与乙酸叔丁酯进行酯交换, 再用叔丁氧羰基保护氨基, 接着在苯环的酚羟基上引入羟乙基, 最后与三氟甲磺酸酐反应形成目标化合物, 这四步反应总收率分别是30%或15%. 相似文献
85.
本文利用同位素取代法考察了离子液体催化苯与烯烃烷基化反应机理.首先进行了Et3NHCl-AlCl3催化氘代苯与1-十二烯烃的反应,通过GC-MS及NMR分析产物结构,根据分析结果,在反应过程中一个D原子从苯环转移到侧链的1-碳.由此推断离子液体催化苯与长链烯烃的烷基化反应机理为:反应由Lewis酸AlCl3引发;AlCl3吸引1-十二烯烃的π电子向1-碳转移,形成碳正离子;碳正离子进一步与苯反应形成不稳定的σ络合物,σ络合物苯环上的sp3杂化碳相连的D+转移到侧链的负电1-C上取代AlCl3,生成产物2-十二烷基苯. 相似文献
86.
FAN Zhi GUO MinJie DONG Bin DIAO ChunHua JING ZuoLiang & CHEN Xin College of Sciences Tianjin University of Science Technology Tianjin China 《中国科学:化学》2010,(5)
The mono-modified β-cyclodextrin derivative,6-O-(4-aminobenzoyl)-β-cyclodextrin(1) ,was synthesized and characterized. We compared its self-assembling behavior with structurally related β-cyclodextrin derivative,6-O-(4-hydroxybenzoyl)-βcyclodextrin(2) ,in aqueous solution and in the solid state using NMR spectroscopy and single crystal X-ray structure analysis. The two complexes displayed different self-assembling behaviors.Complex 1 formed a head-to-tail helical columnar superstructure in which the substit... 相似文献
87.
The enantiomers of thirty-nine O-ethyl O-phenyl N-isopropyl phosphoroamidothioates have been separated by high performance liquid chromatography on a Pirkle model chiral stationary phase using ten mobile phase. Chromatographic data are presented for the separation of these organic phosphorus enantiomers on the chiral phase. The influences of molecular structures and compositions of mobile phases have been described. 相似文献
88.
89.
90.
<正>Accurate measurement of the optical properties of biological tissue is very important for optical diagnosis and therapeutics.An artificial neural network(ANN)-based inverse reconstruction method is introduced to determine the optical properties of turbid media,which is based on the reflectance(R) and transmittance (T) of a thin sample measured by a double-integrating-spheres system.The accuracy and robustness of the method has been validated,and the results show that the root mean square errors(RMSEs) of the absorption coefficientμ_a and scattering coefficientμ'_s reconstruction are less than 0.01 cm~(-1) and 0.02 cm~(-1),respectively.The algorithm is not only very accurate in the case of a lower albedo(~0.33),but also very robust to the noise of R and T especially for theμ'_s reconstruction. 相似文献