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81.
Xiang Pu Hanguang Wang Ping Zou Guangtu Wang Guizhou Yue Kuan Liu Li Cheng Juhua Feng Huixian Zhang Qianming Huang Hanbing Rao 《大学化学》1986,36(1):2002053-0
The crop science of Sichuan Agricultural University is an authorized first-class discipline. As the strategic supporting department for innovative talent cultivation in agriculture and forestry major, we are facing a long-term challenge in reforming the teaching mode for basic course-organic chemistry and cultivating talented students with solid basic knowledge and strong sense of innovation. Herein a thorough survey was performing to establish the executable teaching programs for this course during the "Double-First Class Universities Plan" period. A multidimensional teaching resource library for organic chemistry course was also constructed. The new classroom teaching mode "Interest cultivation-Creative thought development-Autonomous and Cooperative learning", along with a stepwise practice teaching mode "Foundation skills-Integrated application-Innovative trial" was proposed and practiced among thirty-five majors including agriculture, forestry and veterinary, to improve the quality for innovative talent cultivation and support our first-class discipline construction. This research could probably serve as a reference for congeneric agricultural university. 相似文献
82.
Zhao L Zhu G Zhang D Di Y Chen Y Terasaki O Qiu S 《The journal of physical chemistry. B》2005,109(2):764-768
Using 1,2-bis(trimethoxysilyl)ethane as organosiloxane precursor and a triblock copolymer surfactant, Pluronic F127, as template, a highly ordered mesoporous organosilica with large cagelike pores has been successfully synthesized. Its structure was resolved to be 3-D cubic Fmm by high-resolution transmission electron microscopy. The intergrowth of hexagonal close-packed and cubic close-packed phases was observed in this material. The effect of different siliceous precursors on the mesostructure was also investigated. 相似文献
83.
84.
Xueliang Zhu Xiangyang Qi Jing Wang Jingnian Yue Zhida Sun Wenjun Lei 《Chromatographia》2007,65(9-10):625-628
A rapid method based on matrix solid-phase dispersion (MSPD) was developed for the determination of procymidone, pentachloroaniline and methyl-pentachloro-phenylsulfide in wine. After the optimisation of different parameters such as the type of adsorbent, the extraction solvent, and the extraction assistance by sonication. The analysis of samples was accomplished using gas chromatography with electron-capture detector (GC-ECD). Spiked blank samples were used as standards to counteract the matrix effect observed in the chromatographic determination. The recovery of the method was in the range 82.4–93.7% and a good linear relationship (R 2 ≥ 0.9992) with relative standard deviations lower than 8%. The limits of detection (LOD) ranged from 0.1 to 0.4 μg L?1. The proposed method was applied to the analysis of these compounds in commercial wine samples. 相似文献
85.
Yue Ming Zhou Jian Hua Ding Xie Zhang Huan Wen Chen 《中国化学快报》2007,18(1):115-117
Extractive electrospray ionization source(EESI)was adapted for ion-ion reaction,which was demonstrated by using a linear quadrupole ion trap mass spectrometer for the first ion-ion reaction of biopolymers in the atmospheric pressure ambient. 相似文献
86.
87.
The hydrogen abstraction reaction of O(^3P) with Si2H6 has been studied theoretially. Two transition states of ^3A″ and ^3A′ symmetries have been located for this abstraction reaction. Geometries have been optimized at the UMP2 leve with 6-311G (d) basis set. G3MP2 has been used for the final single-point energy calculation. The rate constants have been calculated over a wide temperature range of 200-3000K using canonical variational transition-state sheory (CVT) with small curvature tunneling effect(SCT). The calculated CVT/SCT rate constants match well with the experimental value. 相似文献
88.
Ying Wang Sheng‐Ping Yang Jian‐Min Yue Sharon Chow William Kitching 《Helvetica chimica acta》2003,86(7):2424-2433
Four novel sesquiterpenes, namely 7α,8β,13‐trihydroxy‐5,13‐marasmanolide ( 2 ), isoplorantinone ( 5 ), 4,8,14‐trihydroxyilludala‐2,6,8‐triene ( 6 ), and 8‐hydroxy‐8,9‐secolactara‐1,6‐dien‐5,13‐olide ( 10 ), together with six known ones, 7α,8β‐dihydroxy‐5,13‐marasmanolide ( 1) , 7α,8α‐dihydroxy‐5,13‐marasmanolide ( 3 ), isolactarorufin ( 4 ), blennin A ( 7 ), blennin D ( 8 ), and lactarorufin ( 9 ), were isolated from the ethanolic extract of Lactarius piperatus. The structures of these sesquiterpenes, representing diversified structural types, were determined mainly by spectroscopic methods, especially 2D‐NMR techniques. The structure of 6 was further confirmed by a single‐crystal X‐ray‐diffraction determination. 相似文献
89.
90.
A capillary zone electrophoretic method has been developed for the quantitative analysis of five phenolic glucosides, 6′-O-vanilloylarbutin (VA), 7-O-feruloylorientin (FE), lutonarin (LN), isoorient (IO) and luteolin (LL), in Gentiana piasezkii with UV detection at 270 nm. 7-O-β-D-glucosyl-coumarin was selected as the internal standard. The applied voltage was 15 kV and the capillary temperature was kept constant at 25 °C. The effect of pH, the concentration of methanol and boric acid on migration were studied systematically. Optimum separation was achieved with 200 mM boric acid buffer at pH 9.50 containing 10% (v/v) methanol. Regression equations revealed good linear relationship between the peak area ratio of each compound and internal standard and its concentration. The correlation coefficients were 0.9975, 0.9997, 0.9998, 0.9998 and 0.9988 for VA, FE, LN, IO and LL, respectively. The relative standard deviations of migration time and the peak area ratio of each analyte and internal standard were <1.78% and 4.93%, respectively. The contents of the five compounds in Gentiana piasezkii were successfully determined with satisfactory repeatability and recovery. 相似文献