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151.
CHEN Guo-jun XUE Peng-chong LU Ran SONG Dong-po BAO Chun-yan XU Ting-hua ZHAO Ying-ying College of Chemistry Jilin University Changchun P. R. China 《高等学校化学研究》2009,25(2)
Four coumarin derivatives(4a―4d) with different alkoxy chains were synthesized. It was found that compound 4d showed a better gelation ability than the other compounds, for example, it could self-assemble into organogels in various organic fluids via ultrasound treatment or heating-cooling process, whereas compound 4c could only gel in a few mixed solvents and compounds 4a, 4b could not form organogel. The results from fluorescent and FT-IR spectra indicate that π-π interaction had an effect on the formatio... 相似文献
152.
Films obtained via drying a polymeric latex dispersion are normally colloidal crystalline where latex particles are packed into a face centered cubic (fcc) structure.Different from conventional atomic crystallites or hard sphere colloidal crystallites,the crystalline structure of these films is normally deformable due to the low glass transition temperature of the latex particles.Upon tensile deformation,depending on the drawing direction with respect to the normal of specific crystallographic plane,one ... 相似文献
153.
ZHU Xiao-liang ZHANG Shu-ling REN Dian-fu GUAN Shao-wei WANG Gui-bin JIANG Zhen-hua College of Chemistry Jilin University Changchun P. R. China 《高等学校化学研究》2009,25(2)
1 Introduction High performance polymers have received con-siderable attention over the past decade owing to their increased demands as replacements for metals or 相似文献
154.
QIAN Ying YU Yong-sen LI Qiu-shun WU Si-zhu ZHAO Kai-jun YANG Bai-liang ZHANG Yu-shu . State Key Laboratory on Integrated Optoelectronics College of Electronic Science Engineering . College of Chemistry Jilin University Changchun P. R. China . Electrical Diagnosis Division China-Japan Union Hospital Changchun 《高等学校化学研究》2009,25(5):624-627
A high sensitive long period fiber grating(LPFG) sensor for the detection of nitrite is proposed, which is realized by coating multiple poly(sodium 4-styrensulfonate)(PSS) and poly(diallyldimethylammonium) chloride (PDDA) layers on the fiber grating surface. The sensitivity of this LPFG sensor is maximum when the number of assembled layers is 70. Under this condition, a nitrite concentration of 3×10-3 mol/L, which is lower than the National Food Additive Standard, 4.2×10-3 mol/L, can be distinguished. The s... 相似文献
155.
ZHAO Xi LI Bin XU Shan-sheng SONG Hai-bin WANG Bai-quan State Key Laboratory of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin P. R. China 《高等学校化学研究》2009,(5)
η5-Pentamethylcyclopentadienyl-(η5-exo-tricyclo[5.2.1.02,6]deca-2,5,8-trien-6-yl) iron(3) was synthesized and characterized by 1H NMR, 13C NMR, MS, elemental analysis, IR, UV and X-ray diffraction analysis. Compound 3 was polymerized with ring-opening metathesis polymerization(ROMP) initiator (PCy3)2Cl2Ru=CHPh. 1H NMR and IR spectra revealed the presence of CH=CH units in the polymer and supported the ROMP mechanism. GPC analysis of the polymer showed that the weight-average molecular weights(Mw) was 5967, ... 相似文献
156.
YANG Xue-ying TAO Jin ZHENG Liang-yu WANG Rui-jian ZHAO Ke CAO Shu-gui Key Laboratory for Molecular Enzymology Engineering Ministry of Education Jilin University Changchun P. R. China 《高等学校化学研究》2009,25(5):690-694
Acetyl-CoA carboxylase(ACCase) is a crucial enzyme in fatty acid synthesis, by regulating the first committed step in the process. Therefore, it is a potential target for the development of new compounds against obesity or as herbicides. The cDNA encoding yeast ACCase CT domains(YCTs) from Saccharomyces cerevisiae was amplified by RT-PCR and inserted into the vector PET28a(+) for bacterial expression of YCT fused to N-terminal His-tag(YCT-his6). YCTs-his6 was expressed in Escherichia coli BL21(DE3) PLys as ... 相似文献
157.
SANG Shi-hua ZHANG Zhen-lei LI Ming College of Materials Chemistry & Chemical Engineering Chengdu University of Technology Chengdu P. R. China 《高等学校化学研究》2009,25(5)
Metastable equilibrium solubilities and densities of quaternary system Li2SO4+Li2CO3+ Li2B4O7+H2O at 288 K were determined by isothermal evaporation method. According to the experimental data, the metastable equilibrium phase diagram was plotted. The metastable phase diagram had one invariant point F, three double saturated liquid curves E1F, E2F and E3F, and three crystallization fields corresponding to Li2SO4·H2O, Li2CO3 and LiBO2·8H2O. It was found that lithium sulphate(Li2SO4) had the highest concentrat... 相似文献
158.
HSU Shaw Ling 《中国科学B辑(英文版)》2009,(1)
The metal atom net charge correlation(MANCC) method was developed in prediction of catalyst activity of asymmetric late-transition metal complexes,2-quinoxalinyl-6-iminopyridine Ni(Ⅱ),2-imino-1,10-phenanthroline Co(Ⅱ) and 2-methoxycarbonyl-6-iminopyridine Pd(Ⅱ) complexes,from the net charge of the metal atom for ethylene polymerization.Dreiding force field was modified according to the X-ray diffraction data.We found that the asymmetric structure of the complexes resulted in a charge differ-ence between two... 相似文献
159.
ZENG Xi WU Chong DONG Lei MU Lan XUE SaiFeng & TAO Zhu College of Chemistry Chemical Engineering Guizhou University Guiyang China Key Laboratory of Macrocyclic Supramolecular Chemistry of Guizhou Province Guiyang 《中国科学B辑(英文版)》2009,(4)
A new tripodal rhodamine B derivative 2 was designed and synthesized by tripodal trialdehyde and rhodamine B hydrazide for the first time. This derivative could be used as a fluorescent chemosensor for the selective and sensitive determination of copper(II) in Tris-HCl buffer and ethanol aqueous mixed media. Under the optimum conditions described herein,fluorescence enhancement at 557/577 nm was linearly related to the concentration of copper(II) in the range of 0.10 to 10.00×10-5 mol·L-1,with a corre-latio... 相似文献
160.
SHEN Yi ZHU Hua HUANG Rong ZHAO Li & YAN ShaNing Faculty of Material Science Chemical Engineering China University of Geosciences Wuhan China Faculty of Materials Science Engineering Hubei University Wuhan 《中国科学B辑(英文版)》2009,(5)
Tungsten trioxide powder with the novel morphology was prepared via the hydrothermal method with oxalic acid as the organic inducer, the structure and shape of which were detected by X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET. Furthermore, photochromic properties of the as-prepared powder samples were tested by an ultraviolet-visible spectrophotometer combined with a color difference meter. The corresponding results indicated that the induced product was still hexagonal WO3, made up... 相似文献