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241.
242.
通过分子设计,合成了一种新颖的双β-二酮有机配体9-乙基-3,6-二(乙酰基-3-苯甲酰基)咔唑(H2L)及其铕配合物,红外光谱和电子光谱表明Eu^3+与H2L发生配位。配合物的溶液荧光光谱不仅有613 nm处的中心离子Eu^3+的特征红光,属^5D0→^7F2跃迁带,还有445nm处配体的宽带蓝色发光,属H2L^*→H2L跃迁带,而配合物的光致发光光谱只有611 nm处为中心离子Eu^3+的特征红光,属^5D0→^7F2跃迁带,峰形尖锐,半峰宽仅7 nm,单色性好,表明该固体铕双β-二酮配合物是一种潜在的红色发光材料。 相似文献
243.
Weihong Ji Tianlu Zhang Zhiguo Lu Jie Shen Jing Hu Yunwei Niu Zuobing Xiao Xin Zhang 《中国化学快报》2019,30(3):747-749
Mesoporous silica nanospheres loaded with sandela 803 (S803@MS-S) are prepared for application to wallpaper. The nano-fragrance has high encapsulation efficiency and property of photo-driven release. 相似文献
244.
The nonlinear optical membrane used for image processing was prepared using tetraethyl silicate by sol-gel method under mild conditions. Ru(bpy)3Cl2 (bpy, bipyridine) was immobilized in the sol-gel matrix. This light-excitable membrane containing Ru(bpy)3Cl2 as photocatalyst could catalyze the Belousov-Zhabotinsky reaction by illumination. Our results indicated that a fine-definition image processing could be autoperformed when projecting a picture on this medium. The imaging process was an image evolution process, which was similar to that of the human vision process. 相似文献
245.
通过流动相中电解质浓度对毛细管电色谱柱效能的流动相平均线速度的影响,研究了CEC中双电层叠加现象。提出选择合适电解质组成的浓度及在制备色谱柱过程中避免细小和破碎的固定相颗粒进入柱中,以有效地减小双电层叠加作用。 相似文献
246.
Daqing Shi Liangce RongJuxian Wang Qiya ZhuangXiangshan Wang Hongwen Hu 《Tetrahedron letters》2003,44(15):3199-3201
A short and facile synthesis of a series of quinazolin-4(3H)-ones and 1,2-dihydroquinazolin-4(3H)-ones was accomplished in good yields via the novel reductive cyclization of o-nitrobenzamides and triethyl orthoformate, aldehydes or ketones promoted by TiCl4/Zn. 相似文献
247.
Song C Wang D Gu G Lin Y Yang J Chen L Fu X Hu Z 《Journal of colloid and interface science》2004,272(2):340-344
Silver-coated poly(methyl acrylic acid) (PSA) core-shell colloid particles were prepared by an in situ chemical reduction method. Crystalline silver/titania composite hollow spheres were obtained by coating the as-prepared PSA/silver particles with an amorphous titania layer and subsequently calcining in Ar atmosphere. SEM and TEM investigation indicated that the size of the as-prepared PSA/silver and PSA/silver/TiO(2) core-shell particles and silver/titania composite hollow particles was fairly uniform and the wall thickness of the hollow spheres was in the range of 40-80 nm. UV-vis absorption spectra were recorded to investigate their optical properties. 相似文献
248.
Raman spectroscopic analysis of supersaturated aqueous solution of MgO.B2O3-32%MgCl2-H2O during acidification and dilution 总被引:1,自引:0,他引:1
Zhihong L Bo G Shuni L Mancheng H Shuping X 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(13):3125-3128
Raman spectra of supersaturated aqueous solution of MgO.B2O3-32%MgCl2-H2O during acidification/alkalization and dilution have been studied. The assignments of the recorded Raman shift are given. The main existing forms of polyborate anions and their interaction in borate aqueous solution have been proposed through spectroscopic analysis. The experimental results indicate that the higher concentration of cation are beneficial not only to the dissolution of boric acid but also to the polymerization of polyborate anions. The existing forms and interaction among them also depend on the concentration of boron and the pH value in solution. 相似文献
249.
Simple and sensitive electrochemical method for the determination of metronidazole, based on a nanostructured film coated glassy carbon electrode (GCE), is described. Multi-walled carbon nanotubes (MWNT) was dispersed into water in the presence of a hydrophobic surfactant to give very stable and homogeneous MWNT suspension, and a MWNT-film coated GCE was achieved via evaporating solvent. Metronidazole yields a well-defined reduction peak whose potential is −0.71 V at the MWNT-film coated GCE in pH 9.0 Britton-Robinson buffer. Compared with bare GCE, the MWNT-film modified GCE significantly enhances the reduction peak current of metronidazole. All the experimental parameters were optimized for the determination of metronidazole. The detection limit is 6×10−9 mol/l at 2 min accumulation. This method has been successfully used to determine metronidazole in the drugs. Furthermore, results obtained by the proposed method have been compared with spectrophotometric method. 相似文献
250.
Based on gaseous compound introduction as 1-phenyl-3-methyl-4-benzoylpyrazolone[5](PMBP) chelate of aluminum by electrothermal vaporization in ICP-AES, a method for determination of trace aluminum was developed. Trace aluminum was vaporized at temperature of 1000 degrees C, and the vaporization behavior of aluminum chelate was detailedly investigated. Under the optimum conditions, the detection limit of aluminum was 0.6 ng ml(-1), and the relative standard deviation for 0.1 mug ml(-1) aluminum was 4.7% (n=8). The proposed method was applied to the determination of trace aluminum in rice flour reference materials, and the results well agreed with the reference values. 相似文献