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981.
HuiGUO WuXinZOU QiJI JiBenMENG 《中国化学快报》2005,16(6):751-754
A series of photo active azido analogues have been synthesized and their photochromic properties have also been investigated by UV-Vis spectrum. It will be used for the rapid and reliable preparation of large amounts of stable, non-radioactive labeled DNA and RNA hybridization probes. And it is supposed to be easily detected for its photochromic properties. 相似文献
982.
溴酸钾氧化酸性品红催化光度法测定亚硝酸根 总被引:7,自引:2,他引:7
研究了在强酸介质中亚硝酸根催化溴钾氧化酸性品红的褪色反应及其动力学条件,建立了高灵敏测定痕量亚硝酸根的新催化光度法。方法灵敏度为3.7×10^-11g/cm^2亚硝酸态氮,线性范围为0.06-0.42μg/10mL,用于测定唾液及硝钾中亚硝酸根。 相似文献
983.
笼形聚偕胺肟树脂的研究—酚处理对树脂吸附贵金属性能的影响 总被引:5,自引:0,他引:5
研究了笼形聚偕胺肟树脂(CAO)和酸式(ACAO)及碱式(BCAO)树脂对于苯酚、对-氨基酚、对-硝基酚、对-甲氨基酚和对-苯二酚的吸附和吸留作用,测定了酚处理树脂的中和当量。它反映了笼形树脂吸留外来物的特性。酚处理树脂有效地吸附Ag 、AuCl4-、PtCl62-、PdCl42-和IrCl62-等贵金属离子,吸附方式似乎与溶液的pH值有关。SEM观察表明,Ag 、Au-Cl4-和IrCl62-离子在吸附过程中被还原为零价态,在树脂表面生成形态各异的结晶。 相似文献
984.
Jin Yi Xu Qian Ran Wei Yi Hua Xiao Ming Wu Qiu Juan Wang Jing Zhang 《中国化学快报》2007,18(3):251-254
A series of 2-alkylbenzimidazole derivatives 9a-n have been designed and synthesized as a novel class of non-peptide angiotensin Ⅱ AT1 receptor antagonists. The synthesized compounds were evaluated for their antagonism of angiotensin Ⅱ, induced contraction in the rabbit thoracic aortic ring and the results showed that compounds 9a, 9g and 9j exhibited potent antagonistic activity of AT1 receptor. 相似文献
985.
Hong-wu Xu Lin Pin Jin-xia Li Zhong-ning Chen Ji-gui Wu 《Transition Metal Chemistry》2007,32(6):781-783
A novel heterohexanuclear complex [Ni2Ag4(μ-dppm)4(pymt)6](SbF 6)2 · 2DMF · H2O (1), was synthesized by self-assembly with [Ag2(μ-dppm)2(MeCN)2](SbF6) 2 and [Et4N][Ni(pymt)3] (dppm = bis(diphenylphosphino)methane, pymt = pyrimidine-2-thiolate) as components and characterized by IR spectra, elemental analysis,
1H-NMR spectrum, 31P-NMR spectrum and Visible-Ultraviolet spectrum. Structure of the complex was determined by X-ray analysis. 相似文献
986.
Enhancing the organic dye adsorption on porous xerogels 总被引:4,自引:0,他引:4
Zhijian Wu Ik-Sung Ahn Chang-Ha Lee Jung-Hyun Kim Yong Gun Shul Kangtaek Lee 《Colloids and surfaces. A, Physicochemical and engineering aspects》2004,240(1-3):157-164
We investigate the adsorption of four different organic dyes (i.e., methyl orange, alizarin red S, brilliant blue FCF, and phenol red) on porous xerogels. To understand the factors affecting the adsorption capacity of the xerogels, we vary the hydrophobicity and the textural properties of the xerogels as well as the solution pH. We control the hydrophobicity by mixing two different precursors (i.e., vinyltriethoxysilane (VTES) and tetraethoxysilane (TEOS)) and the textural properties by using cetyltrimethylammonium bromide (CTAB) as a templating agent. We find that the adsorption capacity is enhanced as the organic/inorganic hybrid xerogel or the templated xerogel is used instead of the purely inorganic or the untemplated xerogel. In all the cases studied, adsorption decreases as the pH is increased due to the electrostatic repulsion between the dyes and the xerogel surface. We find that both the hydrophobic surface and larger pore size/volume are required to enhance the adsorption capacity significantly. 相似文献
987.
[structure: see text] Platinum(II) terpyridyl acetylide complex (1) was incorporated into Nafion membranes as a photosensitizer, and the Nafion was immersed in an aqueous or organic solution of 7-dehydrocholesterol, alpha-pinene, or cyclopentadiene. This photosensitizer system can generate singlet oxygen ((1)O(2)) in high quantum yield to oxidize the alkenes in the solution outside the Nafion and can be easily removed from the reaction vessel at the end of the photooxidation. 相似文献
988.
碱式纤维素基磁性聚偕胺肟树脂(BMAO)吸附(NH4)2IrCl6是快速过程,属超当量吸附。吸附结果生成AO-Ir和AO2-Ir3络合物,随后Ir(Ⅳ)被偕胺肟基还原为Ir(0),聚集成球状晶簇附着在树脂表面。 相似文献
989.
Yi-Lu Sun Ren-Jang Wu Yu-Ching Huang Pi-Guey Su Murthy Chavali Yi-Zhen Chen Chu-Chieh Lin 《Talanta》2007,73(5):857-861
In situ preparation of polypyrrole (Ppy) by photo-polymerization coated on a quartz crystal microbalance (QCM) as a low humidity sensor was reported. Different concentrations of Ppy films say 0 wt.% (as blank), 0.1, 1, and 10 wt.% were investigated to measure humidity concentrations between 14.7 and 5412.5 ppmv. The adsorption/desorption behavior was also examined at humidity concentration 510.2 ppmv. The sensitivities of 0, 0.1 and 1 wt.% Ppy films at 51.5 ppmv were 0.143, 0.219 and 0.427, respectively. For 1 wt.% Ppy, the highest sensitivity was obtained. The slope and correlation coefficients (R2) for 1 wt.% Ppy at the ranges of 14.7–898.6 ppmv were 0.0646 and 0.9909, respectively. A series of molecular simulations have been carried out to calculate bond energy for the water molecule interaction with Ppy, which was found to be 3 kcal/mol indicating the existence of hydrogen bonding during the sorption process. Based on Langmuir isotherm adsorption assumption, for 0.1 and 1 wt.% Ppy films, the association constants were 2606.30 and 5792.98, respectively. This larger association constant for 1 wt.% Ppy film explains higher sensitivity. 相似文献
990.
碱处理笼形聚偕氨肟树脂(BCAO)对羧酸表现出强的吸附能力。一元羧酸在BCAO树脂上以多层吸附为主要特征。二元和三元羧酸则以单层吸附占优势。后者可能是以双阴离子的一个负极吸着在BCAO树脂表面,形成了对其他羧酸阴离子起排斥作用的负离子场。另外,双阴离子也有可能和两个氨基结合形成次级交联,妨碍着其他离子迁移和扩散。 相似文献