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131.
NewApplicationofbondFunctionBasisSets──abinitioCalculationsofNonlinearOpticalPropertiesofCh_(4-n)F_n(n=1,2,3)LiZhi-ru,TAOFu-mi...  相似文献   
132.
1 INTRODUCTION The complexes of amino acid Schiff base have attracted considerable attention because of their bio- activities[1, 2]. Taurine is a special amino acid in be- ings, and recently the complexes of taurine conden- sation salicylaldehyde Schiff …  相似文献   
133.
1 INTRODUCTION 5-Fluorouracil (5-FU) is an antimetabolite with good antimicrobial and antitumor activities but has toxic side effects[1~4]. In order to improve the topical delivery of 5-FU and reduce the side effects, many derivatives of 5-FU have been synthesized, some of which are of improved activity. 5-Fluorou- racil-1-acetic acid is a member of the family[5~8], which belongs to the pyrimidine base and is a cyto-toxic analogue of the natural base thymine, and has proven useful in th…  相似文献   
134.
N-(2-甲氧羰基-1-甲基)-乙基-(N′-D-乙酰基吡喃型糖)硫脲类化合物的合成及生物活性;糖基硫脲;β-氨基丁酸;合成;生物活性  相似文献   
135.
1 INTRODUCTION II-VI semiconductor materials with ZnO as the representative possess wide forbidden gaps and high exciton binding energy, which have paved the way for the study of exciton characters and short wave photo-conducting devices. They present wide appli- cations, such as ultraviolet laser transmitting device, piezoelectric device, optical waveguild and high efficient quantum dot luminous apparatus[1~8]. Re- cently, II-VI semiconductor cluster materials with nano-structure ha…  相似文献   
136.
1 INTRODUCTION Great attention has been attracted to design novel heterometallic molecular materials with phosphorus- and sulfur-containing ligands, owing to their abundant optical and opto-electronic properties[1~4]. Self-assembly is an efficient ap- proach to obtain heterometallic assembly by the Incorporation of two different metal components[5, 6]. We are interested in investigating the reaction between Pd(diimine)(dithiolate) and metal dip- hosphine Cu2(μ-dppm)2(MeCN)42 , the fo…  相似文献   
137.
A metal-organic coordination polymer [Co(phen)(BDC)(H2O)]n·0.5nH2BDC (H2BDC = terephthalic acid, phen = 1,10-phenanthroline) has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in triclinic, space group P1 with a = 9.771(3), b =10.739(3), c = 11.249(4) , α = 75.946(3), β = 65.306(3), γ = 86.073(4)o, V = 1039.6(6) 3, C24H17CoN2O7, Mr = 504.33, Dc = 1.611 g/cm3, μ(MoKα) = 0.878 mm-1, F(000) = 516, Z = 2, the final R = 0.0547 and wR = 0.1138 for 2916 observed reflections (I > 2σ(I)). It exhibits a one-dimensional zigzag chain-like structure.  相似文献   
138.
ntroductionThebasictopicsofthispaperinvolvetheChebyshevτ_methodtodiscretizeaclasoflinearboundaryvalueproblemsoftheformUxx+Uyy...  相似文献   
139.
The title compound, N-(1′-H-pyrrol-2′-ylcarbonyl)-5-amino-1,10-phenanthroline, was synthesized by the reaction of a-pyrrolyl carbonyl chloride and 5-amino-1,10-phenanthroline in pyridine. Determined by X-ray structure analysis, it crystallizes in triclinic system, space group P1 with the following crystallographic data: C20H21N5O3, Mr = 379.42, a = 7.8559(4), b = 9.1681(6), c = 14.6818(9) A, α= 73.254(10),β= 88.938(15), γ= 68.080(10)°, V= 934.66(10) A3, Z = 2, F(000) = 400, Dc = 1.348 g/cm^3 and p = 0.094 mm-1. The final R = 0.0680 and wR = 0.1419 for 2142 observed reflections with I 〉 2σ(/), and R = 0.1084 and wR = 0.1643 for all reflections. Two aromatic ring planes (pyrrole and phenanthroline rings) are connected by the amide plane. Two different types of intermolecular hydrogen bonds, O-H…N and N-H…O, exist in the crystal. The title complex molecules are connected through hydrogen bonds and weak π-π stacking interactions to generate a 3-D supramolecule.  相似文献   
140.
仉华 a  c  张炎b  李全民 a  杜新贞c 《中国化学》2009,27(3):518-522
以Cu(II)为光谱探针建立了一种高选择性、高灵敏度测定异烟肼的新方法。试验表明:在pH 6.0时,Cu(II)可被异烟肼还原生成Cu(I),反应生成的Cu(I) 与SCN-反应生成CuSCN白色乳状沉淀,在硝酸钠的存在下该沉淀可被浮选至水相表面。通过测定水相中剩余Cu(II)的量,可以间接测定异烟肼的含量。已反应Cu(II) 的量与异烟肼的浓度呈良好的线性关系,线性范围为0.050-4.50 µg mL-1,检出限为0.048 µg mL-1。该法已经成功的用于药物样品和病人尿液样品中异烟肼含量的测定。  相似文献   
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