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121.
NewApplicationofbondFunctionBasisSets──abinitioCalculationsofNonlinearOpticalPropertiesofCh_(4-n)F_n(n=1,2,3)LiZhi-ru,TAOFu-mi...  相似文献   
122.
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   
123.
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   
124.
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   
125.
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   
126.
1 INTRODUCTION Quantitative structure-activity relationship (QSAR)is one of the necessary methods that could be emp- loyed to evaluate the hazards of organic chemicals. QSAR equation could be applied to predict the biological activity of unknown compounds, espe- cially for initial screening and evaluation of toxic compounds[1]. Moreover, the quantitative relation- ship between molecular structure and chromatogra- phic retention (capacity factor lgKW) could also bedeveloped to explain …  相似文献   
127.
1 INTRODUCTION Schiff base complexes containing sulfur and com- plexes of amino acid Schiff bases[1~5] have recently aroused increasing interest because of their antiviral, anticancer and antibacterial activities. Taurine, an amino acid containing sulfur, is indispensable to human beings and has important physiological func- tions. Recently, we have found that the Shiff base derived from taurine has manifold coordination modes[4~10]. Aromatic-ring stacking interaction is an important …  相似文献   
128.
聚甲醛/蒙脱土纳米复合材料非等温结晶动力学研究   总被引:3,自引:0,他引:3  
聚甲醛/蒙脱土纳米复合材料非等温结晶动力学研究  相似文献   
129.
1 INTRODUCTION Since the discovery of pharmacological effectsof 1,4-dihydropyridine (1,4-DHPs) as calcium mo-dulators[1], a great deal of work has been directedtowards the synthesis of 1,4-DHPs acting as cal-cium antagonists[2]. The chemical modifications onthe DHP ring, such as the introduction of differentsubstituents on heteroatoms[3], have allowed theexpansion of researches on structure-activity rela-tionship to have new insight into the molecularinteractions at the receptor l…  相似文献   
130.
1INTRODUCTIONHydrazoneshavebeenattractingmuchatten-tionfromchemistsinrecentyearsbecauseoftheirbiologicalactivities,chemicalandindustrialversa-tility,andstrongtendencytochelatetotransitionmetals[1,2],lanthanidemetals[3]andmaingroupmetals[4,5].Inthehydrazonecomplexes,thehydra-zoneligandcanactasaneutralormononegativebidentateligand,orevenasadianionictridentateliganddependingonthedonoratomsoftheligandsandthereactionconditions.Ontheotherhand,variouscompoundsderivedfromphenoxyaceticacidareveryus…  相似文献   
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