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51.
LI Jun-Linga① GU Juna QIU Guang-Minb a 《结构化学》2006,25(5):589-593
1 INTRODUCTION Since the introduction of QSAR by Hansch and Fujita in 1964, Deutsch and Hansch have quickly used it in the study of nitrophenylamine sweet reagents. They found good correlation between their distribution coefficients in octanol/water system and sweetness degree. Subsequently, they detected that vibration of aroma-substituent compounds has so- mething to do with sweetness. Henceforth, statistic correlations between structure and sweetness ofseries compounds have been inv… 相似文献
52.
1 INTRODUCTION Since the discovery of carbon nanotubes (CNTs) by S. Iijima[1] in 1991 as a quasi-one-dimensional nano-material, extensive attention has been paid to CNTs due to their special electric conductivity, me- chanical properties and potential applications in molecular device, complex material and so on. The structures of CNTs could be described as graphite sheet with planar hexagonal network structure cur- ling into a tube having the diameter of only several nanometers. In t… 相似文献
53.
1 INTRODUCTION Late-transition metal complexes as catalysts for ethylene oligomerization and polymerization have become an intense research subject[1]. Nickel com- plexes are in hot point due to the significant achieve- ments of academic research[2, 3] and industrial appli- cations[4, 5]. The nickel complexes with bidentate [P,O] ligands were industrialized as the SHOP pro- cess for α-olefins[4]. It is supposed that late transition metal complexes have a strong propensity of under- goi… 相似文献
54.
在酸性条件下, 分别合成了四氯合钯(II)离子与2种喹诺酮(诺氟沙星, NFLX=C16H18N3O3F; 环丙沙星, CPLX=C17H18N3O3F)离子形成的配合物(NFLXH)2[PdCl4]8226;2H2O (1)和(CPLXH)2[PdCl4]8226;2H2O (2). 用元素分析、IR、UV以及摩尔电导测定等方法对其进行了表征. 配合物1的晶体结构经X射线单晶衍射确定, 结构参数: 三斜晶系, P-1空间群, a=0.84561(17) nm, b=0.94191(19) nm, c=1.2832(3) nm; α=111.26(3)°, β=97.23(3)°, g=96.38(3)°, V=0.9312(4) nm3, Z=1, 最后吻合因子R=0.040, wR=0.088. 利用紫外光谱法、荧光光谱法对配合物与小牛胸腺DNA (ct-DNA)的作用进行了研究, 研究表明, 配合物对DNA的作用模式为插入作用, 与DNA的结合常数Kb分别为: Kb(1)=2.06×104, Kb(2)=2.43×104. 其后测试了配合物对体外肿瘤细胞的抗增殖活性. 经采用四甲基偶氮唑蓝分析法(MTT法)测试后发现配合物1和2对人肺腺癌A549细胞、人原髓细胞白血病HL-60细胞的增殖抑制作用显著强于相应的喹诺酮分子本身, 其中配合物2对人肺腺癌A549细胞增殖有明显的抑制作用, 抑制率可高达(95.4±3.7)%, 半数抑制浓度(IC50, 72 h)为(124.5±10.3) μmol8226;L-1. 相似文献
55.
Wei-qiang Zhou~ 《高分子科学》2008,(1):81-90
The copolymerization of dibenzofuran(DBF)and 3-methylthiophene(MET)was successfully achieved electrochemically by direct anodic oxidation of the monomer mixtures in boron trifluoride diethyl etherate.The effects of applied polymerization potential and the monomer concentration ratios on the copolymerization were investigated by linear sweep voltammetry and cyclic voltammetry(CV).The structure of copolymer films were investigated by UV-Vis,infrared spectroscopy,thermal analysis.As-formed novel copolymers ... 相似文献
56.
通过微弧氧化法在Na3PO4+K2Cr2O7电解液中制备了系列铬掺杂二氧化钛薄膜. X射线和扫描电镜显示薄膜的主要晶相为锐钛矿型二氧化钛,且表面为多孔结构. 在可见光照射下,薄膜对降解亚甲基蓝和分解水有着较好的光催化性能,这主要是由铬的掺杂引起的.由于铬的掺杂,一方面在二氧化钛中形成了Cr3+/Cr4+离子对,另一方面在带隙中形成了氧的空位能级. 前者降低了电子-空穴的复合几率,而后者在二氧化钛的禁带中形成了新的能级. 新能级的形成使得由二氧化钛价带跃迁至氧空位能级所需的光子能量减少. 另外探讨了微弧氧化形成掺杂二氧化钛薄膜的机制. 相似文献
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58.
以磷钼酸作为催化剂,芳香醛、胺和三丁基烯丙基锡三组分在水作为溶剂,室温下高产率的得到相应的烯丙基胺。 相似文献
59.
60.
Photochemical degradation of environmentally persistent perfluorooctanoic acid (PFOA) in the presence of Fe(Ⅲ) 总被引:1,自引:0,他引:1
Yuan Wang~ 《中国化学快报》2008,19(3):371-374
Environmentally persistent and bioaccumulative perfluorooctanic acid (PFOA) was difficult to be decomposed under the irradiation of 254 nm UV light. However, in the presence of 80μmol/L Fe(Ⅲ), 80% of PFOA with initial concentration of 48μmol/L (20 mg/L) was effectively degraded and 47.8% of fluorine atoms in PFOA molecule were transformed into inorganic fluoride ion after 4 h reaction. Shorter chain perfluorocarboxylic acids bearing C3-C7 and fluoride ion were detected and identified by LC/MS and IC as the degradation products in the aqueous solution. It was proposed that complexes of PFOA with Fe(Ⅲ) initiated degradation of PFOA irradiated with 254 nm UV light. 相似文献