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161.
162.
163.
C. X. Lu Qiang Li Jingqi Pan 《Journal of polymer science. Part A, Polymer chemistry》1985,23(12):3031-3044
Four novel semirigid poly(amide-ester)s having the same ordered amide-amide-ester-ester (-AAEE-) and the same or the different phenyl structure were synthesized from the various combination of active acylamide of benzotriazole (HBT) such as 1,1′-(isophthaloyl)bisbenzotriazole (IPBBT) and 1,1′-(terephthaloyl)bisbenzotriazole (PBBT) with diols such as N,N'-bis(2-hydroxyethyl)isophthamide (HEIPA) and N,N'-bis(2-hydroxyethyl)terephthamide (HEPTA) which prepared from the selective N-acylation of IPBBT or PBBT with aminoethanol in excellent yield at room temperature. Before the preparation of diol monomers, a model reaction of selective N-acylation was also completed from active monoacylamide of benzotriazole, 1-benzoylbenzotriazole with aminoethanol. The ordered structure of poly(amideester)s were characterized by infrared (IR) and NMR spectra. On the bases of different reactivity between selective N-acylation and O-acylation of active acylamide of benzotriazole, poly(amide-ester)s having the ordered AAEE and the same phenyl structure were also readily synthesized from the IPBBT or PBBT with aminoethanol under mild conditions by one-bath process. 相似文献
164.
Qiang Li Pingfan Wu Yongge Wei Hongyou Guo 《Journal of organometallic chemistry》2006,691(6):1223-1228
An organic-inorganic hybrid compound, (Bu4N)2[Mo6O18(NAr)] (Ar = p-BrC6H4) has been synthesized via the DCC dehydrating protocol of the reaction of [α-Mo8O26]4− with 4-bromoaniline hydrochloride in anhydrous acetonitrile, which has been characterized by UV-Vis spectra, 1H NMR and single crystal X-ray diffraction study. By comparing the UV-Vis spectra, which were used to monitor the reaction, the optimum preparative condition for this compound was also determined. This compound crystallizes in the monoclinic space group P21/n, which is featured in a terminal para-bromophenylimido group linked to an Mo atom of a hexamolybdate cluster by a Mo-N triply bond. In addition, there are π-π dimerization of the neighboring cluster anions though the parallel aromatic rings in their crystals. 相似文献
165.
两个具有特殊骨架的C_(20)-二萜生物碱北乌灵(kusnezoline)和峨翠灵( omeieline)分别分自中国特产毛茛科植物北草乌(Aconitum hkusnezoffii Paritz)、彭州岩乌头(A. racemulosum var. pengzhouense)和峨眉翠雀花( Delphinium omeiense W. T. Wang)。应用2D NMR技术(~1H-~1H COSY, HMQC, HMBC, NOESY)全面归属了这两个生物碱的~1H和~(13)C信号的化学位移。 相似文献
166.
1 INTRODUCTION In 1984, thiolate ligand was successfully introduced into molybdenum carbonyl compound by the reaction of Mo(CO)6 with [Et4N]SR( R = C6H5, But) in a moderate condition[1]. From then on, a series of dinuclear molybdenum(0) carbonyl thiolate compounds have been synthesized and characterized by using a variety of thiolate ligands in our research group. It was found that a planar Mo2S2 unit is in the compound [Et4N]2[Mo2(CO)8(SC6H4-CH_3-p)2][2] (2) and a "butterfly" t… 相似文献
167.
报道了8个2,4-二氨基-5-取代苄基嘧啶衍生物的电子轰击质谱及碰撞活化解离和质量分析离子动能谱.该谱提供了化合物醚键及2,4-二氨基-5-取代苄基嘧啶环的主要碎裂途径,总结了一些裂解规律,将有助于这类化合物的结构推断。 相似文献
168.
5-氟尿嘧啶-1-乙酸合铜(Ⅱ)的合成及其与DNA的作用 总被引:1,自引:0,他引:1
The 5-fluorouracil-1-acetic acid (5FuAA) and its Cu(Ⅱ) complex (5FuAACu) were synthesized and the date for the crystal complex was obtained. The interaction of 5-fluorouracil-1-acetic acid (5FuAA) and its Cu(Ⅱ) complex (5FuAACu) with DNA was also investigated by using spectral, viscometric, electrochemical and agarose gel electrophoresis methods. The results of interaction with DNA suggest that both 5FuAA and 5FuAACu can bind to DNA in a static electricity attraction mode. But the attraction of 5FuAACu is greater than that of 5FuAA. 相似文献
169.
明胶中α组分含量对明胶/羟基磷灰石复合材料力学性能的影响 总被引:1,自引:0,他引:1
选用α组分含量分别为20.5%,41%和50%的A、B、C 3种明胶作为原料,采用同时加入法制备了明胶/羟基磷灰石(HAP)复合材料.通过对干态复合物膜拉伸性能的测试和对比,发现,明胶α组分含量的变化对复合材料的弹性模量影响较大,而对拉伸强度和断裂伸长率的影响则相对较小,但总的来说,三者均随α组分含量的增加而增大.其中,α组分含量最高的复合物C的拉伸强度为86.40 MPa,弹性模量为2682.35 MPa,断裂伸长率为8.65%.另外,对复合物C基本性质的表征结果表明,该材料具有类似于自然骨的组成和结构性质,因此有望成为一种具有优异力学性能的骨替代材料. 相似文献
170.
0IntroductionRareearthsarenowappliedwidelyinChina,whichcanimprovecropsyieldsandthetheirqualit-ies犤1犦.Thebeneficialeffectsmaybeduetothestimu-latoryeffectsoftheseelementsonthenutrientuptakebyplantsorontheincreasingofchlorophyllsynthesisintheplants犤2犦.Whilealotofresearcheshavebeendoneontheimprovednutritionofcropsafterapplica-tionofrareearths,muchlessattentionhasbeenpaidtothedeteriorationofsoilqualityduetotheapplicationofrareearthsforyears犤3犦.Scientistshavediscoveredthataccumula… 相似文献