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991.
0 IntroductionMetallosupramolecular oligomers and polymerscan result from the interaction of metal ions with ap-propriate multidentate ligands designed for multinucle-ar binding[1,2], and there are considerable interests in thedesign of species containing known numbers of metalions in defined spatial arrangements. The electronic andphotophysical properties of oligopyridine complexes oftransition-metal ions make their incorporation particu-larlyattractive and the possibilityofinter-metallic ele… 相似文献
992.
993.
Polyvinyl alcohol carriers bearing active amide and active ester groups were prepared by acetaliza-tion of granular macro-reticular water-insolub1e PVA with glyoxylic acid or p-formylbenzoic acidand further activation reaction with benzotriazole or N-hydroxysuccinimide using DCCI as con-densation agent. The active amides or active esters obtained were easy to react with amines suchas n-butylamine or proteins under mild condition. Ovomucoid, an inhibitor of trypsin was immo-bilized on the above-obtained reactive PVA carrier to give effective affinity adsorbent for the separa-tion or purification of trypsin. 相似文献
994.
CdSe纳米线阵列的制备及其表征(英) 总被引:1,自引:0,他引:1
通过在含有SeSO32-和Cd2+的室温水溶液中,用模板-电沉积法在纳米孔阵列阳极氧化铝膜(AAM)模板中制备了高有序性的CdSe纳米线阵列,并对其形貌、结构和组分进行了表征。扫描电子显微镜(SEM)和透射电子显微镜(TEM)结果表明,纳米线阵列中的CdSe纳米线具有相同的长度和直径,分别对应于使用的AAM模板的厚度和孔径;X-射线衍射(XRD)和X-射线能谱(EDAX)结果表明,CdSe纳米线中Cd和Se的化学组成非常接近于1∶1,其结构为立方CdSe。另外,对模板-电沉积法制备CdSe纳米线的机理进行了讨论。 相似文献
995.
Er~(3 ),Ho~(3 )和Tm~(3 )在硫氧化钆中的余辉发光 总被引:4,自引:0,他引:4
非放射性长余辉磷光粉作为美化和清洁光源在发光陶瓷、交通安全标志、紧急突发事件的照明设施、工艺美术涂料等众多领域得到越来越广泛的应用,引起人们的重视.到目前为止,文献报道的稀土长余辉磷光体的激活离子主要有铕离子(Eu3+和Eu2+[1-4]、三价铈离子(Ce3+)[5]、三价铽离子(Tb3+)[6]、三价镨离子(Pr3+)[7]、三价钐离子(Sm3+)[8].Ho3+,Er3+,Tm3+等稀土离子作为红外上转换发光材料的激活离子[9~12],而关于它们的长余辉发光的报道极少.最近,雷炳富等在Tm3+离子[13]激活的硫氧化钇体系中发现了长余辉发光.在此,我们通过高温固相法合成了Er3+,Ho3+和Tm3+掺杂的硫氧化钆长余辉磷光粉,观察到该体系中迄今未见文献报道的Er3+,Ho3+和Tm3+离子的长余辉发光. 相似文献
996.
Several novel N′-[(1-ferrocenylethylidene)amino]-N′-β-D-glycopyranosylthioureas have been efficiently synthesized via a six-step procedure, utilizing three monosaccharides (D-glucose, D-galactose and D-xylose) as starting materials, respectively. They have been preliminarily determined to display biological activity against certain fungi. The target compounds have been unambiguously characterized by spectroscopic method and elemental analysis. An initially alternative synthetic route, which was seemingly reasonable, has been excluded due to its inefficiency. 相似文献
997.
在四氢呋喃溶液中,用Sm/TiCl4体系还原亚胺合成了咪唑烷衍生物.发现当没有促进剂1,2-二溴乙烷时,咪唑烷衍生物的产率小于20%,加入1,2-二溴乙烷后,产率大大提高.产物的结构通过IR,1HNMR和MS光谱确证.根据实验结果提出了一个可能的反应机理. 相似文献
998.
999.
1000.
The alkyl polyglycosides (APG) is new type the surfactants that is made by regenerationresource of the starch and the grease, since the nineties of 20th century it is energetically exploited ininternational extent. APG not only good in surface activity, but also plenty on bubble, thin greasyand stabilization, there are good decontamination, compatibility, innocuity, not incitation and uniquefunction that organism decomposition of swiftness and downrightness, and so on.APG is to get production that loses one molecule water with half condensation aldehyde hydroxyand sebum alcohol hydroxy under acid catalysis. The production not is one simplicity compound, butis one of sugar polymerization degree, so it is mixture of the alkyl single glucoside, the alkyl twoglucoside and the alkyl three glucoside.Author synthesizes the surfactants of the alkyl polyglycosides, with the oleaster and potato starchand sebum alcohol, that was chosen to use duality system activator of plant acid and p-toluene-sulfoacid for the first time. The adoption way is that the lower alkyl polyglycosides is firstly formed byreaction of lower alcohol with starch then exchanged with high alcohol to obtain APG. The study isto make certain most technics condition, determining capillary tension and the pastern sheafdeepness of critical, calculating HLB value, determining construction by 1R.To synthesize principium:Peroration :[1]Duality system activator of plant acid and p-toluene-sulfo acid is compare idea activator that was the lower alkyl polyglycosides is firstly formed by reaction of lower alcohol with glucose then exchanged with high alcohol to obtain high alkyl polyglycosides. The advantage is that it overcomes agglomeration, there is reaction entirety, high of sugar transform ratio, reaction time short.[2]Most good reaction temperature is 90~ 170℃, the dosage of activator is 0.5%~0.9%, the mated ratio: The APG of glucose basic butane ratio starch is 5:1, the APG of potato starch basic glycol ratio starch is 6:1, the APG of the oleaster starch basic glycol ratio starch is 12:1, the APG of the mealiest starch basic glycol ratio starch is 6:1, the product of complex is good property.[3]The alkyl polyglycosides is the products of surfactant. IR determines the functional group of the products. On the basis of group of the hydrophile and to close on oil, that the feature peak of α-1, 4- glucoside.[4]The capillary tension of the APG is 26.8~31.0mN/m, the HLB value is 16~18, the products is better emulsifying agent of water- solubility. (O/W). 相似文献