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41.
两组份互穿网络聚合物的合成研究 总被引:1,自引:0,他引:1
以蓖麻油聚氨酯和聚醚聚氨酯的不同重量比与光敏剂、催化剂、稀释剂、促进剂所组成的多相体系为反应物,分别在紫外光照射和加热的条件下合成网络Ⅰ和网络Ⅱ的互穿网络聚合物(IPN)。改变网络Ⅱ聚醚聚氨酯中各组份的摩尔比制得系列样品。红外光谱,应力-应变曲线和动态力学性能测定发现,样品的力学性能与两组份重量比和网络Ⅱ中不同组成都存在着一定关系。这些结果,为该体系IPN的合成和应用提供了一定依据。 相似文献
42.
Two new dicyanamide coordination polymers, {Mn(dmpz)[N(CN)2]2}2 (1) and {Cu(dmpz)[N(CN)2]2}2 (2)(dmpz=3,5-dimethylpyrazole), were synthesized and characterized by single crystal X-ray diffraction analysis and IR spectroscopy. In 1 and 2 the metal ions have two different coordination modes, where one is coordinated to four dicyanamide anions and two monodentate dmpz molecules to form a slightly distorted octahedral geometry, while the other adopts octahedral geometry, surrounded by four nitrile N atoms and two amide N atoms of the dicyanamide anions. Both complexes contain two alternating chains that are parallel to each other. 相似文献
43.
依据柱相比的热力学定义和反相液相色谱中溶质的计量置换保留理论(the stoichiometric dispheement heory of solute for retention,SDT-R),对反相液相色谱中固定相和流动相性质、温度对柱相比的影响进行了研究。结果表明:固定相的种类和配基的疏水性对柱相比影响较大,而流动相中有机溶剂的种类,特别是脂肪酸作为置换剂时,对柱相比的影响更大,而柱相比受温度的影响较小。此外,通过用27种小分子溶质对柱相比的测定,其logI和Z良好的线性关系,进一步证明柱相比是一个与溶质性质无关的常数。 相似文献
44.
With frontal analysis(FA),the dependence of adsorption isotherms of insulin on the composition of mobile phase in reversed phase liquid chromatography (RPLC) has been investigated,This is also a good example to employ the stoichiometric displacement theory (SDT) for ivestigating solute adsorption in physical chemistry.Six kinds of mobile phase in RPLC were employed to study the effects on the elution curves and adsorption isotherms of insulin.the key points of this paper are:(1) the stability of insulin due to delay time after preparing,the organic solvent concentration,the kind and the concentration of ion-pairing agent in mobile phase were found to affect both elution curve and adsorption isotherm very seriously.(2)To obtain a valid and comparable result,the composition of the mobile phase employed in FA must be as same as possible to that in usual RPLC of either analytical scale or preparative purpose.(3)Langmuir Equation and the SDT were employed to imitate these obtained adsorption isotherms.The expression for solute adsorption from solution of the SDT was found to have a better elucidation to the insulin adsorption from mobile phase in RPLC. 相似文献
45.
Geng J Ducati C Shephard DS Chhowalla M Johnson BF Robertson J 《Chemical communications (Cambridge, England)》2002,(10):1112-1113
A nanoscale ruthenium/gold bimetallic cluster of clusters has been used as a molecular precursor to produce pure ruthenium nanoparticles (seeds) as catalysts for the growth of carbon nanohorns (CNHs). 相似文献
46.
The refolding of the reduced-denatured insulin from bovine pancreas was investigated with the size exclusion chromatography (SEC). It was shown that the reduced-denatured insulin originally denatured with 7.0 mol L?1 guanidine hydrochloride (GuHCI) or 8.0 mol L?1 urea could not be refolded with a non-oxidized mobile phase. Although the oxidized and reduced glutathione (GSSG and GSH) were employed in the oxidized mobile phase, the reduced-denatured insulin still could not be renatured. However, in the presence of 2.0 mol Lt-1 urea in the oxidized mobile phase employed, the reduced-denatured insulin can be refolded with SEC, and the aggregation of denatured insulin can be diminished by urea. In addition, the disulfide exchange of reduced-denatured insulin also can be accelerated with GSSG/GSH in the oxidized mobile phase. The three disulfide bridges of insulin were formed correctly and the reduced-unfolded insulin can be renatured completely. The results were further tested with reversed-phase liquid chromatography (RPLC) and hydrophobic interaction chromatography (HIC). 相似文献
47.
Jingcheng Hao Hanqing Wang Shuo Shi Runhua Lu Taotao Wang Ganzuo Li Haiying Sun 《中国科学B辑(英文版)》1997,40(3):225-235
By the orthogonal design, the optimal formation conditions for the middle-phase microemulsions in the system dioctadecyldimethylammonium
chloride (DODMAC)/ sodium dodecyl sulfate (SDS)/n-butanol/n-hep-tane/brine were obtained as follows: WDODMAC: WSDS = 1:4-1:5,C
π-butanol (%) = 11.0-12.0, andC
NaCl (%) = 3.25
Investigations have been made on the effects of the concentrations of NaCl and n-butanol (l.0%-14.0%), the ratios ofWDODMAC: to WSDS, and the kinds of alcohols (n-propanol, n-butanol, and n-pentanol) on the formation, the phase behaviour, the ultralow interfacial
tensions, the optimal salinity (S*), and the length of salinity (δS). Some rules and data were worked out about the formation and characteristics of the middle-phase
microemulsions. The mi-crostructures of the middle-phase microemulsions were also studied by using FT-IR, ESR, and freeze
fracture electron microscopy techniques. The results from the three methods show that the microstructures of the middlephase
mi-croemulsions undergo the change from O/W to bicontinuous (B.C.) and to W/O. The distribution rule of the orga-nized molecule
assemblies in the middle-phase microemulsions is conducible to constructing the model of microemulsion systems, to recognizing
the microstructures of the middle-phase microemulsions, and to setting forth the relationship between the microstructures
and macro-properties of rnicroemulsions.
Project supported by the Niltional Natural Science Foundation of China and the Chinese Postdoctoral Science Foundation. 相似文献
48.
在一定条件下,精胺不仅能够与脱氧核糖核酸(DNA)大沟嵌入结合,还能与DNA链上的碱基和磷酸基进行链内结合和跨链结合,形成致密的环状螺旋结构,造成DNA的凝聚,从而使DNA共振光散射(RLS)强度强烈地增强。增强的共振光散射强度与精胺的浓度呈现良好的线性关系,线性范围为5.0×10-7~1.0×10-5mol/L;校正曲线的回归方程为IRLS=40.22 5.28×107C(mol/L),相关系数r=0.9936;检出限(3σ)为7.4×10-8mol/L。在测定精胺的线性范围内,其它多胺(亚精胺,腐胺)、蛋白质及常见的金属离子不干扰测定。该方法用于测定新几内亚凤仙中的精胺,获得满意结果。 相似文献
49.
Jing Xu Yibao Li Lejia Wang Xiaoyang Zhu Xunwen Xiao Yanfang Geng Ke Deng Qingdao Zeng 《中国化学快报》2019,30(3):767-770
Because of the effect of pyridine on the substituent position on the TTF group, TTF derivatives exhibit different assembly structures at the interface, which will be of great significance to the construction of functional nanostructures from the molecular design point of view. 相似文献
50.
比值光谱导数法同时测定铝合金中铁,铜,锌 总被引:6,自引:0,他引:6
用比值光谱-导数分光光度法,在pH5.5缓冲溶液中,利用金属-2-(5-溴-2-吡啶偶氮)-5-二乙氨基酚(5-Br-PADAP)-OP三元络合物显色体系,对混合物中铁,铜,锌三组分进行了同时测定。合成试样5次测定回收率在97.3%-104.4%之间。应用于铝合金中铁,铜,锌的测定,各6次测定的RSD分别为3.66%,1.38%,2.03%。 相似文献