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901.
Gérald Perron Jean-François Côté Daniel Lambert Johanne Pageau Jacques E. Desnoyers 《Journal of solution chemistry》1994,23(2):121-133
Blends of immiscible polymers are often stabilized by block copolymers which can form non-aqueous micelles and microemulsions in the liquid polymers. The phase diagrans, apparent volumes and apparent heat capacities of model non-aqueous binary and ternary systems were studied in order to investigate the conditions under which such self-assembly systems could form. 1,2-Hexanediol, which can cosolubilize hexane and ethyleneglycol, forms inverse micelles in hexane and weak microaggregates in ethyleneglycol. Genapol X-060, a commercial alcoholic surfactant containing on the average an aliphatic chain of 13 carbons and 6 oxyethylenes (C13E6), forms microaggregates in poly(ethyleneglycol) 400. These self-assembly systems are strengthen in the presence of a third component which has an affinity for the inner phase.Presented at the Symposium, 76th CSC Congress, Sherbrooke, Quebec, May 30–June 3, 1993, honoring Professor Donald Patterson on the occasion of his 65th birthday. 相似文献
902.
The mer‐octahedral complexes(2‐carbonyl)(4‐Me)(6‐tBu)phenolato[C,O]hydridotris(trimethylphosphine)cobalt(III) ( 1 ) or ‐(1‐carbonyl)(2‐oxo)(1,2‐diphenylethene)[C,O]hydridotris(trimethylphosphine)cobalt(III) ( 2 ) via formal insertion of propynoic acid ethyl ester into Co‐H functions afford pentacoordinate vinylcobalt(III) 3 and 4 , respectively, that are diamagnetic and attain a square pyramidal structure as exemplified by an X‐ray diffraction analysis of 3 . 相似文献
903.
建立了一种人工神经网络-X射线荧光光谱法测定钢中酸溶铝的方法,用X射线荧光光谱法测定低合金钢中总铝值,应用所建立的ANN-BP网络模型,输入总铝含量直接预测出酸溶铝含量。同时使用改进的BP算法,避免了神经网络学习中可能产生的麻痹现象。该方法用于钢中酸溶铝的测定,结果满意。 相似文献
904.
Wieczorek-Ciurowa K. Gamrat K. Shirokov Ju. G. 《Journal of Thermal Analysis and Calorimetry》2003,72(1):323-328
A catalytic action of the mechanochemical products of copper hydroxocarbonate with calcium carbonate was investigated in n-butyl
alcohol oxidation tests. The solid products of high-energy milling were identified using thermogravimetry supplemented by
X-ray diffraction method. It was shown that the mechanical activation induces more effective tested catalyst because it promotes
the alcohol conversion at lower temperatures than that unmilled one.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
905.
I. V. Dlinnykh G. A. Golubeva I. F. Leshcheva V. V. Nesterov M. Yu. Antipin L. A. Sviridova 《Chemistry of Heterocyclic Compounds》2004,40(9):1142-1149
The reaction of oxindoles with 5-hydroxypyrazolidines on the surface of potassium fluoride-modified alumina leads to 3-(5-pyrazolidinyl)oxindoles. The structure of these products was studied. 相似文献
906.
Dan Donescu Sever Serban Kristiana Gosa Cristian Petcu 《Central European Journal of Chemistry》2005,3(1):10-27
The possibility to prepare hybrids made by poly(vinyl acetate) (PVAc), poly(methyl methacrylate) (PMMA) and/or poly(ethyl
acrylate) (PEtA) with TiO2 was studied. The processes of polymer formation-radical polymerization and sol-gel process for inorganic network —were achieved
simultaneously. Due to a high reactivity of titanium isopropoxide (TIP) in the sol-gel process, a complexant comonomer, allyl
acetoacetate (AlAcAc), was used. Covalent bonds between polymer and inorganic chains were obtained by addition of trialkoxysilane
derivates with vinyl (VTES) or methacryloyl (MPTS) groups. The presence of TIP inhibits the radical polymerization of vinyl
acetate (VAc). The PVAc-TiO2 hybrids were produced by the sol-gel process of TIP in the presence of pre-obtained PVAc. Except for VTES and MPTS, trialkoxysilane
derivates with methyl (MeTES), octyl (OTES) and phenyl (PTES) groups were used. The thermal stability of hybrids is strongly
affected by TiO2 presence and by the type of trialkoxysilane derivates. The thermal stability of PVAc hybrids decreases in the presence of
TiO2 inorganic network. The glass transition temperature of polymers increases in the presence of the inorganic network. 相似文献
907.
WANG Shufang GUO Tianying TAO Jian ZHENG Chenggang ZHANG Banghua SONG Cunjiang 《反应性高分子(英文版)》2005,14(1):1-7
Blends of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) and poly(butylene succinate-adipate) (PBSA), both biodegradable semicrystalline polyesters, were prepared with the ratio of PHBHHx/PBSA ranging from 80/20 to 20/80 by melt mixing method. Differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), dynamic mechanical thermal analysis (DMA), polarizing optical microscopy (POM) and wide angle X-ray diffractometer (WAXD) were used to study the miscibility and crystallization behavior of PHBHHx/PBSA blends. Experimental results indicate that PHBHHx is immiscible with PBSA as shown by the almost unchanged glass transition temperature and the biphasic melt. 相似文献
908.
909.
F. A. L. van der Horst M. H. Post J. J. M. Holthuis U. A. Th. Brinkman 《Chromatographia》1989,28(5-6):267-273
Summary Micellar phase-transfer catalysis (MPTC) offers the opportunity to derivatize carboxylic acids directly in an aqueous matrix without prior extraction of the acids into a suitable aprotic solvent. The currently developed MPTC system consists of a non-ionic surfactant, Arkopal N-130, an ion-pair agent, tetrakis-(decyl)-ammonium bromide, and a novel fluorescence reagent, 9-bromomethylacridine. The MPTC system can be applied to the derivatization of many types of carboxylic acids. The reaction rate is affected by the lipophilicity of the acid and by the presence of other functional groups. For lipophilic carboxylic acids the reaction is complete within 5 min at 60°C and pH 7.0. 相似文献
910.
Pullin等人曾对全氟碘代烷与三级胺的相互作用进行了研究,发现R_(?)I与NR_3能形成电荷转移络合物,即:R_(?)…I…NR_3。但此后却未见到有关反应的报道。我们发现在钯催化剂存在下,全氟碘化物与三乙胺能发生反应,反应条件较为温和,产物为氟代烷基烯基二乙基胺1。反应可能是在三乙胺中先产生一个双键,然后β碳原子接上一个全氟烷基。1的IR和NMR与Blanc报道的一致。化合物1经水解可得胺基烯酮2。在酸溶液中水解时,速度明显加快,而在碱溶液中,不仅不能加快水解速度,而且还有副反应发生。我们对化合物2进 相似文献