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31.
32.
A. Yu. Tolbin V. E. Pushkarev L. G. Tomilova N. S. Zefirov 《Russian Chemical Bulletin》2006,55(7):1155-1158
New planar binuclear phthalocyanines sharing the benzene ring were synthesized and their spectral properties were studied.
Intense absorption in the near-IR region (∼850 nm) was observed for the first time.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1112–1115, July, 2006. 相似文献
33.
James O'Donnell Bruno Rusterholz Barbara Aebersold Denise Rüegg Wilhelm Simon Ernö Pretsch 《Mikrochimica acta》1994,113(1-2):45-52
In an investigation of octamethylene bis(malonic acid diamides) and their selectivities for magnesium, it was found that presence of secondary amides within the particular ionophore played a considerable role in the enhancement of magnesium selectivity. Similar effects in other ionophores, i.e. tris(malonic acid diamides), were thus systematically looked at with the help of selectivity measurements with the hope of optimizing the number of secondary and tertiary amides so as to improve the magnesium selectivity. The syntheses of several investigated tris(malonic acid diamide) isologues are equally reported.Deceased in November 1992 相似文献
34.
合成了两种新的聚醚取代的水杨醛亚胺Schiff碱锰(III)配合物MnL12Cl和MnL2Cl,研究了它们与表面活性剂2Brij35形成的金属胶束对BNPP的催化水解反应.探讨了催化反应机理,提出了水解反应的动力学数学模型;计算了催化反应的Michanelis常数和表观活化能,并与不含聚醚链的类似物MnL2Cl比较,考查了配合物配体中聚醚支链及其3端基对催化水解反应的影响.结果表明,催化水解反应遵循金属-氢氧离子机理;以羟基作为聚醚链端基的MnL12Cl的催化活性最高,在相同条件下,其表观一级速率常数约为MnL2Cl的3倍,为MnL2Cl的30倍.23 相似文献
35.
Shin-Ichi Hirano Toshinobu Yogo Ko-Ichi Kikuta Wataru Sakamoto 《Journal of Sol-Gel Science and Technology》1994,2(1-3):329-334
The sol-gel processing is one of promising methods to fabricate well-derived integrated thin films at relatively low temperature. Ferroelectric niobates films do afford the possibilities for adding the values by the hybridization with semiconductor and/or electro-optic systems. The molecular level designing of the precursor solution was stressed as well as the control of key processing factors. The advantages of this sol-gel have been extended to prepare the ferroelectric Pb(Mg, Nb)O3-PbTiO3 solid solution films integrated on Si wafers. The crystallization of the films with desired crystal structure could be promoted by the controlled partial hydrolysis of designed alkoxide solution in the intermediate state and the pre-heated treatment of alkoxide-derived films in flow of water vapor and oxygen gas mixture. 相似文献
36.
37.
四元交互体系Li+, Mg2+/SO42-, B4O72-—H2O25℃溶解度和溶液物化性质的研究 总被引:7,自引:0,他引:7
研究了Li+,Mg2+/SO42-,B4O72-—H2O四元交互体系25℃时的溶解度和溶液的密度及折光率.四种原始组份未发生脱水作用,体系中也没有复盐或固溶体形成.体系25℃溶解度等温线由五段组成,有四个结晶区,分别对应于四种原始组份,其中以MgB4O7·9H2O的结晶区最大.溶解度等温线上有两个零变量点,其一为MgB4O7·9H2O,MgSO4·7H2O,Li2SO4·H2O三盐共饱点,另一为MgB4O7·9H2O,Li2B4O7·3H2O,Li2SO4·H2O三盐不相称共饱点. 相似文献
38.
The investigation of the electrochemical reduction and the adsorption of meso-tetra(4-trimethylammoniumphenyl)porphine (T(4-TMAP)P) at a mercury electrode in alkaline solution shows that the overall reduction involves three two-electron steps, of which the first step is reversible and the latter two are irreversible. In addition, T(4-TMAP)P and its metal complexes of Cu(II) and Mg(II) can be strongly adsorbed on the surface of a mercury electrode. The adsorption phenomena have been utilized as a preconcentration step for the determination of trace amounts of the two ions by single sweep polarography. For copper, the detection limit is 1 × 10–8 mol dm–3, for magnesium, 1 × 10–7 mol dm–3, the latter being limited by the reagent blank. The proposed method was applied to the determination of Cu and Mg in various types of samples (chemicals, hair and liver tissues) with satisfactory results. 相似文献
39.
Thermo-oxidative stability of HDPE/EVA blends can be considerably increased by combination of a high-molecular weight phenolic antioxidant and zinc stearate. In this work, the post-irradiation thermal stability of HDPE/EVA blends has been studied. High-density polyethylene and its blends with ethylene-vinylacetate copolymer in both pure form and mixed with Irganox 1010 and zinc stearate were exposed to electron beam radiation at doses between 80 and 150 kGy, at room temperature, in air. In order to evaluate the thermal stability of the samples, post-irradiation heat treatments were done in both hot water bath at 95 °C and in an oven at 140 °C. The mechanical properties and changes in the chemical structure were determined during thermal aging in hot water and oven. The gel content was enhanced by increasing EVA concentration in all applied doses. The stabilized blends have lower gel content than the unstabilized samples. From the results of heat aging treatments it was observed that the thermal stability of the unstabilized blend samples was lower than HDPE. Thermal stability of the samples has been improved by incorporation of Irganox 1010 and zinc stearate. Formation of hydroxyl group was insignificant for stabilized samples during heat aging in both conditions. Also, the changes in the value of oxidation induction time (OIT) for the stabilized samples were negligible after prolonged immersion in hot water. 相似文献
40.
The thermokinetics of the formation reactions of cerium(III) n-dodecylbenzene sulfonate and cerium(III) stearate are studied by using a microcalorimeter. On the basis of experimental and
calculated results, three thermodynamics parameters (the activation enthalpies, the activation entropies, the activation free
energies), the rate constant, three kinetic parameters (the activation energies, the pre-exponential constant and the reaction
order) and the enthalpies of the reaction of preparing cerium(III) n-dodecylbenzene sulfonate in the temperature range of
20–35°C and cerium(III) stearate in the temperature range of44.6–62.8°C are obtained. The results showed that the title reactions
easily took place in the studied temperature.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献