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1.
研究了Fe(acac)3-Al(i-Bu)3-8-羟基喹啉(acac=乙酰丙酮)催化体系催化丙烯酸丁酯(BA)聚合,考察了聚合规律,用凝胶渗透色谱研究了聚合物分子量和分子量分布.动力学研究表明聚合反应对单体浓度呈一级关系,表观活化能为13.9kJ/mol. 相似文献
2.
A continuous precipitation flame atomization atomic absorption spectrometric method for the indirect determination of sulphate is proposed. By using a reversed flow-injection configuration for precipitation as barium sulphate, this anion was determined in the range 10–150 g/ml, with a relative standard deviation of 2.6%. The sensitivity was increased by a factor of seven by using a nitrous oxide-acetylene flame to measure barium. 相似文献
3.
4.
硫酸根的分光光度法测定 总被引:6,自引:0,他引:6
本文就硫酸根的间接及直接光度测定的基本原理,试剂,方法和应用等作了较为系统的评述。列出重要文献67篇。 相似文献
5.
Excess volumes V
E
of binary liquid mixtures of quinoline with alkanols have been determined from densities at 30°C as a function of composition. The excess volumes are negative over the whole mole fraction range for all the mixtures and decrease with increasing length of alkanol (C1–C10). The VE data have been analyzed in terms of an approach which uses graph theoretical connectivity parameters of the third degrees for two components. The analysis gives information regarding associated species in the pure state and in the mixture. It is suggested that, in the mixture state, no change occurs in the association of alkanols. 相似文献
6.
7.
8.
Ramendra Pratap 《Tetrahedron letters》2007,48(15):2755-2759
A concise synthesis of highly functionalized 5,6-dihydrobenzo[h]quinoline-3-carbonitriles is delineated through base induced ring transformation of 4-sec-amino-2-oxo-5,6-dihydro-2H-benzo[h]chromene-3-carbonitriles with S-methylisothiourea sulfate and 1-carboxamidinepyrazole hydrochloride, separately, in DMF. Under analogous reaction conditions the ring transformation of 4-sec-amino-2-oxo-5,6-dihydro-2H-benzo[h]chromene-3-carbonitriles by formamidine acetate provided 4-sec-amino-benzo[h]quinoline-3-carbonitriles in moderate yields, while with benzamidine hydrochloride, the reaction followed the same mechanism to yield 2-phenyl-4-sec-amino-5,6-dihydrobenzo[h]quinoline-3-carbonitriles. 相似文献
9.
Recent data on classical and modified methods for the synthesis of quinoline systems by the Skraup and Doebner-Miller reactions,
not included in reviews on heterocycles, are discussed.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 803–824, June, 2006. 相似文献
10.
Interactions of anionic surfactant sodium dodecyl sulphate (SDS) with vesicles formed by synthetic dialkyldimethylammonium
bromides i.e. didodecyldimethylammonium bromide (DDAB), ditetradecyldimethylammonium bromide (DTAB), dihexadecyldimethylammonium
bromide (DHAB) have been examined by using differential scanning microcalorimetry and electron transmission microscopy. The
temperatures and standard enthalpies characterising gel to liquid-crystal transitions increase significantly with increase
of SDS concentration for all investigated systems. It means that incorporation of SDS monomers in these vesicular bilayers
significantly stabilises their gel states. Moreover, in case of DDAB and DTAB vesicle systems added SDS limits kinetic features
of recorded isobaric heat capacity dependencies on temperature observed earlier for the pure vesicular solutions.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献