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201.
The dimerization constant (Kg) of acrylic acid and the association constant of the comonomer complex between acrylic acid and 1-vinyl-2-pyrrolidone (K1) have been determined in chloroform by means of IR and 1H NMR spectroscopy: Kd=(2.0±0.2) × 103litre mol?1 and K1=68.5±0.5 litre mol?1. A detailed equation for the copolymer composition considering the participation of the intermolecular complexes in the chain propagation has been derived with the help of a specific regular three addition states Markov chain. Applying a numerical procedure for fitting the experimental curve for the comonomer composition, this equation has been used in the estimation of the dimer and the comonomer complex relative reactivities. The considerably higher reactivities of the two complexes compared with that of the monomers are accounted for by the π-electrons' greater delocalization in the transition states involving the complexes species. 相似文献
202.
The association constant of the H-complex formation between acrylic acid and 1-vinyl-2-pyrrolidone in tetrahydrofuran at 22°C (K1 = 1350 mol 1?1) was determined by means of 1H NMR spectroscopy. A detailed equation for the copolymer composition, accounting for the participation in the chain propagation of the above complex and that between acid and solvent molecules, was derived. It was used for evalution of the relative reactivities of the complexes discussed and of the uncomplexed 1-vinyl-2-pyrrolidone molecules. 相似文献
203.
唐云丽 《核电子学与探测技术》1984,(6)
本文叙述了基于SEED-80微型计算机的实时数据获取与处理统软件的设计及其功能。该软件系统灵活、方便。其主要功能监视与控制各实时数据获取通道,管理计算机各外围设备并按用户的要求进行数据处理。在程序设计上,由于采用了类似于模块程序方法和复盖技术,因而对计算机内存进行了有效的分配与管理并实现了前后台操作。 相似文献
204.
Herbert C. Wilkinson 《Fuel》1984,63(1):101-108
The chemical composition and the physico-chemical properties of a suite of British coals, mainly of types 501/2 as defined by the NCB classification, but including some coals of higher and lower rank (NCB classification 204,401/2 and 601/2), were comprehensively investigated. Each coal was subsequently carbonized under controlled conditions of size distribution, bulk density and temperature on the 250 kg scale and the tensile strength, coke structure and coke reactivity were determined. This data highlighted the significance of the atomic ratio of the oxygen and carbon of the coals and the lack of relations between coal properties and coke structure and strength. As regards coke reactivity only complex relations with coal properties could be found, with coal rank, the oxygen/carbon ratio and the chlorine content being of greatest importance. 相似文献
205.
Copolymerisation of styrene and isoprene by constant potential electrolysis in dichloromethane was achieved at different polymerisation potentials. Effect of ultrasonic vibration on the rate and the yield of polymerisation has been discussed. The composition of the copolymers was found to be affected by the vibration as well as the polymerisation potential (Epol). At Epol=+3.30 V we found that r1=r2 and mole percents of isoprene and styrene in copolymer were equal to each other. Equality was also observed on reacted monomer concentrations, at that potential, which can be called critical polymerisation potential. At Epol values above or below the critical polymerisation potential none of the above-mentioned properties were equal. Monomer reactivity ratios were determined by the integrated Lewis-Mayo equation. Ultrasonic vibration as well as polymerisation potential was found to affect reactivity ratios. 相似文献
206.
The hypothesis tested was that the more definitely one distinguishes the right and left sides of his body in his body image, the more likely he is to show differential reactivity in the left vs. right sides of his body. Ss compared homologous body parts while viewing them through aniseikonic lenses to determine body-image differentiation. Body reactivity was determined by means of GSR recordings. Right handed Ss who clearly distinguished their right and left body sides were likely to show a GSR gradient showing the left side to be more reactive than the right. 21 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
207.
Resting skin-resistance, heart-rate, and reactivity data to 1 of 2 tension-arousing films were obtained from 2 normal comparison groups and a sample of drug-free chronic schizophrenics. The schizophrenics were subdivided into 3 subsamples on the basis of the number of deviant associations given to a word-association test. The resting skin-resistance data failed to discriminate between normals and schizophrenics; however, meaningful differences were found among the schizophrenic subsamples such that increasing thought disturbance was associated with increasing basal resistance levels. Basal heart-rate data did indicate faster heart rate for all schizophrenic subsamples compared with both normal groups. Reactivity data also indicated different results for the 2 indexes. Skin-resistance indexes failed to indicate any differences between schizophrenics and normals or among the schizophrenic samples. 1 heart-rate index suggested less reactivity for schizophrenics than for normals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
208.
利用相转移催化技术合成正丁基苯基醚的探讨 总被引:2,自引:0,他引:2
本文讨论了利用相转移催化技术合成正丁基苯基醚。并与无催化剂方法进行了比较,从反应机理方面研究了影响反应的某些因素。 相似文献
209.
Strong links have been documented between life events and the course of bipolar disorder. Laboratory studies of stress provide an opportunity to understand the mechanisms involved in reactivity to stressors, but few such studies have been done in the bipolar field. In the current study, 28 people with bipolar I disorder in full or partial remission and 40 people with no history of a mood disorder were randomly assigned to 1 of 3 conditions involving different levels of failure feedback on a concept formation task. Confidence, affective reactions, and performance on a subsequent anagram task were assessed. Results provide tentative support for reactivity to the stressor among the bipolar group, although reactivity was limited to impaired anagram performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
210.
The copolymerization of methyl acrylate (MA), ethyl acrylate (EA), straight-chain butyl acrylate (n-BA) and styrene (S) with triallyl cyanurate (TAC) has been studied in bulk at 343±1 K using benzoyl peroxide as initiator. The reactivity ratios of the monomers are determined by the Fineman-Ross (F-R) method and compared to those determined by the Kelen-Tüdös (K-T) method. 相似文献