WCl6—Al（i—Bu）2Cl催化丁二烯—苯乙烯共聚合：丁苯共聚物的结构组…

对丁苯共聚物的＾１Ｈ－ＮＭＲ谱图进行了归属，并建立了计算其４种结构单元含量的方程式。当Ａｌ（ｉ－Ｂｕ）２Ｃｌ／ＷＣｌ６＝６（摩尔比）时，苯乙烯单元含量最低，丁二烯单元含量最高；Ｂｄ单元含量随Ｂｄ／Ｓｔ值的增加而提高，总的Ｓｔ单元含量随Ｂｄ／Ｓｔ值的增加而降低；聚合时间对单元含量的影响与Ｂｄ／Ｓｔ值的影响相似；提高聚合温度，Ｓｔ单元含量降低。用微分法求得转化率低于１０％时Ｓｔ的竞聚率为４．７０，Ｂｄ     

钨系齐格勒－纳塔催化剂引发丁二烯－苯乙烯共聚合──Ⅰ．高乙烯基丁苯共聚物的合成

以ＷＣｌ_６（Ｗ）为催化剂，分别与四种烷基铝组成催化体系，以苯乙烯（Ｓｔ）、丁二烯（Ｂｄ）为单体，在６０～７０℃下聚合５ｈ，可获得高乙烯基丁苯共聚物。结果表明，以Ｗ－Ａｌ（ｉ－Ｂｕ）_２Ｃｌ（Ａｌ）组成的催化体系，在Ａｌ／Ｗ＝３．５（摩尔比），陈化３０ｍｉｍ以上时，活性最高，所得丁苯共聚物［η］＝０．２５～０．６５ｄＬ／ｇ，乙烯基含量大于５０％（摩尔），结合Ｓｔ含量为１０％～４０％（摩尔）。     

胺对镍系催化了二烯聚合规律的影响

以二乙胺为例研究了胺对Ｎｉ（ｎａｐｈ）２－Ａｌ（－Ｂｕ）３－ＢＦ３·ＯＥｔ２＋ｎ—Ｃ８Ｈ１７ＯＨ（简称Ｎｉ－Ａｌ－Ｂ＋ＲＯＨ）和Ｎｉ（ｎａｐｈ）２－Ａｌ（ｉ－Ｂｕ）３－ＢＦ３·ＯＥｔ２＋ＣＨ３ＣＯＯＣ４Ｈ９（简称Ｎｉ—Ａｌ—Ｂ＋ＢＡ）两体系聚合活性和聚合物分子量的影响，并与Ｎｉ—Ａｌ—Ｂ体系进行了对比．考察了通常条件下肢的允许含量，讨论了有胺存在时Ｎｉ／Ｂｄ、Ａｌ／Ｎｉ、Ａｌ／Ｂ摩尔比的变化对聚合规律的影响。结果表明：胺的含量高于２０ｐｐｍ时将使聚合活性和分子量降低，提高催化剂用量可以抑制胺的不利影响。     

耐磨Ni－SiC复合电镀及其应用

含ＳｉＣ最高达１１％的Ｎｉ－ＳｉＣ复合镀层的镀液配方及操作条件为：Ｎｉ（ＳＯ_３．ＮＨ_２）_２·４Ｈ_２Ｏ４１０，ＮｉＣｌ_２·６Ｈ_２Ｏ１０，Ｈ_３ＢＯ_３５０，ＯＰ－１００．４及ＳｉＣ（３μｍ）２０－１２０ｇ／Ｌ，ｐＨ４，５５±２℃，５Ａ／ｄｍ￣２，需搅拌．     

镧系金属化合物催化苯乙烯和双烯烃的共聚──苯乙烯和异戊二烯共聚合制备高顺式－1，4嵌段共聚物

采用稀土催化体系Ｎｄ（Ｆ_３ＣＯ_２）_３－ＢｒＣ_５Ｈ_（１１）－Ｒ_ｍＡｌＨ_（３－ｍ）（Ｎｄ－Ｂｒ－Ａｌ），以甲苯为溶剂，在５０℃恒温水浴中进行苯乙烯（Ｓｔ）和异戊二烯（Ｉｐ）共聚合。结果表明，由Ａｌ（Ｏｃｔ）－３组成的催化体系可制备以顺式－１，４结构为主的共聚物；在后者组成的催化体系中，当Ａｌ／Ｎｄ＝５（摩尔比，下同），Ｂｒ／Ｎｄ＝５时，聚合活性最高。经ＩＲ，ＮＭＲ检测表征了共聚物的微观结构。同时，用π－烯丙基型配位机理和返扣配位机理对实验结果进行了定性解释。     

聚合物载体－稀土金属络合物的研究 Ⅻ．聚［苯乙烯－甲基丙烯酸β（甲基亚硫酰基）乙酯］载体－三氯化钕络合物－三异丁基铝体系催化丁二烯聚合的活性

研究了聚［苯乙烯－甲基丙烯酸β（甲基亚硫酰基）乙酯］（ＰＳＭ）载体－三氯化钕（ＮａＣ１３）络合物－Ａｌ（ｉ－Ｂｕ）３体系催化丁二烯聚合的活性与ＰＳＭ转化率和ＰＳＭ·ＮｄＣｌ３络合物组成的关系。实验结果表明，ＰＳＭ转化率为１８．１％～５３．４％，对ＰＳＭ·ＮｄＣｌ３－Ａｌ（ｉ－Ｂｕ）３体系的活性基本上无影响。低功能团含量的ＰＳＭ·ＮｄＣｌ３络合物的活性优于高功能团含量的ＰＳＭ·ＮｄＣｌ３。该络合物中Ｎｄ含量为４．５×１０（－４）ｍｏｌ／ｇ左右时，体系的催化活性最佳。体系的活性随引入的Ｌｅｗｉｓ酸的种类和用量的不同而改变。     

用TiCl_4／MgCl_2－Al（i－Bu）_3合成反－1，4－聚异戊二烯

研究了负载型钛催化剂ＴｉＣｌ_４／ＭｇＣｌ_２－Ａｌ（ｉ－Ｂｕ）_３体系合成反－１，４－聚异戊二烯的基本规律。结果表明，最适宜的聚合条件为：６０℃，Ａｌ／Ｔｉ＝１０（摩尔比），Ｔｉ／Ｉｐ＝２×１０￣（－４）（摩尔比），加料顺序为汽油－Ａｌ－Ｔｉ－Ｉｐ。预聚合可有效地提高催化剂效率，而对聚合物的分子量影响不大。     

酸性膦酸酯钕盐催化聚合丁二烯的研究

以酸性膦酸酯（Ｐ５０７）钕盐（Ｎｄ）、Ａｌ（ｉ－Ｂｕ）３（Ａｌ）和Ａｌ２Ｅｔ３Ｃｌ３（Ｃｌ）为催化体系，已烷为溶剂，进行丁二烯（Ｂｄ）溶液聚合。催化剂采用Ａｌ＋Ｎｄ＋Ｃｌ的加料方式，Ａｌ／Ｎｄ＝２０（摩尔比，下同），Ｃｌ／Ｎｄ＝３．０，室温下陈化２ｈ以上，于５０℃恒温水溶中聚合５ｈ，可得到顺式－１，４含量高于９７％，［η］大于９．０ｄＬ／ｇ的聚合物。同时证明，在相同的催化剂组分配比及聚合条件下，该     

负载钛-三异丁基铝体系催化1-丁烯聚合 Ⅰ.聚合条件对1-丁烯聚合的影响

考察了负载钛（Ｔｉ）－三异丁基铝（Ａｌ）催化体系聚合条件对１－丁烯（Ｂｔ）聚合的影响。实验表明，该催化体系对Ｂｔ聚合催化效率可达３４．８ｋｇ／ｇ，聚合物为全同立构和无规立构聚１－丁烯的混合物。在一定的Ｔｉ／Ｂｔ（摩尔比）下，随着Ａｌ／Ｔｉ（摩尔比，下同）的增加和温度的升高，转化率都是先升高后下降，最佳Ａｌ／Ｔｉ值为３００，温度为３０℃。聚合物的相对分子质量和全同立构ＰＢｔ含量均随Ａｌ／Ｔｉ和温度升高而逐渐下降。     

钨系齐格勒—纳塔催化剂引发丁二烯—苯乙烯共聚合：Ⅰ.高乙烯基丁…

以ＷＣｌ６（Ｗ）为催化剂，分别与四种烷基经催化体系，以苯乙烯、丁二烯为单体，在６０－７０℃下聚合５ｈ，可获得高乙烯基丁苯共聚物，结果表明，以Ｗ－Ａｌ（ｉ－Ｂｕ）２Ｃｌ（Ａｌ）组成的催化体系，在Ａｌ／Ｗ＝３．５（摩尔比），陈化３０ｍｉｎ以上时，活时最高，所得丁苯区聚物［η》＝０．２５－０．６５ｄＬ／ｇ，乙烯基含量大于５０％（摩尔），结合Ｓｔ含量为１０％－４０％（摩尔）。     

SEDIMENTATION OF BINARY MIXTURES OF PARTICLES OF UNEQUAL DENSITIES AND OF DIFFERENT SIZES

A model is developed for the sedimentation from a suspension of two particle species of unequal densities and of different sizes. The composition and the thickness of various layers in the sediments are predicted using graphical and analytical methods. The model predictions were in excellent agreement with experimental results, when the particle size ratio was ≥ 108. When size ratio of the particles was 2.60 and 4.31 the agreement occurred in about 50 percent of the cases.     

骑式摩托车油箱喷涂工艺的改进

面对日益激烈的市场竞争,摩托车油箱外观质量越来越成为影响销售的因素之一。文章介绍了改进工艺后的油箱涂装,该涂装体系提高了油箱外观的丰满度,降低了油箱涂装的生产成本。     

COMPARISON OF METHODS OF ANALYSIS OF GYPSUM1

The different analytical methods proposed for the evaluation of gypsum have been subjected to an experimental test. A combination method, consisting of a fusion with KHCO₃ and determination of CaO by KMnO₄ titration, the SO₃ by Andrews method of titration of BaCrO₄ has been found to give very reliable results with the least consumption of time.     

HEASUREHENT OF INSTANTANEOUS RATES OF LOSS OF VOIATILE COMPOUNDS DURING DRYING OF DROPS

A novel technique serves to monitor instantaneous rates of loss of a volatile solute from a suspended drop during drying. A highly sensitive electron capture detector is used to monitor concentrations of SF6 released into a flowing gas stream from a suspended, drying drop. Simultaneously, the appearance and morphological development of the drop are monitored with a video camera. This provides the wherewithal of relating instantaneous rates of loss of the volatile solute to particular events during the development of particle morphology.

Initial experiments have been carried out with drops of aqueous solutions of glucose, sucrose, maltodextrin and coffee extract. The results clearly display the onset of the volatiles-retentive selective diffusion phenomenon. There is also substantial loss of the volatile component later in the drying process, when the drops undergo repeated ex ansion, bursting and cratering due to the formation of internaf bubbles. These experiments appear to be the first quantitative demonstration of major losses accompanying changes in drop morphology.     

用两个形状指数表征粉煤灰颗粒形貌的研究

引用两个形状指数表征颗粒形状的概念,即先将颗粒形状近似为椭圆,再将椭圆图像分离:以圆为基准的颗粒宏观形状指数δ;以光滑椭圆为基准的颗粒轮廓凹凸度,即微观形状指数ζ。分析和发展了近似椭圆模型。并运用图像分析仪对粉煤灰、水泥样品进行实验。结果表明,粉煤灰颗粒的两个形状指数δ和ζ都大于水泥颗粒。证明粉煤灰颗粒的球形度、表面光滑度优于水泥,而且,随着粒径增大,δ和ζ呈下降趋势,表明磨制颗粒越粗。(?)粒形状越不规则。文中还运用近似椭圆模型再现了颗粒的模拟图像。     

典型煤碳燃烧特性研究和数值模拟

本文以三种典型煤的碳燃烧为研究对象，分别采用简单一维沉降燃烧方式和等温加热燃烧方式，实验研究了煤在快速加热条件下，其碳的初期和中，后期燃烧过程。以实验为基础，建立了煤的碳燃烧模型，变工况数值模拟了煤的碳燃烧过程，揭示了煤不同条件下的单颗粒碳燃烧特性。     

氢气纯度分析方法准确性的探讨

ONACCURACYOFANALYSISOFOFHYDROGEN1前言我公司目前应用的氢气纯度分析方法有两种,一种是爆炸反应法,另一种是焦性没食子酸吸收法。几年来,人们对两种分析方法的准确性曾有过褒贬不一的评论。这里我们也谈谈自己粗浅的观点。2爆炸法测定氢气纯度一定量的氢气样品与适量的空气之均匀混合物因反应后生成液体水而引起气体体积减少,减少的体积等于参加反应气体体积之和。其中l／3为氧气,2／3为氢气。根据氢气取样量和反应前后混气体体积之差,以及氢气在反应中的体积比例关系,可计算出样品的氢气纯度。计算公式式中：A一混…     

ANALYSIS OF RECENT MEASUREMENTS OF THE VISCOSITY OF GLASSES

Viscosity of Simple Soda-Silicate 500° to 1400°C Comparison of the results given by English with those of Washburn, Shelton and Libman, indicates a discrepancy in the absolute values of log₁₀ viscosity amounting to 0.6, those of Washburn et al., being relatively too high. If correction for this is made, the isothermal curves of log₁₀ viscosity as a function of soda content are smooth up to 50% Na₂O, showing no inflection. The observations as a function of temperature T are all represented within accidental error by an equation of the type where all three constants vary regularly with the composition. Change of Viscosity of Glass (6SiO₂, 2Na₂O) due to Molecular Substitution of CaO, MgO and Al₂O₃ for Na₂O The effect is clearly brought out by plotting (from the results of English) the change of log₁₀η due to the substitution as a function of temperature. The curves each show a sharp bend at a temperature between 840° and 1050°C, which is designated the aggregation temperature T_a. If we divide these curves by the corresponding percentage substituted, we get curves for each oxide which are straight and parallel below the aggregation temperatures, the slopes (increase of change of log₁₀η per 100°C) being −0.056 (CaO), −0.055 (MgO), −0.018 (A1₂O₃) per per cent oxide substituted. For substitution of 1/2 molecule the slopes are −0.325 (CaO), −0.23 (MgO) and −0.18 (Al₂O₃) per 100°. At the aggregation temperature the change of log₁₀η per per cent is a minimum, 0.03 to 0.06 for CaO, 0.12 for MgO, 0.07 for Al₂O₃. Evidence of Aggregation in Glasses, from viscosity Measurements The sharp bends in the plots of change of log₁₀η due to substitution of an oxide for Na₂O, suggest the beginning of molecular aggregation at these temperatures. These aggregation temperatures are close to the devitrification temperatures, but the effect on the viscosity curves cannot be due to actual devitrification since it does not change with time. Taking the aggregation temperatures as equal to devitrification temperatures, additional isotherms are roughly sketched into the equilibrium triangle of the system Na₂O-CaO-SiO₂. Change of Viscosity of Glass (4SiO₂, 2Na₂O) due to of Substitution of B₂O₃ for SiO₂ The change of log₁₀η (from the results of English) is plotted as a function of temperature, and also the change of log₁₀η per per cent B₂O₃. The curves are more complex than for the substitution for Na₂O.     

环氧树脂羟基值测定方法的研究

利用乙酸酐、吡啶和浓硫酸混合的乙酰化试剂测定环氧树脂中羟基值含量的方法具有操作简便、滴定终点明显和分析结果误差小等优点。     

茶多酚提取方法进展

本文综述了国内外现有茶多酚提取方法的现状以及近期的研究进展，并对其优缺点进行了评价。这将有助于中低档茶的综合利用和茶多酚的进一步开发应用。