NR—BR／EPDM并用胶硫化的研究

研究了天然橡胶（ＮＲ）、顺丁橡胶（ＢＲ）与三元乙丙橡胶（ＥＰＤＭ）并用胶的硫化条件和经活性剂ＤＳ处理的ＥＰＤＭ用量对并用胶性能的影响。试验结果表明，采用ＮＲ－ＢＲ／ＥＰＤＭ（７０／３０，质量比）并用胶１００份，碳黑６０份、氧化锌４份、活性剂ＤＳ２．５份、促进剂２．５份、硫化剂２．５份、其他助剂１０份的加工配方，可以制得综合性能好的单用胶，它具有强度高、弹性高、拉伸疲劳性及粘接性好、耐老化和耐臭氧性     

EPDM熔融接枝甲基丙烯酸缩水甘油酯及其与NR动态硫化共混物的性能

研究了三元乙丙橡胶熔融接枝甲基丙烯酸缩水甘油酯（ＧＭＡ）的接枝反应温度、过氧化二异丙苯（ＤＣＰ）及ＧＩＭ用量对ＥＰＤＭ－ｇ－ＧＭＡ／ＮＲ动态硫化共混物力学性能的影响。结果表明：与直接静硫化胶相比,动态硫化胶的拉伸强度提高了４８．２％;接枝反应温度８为１６０℃、ＤＣＰ用量为０．３份、ＧＭＡ用量为３￣５份时,动态硫化共混物的力学性能较好。另外红外光谱测试结果表明,在ＥＰＤＭ上已成功接枝了ＧＭＡ。     

CR—MMA—CEVA接枝共聚物的制备及其粘合性

以甲苯／丁酮为溶剂，过氧化苯甲酰为引发剂，于９０±１℃下制备了氯丁橡胶－甲基丙烯酸甲酯－（氯化乙烯－乙酸乙烯酯）（ＣＲ－ＭＭＡ－ＣＥＶＡ）接枝共聚物。当ＣＥＶＡ用量为２－８份（按ＣＲ１００份计），ＭＭＡ转化率约３７．８３％时，接枝共聚物胶液用于粘合聚氯乙烯布基革，静置４ｄ时的１８０°剥离强度为５．４４ｋＮ／ｍ，超过优级品指标（３．５ｋＮ／ｍ）。     

CR－MMA－CEVA接枝共聚物的制备及其粘合性

以甲苯／丁酮为溶剂，过氧化苯甲酰为引发剂，于９０±１℃下制备了氯丁橡胶－甲基丙烯酸甲酯－（氯化乙烯－乙酸乙烯酯）（ＣＲ－ＭＭＡ－ＣＥＶＡ）接枝共聚物。当ＣＥＶＡ用量为２～８份（按ＣＲ１００份计），ＭＭＡ转化率约３７．８３％时，接枝共聚物胶液用于粘合聚氯乙烯布基革，静置４ｄ时的１８０°剥离强度为５．４４ｋＮ／ｍ，超过优级品指标（３．５ｋＮ／ｍ）。     

LDPE接枝马来酸锌离聚物对PP／PA6共混体系相容性的影响

采用ＳＥＭ和动态粘弹谱研究了不同接枝率的ＬＤＰＥ接枝马来酸锌离聚物（ＬＤＰＥ－ｇ－ＭＡＺｎ）对ＰＰ／ＰＡ６共混体系相容性的影响。ＬＤＰＥ－ｇ－ＭＡＺｎ采用熔融法合成,所制样品接枝率分别为１．５％（质量,下同）、４．５％和５．４％。研究结果表明,ＬＤＰＥ－ｇ－ＭＡＺｎ能有效地改善ＰＰ／ＰＡ６共混物的相容性,其相容性随离聚物接枝率的提高而增强。在ＰＰ（９０）／ＰＡ（１０）体系中,加入离聚物后分散相（ＰＡ６）更均匀、粒子尺寸更小,而且随着离聚物接枝率的提高,ＰＡ６颗粒的粒径就越小,分散越匀;在ＰＰ（５０）／ＰＡ（５０）的体系中,离聚物的加入使两相互相贯穿,在动态粘弹谱上表现出Ｔｇ相互靠近,熔断温度有所提高。     

不同共混比Ln—BR／NR的性能

研究了稀土顺丁橡胶（Ｌｎ－ＢＲ）与天然橡胶（ＮＲ）以不同比例共混后生胶、混炼胶和硫化胶的性能，并与相同条件下的镍系顺丁橡胶（Ｎｉ－ＢＲ）／ＮＲ共混胶的性能进行了对比，结果表明，共混胶随Ｌｎ－ＢＲ用量的增大，ＭＬ＾１００℃１＋４降低，工艺行为良好，硫化胶力学性能、磨耗、湿滑指数和生热值下降，并且Ｌｎ－ＢＲ／ＮＲ硫化胶的抗湿滑性和动态疲劳性均优于Ｎｉ－ＢＲ／ＮＲ硫化胶。     

NBR/Zn(MAA)2合金性能与结构的关系

将自制的甲基丙烯酸锌「（Ｚｎ（ＭＡＡ）２」与丁腈胶（ＮＢＲ）共混,采用就地反应的方法制德了ＮＢＲ／Ｚｎ（ＭＡＡ）２合金,研究了不同Ｚｎ（ＭＡＡ）２用量时ＮＢＲ／Ｚｎ（ＭＡＡ）２的力学性能。结果表明,随着Ｚｎ（ＭＡＡ）２用量的增大,合金铁力学性能显著提高,以Ｚｎ（ＭＡＡ）２用量为４０￣６０份（质量份）时为最佳。傅晨叶变换红外光谱和扫描电镜分析表明,在硫化过程中,Ｚｎ（ＭＡＡ）２与ＮＢＲ发生了接枝和共     

天然高分子吸附剂研究

研究了羧甲基化的交联壳聚糖树脂（ＡＣ－ＣＴＳ）对Ｚｎ（Ⅱ）Ｐｂ（Ⅱ）离子的吸附性能。结果表明，该树脂对Ｐｂ２＋比对Ｚｎ２＋具有更强的吸附选择性，其对Ｐｂ２＋和Ｚｎ２＋的吸附容量分别为６６０．９７和１７２．００ｍｇ·ｇ－１；其ＫＰｂ２＋／Ｚｎ２＋＝３．８４；其吸附的最佳ｐＨ值分别为５．４和４．０；在低浓度时，ＡＣ－ＣＴＳ对两种离子的吸附率均可达１００％。     

PVC／SBR热塑性弹性体的研制

以ＡＢＳ、氯丁橡胶（ＣＲ）、马来酸酐（ＭＡ）接枝ＳＢＲ（ＳＢＲ－ＭＡ）作增容剂对ＰＶＣ／ＳＢＲ的共混比、增容剂、增塑剂用量做了优化选择。同时对动态硫化ＰＶＣ／ＳＢＲ的硫化体系、硫化工艺条件进行了探讨,并比较了动态硫化对共混体性能的影响。结果表明：ＰＶＣ／ＳＢＲ为８０／２０,增容剂ＡＢＳ／ＳＢＲ－ＭＡ为５／５时,选用半有效硫化体系,１６５℃下动态硫化６ｍｉｎ,共混物综合性能最佳     

过氧化物动态硫化的NBR/POM共混物性能的研究

采用过氧化物硫化体系用动态硫化方法制备了丁腈橡胶／聚甲醛（ＮＢＲ／ＰＯＭ）热塑性弹性体。研究了硫化体系、橡塑比对共混物性能的影响。实验结果表明．采用２，５－二甲基－２，５－双（叔丁基过氧基）己烷硫化体系硫化效果较好．共混物的综合性能优异；随着ＰＯＭ用量增加．共混物的拉伸强度略有增加，表观粘度降低，加工性能变好，电绝缘性能、老化性能和耐油性能均得到明显改善。     

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。