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本文提供对重油中的正己烷、甲苯不溶物含量的一种简易、连续测定法,该法可测定不溶物含量范围从0~100%,测定结果符合A STM D 91方法和A STM D 2317方法,新建的正己烷不溶物、甲苯不溶物的方法重复性好,设备简单、操作方便,采用一次性取样,能比较快速地完成两种溶剂的不溶物测定,有利于满足监控进厂重油的质量要求。 相似文献
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在2003年第12期<水泥>杂志上,我们对欧洲标准BS EN 196-21:1989中低不溶物水泥(不溶物含量<3.0%的水泥)碱含量的测定方法作了简单介绍.这种方法结果准确,简单快捷,节约成本,是一种非常实用的方法.我们对于不溶物含量较高的水泥以及铁粉、黏土等水泥原材料也进行了对比试验.试验结果表明,这种方法可以用于不溶物含量较高的水泥和水泥原材料中碱含量的测定. 相似文献
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本文从理论和实验上,用大量的数据说明:用工业酒精作溶剂,测定松香钙皂中不溶物的含量,不仅溶解性好、毒性小、安全可靠,操作简单;而且测定结果准确(误差≤1%),重现性好,是一种较理想的测定松香钙皂中不溶物含量的方法。 相似文献
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作为橡胶质量控制指标,国际上和行业内均采用室温甲苯溶解不溶物含量来表征凝胶含量。以甲苯为溶剂,采用溶剂溶解分级的方法,考察了溶解分级时间、温度等条件对反式-丁二烯-异戊二烯共聚橡胶(TBIR)中甲苯不溶物含量的影响。进一步采用凝胶渗透色谱仪(GPC)对分级得到的可溶物级份进行了分子量及其分布的表征,结果表明:在相同的溶解时间下,随着溶解温度的升高,TBIR的不溶物含量逐渐降低,80℃时不溶物含量降至1.59%;随着溶解时间的延长,不溶物含量逐渐降低,8~24 h达到稳定。可溶物的分子量随溶解分级温度的升高略增大,分布变窄;确定了TBIR凝胶含量测定条件。 相似文献
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针对在试验过程中发现煤沥青中喹啉不溶物分析结果偏高的现象,根据煤沥青中甲苯不溶物的测定原理,找到造成这种现象的原因,然后从不同的角度进行试验,最终摸索出一套分析煤沥青中喹啉不溶物含量的简单、经济、可行的方法。 相似文献
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宋欣茹 《中国洗涤用品工业》2015,(4):79-82
洗涤剂总活性物含量的测定(A法)中,需要先定量乙醇不溶物测定出氯化钠的含量,继而得出产品中总活性物的含量。鉴于洁厕块多为带色产品,考虑到产品颜色对硝酸银滴定法测定氯化钠含量的影响,特对洁厕块中氯化钠含量的测定方法进行了研究,以便更好地利用该法测定出含有氯化钠洁厕块的总活性物的含量。 相似文献
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采用现行国家标准GB/T 20211-2006<烟花爆竹用钛粉>测定三酸不溶物(硫酸、盐酸、硝酸)含量,结果测定值为200%~300%,而标准规定值为0.1%~1%,因而原标准方法测得的结果并不是钛粉中的杂质含量,本文通过多次实验,找到了原标准的失误之处以及测定烟花爆竹用钛粉中三酸不溶物含量的方法,并从理论上进行了解释. 相似文献
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我厂3号回转窑(Φ4m×60m)生产线在1996年年底由SP窑(产量912t/d)改为NSP窑(产量1320t/d),预分解系统为四级旋风预热器带离线式分解炉 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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The miscibility of various amorphous polybutadienes with mixed microstructures of 1,4 addition units (cis, 1,4 and trans 1,4) and 1,2 addition units have been investigated. The studies here involved optical transparency, differential scanning calorimetry, and small angle light scattering. It was found that a 90 percent (cis) 1, 4 addition polybutadiene was immiscible with high (91 percent) 1,2 addition polybutadiene. Reduction of the 1,2 content to 71 percent induced an upper critical solution temperature (UCST) with the cis 1,4 polymer. Polybutadienes with 50 percent and 10 percent 1,2 contents were miscible above the crystalline melting temperature of the cis 1,4 polybutadiene. Immiscibility of the 91 percent 1,2 addition polymer was also found with a 10 percent 1,2 polybutadiene. The latter polymer also exhibits an UCST with the 71 percent 1,2 polymer. The results are used to interpret the characteristics of blends of polybutadienes of varying microstructure. 相似文献
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以F类粉煤灰为例,详细介绍了测定粉煤灰中烧失量的步骤、计算数学模型、影响测量不确定度的因素以及各项测量不确定度分量评定,人员、设备、材料、方法、环境都是影响测量不确定的因素。 相似文献
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The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003 相似文献