用于玻璃钢的无碱、中碱玻璃布在沸水中的强度变化

玻璃纤维化学成份是影响玻璃钢性能、质量、价格的重要因素之一。在国际上,作为玻璃钢使用的玻璃纤维增强材料,几乎全部采用E玻璃纤维(无碱玻璃)。我国虽然有无碱、中碱、高碱、高强、高模量等成分玻璃,但作为玻璃钢用增强材料是以中碱、无碱成份为主。近年来,我国采用中碱纤维作为增强材料约占玻璃钢用玻璃纤维量的80％以上(不包括电绝缘材料),与世界上其他国家比较,采用中碱成份纤维较多。     

关于提高中碱池窑拉丝纤维成形效率的讨论

分析了中碱玻璃纤维的料性并研究了影响中碱玻璃纤维成形效率的主要因素；回顾了中碱玻璃成分改性的研究成果并介绍了中碱玻纤成分改性的进展；针对中碱池窑采用的玻璃成分、纤维成形工艺等环节提出了一些改进建议。     

一种高碱玻璃纤维的耐水性研究

耐水性差是高碱玻璃纤维的主要缺陷,为此通过以SiO_2和Na_2O为主要成分的高碱玻璃纤维耐水性的实验分析,研究了纤维中R_2O质量分数与纤维耐水性关系,同时研究了适量引入其他氧化物对高碱纤维耐水性能的影响,为高碱玻璃纤维的生产应用提供一定价值的参考。     

SiO_2气凝胶-玻璃纤维复合隔热材料中玻璃纤维分散工艺研究

为了提高SiO_2气凝胶-玻璃纤维复合材料的力学性能,研究了不同溶剂(分别为环己烷、正己烷、乙醇、丙酮)、不同分散方式(分别为行星球磨分散、超声分散和机械搅拌分散)和分散时间(10～40 min不等)对短切无碱玻璃纤维束分散效果的影响,以确定短切无碱玻璃纤维束的最佳分散工艺;在此基础上,按SiO_2气凝胶粉和短切无碱玻璃纤维束质量比为90∶10配料,添加一定量的氧化锌遮光剂和酚醛树脂结合剂,分别在短切无碱玻璃纤维束中直接加入和预分散后加入两种条件下制成SiO_2气凝胶-玻璃纤维复合材料试样,然后检测试样的常温耐压强度以及在不同热面温度(分别为300、400、500和600℃)下的热导率。结果表明:1)短切无碱玻璃纤维束的最佳分散工艺是以乙醇为溶剂,机械搅拌30 min; 2)短切无碱玻璃纤维束预分散与否对SiO_2气凝胶-玻璃纤维复合材料的热导率影响较小,但短切无碱玻璃纤维束预分散后加入有利于提高复合材料的常温耐压强度。     

FRP制品白丝形成原因分析

阐述FRP制品白丝的形成过程和造成的质量影响;通过对无碱玻纤池窑拉丝生产线主要质量控制环节的研究,分析了无碱玻璃纤维FRP制品白丝现象的形成原因;总结了不同原因形成FRP制品白丝的规律,为玻璃纤维生产中相关质量控制提供了一些方法。     

ECR和中碱玻璃纤维的耐酸性试验

主要研究了ECR耐腐蚀玻璃纤维和中碱玻璃纤维在酸液腐蚀环境下的单丝强度及形貌特征。根据实验与纤维观察结果,对ECR玻璃纤维与中碱玻璃纤维在所给环境条件下的力学性能、耐酸性进行综合对比,分析不同增强玻璃纤维在酸性腐蚀环境下的破坏机理,评价其应用范围。研究结果表明中碱玻璃纤维耐酸性较好,但其强度不高;ECR玻璃纤维的强度较高且耐酸性也较好。故ECR玻璃纤维适用于对强度和耐酸性均有较高要求的环境中;中碱玻璃纤维适用于对强度要求低但对耐酸性有一定要求的环境中。     

中碱玻璃纤维表面析碱与强度关系研究

本文通过中碱、无碱玻璃纤维单丝、原丝和方格布水侵蚀下的浸出动力学研究,强度变化研究以及偶联剂处理效果和对玻璃钢强度影响的研究,从而对我国大量工业生产的中碱玻璃纤维的耐水性能、强度性能有了更深刻的认识和评价,为中碱纤维的扩大应用和提高中碱玻璃钢的性能,提供更多的数据资料.     

建筑用玻璃纤维网布性能的研究

从对无碱、中碱和耐碱玻璃基本性能的试验研究出发,阐述了玻璃成分对玻璃纤维力学性能、化学稳定性和脆性的影响。结合建筑外墙外保温工程的要求,对中碱和耐碱玻璃纤维网布拉伸断裂强度、耐碱性、断裂伸长率和涂覆量进行了试验研究。通过对试验结果的分析,提出了无碱和中碱玻璃纤维网布的拉伸强度大于耐碱玻璃纤维网布约30%左右;经涂覆处理的中碱玻璃纤维网布用于聚合物基的外墙外保温系统是可靠的;耐碱玻璃纤维由于本身具有一定的耐碱性,再经过涂覆处理,增加了表面保护层,耐强碱的能力优于中碱玻璃纤维网布的观点。     

中碱5~#玻璃球结石岩相分析

中碱5~#玻璃球(其化学成分见表)是坩埚法生产玻璃纤维的原料,其质量的好坏对玻璃纤维生产影响较大。特别是结石缺陷的出现破坏了玻璃球均匀性,导致其机械强度、热稳定性和化学稳定性的降低。而且是造成拉丝断头、飞丝(成束的突然断丝)的     

玻璃纤维拉丝池窑配合料设备研制的进展

玻璃纤维池窑拉丝生产线配合料的制备中,原料是形成优质玻璃液的基础,因此可以说配合料的稳定性、均匀性和准确性对玻璃纤维的质量起着决定的作用.生产实践证明:组分和粒度均匀的配合料,不但能强化玻璃液的熔化和澄清过程,而且还能减少或消除影响玻璃质量的各种弊病.所以认真拟定玻璃纤维原料的成分和选择玻璃纤维的种类和化学性质:严格控制进厂原料化学成分、粒度和水份;做好原料的分堆、存放、加工、称量、混合、输送是优质配合料制备不可缺少的手段,这也是做好玻璃纤维池窑配合料的基本任务.     

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…     

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.     

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.     

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.     

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。     

几种针状焦性能对比

针状焦分石油系和煤系两大类,这主要取决于针状焦的原料来源。在同一系列中由于原料不同和工艺条件不同 ,针状焦的各自性能也不相同。针状焦是生产超高功率石墨电极和高功率石墨电极的主要原料 ,针状焦的性能对石墨电极的质量有至关重要的影响。所以对针状焦性能以及其对石墨电极质量影响的研究十分必要的。以下是常用的几种进口针状焦和国产针状焦的性能对比。１原料性能分析对比原料试样包括４种针状焦 ,其中两种为进口针状焦：三菱针状焦和新日化针状焦;另两种为国产针状焦：鞍山针状焦和锦州针状焦。其中除锦州针状焦是石油系针状焦外…     

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。     

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。     

聚酰亚胺的合成法

本文评述了缩聚型聚酰亚胺的主要合成方法和近年来国际上在合成中所做的探索。