全钢载重子午线轮胎激光无损检测气泡的产生原因及解决措施

分析全钢载重子午线轮胎激光无损检测气泡的产生原因,并提出相应的解决措施。轮胎激光无损检测气泡主要在半成品部件贴合和胎面辊压过程中产生。通过严格控制半成品部件存放条件、提高半成品部件的粘合性能、改进胎面压辊形状、确定适合的胎面辊压工艺参数等措施,成品轮胎的激光无损检测气泡产生率从0.136 5%减小至0.044 3%。     

全钢载重子午线轮胎胎圈气泡的产生原因及改进措施

分析全钢载重子午线轮胎胎圈气泡的产生原因并提出相应改进措施。施工设计及半成品尺寸不当、排气线完整性差、成型贴合压辊位置不合理及硫化模具钢圈排气线不通等均会导致胎圈气泡缺陷。经过优化施工设计、增加胎侧及加强层刺孔工艺、规范半成品尺寸过渡及成型辊压等措施能够有效减少胎圈气泡的产生,提高轮胎合格率。     

全钢载重子午线轮胎胎肩气泡的原因分析及解决措施

分析全钢载重子午线轮胎胎肩气泡的产生原因,并提出相应解决措施.通过采取严格控制挤出排胶温度以及压延供胶温度和辊温、确保半成品部件表面充分干燥、修正挤出口型、严格控制半成品停放时间、定期检查成型机精度、合理设置后压辊在肩部的摆转位置和停顿时间、定期检查维护硫化管路、合理设定硫化条件以及硫化前用细针刺胎坯胎肩部位等措施,有效减小了全钢载重子午线轮胎胎肩气泡的发生率.     

全钢载重子午线轮胎胎圈气泡的原因分析及解决措施

分析全钢载重子午线轮胎胎圈气泡产生的原因,并提出相应的解决措施。结果表明:通过严格控制半成品质量,改善成型工艺和设备,调整内衬层宽度、级差、边厚和加强层封口胶片定位等,使各部件端点尽量避开胎圈底部,材料分布合理化,取得了较为明显的效果,有效降低了胎圈气泡的发生率。     

全钢载重子午线轮胎胎圈大边原因分析及解决措施

分析全钢载重子午线轮胎胎圈部位出现大边的原因,并提出相应的解决措施。优化胎圈部位的材料分布、钢丝圈和半成品部件的形状及尺寸设计、成型鼓扇形块压力,控制硫化机械手对中度和张开度精度,改进成型胶圈和模具钢圈的形状设计,可减少胎圈大边的发生,使全钢载重子午线轮胎胎圈大边发生率由6%降到了1.5%。     

全钢载重子午线轮胎胎肩气泡产生原因及解决措施

对全钢载重子午线轮胎胎肩气泡产生原因进行分析,并提出相应的解决措施。从结构设计、半成品部件和成型方面分析胎肩气泡产生原因,通过采取重新设计胎面和垫胶尺寸,调整带束层宽度;严格控制车间温度和湿度,保证物料存放条件,增大胎面基部胶宽度;根据不同胎面调整压合压力,校正后压辊精度等措施,有效解决了全钢载重子午线轮胎胎肩气泡问题。通过加强现场工艺监控措施,明显减小了胎肩气泡发生几率。     

全钢载重子午线轮胎质量缺陷产生原因及解决措施

从操作及工艺控制方面分析全钢载重子午线轮胎经常出现的胎里露线、胎圈露钢丝、胎体劈缝、胎里气泡、胎里窝气、胎趾圆角和胎侧欠硫外观质量缺陷的产生原因,并从设备改进、产品设计和工艺管理方面提出相应的解决措施.严格控制半成品尺寸、成型和硫化定型操作等可保证全钢载重子午线轮胎质量和生产效益.     

全钢载重子午线轮胎全息气泡原因分析及解决措施

介绍全钢载重子午线轮胎全息气泡的类型,对其产生原因进行分析,并提出解决措施。全息气泡主要分为冠部和肩部气泡,通过采取严格控制半成品部件尺寸和气孔率、确保半成品的粘合性能、合理设置后压辊形状和轨迹、合理设定硫化时间和温度以及定期检查硫化管路等措施,使全钢载重子午线轮胎全息气泡不合格率从0．8％降至0．2％以下。     

全钢载重子午线轮胎胎冠气泡的解决措施

分析全钢载重子午线轮胎胎冠气泡的特征和形成原因,并提出排除气泡的措施.通过采取合理设定带束层宽度,保证带束层级差在15 mm以上,合理设计胎面和胎肩垫胶断面形状,合理选取成型胎面压辊形状、成型压力和胎面存放方式,取消第3和第4层带束层包边,改善半成品表面粘性以及胎肩刺孔等措施,有效减少了全钢载重子午线轮胎胎冠气泡缺陷.     

提高全钢载重子午线轮胎动平衡性能的措施

以提高全钢载重子午线轮胎动平衡性能为中心,介绍解决轮胎几何尺寸偏差大(主要为轮胎径向和侧向尺寸偏差大)和质量不均匀的措施。通过严格控制挤出机机头各部件和硫化模具的加工精度。保证胎面等半成品的尺寸公差符合要求,定时校验成型机精度,严格执行成型操作规范等措施,有效提高了全钢载重子午线轮胎的动平衡性能。     

乙苯,苯乙烯的生产及合成乙苯,苯乙烯催化剂的研究进展

苯乙烯是重要的石油化工原料。本文介绍了国内外苯乙烯生产的发展概况，合成乙苯，苯乙烯所用的催化剂种类，并就苯乙烯生产及催化剂的发展趋势提出了自己的观点。     

Synthesis and characterization of homopolymers and copolymers of various acrylates and acrylonitrile

Various homopolymers and copolymers of methyl acrylate, ethyl acrylate, butyl acrylate, and acrylonitrile in different feed ratios were synthesized. These were characterized by IR, ¹³C-NMR, DSC, DTA, and TGA. Spectroscopic characterization helped in differentiating copolymers of different mol ratios. Thermal analysis revealed different degradation patterns for homopolymers and copolymers. The temperature and energy changes associated with various phase transitions were dependent on the chemical composition of homo- and copolymers, as expected. © 1993 John Wiley & Sons, Inc.     

生物质气化及生物质与煤共气化技术的研发与应用

总结了生物质原料的特点及生物质单独气化的缺点;介绍了国内外生物质气化技术及生物质与煤共气化技术的研发与应用现状;分析了在此领域国内外的发展趋势与前景;概括了开展生物质与煤共气化技术研发的意义。     

Electronic structures and reactivities of monometallic and bimetallic clusters of Au and Cu

The variation of the Au 4f binding energy of Au clusters with the cluster size has been established by measuring the binding energies of clusters whose size distributions were independently determined by HREM and STM. The binding energy increases significantly when the cluster size is less than 2 nm. Au-Cu bimetallic clusters of the composition Cu₃Au have been deposited for the first time on carbon substrates. The shifts in the core level binding energies of the bimetallic clusters show the effect of alloying in the case of large clusters, but show effects of both alloying and cluster size in the case of the small clusters. The interaction of CO with Cu₃Au clusters is stronger than with a bulk Cu metal. The interaction of CO with small Cu clusters also seems to be stronger than with bulk Cu or with large Cu clusters.     

钾盐资源及钾肥供需情况分析及预测

阐述了国内外钾盐资源及钾肥生产现状,对国内外钾盐的供需形势进行了分析及预测,从资源、原材料、国际市场三方面提出了解决我国钾盐短缺的措施。     

Kinetics and Mechanism of Oxidation of Mono- and Polyacetals

Abstract

Kinetics and mechanisms of oxidation of 6 acetals by molecular oxygen and ozone in liquid phase have been studied. Reaction with molecular oxygen (70°C, 15–16 hr) leads to the formation monoethers of the corresponding glycols with 68–90% selectivity. Salts of metals and complexes with crown-ethers have increased the reaction rate significally. Ozone have reacted with acetals with formation similar products. The mechanisms of intermediate stages have been proposed.     

Comparison of the Adhesion and Cohesion of Triblock and Random Copolymers of Styrene and Butadiene

A substantially greater detachment energy is required to strip a polyethylene tereph-thalate (Mylar) film from a styrene-butadiene-styrene (SBS) triblock copolymer compared to that for peeling from a random styrene-butadiene (SBR) copolymer. This is true even though the intrinsic interaction between the Mylar and each elastomer is expected to be similar because of their virtually identical chemical composition. It is proposed that this difference in peel strength (between the SBS and SBR) is a consequence of the much higher dissipative capacity of the former elastomer. Another manifestation of this is the higher cohesive tear strength of the SBS compared to the SBR. Extents of energy dissipation within each elastomer during detachment of the Mylar adherend are consistent with the hypothesis that the average maximum stress experience before detachment is some similar fraction of each elastomer's tensile strength.     

Wetting properties of homopolymers and copolymers of pentafluorostyrene and methylacrylate and homopolymer blends

Polypentafluorostyrene (PPFS), polymethylacrylate (PMA), and poly(pentafluorostyrene-co-methylacrylate), poly(PFS-co-MA) were prepared and the wetting characteristics of polymer blends of PPFS and PMA were compared with that of poly(PFS-co-MA) via contact angle measurements. The critical surface tension of polypentafluorostyrene was found to be 22.6 dyne/cm, which is comparable to the value reported for polytrifluoroethylene (22 dyne/cm). The critical surface tension of poly(PFS-co-MA) is not linearly related to its composition. The polymer blends of PPFS and PMA exhibit significant surface enrichment of the fluoropolymer. The harmonic-mean method¹ was employed to determine surface tensions of these polymers and many known polymers. It is found that the method produces useful surface tension data provided the contact angle values are derived from testing liquids of dissimilar polarity.     

责任和责任心的涵义与结构

责任是人应主动承担的角色义务和对其因过失所造成后果应承担的责罚.有两层涵义:一是义务;二是后果.责任心是个体自觉做好分内事务和履行道德义务的心理倾向,是个性心理品质成分中自我特征维度上的重要内容.责任心具有两个方面的涵义:一是角色分内职责;二是角色道德义务.责任心是一种通过责任认知、责任个性和责任适应的动态形式表现出来的静态品质,责任心是责任心过程结构与责任心关系结构相互制约、相互影响的统一体.     

二甲基二烯丙基氯化铵和丙烯酰胺的合成及应用

用复合引发体系(过硫酸盐-偶氮类引发剂)和脂肪胺类氧化还原体系引发,在实验室获得了单体转化率≥98%,特性粘数高于13.6 dL/g的阳离子共聚物PDA,探讨了控制聚合物分子量的影响因素.