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研究了马尾松预水解硫酸盐(KP)浆氧脱木素工艺,并对马尾松预水解KP浆氧脱木素与马尾松KP浆氧脱木素进行了比较,对马尾松预水解KP浆氧脱木素的机理进行了初步探讨.得出马尾松预水解KP浆氧脱木素最优工艺条件为:用碱量3%,温度100℃,时间60 min,氧压0.5 ~0.6MPa,MgsO4用量0 2%;马尾松预水解KP浆氧脱木素率与预水解保温时间呈线性增长关系,其氧脱木素率高于马尾松KP浆,黏度降低率低于马尾松KP浆;经过红外光谱图分析,得出氧脱木素时马尾松预水解KP浆愈疮木基脱除量大于马尾松KP浆,马尾松预水解KP浆氧脱木素前后碳水化合物吸收峰相对强度减弱程度较马尾松KP浆小. 相似文献
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对落叶松化学浆的特性进行了研究.研究结果表明,在纸浆卡伯值相近时,AS-AQ法浆的得率比KP法高约2个百分点,浆的粘度高约20%,易打浆、易漂白.在相同的打浆度下,AS-AQ浆的Z向强度明显高于KP浆,其由高到低的顺序是:未漂AS-AQ浆,漂白AS-AQ浆,漂白KP浆,未漂KP浆.受纤维结合力影响较大的抗张强度、耐破强度和耐折度都符合这一规律.AS-AQ浆的零距裂断长也高于KP浆.相同打浆度下的未漂KP浆的撕裂强度高于AS-AQ浆,但在相同抗张强度下,未漂腾加浆的撕裂强度远高于未漂KP浆.漂白AS-AQ浆的撕裂强度与KP浆相当. 相似文献
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对KP法浆厂臭气的成分及性质做了简单介绍,重点举例对KP法浆厂臭气CNCG、DNCG和SOG的收集做了详细分析,并对各种臭气的输送、处理方法做了阐述。无论是从经济效益还是从环境效益考虑,KP法浆厂臭气的收集与处理都是十分必要的。 相似文献
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The effects on the conditions of flow of the surface and configurational properties of the fibres in a compressible porous layer are discussed. The characteristics of a layer of wool are evaluated, and its compressibility is determined. It is shown that, when a liquid of initial uniform pressure flows through a compressible porous medium, the pressure gradient within the medium increases with the distance of flow. The resulting pressure drop is found to depend on a function of the ratio of the downstream to the upstream porosity of the compressible medium. Experimental results are reported for permeable flow through various layers of loose wool; these indicate that, when the flow is disturbed turbulent, the pressure drop through the layers is proportional to the square of the filter velocity. This result is not readily apparent from the graphs of pressure drop against filter velocity because of the compressibility of the fibres. 相似文献
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为提高空纱管安装效率,分析集体落纱细纱机特点,介绍了锭子杆盘结构型式,说明目前国内铝杆锭子多采用支持器弹簧加支持器帽的结构,虽能基本满足集体自动落纱细纱机的生产需要,但仍存在机械手安装空纱管时动作较多、动作精度不高、且易撞到锭子问题,易对锭子造成损坏并缩短锭子使用寿命的缺陷,重点对新设计的快速安装纱管的铝杆锭子的结构及原理进行分析,指出将弹簧支持器帽换成钢珠,可以大大缩短集体落纱细纱机机械手安装空纱管时间、降低对机械手动作精度的要求,且不损坏锭子、不影响锭子使用寿命,实现了节能降耗、安装效率高的目的。 相似文献
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阐述棉纺牵伸胶辊、胶圈的应用技术和牵伸原理,重点探讨了胶辊、胶圈的牵伸工艺特性及其合理配置、胶辊制作、周期管理、质量管理、使用管理、产品缺陷与其机械波分析、纺纱环境和挡车工操作水平对纺纱性能的影响,提出胶辊、胶圈有关机件的质量要求等。 相似文献
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通过回顾高校宝石及材料工艺学专业的创建历程,深入探讨了该专业未来发展所面临的、深层次的理论问题,即学科属性与文化背景,学科构成与知识内涵,学科方向与实践定位,学科任务与社会功能。在此基础上,建立了多层次技术教育的社会功能模型,由此推断:高校中的宝石及材料工艺学专业属于多层次技术教育中的高等职业技术教育。同时,还构建了该专业的技术教育的社会功能模型和学科构成模型,进一步确立了该专业的社会实践定位。 相似文献
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An account is given of a study of the effect of the amount of activating agent, the temperature, the catalyst, and the diluents used in the acetylation of cotton with perchloric acid as catalyst. Sulphuric acid was compared with perchloric acid as a catalyst. The effects of traces of water, the amount of acetyl chloride, and the rate of acetylation were studied in the acetylation of cotton with acetyl chloride and pyridine. The conditions in all cases were such that the acetylated cotton retained its fibrous form. 相似文献
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赛络纺纱钢领、钢丝圈的选配实践 总被引:1,自引:1,他引:0
为了提高赛络纺纱成纱质量,减少细纱断头,从钢领、钢丝圈的种类,卷绕过程中对纺纱的影响及其运动配合等诸多因素出发,论述了钢领、钢丝圈的选配原则,重点阐述了赛络纺纱钢丝圈运动形态的变化及钢领、钢丝圈的选配要求,通过纯棉、非棉纤维纺纱的选配实践,指出赛络纺纱线毛羽少,结构紧密,应根据纺纱纤维性能和纺纱特点,以纱线通道通畅降毛羽、运行平稳少断头、散热良好延长使用寿命为原则对钢领、钢丝圈进行选配。 相似文献
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为了倡导高速轧机的改造设计和新型轧机的创新设计,实现轧制时借助张力掌控坯片的宽展和总高余量,从金属针布高速轧机制片的典型案例入手,介绍了同步张力调节装置结构特点,通过对浮动张紧轮进行受力分析,导出了坯片张力与张紧轮浮动升力、浮动位置、坯片夹角之间的力学关系,展现了张紧轮在不同浮动位置及不同浮动升力条件下坯片张力的巨大差异;通过坯片张力对坯片轧制变形区材料流动影响的分析,强调控制坯片张力在高速轧制片中的重要性;针对原同步张力调节装置缺陷,设计出大垂距小夹角弹压可调试和大垂距小夹角重锤可调试两种新型张力调节装置。指出:轧制中坯片张力显著影响着变形效果;实际轧制中张力控制对提高轧机开台率、节约主材,降低成本、提高坯片质量有重要作用;原有轧机的改造和新型轧机的设计值得关注及研讨。 相似文献
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This paper reports solubility data and measurements of viscosity of the saturated aqueous solutions of sucrose, maltitol, and trehalose. Likewise, the metastable zone width and velocity of nucleation of the three disaccharides are compared. The narrowest metastable zone is observed for maltitol and the largest for trehalose. Such behaviour is due to a higher affinity of trehalose for water. Moreover, the crystallisation of anhydrous disaccharides in aqueous solution necessitates that hydration water be removed and evacuated from crystal integration surface to the bulk of solution to allow the growth of crystals. This step of disassociation and diffusion of hydration water proves to be the controlling step of the crystallisation process. Structural features at the origin of the differences between the three sugars are studied by FTIR spectroscopy. Modifications of frequencies and intensities of the vibrations around the glycosidic bond are interpreted in terms of conformational flexibility. Arguments like H-bond strength or conformational flexibility of the two monomers around the glycosidic oxygen were evoked as possible explanations of the behaviour of disaccharides. Likewise stability of hydration of the disaccharides is derived from the interpretation of FTIR spectra. These structural features help in interpreting the differences in crystallisation conditions and to hypothesize about the cryoprotective ability of the studied molecules. 相似文献