涂料理论涂布率的测定

本文介绍了测定涂料理论涂布率的几种方法及影响因素。     

粉末喷涂系统的进展

静电粉末喷涂设备自60年代到80年代末,已经历了好几代的重大改革,使粉末喷涂系统越来越趋完美。90年代初又提出了新的要求,就是提高设备的自动化程度或喷涂系统的过程控制,以达到理想的上粉率,即把粉末涂料转换成漆膜的能力。对喷涂系统来说,Reddy 提出必须提高上粉率。提高上粉率的最有效方法是在喷枪前面没有工件     

自动静电喷涂工艺在摩托车塑料件上的应用研究

对塑料件自动静电喷涂工艺进行了实验研究，说明了塑料件形状规则度、表面积大小、导电剂涂布、中间流平时间等因素对塑料件静电喷涂效果的影响。     

二氧化硅材料在造纸中的应用

介绍了二氧化硅材料在造纸湿部配料和造纸涂料中的应用效果。试验结果表明，二氧化硅胶体应用于造纸湿部时，可以明显改善高速纸机的运行性能，提高填料的留着率，改善纸张的性能；二氧化硅粉体应用于造纸涂料时，具有良好的分散性和优良的流变性，可改善涂布纸张的表面强度，降低涂布纸张的返黄速度，改善涂布纸张的表面平滑度和光泽度。     

油漆车间面漆线喷涂设备高压问题解决与探讨

汽车涂装生产线采用高压静电喷涂已成为近年来的主流喷涂方式，高压静电喷涂有利于提高油漆吸附率，极大改善喷涂质量。结合现场喷涂设备的高压故障，简单阐述了高压产生的原因以及相应的改进措施，为高压喷涂设备的维护提供一些新思路与方法。     

尿素熔融喷涂在S—NPK复合肥生产中的运用

在转鼓喷浆涂布造粒制复合肥的基础上,增加尿素熔融喷涂补充氮养分的工艺技术.介绍了尿素熔融喷涂技术的工艺流程、特点,主要工艺指标和主要设备,以及装置改造措施和效果.利用尿素熔融喷涂生产复合肥,可显著提高生产能力,产品圆润光滑,不易结块.     

影响涂布均匀性的因素及改进措施

磁带涂布生产线经长年运行，机械磨损、电气老化，会造成涂布均匀性的明显下降，因此涂布机老化问题已成为影响磁带宽片涂布质量的重要因素。本文重点讨论了如何采取措施，来提高老涂布机的涂布均匀性。     

影响涂布均匀性的因素及改进措施

磁带涂布生产线经长年运行，机械磨损、电气老化，会造成涂布均匀性的明显下降，因此涂布机老化问题已成为影响磁带宽片涂布质量的重要因素。本文重点讨论了如何采取措施，来提高老涂布机的涂布均匀性。     

溶剂挥发速率对涂层表观的影响

本文通过不同挥发速率的溶剂及其组合对涂层表观影响的研究,解决了紫外光固化体系喷涂工艺中经常出现的针孔、点子等涂布弊病。     

影响粉末涂料上粉率因素的探讨

介绍了粉末涂料静电喷涂原理，分析了影响粉末上粉率的因素，并提出提高上粉率的工艺条件。     

空气雾化喷雾在玻璃纤维成形中的应用

阐述了原丝喷雾的工作原理及在玻璃纤维成形工艺控制中的作用。针对传统喷雾的雾化效果不理想、覆盖率低、单纤维冷却效果差、耗水量大等诸多问题,改进了喷雾方式,采用空气雾化喷雾。通过对比传统喷雾,评价涂油器处各点温度、可燃物含量、含水率变化、结皮现象等技术参数或现场情况,反映出采用空气雾化喷雾能够均匀冷却纤维、协助浸润剂涂覆、减少热辐射、减少浸润剂结皮现象,达到了良好效果。     

Fat encapsulation in spray-dried food powders

The surface composition of spray-dried sodium caseinate/lactose emulsions having different oil phases were estimated using electron spectroscopy for chemical analysis (ESCA), and the particle structure was studied using scanning electron microscopy (SEM) both before and after storage under humid conditions. After spray-drying, powders in which the oil phases consisting of fats with intermediate melting points, such as hardened coconut oil and butter fat, had the highest surface coverage of fat, approximately 34%. The powder with soybean oil as the oil phase had a surface coverage of fat of approximately 15%. The high-melting hardened rapeseed oil was almost completely encapsulated after spray-drying. After storage in a humid atmosphere, fat was released onto all the powder surfaces (surface fat after storage, between 50–65%) except for those with hardened rapeseed oil in which the fat remained encapsulated. These observations are consistent with the powder structure observed by SEM. The surface composition estimated by ESCA for spray-dried sodium caseinate/lactose-containing emulsions with different amounts of soybean oil and a constant lactose/sodium caseinate ratio showed an almost completely encapsulated oil-phase after drying. Storage of these powders in a humid atmosphere leads to a release of fat onto the powder surface even if the soybean oil content is low (1% of the dry weight). Powders made from soybean oil emulsions with sodium caseinate alone exhibit a much lower degree of encapsulation than in the system where lactose is present.     

Multiscale modeling for nanoscale surface composition of spray-dried powders: The effect of initial droplet size

The surface composition of spray-dried powders is influenced by spray drying conditions in a complex manner. Among them, precise control of the size of atomized droplets is most challenging and the droplet size affects the surface composition of dried powders. A multiscale approach that couples molecular-level packing interpretation with a continuum diffusion model was introduced recently to predict surface compositions of spray-dried monodisperse powders. In this work, the method is extended to take the droplet size distribution into account. Detailed sample calculations for the lactose–protein systems have demonstrated that not only the average size, but also the standard deviation of the size distribution of atomized droplets affect predictions significantly when the precursor solution contains a small amount of protein. Model predictions of the effects of droplet size on surface coverage of protein have been validated using published experimental data. Moreover, model-based analysis provides important insights into our understanding of the X-ray photoelectron spectroscopy measurement data on surface chemical composition.     

Influence of flame conditions on the dispersion of Pd on the flame spray-derived Pd/TiO2 nanoparticles

The Pd/TiO₂ nanoparticles containing 5 wt.% Pd were synthesized by one-step flame spray pyrolysis (FSP) under different flame conditions. As revealed by both X-ray diffraction (XRD) and transmission electron microscopy (TEM) results, the average particle sizes of Pd/TiO₂ were increased from 9.7 to 24.6 nm with increasing the precursor concentration and the feed flow rate as well as reduction of the O₂ dispersing gas during FSP synthesis. Although the BET surface area and %anatase phase content were decreased with increasing Pd/TiO₂ particle size, %Pd dispersion as determined from the amounts of CO chemisorption were higher on the larger size FSP-made Pd/TiO₂ nanoparticles. It is suggested that the shorter residence time in flame and/or the lower combustion energy (enthalpy density) resulted in more coverage of Pd surface by the formation of Ti-O groups, rendering lower CO chemisorption ability of the smaller size Pd/TiO₂.     

喷雾干燥的研究进展

介绍了国内外喷雾干燥领域的最新研究进展,阐述了喷雾冷冻干燥、超临界喷雾干燥等方面的研究结果,探讨了关于喷雾干燥过程数学模拟的研究方法和结论,总结、归纳并提出了目前国内外较新的关于喷雾干燥的研究课题和方向。     

压力喷雾干燥在聚氯化铝生产中的应用

近几年中国开始采用喷雾干燥生产高品位固体聚氯化铝，以适应国际产品的市场要求。笔者对采用压力喷雾干燥和离心喷雾干燥生产固体聚氯化铝进行了比较，通过实例介绍了压力喷雾干燥生产应用情况，并对生产影响因素和改进措施进行了论述。     

我国喷雾干燥技术研究及进展

回顾中国喷雾干燥技术的发展历史 ,总结过去三十多年在喷雾干燥技术研究开发运用中的主要成果 ,并提出了二十一世纪中国喷雾干燥技术的研究发展方向     

喷雾干燥塔的节能方法

本文简要介绍了喷雾干燥塔的使用特点,并探讨了其节能方法。     

新型氧乙炔火焰粉末多功能喷枪

阐述了ＨＶ－９０００新型氧乙炔火焰粉末多功能喷枪突出的优越性：轻便手持喷枪和车床操作运行自动喷涂,既能喷涂各种高熔点合金和陶瓷粉末,又能喷涂低熔点锌、铝、巴氏合金,及塑料、尼龙粉末;主要操作参数控制均集中设置在枪体各调节阀刻度显示;借鉴国外超音速火焰喷咀使粒子飞行速度比常规氧乙炔火焰喷涂提高４～５倍;采用喷咀燃烧器内燃气混合方式避免回火,保证喷枪长时间连续稳定工作;喷枪上粉斗采用双孔位送粉开关,可迅速方便调节不同送粉量,并可选择多种气体送粉,以及外接送粉器的多功能供粉结构;该喷枪具有５种独特喷咀,可获得不同用途的高质量涂层。     

RECENT PROGRESS OF SPRAY DRYING IN CHINA

The development of spray drying technique during past 10 years in China is reviewed. Main achievements in research, development and utilization of three types of atomization are described and summarized. General trend of spray drying research and development in 21st century is forecasted.