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141.
Arun S. Mujumdar 《Transport in Porous Media》2007,66(1-2):3-18
Over the past three decades there has been nearly exponential growth in drying R&D on a global scale. Although thermal drying
had always been the workhorse of almost all major industrial sectors, the need for and opportunities in basic as well as industrial
research became clear only after the energy crisis of the early 1970s. Although the price of oil did drop subsequently the
awareness of the significance of improving the drying operation to save energy, improve product quality as well as reduce
environmental effect remained and indeed has flourished over recent years. New drying technologies, better operational strategies
and control of industrial dryers, as well as improved and more reliable scale-up methodologies have contributed to better
cost-effectiveness and better quality dried products. Yet there is no universally or even widely applicable drying theory
on the horizon. Most mathematical models of drying remain product-equipment specific for a variety of reasons. In this paper,
we examine the role of innovation in drying in various industrial sectors, e.g. paper, wood, foods, agriculture, waste management,
etc. Progress made over the past three decades and the challenges ahead are outlined. Some areas in need of further research
are identified. Examples of intensification of innovation in dryer designs via mathematical modeling are discussed. Finally,
the need for closer interaction between academia and industry is stressed as the key to successful drying R&D in the coming
decade. 相似文献
142.
Dragana Vasiljevic Jelena Djuris Sergej Jakimenko Svetlana Ibric 《Journal of Dispersion Science and Technology》2017,38(12):1732-1737
In presented research, multiple W/O/W emulsions were developed by using experimental design method. A 24-1 fractional factorial design was performed by varying the following input parameters: primary polymeric emulsifier (PEG 30-dipolyhydroxystearate) concentration (0.8% and 2.4%), secondary polymeric emulsifier (Poloxamer 407) concentration (0.8% and 1.2%), electrolyte magnesium sulfate heptahydrate (0.08% and 0.4%) and electrolyte sodium chloride (0.08% and 0.4%). Multiple emulsions were prepared by a two-step emulsification process. Obtained emulsions were characterized with rheological measurements, conductivity and centrifugation tests. Factorial analysis revealed that the concentration of the primary emulsifier was the predominant factor influencing the phase separation, conductivity and maximal apparent viscosity. Additionally, electrolyte magnesium sulfate heptahydrate was more efficient in stabilizing these systems, compared to sodium chloride. The applied fractional factorial design method enabled determination of the optimal concentrations of the primary and secondary emulsifier, as well as the concentration of electrolytes, in order to obtain W/O/W emulsions with desired maximal apparent viscosities, low values of conductivity and without phase separation after centrifugation. 相似文献
143.
新工科的人才培养目标使混合式教学模式成为高校教学改革的重要趋势。云教材是与混合式教学模式相契合的教学资源。工程力学云教材的建设贯彻以成果为导向的教育理念,明确学习目标,集成富媒体数字出版、云服务和移动学习三大领域的前沿技术,为工程力学混合式教学提供配套的教学资源。实践应用表明,工程力学云教材提高了学生的学习兴趣和自主学习能力,助力新工科的建设。 相似文献
144.
紫外光引发制备高吸水树脂研究进展 总被引:3,自引:0,他引:3
首先介绍了紫外光(UV)引发及其常用的自由基光引发剂、光引发的特点、以及与γ射线辐射引发、微波辐射引发和电子束引发等三种引发方式相比较的优缺点等内容。然后就四种主要的光引发高吸水树脂:光引发乙烯基单体溶液聚合制备的高吸水树脂、光引发乙烯基单体接枝聚合制备的高吸水树脂、光引发制备复合高吸水树脂及光引发制备互穿网络(ISPN)高吸水树脂的研究进展进行了详细的阐述。最后指出了紫外光引发制备高吸水树脂需要加强的几个方向,即加强基础理论研究、开发新型高效光引发剂、开发新型复合高吸水树脂以及设计新的聚合工艺等。 相似文献
145.
根据卟啉类试剂的特性,从其在分析化学中的显色性、荧光性、超分子特性、电化学活性等方面,简要综述了近几年来卟啉类试剂在分析化学中的应用进展情况. 相似文献
146.
纳米荧光粒子YVO_4∶Eu的合成及其在指纹显现中的应用 总被引:1,自引:0,他引:1
以柠檬酸为络合剂,在水相中合成了悬浮稳定性较好的稀土YVO4∶Eu溶胶,采用XRD、TEM、荧光光谱等技术,研究了稀土荧光粒子的尺寸、形貌、晶胞参数及发光性能.结果表明合成的YVO4∶Eu荧光粒子为四方晶系,粒径约为10nm,分散性较好;在pH=9.0时合成的Y0.7VO4∶Eu0.3溶胶具有最大的荧光强度,其最大发射峰在619nm;经乙二胺四乙酸二钠表面修饰后的Y0.7VO4∶Eu0.3纳米荧光粒子能够清晰地显现出光滑客体上的指纹,颜色为红色. 相似文献
147.
148.
Reinout Heijungs Gjalt Huppes Jeroen B. Guinée 《Polymer Degradation and Stability》2010,95(3):422-1719
There are many approaches to study the environmental and sustainability aspects of production and consumption. Some of these reside at the level of concepts, e.g., industrial ecology, design for environment, and cleaner production. Other approaches are based on the use of quantitative models, e.g., life cycle assessment, material flow accounting and strategic environmental assessment. This paper focuses on the development of a framework that is able to incorporate different models for environmental analysis, with the option of a broader scope that also includes economic and social aspects, thus covering the three pillars of sustainability. This framework builds on the ISO-framework for life cycle assessment, but takes a broader view, and allows us to move from micro questions on specific products, via meso questions on life styles up to macro questions in which the entire societal structure is part of the analysis. 相似文献
149.
为探究金属有机骨架材料在指印显现领域的应用,本研究采用预混合迅速滴显的方法,使金属有机骨架材料Tb-BTC直接络合在指印纹线上.使用该材料对渗透性客体中A4纸、黑色卡纸、牛皮纸;非渗透性客体中透明玻璃片、瓷砖上的皮脂指印进行显现,探究了不同配比、不同滴加顺序、不同显现时间的预混合溶液对不同类型、不同遗留时间、不同遗留物... 相似文献
150.
简要介绍几年来我给北京大学物理学院三年级本科生讲授"量子力学A"课程的一些经验和体会.为了使学生们能够较为容易地理解量子力学的基本概念和原则,我尝试着从科学史的角度进行讲述,取得了较好的效果.同时,恰当地打一些比喻,对于学生们深刻领会某些相对来说抽象的概念也有很大帮助. 相似文献