Issues in nonlinear stochastic grey box identification

Grey box identification refers to the practice of identifying dynamical systems in model structures exploiting partial prior information. This contribution reviews a method for stochastic grey box identification and surveys experiences and lessons of applying it to a number of industrial processes. Issues to be addressed include advantages and costs of introducing stochastics into the model, the question of what contribution must be expected from the model designer as opposed to what can be formalized in computer algorithms, and an outlook on future plans to resolve present shortcomings.     

Viscoelasticity of oxidized starch/low methoxy pectin mixtures in the presence of glucose syrup

The structural properties of mixtures of pectin, oxidized starch and glucose syrup were investigated using small deformation dynamic oscillation. In the absence of added calcium, preparations of low methoxy pectin with glucose syrup formed viscous solutions, which remained crystal-free at subzero temperatures. Samples of oxidized starch and glucose syrup, on the other hand, exhibited solid-like behaviour because of the crystalline nature of the amylose-like helices. Mixtures of the two polysaccharides with the co-solute clearly showed phase inversion from liquid to solid-like behaviour with increasing amounts of starch in the formulation. The transformation was reflected in the textural properties of samples, which varied from thick solutions to firm gels. The viscoelasticity of the system was modified further by the introduction of high methoxy pectin. Preparations of high methoxy pectin and glucose syrup formed rubbery gels whose amorphous nature underwent a glass transition during cooling.     

Co-carbonization of hard coals and coal extracts 2. The co-carbonization of medium- and high-rank coals with extracts

Studies on the influence of anthracene coal extracts on the carbonization process of medium- and high-rank coals were undertaken. Extracts from flame coal (Int. Class. 900) and gas-coking coal (Int. Class. 632) were used as additives. The blends prepared from the examined coals and the extracts exhibited better coking properties than the parent coals. The addition of extract to the coals gave an increase in the microstrength of the resultant cokes. The effects of co-carbonization of coking coals with extracts were increases in the size of the optical texture as well as in the degree of structural ordering of cokes. In the co-carbonization of semicoking coal with addition of coal extracts, a reduction in the size of the anisotropic units and a decrease in the crystallite height of cokes were observed. No modification of the basic anisotropy of coke from anthracite by coal extract was observed. With increasing extract content in anthracite/extract blends there was an increase in the degree of structural ordering of co-carbonization products. Extract addition was unable to modify the behaviour of fusinite. Based on the results of investigation of the influence of coal extracts on the carbonization of different-rank coals, a division of coals according to the modification of the optical texture of coke is given.     

美欧清洗工艺之比较

清洗技术受到全球和地区相关行业上下游技术的影响,并随其不断发展.清洗技术因地而异,不同国家和地区之间的清洗工艺存在一定差别,而这些差别主要是由地方市场因素和法律因素决定的. 　　……     

Equilibrium distribution of water in the two-phase system supercritical carbon dioxide–textile

When natural fibres are dyed in supercritical carbon dioxide, the addition of a small amount of water increases coloration. For a process design it is important to know how much water has to be added to obtain a desired humidity of both textile and carbon dioxide. In this work a thermodynamic model is proposed to calculate the distribution of water over the textile phase and the supercritical phase as a function of pressure and temperature. The phase equilibrium is described with Raoult's law for non-ideal fluids. The absorbed water in the textile is a condensed phase and is modelled here as a non-ideal liquid, using the NRTL-equation. The non-ideality of the supercritical phase is described by a solubility enhancement factor, a new equation derived from statistical thermodynamics. Although the model is applied to cotton, viscose, silk and wool, it can be used for all water absorbing textiles.