橡毯预缩机预缩率软测量模型

针对染整后整理预缩工序,由于橡毯预缩机预缩效果的影响因素多而复杂,难以实现预缩率的在线预测和预缩工艺的精确定量设计问题,采用机理建模的方法,分析橡毯预缩机橡胶毯的变形机理,建立了预缩率与对其影响最大的因素挤压力之间的软测量模型。实例结果表明：根据所建立软测量模型计算出的预缩率与实测值的相对误差均在8%以内,平均绝对百分比误差为5.1041%,该软测量模型是可行有效的,对预缩率在线预测和预缩工艺的精确定量设计具有指导意义。     

国外简讯

机械预缩机的新一代弹性橡胶毯 据法国Rollin SA公司报道,其提供用于机械预缩机的TOP Shrink弹性橡胶毯具有使用寿命长,性能稳定,耐弯耐压,外观不易变形等优点。 织物机械预缩的均匀性和规一性,很大程度上取决于织物本身的性质和采用的预缩方法、预缩机和弹性橡胶毯。 织物在湿热状态下,通过弹性橡胶毯粘附性能的连接作用,使经纬密度增加,实现机械预缩。然后当织物离开预缩机时,即刻烘干,使缩率永久固定。机械预缩还能改善织物的外观,如光泽和手感。 预缩过程可以分成二个主要步骤进行,预缩阶段,通过橡胶毯挤压,使织物预缩;热固阶段,通过橡胶毯和加热转鼓作用使织物缩率固定。 预缩的产生是由于弹性橡胶毯的挤压作用,降低了织物的运行速度,另一方面,使织物的纱线均匀滑移。     

影响织物预缩率的重要因素分析

介绍了橡毯预缩机的预缩原理,着重分析影响织物预缩率的因素。     

YG801型伸缩比率计在防缩整理机上的应用

织物“缩水”的稳定性,是评定织物质量的重要指标之一。采用机械预缩整理法,使织物预缩后达到降低缩水率的要求。织物的预缩效果是以织物预缩前后的缩率来衡量。织物预缩率的多少和三辊橡毯预缩装置的橡毯厚度和张力、进布加压辊和加热承压辊之间的间隙、加热承压辊的直径和温度、织物含湿率及车速等因素都有密切关系。由于影响织物预缩率的参数颇多,要了解经调整某参数后,预缩率的变化情况必须进行人工测定。     

针织物汽蒸式预缩机的设计原理

服装材料在加工制作过程中，经过织造、精炼、染色、整理等各种理化处理，由于在各道工序中所受的强烈的机械张力，导致织物内部存在着不同的应力和其它病疵，这种情况若在制作服装前不加以消除，将会不同程度地影响服装产品的形态稳定性、穿着性能等。预缩整理正是消除和纠正这种影响的一种必要的工序，预缩机是具有对织物预缩整理功能的机械。预缩机的种类很多，通常有机械式的预缩机（如橡胶毯式、呢毯式、挤缩式等）；汽蒸式预缩机；超声波水汽雾化预缩机以及冷冻蒸发预缩机等。前一种预缩机（机械式）使用比较多，后两种预缩机由于结构…     

电子数字测缩仪

上海色织七厂在革新成功多滚筒预缩机之后,技革小组和电工组又试制成功一台电子数字测缩仪,从而改变了预缩机测量缩率靠目测手量的落后状态,提高了劳动生产率。 这种电子测缩仪的工作原理是:棉布经过预缩机预缩后,长度缩短,纬密增加,进布导     

织物预缩机介绍

一、Sanforize预缩机作为防缩整理用的预缩机,目前已有多种形式。Sanforize 预缩机是1934年由美国Sanford CIuett 所发明的,并以此工艺为开端,Sanforize 预缩机的压缩部分,如图一所示。     

基本型预缩整理机简介

去年11月份由纺织部召开了预缩机改造座谈会,根据上海印染机械厂设计制造的LMH751-160型预缩整理机安装试用后的情况,结合国内外有关预缩整理机的使用情况（附表）,确定对各单位现有的简易预缩机进行改造的方案,初步定名为基本型预缩整理机。兹将确定的方案介绍如下:     

印染厂节能减排实用工艺装备技术(二十)——织物缩水率的控制

分析了织物染整加工过程中潜在的缩水率原因,提出了防止潜在缩水率的措施,包括树脂整理、机械预缩、丝光和紧式加工等,阐述了预缩机理,重点介绍了影响预缩效果的要素、预缩工艺参数的在线控制等,以获得精确、稳定、重现优良的预缩率,确保成品缩水率达标.     

丝绸面料需预缩处理的缩率临界值判断

分析服装企业现实生产中面料缩率对服装质量产生的影响,指出面料投入服装生产前判断其是否需预缩处理的必要性,并找出需预缩处理的缩率临界点判断方法,求得预测实际缩率的计算公式和面料需预缩的临界缩率判别公式.     

Encapsulation of food ingredients

Microencapsulation is a relatively new technology that is used for protection, stabilization, and slow release of food ingredients. The encapsulating or wall materials used generally consist of starch, starch derivatives, proteins, gums, lipids, or any combination of them. Methods of encapsulation of food ingredients include spraydrying, freeze‐drying, fluidized bed‐coating, extrusion, cocrystallization, molecular inclusion, and coacervation. This paper reviews techniques for preparation of microencapsulated food ingredients and choices of coating material. Characterization of microcapsules, mechanisms of controlled release, and efficiency of protection/ stabilization of encapsulated food ingredients are also presented.     

Depth of concussion in cattle shot by penetrating captive bolt

The prevalence of shallow depth of concussion following captive bolt shooting was assessed in 1608 cattle at an abattoir. Depth of concussion was determined in each animal from physical collapse, presence or absence of corneal reflex, normal rhythmic breathing, eyeball rotation, and whether the animal was re-shot. The presence of nystagmus and the absence of tongue protrusion were also monitored as potential indicators of a shallow depth of concussion, and simultaneous noise measurements assessed whether loudness of gun discharge was linked to concussion depth. The prevalence of a shallow depth of concussion was 8% for all cattle and 15% for young bulls. Nystagmus was associated with other indicators of a shallow depth of concussion. Absence of tongue protrusion was not associated with depth of concussion, but could serve as a useful indicator of jaw relaxation and insensibility following exsanguination. Soft-sounding shots (111 dB) when using 4.5 gr cartridges were associated with shallow depth of concussion.     

39—THE FLOW OF LIQUID FROM A JET THROUGH A COMPRESSIBLE POROUS LAYER. PART III: THE CHARACTERISTICS OF LIQUID FLOW THROUGH A COMPRESSIBLE LAYER OF LOOSE WOOL

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.     

Headspace solid‐phase microextraction analysis of artificial flavors

Using a non‐equilibrated solid‐phase microextraction/gas chromatography/mass spectrometry technique, differentiation between a wide variety of types and examples of artificial flavors has been demonstrated. Addition of an internal standard to the samples, as received, allowed for the calculation of yields on a µg g^?1 basis for the majority of headspace volatiles. The relative standard deviation values expressed as percentages were between 3 and 5%. The precise nature of the approach coupled with the compound identification capacity of the mass spectrometer afforded the capability to easily differentiate between multiple sources of artificial flavors. With a total analysis time of approximately 30 min and the absence of solvent, this approach has the capability of detecting and quantifying the presence of the low‐molecular‐weight solvents often used in the preparation of artificial flavors. Such a capability represents a distinct advantage over more conventional methods of solvent dilution. Results from conventional gas chromatography/mass selective detector analyses are contrasted and compared with the results obtained from the headspace SPME approach. Copyright © 2005 Society of Chemical Industry     

21—THE ACETYLATION OF COTTON

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.     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Biodegradation of genetically modified seeds and plant tissues during composting

BACKGROUND: The increasing global market of genetically modified (GM) crops amplifies the potential for unintentional contamination of food and feed with GM plants. Methods proposed for disposal of crop residues should be assessed to prevent unintended distribution of GM materials. Composting of organic material is inexpensive and location‐independent. The objective of this study was to determine the effectiveness of composting for disposal of GM plants in terms of reducing seed viability and promoting the degradation of endogenous as well as transgenic DNA. RESULTS: Duplicate samples of corn kernels, alfalfa leaves, and GM canola seeds, meal and pellets were sealed in porous nylon bags and implanted in duplicate 85 000 kg (initial weight) feedlot manure compost piles. Samples were collected at intervals over 230 days of composing. Canola seeds and corn kernels were not viable after 14 days of composting with temperatures in the piles exceeding 50 °C. In all samples, PCR analyses revealed that plant endogenous and transgenic fragments were substantially degraded after 230 days of composting. Southern blotting of genomic DNA isolated from canola seeds identified differences in the persistence of endogenous, transgenic, and bacterial DNA. CONCLUSION: Composting GM and non‐GM plant materials with manure rendered seeds non‐viable, and resulted in substantial, although not complete, degradation of endogenous and transgenic plant DNA. This study demonstrates that composting could be effective for disposing of GM crops in the event of their inadvertent entry into the food or feed chain. Copyright © 2010 Crown in the right of Canada. Published by John Wiley & Sons, Ltd     

The inhibitory effect of some amphoteric surfactants on the irritation potential of alkylsulphates

The physico-chemical and biological properties of an amphoteric/anionic system and its behaviour against a proteinic support have been thoroughly investigated. A considerable inhibition of adsorption of SLS (sodium lauryl sulphate) on human callus caused by the presence of definite amounts of AABet (alkyl-amido-betaines) in the treatment bath is observed. These physico-chemical results are in agreement with those obtained by some in vivo biological tests. A mechanism of the process via the formation of mixed micelles is postulated emphasizing the stability of such systems as a function of pH, the influence of the chain length of the amphoteric surfactant and the molar relative ratio SLS/AABet. Consequently, our work offers the possibility of a wide applicability of the synergic mixtures of both types of surfactants to inhibit considerably skin irritation of cosmetic finished products.