超高分子量聚乙烯纤维/氨纶包芯纱的生产技术

探讨超高分子量聚乙烯纤维/氨纶包芯纱的生产工艺。介绍了纺制17 tex超高分子量聚乙烯纤维/氨纶包芯纱纺纱工艺流程,对各道工艺进行优化,做好温湿度控制工作,并采取相应的技术措施最终顺利纺制出超高分子量聚乙烯纤维氨纶包芯纱,纱线质量达到较好水平。     

聚乳酸纤维包芯纱的开发

探讨聚乳酸纤维包芯纱的生产工艺.阐述了在环锭细纱机上纺制聚乳酸纤维包芯纱的方法及各生产工序的工艺要点,并通过正交试验确定了纱线捻度和细纱后区牵伸倍数的最优工艺配置,最终顺利纺制出了21.4 tex(55.6 dtex)聚乳酸纤维包芯纱,质量达到了较好水平.     

芦荟纤维绢丝棉氨纶包芯纱的纺制

探讨芦荟纤维绢丝棉氨纶包芯纱的纺纱工艺。阐述了芦荟纤维、绢丝的性能特点,通过原料选配及预处理以改善原料的可纺性,各工序合理配置工艺参数,采取必要的技术措施,最终成功地纺制出40tex(44.4 dtex)芦荟纤维绢丝棉氨纶包芯纱,并通过正交试验优选氨纶丝预牵伸倍数和纺纱捻度两项关键工艺参数,得出较优的纺纱工艺配置为氨纶丝预牵伸4.0倍,捻度60捻/10 cm,使纺制出的芦荟纤维绢丝棉氨纶包芯纱质量满足了使用要求。     

影响氨纶包芯纱性能主要因素的研究

对纺制氨纶包芯纱的主要工艺参数 ,如预牵伸倍数、外包纤维比例、包芯纱的捻度以及钢丝圈型号进行了工艺试验 ,并对不同工艺参数对氨纶包芯纱主要性能的影响进行了分析和探讨     

影响氨纶包芯纱性能主要因素的研究

对纺制氨纶包芯纱的主要工艺参数,如预牵伸倍数、外包纤维比例、包芯纱的捻度以及钢丝圈型号进行了工艺试验,并对不同工艺参数对氨纶包芯纱主要性能的影响进行了分析和探讨。     

弹力包芯纱弹性与包覆效果的研究

弹力包芯纱的特征就是具有弹性,对织物染整效果影响较大的就是其外包纤维的包覆均匀性。分别对氨纶丝、氨纶包芯纱和弹力布的拉伸特性作了试验分析,指出了三者之间的联系;还从不环锭纺、喷气纺纺纱原理方面分析了弹力包芯纱包覆均匀性的问题,指出了改善弹力包芯纱性能的要求,提出了评定弹力包芯纱弹性和包覆效果的方法。     

彩色涤纶仿蚕丝弹力纱的开发

为顺利生产彩色涤纶仿蚕丝氨纶弹力包芯纱,使成纱光泽均匀,针对异彤截面涤纶纤维原料的性能特点,进行了纺纱试验.生产中红、黄、蓝3种有色涤纶纤维与白色涤纶纤维要进行抗静电预处理,分别成条经预并后再进行三道混并,以加强混和,各纺纱工序针对涤纶纤维静电严重问题合理配置速度等相关工艺.结果表明:通过优化工艺及采取相应技术措施,纺制的14.8 tex(44 dtex)彩色涤纶仿蚕丝氨纶弹力包芯纱质量达到技术要求,成纱光泽柔和,色彩丰富.     

纺纱方法对棉海藻纤维氨纶包芯纱性能的影响

探讨纺纱方法对棉海藻纤维氨纶包芯纱性能的影响.采用赛络纺和传统环锭纺两种纺纱方法、5种外包纤维混纺比纺制棉海藻纤维氨纶包芯纱,并进行了性能测试分析.结果表明:纺纱方法对棉海藻纤维氨纶包芯纱质量有较大影响,采用赛络纺可明显地提高成纱强伸性能、改善条干、减少有害毛羽.外包纤维中,棉与海藻纤维混纺比以65/35时,所获得的纺纱改善效果较好.认为采用赛络包芯纺工艺以及适宜的外包纤维混纺比,可改进在棉海藻纤维氨纶包芯纱成纱质量.     

赛络纺棉氨纶包芯纱的生产及应用

为了提高弹力牛仔布质量,试纺了赛络纺棉氨纶包芯纱,并与传统环锭纺棉氨纶包芯纱的成纱质量进行了对比.通过合理配棉,优化纺纱工艺,赛络纺棉氨纶包芯纱顺利纺制,其条干、强度及毛羽等主要质量指标优于传统环锭纺棉氨纶包芯纱,且包覆效果好,织制的弹力牛仔布布面光洁,纬向缩率减小,纬向色档疵点消除.     

牛奶蛋白纤维混纺弹力纱的开发

介绍了牛奶蛋白纤维的特性,牛奶蛋白纤维既有天然蚕丝的优良特性,又有合成纤维的性能特征,可纺性能良好,是一种全新的纺织材料.牛奶蛋白细号涤纶棉混纺弹力包芯纱的生产采用牛奶蛋白纤维与细号涤纶棉包混和制条,再与棉纤维精梳条混和纺制氨纶包芯纱的工艺路线.     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

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.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

Influence des ions sur le pouvoir hydratant de l'ure e: e tude sur peau de porc ex vivo

This study deals with the influence of ions (NaCl and MgSO4) in a W/O emulsion containing 10% urea. Moisturization kinetics are assessed by corneometry on pig skin ex vivo. The formula's influence on urea penetration is measured by infrared spectrometry with an ATR device and the stripping method. Corneometry and spectroscopy were chosen to record simultaneously the hydratation levels and urea localization into superficial cell layers. Urea crystallization after evaporation of emulsions and aqueous solutions is described. Results show that urea does not hydrate nor penetrate when applied to the skin through an aqueous gel. In a W/O emulsion, sodium chloride increases the ability of urea to moisturize without improving penetration. In vitro urea crystallization is disturbed by sodium chloride or magnesium sulphate for solutions and emulsions. This stabilization by ions is correlated with good moisturization values. The stabilization of urea in the solute state provided by ions increases its water epidermal binding capacity without enhancing penetration.