细纱胶圈纺纱机理与齿形胶圈的设想

为了解决胶圈与罗拉之间、胶圈与胶圈之间存在滑溜差异的问题,分析了胶圈的工作原理,以及滑溜差异导致成纱条干差、引起胶圈磨损的原因;提出用齿形胶圈代替传统胶圈的设想,使胶圈被罗拉摩擦传动改为啮合传动而从根本上消除滑溜差异而提高纱线质量;同时指出齿形胶圈对制造和安装精度要求较高的缺点。     

细纱胶圈结构对成纱质量的影响

为提高纺纱质量、延长胶圈的使用寿命,探讨了细纱胶圈的结构特点,分析了胶圈结构、类型及工作情况,揭示胶圈中部凹陷的原因,分析胶圈厚度、内径、表面形状、材料对成纱质量的影响。说明成纱质量与胶圈结构密切相关,因此合理选用胶圈结构、改进和创新胶圈结构是提高纱线质量、延长胶圈使用寿命的有效途径。     

H1000型高速纺胶圈的研制与应用

针对高速纺胶圈使用中出现的问题分析。提出胶圈耐磨性、胶圈的整圈强度、胶圈的抗静电性、胶圈运转的稳定性、胶图的伸长率等是制约胶圈使用寿命及成纱质量的主要因素。据此选定了H1000型胶圈的配方体系及工艺改进，研制出H1000型胺圈，提高了胶圈的使用寿命，达到进口胶圈的使用效果。     

内外花纹胶圈的应用效果

胶圈是粗纱机、细纱机牵伸装置中的主要部件之一,而且在牵伸过程中对成纱质量关系重大。多年来,对胶辊与成纱质量的关系探讨较多,但对胶圈与成纱质量关系的探讨相比偏少。滕州纺织器材厂试制的内外花纹胶圈,这是对胶圈性能与成纱质量方面提出的新课题,有利于促进对胶圈性能方面的研究和探讨。1　内花纹胶圈的滑溜率问题下胶圈的运转是靠下罗拉转动,下胶圈表面与上胶圈表面在一定压力下利用下胶圈的摩擦力带动上胶圈运动。因此,上下胶圈都是靠摩擦力传动而工作,而且摩擦传动必须有一定的摩擦因数,而摩擦因数的大小又影响到胶圈的运行速度和滑…     

NDA内花纹胶圈试验分析

胶圈是细纱牵伸机构的重要元件。棉纱质量与胶圈的纺纱性能有关,降低胶圈的滑溜率,提高回转均匀性,加强胶圈外表面对纤维的控制能力,有利于改善棉纱质量。因胶圈是借助中罗拉摩擦带动胶圈内层使胶圈回转,故内层表面性能既要提高中罗拉带动胶圈回转能力,又要降低胶圈运动与下销棒之间产生的摩擦阻力,才能够达到降低胶圈回     

紫外线光照胶圈的应用探讨

通过普通胶圈与紫外线光照胶圈纺纱对比试验 ,表明紫外线光照胶圈优于普通胶圈 ,可以明显提高成纱质量     

NDA-B022型不处理胶圈性能及纺纱试验

针对胶圈胶料的抗静电及抗粘附要求，从配方组成上添加相适应的组分，胶圈无需进行表面处理就能达到纺纱工艺要求。介绍了NDA-B022型不处理胶圈胶料配方的设计思路．对胶料性能及胶圈物理性能进行了测试分析。与处理胶圈、Armstrong胶圈的纺纱对比试验表明，NDA-B022型不处理胶圈纺纱质量较好，能达到进口胶圈技术水平。     

梯式复合型胶圈在化纤赛络纺中的运用

简述梯式复合型胶圈内表面结构特点,以及与普通平光胶圈和内花纹胶圈的优缺点。通过梯式复合型胶圈与普通平光胶圈运行稳定性对比试验,着重探讨了改变张力架张力和改变后牵伸倍数对胶圈运行稳定性试验及其对成纱质量的影响。在一定理论分析的基础上,摸索出梯式复合型胶圈在纺纯化纤赛络纺过程中的工艺参数,同时,在纺纱实践中与RS-6939S型新型上销配合使用,结果表明:梯式复合型胶圈充分发挥了平光胶圈与内花纹胶圈的优点,性能稳定,是一种新型胶圈。     

NDA-B022不处理胶圈性能及纺纱效果

阐述了胶圈抗静电、抗粘附的机理,在制定胶圈的配方组成上添加相适应的组分,达到了胶圈无需表面处理,满足纺纱工艺的要求,克服了现有胶圈在生产及使用过程中的不足。经纺纱实际使用并与进口胶圈和现有处理胶圈做了全面比较,说明达到了阿姆斯壮(Armstrong)公司胶圈的水平。     

HX-0201型表面不处理胶圈的研制和使用

针对胶圈表面处理造成纺纱性能发生变化的问题，研制开发了表面不处理胶圈。分析了胶圈缠绕纤维的原因，指出通过优选胶料和配合剂进行解决的方法；对比分析了不处理胶圈与处理胶圈胶料的性能、胶圈内外层摩擦因数和扯断强力。通过纺纱试验表明，不处理胶圈滑溜率相对于处理胶圈减小，纺纱质量提高。     

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.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

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.     

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.     

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.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.