涡流纺纱线性能分析

研究涡流纺成纱性能.采用相同熟条纺制了CJ 20 tex涡流纺纱线、传统环锭纺纱线、紧密纺纱线和喷气纺纱线,通过分析对比了这4种纱的成纱结构、毛羽、耐磨性及强伸性能,认为涡流纱成纱强力虽低于紧密纺纱线和传统环锭纱,但强力不匀较好,毛羽大幅度降低,耐磨性能很好,抗起毛起球性能好.     

不同纺纱方法纺制的棉涤混纺纱质量对比分析

探讨棉涤混纺赛络纱、赛络AB纱和传统环锭纱的质量。分别纺制了四种不同纱号的棉/涤60/40混纺赛络纱、赛络AB纱和传统环锭纱,测试了各纱强伸、毛羽和条干性能,并分析了每种纺纱方式的特点和适应性。结果表明:赛络纱、赛络AB纱在强伸性能、毛羽数量、条干质量方面均明显优于传统环锭纱,而赛络纱与赛络AB纱相比,强力、条干指标稍优,毛羽水平基本相当。认为:赛络纺纱方法是提高棉涤混纺纱质量水平的有效途径,不同纺纱方法具有不同的特点和适应性。实际生产中,应根据纺纱原料、所纺纱号质量要求以及纺纱条件选择适宜纺纱方法,纺制出满足用户质量要求的纱线,适应市场的需求。     

集聚纺纱方式对纱线性能的影响

为了探究集聚纺纱方式对纱线性能的影响,采用以传统环锭纺为基础的四罗拉网格圈紧密纺、紧密赛络纺、全聚纺及低扭矩纺四种集聚纺纱方式纺制了28.1、18.5、14.7 tex的纯棉纱。通过对纯棉纱线的断裂强度、断裂伸长率、毛羽和条干均匀度等性能进行测试分析,探究了四种集聚纺纱方式对纱线性能产生影响的原因。实验结果表明:由于不同集聚纺纱方式的成纱结构特点不同,影响了纱线的内在性能。紧密赛络纺的成纱强力最高,全聚纺的成纱有益毛羽最多,低扭矩纱在假捻器的作用下纱线品质得到了提高其纱线条干最好,紧密赛络纺的纱线总毛羽数最少。     

19.6tex52/48苎麻/精梳棉喷气涡流纱生产实践

运用喷气涡流纺技术纺制苎麻/精梳棉混纺纱,通过选定合理的苎麻预处理方案,正确配置前纺各工序及喷气涡流纺工序的工艺参数,并根据苎麻纤维的特点,在各工序运用合理的技术措施,成功纺制出19.6 tex 52/48苎麻/精梳棉喷气涡流纱,并对纱线性能进行了测试,与环锭纺纱线性能进行比较,得出其单纱断裂强力和纱线条干方面与环锭纺纱线性能相当,但毛羽性能明显好于环锭纱,可满足织造要求。     

喷气涡流纺与环锭纺纱线结构和性能对比

介绍了喷气涡流纺和环锭纺的成纱机理,通过试验对比分析了喷气涡流纺和环锭纺纱线的结构和性能差异。研究表明,喷气涡流纱的表观直径较相同特数的环锭纱小,断裂强度和条干均匀度略差于环锭纱,但喷气涡流纺具有纺纱速度快、纱线毛羽少等优点,未来具有良好的发展前景。     

牛角瓜纤维纯纺36.4tex纱的开发

为了开发牛角瓜纤维纯纺纱线,提高其成纱质量,介绍牛角瓜纤维的主要性能,从梳理、并条、粗纱和细纱等工序分析牛角瓜纤维纯纺环锭纱的生产工艺参数和原则,针对牛角瓜纤维纯纺纱断裂强度偏低、条干均匀度差、毛羽较多等问题,采用赛络纺、集聚纺和集聚赛络纺等纺纱方法对其纺纱工艺进行优化,对比分析3种方法所纺36.4tex纱性能。结果表明:采用转杯并合凝聚工艺,可改善牛角瓜纤维的可纺性;降低车速、调整车间温湿度,明显减少环锭纺并条工序绕胶辊和罗拉;赛络纺显著改善纱线条干,集聚纺有效减少纱线毛羽,集聚赛络纺对纱线毛羽和条干均有明显改善,且3种方法都可使纱线断裂强度略有提高;当细纱工序采用集聚赛络纺时,纱线性能可以满足织造要求。     

聚乳酸纤维赛络纺工艺研究

通过改变粗纱间距、粗纱捻系数及细纱后区牵伸倍数研究了聚乳酸纤维赛络纺工艺,分析了不同纺纱工艺对纱线断裂强力、条干不匀率及毛羽指数变化的影响,得到了聚乳酸纤维赛络纺的较优纺纱工艺.在同一台细纱机上,采用相同的粗纱捻系数及牵伸工艺,同时纺制了23.9 tex聚乳酸纤维环锭纱和赛络纱.两种纱线的断裂强力均呈正态分布,两者波动性无明显差异,且前者断裂强力显著高于后者;聚乳酸赛络纱的毛羽有明显改善;两种纱线的条干差异不大,环锭纱略好于赛络纱.     

纺纱工艺对不锈钢纤维/粘胶纤维混纺纱成纱性能的影响

为探讨纺纱工艺对不锈钢纤维/粘胶纤维混纺纱成纱质量的影响,分析纱线中最佳不锈钢纤维含量,采用环锭纺纱工艺与赛络纺纱工艺条件纺制不同不锈钢纤维含量的不锈钢纤维/粘胶纤维纱线,并利用条干均匀度、纱线毛羽指数与纱线力学指标表征成纱质量。测试表明:2种纺纱工艺制纱的条干均匀度、纱线毛羽指数与纱线力学性能随着混纺纱线中不锈钢纤维含量升高而下降,且在同等不锈钢纤维含量条件下,采用赛络纺纱工艺条件纺制混纺纱的条干均匀度、纱线毛羽指数与纱线力学性能优于环锭纺纱工艺。认为:采用赛络纺纱工艺条件纺制不锈钢纤维含量12%的不锈钢纤维/粘胶纤维混纺纱线能够保证纱线的质量与可织性。     

不同纺纱方式对竹浆纤维混纺纱线性能的影响

为研究不同纺纱方式对竹浆纤维混纺纱线性能的影响,采用竹浆纤维、棉纤维、涤纶纤维与粘胶纤维进行混纺,混纺比例为15/40/30/15。通过对竹浆纤维混纺纱线的条干均匀度、毛羽、断裂强度、断裂伸长率等性能进行测试分析,探究了纺纱方式对成纱性能产生影响的原因。结果表明:由于转杯纺、赛络纺、环锭纺、赛络紧密纺、普通紧密纺纺纱方式不同,其不同的成纱结构特点影响了纱线的内在性能。环锭纱适宜生产强力要求较高的产品,紧密纱综合性能较好,赛络纱具有良好的外观特征,转杯纱的条干CV值优于环锭纱,赛络紧密纺的成纱毛羽最低。     

全聚赛络纺集聚负压对成纱性能的影响

全聚纺是一种新型窄槽式负压罗拉型紧密纺系统。全聚赛络纺是将全聚纺与赛络纺纱技术相结合的一种纺纱方法,可显著提高成纱质量。叙述了全聚赛络纺纱的技术原理;在4种不同集聚负压下分别纺制29.2、14.6、9.7 tex全聚赛络纱,分析负压对纱线条干、强力、毛羽性能的影响。结果表明:对于成纱条干,纺制粗特纱时,负压较大有利于改善纱线的条干,而在纺制中、细特纱时负压应适当减小;对于成纱强力,选择较大的负压有助于提高粗特纱的强力,纺制中、细特纱应适当降低负压;当负压增大时,纱线的3 mm以上有害毛羽逐渐减少。     

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.     

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.     

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.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the