亚麻/羊毛混纺纱的过氧化尿素漂白工艺

利用漂白剂过氧化尿素对亚麻/羊毛混纺纱的漂白工艺进行了探讨.在确定过氧化尿素质量浓度、漂白温度、漂白时间、EDTA用量等因素影响混纺纱漂白效果的基础上,利用正交试验确定了过氧化尿素漂白亚麻/羊毛混纺纱的优化工艺,即过氧化尿素8 g/L,焦磷酸钠6 g/L,pH值8,反应温度80℃,时间80 min.性能测试结果表明,过氧化尿素漂白亚麻/羊毛混纺纱的工艺条件温和,对纤维损伤小,利于环保及后续加工,工艺可行.     

过氧化尿素对亚麻短纤维的漂白工艺

文章研究了过氧化尿素对亚麻短纤维的漂白工艺特点,分析了漂白液p H值、温度、过氧化尿素用量、漂白时间对白度及断裂强度的影响。结果表明:过氧化尿素漂白效果好,纤维白度高,不易泛黄,强度损伤小。整个漂白过程易控制,不产生有毒气体,对环境无污染,且不会在漂白设备中产生硅垢沉积物,设备清洗容易。最佳工艺参数:漂白液p H值8、温度80℃、过氧化尿素质量浓度8 g/L、漂白时间50 min。漂白后的亚麻短纤维手感柔软,综合性能好,满足在棉纺设备上纺纱的技术要求。     

棉织物的双氧水丝素蛋白活化漂白工艺

将废弃丝素溶解制备成蛋白助剂,应用于棉织物双氧水漂白工艺中。探讨了丝素蛋白及其与硅酸钠复配对双氧水漂白织物白度、毛效、分解率和强度的影响。结果表明,丝素蛋白可以有效地提高双氧水在较低温度和较低碱性条件下的漂白效果,实现双氧水低温低碱漂白。优化的漂白工艺为:硅酸钠2 g/L,丝素蛋白1 g/L,30%双氧水20 mL/L,NaOH 1 g/L,70℃漂白50 m in。     

兔毛蛋白助剂在棉织物双氧水漂白中的应用

本文主要通过比较白度和毛效发现,硅酸钠、焦磷酸钠和兔毛蛋白用量分别为8g/L,2～8g/L,2～4g/L时,棉织物的漂白效果最佳,其中兔毛蛋白作为双氧水稳定剂的稳定作用比焦磷酸钠及硅酸钠的稳定作用好;复配时比例为硅酸钠用量为2g/L,焦磷酸钠用量为4g/L,兔毛蛋白用量为2g/L时,三种稳定剂复配后织物白度及毛效比两种稳定剂复配效果好.     

大豆蛋白织物漂白工艺研究

探讨了一步法和两步法漂白工艺对大豆蛋白织物的漂白效果.在一步法漂白工艺中,探讨了氧化剂过氧乙酸及双氧水在大豆蛋白织物漂白工艺中的应用.通过对温度、氧化剂用量、时间等的分析,得出其对漂白效果的影响规律,并通过正交试验选出较佳漂白工艺.在两步法漂白工艺中,优选出适合大豆蛋白织物的较佳漂白方法:先用双氧水漂白(双氧水10 g/L,硅酸钠2 g/L,45 min,80℃),然后用过氧乙酸漂白(过氧乙酸8 g/L,pH值为6,60 min,70℃),在此工艺条件下,可以得到较好的漂白效果,白度为61.16.     

大豆蛋白／棉混纺针织物的漂白工艺

分别采用还原漂白、氧化漂白、酶处理、氧化-还原双漂、还原-氧化双漂和氧-氧双漂等工艺对大豆蛋白/棉混纺针织物进行漂白.采用单因素试验和正交试验,测试了白度、强力和毛效等指标,确定优化漂白工艺为:煮漂(双氧水30 g/L,尿素5 g/L,碳酸钠5 g/L,高效精练剂2 g/L,硅酸钠3 g/L,渗透剂JFC 2 g/L,100 ℃处理90 min)→水洗→烘干→环利粉还原复漂(环利粉20 g/L,碳酸钠5 g/L,渗透剂JFC 2 g/L,95～100℃处理120 min)→水洗→烘干.     

尿素在棉针织物前处理中的应用

通过正交实验对硅酸钠和尿素在棉针织物前处理中的作用进行了详细的对比分析,验证了尿素能够控制过氧化氢的分解,织物处理后的白度、毛效、强力均能达到生产的要求。尿素具有价格低、漂白时间短、污染轻的优势,可以替代硅酸钠用于棉针织物前处理采用尿素做稳定剂的最佳工艺为:双氧水4g/L,尿素12g/L,NaOH 2g/L,JFC 2.5 g/L,浓度100℃,时间90min,浴比1∶20。     

助剂对过氧化尿素漂白亚麻短纤维性能的影响

分析了过氧化尿素的漂白特点,探讨了亚麻短纤维漂白性能的影响因素.试验表明:渗透剂JFC用量2.0~2.5g/L、焦磷酸钠用量2.5~3.0 g/L、络合剂EDTA用量3.5 g/L时,亚麻短纤维白度高、强力损伤低.     

紫绒低温氧漂工艺

通过测试漂白后紫绒的白度和碱溶解度,探讨了漂白工艺各因素对漂白效果的影响.其最佳低温氧漂工艺条件为:30%双氧水用量60 g/L,尿素用量2.0 g/L,焦磷酸钠用量2.8 g/L,氧漂温度45 ℃,时间3 h,浴比1:50.漂白后紫绒白度可达57.42,碱溶解度可达27.14%.     

碱煮和氧漂对汉麻织物染色性能的影响

以提高汉麻织物染色深度为目的,采用正交设计方法对碱煮练和漂白工艺进行了分析,并对碱煮练助剂进行了优化.结果表明,碱煮练最佳工艺为:氢氧化钠10g/L,亚硫酸钠3g/L,硅酸钠2g/L,浴比1:20,温度80℃,时间90min.使用多聚磷酸钠作助剂,可以提高碱煮练汉麻织物的染色深度.漂白最佳工艺为:双氧水8g/L,温度85℃,时间90min, pH值10~11,浴比1:20.漂白次数对汉麻织物染色性能有一定影响,两次漂白效果最好.     

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.     

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     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press