酰胺醚SME15在氧化聚乙烯蜡乳液制备中的应用

采用相转变法和复合乳化体系对氧化聚乙烯蜡进行乳化,制备了稳定的氧化聚乙烯蜡乳液.结果表明:乳化剂的种类、用量、乳化温度以及剪切搅拌速度等因素对乳液性能有很大的影响.实验优化的乳化条件是:SME15用量为氧化聚乙烯蜡质量的10%,复合的乳化剂体系为m(SME)∶m(1631)=1∶3,总用量为氧化聚乙烯蜡质量的10%;或复合乳化体系为m(SME)∶m(K-12)=1∶3,总用量为氧化聚乙烯蜡质量的10%,乳化温度为90～95℃,在500～800r/min的转速下连续剪切分散40～60min.     

酰胺醚SME15在氧化聚乙烯蜡乳液制备中的应用

采用相转变法和复合乳化体系对氧化聚乙烯蜡进行乳化,制备了稳定的氧化聚乙烯蜡乳液。结果表明：乳化剂的种类、用量、乳化温度以及剪切搅拌速度等因素对乳液性能有很大的影响。实验优化的乳化条件是：SME15用量为氧化聚乙烯蜡质量的10%,复合的乳化剂体系为m（SME）∶m（1631）=1∶3,总用量为氧化聚乙烯蜡质量的10%;或复合乳化体系为m（SME）∶m（K-12）=1∶3,总用量为氧化聚乙烯蜡质量的10%,乳化温度为90-95℃,在500-800 r/min的转速下连续剪切分散40-60 min。     

氧化聚乙烯蜡乳液的制备及在皮革涂饰中的应用

采用相转变法对氧化聚乙烯蜡进行乳化制备氧化聚乙烯蜡乳液用于皮革涂饰。考查了乳化剂种类、用量、乳化温度及机械搅拌速度等主要因素对乳化效果的影响。结果表明:使用的乳化剂体系为OS-15与K-12或OS-15与1631,质量比分别为m(OS-15)∶m(K-12)=1∶3或m(OS-15)∶m(1631)=1∶1,其总用量分别为氧化聚乙烯蜡质量的10%和20%,乳化温度为90~95℃,机械搅拌速度为500~1000 r/min,可制备出均一稳定的氧化聚乙烯蜡乳液。皮革涂饰表明:使用氧化聚乙烯蜡乳液的涂层蜡感及润感较强,可增强皮革的真皮感效应,适用于软革的涂饰。     

聚乙烯蜡超细微乳液的制备及其性能研究

以聚乙烯蜡6 100为原料,采用直接高温高压法制备聚乙烯蜡微乳液;系统研究了乳化剂HLB值、乳化剂用量、乳化时间、乳化温度、pH、搅拌速度等因素对聚乙烯蜡乳液性能的影响,并分别采用场发射透射电子显微镜(FE-TEM)和激光动态光散射仪(DLS)等研究了乳液微粒形态、粒径及其分布.结果表明,适宜的乳化工艺条件:复合乳化剂的HLB为14.8,复合乳化剂用量为6.4%,乳化时间为40 min,乳化温度为130℃,搅拌速度为60 r/min,pH=8.在该条件下可制得固含量高达40%、平均粒径为50 nm、具有良好稳定性和分散性的聚乙烯蜡超细微乳液,该乳液可以赋予织物柔软丰满的手感,减少织物表面摩擦阻力,显著改善织物的可缝纫性等.     

氧化聚乙烯蜡微乳液的制备

氧化聚乙烯蜡在纺织行业有广阔的应用前景．考察了乳化剂的种类、用量、乳化时间、乳化温度、搅拌速度、助乳化剂等因素对乳液性能的影响．确定了采用高温高压直接乳化氧化聚乙烯蜡为微乳液的配方组成和乳化工艺条件。     

氧化改性聚乙烯蜡微乳液的制备及应用

以高密度氧化改性聚乙烯蜡Hi-Wax 4051 E为原料,采用直接高温高压密闭乳化法制备氧化改性聚乙烯蜡微乳液。探讨了乳化剂配比和总用量、乳化时间及乳化温度等因素对乳液性能的影响。优化的乳化工艺为:乳化剂总用量30%(相对氧化聚乙烯蜡质量,其中异构脂肪醇聚氧乙烯醚A与脂肪醇聚氧乙烯醚B的质量比为1∶1),快速升温到130℃,以一定的速度恒温搅拌乳化30min。制备的微乳液与聚氨酯并用,可提高针织物的抗起毛起球性;单独使用,可提升针织物的顶破强力。     

非离子型皮革手感蜡乳液的制备及应用

采用相转变法对由石蜡和蜂蜡组成的混合蜡进行乳化,制备皮革涂饰用手感蜡乳液。考察了乳化剂种类、用量、乳化温度及搅拌速度等因素对乳液性能的影响。结果表明:使用乳化体系为Span60、Tween80与平平加O-20组成的复合乳化剂,总用量为20%,乳化温度为75℃,搅拌速度为500~700r/min,得到了稳定的非离子型手感蜡乳液。皮革涂饰结果表明:最优工艺下制得产品的综合性能与进口样品相近。     

复合型硅蜡乳液的乳化工艺研究

以58#全精炼石蜡和长链烷基聚醚/氨基硅(PCAD)为原料,采用转相法和复合乳化体系对蜡进行乳化,并对乳液性能进行检测。结果表明:将该长链烷基聚醚/氨基硅作为辅助添加剂加入蜡中,可提高石蜡的乳化性。乳化工艺优化条件为:m(AEO-3)∶m(1631)=1.5∶3.0、搅拌速度700r/min、乳化温度80℃、乳化时间35min和乳化剂用量w(m_(乳化剂)∶m_(硅蜡))=0.2时,可制备出一种均匀稳定的硅蜡乳液,该蜡乳液用作皮革顶层的手感改善剂,可赋予皮革油润的蜡感和光泽感。     

低速常压逆转乳化法制备阳离子分散松香胶

以低速常压逆转乳化法制备了阳离子分散松香胶,对乳化剂的选择和用量、乳化温度、转相温度、搅拌速度、加料速度和稳定剂等进行了研究,测定了松香胶的粒径和电荷,并探讨了阳离子分散松香胶对纸浆Zeta电位的影响.     

乳化蜡的制备及在造纸中的应用

本文介绍了乳化蜡的制备方法,讨论了乳化剂、乳化温度、乳化时间、搅拌速度和粒径大小对乳化蜡稳定性的影响;评述了乳化蜡作为造纸施胶剂的研究及应用;最后指出了国内乳化蜡的现状和未来发展方向。     

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