磷酸酯抗静电剂的合成及其性能

十二、十六和十八烷基磷酸酯可作为抗静电剂组分。通过单因素和正交试验,考察了脂肪醇与五氧化二磷的配料比、酯化温度、酯化时间和水解温度对产物性能的影响。十八烷基磷酸酯的优化合成工艺为:n(十八醇)∶n(P2O5)=2.5∶1,酯化温度80~85℃,酯化时间6 h,水解温度75℃;十六烷基磷酸酯的优化合成工艺为:n(十六醇)∶n(P2O5)=2.5∶1,酯化温度为70℃,酯化时间4~5 h,水解温度75℃;十二烷基磷酸酯的优化合成工艺为:n(十二醇)∶n(P2O5)=2.3∶1,酯化温度80℃,酯化时间5 h,水解温度75℃。磷酸酯中单酯含量越高,抗静电性能越好。     

烷基(酚)聚氧乙烯醚磺基琥珀酸单酯二钠盐的合成、性能及脱墨应用

通过AEO-9和TX-10,与顺酐及亚硫酸钠反应合成了烷基(酚)聚氧乙烯醚磺基琥珀酸单酯二钠盐,得到其较佳合成条件为:酯化反应n(醚):n(酐)=1:1.05,反应温度为90℃,反应时间为3h;磺化反应温度为85℃,反应时间为2h。测定了所得产物的表面活性并进行脱墨应用,结果表明,与生产用脱墨剂相比,其脱墨后白度提高,残余油墨量下降。     

常压法合成乙内酰脲的研究

研究了常压环境下Bucherer-Berg’s法合成乙内酰脲。通过调整原料配比、反应温度、反应时间等技术参数,得到的最佳反应条件为:m(羟基乙腈)∶m(水)=8∶100,n(羟基乙腈)∶n(碳酸氢铵)=1∶4;合成过程中二氧化碳的通入流量在投料阶段为0.7 L/min、保温阶段为1.2 L/min;酸化过程中n(硫酸)∶n(羟基乙腈)=1∶2;投料阶段的投料温度为80℃、时间为2 h;反应阶段的反应温度和时间依次为85℃下保温反应2 h、90℃下保温反应2 h。乙内酰脲的最终产率可达93.52%,纯度为98.5%。实现了乙内酰脲的高产率和高纯度的制备,为下一步工业化放大奠定了基础。     

聚硅氧烷基琥珀酸酰胺磺酸钠的研制与应用

研究采用磺化和乳化一步完成的新方法合成聚硅氧烷基琥珀酸酰胺磺酸盐(SISS).得到最佳T艺条件为:在n(氨基硅油GY):n(顺酐)=1.0:0.7,于70℃下酰胺化反应40min.n(亚硫酸钠):n(顺酐)=1.10:1.00,表面活性剂TG用量为酰胺化产物质量的50%,于80℃下磺化反应4h.测定了所得产物的表面活性、应用性能和稳定性.表面张力,临界胶束浓度、乳化力和钙皂分散力分别为2.65×10-2N/m、8.32×10-2mol/L、82 s和20%,乳液透明稳定.测试其对纯棉白布整理效果,并与未经改性的氨基硅油GY比较,结果表明SISS整理织物性能优异.     

甘油醚季铵盐型纺织柔软剂的制备及应用

以脂肪醇(ROH)和环氧氯丙烷(EPIC)在相转移催化条件下,反应得到中间体长链烷氧基缩水甘油醚,确定其最佳反应条件为:n(NaOH)∶n(EPIC)∶n(ROH)=1.2∶2∶1,50℃反应4 h,以此为原料和三乙胺盐酸盐反应得到3-十四烷氧基-2-羟基丙基三乙基氯化铵.最佳反应条件为:n(烷氧基缩水甘油醚)∶n(三乙胺盐酸盐)=1∶1,水浴温度30℃,反应时间3.5 h,收率可达92%.产物结构通过红外光谱及元素分析结果得以证实.通过对其表面性能和各项柔软指标的测定,证明该产物具备良好的柔软性.     

两步法催化潲水油制备生物柴油的研究

采用两步法催化高酸值潲水油制备生物柴油,第一步先用硫酸铁催化潲水油中游离脂肪酸和甲醇酯化生成脂肪酸甲酯(生物柴油),然后再用氢氧化钾催化潲水油中的甘油三酯和甲醇进行酯交换。结果表明,硫酸铁对酯化反应具有很强的催化活性,而且可以回收利用。通过正交试验得到最佳酯化反应参数:硫酸铁用量2%,反应温度95℃,醇油摩尔比10∶1,反应时间4 h,该条件下游离脂肪酸酯化率达97.22%。酯交换条件为:KOH用量1%,反应温度65℃,反应时间1 h,醇油摩尔比6∶1。经过两步催化,产品中总的脂肪酸甲酯(生物柴油)含量达97.02%。该两步催化法具有不产生酸化废水,不需要耐强酸设备,反应时间短,转化率高,同时硫酸铁可以回收重复利用等优点。     

元宝枫油乙酯制备工艺研究

以元宝枫油为原料,用碱催化法进行乙酯化反应,通过单因素试验和正交试验确定的最优工艺条件为:反应物摩尔比(n(元宝枫油)∶n(无水乙醇))1∶6,反应时间4 h,反应温度75℃,催化剂用量1.0%。在该工艺条件下,乙酯得率为98.7%。     

两步法催化废白土油制备生物柴油的研究

以废白土油为原料,采用酯化和酯交换两步法制备生物柴油。选用硫酸铁作为酯化催化剂,选用氢氧化钠作为酯交换催化剂。利用正交实验优化两步法工艺条件,得到酯化反应中各因素最佳的水平组合为硫酸铁用量4%、醇油摩尔比14∶1、反应温度70℃、反应时间3 h,得到酯交换反应中各因素最佳的水平组合为醇油摩尔比6∶1、氢氧化钠用量1.4%、反应温度70℃、反应时间2.5 h。在最佳的酯化和酯交换工艺条件下,总转酯率达到96.4%,所得的生物柴油主要质量指标与0#柴油接近。     

对羟基苯甲酸苄酯合成新方法

介绍了一种在固体超强酸催化作用下,氧化钙作吸水剂,二甲苯作共沸剂,对羟基苯甲酸与苄醇回流脱水直接酯化的新方法。详细探讨了影响酯化反应的各种因素,得出了酯化反应的最佳条件:n(对羟基苯甲酸)∶n(苄醇)∶n(二甲苯)=1∶3∶5,m(对羟基苯甲酸)∶m(SO42-/TiO2-Al2O3)=100∶7,回流反应4h。在此条件下,酯化产率可达90.7%。结果表明,该方法反应时间短,酯化产率高,工艺简单,催化剂活性高。     

对甲苯磺酸催化制备脂肪酸丁酯工艺研究

以对甲苯磺酸(PTS)为催化剂,大豆油和正丁醇为原料进行酯交换反应制备脂肪酸丁酯。考察醇油摩尔比、催化剂用量、反应温度以及反应时间对大豆油酯交换率的影响。结果表明,最佳合成工艺条件为:n(醇)∶n(油)=7.3∶1,w(PTS)=5%(以大豆油和正丁醇的总质量计),反应温度130℃,反应时间4.5h,在此条件下,酯交换率可达到89.4%。     

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