用于造纸废水处理的季铵型有机絮凝剂的制备

以尿素、二甲胺、氨水和环氧氯丙烷为原料,制备了一种季铵型有机高分子聚合物(PEDU),通过红外谱图分析证实了其含有季铵基、羟基等基团.采用正交实验和单因素实验研究了尿素、二甲胺、氨水分别与环氧氯丙烷的摩尔比以及反应温度、反应时间等5个因素对聚合絮凝剂阳离子度和造纸废水CODCr去除率的影响.结果表明,PEDU的最佳制备条件为:n(尿素)∶n(二甲胺)∶n(氨水)∶n(环氧氯丙烷)=0.08∶1.28∶0.30∶1,反应温度为70℃,反应时间为5h,此时阳离子度为5.49 mmol/g.按以上条件制备出的PEDU作为絮凝剂在常温、pH值7.0、絮凝剂用量50 mg/L 的条件下,处理造纸废水,CODCr去除率为67.9％.     

阳离子改性剂的合成及应用

以环氧氯丙烷、二甲胺和二乙烯三胺为主要原料,合成了阳离子改性剂,探讨了反应物的比例和用量、反应温度和反应时间对产品性能的影响.最佳合成工艺为:n(环氧氯丙烷)∶n(二甲胺)∶n(二乙烯三胺)=1.0∶1.0∶0.10,滴加温度控制在20~30℃,然后缓慢升温至70℃保温反应5 h.棉织物经阳离子改性剂处理后,在无盐的情况下用活性染料染色,可以达到常规染色织物的色深值(K/S值),同时还能减少染料及纯碱的用量并缩短染色时间.     

阳离子无甲醛固色剂的合成及应用

以环氧氯丙烷、二甲胺和二乙烯三胺为原料制得了阳离子固色剂,研究了原料的摩尔比、反应温度、反应时间等对产品性能的影响。结果表明,n(环氧氯丙烷):n(二甲胺):n(二乙烯三胺)=1.3:1:0.15,加料温度控制在20～25℃,升温至70℃,反应5h制得的阳离子固色剂固色效果较好。其最佳固色条件为:固色剂用量为2%,pH值为7,固色温度为60℃。固色后摩擦和皂洗牢度可以提高0.5～1.5级。     

阳离子醚化剂CHPTMAC的合成研究

以三甲胺水溶液、盐酸、环氧氯丙烷为主要原料合成阳离子醚化剂3-氯-2-羟丙基-三甲基氯化铵(CHPTMAC),测试并分析了原料用量、温度、时间、p H值对反应产物的影响,确定了最佳反应条件,并对产物进行提纯。结果表明,阳离子醚化剂CHPTMAC最佳合成条件为:环氧氯丙烷与三甲胺盐酸盐的摩尔比为0.95,温度40~45℃,时间5 h,p H值7.0~8.0,反应产物的有效含量≥69.00%。     

阳离子醚化剂的制备及应用

主要研究了阳离子醚化剂3-氯-2-羟丙基三甲基氯化铵(CHPT)的合成工艺条件，探讨了反应温度、盐酸质量分数、溶液pH值、环氧氯丙烷与三甲胺盐酸盐摩尔比对阳离子醚化剂合成的影响，并采用真空恒沸汽提(载气提取)的方法对产物进行提纯。利用该阳离子醚化剂在温度60-70℃，反应4h时，再用乙醇溶液浸泡，过滤、洗涤、真空干燥，制得高取代度阳离子淀粉(取代应为0．5)。将其应用在造纸过程中，可取得较好的助留效果。     

环氧氯丙烷开环合成1-棕榈酸-3-氯丙醇酯的研究

以棕榈酸、环氧氯丙烷为原料,使用醋酸铬为催化剂开环合成得到1-棕榈酸-3-氯丙醇酯,该方法成本低廉、产率高、选择性好。所得产物使用红外光谱及液相色谱、电喷雾离子质谱等手段进行表征,并对合成反应条件进行了优化,最佳条件为反应温度80℃,反应时间30h,催化剂用量8 mmol/L,棕榈酸/环氧氯丙烷物质的量比1∶1.2,该条件下其产率可达92%。     

新型有机高分子絮凝剂的合成及在造纸废水处理中的应用

以环氧氯丙烷和二甲胺为原料,三乙烯四胺为交联剂,制备了一种阳离子型有机聚合物,并将其作为絮凝剂用于造纸废水处理.研究了三乙烯四胺添加量、反应温度、n(环氧氯丙烷):n(二甲胺)、聚合时间等因素对聚合物黏度和阳离子度的影响,并考察了该聚合物用于造纸废水处理时,体系pH值、絮凝剂用量对絮凝效果的影响.结果表明,在常温、pH值6.0～7.0、絮凝剂用量20 mg/L的条件下,废纸造纸废水的SS、CODCr的去除率分别达到95.9%和75.2%,与常规絮凝剂PAC及PFS相比,该絮凝剂具有添加量少、絮凝沉降速度快、有害物质残余量低、处理效果良好等特点.     

乙撑双硬脂酸酰胺的合成（I）

用红外光谱法研究了由硬脂酸与乙二胺合成乙撑双硬脂酸酰胺的反应条件。得出：乙二胺加入温度应控制在８０￣１００℃间，胺全部加入后保温２０分钟；铵盐脱水以应温度为１７０－１８０℃间；脱水反应时间以２－３小时为宜。作为造纸消泡剂用原料，硬脂酸与乙二胺投料比可控制在２．０５：１（摩尔比）使乙二胺转化率大于９８％，有利于原料的利用及环境保护。     

新型有机高分子絮凝剂的合成及在造纸废水处理中的应用

以环氧氯丙烷和二甲胺为原料,三乙烯四胺为交联剂,制备了一种阳离子型有机聚合物,并将其作为絮凝剂用于造纸废水处理.研究了三乙烯四胺添加量、反应温度、n(环氧氯丙烷):n(二甲胺)、聚合时间等因素对聚合物黏度和阳离子度的影响,并考察了该聚合物用于造纸废水处理时,体系pH值、絮凝剂用量对絮凝效果的影响.结果表明,在常温、pH值6.0 ～7.0、絮凝剂用量20 mg/L的条件下,废纸造纸废水的SS、CODCr的去除率分别达到95.9％和75.2％,与常规絮凝剂PAC及PFS相比,该絮凝剂具有添加量少、絮凝沉降速度快、有害物质残余量低、处理效果良好等特点.     

甲氧羰基丙烯酸-6-L-抗坏血酸酯的合成及抑菌活性的研究

L-抗坏血酸作为一种安全高效的抗氧化剂广泛用于食品工业,然而L-抗坏血酸有稳定性不佳、脂溶性较差等缺点。本文以L-抗坏血酸和马来酸酐为主要原料,采用直接酯化法对L-抗坏血酸进行分子修饰,合成了甲氧羰基丙烯酸-6-L-抗坏血酸酯,对其结构进行鉴定后,确认为目标产物。反应条件为：马来酸酐和甲醇摩尔比1∶1,60℃保温反应2.5h得马来酸单甲酯;L-抗坏血酸和马来酸单甲酯在摩尔比2.5∶1的条件下,25℃-26℃反应32h得产物。实验表明：本产物保留了L-抗坏血酸高效的抗氧化性能,进一步对其抗细菌、酵母和霉菌的效果进行研究,生长曲线的测定可以表明产物有较广的抗菌谱系,对细菌、酵母和霉菌均具有较强的抑制作用,显著降低它们的最终生长量,而且效果优于常用防腐剂山梨酸钾,是一种有潜力的食品添加剂。     

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