由工业氯化钡制备高纯度碳酸钡的研究

本文以工业ＢａＣｌ２．２ＨＯ为原料,采用混合溶剂法除去了Ｃａ＾２＋,Ｓｒ＾２＋等主要杂质,获取了高纯度ＢａＣｌ２．２ＨＯ。将所得高纯度ＢａＣｌ２．２Ｈ２Ｏ与ＮＨ４ＨＣＯ３反应,并经６０℃二次蒸馏水行销条,１２０℃干燥,制备了纯度为９９．９１％高纯度ＢａＣＯ３,其中的Ｃａ＾２＋,Ｓｒ＾２＋含量低于２０ｐｐｍ。     

流动注射分光光度法同时测定制革鞣液及废液中Cr2O3和Al …

利用流动注射交替注入二苯碳酰二肼（ＤＰＣ）／铬天青（ＣＡＳ）,采用分光光度法,于５４５ｍｍ波长处,同时测定制革鞣注及废液中Ｃｒ２Ｏ３和Ａｌ２Ｏ３的含量。测定频率４８次／ｈ,测定Ｃｒ２Ｏ３：ＲＳＤ≤２．１９１％;测定Ａｌ２Ｏ３：ＲＳＤ≤１．７３１％,与传统方法相比,具有简便、快速,准确等优点。     

铬铝鞣剂生产技术

本文介绍一种适于铬盐生产厂利用下脚铝泥制造适用于各种革鞣制的铬铝鞣剂。铬铝鞣 于常规铬鞣剂的葡萄糖还原法。其要点在于根据铝泥中Ａｌ２Ｏ３与Ｃｒ２Ｏ３含量的比例,补加适量的红矾,以其达到Ａｌ２Ｏ３：Ｃｒ２Ｏ３为１：２。产品鞣制效果完全达到制革工艺要求。     

25℃Na^＋,K^＋∥Cl^—,SO^2—4—H3BO3—H2O体系相平衡研究

实验测定了２５℃Ｎａ＾＋,Ｋ＾＋∥Ｃｌ％－２,ＳＯ＾２－４－Ｈ３ＢＯ３－Ｈ２Ｏ五元体系的溶解度关对所绘相图进行了分析,讨论了硼酸的分离及其对硫酸钠转化制硫酸钾的影响。     

西藏扎布耶盐湖冬季卤水25℃等温蒸发研究

本文依据Ｎａ＾＋、Ｋ＾＋／／ＣＯ３＾２－、ＳＯ４＾２－、Ｃｌ＾－－Ｈ２Ｏ五元水盐体系介稳相图，对西藏扎布耶盐湖冬季卤水进行了２５℃等温蒸发试验，研究了该卤水蒸发过程中盐类富集行为和析出规律，为该盐湖卤水的综合利用提供可靠的依据。     

变型二浴法影响成革铬含量的因素

本文对变型二浴法鞣制，影响成革Ｃｒ２Ｏ３含量的主要因素进行了探讨，结果表明：ＮａＣｌ、Ｈ２ＳＯ４，一浴铬液的用量及铬液和红矾的加料顺序，皮的不同部们至成革铬含量影响较大。     

由工业氯化钡制备高纯度碳酸钡的研究

本文以工业ＢａＣｌ２·２Ｈ２Ｏ为原料,采用混合溶剂法除去了Ｃａ２＋、Ｓｒ２＋等主要杂质,获取了高纯度ＢａＣｌ２·２Ｈ２Ｏ。将所得高纯度ＢａＣｌ２·２Ｈ２Ｏ与ＮＨ４ＨＣＯ３反应,并经６０℃二次蒸馏水洗涤,１２０℃干燥,制备了纯度为９９．９１％高纯度ＢａＣＯ３,其中的Ｃａ２＋、Ｓｒ２＋含量低于２０ｐ     

亚法清净硫熏中和工艺条件的探讨

实验证实亚法糖汁精净中清汁ＳＯ２－３和Ｃａ＾２＋含量随熏强度和中和ＰＨ值升高而下降。采用中性偏码和高硫熏强度的工艺条件，能降低清汁中ＣａＳＯ３的含量，增加ＣａＳＯ３的沉淀量，显著减少青汁中ＳＯ＾－３和Ｃａ２＋的含量，有效提高清汁的品质。     

放大反应滴定法测定食品中的微量碘

依据Ｉ－的还原性的Ｉ２的氧化性原理，通过Ｂｒ２氧化样品中的微量Ｉ－为ＩＯ＾－３，而后煮沸除去Ｂｒ２，加过量ＫＩ并酸化，然后将反应生成的Ｉ２用ＣＨＣｌ３萃取，再用ｐＨ１１－１２碱液反萃取，再重复前述氧化反应等步骤，这时样品的微量碘已被放大了３６倍，最后用低浓度标准Ｎａ２Ｓ２Ｏ３溶液滴定，测出食品中微量碘的含量。     

硫酸镁转化法制取硫酸钾的最佳工艺条件的探讨

本文得用Ｋ＾＋，Ｍｇ＾２＋∥Ｃｌ＾－，ＳＯ＾２－４－Ｈ２Ｏ２５℃体系相图，对硫酸镁两段转化法制取硫酸钾的工艺过程进行了分析和计算，并对最佳工艺条件进行了探讨。     

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