制备方法对Ag－SnO_2材料结构与气敏性能的影响

采用化学浸渍法和光照分解法合成了银掺杂的ＳｎＯ２气敏材料，用Ｘ射线衍射法分析了材料的物相组成，用Ｘ光电子能谱研究了材料的价键结构，用静态配气法测试了材料的气敏性能．结果表明：浸渍法Ａｇ－ＳｎＯ２的气敏性能优于光照分解样品，光照波长为４１５ｎｍ时，样品的气敏性能优于其它波长照射的样品。经ＸＲＤ谱图分析，浸渍法Ａｇ－ＳｎＯ２样品没有Ａｇ物相分离，而光照法样品出现Ａｇ２Ｏ２和ＡｇＣｌ物相。浸渍法样品的ＸＰＳ谱图表明，Ａｇ在ＳｎＯ２的表面以Ａｇ和Ａｇ２Ｏ组成．     

掺杂镍酸镧材料的气敏特性研究

研究了ＴｉＯ＿２掺杂ＬａＮｉＯ＿３的气敏特性，实验表明，在中等掺杂时，材料的电导适中，气敏性能最好；ＸＲＤ证实，掺杂后ＬａＮｉＯ＿３仍属于ＡＢＯ＿３钙钛矿结构，且有新相生成。还对掺杂ＳｎＯ＿２，Ｓｂ＿２Ｏ＿３及Ｖ＿２Ｏ＿５进行了研究，指出ＳｎＯ＿２中等掺杂及Ｓｂ＿２Ｏ＿３，Ｖ＿２Ｏ＿５低掺杂时，同样能使ＬａＮｉＯ＿３的气敏性质有所改善。     

用PECVD制备的SnO_2薄膜气敏特性研究

ＳｎＯ２薄膜制备及其应用日益受到人们的重视。本文阐述了用低温等离子体化学气相沉积法制备ＳｎＯ２薄膜的工艺，并研究了所制得的纯净及掺杂Ａｇ，Ｐｄ的ＳｎＯ２薄膜的气敏特性。此法制得的元件对还原性气体，尤其是低浓度Ｈ２Ｓ，Ｃ２Ｈ５ＯＨ具有很高的灵敏度及快速的响应．     

SnO_2－SiO_2双层薄膜氢敏元件的特性研究

采用溶液－凝胶浸渍涂布工艺在Ａｌ＿２Ｏ＿３陶瓷管上制备了掺杂ＳｎＯ＿２气敏薄膜；利用高温热解法在ＳｎＯ＿２薄膜表面覆盖ＳｉＯ＿２气体分离膜后制得双层薄膜气敏元件。分别测试并比较单层和双层薄膜元件的气敏特性，结果表明：单层薄膜元件对可燃性气体无选择性、响应和恢复时间短；而双层薄膜元件对氢气表现出极高的灵敏度和优越的选择性，其响应和恢复时间都比单层薄膜元件有所延长，结合实验结果，从理论上阐述了双层薄膜元件对氢气的敏感机理。     

高白度麦草浆OP两段漂白的研究

本文研究了ＳＳＡＱ麦草浆ＯＰ两段漂白的工艺。结果指出，适当酸处理后，氧漂过程中中添加氨磺酸（ＳＦＡ），适当提高氧漂压力（１．０ＭＰａ），延长漂白时间（７０分钟），可使未漂浆硬度（ＫＭｎＯ４值）降低率达５０％左右；白度从５１．７５％升高至７０．９％（ＳＢＤ）；粘度降低率为１６．６％，氧漂浆粘度为１０２０ｃｍ／ｇ。系统的Ｈ２Ｏ２漂白表明，氧漂浆在Ｈ２Ｏ２漂前采用Ｈ２ＳＯ４预处理具有很好的效果，Ｈ２Ｏ２     

多菌法培养窖泥初探

多菌法培养窖泥初探金星湖北襄樊市酿酒厂（０４１０２１）选用优质老窖泥为泥种，内蒙古轻工所的己酸菌种和汉逊酵母、球拟酵母等培养窖泥。己酸菌种、泥种的一、二级培养基：ＮａＡＣ０．７％、（ＮＨ＿４）＿２ＳＯ＿４０．０５％、Ｋ＿２ＨＰＯ＿４０．０４％，ＭｇＳ...     

淀积和掺杂方法对氧化锡薄膜气体灵敏度的影响

采用蒸发法、反应离子溅射法和等离子增强淀积法３种方法，在ＳｉＯ＿２－Ｓｉ衬底上淀积一层ＳｎＯ＿２薄膜，在这层薄膜内用反应离子溅射或蒸发法掺人微量Ａｌ．比较这些掺杂和未掺杂样品对氢气响应灵敏度的差别，研究了响应灵敏度差别与薄膜的微观结构和表面原子价态之间的关系．     

S—g—PEMA接枝淀粉的合成

研究了以玉米淀粉和甲基丙烯酸乙酯为原料，以ＫＭｎＯ４／Ｈ２Ｃ２Ｏ４引发体系合成Ｓ－ｇ－ＰＥＭＡ。ＳＥＭ和ＩＲ证明了产物的正确性，产物的接枝效率可达８０％以上。     

烟草施用亚硒酸钠的研究

土壤和叶面施用亚硒酸钠（Ｎａ＿２ＳｅＯ＿３）能显著提高烟叶的含硒量，叶面施用的利用率是土壤施用的几十倍。此外，叶面施用Ｎａ＿２ＳｅＯ＿３的时期不同，硒在各部位叶片的分布规律也不一样。苗期施用，下部叶片的含硒量高于上部叶片；旺长期施用，上部叶片的含硒量高于下部叶片；成熟期施用，各部位叶片的含硒量相似。在成熟期叶面喷施浓度为５～１５μｇ。Ｓｅ／ｍｌ的Ｎａ＿２ＳｅＯ＿３溶液，上、中、下部位叶片的含硒量为０．２０～０．５０μｇ．Ｓｅ／ｇ．ＤＷ（干重），平均０．４３μｇ．Ｓｅ／ｇ．ＤＷ，故可以生产出合乎需要的含硒烟叶。     

CO_2传感器的研究

采用ＮＡＳＩＣＯＮ（Ｎａ离子导体）与ＢａＣＯ＿３－Ｌｉ＿２ＣＯ＿３电极相结合的方式，使新型ＣＯ＿２传感器得到发展，据观察，其响应时间以及抗水湿性能都有了提高。对ＣＯ＿２浓度在１００～５×１０￣５ｐｐｍ这样宽的范围内，５００℃时测得的电动势与能斯特方程符合得很好。该元件几乎不受共存的Ｈ＿２Ｓ１００ｐｐｍ，ＮＯ＿２１００ｐｐｍ，ＣＯ１００ｐｐｍ，ＳＯ＿２１００ｐｐｍ，Ｃ＿２Ｈ＿５ＯＨ１００ｐｐｍ，ＣＨ＿４５０００ｐｐｍ以及ＮＨ＿３２０００ｐｐｍ的影响。电极材料在２０℃高湿状态下保持８００ｈ以上，其状态仍然没有大的变化．     

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