仓房气密性改造与害虫熏蒸防治技术探索

中央储备粮湖州直属库对部分仓房进行了气密性改造,并对改造后的仓房进行了实仓磷化氢熏蒸防治储粮害虫试验。试验表明:通过实施一系列气密性改造措施,可以显著提高储粮仓房的气密性,延长磷化氢气体较高浓度水平的保持时间,延迟补药时间,甚至无需补药,而最终可以有效杀死仓内的储粮害虫,实现低剂量熏蒸。     

浅谈影响磷化氢熏蒸效果的几种因素

利用磷化铝、磷化锌、磷化钙产生磷化氢气体防治储粮害虫,在我国已有20多年的历史.现在磷化氢不仅用于原粮的熏蒸,而且还扩大到成品粮、饲料粮及其它储藏物的熏蒸,磷化氢已是当前储粮害虫防治中的一个重要武器.但是,近几年来,有不少地方出现熏蒸失效或熏蒸不彻底的现象,很多粮食工作者(特别是基层保管员)都将它归咎为害虫抗药性的作用.其实不尽然.据笔者多次细致的调查,发现一些粮库熏蒸不彻底的主要原     

高大浅圆仓磷化氢混合环流熏蒸杀虫技术研究

对储粮线27.15m、内径25.00m高大浅圆仓磷化氢混合环流熏蒸技术方案和混合环流熏蒸技术在进口大豆储藏中的应用进行了研究。结果表明:通过对环流通风时间的合理控制,可以减少不必要的通风,减少熏蒸药剂用量,增加熏蒸杀虫效力;与常规熏蒸相比,混合环流熏蒸可以在短时间内使熏蒸仓内磷化氢气体浓度分布均匀,并且可以节约熏蒸费用34.6%,具有较好的经济效益。     

华中储粮区浅圆仓储粮害虫防治技术研究

研究了在华中储粮区利用磷化氢防治浅圆仓小麦储粮害虫的效果、磷化氢气体浓度变化规律等,总结了浅圆仓储粮害虫防治的技术要点,为指导浅圆仓储粮害虫防治工作提供技术支撑。     

高大平房仓磷化氢熏蒸及散气作业过程安全防护距离研究

近年来由于熏蒸散气而产生的仓内安全事故引起了行业乃至社会各方的高度关注,但熏蒸散气阶段的作业安全研究较少,相关隐患尚未被深入研究以及重视。在实仓实验中,对高大平房仓磷化氢熏蒸和散气过程仓房内外环境空气中磷化氢浓度进行现场检测,探讨熏蒸、散气作业过程的有效安全防护距离以及防护措施,研究结果为防范熏蒸作业安全事故、减少或避免发生人身伤害和经济损失提供依据。研究结果表明,安全防护距离与仓内(粮堆内)磷化氢气体浓度大小有关,不能完全以固定的安全防护距离作为判定是否安全的依据,接近熏蒸散气区域前必须检测磷化氢浓度。     

立筒仓磷化氢环流熏蒸杀虫试验

本试验在封闭的立筒仓内粮堆表层投放磷化铝片剂，通过立筒仓多用途管道系统（可进行储粮机械通风降温、降水和多种药剂环流熏蒸）进行环流熏蒸。磷化氢气体在仓内各部位分布均匀无死角，杀虫效果达到１００％。熏蒸操作简便、安全，耗能源少，并且节约费用。     

浅圆仓熏蒸过程中磷化氢扩散和分布特性研究

在直径27 m、装粮线高度18 m,仓内体积12 000 m3,压力半衰期为600 s的浅圆仓中,采用粮面药袋投药和两侧梳型风道环流熏蒸,研究了浅圆仓粮堆纵向和横向上磷化氢扩散及分布特性,评估了粮堆内部不同部位磷化氢Ct值。结果表明,浅圆仓粮堆内磷化氢浓度衰减阶段的浓度呈指数下降趋势,磷化氢浓度衰减阶段浓度和时间符合指数模型C=1 061.7e-0.071t模型（R2=0.917 1）其中C为磷化氢浓度,mL/m3;t为熏蒸时间,d;e为自然指数）。环流熏蒸系统促进粮堆内磷化氢的均匀分布,可以避免因过高浓度造成的不利,但粮堆内磷化氢在不同区域浓度仍然存在差异,且难以避免熏蒸死角的存在。在浅圆仓熏蒸初期,从横向方向看,磷化氢在中轴聚集,浓度以中轴为中心向仓壁递减;从纵向方向看,磷化氢从上到下浓度依次降低,粮堆内表层和中轴处磷化氢浓度相对较高。在磷化氢浓度衰减阶段,粮堆中间层和中轴处磷化氢浓度相对较高。浅圆仓环流熏蒸系统A面管、B面管和仓底取样口Ct值低于平均浓度累积值,存在害虫防治隐患。在实际工作中可通过优化改进环流熏蒸风道可以改变粮堆内磷化氢气体的分布。     

立筒仓储粮熏蒸技术研究

本文介绍了在不同容量的立筒仓内安装的四种不同形式的管道系统，有用于熏蒸杀虫的专用管道；也有适合各种类型立筒仓进行溴甲烷、磷化氢环流熏蒸杀虫，熏蒸杀灭小麦矮腥黑穗病菌，熏蒸杀灭假高梁活性，气控储粮，机械通风降温，降水的多功能共用管道系统。共用管道系统只安装一套管道，能满足熏蒸杀虫、灭疫和安全储粮多种用途需要，使用方便、有效、安全、节约费用。     

浅圆仓磷化氢熏蒸方法的研究

在浅圆仓中进行了磷化氢熏蒸试验研究，对实验仓进行密封处理，经测试实验仓压力由500Pa降至250Pa的时间都在60s以上，用两种磷化氢熏蒸方法，借助环流熏蒸装置进行了熏蒸杀虫试验，磷化铝用药量为1．8－3．4g/m^3，磷化氢仓外发生器分两次施药，试验结果表明：磷化氢浓度保持100m/kg以上时间为15d以上，保持70mg/kg以上时间为17d以上，达到了环流熏蒸的技术要求，粮堆内的储粮害虫均被杀死，取得了 良好的杀虫效果。     

储粮害虫防治技术进展与展望（上）——熏蒸杀虫剂篇（网络首发、推荐阅读）

国内外粮食行业主要使用的熏蒸杀虫剂有两种：磷化氢和硫酰氟。磷化氢是“王牌”储粮熏蒸杀虫剂,硫酰氟主要作为磷化氢抗药性管理用药,两者有一定的互补性。针对我国储粮害虫防治技术应用现状、防控面临的问题和挑战,调研和梳理了国内外储粮熏蒸杀虫剂磷化铝（磷化氢）的基本技术特性、主要生产企业、产销情况、应用技术、残留问题、残渣处置方法、及其应用主导地位;结合国内外情况,综述了硫酰氟熏蒸杀虫技术特性、与磷化氢的关系、需求量、应用特点及存在问题,提出了要系统开展硫酰氟熏蒸杀虫技术研究、深入开展其对环境影响研究的建议和必要性,以遵从“绿色、生态、经济、高效”理念,为我国储粮害虫综合防治科学技术发展提供参考。     

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.     

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.     

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.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Influence des ions sur le pouvoir hydratant de l'ure e: e tude sur peau de porc ex vivo

This study deals with the influence of ions (NaCl and MgSO4) in a W/O emulsion containing 10% urea. Moisturization kinetics are assessed by corneometry on pig skin ex vivo. The formula's influence on urea penetration is measured by infrared spectrometry with an ATR device and the stripping method. Corneometry and spectroscopy were chosen to record simultaneously the hydratation levels and urea localization into superficial cell layers. Urea crystallization after evaporation of emulsions and aqueous solutions is described. Results show that urea does not hydrate nor penetrate when applied to the skin through an aqueous gel. In a W/O emulsion, sodium chloride increases the ability of urea to moisturize without improving penetration. In vitro urea crystallization is disturbed by sodium chloride or magnesium sulphate for solutions and emulsions. This stabilization by ions is correlated with good moisturization values. The stabilization of urea in the solute state provided by ions increases its water epidermal binding capacity without enhancing penetration.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.