基于锥形量热仪的纤维集合体燃烧性能测试方法

为从物性角度更全面地研究纤维燃烧特性,快速科学的评估纤维燃烧性能和确定纤维复配方案,建立了利用锥形量热仪测试纤维集合体燃烧性能的一般性方法。通过分析影响纤维样品测试结果可重复性的因素,利用系列实验确定锥形量热仪测试纤维燃烧性能的测试条件参数如辐射强度、格栅遮盖率、纤维样品面密度等,并进一步通过实验对方法进行验证。研究结果表明：锥形量热仪测试纤维样品的最优参数分别为辐射强度75 kW/m2、格栅遮盖率25%、纤维样品面密度600 g/m²,该条件下测试得到的纤维样品的最大热释放速率（PHRR）的CV值最小,测试结果的可重复性最好;并且验证实验表明该方法具有较广的适应性和良好的灵敏度。     

散粮装卸系统斗式提升机内粉尘爆炸特征参数

针对散粮装卸系统斗式提升机机座中的粮食粉尘,在对其进行特性参数表征及热分解特性分析的基础上,开展了爆炸特征参数测试。结果表明,斗式提升机内粮食粉尘粒径在60～80μm的分布相对密集,中位粒径为75μm ,粉尘颗粒呈不规则状,有机物占总质量的80％以上,因而具有一定的爆炸危险性。粮食粉尘的爆炸下限浓度为70 g／m3,而特定条件下斗式提升机内的粉尘浓度明显高于该值,故存在较大的粉尘爆炸隐患,清扫积尘、防止产生可能的点火源是预防该类场所发生粉尘爆炸的有效手段。粉尘的最危险爆炸浓度为700 g／m3,最大爆炸压力约为0．5MPa,最大压力上升速率约为10MPa／s,因而在实际生产中,必须采取相应的爆炸泄压或抑制措施。     

大孔吸附树脂对麦胚肽的吸附特性研究

从大孔吸附树脂对麦胚肽的静态吸附率与解吸率考察了9种树脂的吸附性能，DA201—C大孔吸附树脂吸附特性优于其它8种树脂；吸附流速、麦胚肽的浓度及不同离子强度的样品溶液等对大孔吸附树脂动态吸附性能有影响；DA201-C大孔吸附树脂对麦胚肽的脱盐率为92．13％，麦胚肽的回收率为78．55％：利用不同浓度乙醇可将麦胚肽段按疏水性大小进行初步分离纯化，具有最大疏水性值的75％乙醇洗脱组分清除超氧阴离子自由基（听）的能力最强，其IC50为490．49μg/mL。     

基于主成分分析和判别分析的稻米产地溯源

以提高矿物元素对大米产地溯源的稳定性和准确性,找寻表征小范围相似地域特性的溯源指标为目的。采用原子吸收光谱法（AAS）分析吉林省松原市三大主产区10个产地100个大米样品中的矿物元素含量,对所得矿物元素含量数据进行差异分析、判别分析、主成分分析和聚类分析。试验结果为实现了松原市三大主产区大米产地溯源,正确判别率为100%。松原市矿物元素溯源指标的筛选主成分分析结果：第一主成分主要由Zn、K、Mg、Na、Ca和Mn 等6种元素构成,贡献率最大,占47.176%。判别分析验证主成分分析和聚类分析的准确性,其正确判别率为100%。利用矿物元素实现小范围产地溯源,并获得吉林省松原市溯源指标：Zn、K、Mg、Na、Ca和Mn 6种元素。     

基于主成分分析和判别分析的大米产地溯源

以提高矿物元素对大米产地溯源的稳定性和准确性,找寻表征小范围相似地域特性的溯源指标为目的。采用原子吸收光谱法(AAS)分析吉林省松原市三大主产区10个产地100个大米样品中的矿物元素含量,对所得矿物元素含量数据进行差异分析、判别分析、主成分分析和聚类分析。试验结果实现了松原市三大主产区大米产地溯源,正确判别率为100%。松原市矿物元素溯源指标的筛选主成分分析结果:第一主成分主要由Zn、K、Mg、Na、Ca和Mn等6种元素构成,贡献率最大,占47.176%。判别分析验证主成分分析和聚类分析的准确性,其正确判别率为100%。利用矿物元素实现小范围产地溯源,并获得吉林省松原市溯源指标:Zn、K、Mg、Na、Ca和Mn 6种元素。     

紫外光引发丙烯酰胺接枝改性棉织物亲水性的研究

以丙烯酰胺（AM）为接枝单体,采用紫外光（UV）接枝的方法对棉织物进行接枝改性,采用傅立叶红外光谱仪（FTIR）、有机元素分析仪和热重分析（TGA）对接枝样品进行表征,研究了单体浓度、光引发剂浓度、光照时间等因素对接枝率的影响。红外光谱分析和有机元素分析证明AM接枝到棉织物上。接枝率随着接枝单体浓度和光照时间的增加而增大,并随着引发剂二苯甲酮（BP）的浓度的增加先增大后减小;AM浓度为20wt%,BP浓度为3wt%,接枝反应40min,接枝率达到24.05%。接枝改性的棉织物,亲水性得到提高,接枝棉织物的亲水性随接枝率的增加而增大。     

龙井绿茶茶多酚提取工艺研究

为了提高茶多酚的得率和纯度,以龙井绿茶为原料,对茶多酚进行乙醇溶液提取、超声波和微波辅助提取。醇提的最佳条件为乙醇浓度50％,浸提4次,每次45min,温度为70℃,液固比为20：1,最大浸提率为24．45％。微波辅助提取最佳条件为预浸30min,乙醇浓度40％,微波解冻档浸提4min,浸提2次,液固比为40：1,最大浸提率为24．70％。超声波辅助浸提最佳条件为乙醇浓度80％,浸提温度50℃,浸提时间25min,浸提2次,液固比为14：1,最大浸提率为24．72％。结果表明：微波与超声波提取率稍高于醇提,但三者差别不大。     

激光诱导击穿光谱快速定量检测橘子中 铅含量的初步研究

目的利用激光诱导击穿光谱技术对橘子中铅含量进行快速定量检测。方法将普通的橘子样品进行铅溶液污染处理,利用原子吸收法测定样品中铅元素含量作为参考浓度,通过分析橘子中铅元素的激光诱导击穿光谱特征谱线,结合NIST标准数据库,得出铅元素的激光诱导击穿光谱显著的波长为363.958 nm、368.348 nm、405.783 nm,并确定以405.783 nm作为定量分析铅元素特征波长的方法。结果分析实验中的不同浓度样品的光谱信息,拟合得到铅元素的LIBS特征谱线强度和铅元素浓度的定量分析曲线,其中拟合曲线的相关系数为0.98195,分析定标模型得出该模型不适用于浓度小于10μg/g样品,根据检出限公式得到检测限(D.L)的值为12.98μg/g。结论研究结果表明该激光技术在农产品重金属检测以各种样品中的元素含量检测方面具有很大的前景。     

实验碾米机性能测试

采用不同类别、不同粒型的稻谷试样对国内使用的实验碾米机进行实验测试,结果表明,不同仪器差异显著,同一样品用不同型号的碾米机,其整精米率差值,7个籼米的差值平均为11.05%.单一样品不同型号碾米机整精米率最大差值为9.23%,最小差为5.38%.说明不同型号碾米机对整精米率测定结果有较大影响.     

UPLC-UV法快速测定烟草中游离茄尼醇的含量

为了简化烟草样品的前处理步骤,采用甲醇直接萃取烟草样品得到甲醇萃取液,优化超高效液相色谱的测试条件,测定了甲醇萃取液中的茄尼醇含量.结果表明:①最佳萃取条件为:萃取溶剂为甲醇,萃取温度25℃,萃取时间20 min;②茄尼醇工作曲线的浓度范围为10～200 mg/L时,质量浓度与峰面积具有良好的线性关系,相关系数为0.9997;③方法的检出限为0.054 mg/L,相对标准偏差为2.1％,平均回收率为105.5％.该方法可以快速、简便、准确地测试烟草中游离茄尼醇的含量.     

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.     

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     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press