微波消解-ICP-OES法测定4种孜然粉中的矿质元素

选取市售4种孜然粉为研究对象,采用浓HNO3/H2O2混合酸体系微波消解法制备样品,利用全谱直读电感耦合等离子体发射光谱法分析测定了样品中矿质元素的组成及含量。实验结果表明:从4种孜然样品中均检测出15种矿质元素,分别为K,Na,Ti,Al,B,Ba,Ca,Fe,Mg,Mn,P,S,Si,Sr,Zn,均未检出元素Tl,Sn,Cu以及Pb,Cd,Cr等重金属元素。常量元素K,Na,Ca,Mg,P,S,Si的含量均大于1000μg/g,微量元素Al,Fe的含量均大于100μg/g。研究结果为孜然的进一步研发提供了一定的理论依据和参考。     

翡翠中钠铬辉石的矿物学特征研究

采用电子探针、X射线衍射和吸收光谱分析研究翡翠中钠铬辉石的矿物学特征。结果显示,钠铬辉石与翡翠呈共生关系;其分子式为(Na0.83Ca0.02)(Cr0.78Al0.10Fe0.08Mg0.02)Si2.06O6;晶胞参数a=9.530A°,b=8.672A°,c=5.264A°,β=107.51°,V=414.88;密度为3.55g/cm3;钠铬辉石中Cr3 的晶体场跃迁决定了其具有深浅程度不同的绿色调。     

层脉土的命名、起源、形成与探测技术

(一) 命名层脉土是矿物族名,这族矿物是具有膨胀性的三层型结构硅酸盐,以前的分类被列入蒙脱石族。这族矿物的复合化学分子式如下: (1/2Ca,Na)_(0.7)(Al,Mg,Fe)_4[Si,Al]_8O_(20)(OH)_4·nH_2O 上述复合分子式表明:第一个括弧内,     

ICP-OES测定不同产地枇杷叶中20种元素

采用微波消解处理样品,建立ICP-AES测定Cu、Pb、Zn、Ni、Cd、Cr、Fe、Mn、Al、Ti、B、Sr、Mo、Ba、Co、Si、K、Na、Ca和Mg 20种元素质量浓度的分析方法。结果表明,各种元素在其线性范围内线性关系良好,r值为0.999 4～0.999 9,平均回收率为90.3%～96.7%, RSD5%(n=6)。ICP-OES可同时测定多种元素,方便快捷。通过ICP-OES检测研究18个不同产地枇杷叶样品中20种元素结果及相关规律, 20个元素含量高低顺序为Ca、K、Mg、Ba、Na、Sr、Fe、Zn、B、Mn、Cu、Al、Pb、Ni、Ti、Li、Mo、Cr、V和Cd。     

山东临朐红丝砚石的岩石化学特征及成因研究

对山东临朐红丝砚石进行全岩化学分析,发现红丝砚石的主量元素、微量元素、稀土元素等化学成分,并通过代表性元素比值来推测成因条件。结果显示,红丝砚石是CaO含量较高的碳酸盐岩,CaO含量为32.84%~53.10%,平均含量为47.69%。通过对红丝砚石主量元素的Mg/Ca、SiO2/(K2O+Na2O)、Al2O3/(K2O+Na2O)、Mn/Fe等比值,微量元素的Sr/Ba、Sr/Ca、Th/U等比值,稀土元素的LREE/HREE、[ω(La)/ω(Lu)]N、[ω(La)/ω(Yb)]N等比值以及δEu、δCe值和Yb/La—Yb/Ca图解推测矿床成因条件,得出红丝砚石为沉积成因的碳酸盐岩,属于滨海相、潮坪相浅水环境沉积。     

X射线荧光光谱法测定煤中常量和微量元素的实验分析

文章分析采用的样品是硼酸镶边垫底样品,样品经过压片制粉。然后通过Bruker-axs公司生产S4 Pioneer X射线专用荧光光谱仪来监测多煤田样品中的主要元素。第一种是Al2O3;第二种是Ca O;第三种是Fe2O3;第四种是K2O;第五种是Mg O;第六种是Na2O;第七种是Si O2。通过X射线来具体对上述元素进行测定。文章主要从X射线荧光光谱法的角度来测定煤中的常量以及微量元素。通过实验的方式来具体分析,希望通过文章的分析以及阐述能够有效的提升我国X射线荧光光谱法的应用以及推广,为我国元素测定做出一定的贡献。     

内蒙古达青牧场岩体岩石地球化学特征与构造环境

研究区位于西伯利亚板块与华北板块大陆边缘增生和碰撞过渡区以及古亚洲洋构造域与古太平洋构造域叠加转换的关键部位,区内岩浆岩分布广泛。文章通过对达青牧场岩体地球化学分析,结合区域地质背景,应用岩石化学方法,通过主量元素、微量元素和稀土元素的含量分析,得出一些经典图解确定岩体构造背景。主量元素分析表明岩体基性岩浆和酸性岩浆之间有过较强的物质交换,指示岩浆混合作用的存在。岩体正长花岗岩3个样品具高Si,富Al和Na,低Ca、Mg和Fe2O3,K2O/Na2O值大于1,A/CNK值为1.34-1.49;轻重稀土元素分馏强烈,轻稀土富集,重稀土亏损,Eu异常明显,表明为偏铝质的高钾钙碱性A型花岗岩。在微量元素相关判别图中,达青牧场岩体基本落入火山弧花岗岩(VAG)和同碰撞花岗岩(Syn-Colg)范围,总体表现为与碰撞有关的岛弧花岗岩,反映出花岗岩形成于俯冲带的构造环境。     

四川软玉猫眼的红外光谱和X射线粉晶衍射特征

通过对四川软玉猫眼进行 X射线粉晶衍射 (XRD)、傅立叶变换红外光谱 (FTIR)分析 ,结果表明 :四川软玉猫眼主要由透闪石矿物组成。利用 XRD计算的晶胞参数为 :α0 =0 .984 nm～ 0 .985 nm,ь0 =1.780 nm～ 1.782 nm,с0 =0 .5 2 7nm～ 0 .5 2 8nm,β=10 6 .13°～ 10 6 .35°。傅立叶变换红外谱带中 :36 70 cm- 1附近的吸收谱带归属透闪石结构中 OH伸缩振动的 A带。 96 0 cm- 1～ 110 0 cm- 1间的谱带归属 (Si4 O1 1 )的伸缩振动。 6 0 0 cm- 1～ 80 0 cm- 1范围内谱带归属 υs Si- O- Si振动 ,4 0 0 cm- 1～ 6 0 0 cm- 1范围内的谱带归属(Si4 O1 1 )的弯曲振动和 Mg- O伸缩振动。     

ICP-MS法快速测定水基胶中钾钠含量及其不确定度

电感耦合等离子体质谱法(ICP-MS)同时快速测定样品中钾(K)、钠(Na)元素含量,旨在控制产品质量稳定性。钾和钠的相关系数均在0.999以上,方法检出限分别为0.02 mg/L和0.03 mg/L,加标回收率分别是102.6%和104.6%,测定结果的相对标准偏差(RSD)均小于3%(n=6)。此方法具有操作简单、快速和准确等优点,适用于水基胶样品中K、Na含量的分析。此外,结果表明:K、Na测量结果的不确定度分别为0.22 g/kg和0.10 g/kg。而样品溶液测量是影响ICP-MS法测定水基胶中钾钠含量的主要不确定度来源。     

ICP-OES/ICP-MS测定15种鱼肉松中的30种矿物质元素含量

为科学评价市售鱼肉松的营养价值,建立了测定其样品中多元素含量的分析方法。采用HNO_3-H_2O_2-H_2O为消解体系经微波消解鱼肉松样品,电感耦合等离子体发射光谱法(ICP-OES)测定样品中的K、Na、Ca、Mg、Fe、Zn、Mn、P、Ti和Si,电感耦合等离子体质谱法(ICP-MS)测定样品中Li、B、Al、V、Cr、Ni、Co、Cu、As、Se、Sr、Mo、Cd、Sn、Sb、Te、Ba、Tl、Pb、Hg等30种矿质元素含量,各元素检出限低,线性关系良好。用该方法对生物标准物质扇贝(GBW 10024)进行测定,测定结果与证书参考值基本一致,对样品7进行了加标回收率试验,样品的各元素加标回收率均在88.5%~106.0%之间,说明该方法准确可靠。通过对零售和网购的15种鱼松样品的分析发现,鱼松样品中K、Na、Ca、Mg、Fe、Zn、Mn、P、Cu、Se、Sr、Mo等营养元素的含量较高。     

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