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1.
A broad elemental profile incorporating 54 elements (Li, Be, B, Na, Mg, Al, P, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Rb, Sr, Y, Mo, Pd, Ag, Cd, Sn, Sb, Te, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Er, Tm, Yb, Re, Ir, Pt, Au, Hg, Tl, Pb, Bi and U) in combination with δ(2) H, δ(13) C, δ(15) N and δ(18) O was used to characterise the composition of 62 green arabica (Coffea arabica) and robusta (Coffea canephora) coffee beans grown in South and Central America, Africa and Asia, the four most internationally renowned areas of production. The δ(2) H, Mg, Fe, Co and Ni content made it possible to correctly assign 95% of green coffee beans to the appropriate variety. Canonical discriminant analysis, performed using δ(13) C, δ(15) N, δ(18) O, Li, Mg, P, K, Mn, Co, Cu, Se, Y, Mo, Cd, La and Ce correctly traced the origin of 98% of coffee beans. Copyright ? 2012 John Wiley & Sons, Ltd.  相似文献   

2.
《Physics of Atomic Nuclei》2004,67(11):2054-2057
NESTOR is a submarine high-energy muon and neutrino telescope, now under construction for deployment in the Mediterranean close to Greek shores. The first floor of NESTOR with 12 optical modules was deployed successfully in March 2003 together with the electronics system. All systems and the associated environmental monitoring units are operating properly and data are being recorded. The status of the NESTOR project is presented. We outline briefly the construction of the deepwater neutrino telescope, properties of the NESTOR site, infrastructure of the project, the deployment of the first floor, and its current operation. The first data are presented and plans for the next steps are summarized. From Yadernaya Fizika, Vol. 67, No. 11, 2004, pp. 2075–2078. Original English Text Copyright ? 2004 by Zhukov, Aloupis, Anassontzis, Arvanitis, Babalis, Ball, Bezrukov, Bourlis, Butkevich, Chinowsky, Christopoulos, Darsaklis, Dedenko, Elstrup, Fahrun, Gialas, Goudis, Grammatikakis, Green, Grieder, Karaevsky, Katrivanos, Keussen, Kiskiras, Knutz, Korostylev, Komlev, Kontakxis, Koske, Learned, Ledenev, Leisos, Limberopoulos, Ludvig, Makris, Manousakis-Katsikakis, Makropoulos, Matsuno, Mielke, Mihos, Minkowski, Mironovich, Mitiguy, Nounos, Nygren, Papageorgiou, Passera, Politis, Preve, Prybylsky, Rathley, Resvanis, Rosen, N. Schmidt, Th. Schmidt, Siotis, Shnyrev, Sopher, Staveris, Stavrakakis, Stokstad, Surin, Tsagli, Tsirigotis, Tsirmpas, Tzamarias, Vasiliev, Vaskin, Voigt, Vougioukas, Voulgaris, Zakharov, Ziabko. The authors represent the NESTOR Collaboration This article was submitted by the authors in English.  相似文献   

3.
Oak Ridge National Laboratory, Tennessee, USA, ORLaND is a collaboration proposing a major neutrino physics facility at the Spallation Neutrino Source (SNS) at the Oak Ridge National Laboratory. An underground bunker is proposed adjacent to the first target station of the SNS. The bunker is designed to house one large detector (2000 t) and a number of smaller (200 t) detectors. A comprehensive program of neutrino experiments is being developed that could span the lifetime of the Spallation Source. From Yadernaya Fizika, Vol. 63, No. 6, 2000, pp. 1082–1086. Original English Text Copyright ? 2000 by Avignone III, Anderso, Awes, Berridge, Bilpuch, Britton, Bryan, Bugg, Burman, Busenitz, Carter, Chatterjee, Cianciolo, Cochran, Cohn, Danilov, De-Brackeleer, Degtiarenko, Efremenko, Elaasar, Fazely, Frank, Gabriel, Gould, Gudkov, Gunasingha, Handler, Hart, Imlay, Jagadish, Kamyshkov, Khosrovi, Koetke, Lane, Manweiler, Metcalf, Mezzacappa, Mo, Nosik, Nummaker, Nussinov, Piepke, Plasil, Reidy, Rosenfeld, Smith, Stancu, Stanislaus, Steinberg, Svoboda, Tashakkori, Tornow, Van Dalen, Walker, Watson, Wintenberg, Wolf, Wright, Zel’dovich, Zhang. This article was submitted by the authors in English.  相似文献   

4.
《Physics of Atomic Nuclei》2003,66(3):503-508
We review the present status of the Baikal neutrino experiment. The structure and parameters of the neutrino telescope NT-200, which was put into operation in April 1998, are described. Selected methodological results are presented. Physics results cover separating up-going muons from atmospheric neutrinos, searches for neutrino events from WIMP annihilation, searches for magnetic monopoles, and high-energy neutrinos. From Yadernaya Fizika, Vol. 66, No. 3, 2003, pp. 530–535. Original English Text Copyright ? 2003 by Balkanov, Belolaptikov, Bezrukov, Budnev, Chensky, Danilchenko, Dzhilkibaev, Domogatsky, Fialkovsky, Gaponenko, O. Gress, T. Gress, Il'yasov, Klabukov, Klimov, Klimushin, Koshechkin, Konischev, Kulepov, Kuzmichev, Kuznetsov, Lubsandorzhiev, Micheev, Milenin, Mirgazov, Moseiko, Osipova, Panfilov, Pan'kov Parfenov, Pavlov, Pliskovsky, Pokhil, Poleshuk, Popova, Prosin, Rosanov, Rubzov, Semenei, Spiering, Streicher, Tarashansky, Vasiliev, Wischnewski, Yashin, Zhukov. This article was submitted by the authors in English.  相似文献   

5.
《Physics of Atomic Nuclei》2002,65(7):1222-1227
The cross section for the process e + e K L 0 K S 0 is measured by using approximately 1000 events recorded by the CMD-2 detector at the VEPP-2M collider in the energy range from 1.05 to 1.38 GeV. __________ Translated from Yadernaya Fizika, Vol. 65, No. 7, 2002, pp. 1255–1260. Original Russian Text Copyright ? 2002 by Anashkin, Aulchenko, Akhmetshin, Banzarov, Barkov, Baru, Bashtovoy, Bondarev, Bondar, Bragin, Gabyshev, Gorbachev, Grebeniuk, Grigoriev, Dhawan, Zverev, Ignatov, Kazanin, Karpov, Koop, Krokovny, Kuzmin, Kurdadze, Logashenko, Lukin, Lysenko, Mikhailov, Nesterenko, Okhapkin, Polunin, Popov, Roberts, Root, Ruban, Ryskulov, Sibidanov, Sidorov, Skrinsky, Smakhtin, Snopkov, Solodov, Stepanov, Sukhanov, Thompson, Fedotovich, Khazin, Hughes, Chernyak, Shamov, Shatunov, Shwartz, Eidelman, Yudin. Dedicated to Isai Isidorovich Gurevich—Teacher and marvelous man  相似文献   

6.
Vacuum arc ion charge-state spectra have been measured for a wide range of metallic cathode materials. The charge-state distributions were measured using a time-of-flight diagnostic to monitor the energetic ion beam produced by a metal vapor vacuum arc ion source. Data were obtained for 48 metallic cathode elements: Li, C, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn Fe, Co, Ni, Cu, Zn, Ge, Sr, Y, Zr, Nb, Mo, Pd, Ag, Cd, In, Sn, Ba, La, Ce, Pr, Nd, Sm, Gd, Dy, Ho, Er Yb, Hf, Ta, W, Ir, Pt, Au Pb, Bi, Th, and U. The arc was operated in a pulsed mode with pulse length 0.25 ms: arc current was 100 A throughout. The measured distributions are cataloged and compared with earlier results. Some observations about the performance of the various elements as suitable vacuum arc cathode materials are also presented  相似文献   

7.
Abstract

A microwave-assisted digestion procedure has been developed for the treatment of silicone oil samples. Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the concentration level of 40 trace element impurities, like Li, Na, Mg, Al, P, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Sr, Rb, Zr, Nb, Mo, Ag, Cd, Sn, Sb, Ba, La, Ce, Nd, Hf, W, Au, Pb, Hg, Th, Bi and U in these samples, having obtained average relative standard deviation values of 9.6%. The methodology developed has been tested by recovery studies on different natural samples spiked with known amounts of Mg, Cr, Mn, Fe, Zn and Pb at concentration levels of 10, 0.5, 5, 5, 10 and 1 μg g?1 and recovery percentage values varies from 97 to 105 %.  相似文献   

8.
ICP-AES法分析灵芝中的微量元素   总被引:2,自引:0,他引:2  
采用湿法消解,ICP-AES法分析不同原料的两种灵芝子实体、灵芝子实体根部、灵芝混合物、灵芝破壁与不破壁孢子粉中的20种微量元素,Al,As,Ca,Cd,Co,Cr,Cu,Fe,Ce,Hg,K,Mg,Mn,Na,Ni,P,Pb,S,Se,Zn的含量.结果表明:不同灵芝样品中的矿物元素含量很丰富,其中元素K,Ca,Mg,Fe,Zn,P,S含量较高,主要存在的微量元素有:Cu,CO,Cr,Ni;具有潜在生理毒性的元素为Al,As,Hg,Pb,Cd,抗癌功效元素Se和Ge在所有灵芝样品中并未测得.孢子粉中重金属元素含量相对灵芝原料更低些,灵芝混合物中有添加的功效元素Fe和se,灵芝根部切片样品中的Ca,Cu,Zn含量与其他样品都要高,不同品种的灵芝原料中的微量元素含量存在一定的差异性.  相似文献   

9.
Instrumental neutron activation analysis was used for the determination of Na, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Rb, Sb, Cs, La, Ce, Sm, Eu, Dy, Yb, Lu, Hf, Ta, Pa, and U in bitter cola (Garcinia cola), Tatassai (Capsicum spp), sweet pepper (Capsicum annum), chillies (Capsicum spp.), alligator pepper (Aframomum melagueta) and onions (Allium caps) which are the major Nigerian stimulants.  相似文献   

10.
密封消解ICP-AES和ICP-MS测定中日两国茶叶中23种矿质元素   总被引:18,自引:4,他引:14  
收集了13种中国茶叶和6种日本茶叶,在进行密封消解后,采用电感耦合等离子体发射光谱法(ICP-AES)和电感耦合等离子体质谱法(ICP-MS)测定了茶叶中Al,Ba,Ca,Cd,Ce,Co,Cr,Cs,Cu,Fe,La,Mg,Mn,Na,Ni,Pb,Rb,Sb,Sr,Th,U,Y和Zn等23种矿质元素的含量,并用茶叶标准参考物质(GBW07605)评价了分析方法的准确度。研究结果表明:密封消解有助于获得较为准确的茶叶中矿质元素含量的分析结果;与日本茶叶相比,中国茶叶中Cd,Co,Cr,Cs,Fe,Pb,Rb,Sb,Th,U和Zn等元素含量显著偏高(P<0.05),预示大气重金属污染程度中国较日本严重。另外,还发现茶叶中一些矿质元素含量之间有很强的线性相关性。  相似文献   

11.
火焰原子吸收光谱法测定锁阳中15种金属元素含量   总被引:35,自引:0,他引:35  
采用浓硝酸-高氯酸(φ∶4∶1)常压微沸条件下消解锁阳样品,应用火焰原子吸收法测定了锁阳中的金属元素Na, K, Mg, Ca, Cu, Zn, Fe, Co, Ni, Mn, Pb, Cr, Cd, Au, Ag含量,研究了测定不同元素的仪器最佳工作条件、方法的准确性和精密度。结果表明,锁阳中Na, K, Mg, Ca, Fe, Zn,Cu, Mn, Pb, Ni, Ag含量分别为13 572.0, 14 260.0, 358.3, 168.3, 238.5, 19.4, 5.9, 3.4, 2.6, 1.3, 0.4 μg·g-1, Co, Cr, Cd, Au未检出。方法的加标回收率为97.8%~104.5%, 相对标准偏差(n=9)为0.2%~5.0%。测定方法简单易行,方便快捷,结果令人满意。  相似文献   

12.
Twenty‐three paintings by Henrique Pousão—a 19th century Portuguese painter—belonging to the collection of Museu Nacional Soares dos Reis, Porto, Portugal, were analysed by Raman microscopy. The fine focus of a 100× objective allowed the visualisation and individual identification of small grains. As a result, thirty‐seven compounds, namely, anatase, barium white, basic lead sulfate, brochantite, cadmium red, cadmium yellow, calcium carbonate, carbon‐based black, celadonite, chrome green, chrome orange, chrome yellow, cobalt blue, cochineal lake, copper sulfide, emerald green, iron(III) oxyhydroxide, iron(III) oxide, kaolinite, lead antimonate yellow, lead carbonate, lead white, lead sulfate, madder lake, malachite, Prussian blue, quartz, realgar/pararealgar, red lead, rutile, Scheele's green, strontium yellow, ultramarine blue, vermilion, viridian, zinc white and zinc yellow, were identified. Not all these compounds are pigments; some are extenders, others trace components and others probably products of reactions between pigments. Special attention was given to the Raman characterisation of celadonite, chrome orange, basic lead sulfate and lead antimonate yellow. Complementary techniques were used to confirm the identities of certain pigments and to characterise reference samples. Pousão, whose work has not previously been studied spectroscopically, was found to have used a remarkably wide range of pigments over his painting periods, without showing significant preference for any particular set of pigments. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

13.
Fractionation of elements in food is essential for understanding and prediction of its bioavailability, effects, and toxicity. In the present study, an analytical fractionation scheme for milk samples was developed for the common elements, such as Fe, Cu, Zn, Mn, Mg, Ca, Cr, Ni, Mo, Al, Pb, Sn, V, Ba, Co, and Cd. For this purpose, applying a sequential separation procedure, the protein, lipid, and serum fractions were obtained separately. The recovery percentages were in the range of 96.3–104.0 for the separation of fractions in the synthetic milk. The results achieved in the paper were compared with reported literature data. Additionally, the fractionation pattern for each metal studied was different relating to the origin of milk. Although there were some exceptions, it was seen that Fe, Cu, and Al preferred to be in protein fraction; however, Zn, Mn, Mg, Ca, Cr, Ni, and Mo preferred to be in serum fraction.  相似文献   

14.
Instrumental neutron activation analysis (INAA) was used for the determination of major, minor and trace elements in samples of bottom sediments of the inflows of the Selenga river basin to assess the impact of the contamination from the industrial complex Erdenet and other industrial enterprises in Mongolia. A total of 42 elements (Na, Mg, Cl, K, Ca, Al, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Sr, Rb, Sr, Zr, Nb, Sb, Cs, Ba, La, Ce, Nd, Sm, Eu, Tb, Dy, Tm, Hf, Ta, W, Au, Hg, Th, and U) was determined by combination of conventional and epithermal neutron activation analysis at the IBR-2 reactor, FLNP JINR, Dubna. For the first time such a large set of elements was used for characterization of the bottom sediments as accumulating media which may reflect industrial contamination of the water basin. The concentrations of heavy metals and other trace elements in the samples from three inflows of the Selenga river basin were compared with data from the previous studies. It was shown that the industrial zone of the Erdenet Mining Corporation (EMC) and gold mining zone Zaamar are the sources of strong environmental contamination. The concentrations of Cu and Sb determined in sediment samples of the River Khangal and Govil near the EMC exceed average crustal rock and soil values by factors of 50 and 15, respectively. In the area of the gold mining zone Zaamar concentrations of Au, As, and Sb exceed crustal rock and soil values by factors of 4, 25, and 6, respectively. The relatively high levels of As, V, Zn, V, and Sr in the sediments of the studied rivers are obviously due to the discharges of untreated wastewater of desalination plant, electrical power station, textile industry and mining activities as well as domestic wastewater.  相似文献   

15.
使用电感耦合等离子体原子发射光谱(ICP-AES)和原子荧光光谱法(AFS)分别对内蒙古自治区兴和县180名农村育龄妇女头发中21种矿物元素(铝,硼,钡,钙,镉,钴,铬,铜,铁,镁,锰,钼,镍,铅,硒,硅,锡,锶,钛,钒和锌)的含量及年龄、生育史及饮食习惯等对其产生的影响进行了研究。结果表明,大多数矿物元素(硼,镉,铬,钴,铜,铁,镁,锰,钼,镍,铅,硒,硅,锡,锶,钛,钒和锌)含量从青年组(18~29岁)到老年组(40~45岁)依次减少,而中年组(30~39岁)的钙,镁,锰、铅的含量最低。生育二胎的妇女钙,镁,锰,钼,镍,铅,锡,锶和锌含量最低,这可能与生育次数的增加有关,相关性分析证实钙,铅和锡与生育史有显著性相关。此外,饮食习惯也会影响头发中矿物质元素的含量。经常食用酸菜会导致锌,铁,铜,锰,锶含量水平较低,但钼,铅和硒含量水平较高。而且,锌和硒含量随肉类摄入频率增加而增加。规律性摄入蔬菜会增加硅的含量。同时,经常食用水果会增加锰,镍和钛的含量水平。因此,该研究为解决不均衡饮食习惯盛行的农村地区生育和妇女健康提供基础数据和有用的信息。  相似文献   

16.
天然杂质对黄铁矿的电子结构及催化活性的影响   总被引:2,自引:0,他引:2       下载免费PDF全文
李玉琼  陈建华  郭进 《物理学报》2011,60(9):97801-097801
采用密度泛函理论和平面波赝势方法对含天然杂质黄铁矿的电子结构和光学性质进行了计算,并讨论了二十种天然杂质:钴、镍、砷、硒、碲、铜、金、银、钼、锌、铊、锡、钌、钯、铂、汞、镉、铋、铅和锑,对黄铁矿催化活性的影响.结果表明在过渡金属杂质中,杂质能级主要由它们的d轨道产生,而在主族金属及非金属杂质中,杂质能级主要由它们的s或p轨道产生.含铜、钼、砷、金、银或镍的黄铁矿对氧的还原的电催化能力增强.除锌、钼、钌、砷、锑、硒和碲外,其余杂质能增强黄铁矿表面俘获电子的能力,使光生电子和空穴复合的概率减小.光学性质计算表 关键词: 天然黄铁矿 杂质 电子结构 光学性质  相似文献   

17.
采集了石河子城区32个站点的道路尘土样本,测定了样品中10种非常规监测微量元素(B,Be,Bi,Co,Ga,Li,Sb,Sn,Tl,V)的含量。并采用地积累指数法、元素相关性分析和主成分分析法对尘土中的微量元素污染程度和来源进行了分析。结果表明:道路尘土中微量B,Be,Bi,Co,Ga,Li,Sb,Sn,Tl和V的平均含量分别为41.11,1.68,0.52,13.58,36.26,24.91,3.37,3.64,0.42,72.66 mg·kg-1。其中,Co,Li和Tl的平均含量均低于新疆土壤元素背景值,B,Be和V的平均含量和新疆土壤元素背景值相似,Bi,Ga,Sb和Sn的平均含量高于新疆和世界土壤元素背景值。地积累指数计算结果表明:B,Be,Co,Ga,Li,Tl和V污染级数为0,说明无污染,而Sb,Bi和Sn污染较为严重(污染等级分别为2,1,1)。元素相关性分析和主成分分析多元统计方法计算结果表明,Bi,Co,Sb和Tl主要是人为来源,B,Be,Li和V主要是自然来源,而Ga和Sn可能受自然因素和人为因素的共同影响。  相似文献   

18.
应用电感耦合等离子体原子发射光谱法(ICP-AES)建立了定量分析江西白酒中As,Ba,Co,Ni,Cu,Be,Sr,Cr,Mn,Li,P,Se,Pb,Bi,Cd,B,Zn,Mg,Fe,K,Na,Ca,Al等23种微量元素的新方法。考察了不同地域生产的白酒以及同一厂家生产的不同酒精度和品质白酒中微量元素含量的差别。白酒经少量硝酸消化,样品消解完全,可以满足ICP-AES检测的要求。结果的相对标准偏差为0~5.81%,加标回收率为90.5%~107.6%,方法具有较好的准确度和精密度。研究结果可作为进一步探讨白酒质量与微量元素之间关联性的参考。  相似文献   

19.
Synchrotron radiation X-ray fluorescence analysis is used to determine for the first time the absolute content and biological accumulation coefficients for a set of 21 chemical elements (K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Zr, Nb, Y, Mo, and Pb) in the fruits, leaves, bark, roots, and root nodules of the sea buckthorn (Hippophae rhamnoides L. ssp. mongolica Rousi). It is found that all sea buckthorn tissues accumulate Ti, Nb, Cr, and Zr more intensively than the global average for terrestrial phytomass. On the other hand, none of the examined parts of the sea buckthorn plants accumulated the toxic elements Pb and As.  相似文献   

20.
抗缺氧藏药中微量及宏量元素的测定   总被引:6,自引:0,他引:6  
用HNO3-HClO4(4∶1) 混酸作消化液对红景天胶囊、安神散、五味石榴散、章松八味沉香散、十六味杜鹃散、二十五味余甘子丸、二十五味竹黄胶囊、十五味龙胆丸、秘诀清凉散、七十味珍珠丸、八味沉香散、六味丁香散和七味葡萄散等13种抗缺氧藏成药进行消化,采用火焰原子吸收分光光法测定了其中银、铝、镉、钴、铬、铜、铁、汞、镁、锰、镍、铅、锡和锌等14种微量及宏量元素的含量。结果表明,抗缺氧藏成药中含有比较丰富的铁、镁、铜、铬、锌及锰等微量元素。为探讨微量、宏量元素与藏成药抗氧化作用之间的关系提供了有用的数据。  相似文献   

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