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1.
利用25 MeV/u 40Ar+Se中能重离子核反应, 制备包含24种元素在内的多重示踪剂, 通过对元素γ谱的分析, 研究了正常鼠和肿瘤鼠体内微量元素的分布及代谢。Mg, Sr, Ga, As, Sc, V, Cr, Mo, Co, Fe, Y, Zr, Nb和Ru等元素在肿瘤鼠的粪便和尿液中的排泄时间与正常鼠不同。 肿瘤鼠与正常鼠相比, Na, Mn, Fe和Co的排泄变化较大, 肿瘤鼠的排泄率较正常鼠高; 而Ca, Y, Zr和Mo的排泄率肿瘤鼠则较正常鼠低; 在正常鼠脏器、 组织和血液样品中测出了Na, Rb, Ga, Sc, As, Zn, V, Cr, Mn, Co, Fe、Y, Zr, Tc, Ru, Ag和In等17种元素, 肿瘤鼠检测出了除Zn和As之外的其它15种元素。 几乎所有的元素在正常鼠中的吸收均比肿瘤鼠高。 大部分元素分布在肝、 肾和毛皮以及实体瘤中, 而Fe和Na在肿瘤组织则没有检测到。 A radioactive multitracer solution of the 24 elements, e.g. Be, Na, K, Rb, Mg, Ca, Sr, Ga, As, Sc, V, Cr, Mn, Co, Fe, Zn, Y, Zr, Mo, Nb, Tc, Ru, Ag and In, was obtained from the nuclear reaction of 25 MeV/u 40Ar+Se with a series of chemical process. The multitracer solution was orally administered to normal and muscular tumour bearing mice of male Balb/c mice. Urine and faeces samples of mice were collected. The two group mice were sacrificed after 96 h. The uptake of 17 elements, Na, Rb, Ga, As, Sc, V, Cr, Mn, Co, Fe, Zn, Y, Zr, Tc, Ru, Ag and In, were simultaneously detected in normal mice while 15 elements, Na, Rb, Ga, Sc, V, Cr, Mn, Co, Fe, Y, Zr, Tc, Ru, Ag and In, were simultaneously detected in tumour bearing mice. Our results indicate that the majority of the detected elements were distributed in liver, kidney, pelt, tumour while a small fraction of the biotrace elements were distributed in heart and spleen (tumour bearing mice) in the two groups of mice. The higher concentrations of Fe, Na, Mn were detected in heart or kidney of normal mice. Na, Mn, Fe and Co showed better absorption in most tissues in the normal mice, except for Na and Mn in heart.  相似文献   

2.
制备了La,Ce,Nd,Sm,Eu,Gd,Dy微粒和纳米金,分别用La,Ce,Nd,Sm,Eu,Gd,Dy微粒替代部分的纳米金,研究了La-Au,Ce-Au,Nd-Au,Sm-Au,Eu-Au,Gd-Au,Dy-Au微粒分别对银染效果的影响及其紫外可见(UV-Vis)吸收光谱。与纳米金相比,La-Au,Ce-Au,Nd-Au,Sm-Au,Eu-Au,Gd-Au,Dy-Au微粒可延长银染后的斑点持续的时间,其中Nd-Au微粒的效果最好,斑点持续的时间为30 min,是纳米金的2.7倍;可大幅度加深斑点的颜色,其中Nd-Au,Sm-Au微粒的效果最好,用Nd微粒替代部分的纳米金,纳米金用量降低了80%,但还能提高银染法的灵敏度。在200~800 nm范围,La,Ce,Nd,Sm,Eu,Gd,Dy微粒和纳米金溶液的UV-Vis吸收光谱只有一个吸收峰,λmax分别为275,277,276,276,278,277,278和521 nm;La-Au,Ce-Au,Nd-Au,Sm-Au,Eu-Au,Gd-Au,Dy-Au微粒混合液的UV-Vis吸收光谱有两个吸收峰,λmax(RE)λmax(Au)分别为276和522 nm,276和522 nm,276和523 nm,276和523 nm,276和522 nm,276和522 nm,276和523 nm,纳米金和La微粒的吸收峰的波长发生了红移,Ce,Eu,Gd,Dy微粒的吸收峰的波长发生了蓝移,Nd,Sm微粒的吸收峰的波长不变,纳米金与稀土微粒可能有相互作用。  相似文献   

3.
ICP-AES测定青岛崂山绿茶中的微量元素   总被引:2,自引:0,他引:2  
采用HNO3-H2O2混合酸,密闭微波消解样品,应用ICP-AES测定青岛崂山绿茶中Al、Ca、Cd、Co、Cr、Cu、Fe、K、Mg、Mn、Na、Ni、Pb、Se、Sr、V和Zn等17种营养元素及重金属元素的含量。测定结果的相对标准偏差均小于3.50%,对17种元素的加标回收率在90.0%—110.2%之间,采用该方法测得的茶叶标准物质(GBW10016)的17种元素的值均在标准值范围内,方法准确度高。实验结果表明青岛崂山绿茶中含有大量对人体有益的元素包括Ca、Co、Cr、Cu、Fe、K、Mg、Mn、Na、Ni、Se、Sr、V和Zn等,另外也检测到含有Al,Cd和Pb等有毒、有害元素,但是含量很低,对人体的不利影响可以忽略不计。  相似文献   

4.
This is a summary of the beyond the Standard Model (including model building) working group of the WHEPP-X workshop held at Chennai from January 3 to 15, 2008. Participants: Neelima Agarwal, S K Agarwalla, C S Aulakh, A Belyaev, S S Biswal, B Bhattacharjee, G Bhattacharyya, L Calibbi, D Choudhury, E J Chun, D Das, A De Roeck, N G Deshpande, E Dudas, A Giri, D Grellshceid, R Godbole, S Goswami, M Guchait, M Hirsch, R Kaul, B Kodrani, M C Kumar, A Kundu, Y Mambrini, P Mathews, B Mellado, R Mohanta, S Mohanty, A Nyffeler, S Pakvasa, M K Parida, M Passera, C Petridou, S Poddar, P Poulose, A Rajaraman, G Rajasekaran, V Ravindran, Kumar Rao, D P Roy, Probir Roy, K A Saheb, V H Satheeshkumar, T Schwetz, A Tripathi, R Vaidya and S Vempati  相似文献   

5.
偏振能量色散X射线荧光光谱法在土壤环境监测中的应用   总被引:1,自引:0,他引:1  
以土壤和水系沉积物标准物质为校准样品,采用粉末样品压片制样.建立了偏振能量色散X射线荧光光谱仪测定土壤中As、Ba、Cu、Co、Cd、Cr、Mo、Mn、Ni、Pb、Sr、Ti、V、Zn、Rb、Sc、Bi、Si、Al、Fe、Ca、Mg、Na、K 24种元素的方法.该方法采用Al、CaF2、Fe、Zn、KBr、Al2O3、...  相似文献   

6.
We review the present status of the Lake Baikal neutrino experiment and present selected physics results obtained during the consecutive stages of the stepwise upgrade of the detector: from NT-36 to NT-96. The results cover atmospheric muons, neutrino events, neutrinos of very high energy, searches for neutrino events from WIMP annihilation, searches for magnetic monopoles, and environmental studies. We also describe an air Cherenkov array developed for studying the angular resolution of NT-200. From Yadernaya Fizika, Vol. 63, No. 6, 2000, pp. 1027–1036. Original English Text Copyright ? 2000 by Balkanov, Belolaptikov, Bezrukov, Budnev, Chensky, Danilchenko, Dzhilkibaev, Domogatsky, Doroshenko, Fialkovsky, Gaponenko, Garus, Gress, Kiss, Klimov, Klimushin, Koshechkin, Kuznetzov, Kulepov, Kuzmichev, Lovzov, Laudenskaite, Lubsandorzhiev, Milenin, Mirgazov, Moseiko, Netikov, Osipova, Panfilov, Parfenov, Pavlov, Pliskovsky, Pokhil, Popova, Rozanov, Sokalski, Spiering, Streicher, Tarashansky, Toht, Thon, Vasiliev, Wischnewski, Yashin. This article was submitted by the authors in English.  相似文献   

7.
Raman spectra of biological materials are very complex, because they consist of signals from all molecules present in cells. In order to obtain chemical information from these spectra, it is necessary to know the Raman patterns of the possible components of a cell. In this paper, we present a collection of Raman spectra of biomolecules that can serve as references for the interpretation of Raman spectra of biological materials. We included the most important components present in a cell: (1) DNA and RNA bases (adenine, cytosine, guanine, thymine and uracil), (2) amino acids (glycine, L ‐alanine, L ‐valine, L ‐serine, L ‐glutamic acid, L ‐arginine, L ‐phenylalanine, L ‐tyrosine, L ‐tryptophan, L ‐histidine, L ‐proline), (3) fatty acids and fats (lauric acid, myristic acid, palmitic acid, stearic acid, 12‐methyltetradecanoic acid, 13‐methylmyristic acid, 14‐methylpentadecanoic acid, 14‐methylhexadecanoic acid, 15‐methylpalmitic acid, oleic acid, vaccenic acid, glycerol, triolein, trilinolein, trilinolenin), (4) saccharides (β‐D ‐glucose, lactose, cellulose, D ‐(+)‐dextrose, D ‐(+)‐trehalose, amylose, amylopectine, D ‐(+)‐mannose, D ‐(+)‐fucose, D ‐(−)‐arabinose, D ‐(+)‐xylose, D ‐(−)‐fructose, D ‐(+)‐galactosamine, N‐acetyl‐D ‐glucosamine, chitin), (5) primary metabolites (citric acid, succinic acid, fumarate, malic acid, pyruvate, phosphoenolpyruvate, coenzyme A, acetyl coenzyme A, acetoacetate, D ‐fructose‐6‐phosphate) and (6) others (β‐carotene, ascorbic acid, riboflavin, glutathione). Examples of Raman spectra of bacteria and fungal spores are shown, together with band assignments to the reference products. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

8.
2DNMR在波谱学的化学应用中占据首要位置。本文简述了COSY,LRCOSY,COSYDEC,SECSY,DQC-COSY,RCT,INADIQUATE,RELAY,INVERSE,NOESY,HOESY,OHAHA,ROESY,HMQC,HMBC等谱的形状,指认步骤及其应用。  相似文献   

9.
The behavior of ternary and quaternary additions to NiTi shape memory alloys is investigated using a quantum approximate method for the energetics. Ternary additions X to NiTi and quaternary additions to Ni–Ti–Pd, Ni–Ti–Pt, and Ni–Ti–Hf alloys, for X=Au, Pt, Ir, Os, Re, W, Ta,Ag, Pd, Rh, Ru, Tc, Mo, Nb, Zr, Zn, Cu, Co, Fe, Mn, V, Sc, Si, Al and Mg are considered. Bulk properties such as lattice parameter, energy of formation, and bulk modulus of the B2 alloys are studied for variations due to the presence of one or two simultaneous additives.  相似文献   

10.
11种贝螺肉类27种微量元素的分析测试   总被引:12,自引:2,他引:10  
采用微波消解法处理贝肉类样品,并用ICP-AES法测定11种贝肉类中的27种微量元素Ca,Mg,K,Na,P,S,Zn,Mn,Fe,Cu,Cr,Co,Se,Sn,Ni,Al,Ti,V,Mo,Ba,Ge,Si,Cd,I,Pb,As和Hg,结果表明:ICP-AES法在测定多种微量元素的仪器方法中显示巨大的优势,11种贝肉类中含有20多种以上微量元素,淡水养殖的贝肉类比海水养殖的钙含量要高得多,有害金属元素主要存在着As和Pb的污染概率。  相似文献   

11.
We investigate the beam energy dependence of neutron and proton squeeze-out in collisions of197Au+197Au atE/A=400—800 MeV. The azimuthal anisotropy that describes the enhanced emission of mid-rapidity neutrons perpendicular to the reaction plane rises strongly with the transverse momentum of the neutrons. This dependence of the azimuthal anisotropy follows a universal curve — independent of beam energy — if the neutron momenta are measured in fractions of the projectile momentum per mass unit. Analogously, the kinetic energy spectra of mid-rapidity neutrons exhibit a universal behaviour as a function of the kinetic energy of the projectile. The members of the FOPI-collaboration: J.P. Alard, Z. Basrak, N. Bastid, I.M. Belayev, M. Bini, R. Bock, A. Buta, R. aplar, C. Cerruti, N. Cindro, J.P. Coffin, M. Crouau, P. Dupieux, J. Erö, Z.G. Fan, P. Fintz, Z. Fodor, R. Freifelder, L. Fraysse, S. Frolov, A. Gobbi, Y. Grigorian, G. Guillaume, N. Herrmann, K.D. Hildenbrand, S. Hölbling, O. Houari, S.C. Jeong, M. Jorio, F. Jundt, J. Kecskemeti, P. Koncz, Y. Korchagin, R. Kotte, M. Krämer, C. Kuhn, I. Legrand, A. Lebedev, C. Maguire, V. Manko, T. Matulewicz, G. Mgebrishvili, J. Mösner, D. Moisa, G. Montarou, P. Morel, W. Neubert, A. Olmi, G. Pasquali, D. Pelte, M. Petrovici, G. Poggi, F. Rami, W. Reisdorf, A. Sadchikov, D. Schüll, Z. Seres, B. Sikora, V. Simion, S. Smolyankin, U. Sodan, N. Taccetti, K. Teh, R. Tezkratt, M. Trzaska, M.A. Vasiliev, P. Wagner, J.P. Wessels, T. Wienold, Z. Wilhelmi, D. Wohlfarth, A.V. Zhilin.  相似文献   

12.
应用ICP-MS/ICP-AES测定榆钱中22种微量元素的含量   总被引:8,自引:3,他引:5  
榆钱是我国民间的一种优良野生食品资源。随着人们对食品安全意识的增强,其营养成分与有毒成分的含量逐渐受到人们的重视。借助ICP-MS/ICP-AES技术对野生榆树榆钱中的22种微量元素进行了研究。结果发现榆钱中含有丰富的人体所必需的元素,特别是Mg, Ca, Mn, Fe, Cu, Zn, Sr和Rb,分别达到224.57, 269.73, 9.23, 64.93, 1.68, 4.79, 7.68和2.21 μg·g-1(FW)(FW表示鲜重(下同));Li, B, V, Co, Ni, Se, Br, Mo和Sn,也分别达到318.43, 518.83, 265.52, 108.50, 411.21, 34.51, 51.72, 109.90和31.51 ng·g-1(FW)。除了有益元素以外,重金属元素Pb, Cd, As, Hg和Cr的含量也分别达557.87, 8.81, 345.55, 0.78和347.97 ng·g-1(FW),其含量偏高,虽然符合国家食品卫生标准,但是应当注意重金属含量的监测。  相似文献   

13.
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   

14.
In a population sample of residents of Novosibirsk between the ages of 45 and 69, the complex of the following chemical components of blood is determined by SR XRF: K, Ca, Fe, Cu, Zn, Ge, Se, Br, Rb, Sr, Zr, and Pb. Risk factors of chronic noncommunicable diseases are determined: obesity, arterial hypertension, dislipidemia, and their associations with chemical elements Ca, Cu, Rb, Y, and Pb.  相似文献   

15.
Summary We discuss the feasibility of a telescope consisting in a sampling array for extensive air showers measure combined with a muon tracking device. The sampling array will extend over a surface of ≥107 m2 while the muon tracking device will cover ≥104 m2. The telescope should be done with resistive plates counters and would become a very powerful device to study high-energy neutrinos and gamma-ray astronomy as well as cosmicray physics up to the highest energy (≥1019 eV) region. The content of this paper has been elaborated with the following people interested in performing the experiment: M. De Palma, G. Iaselli, C. Maggi, S. Natali, S. Nuzzo, A. Ranieri, C. Raso, F. Romano, F. Ruggeri, G. Selvaggi, P. Tempesta, G. Zito; A. Rossi, G. Susinno; A. Grillo, F. Ronga, V. Valente; P. Bernardini, P. Pistilli; A. Watson, R. Reid, M. Lawrence; M. Ambrosio, G. Barbarino, B. Bartoli, V. Silvestrini; R. Buccheri, M. Carollo, O. Catalano, J. Linsley, L. Scarsi; G. Bressi, A. Lanza, M. Cambiaghi, S. Ratti; M. Bonori, G. D'Agostini; M. De Vincenzi, E. Lamanna, P. Lipari, G. Martellotti, F. Massa, M. Mattioli, A. Nigro, S. Petrera; R. Cardarelli, F. Rossi, R. Santonico; L. De Cesare, G. Grella, M. Guida, F. Mancini, G. Marini, G. Romano, G. Vitiello; C. Cappa, B. D'Ettore Piazzoli, P. Ghia, G. Gomez, P. Trivero. [Bari, Cosenza, Laboratori Nazionali di Frascati Lecce, Leeds, Napoli, Palermo, Pavia, Roma I, Roma II, Salerno, Torino, Istituto di Cosmogeofisica del CNR].  相似文献   

16.
《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   

17.
ABSTRACT

A closed-vessel microwave-digestion method was developed for the determination of trace amounts of Be, V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Mo, Cd, Sb, Ba, Tl, and Pb by inductively coupled plasma mass spectrometry and Hg by cold-vapor atomic absorption spectrometry in cigarette tobacco samples. In order to gauge the effectiveness of the digestion procedure, recovery studies were conducted using solutions prepared from National Institute of Standards and Technology Standard Reference Material 1573a Trace Elements in Tomato Leaves and Polish Certified Reference Material Virginia Tobacco Leaves. Limits of detection were below 1 µg g?1 for all elements studied. Samples from two genuine-brand and three counterfeit packs were analyzed. The mean amounts of Be, As, Mo, Cd, Sb, Tl, Pb, and Hg were higher in counterfeit cigarettes, while the amounts of V, Cr, Mn, Co, Cu, Zn, Se, and Ba were comparable among legal and counterfeit cigarettes; the amount of Ni was higher in the legal cigarettes. Evaluation of Be, As, Mo, Cd, Sb, Tl, Pb, and Hg with their potential hazards for smokers is briefly discussed.  相似文献   

18.
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   

19.
Elemental analysis of fertilizer using laser induced breakdown spectroscopy   总被引:1,自引:0,他引:1  
In recent years, the use of fertilizers has increased to achieve high growth rate of agriculture products. With this increase the chemical impact of agricultural activities on the environment has also been enhanced. In order to keep the environment healthy, and clean, it is necessary to identify contaminants and characterize the sources of contamination. In this study, a comprehensive chemical characterization of a DAP fertilizer has been carried out using laser induced breakdown spectroscopy. Phosphorous, manganese, magnesium, iron, titanium, molybdenum, nickel, cobalt, aluminum, chromium, lead, and uranium traces are detected. Relative abundances of Phosphorous, manganese, magnesium, molybdenum, iron, titanium, nickel, vanadium, calcium, cobalt, cadmium, tin are 26.64, 17.75, 13 97, 8.25, 7.97, 7.11, 5.07, 3.15, 2.94, 1.94, 1,55, 1.73 percent, respectively, whereas relative abundances of sulfur, aluminum, chromium, lead, and uranium are less than 1% and their sum is 1.93% of the total sample.  相似文献   

20.
This report summarises the work done in the ‘Beyond the Standard Model’ working group of the Sixth Workshop on High Energy Physics Phenomenology (WHEPP-6) held at the Institute of Mathematical Sciences, Chennai, Jan 3–15, 2000. The participants in this working group were: R Adhikari, B Ananthanarayan, K P S Balaji, Gour Bhattacharya, Gautam Bhattacharyya, Chao-Hsi Chang (Zhang). D Choudhury, Amitava Datta, Anindya Datta, Asesh K Datta, A Dighe, N Gaur, D Ghosh, A Goyal, K Kar, S F King, Anirban Kundu, U Mahanta, R N Mohapatra, B Mukhopadhyaya, S Pakvasa, P N Pandita, M K Parida, P Poulose, G Raffelt, G Rajasekaran, S Rakshit, Asim K Ray, A Raychaudhuri, S Raychaudhuri, D P Roy, P Roy, S Roy, K Sridhar and S Vempati.  相似文献   

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