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月球的起源是月球研究的核心问题。月球探测任务返回的数据和样品极大地提高了人类对地月系统的认知,同时也发现了更多未解之谜,亟待未来的探测任务和科学研究来解答。嫦娥五号月壤是我国首次地外天体采集返回的样品,也是继美国和苏联探月采样任务45年后人类再次获得的月球样品。鉴于月球样品的珍贵性和特殊性,利用先进技术开展其全元素含量的非破坏精准分析对于认识月球演化和月球资源就地开发利用具有重要的意义。依托大型核反应研究堆和加速器中子注量率优势,利用中子活化分析技术可实现月球样品中的全元素非破坏分析:1)仪器中子活化分析技术(INAA)可测量Na—U元素之间的60余种元素;2)瞬发γ中子活化分析技术(PGNAA)可补充测量INAA不适合测量的元素如H、B、C、N等;3)中子深度剖面分析技术(NDP)可测量样品近表面(微米级)聚变能源3He的浓度深度分布;4)缓发中子测量技术(DNC)可定量样品中痕量裂变核素如235U和239Pu,并结合INAA可测量238U/235U同位素比值;5)14 Me... 相似文献
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等离子体质谱法测定地质样品中痕量稀土元素的基体效应 … 总被引:2,自引:0,他引:2
采用模拟地质样品中稀土元素间天然组成比的基体匹配校正标准溶液进行外标校正,有效地抑制了地质样品分析中的基体效应,以^115In-^103Rh双内标元素校正,监控和校正分析信号的短期和长期漂移;通过单个稀土元素及钡的氧化物,氢氧化物的测定计算出等效的干扰浓度,进而校正了稀土元素分析中多原子离子干扰。建立了地质样吕吕痕量稀土元素测定中基体效应及多原子离子干扰的校正方法。通过对5个标准参考物质的分析,定 相似文献
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中子活化法研究稀土矿区植物体中稀土元素的分布特征 总被引:25,自引:3,他引:25
用仪器中子活化法测定了我国江西赣南某离子吸附型稀土矿区生长的17种不同植物中8个稀土元素的含 研究了稀土元素在植物体内的分布特征。结果表明,称土矿区植物体内的稀土元素含量较高,其中铁芒萁叶中部属然土含一可达3000μg/g以上,比其它植物叶高2-3个数量级。植物体各部位的稀土含量分布一般为根〉叶〉茎。经球粒陨石归一化后,稀土元素分布模式均与其母土基本相似。然而,在植物从土壤吸收及输送的吕,稀土元素 相似文献
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用激光激发原子荧光光谱仪测定南极冰雪样品中铅含量 总被引:3,自引:0,他引:3
自行研制的原子荧光光谱仪,由于无焰石墨炉原子化器,准分子激光器泵浦的脉冲染料激光器等组成。用其对95个南极冰雪样品中的铅进行了测量,其含量在4×10^-12-4.7×10^-11g/mL之间。本方法的检出限为0.2×10^-12g/mL,精密度为7%。. 相似文献
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本文全面阐述了南极冰雪样品中重金属分析测定的发展概况和极地样品分析中出现的困难,评述了各种分析方法(包括富集技术、超灵敏的分析技术)的优缺点,并指出其发展方向。引用文献47篇。 相似文献
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磁州窑古瓷中微量元素的中子活化分析 总被引:2,自引:0,他引:2
系统地研究我国古代名窑瓷器中微量元素的含量,整理出这些元素含量变化的规律,并通过这些规律来寻找器物的地方特征和时代特征是我们整个研究计划的目的。本文是整个计划的第三篇,分析的对象是我国宋代名窑之一的磁州窑的产品。磁州窑位于河北省彭城及其以西的漳河上游,集中于观台镇、东艾口村以及冶子村一带,宋代窑址居多,是当时我国北方的著名民窑之一。磁州窑产品硕实浑厚,色彩鲜明简洁,花纹线条明快,具有典型的北方民族特点。釉色以白、褐和黑三种为主,器形也多是碗、盆、罐、盘等日常家用食器和容器。花纹以釉绘、剔花、划花、刻花等技法表现出来的花卉、水草、鱼虫、鸟兽等居多,充分反映了宋代民间艺术朴实淳厚的风格。为了实现我们的目的,试样都是在废弃的窑址上收集的,经过整理,选取其中具有代表性的典型器物,经过反应堆中子活化后,分析测定其中所含微量元素的含量,为磁州窑研究提供实验数据。 相似文献
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《Analytical letters》2012,45(14):1233-1248
Abstract An instrumental neutron activation analysis with Ge(Li) γ -spectrometry and computer-assisted data reduction, has been developed for the determination of more than 20 elements in different liquid fuels. Organo-metallic standard solutions were mixed to obtain suitable standards. Two neutron irradiations and 4 γ-spectrometric measurements are required for each sample. Corrections were taken into account for a few spectrometric and nuclear interferences. The overall standard deviation for nearly all elements is mainly determined by counting statistics. The following elements can be determined : Na, Al, S, Cl, K, Sc, V, Cr, Fe, Co, Ni, Cu, Zn, As, Se, Br and La whereas the concentration of the following elements are mostly near the limit of detection: Mg, Mo, Sb, Ba, Th and Hg. 相似文献
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M. Kawano J. Falandysz T. Wakimoto 《Journal of Radioanalytical and Nuclear Chemistry》2003,255(2):235-237
Instrumental neutron activation analysis was performed to measure the levels of extractable organohalogens (EOX) in the organisms from the Antarctic marine ecosystem. The results show that EOX (EOCl, EOBr and EOI) were found in all the samples analyzed. The highest concentration was determined in the ascidian sample. The concentration order of EOX was mainly EOCl>EOBr>EOI with the exception of nemertine, ascidian, fish and adelie penguin samples. The concentrations of man-made organochlorines (DDTs and CHLs) were analyzed by GC-MS, and the results were compared with the concentrations of EOX determined in the same samples. The results show that the contribution of known man-made organochlorines in EOCl was less than 3%. This means that a large amount of unknown organochlorine compounds is present in Antarctic marine organisms. 相似文献
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A procedure has been developed for the determination by thermal neutron activation analysis of trace amounts of total chlorine in the Electro-Hydraulic-Control /EHC/ fluid used by the Hadera Power Station in various hydraulic systems. Irradiation for 1 min near the core of a nuclear reactor is followed by high resolution gamma-ray spectrometry using a Ge/Li/ detector. Chlorine amount is quantitatively determined by measuring the gamma-ray photopeaks of the radioactive nuclide38Cl. The system response is linear in the concentration ranges investigated. Chlorine concentration in a fresh hydraulic fluid sample was found to be 17.6±0.5 ppm. The limit of detection, when assaying a 1 cm3 sample of fluid under the present experimental conditions, is 1 g of chlorine and the corresponding concentration is 1 ppm. 相似文献
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T. Balaji R. N. Acharya A. G. C. Nair A. V. R. Reddy K. S. Rao G. R. K. Naidu S. B. Manohar 《Journal of Radioanalytical and Nuclear Chemistry》2000,243(3):783-788
Elemental concentrations of a few medicinal leaves are determined by instrumental neutron activation analysis using the single comparator (k
0) method. Data obtained for neem leaves, collected from two different places, have been used to see the effect of soil condition. The applicability of the method particularly for the simultaneous determination of Ca, Mg, V and Al in biological matrices has been evaluated in terms of the detection limit, precision and accuracy. The method was validated by analysing the NIST Standard Reference Material (SRM-1571) and it was found that the elemental concentrations measured in SRM-1571 are within ±10% of the reported values. 相似文献
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《Analytical letters》2012,45(7):445-450
Abstract Tellurium has been determined at milligram and submilligram levels in the presence of uranium by a strictly instrumental photon activation 121 analysis procedure. The 575 keV gamma ray of Te was measured. At a decay time of three weeks, this gamma ray peak was interference-free. As little as 0.4 mg of tellurium was determined and the method evidences that sensitivity would increase with irradiation time. 相似文献
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Instrumental Neutron Activation Analysis (INAA) is employed for its important analytical properties. Fundamentally, INAA is a multi-elemental technique allowing the determination of about 40 elements with a good Limit of Detection. In this paper we applied this nuclear technique to study the element composition in PM10 determining about 30 elements.25 filters were collected in downtown Rome from October 1999 to April 2000 and irradiated at the nuclear reactor Triga Mark II (ENEA-Casaccia Laboratories). The γ-ray measurements have allowed the quali- and quantitative analysis. The element levels in PM10 with the relative correlations have been determined: basically, the concentrations are very low.Furthermore, the enrichment factors of all elements will be reported in order to understand the natural or anthropogenic origins of the particulate matter: some elements may be attributed to long-range transport phenomena from other natural and/or anthropogenic sources. 相似文献
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采用仪器中子活化法(INAA)测定了金属钛中锰、砷、锑、钽、钨等5种痕量杂质元素含量,分析中采用GEM 70P高纯锗γ谱仪及grammavision 32分析软件。经预处理的样品割成5mm×5mm×1mm大小的薄片,其质量约180mg,与标准一起置于反应堆中照射,中子通量为1.0×10~(13)cm~(-2)·s~(-1)。上述5种元素的探测下限依次为0.022,0.049,0.032,0.097,0.015μg。将方法用于分析水沉积物标准物质(GBW 07312),锰、钽、锑及钨4种元素的测定值与证书值相符。 相似文献
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The simultaneous determination of heavy metals by instrumental neutron activation analysis (INAA) in some environmental samples have been considered. A new approach has been proposed to assess the potentialities and the most adequate use of INAA for each particular heavy metal. 相似文献
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The advantages of relative analytical methods over absolute methods for calculating element concentrations have been demonstrated. A procedure for the neutron activation analysis of samples of unknown composition was proposed based on the numerical simulation of the gamma spectra of test samples. 相似文献