SIMS测定玻璃固化样品中铀分布的分析方法研究

玻璃固化是一种常用的高放废液固化方法,其优点在于具有较高的抗化学介质侵蚀的能力和很好的辐照稳定性、热稳定性和机械稳定性,其不足之处在于抗水浸出等性能有所下降而使其安全性需要进一步通过抗浸出实验来进行衡量和确认。使用二次离子质谱(SIMS)分析玻璃固化体中的放射性成分(如铀元素)的分布及浸出行为等各项指标,是一种评估玻璃固化体抗浸出性能的分析手段。本文应用SIMS测试模拟玻璃固化体,以碳作为镀膜材料通过真空蒸发镀碳的方法优化样品制备条件,有效地解决了样品导电性差的问题,~(235)U/~(238)U同位素测定结果约为7.9‰±0.395‰,基本符合制作模拟样品时所使用的天然铀的同位素特征(~(235)U/~(238)U参考值约7.3‰)。研究表明,建立的方法实现了铀元素同位素丰度的测量,能直接显示铀的分布情况,该方法可为研究玻璃固化体中放射性元素的浸出行为提供一定的技术支持。     

Drinking and irrigational feasibility of groundwater,GIS spatial mapping in upper Thirumanimuthar sub-basin,Cauvery River,Tamil Nadu

In the present study, the chemical characteristics of groundwater with respect to drinking and Irrigation water quality in upper Thirumanimuthar sub-basin, Cauvery River, have been studied. 51 groundwater samples were collected and analysed for pH, conductance, total dissolved solids, total hardness, calcium, magnesium, carbonate, bicarbonate, total alkalinity, chloride, sodium, potassium, sulphate etc. The values analyzed were evaluated in detail and compared with WHO water quality standards. It is observed that, for most of the groundwater quality parameters, the values are not potable for drinking and irrigational use. To understand the spatial distribution of unsuitable zones, ArcGIS was employed. Attributes were linked and spatial interpolation mapping was done. Inverse distance weighted interpolation technique was followed for raster and vector mapping. Finally the overlay analyses were also carried out to locate the worst quality zone.     

Electron-probe microanalysis of light elements in coal and other kerogen

Recent advances in electron microprobe technology including development of layered synthetic microstructures, more stable electronics and better matrix-correction programs facilitated routine microanalysis of the light elements in coal. Utilizing an appropriately equipped electron micro-probe with suitable standards, it is now possible to analyze directly the light elements (C, O and N, if abundant) in coal macerals and other kerogen. The analytical results are both accurate compared to ASTM methods and highly precise, and provide an opportunity to access the variation in coal chemistry at the micrometre scale. Our experiments show that analyses using a 10 kV accelerating voltage and 10 nA beam current yield the most reliable data and result in minimum sample damage and contamination. High sample counts were obtained for C, O and N using a bi-elemental nickel-carbon pseudo-crystal (2d = 9.5 nm) as an analyzing crystal.Vitrinite isolated from anthracite rank coal proves the best carbon standard and is more desirable than graphite which has higher porosity, whereas lower rank vitrinite is too heterogeneous to use routinely as a standard. Other standards utilized were magnesite for oxygen and BN for nitrogen. No significant carbon, oxygen or nitrogen X-ray peak shifts or peak-shape changes occur between standards and the kerogen analyzed. Counting rates for carbon and oxygen were found to be constant over a range of beam sizes and currents for counting times up to 160 s. Probe-determined carbon and oxygen contents agree closely with those reported from ASTM analyses. Nitrogen analyses compare poorly to ASTM values which probably is in response to overlap between the nitrogen K α peak with the carbon K-adsorption edge and the overall low nitrogen content of most of our samples.Our results show that the electron microprobe technique provides accurate compositional data for both minor and major elements in coal without the necessity and inherent problems associated with mechanically isolating macerals. Studies to date have demonstrated the level of compositional variability within and between macerals in suites of Canadian coals.     

Report (1967–1981) on Four ANRT Rock Reference Samples: Diorite DR-N, Serpentine UB-N, Bauxite BX-N and Disthene DT-N

All data reported by 200 analysts (106 laboratories) are presented for the four ANRT samples: Diorite DR-N, Serpentine UB-N, Bauxite BX-N and Disthène DT-N. Recommended values are given for the major and minor elements. As far as the as trace elements are concerned, DR-N has been characterized for 35 elements whereas the other three samples have been for only 20 elements. Wherever possible, brief comments have been inserted so as to explain our way of assigning recommended or proposed values.
After more than a decade of existence the total number of data reported for all the four samples reach only 3200 units which are not sufficient enough for a valid evaluation of compiled data. It is also pointed out that these samples are most likely to be available even during the next century as they have been prepared in large quantities of the order of one ton. A plea is therefore made for contribution of more data particularly for trace elements and for major elements which are present as trace elements in UB-N, BX-N and DT-N.     

Effects of heavy metals on some soil biological parameters

The soils most polluted by heavy metals are probably alluvial soils. One of them is the alluvium of the Litavka River. The heavy metal content was much higher in some cases than the threshold values, allowed by the Czech standards. The effect of soil contamination on enzyme activity is presented. Generally, the values of enzymatic activities were highest in the soil above the source of contamination and they decrease as they approach the source of contamination. All measured parameters were affected by heavy metal concentrations. Our results demonstrate that several parameters of microbial activity could be used as good indicators of increasing concentrations of Cd, Pb and Zn in soil.     

Evaluation of groundwater quality in the Cihanbeyli basin, Konya, Central Anatolia, Turkey

The Cihanbeyli basin is located in the northern part of Konya in the Central Anatolian region, Turkey and is characterized by semi-arid climatic conditions and scarcity in water resources. The suitability of groundwater quality for drinking and agricultural purposes in the Cihanbeyli basin was assessed by measuring physicochemical parameters, including major cation and anion compositions, pH, total dissolved solid, electrical conductivity, and total hardness. For this purpose, 54 samples were collected from different sources viz. deep wells, shallow wells, and springs. Results from hydrochemical analyses reveal that groundwater is mostly affected by salty and gypsiferous lithologies. Evaporite minerals such as gypsum, anhydrite, and chloride salts make high contributions from the recharge areas (west, northwest, and southwest parts) toward the discharge area (central and eastern parts). High values of total dissolved solids in groundwater are associated with high concentrations of all major ions. A comparison of groundwater quality in relation to drinking water standards showed that most of the water samples are not suitable for drinking. Based on sodium absorption ratio values and percent sodium, salinity appears to be responsible for the poor groundwater quality, rendering most of the samples unsuitable for irrigation usage. It is concluded that evaporation and mineral dissolution are the main processes that determine major ion compositions.     

A comparison of liquid limit values for fine soils: A case study at the north Cairo-Suez district,Egypt

This study compare liquid limit values obtained by the Casagrande apparatus, Russian and British drop cone penetrometer. Liquid limit determined for clay samples collected from 10 boreholes at the Cairo-Suez district (north western part of Badr City), Egypt. It is the most important geotechnical parameter used of fine-grained soils. The liquid limits for 40 natural clay samples varying between 27.8 and 69.7%. It is found that the liquid limit determined by the Casagrande apparatus and Russian standard (cone penetrometer) give essentially the same results with a difference of < 5%. It is observed that the values of Casagrande apparatus were generally lower than those obtained by the cone penetrometer with Russian standard. In addition, Casagrande apparatus for some samples, which had liquid limits of more than 60%, give a higher result. The liquid limits determined by the Russian and British standards are not consistent with a difference of < 1%. Besides, the results which determined by the Casagrande apparatus and British standards (BS), provide equivalent values with a difference of < 3%.     

Concentrations of B,Sm, Gd and H in 24 Reference Materials*

Analysis of 24 reference materials for B, Sm, Gd, H, has been carried out over several years, using prompt gamma neutron activation analysis. The results are compared with values obtained by other workers, in order to better calibrate these standards. In most cases our results of repeated analysis of RMs show agreement with results from other laboratories, using various methods. A djustments to working values are proposed in some cases.     

Physico-chemical analysis of surface and groundwater around Singrauli Coal Field, District Singrauli, Madhya Pradesh, India

The present study was carried out in Singrauli area of the north India to know the water quality at selected sites. Physico-chemical parameters like pH, total dissolved solids (TDS), bicarbonate, hardness, calcium, magnesium, sodium, potassium, chloride, sulfate, copper, iron, cobalt, manganese, zinc, and chromium were analyzed in 27 water samples. Locations selected for sampling were based on the preliminary field survey carried out to understand the overall impact of mining and industrialization on the surface and groundwater resources of Singrauli. Base map, drainage map, and land use/land cover of the study area were prepared from Survey of India topographic map 63 L/12 on 1:50000 scale and satellite data of IRS P6 LISS III 4th May 2010. Land use were categorized into 15 categories out of which major area occupied by open forest covers 20.33 %, uncultivated land 20.25 %, cultivated land 12.60 %, dense forest 11.00 %, and other categories cover 35.82 %. The results obtained are compared with World Health Organisation standards for drinking water quality. The physico chemical analysis shows alkaline nature of water, soft to moderately soft, TDS and total alkalinity exceeds the desirable limit. The major ions in water like calcium, and magnesium are within desirable limits, and sulfate and potassium exceed in limit at some locations, whereas sodium and chloride show higher values. The minor ions like copper and zinc show values within desirable limits whereas iron, cobalt, and chromium show higher values than the desirable limits which deteriorate the quality of water.     

狭缝系统与伊利石结晶度Kuebler指数的测定及相关问题讨论

根据实验结果,衍射峰半高宽随接收狭缝增大而呈二次工线线性增大。扫描速度与扫描步长的确定应遵守Ｗａｎｇ（１９９４）提出的关系式,并确定在相对误差小于〈５％的范围内。固定样品条件,选定最优实验条件下使用国际标样标定系统偏差是伊利石结晶测量中必不可少的重要步骤。不固定样品条件和实验条件,同一样品的伊利石工值将因条件的变化而不同;固定样品和实验条件而不使用国际标样标定系统偏差,则无法与他人数据进行对比,其     

A study on hydrochemical elucidation of coastal groundwater in and around Kalpakkam region, Southern India

The chemical composition of 29 bore well water samples throughout the Kalpakkam region, South India, was determined to identify the major hydrogeochemical processes and the suitability of groundwater for domestic and irrigation purposes. The hydrochemical data were analyzed with reference to World Health Organization (WHO) standards and their hydrochemical facies were determined. The Piper plot shows that most of the groundwater samples fall in the field of mixed calcium–sodium–bicarbonate type followed by sodium–chloride, calcium–bicarbonate and mixed calcium–magnesium–chloride water types. The concentration of total dissolved solids exceeds the desirable limit in about 14% of samples; alkalinity values exceed the desirable limit in about 34% of the samples. The concentration of sulphate is well within the desirable limit at all the locations. The dominance of various heavy metals in the groundwater followed the sequence: Zn > Fe > Mn > Cu > Ni > Pb > Cr > Cd. Among the metal ions, the concentration of chromium and cadmium are within the permissible limit. Data are plotted on the US Salinity Laboratory diagram, which illustrates that most of the samples fall in the field of high salinity and low sodium hazard, which can be used to irrigate salt tolerant and semi-tolerant crops under favorable drainage conditions. Based on the analytical results, chemical indices like sodium adsorption ratio and residual sodium carbonate were calculated which show that most of the samples are good for irrigation.     

Research on quality changes and influencing factors of groundwater in the Guanzhong Basin

This paper studies the distribution features, the chemical elements beyond standards and the influencing factors of shallow groundwater quality in the Guanzhong Basin through the data monitored in the last twenty years. The final purpose is to comprehensively evaluate the divisions of groundwater quality in the Guanzhong Basin. Results show that , the groundwater quality is in good shape, and suitable for drinking. Drinking accounts for 16.02% of the total, most of which are distributed in the lubotan of Weibei. Some come from loess plateau of Qian-Liquan County and some are generated by the industrial pollution of Xingping City. Materials exceeding standards include chloride, sulfate, three nitrogen, fluoride, manganese, iron, hexavalent chromium and so on. The main factors influencing the quality of shallow groundwater include groundwater exploitation, natural background value of special components and precipitation, among which the groundwater exploitation poses the greatest impact. The depth of water is positively correlated with the concentration of sulfate, nitrate and total hardness.     

激光剥蚀-电感耦合等离子体质谱准确测定锆石中钛的含量

外标物质及内标元素的选择是激光剥蚀-电感耦合等离子体质谱(LA-ICP-MS)准确测定元素含量的关键因素之一。文章选用玻璃标准参考物质NIST 610、GSE-1G、BHVO-2G、BCR-2G、ATHO-G、KL2-G和T1-G作为外标,Si或Zr作为内标,对锆石M257中的Ti进行LA-ICP-MS微区原位测定。结果显示,选择Si或Zr作内标,采用BCR-2G、ATHO-G、KL2-G和T1-G作外标时,Ti含量测定值与参考值之间差异均较大,因此它们不适合作外标物质。采用BHVO-2G作外标和Si作内标,NIST 610作外标和Zr作内标,Ti含量测定值与参考值之间的差异均小于4%,因此BHVO-2G和NIST 610可有条件地作为外标物质。选择Si还是Zr作内标,GSE-1G作外标时,Ti含量的测定值与参考值之间的差异均小于3%,说明GSE-1G是较为合适的外标物质。选用GSE-1G作为外标,Si作内标,对5个标准锆石中的Ti含量进行了测定,结果显示,Ti元素在锆石91500中分布不均匀,而在锆石GJ-1、M257、PENGLAI和MUDTANK中分布均匀。在Ti元素分布均匀的GJ-1、M257、PENGLAI和MUDTANK等4个锆石中,由于Ti的含量均小于5μg/g,不适合作为锆石中Ti元素测定用的外标物质,但可作为测定时的质量监控样品。     

Instrumental Neutron Activation Analysis of Twenty-Nine International Geochemical Reference Samples

Results of measurements of twenty-seven elements, most of them in trace amounts, by Instrumental Neutron Activation Analysis (INAA) in twenty-nine international geochemical reference samples from Canada, U.S.A., Japan, France and South Africa, are reported and compared with available literature values. In general, our data agree well with literature values. The disagreement of our results (e.g., Zr in Canadian syenites and several trace elements in USGS ultrabasic rocks) with those reported by other workers is briefly discussed and ways of improving INAA are pointed out. The present report includes data on several trace elements for which existing data are rather scarce.     

长江三角洲沉积物标准物质研制

美国、加拿大等国家先后研制了10余个海湾和河口沉积物标准物质,但定值成分较少,大多侧重于有机污染物和放射性核素值。我国于2007年研制了3个黄河三角洲沉积物标准物质,为进一步满足近海地球化学调查及资源勘探的需要,本文按照ISO导则35和国家一级标准物质技术规范,研制了2个长江三角洲沉积物标准物质。按照不同粒径采集两个候选物样品,样品经干燥、球磨至200目,采用电感耦合等离子体质谱和发射光谱法进行均匀性检验,结果表明F实测值小于列表临界值F0.05(24,25)=1.96,样品均匀性良好。在两年时间内采用X射线荧光光谱法进行了4次稳定性检验,未发现统计学意义上的明显变化,样品稳定性良好。由12家有技术权威的实验室共采用13种准确、可靠的分析方法进行协作定值,最终定值元素53项,涵盖了主量、微量及全部稀土元素,其中主量成分含量呈梯度分布,如Al2O3的含量分别为16.42%、11.48%。该系列标准物质定值元素种类多,定值方法准确,能够为河口三角洲地区地质及环境调查的分析测试工作提供可靠的质量保证。     

Geochemical characterization of groundwater from northeastern part of Nagpur urban,Central India

Hydrogeochemical investigations are carried out in the northeastern part of Nagpur urban to assess the quality of groundwater for its suitability for drinking and irrigation purposes. Groundwater samples are collected from both shallow and deep aquifers to monitor the hydrochemistry of various ions. The groundwater quality of the area is adversely affected by urbanization as indicated by distribution of EC and nitrate. In the groundwater of study area, Ca²⁺ is the most dominant cation and Cl⁻ and HCO₃ ⁻ are the dominant anions. Majority of the samples have total dissolved solids values above desirable limit and most of them belong to very hard type. As compared to deep aquifers, shallow aquifer groundwaters are more polluted and have high concentration of NO₃ ⁻. The analytical results reveal that most of the samples containing high nitrate also have high chloride. Major hydrochemical facies were identified using Piper trilinear diagram. Alkaline earth exceeds alkalis and weak acids exceed strong acids. Shoeller index values reveal that base-exchange reaction exists all over the area. Based on US salinity diagram most of samples belong to high salinity-low sodium type. A comparison of groundwater quality in relation to drinking water standards showed that most of the water samples are not suitable for drinking purpose.     

Hydrogeochemical parameters for assessment of groundwater quality in a river sub-basin

Hydrogeochemical studies were carried out in the Ghataprabha River sub-basin to assess the quality and suitability of groundwater for domestic and irrigation purposes. In the present study, an integrated, geophysical and chemical investigation was carried out in the basaltic terrain. Groundwater samples were collected covering the entire major hydrogeological environment for one hydrological cycle. Comparison of the groundwater quality in relation to drinking water quality standards proves that most of the water samples are not suitable for drinking. Chemical indices such as sodium percentage, sodium adsorption ratio and chloroalkaline indices used for evaluating the water quality for irrigation suggest that the majority of the groundwater samples were good for irrigation. Positive values of 74% of groundwater samples indicated the absence of base exchange reaction (chloroalkaline disequilibrium) and negative ratio of 26% samples indicated a base exchange reaction (chloroalkaline equilibrium). Resistivity tomography studies revealed that the high concentration of total dissolved solids, chloride and sodium were due to the local anthropogenic activities and weathering of basalt rocks.     

The occurrence of potentially hazardous trace elements in five Highveld coals, South Africa

Permian coals of the southern hemisphere are generally considered to contain lower concentrations of sulfides, halogens, and trace elements when compared to northern hemisphere Carboniferous coals. Few studies have considered the trace element content in South African coals, and little or no work has been published for Highveld coals. Of the nineteen coal fields in South Africa, the Highveld coal field is one of the nine currently producing, and is second largest in terms of production. Five run of mine samples and a high ash middlings product from the Number 4 Lower seam were analyzed, totaling six sample sets. Fourteen trace elements (As, Cd, Co, Cr, Cu, Hg, Mn, Mo, Ni, Pb, Sb, Se, V, and Zn) were selected for this study based on the global perception that these elements may be hazardous to human health and/or the environment when they are released during coal utilization. Several sample preparation techniques were tested using certified reference materials (SARMs 18, 19 and 20) to determine the most repeatable technique for these coals. The samples were analyzed by ICP-AES and CVAA (Hg only). Microwave digestion proved to be generally unreliable despite the utilization of several different methods. A slurry direct injection method into the ICP-AES provided good correlations with the reference material, but requires further development to enhance the confidence level in this relatively unexplored technique. Samples prepared based on three ASTM standards for the determination of trace elements in coal provided repeatable results in most instances, and were the preparation methods utilized for the Highveld coals.The trace element values determined for the Highveld coals are generally in good agreement with values available in literature for South African coals, with the exception of Hg, Mn and Cr. Hg values reported here are lower, Cr and Mn higher. Results generally agree well with analyses on the same samples conducted by the United States Geological Survey. When considering the global ranges for trace elements, the Highveld range values are within Swaine's range boundaries with the exception of Cr. Compared to the cited global average values for the fourteen trace elements determined, the values obtained for the Highveld coals generally fall below or well below these average values, with the exception of Cr and Mn. Concentrations of Cd and Cu are lower compared to global average values, and As, Mo, Pb, Se, Sb, and Zn can be considered low to very low. Arsenic is ten times lower compared to typical USA values. Concentrations of Co and Ni are similar to global averages, with V and Hg being very slightly higher. The middlings samples reported higher concentrations of most elements, related to the higher ash content of these samples. Of interest, the chalcophile elements determined are all depleted in the Highveld coals compared to global averages, and the siderophile elements are enriched or comparable to global averages.Risk-based health studies in the USA on coals with similar or higher Hg and significantly higher As contents have not reported negative health effects, and therefore it could be assumed that the mobilization of these trace elements from the five Highveld coals are unlikely to cause human health problems. Work is ongoing to determine the modes of occurrence of these HAPs and to address the partitioning behaviors and speciation states of these elements during coal utilization.     

Fractional Determination of Gold in Twenty Six Geological Reference Materials by Sequential Extraction with Graphite Furnace Atomic Absorption Spectrometry

A method is described to estimate the chemical form of gold (Au) in a variety of geological reference samples, combining a sequential extraction scheme with graphite furnace atomic absorption spectrometry, after extraction of Au as iodide or chloride with methyl isobutyl ketone. The fractions dissolved by sequential extraction are empirically defined as the exchangeable, amorphous, metallic, aqua regia-soluble and residual fractions. The amounts of Au in the amorphous fraction have been derived mainly from oxide or amorphous phases, and the chemical forms of Au are considered to be mostly amorphous and partly metallic. The metallic fraction of Au is likely to exist as submicroscopic grains of native metal which are relatively free from the rock-forming minerals, whereas the aqua regia-soluble or residual fraction of Au may be bound more intimately perhaps as inclusions or solid solutions of either native metal or electrum in most cases. Satisfactory agreement was observed between the sum of the Au values from exchangeable to residual fractions and the reported total Au values, except for a few samples which contained a large amount of reducing materials. Analytical results of Au for twenty six geological reference materials are tabulated, and geochemical and mineralogical features are discussed.     

新一代高精度高灵敏度的表面热电离质谱仪(Triton TI)的Nd同位素测定

利用在南京大学成矿作用研究国家重点实验室建立的新一代高精度高灵敏度的表面热电离质谱仪 (TritonTI) ,可以实现比以往更高精度的Nd同位素测定。 3个国际溶液标样的反复测定结果NdLaJolla :14 3 Nd/ 14 4 Nd为 0 .5 1184 2± 4 ;NdJN di 1:14 3 Nd/ 14 4 Nd为 0 .5 12 10 4± 6 ;NdJMC :14 3 Nd/ 14 4 Nd为 0 .5 115 87± 10。 1个国际岩石标样的测试结果BCR 2 :14 3 Nd/ 14 4 Nd为 0 5 12 6 2 4± 3。上述测试结果与国际上很多实验室的测试结果一致 ,但测试精度优于以往。综合分析表明 ,利用这一最新型号的表面热电离质谱仪 (TritonTI) ,可以实现高精度的Nd同位素组成测试 ,测试精度一般优于 5× 10 -6。