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1.
Selenium was determined in duplicate portions from three bottles of six U.S.G.S. standard rocks by a spect rofluorimetric procedure. The following averages, as p.p.m. Se, were obtained: PCC-1, 0.031; GSP-1, 0.088; BCR-1, 0.12; SCo-1, 0.91; MAG-1, 1.3; and SGR-1, 3.7. One-way analysis of variance of the several sets of data showed no significant differences in the selenium content among bottles of any specific rock; these samples may be accepted as homogeneous for their selenium contents by this analytical method.  相似文献   

2.
Spectrographic determinations for twenty trace elements in the six new U.S.G.S. silicate rock standards along with the rock standards G-1, W-1, SR-1, GR and BR are given. Most of the results represent the average of triplicate determinations on each of five splits of the portions of the standards available to the authors. Thus, the preferred values represent, in most cases, the average of fifteen replicate determinations.  相似文献   

3.
汞污染土壤的萃取修复技术研究   总被引:1,自引:0,他引:1       下载免费PDF全文
陈宗英  张焕祯 《地学前缘》2012,19(6):230-235
分别采用HAc、NH4Ac、KI、EDTA、Na2S2O3等萃取剂萃取污染土壤中汞,研究了萃取剂对汞的萃取效果和萃取条件对萃取率的影响,并分析了用Na2S2O3溶液萃取前后土壤中汞的形态变化。结果表明,Na2S2O3水溶液对汞的萃取效果最好,适宜萃取条件为:浓度0.1 mol·L-1、土液比1∶6、萃取时间12 h,当土壤中汞浓度为107.86 mg/kg时,萃取率为65.32%。污染土样在适宜萃取条件下经Na2S2O3溶液萃取后,土壤中可交换态汞、酸溶态汞和硝酸溶态汞基本完全去除,土壤中汞的生物有效性显著降低;萃取后土样的浸出毒性检测符合《危险废物鉴别标准 浸出毒性鉴别》(GB 5085.3-2007)中要求的无害化堆放标准。  相似文献   

4.
Determinations of trace amounts (with one exception) of chloride are reported for 41 international geochemical reference standards, 12 of which have no previously reported literature values. All determinations were made by the chloride-specific ion-selective electrode method of Aruscavage and Campbell with certain refinements. Chlorine is separated from most other elements in geologic materials by acid-dissolution in a gas diffusion cell, and is subsequently determined as the chloride ion in basic solution. A statistical F-test was applied to 19 of the standards for which three bottles of each were analyzed in triplicate with no failures. All these standards, plus the other 22 for which six analyses were performed on a single bottle, exhibited a relative standard deviation of 1-6% for concentrations of chloride >50 ppm. For most samples chloride values agree well both with available, reported experimental values and with recommended or consensus values.  相似文献   

5.
The mercury contents of 109 reference samples of 12 organizations have been determined by flameless atomic absorption spectrometry. The homogeneity of mercury in the six USGS samples issued in 1964 was tested twice, a year apart, using unopened bottles of samples. The analysis of variance of these data in the form of a design with a single variable of classification showed that the mercury contents of the 12 sets can be considered homogeneous at F 0.95 and that 10 of these sets can be considered homogeneous at F 0.90 , a more stringent test.
Data for other reference samples were generally obtained using Youden Squares. This experimental design was used so that we could determine the significance of the variation attributable to some cause on the days on which mercury was determined, to the order in which the determinations were made on the several days, and to the mercury contents of the samples in each design. For the latter, one may assume that the mercury contents of samples will differ and that a significant F ratio may be obtained. For the principal variable of classification, the variation attributable to some cause on the days on which mercury was determined was significant for only 1 of 9 analyses of variance of sets of data but we have not been able to explain the cause of the significance.
The mercury contents of the several types of samples, except for micas, dunites, and perhaps the granodiorites, depend on the origin of the samples. The mercury contents of ande-sites and basalts of continental origin are higher than those for similar samples originating in island arcs or the circum-Pacific belt. We conclude that the high and extremely variable mercury content of W-1 is probably due to mercury resulting from the use of mercury fulminate detonators in the quarry prior to the collection of the sample.  相似文献   

6.
张耀奎  肖海斌 《四川地质学报》2012,32(3):356-357,366
为了寻找一种灵敏准确测定有机污染物水样中微量汞的方法,通过高锰酸钾—过硫酸钾消化氢化物发生原子荧光光谱法测定,发现汞含量在0.100 0~1.000 0ug/L范围内呈线形关系,相关系数为0.999 6,检出线为0.006 6ug/L,相对标准偏差在0.7% ~ 2.3%,样品加标回收率在93.1%~102.9%之间.该方法检出线低,灵敏度高,精密度好,准确度好,适合于有机物较多体系水样中汞的测定.  相似文献   

7.
Based on the most recent compilation of analytical data, a new set of “usable values” is calculated for six of the best known silicate rock reference samples produced by the U.S. Geological Survey. The latest version of the “best laboratories” method is described and results are compared with other recently published values.  相似文献   

8.
Ten U.S. Geological Survey rock standards have been analyzed for trace elements by instrumental neutron activation using a low flux reactor and Ge detectors. Results compare favorably with the current working values for all elements except Mo. REE values that have been determined are generally slightly lower than accepted values. Data obtained for rocks that have very low trace element concentrations (e.g., BIR-1) will aid in refining the working values for these standards.  相似文献   

9.
Additional data for gabbro, GOG-1, were determined by instrumental-neutron-activation analysis, atomic-absorption spectrometry, and semi-quantitative spectrographic analysis. F ratios calculated in the analysis of variance for 26 sets of data for elements determined by the three methods were not significant, and hence the elements are distributed homogeneously among the bottles. The agreement between our data and the averages previously published ranges from very good to poor. More analytical data are necessary to establish reliable estimates of the concentrations of elements in GOG-1 and in two other gabbros so that three gabbros may be available to geochemists for use as standards.  相似文献   

10.
Forty-four components in six bottles of BHVO-1 have been determined using wet chemical, atomic absorption, X-ray fluorescence, ion sensitive electrodes, and neutron activation techniques. No indications for systematic inhomogeneity were found, but the average ferrous iron contents of two bottles are lower than the averages of the other four.  相似文献   

11.
Breakage-induced shell repair and drilling were studied in 548 shells belonging to 24 species of gastropod from the Ripley Formation (latest Campanian-Maastrichtian) of the south-eastern U.S.A. Frequencies of repair are high even by Recent standards. These is no relationship between the frequency of shell repair and shell architecture. Repair increases in frequency with increasing shell length. Drilling, which is less common in Ripley gastropods than in most warm-water Tertiary species, decreases in frequency with increasing shell length.  相似文献   

12.
The recent experience of the rising cost of exploiting new material resources in the U.S.S.R. has led to exploration of alternative methods, particularly greater intensification of exploitation. The regional variations in the balance between intensive and extensive methods is considerable and is consequently an important aspect of Soviet geographical research. This paper discusses the criteria and methodology for this crucial economic/resource regionalization of the U.S.S.R.  相似文献   

13.
The compilation of statistical data for 269 seismic crustal sections (total length: 81,000 km) which are available in the U.S.S.R. has shown that the preliminary conclusions drawn on relations between the elevation of the surface relief and Bouguer anomalies on one hand and crustal thickness (depth to the M-discontinuity) on the other hand are not fulfilled for the continental part of the U.S.S.R. The level of isostatic compensation has been found to be much deeper than the base of the earth's crust due to density inhomogeneities of the crust and upper mantle down to a depth of 150 km.

The results of seismic investigations have revealed a great diversity of relations between shallow geological and deep crustal structures:

Changes in the relief of the M-discontinuity have been found within the ancient platforms which are conformable with the Precambrian structures and which can exceed 20 km. In the North Caspian syneclise, extended areas devoid of the “granitic” layer have been discovered for the first time in continents. The crust was found to be thicker in the syneclises and anteclises of the Turanian EpiHercynian plate. In the West Siberian platforms these relations are reversed to a great extent.

Substantial differences in crustal structure and thickness were found in the crust of the Palaeo zoides and Mesozoides. Regions of substantial neotectonic activity in the Tien-Shan Palaeozoides do not greatly differ in crustal thickness if compared to the Kazakhstan Palaeozoides which were little active in Cenozoic time. The same is true for the South Siberian Palaeozoides.

The Alpides of the southern areas in the U.S.S.R. display a sharply differing surface relief and a strongly varying crustal structure. Mountains with roots (Greater Caucasus, Crimea) and without roots (Kopet-Dagh, Lesser Caucasus) were found there.

The Cenozoides of the Far East are characterized by a rugged topography of the M-discontinuity, a thinner crust and a less-pronounced “granitic” layer. A relatively small thickness of the crust was discovered in the Baikal rift zone.

The effective thickness of the magnetized domains of the crust as well as other calculations show that the temperature at the depth of the M-discontinuity (i.e., at depths of 40–50 km) is not higher than 300–400° C for most parts of the U.S.S.R.  相似文献   


14.
A major field of research since the 1920s has been methods and theories of economic regionalization. The territorial-production complex is now recognized as a key developmental tool within the framework of economic-planning regions. Recently, there has been a more marked growth of study into problems of natural-resource development, social progress and change in the U.S.S.R. as well as into the spatial structure of other nations, particularly other socialist countries and non-socialist developing countries.  相似文献   

15.
陕西潼关金矿区农田土壤Hg污染的环境效应   总被引:2,自引:0,他引:2  
以潼关金矿区农田土壤Hg污染区的小麦、蔬菜、水果中的Hg含量为重点研究对象,与尚未污染的农田土壤区进行对比,研究土壤Hg污染的农作物效应.评价区小麦样本Hg的超标率为78.57%,小麦Hg超标与土壤Hg污染的关系明显.评价区萝卜样本超标率为40%,叶菜、西红柿、苹果、红薯中样本超标率均为100%,对照区果蔬类也全部超标,但明显低于评价区.评价区农作物Hg超标倍数从大到小依次为:青菜>油麦菜>萝卜叶>西红柿>苹果>红薯>小麦>萝卜.土壤Hg污染的环境效应极为严重,矿区环境污染防治刻不容缓.  相似文献   

16.
The available clay and feldspar reference samples, rather than the frequently used rock reference samples, are suggested as standards for archaeological pottery studies because their trace-element contents are more like those of the artefacts. Such samples may provide a basis for correlating archaeological studies throughout the world. The assumption that bottles of such reference samples should have homogeneous trace-element contents because of the nature of the materials has been confirmed by the analysis of variance of trace -element data by instrumental neutron activation analysis.  相似文献   

17.
Six roches standards de I'USGS : GXR-1 à GXR-6 ont été analysées par activation neutronique instrumentale (INAA) pour le dosage de 17 éléments traces et par fluorescence X (XRF) pour les autres éléments difficiles à doser par activation neutronique. Les travaux précédemment publiés par Gladney et al. ont été pris comme référence en particulier les valeurs recommandées (R.V.) qui sont généralement en bon accord avec nos résultats. Quelques remarques et corrections sont proposées pour expliquer certaines disparités.
Six United States Geological Survey's (USGS) Geochemical Exploration References Samples (GXR) have been analyzed by instrumental neutron activation analysis (INAA) for the determination of seventeen trace elements and by X-ray fluorescence spectrometry (XRFS) for other trace elements difficult to determine by INAA. Our results compare favourably with the values recommended by E.S. Gladney et al. Some suggestions and corrections are proposed to explain some discrepancies.  相似文献   

18.
《Applied Geochemistry》2006,21(5):756-765
The continuous flow elemental analyzer-isotopic ratio mass spectrometer (EA-IRMS) technique provides a significant improvement over conventional extraction methods for the determination of C- and S-isotope ratios in geological materials. It is faster and requires much smaller quantities of material for analysis. Sample preparation is simple, with little or no need for chemical or complete mechanical mineral phase separation, and EA-IRMS sample introduction is rapid. However, because of its simplicity and the fact that data quality depends on the control of a variety of factors, the technique requires rigid adherence to a careful sample analysis protocol.The matching of sample and reference peak heights by sample weight adjustment minimizes non-linearity effects. An accurate calibration should be determined by using standards having a wide range of isotopic compositions, ideally bracketing the samples analysed to both low and high isotopic ratios, and a regular analysis of standards undertaken to maintain the accuracy of the calibration. The calibration equation must be monitored throughout the run by regular analysis of standards, and performance of the Cu-reduction reactor regularly checked to avoid O2 saturation. With this level of attention to analytical detail, measured precision on replicates of isotopic standards is in the order of ±0.1‰ for both C and S isotopic analyses. For S this is a significant improvement over conventional techniques, with 53% of natural samples analysed replicating to better than ±0.1‰.  相似文献   

19.
20.
On October 12, 1962, a joint session of the Presidium of the U.S.S.R. Academy of Sciences and the Collegium of the U.S.S.R. Ministry of Geology and Mineral Reserves adopted a resolution “On the present state of the geological sciences in the U.S.S.R. Academy of Sciences and the U. S. S. R. Ministry of Geology and Mineral Reserves and their prospects for the future.” Important contributions of Russian geologists are acknowledged, but attention is drawn to many shortcomings. Future goals of geological study and work are given in detail. Twenty-one lines of research to be concentrated on are given, covering all phases of geology, geophysics, and geochemistry. In discussing the failings of the geological profession in Russia, it is of interest to note the following comment: “Geological research in other countries is still insufficiently studied and applied, and we are not making adequate use of geologic information from abroad.” The list of the Russian geologists' shortcomings sounds vaguely familiar. —J. R. Hayes  相似文献   

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