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原子荧光光谱法测定地质样品中的痕量锗 总被引：7，自引：1，他引：7
分析了溶矿过程中HNO3、H2SO4、HClO4、H3PO4等对Ge的影响，采用AgNO3滤气装置消除气相干扰，测定了地质样品中的痕量锗，方法检出限为0．06μg／g，用土壤国家一级标准物质GBW 07401～GBW 07408验证方法，结果与标准值相符，其相对标准偏差(RSD，n=12)为3．66％～6．11％。 相似文献
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泡沫塑料富集-石墨炉原子吸收光谱法测定地质样品中微量铊 总被引：2，自引：0，他引：2
采用HF-HClO4-HNO3-HCl溶解样品，泡沫塑料富集-石墨炉原子吸收光谱法测定岩石、土壤、水系沉积物等地质样品中微量铊。以抗坏血酸为基体改进剂，Fe^3＋加入量选择100mg，灰化温度为600℃，原子化温度为1600℃。方法用于测定国家一级标准物质，结果与标准值基本一致。方法精密度（RSD，n=8）为2．88％～6．27％，回收率为95．24％～101．3％，检出限可达0．058μg/g。 相似文献
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电感耦合等离子体原子发射光谱法测定土壤中有效硫 总被引：2，自引：0，他引：2
采用电感耦合等离子体发射光谱法测定土壤中有效硫,浸提剂分别为：Ca（H2PO2）2-2mol／LHAc（中酸性土壤有效硫）,5mol／LNaHCO3（碱性土壤有效硫）？研究了ICP-AES对有效硫测定谱线的选择以及浸提温度、静置时间等对浸提结果的影响,酸性土壤滤液直接经ICP—AES测定,碱性土壤滤液经酸化后再测定。方法检出限分别为0．32mg／kg,通过对国家土壤有效态一级标准物质测试,测定结果基本一致;GBW07415、GBW07413标准物质11次测定的相对标准偏差（RSD）分别为3．66％、2．59％。 相似文献
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富氧空气-乙炔火焰原子吸收光谱法测定地质样品中的钒 总被引：3，自引：0，他引：3
利用测试液中当铝离子浓度超过钒离子浓度两倍以上，铝对钒的吸收信号增感基本恒定，且能较好地克服其它元素的化学干扰，建立了富氧空气-乙炔火焰原子吸收光谱法测定地质样品中痕量钒的方法。方法的检出限LD为0．33mg／L。应用于国家一级地质标准物质中痕量钒的测定，结果与标准值相符。对GBW 07303水系沉积物样品测定6次，ω^-(V)=119．0μg/g，RSD为4．5％。 相似文献
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采用粉末样品压片制样,水系沉积物及土壤国家一级标准物质作为标准,使用经验系数法和散射线内标法校正元素间的吸收增强效应,用X射线光谱仪对土壤样品中的Fe_2O_3、Cao、Cl、S、As、Ba、Br、Ce、Co、Cr、Ni、Cu、Zn等34种主次痕量元素进行测定,用国家一级标准物质GBW07452(GSS-23),GBW07405(GSS-5)和GBW07404(GSS-4)分析检验准确度和精密度,分析结果与标样标准值吻合,除Cl、S、As、Br、Ce、Co、Ni、Th、Sc、Hf、Nb、Nd的精密度小于10.00%以外,其他各元素精密度均在5.00%以内,各元素检出限均满足化探要求。 相似文献
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X射线荧光光谱法同时测定煤中砷硫磷氯 总被引：1，自引：0，他引：1
采用人工混配有限煤炭标准样品粉末直接压片制样，X射线荧光光谱仪同时测量煤中的砷、硫、磷、氯。优化了样品粒度、样品量、助磨剂、制样压力和保压时间等实验条件，用可变α系数法进行基体校正。方法测定范围为As0．0015％-0．0051％、S0．21％-1．44％、P0．003％～0．096％、C10．01％-0．11％；检出限为As 1．2μg／g、S22μg／g、P2．1μg／g、C12．0μg／g。与标准方法对照，结果基本一致。方法快速、简便，满足了煤炭检验需要。 相似文献
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地质样品经HF—HNO3-HCl-HClO4溶解后，用50g／L碳酸钠溶液浸取分离，采用紫外荧光光谱法直接测定上清液的铀含量。浸取时间选择30min，Fe、Zn、Ca、Co、Ni、Cu和Mn等元素留在残渣中不产生干扰。方法精密度（RSD，n=12）为3．37％～7．06％，检出限为0．009μg／g（进样量100μL）。方法参加区域地球化学考核样品的测试，合格率100％，适用于土壤、水系沉积物、岩石及Fe、Zn、Ca、Co、M、Cu和Mn含量较高的样品中痕量铀的测定。 相似文献
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X射线荧光光谱法测定土壤和水系沉积物中碳和氮等36个主次痕量元素 总被引：3，自引：16，他引：3
采用低压聚乙烯镶边垫底的粉末样品压片制样，用ARL ADVANT’XP＋型X射线荧光光谱仪对土壤和水系沉积物样品中C、N、Na2O、MgO、Al2O3、SiO2、P、S、Cl、K2O、CaO、Sc、Ti、V、Cr、Mn、Fe、Co、Ni、Cu、Zn、Ga、Nb、Zr、Y、Sr、Rb、Pb、Th、Ba、As、Br、Hf、La、Ce和Nd等36个组分进行测定。重点研究了C、N等元素的测定务件和痕量元素的背景选择和谱线重叠校正问题。使用经验系数法和康普敦散射作内标校正基体效应。经标准物质校验，结果与标准值吻合。方法的检出限、精密度和准确度能满足多目标地球化学调查样品的分析要求。用GBW 07404土壤国家标准物质进行测试，12次重复测定的精密度（RSD），除N和Cl〈11．0％，其余各组分均〈6．0％。 相似文献
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A. Mesdaghinia M. T. Rafiee F. Vaezi A. Mahvi A. Torabian A. Ghasri 《International Journal of Environmental Science and Technology》2006,2(4):335-342
Jar-test experiments were conducted to study enhanced coagulation effectiveness in removal of disinfection by products (DBPs) from Zayandehrud River at Isfahan Province-the center part of Iran-in 2004. In this study, the removal of suspended and colloidal particles and natural organic matter (NOM) at various coagulant doses and coagulation pHs was assessed through raw and treated water measurements of turbidity, UV254 absorbance, TOC, and dissolved organic carbon (DOC). The trihalomethane formation potential (THMFP) was also determined by a mathematical relationship with TOC. Results indicated that NOM removal was a function of coagulant type, coagulant dose, and pH of coagulation. In general, TOC, DOC, and UV254 absorbance removal enhanced with increasing coagulant dose. However, further increases in coagulant dosage had little effect on disinfection by-products precursors removal. Ferric chloride was consistently more effective than alum in removing NOM. Coagulation pH was appeared to be a determining factor for maximum NOM removal and the removal of DBPs precursors by enhanced coagulation was significantly enhanced at pH 5.5 in comparison with initial pH of water. Furthermore, it is specified that preadjustment of pH with sulfuric acid reduced the coagulant dosage and thus, production of sludge. The reduction in THMFP was consistent with the trends observed for DBPs precursors removal data (i.e. UV254 and TOC data). 相似文献
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V. Frid 《Rock Mechanics and Rock Engineering》1997,30(4):229-236
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地层流体受两大流体系统的控制：压实流和重力流。利用流体势分析系统(简称FPAS)研究地下流体势及压力分布可克服井资料不系统的局限性，有效地进行油气资源的预测评价。由于琼东南盆地地质务件极其复杂，海洋油气勘探程度很低，勘探成本高，石油地质研究水平也比较低，分析认为区内有巨大的油气资源前景，但油气运移方向和路程均不清楚。用地下流体力场和势分析的方法可以统一处理和定量解释油气的运移和聚集规律，明确预测油气运移的主通道，确定有利的油气勘探靶区，显著提高钻探成功率。综合本区剖面、平面流体势及压力特征，结合其他有关地质资料，找出最有利的勘探目的层位。该方法在琼东南盆地松东地区的应用，取得了良好的效果。 相似文献
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《Geoforum》2016
In this paper I argue that there has been a critical shift towards war by conservation in which conservation, security and counter insurgency (COIN) are becoming more closely integrated. In this new phase concerns about global security constitute important underlying drivers, while biodiversity conservation is of secondary importance. This is a significant break from earlier phases of fortress conservation and war for biodiversity. In order to develop a better understanding of these shifts, this paper analyzes the existing conceptual approaches, notably environmental security which seeks to understand how resources cause or shape conflict, and political ecology approaches that focus on the struggles over access to and control over resources. However, this paper indicates the limitations of these existing debates for understanding recent shifts, which require a fresh approach. I chart the rise of the narrative I call poachers-as-terrorists, which relies on the invocation of the idea that ivory is the white gold of Jihad, a phrase which is closely associated with an Elephant Action League (EAL) report in 2012 which claimed Al Shabaab used ivory to fund its operations. This narrative is being extended and deepened by a powerful alliance of states, conservation NGOs, Private Military Companies and international organizations, such that it is shaping policies, especially in areas of US geo-strategic interest in Sub-Saharan Africa. As a result conservation is becoming a core element of a global security project, with significant implications for conceptual debates and for conservation practice on the ground. 相似文献
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V.A. Kashirtsev 《Russian Geology and Geophysics》2018,59(8):975-982
Homologous series of n-alkenes and dimethylalkanes with the odd or even number of carbon atoms in the molecule have been identified in chloroform extracts from the organic matter of Upper Paleozoic deposits of the Vilyui syneclise penetrated by the superdeep well SV-27 at depths below 5 km. It is presumed that these unusual hydrocarbons resulted from the destruction of asphaltene occlusions under severe P-T conditions at great depths and that the hydrocarbon generation began in the zone of postdiagenetic transformations of sediments. This hypothesis was tested in the sections of deposits whose organic matter underwent catagenesis of different grades. On the basis of these results, zones of emergence, transition, and destruction of occlusions have been recognized. 相似文献
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This work describes a laboratory study concerning the adsorption of isopropylxanthate ions onto modified zeolites particles. The separation of the loaded carrier and their removal, from aqueous solutions, was conducted by flocculation followed by dissolved air flotation, DAF. The zeolite employed was a natural sample (approximately 48% clinoptilolite and 30% mordenite) which was previously treated with sodium ions (activation) and modified with copper ions (Cu–Z) before the xanthate ions uptake. Adsorption capacities (qm) for Cu–Z were 0.34 meq g− 1 for the powdered form, and 1.12 meq g− 1 for the floc form. The adsorption capacity for the floc form appears to involve an enhanced electrostatic adsorption due to the positive sites on the floc surface. In all cases, the isopropylxanthate concentration in the treated water was found to be negligible (< 0.04 mg L− 1). The flotation technique showed to be a fast process, requires a low recycle ratio (20%) in air saturated water, and the treated water ended up with a very low residual turbidity (6.8 NTU). It is believed that this adsorption–flotation technique, here named adsorptive particulate flotation, using activated and modified natural zeolite has a high potential as an alternative for pollutants removal (copper and isopropylxanthate ions) from waste mining effluents. 相似文献
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A Practical Procedure for the Measurement of Fragmentation by Blasting by Image Analysis 总被引：1，自引：0，他引：1
Summary. The operation of a digital image analysis system in a limestone quarry is described. The calibration of the system, required
in order to obtain moderately reliable fragmentation values, is done from muckpile sieving data by tuning the image analysis
software settings so that the fragmentation curve obtained matches as close as possible the sieving. The sieving data have
also been used to extend the fragment size distribution curves measured to sizes below the system’s optical resolution and
to process the results in terms of fragmented rock, discounting the material coming from a loose overburden (natural fines)
that is cast together with the fragmented rock. Automatic and manual operation modes of the image analysis are compared. The
total fragmentation of a blast is obtained from the analysis of twenty photographs; a criterion for the elimination of outlier
photographs has been adopted using a robust statistic. The limitations of the measurement system due to sampling, image processing
and fines corrections are discussed and the errors estimated whenever possible. An analysis of consistency of the results
based on the known amount of natural fines is made. Blasts with large differences in the amount of fines require a differentiated
treatment, as the fine sizes tend to be the more underestimated in the image analysis as they become more abundant; this has
been accomplished by means of a variable fines adjustment factor. Despite of the unavoidable errors and the large dispersion
always associated with large-scale rock blasting data, the system is sensitive to relative changes in fragmentation. 相似文献
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The effect of phosphate and glutamic acid on adsorption of aluminium onto a latosol was investigated as a function of pH and ligand concentrations through batch equilibrium experiments. The results showed that adsorption of aluminium by the soil was enhanced after addition of phosphate at low pH, and this promotive effect was gradually eliminated with the increase in pH. The positive effect of phosphate on aluminium adsorption onto latosol was attributed to phosphate-induced surface negative charge and formation of ternary surface complexes involving aluminium and phosphate. While using silica as adsorbent, the inactive surfaces for phosphate, promotion of adsorption of aluminium by phosphate was also found. Then it was proposed that additional aluminium might bind to the phosphate adsorbed onto the silica in the form of surface complexes silica–aluminium–phosphate again, and the mechanism might operate in the soil systems as well. Glutamic acid exhibited no influence on the adsorption of aluminium by the soil at low pH. After increasing the pH, adsorption of aluminium was inhibited especially with the highest addition of glutamic acid, probably owing to weak affinity of complexes between glutamic acid and aluminium to the soil. 相似文献