硫脲介质-石墨炉原子吸收光谱法测定化探样品中微量银

样品经王水分解,硫脲提取,石墨炉原子吸收光谱法测定化探样品中的微量银。方法检出限为0.058 ng/mL;精密度(RSD,n=6)为0.8%～5.4%;回收率为94%～105%。方法经国家一级标准物质验证,测定结果与标准值相符。     

GFAAS法测定地质样品中痕量银

采用石墨炉原子吸收光谱法测定化探样品中痕量银。选择仪器最佳温度程序,采用四酸溶样,硝酸介质,硫脲、铱盐为基体改进剂,国家一级标准样品绘制工作曲线。在取样0．1000g,定容10mL情况下,方法检出限为0．01ug／g,经用国家标准物质验证,测定准确度和精密度比较满意。     

石墨炉原子吸收光谱法测定地质样品中微量银

对石墨炉原子吸收光谱法测定地质样品中微量银进行了研究。样品经四酸溶解,在3mol/L的HCl介质中以EDTA-抗坏血酸溶液作为基体干扰改进剂,用石墨炉原子吸收光谱法测定地质样品中微量银。方法检出限为0.051ng/mL,精密度(RSD,N=11)5.91%~12.83%。能满足地质样品中w(Ag)/10-6=0.03~5范围内银测定的准确度和精密度的要求。     

土壤样品中痕量价态金石墨炉原子吸收光谱法的测定及分离方法实验研究

在前人研究泡塑吸附金分离的基础上,用聚氨酯泡沫塑料吸附,利用石墨炉原子吸收法测定了痕量价态金的含量,探讨了溶矿介质、解脱时间、吸附温度、Fe~(3+)加入量等对测定结果的影响,确定了最佳测定条件,详细讨论了Fe~(3+)在溶矿和吸附过程中的作用,并将该方法用于土壤中痕量价态金的测定。方法检出限为0. 01 ng/g,测定范围为0. 03～300 ng/g,价态金回收率分别是Au~(3+)97. 3%、Au~+95. 8%、Au098. 9%,价态金分离精密度(RSD,n=12)为7. 3%～18. 8%。用石墨炉原子吸收光谱法测定价态金,不但有效地抑制了共存元素的干扰,而且能降低检出限,提高灵敏度和准确度,自动化进样减少了劳动强度,提高了分析测试效率,适合大批量样品的测试。     

泡塑吸附-电感耦合等离子体发射光谱法测定矿石中的金

试样在650℃烧制、王水溶解、泡塑振荡吸附、硫脲解脱,用电感耦合等离子体发射光谱法测定矿石中的金量,克服了原子吸收光谱法对低含量金测定稳定性和精密度差、对高含量金测定分取误差大和返工率高等不足,缩短了分析时间。方法经国家一级标准物质分析验证,结果与标准值相符。对二级标准物质测定的方法精密度(RSD,n=12)为6.45%。方法检出限为0.138μg/g,线性范围宽,适用于矿石中0.2μg/g以上金的测定。     

石墨炉原子吸收光谱法测定化探样中痕量金

样品经王水分解处理,并在Fe~(3+)存在条件下,经泡沫吸附,硫脲解脱,采用石墨炉原子吸收光谱法测定痕量金~([1])。通过对干燥温度及时间、灰化温度及时间、原子化温度设置影响测定结果的实验因素进行筛选,确定了实验室测定化探样品中的痕量金的最佳条件,方法检出限为0.18ng/g。精密度(RSD,n=12)为7.95%~11.56%,经国家一级标准物质分析验证,结果与标准值相符。     

载炭泡塑吸附-电感耦合等离子体发射光谱法测定金矿石的金量

载炭泡塑吸附法对金有良好的吸附性能,但只能用于抽滤吸附不能振荡吸附,分析手续繁杂。本文以载炭泡塑振荡吸附-电感耦合等离子体发射光谱法测定金矿石的金量。样品在650℃高温灼烧2 h,用50%王水和10%氯化铁加热溶解,溶液冷却后加入5%高锰酸钾氧化,用中密度规格的载炭泡塑两次振荡吸附溶液中的金,然后于580℃高温灼烧后以50%王水溶解灰分,直接用ICP-OES测定金量。方法检出限(3σ)为0.002μg/g,精密度(RSD,n=11)小于3.7%。本方法对金的吸附率大于99.9%,测定范围为0.01~90μg/g,对不同类型金矿石的适应性强,解决了以往泡塑吸附法吸附率较低、标准系列与样品需同时预处理的问题,对低含量和高含量样品均有较高的准确度。     

聚氨酯泡塑富集硫脲解脱-石墨炉原子吸收光谱法测定地质样品中金铂

泡沫塑料常用于富集常规地质样品中的铂族元素,而富集后往往用高温灰化法解脱,此法操作繁琐,温度过高易使铂配合物分解为王水难以提取的不溶性残渣,导致测试结果不稳定、效率低;单独使用20 g/L硫脲溶液解脱,测试结果的重现性差。本文对此方法进行改进,采用50%王水封闭溶解试样,氯化亚锡还原,聚氨酯泡塑富集,20 g/L硫脲-20%盐酸溶液解脱,石墨炉原子吸收光谱法测定金和铂。在盐酸-氯化亚锡体系中,吸附温度为20℃,振荡时间为30 min时,金和铂的回收率均在95%以上,金和铂的检出限分别为0.23 ng/g和0.39 ng/g,精密度(RSD,n=10)分别为1.8%～10.3%和1.3%～13.3%。经国家一级标准物质验证,测定值和标准值基本相符。该方法泡塑解脱时无需高温灰化,用王水多次提取,在100℃沸水浴中即可一次完成,样品处理快捷。与高温灰化法相比,提取温度大为降低,分析流程简单,显著提高了单次测样量,且干扰小、空白值低,可以满足除王水难溶的铂矿种外大部分地质样品快速测定的需要。     

Z-2000偏振塞曼石墨炉原子吸收分光光度计测定地球化学样品中痕量金

用φ=50%的王水分解样品,聚氨酯泡沫塑料吸附富集金,10g/L硫脲为解脱剂,偏振塞曼石墨炉原子吸收分光光度计测定痕量金。对干燥、灰化、原子化、净化温度和时间,以及载气流量和灯电流强度进行了讨论;对影响金吸附效果的泡塑载体和王水浓度等因素进行了研究。通过实验得到了Z-2000偏振塞曼原子吸收分光光度计最佳石墨炉分析测试条件。方法检出限为0.3ng/g,回收率为95.0%~101.0%,精密度(RSD,n=12)低于8.0%,经国家一级标准物质(GBW07243~GBW07245)分析验证,结果与标准值相符。     

微波消解等离子体发射光谱和石墨炉原子吸收光谱法联合测定土壤中多元素

采用密闭式微波消解系统处理土壤样品,电感耦合等离子体发射光谱法或石墨炉原子吸收光谱法测定土壤样品中铜、砷、铅、锌、钴、铬、锰、镍、钒9个元素。分别从消解液的选择、用酸量及样品消解量等方面进行消解条件的优化,确定了一个最适合土壤消解的前处理体系。各元素的检出限为0.16～2.52μg/g,回收率为95.2%～106.6%,精密度为2.03%～9.79%(n=7)。方法简单快速,效率高,劳动强度低,是进行土壤中多元素测定的高效方法。     

ZJB(BP)-30A型变频调速高压注浆泵的研制

介绍ZJB（BP）－30A型变频调速高压注浆泵的设计思路、研制过程以及其主要技术参数和性能特点。     

Control of disinfection by products formation potential by enhanced coagulation

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).     

用FPAS分析气势--以琼东南盆地为例

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。     

明沟排水与竖井排灌

本文在分析干旱细土平原区水文地质条件的基础上 ,论述了盐渍化地区在不同排水条件下水中盐份的运移和积聚的过程 ,比较了明沟排水和竖井排灌的优劣 ,从而提出竖井排灌是改良土壤盐渍化 ,防止土壤返盐的有效措施     

Hydrocarbons occluded by asphaltenes

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.     

War,by Conservation

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.     

A Practical Procedure for the Measurement of Fragmentation by Blasting by Image Analysis

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.     

Adsorption of aluminium by a latosol as affected by phosphate and glutamic acid

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.     

Annual stream flow simulation by ARMA processes and prediction by Kalman filter

Algeria is a semi-arid country where water resources are not sufficient to cope with the important socio-economic development demands. Any sustainable development strategy is basically dependent on a rigorous management of water resources potential, which presents a true challenge to be tackled for such countries. Classic mathematical models based on time invariability and ignorance of the stochastic and non-linear nature of hydrological variables are not sufficient for simulation and prediction studies. The present study subscribes to the stochastic hydrological processes modeling and prediction in case of time-varying linear systems through adaptive Kalman filter (KF) methodology. It focuses upon stream flows as a water resources component, which is directly related to the socio-economic development meanwhile it opts for Kalman filter as principal tool of work. The main objective is the application of (KF) technique to model and predict annual streamflow volumes in Northern Algeria and the obtained results are satisfactory.