考虑未来水资源配置的龙刘水库可调水量研究

论文针对黄河上游水沙关系恶化、水资源供需矛盾加剧等问题,围绕黄河全流域2012—2030年水资源规划的配置结果,以龙羊峡、刘家峡梯级水库联合调度为调控手段,考虑全流域综合供水、防洪、防凌、水资源供需平衡等要求,构建了黄河上游龙羊峡、刘家峡（龙刘）梯级水库联合调度模型,采用自迭代模拟优化算法,分别计算4种情景、4种模式下13个方案的可调水量,最终推荐以水定电模式下的计算结果为最佳模式。结果表明：随着未来需水量的增加,可调水量呈减小趋势,且调水工程的引水量未提高梯级水库的可调水量。研究成果可为黄河上游宽谷河段水沙调控、黄河上游梯级水库群科学规划和调度提供技术支撑。     

等离子体热解气化有机废弃物制氢的关键技术分析

等离子体热解气化有机固体废物制氢是一种先进高效的废物处理及资源化利用技术.首先,本文讨论了等离子体热解气化有机废弃物的机理,也概括了等离子体发生器的类型及其特点,其次分析了等离子体处理固体废弃物的影响因素,认为输入功率和载气类型等是影响等离子体处理的主要因素,最后总结了等离子体处理医疗垃圾、农林生物质、污泥等的应用现状与前景,指出等离子体热解气化固体废弃物是一种很有潜力的制氢方法.     

Eco-friendly approach for leaching out heavy metals from sewage sludge

Sewage sludge contains rich organic matter and nutrients essential for the growth of plants but the presence of toxic heavy metals restricts its land application. To overcome this, the study aims an eco-friendly approach for leaching out heavy metals. Sewage sludge from sewage treatment plant, Chennai, India was characterised. The analysis of total heavy metal concentration was done by digesting in nitric acid and different forms were extracted by community bureau of reference sequential method. Heavy metals: As, Cd, Cr, Cr, Ni, Pb and Zn were determined using inductively coupled plasma optical emission spectrometry Perkin Elmer Optima 5300 DV. The experimental set-up for heavy metal leaching was held for five consecutive days at different concentrations of humic acid (0.1%, 0.5% and 1%) at varied pH (5–9). Results revealed that at the end of fifth day at pH 8, 1% humic acid is capable of leaching out 75.5% cadmium, 66.0% nickel, 52.0% lead, 51.2% zinc, 31.2% copper and 8.5% cadmium from sewage sludge. Statistically positive correlation (0.7088) existed between the percentage of heavy metals leached out and the sum of soluble and reducible fractions. Thus, from ecological point of view, humic acid can be used to leach out heavy metals from sewage sludge serving the need in restoration of soil fertility upon land application.     

顺序注射阻抑动力学光度法测定环境水样中的对苯二酚

在酸性条件下,利用对苯二酚能够阻抑碱性藏花红和溴酸钾反应的原理,联用顺序注射分析技术建立了快速测定环境水样中对苯二酚的新方法。在最佳实验条件下,对苯二酚的线性范围为0.05~1.50μg·m L~(-1),检出限为0.02μg·m L~(-1),完成一次分析循环总的试剂消耗仅为0.125 m L。该方法用于自来水、地表水和河水中对苯二酚的测定,结果与HPLC法所得结果对照,无显著性差异。     

Utilization of aluminum hydroxide waste generated in fluoride adsorption and coagulation processes for adsorptive removal of cadmium ion

Although Al-based coagulation and adsorption processes have been proved highly efficient for fluoride (F) removal, the two processes both generate large amount of Al(OH)₃ solid waste containing F (Al(OH)₃-F). This study aimed to investigate the feasibility of utilizing Al(OH)₃-F generated in Al(OH)₃ adsorption (Al(OH)₃-F_ads) and coagulation (Al(OH)₃-F_coag) for the adsorption of cadmium ion (Cd(II)). The adsorption capacity of Al(OH)₃-F_ads and Al(OH)₃-F_coag for Cd(II) was similar as that of pristine aluminum hydroxide (Al(OH)₃), being of 24.39 and 19.90 mg·g^–1, respectively. The adsorption of Cd(II) onto Al(OH)₃-F_ads and Al(OH)₃-F_coag was identified to be dominated by ion-exchange with sodium ion (Na⁺) or hydrogen ion (H⁺), surface microprecitation, and electrostatic attraction. The maximum concentration of the leached fluoride from Al(OH)₃-F_ads and Al(OH)₃-F_coag is below the Chinese Class-I IndustrialWastewater Discharge Standard for fluoride (<10 mg·L^–1). This study demonstrates that the Al(OH)₃ solid wastes generated in fluoride removal process could be potentially utilized as a adsorbent for Cd(II) removal.     

Speciation of particulate trace metals in sediments of Anarbe reservoir∗

Total concentration and chemical forms of heavy metals in samples of sediment from a drinking water reservoir have been analysed. The result of total metal contest shows Fe and Mn concentration increase along the reservoir, from 4.4% in Fe and 0.07% in Mn in the end part to 6.4% Fe and 0.22% Mn at the dam. However, a decrease in organic matter along the reservoir is observed. In order to test the accuracy of the digestion methods used, a standard reference material was also analysed.

Trace metal concentrations, with exception of Cadmium, Pb and Mn, found in fraction 5 are higher than those observed in the others extractions, Fe, Ni, Zn, Cr and Cu content in non‐residual fraction is found mainly in moderately reducible fraction, but the percentage of this fraction in each metal is very different.     

Wild fruits as a contribution to sustainable rural development: a case study from the Garhwal Himalaya

Garhwal Himalaya is an important source of wild fruit species. These wild fruit trees grow abundantly across an altitudinal gradient of Himalaya and the majority of them bear fruits during summer. Fruit varieties are eaten raw by the local inhabitants of the region and whilst they are a rich source of protein, carbohydrate, fat and other elements, compared to cultivated fruits, they have not yet been considered as a source of alternative food products. About 13 potentially exploitable species of wild fruits and one semi-domesticated species having high potential for exploitation were selected for study; six (Aegle marmelos, Berberis asiatica, Hippophae rhamnoides, Myrica nagi, Rubus ellipticus and Prunus armeniaca) were examined in detail for their economic potential. Among the wild fruits, Hippophae rhamnoides was found to be economically efficient, followed by Aegle marmelos, Rubus ellipticus and Myrica nagi, respectively. Prunus armeniaca, a semi-domesticated and less utilized fruit of the higher Himalaya, provides better economic returns on an annual basis. The authors have recently made an attempt to utilize these wild fruits as a source of income, particularly for poor rural inhabitants and unemployed youths of the region by making a variety of edible products such as jam, jelly, juice, squash, sauce, etc. The enterprise was demonstrated to the people to encourage them to adopt it in the form of a small village-level cottage industry. The present paper discusses the distribution, botany, phenology, yield, ethnobotany, and uses of these species, and the cost-benefit analysis of food products prepared from them.     

Speciation of heavy metals in sediments from the Scheldt estuary,Belgium

A simple three-step sequential extraction procedure was applied to study the speciation of heavy metals in sediment from Scheldt estuary, and their relationship to sediment grain size and organic matter content. The sedimentary metal content was fractionated into carbonate and exchangeable, metals bound to organic matter and residual fractions. Sedimentary total metal content was also determined using an industrial microwave (ETHOS 900) HF/HNO₃ extraction method. The extracts were analysed for metals using inductively coupled plasma atomic emission spectrometry. The bioavailable fraction (exchangeable and metals bound to organic matter) comprised less than the other forms. Residue metals were the dominant form of metals in almost all studied sites. The average total metal content for the studied sites decreased in the order Fe>Cr>Cu>Co>Zn>Pb>Cd. Based on average values for the studied sites, the highest bioavailable metals in sediments were Cd (38%) from Westkapelle, Zn (17%) from Yerseke, Co (12%) from Domburg, Cr (9%) from Vlissingen, Fe and Pb each (2%) from Yerseke, and Cu (1%) from Domburg. Metal recovery was good, with<10% difference between the total metal recovered through the extractant steps and the total metal determined using HF/HNO₃ extract.     

Electrochemical hydride generation of tin(II) and its determination by electrothermal atomic absorption spectrometry with in situ trapping in the graphite tube atomizer

An electrolytic hydride generation system for the determination of tin(II) by means of batch electrochemical hydride generation-electrothermal atomic absorption spectrometry (EcHG-ETAAS) with in situ trapping in a graphite tube atomizer is described. The effects of four permanent chemical modifiers – palladium, tungsten, iridium, and platinum – for graphite tube treatment on analyte absorbance and the effects of four cathode materials, i.e., Pb, Sn, Pb–Sn alloy, and glassy carbon, are checked. Three electrolytes, i.e., nitric acid, sulfuric acid, and hydrochloric acid, are examined as catholyte solutions. The influence of several parameters on EcHG is investigated using multivariate and univariate methods. Interferences of some concomitant ions are evaluated. The calibration curve is linear from 1 to 200?µg?L^?1, with a detection limit of 0.8?µg?L^?1 and a relative standard deviation of 6.2% (n?=?3) for 100?µg?L^?1 Sn(II). The proposed method was successfully applied in the analysis of real environmental water samples and reference materials, and good spiked recoveries over the range of 93.1–115% were obtained. The proposed technique provides a means for developing hydride generation of other elements.     

A comparative study of three different methods for the sequential extraction of heavy metals in soil

Three different methods for the sequential extraction of heavy metals from soil (viz those of Tessier et al. (A. Tessier, P.G. Campbell and N. Bisson (1979). Anal. Chem., 51, 844.), Sposito et al. (G. Sposito, L.J. Lund and A.C. Chang (1989). Soil. Sci. Soc. Am. J., 46, 260.) and Mann and Ritchie (S.S. Mann and G.S.P. Ritchie (1993). Aust. J. Soil Res., 31, 255.)) were examined in terms of the distribution of Cu, Zn and Pb in the soil phases and the bioavailability of these elements in soil. To this end, several samples of soils polluted with metals from a copper mine were fractionated by using the three studied methods and analyzed by atomic absorption spectrometry. The results revealed differences in extraction efficiency among the methods due to the extractant used, or its concentration, and to the soil/solution ratio. The three methods were found to provide accurate heavy metal background contents. However, the method of Tessier et al. is to be preferred for quantifying increased levels of heavy metals on account of its high extraction power.