湖南柿竹园多金属矿尾矿锡综合利用前景分析

柿竹园有色金属矿山是我国已经探明的地质资源储量最大的钨、钼、锡、铋等多金属矿山，其中锡累计探明储量达48万吨。目前柿竹园仅回收钨、铋、钼、铅、锌、萤石矿等，大量锡随着钨、钼、铋等金属的开采作为废料进入尾矿，因此在尾砂库中保留了丰富的锡资源。对柿竹园尾矿中锡进行回收再利用，必须首先对其综合回收利用途径与前景作出科学评价。本文对柿竹园多金属矿床Ⅲ矿带锡的赋存形式、千吨尾矿库尾矿物质组成特征、锡的丰度、赋存形式和分布进行了研究，在此基础上分析柿竹园尾砂锡综合回收利用的前景。

矿山环境中锑的表生地球化学研究—以贵州半坡锑矿区为例

锑(antimony，Sb)是一种典型的毒害重金属元素。我国作为世界上最主要的锑生产国，有关锑的表生地球化学及锑污染防治研究还很薄弱。贵州省位于我国西南低温成矿域中心，具有高Sb地球化学背景值，是我国重要的锑工业基地，境内分布着大量Sb矿床，锑矿储量居全国第四位。贵州又地处我国西南喀斯特中心区域，岩溶地貌极其发育，生态环境脆弱。由于大规模锑矿资源的开采利用，锑矿区土壤和水体中Sb污染十分突出，并通过水体或食物链对矿区及流域居民健康形成潜在威胁。因此，研究矿山环境中Sb的表生地球化学对于认识Sb污染的环境效应和寻求Sb污染修复方式具有至关重要的意义。 本文以贵州半坡大型锑矿区为研究对象，系统研究了Sb在矿区岩石、固体废弃物、土壤、水体和植物体等表生环境介质中的分布、迁移、富集规律与赋存机制，阐明了矿区Sb的表生地球化学过程规律，评价了矿区围岩、（废）矿石和尾矿砂等样品的产酸潜力，筛选出新的锑潜在超富集植物和超耐受性植物，并获得以下主要认识： （1） 独山半坡锑矿区是典型高锑地质地球化学背景区，不仅矿石中Sb含量很高，而且围岩中Sb含量也远高于上地壳Sb的平均含量。辉锑矿是锑的主要载体和释放源。 （2） 在固体废弃物中，冶炼废渣中Sb含量最高，其次为废石堆和尾砂库。废石中元素特征基本与围岩一致，继承了围岩的元素特征，而尾矿砂由于破碎、浮选过程的改造，其元素含量特征与围岩存在差异。尾砂砂中Sb以中层最富，底层和表层依次降低，与Fe、Al矿物的分布特征相似，这种分布模式主要受氧化还原条件、雨水淋滤、Fe/Al矿物吸附机制等因素控制。尾矿砂中不同相态的锑含量依次为残渣态>碳酸盐结合态>有机物结合态>可交换态>铁锰氧化物结合态，其中生物易利用态Sb的空间分布特征与总Sb分布特征一致。 （3） 所有的（废）矿石样品都具有潜在产酸能力，需要采取必要的措施抑制酸性矿山排水的产生。尾矿砂没有产酸潜力，这与矿石在选冶过程中加入石灰处理和S含量过低等原因有关，这种碱性环境可能有利于锑的表生地球化学活化和迁移。 （4） 研究区土壤受到严重锑污染，土壤中Sb含量高达51~7369 mg/kg，且随深度增加而逐渐降低，底层含量与对照区相近。这种高含量的Sb可能是与锑矿化有关的裸露岩石和土壤的自然风化淋滤过程和采矿、冶炼活动等造成的。研究区土壤中不同相态的Sb含量依次为残渣态>铁/锰氧化物结合态>碳酸盐结合态>有机物/硫化物结合态>可交换态。土壤中Sb的生物有效性很低。土壤中Sb的迁移与As密切相关。 （5） 研究区水体为SO4/HCO3-Ca型，水体中的Sb以溶解态、悬浮态和沉积物形式存在，并通过吸附-解吸附和水流推移方式进行迁移。洪水期和枯水期水体中Sb的扩散迁移机制存在差异，洪水期研究区内水体对岔河下游水体污染危害更大。在枯水期，岔河水体中溶解态Sb含量和沉积物中Sb含量存在显著正相关关系，表明枯水期沉积物和水体界面间达到物质交换平衡。水体的氧化还原条件和pH值控制着水体中Sb的存在形态。沉积物中不同相态Sb含量依次为残渣态>碳酸盐结合态，铁锰氧化物结合态>可交换态，有机物/硫化物结合态。研究区水体中Sb主要受矿区采矿、选冶活动的强烈影响。水体中硫同位素示踪研究发现，岔河下游水体中59%的S来自于矿山硫源的贡献，表明矿山活动严重影响到岔河下游水体水质。 （6） 植物对土壤中Sb的吸收与植物部位和种类有关。大体上地下部分>地上部分，且根>叶片>茎。在农作物中，白菜>甘蓝>辣椒和稻谷。研究发现，土荆芥(Chenopodium ambrosioides Linn.)是新的Sb潜在超富集植物，鬼针草(Bidens pilosa Linn.)、一年蓬(Erigeron annuus (Linn.) Pers.)、佛甲草(Sedum lineare Thun)、凹叶景天(Sedum emarginatum Migo)、灰灰菜(Chenopodium album Linn.)和鼠麹草(Gnaphalium affine D. Don)也能大量富集Sb，并有很强耐受性。 （7） 研究区这种特殊的高Sb地质环境和人为活动的影响，导致表生环境中Sb的高度富集，造成农作物、水体中Sb含量极高，通过食物链和水体严重影响当地居民的身体健康。

碳酸盐岩地区矿山环境地球化学研究

矿山开发引起的环境问题是全球性的问题,越来越受人们的重视,已成为环境地球化学研究的一个重要领域.长期以来,由于AMD有较低pH值和较高的金属含量,加之其对生态环境影响的严重性而备受关注,并取得了若干重要研究进展.在碳酸盐岩地区的矿山环境中,由于其矿石类型、围岩类型以及选矿工艺的不同形成的矿山水体常呈中性,甚至碱性.而这类水体也能有相当含量的重金属,也可导致水文生态系统灾难性的变化.然而,相对酸性矿山水而言,碳酸盐岩矿山环境（碱性水体）重金属元素地球化学研究显得非常薄弱.碳酸盐岩矿山环境作为矿山环境的重要类型之一,人们完全有必要去了解这类环境中重金属元素的迁移释放和沉淀过程.论文通过对低硫化物、高碳酸盐岩矿山周围各种环境要素中重金属矿物学、存在形态的系统研究,辅以硫同位素和REE的示踪手段揭示了碳酸盐岩山区金属矿山开发过程中重金属元素的释放迁移的地球化学过程.

Produção, qualidade e estado nutricional de meloeiro cultivado em Paraipaba-CE utilizando condicionador de solo sob diferentes lâminas de água.

Avaliação do efeito de um polímero hidrorretentor de umidade em diferentes lâminas de irrigação por gotejamento, na cultura do meloeiro híbrido amarelo Gold Mine.

Prevalence of Asthma Symptoms and Associated Factors in Schoolchildren from Brazilian Amazon Islands

Objectives. To determine the prevalence of asthma symptoms among schoolchildren living on two different Brazilian Amazon islands and to identify the risk factors related to this condition. Methods. A cross-sectional study of 400 schoolchildren (5-8 years old) using written questionnaires produced by the International Study of Asthma and Allergies in Childhood, a skin prick test (allergic sensitization), and a stool examination (for helminthic infection). Nonparametric tests were carried out, and the risk factors were identified by logistic regression. Results. the prevalence of active asthma symptoms was markedly higher in children living on Outeiro Island (OI) than those living on Comb Island (CBI) (30.5% and 16.5%, respectively). the logistic regression identified several risk factors of asthma symptoms on CBI: parental history of asthma, night coughing in the past year, and currently have a cat. On OI, the major risk factors were parental history of asthma, personal history of eczema, having two or more older siblings, and night coughing in the past year. the risk factors in common on both the islands were night coughing in the past year and parental history of asthma. Conclusions. the prevalence of asthma symptoms was higher in those with a lifestyle closer to that observed in urban areas (i.e., better sanitation and hygiene), reinforcing the protective effect of a rural environment. Different risk factors were associated with asthma symptoms in schoolchildren living on OI and on CBI. This fact may reflect the environmental individuality and particularities of each island.

Geochemical evidence for atmospheric pollution derived from prehistoric copper mining at Copa hill, Cwmystwyth, mid-Wales. UK

Mighall, T. Abrahams, P. Grattan, J. Hayes, D. Timberlake, S. Forsyth, S. Geochemical evidence for atmospheric pollution derived from prehistoric copper mining at Copa Hill, Cwmystwyth, mid-Wales, UK. The Science of the Total Environment. 2002. 292 pp 69-80

Tectonics Inversions & Emerald Deposits

In spite of the great amount of emerald deposits throughout the world, the priorities in quality and volume of extracted rough material are the sites of Colombia (Muzo and Chivor emerald belts). This sites are know even before the Spanish conquistadores. Emeralds were extracted from Somondoco mine (today Chivor) since 1537 and from Muzo in 1567. Contrariwise to the majority of the emerald deposits of the world, which are associated with granitic rocks, the Colombian emerald deposits are associated with hydrofracturing (the main factor controlling emerald mineralization) and hydrothermal fluids, rich in beryl, chrome and vanadium, induced by a tectonic inversion of the deep Mesozoic backarc basin, which is also responsible of the majority of the petroleum systems of the foredeep and foldbelt areas (maturation of the source-rocks andcreation of structural traps). The host rocks of the emeralds are carbonaceous calsiltites (calcareous schists) rich in organic matter of Lower Cretaceous age, which are cut by calcite veins, which, often, contain emeralds, particularly when they are folded. Indeed, since long time (Cheilletz, A. and Giulliani, G., 1996) suggested a two-stage model for the formation of the Colombian emeralds : (i) Stage I is characterized by décollement planes (early compressional tectonic regime) within the carbonaceous calsiltites, hydrothermal fluid infiltration and wall-rock metasomatic alteration ; (ii) Stage II (late tectonic regime) deforms the previous veins by thrust-related folds (development of stratiform and hydraulic breccia), which are synchronous of the emerald mineralization. The resulting tectonic structures are complex fold patterns characterized by propagation anticlines with emerald veins and emerald hydraulic breccia in the apexes, as in Quipama, Tendenquema and Chivor mines. Otherwise stated, since all emerald exploitations are, presently underground, exhaustive geological and particularly structural studies are required to reduce the probability of disappointments. The color of emeralds is from light green to thick green with obvious pleochroism. They appears with different colors when observed at different angles, especially with polarized light. The emeralds from Coscuez deposits have a homogeneous intensive color and bluish tone. At Muzo deposit, the emeralds have middle or dark green color with yellowish tone. At the Chivor deposits, the emeralds have less intensive green color with slight bluish tone. The typical inclusions are albite and pyrite, as well as long bubbles with three phase-inclusions according the zones of growth and along the crystal shapes.

Nonlinear Acoustics in Underwater and Biomedical Applications: Array Performance Degradation and Time Reversal Invariance

This dissertation describes a model for acoustic propagation in inhomogeneous flu- ids, and explores the focusing by arrays onto targets under various conditions. The work explores the use of arrays, in particular the time reversal array, for underwater and biomedical applications. Aspects of propagation and phasing which can lead to reduced focusing effectiveness are described. An acoustic wave equation was derived for the propagation of finite-amplitude waves in lossy time-varying inhomogeneous fluid media. The equation was solved numerically in both Cartesian and cylindrical geometries using the finite-difference time-domain (FDTD) method. It was found that time reversal arrays are sensitive to several debilitating factors. Focusing ability was determined to be adequate in the presence of temporal jitter in the time reversed signal only up to about one-sixth of a period. Thermoviscous absorption also had a debilitating effect on focal pressure for both linear and nonlinear propagation. It was also found that nonlinearity leads to degradation of focal pressure through amplification of the received signal at the array, and enhanced absorption in the shocked waveforms. This dissertation also examined the heating effects of focused ultrasound in a tissue-like medium. The application considered is therapeutic heating for hyperther- mia. The acoustic model and a thermal model for tissue were coupled to solve for transient and steady temperature profiles in tissue-like media. The Pennes bioheat equation was solved using the FDTD method to calculate the temperature fields in tissue-like media from focused acoustic sources. It was found that the temperature-dependence of the medium's background prop- erties can play an important role in the temperature predictions. Finite-amplitude effects contributed excess heat when source conditions were provided for nonlinear ef- fects to manifest themselves. The effect of medium heterogeneity was also found to be important in redistributing the acoustic and temperature fields, creating regions with hotter and colder temperatures than the mean by local scattering and lensing action. These temperature excursions from the mean were found to increase monotonically with increasing contrast in the medium's properties.

Constraint-based Mining of Frequent Arrangements of Temporal Intervals

The problem of discovering frequent arrangements of temporal intervals is studied. It is assumed that the database consists of sequences of events, where an event occurs during a time-interval. The goal is to mine temporal arrangements of event intervals that appear frequently in the database. The motivation of this work is the observation that in practice most events are not instantaneous but occur over a period of time and different events may occur concurrently. Thus, there are many practical applications that require mining such temporal correlations between intervals including the linguistic analysis of annotated data from American Sign Language as well as network and biological data. Two efficient methods to find frequent arrangements of temporal intervals are described; the first one is tree-based and uses depth first search to mine the set of frequent arrangements, whereas the second one is prefix-based. The above methods apply efficient pruning techniques that include a set of constraints consisting of regular expressions and gap constraints that add user-controlled focus into the mining process. Moreover, based on the extracted patterns a standard method for mining association rules is employed that applies different interestingness measures to evaluate the significance of the discovered patterns and rules. The performance of the proposed algorithms is evaluated and compared with other approaches on real (American Sign Language annotations and network data) and large synthetic datasets.

Atmospheric neutrino oscillation analysis with subleading effects in Super-Kamiokande I, II, and III

We present a search for nonzero θ13 and deviations of sin2θ23 from 0.5 in the oscillations of atmospheric neutrino data from Super-Kamiokande I, II, and III. No distortions of the neutrino flux consistent with nonzero θ13 are found and both neutrino mass hierarchy hypotheses are in agreement with the data. The data are best fit at Δm2=2.1×10-3eV2, sin2θ13=0.0, and sin2θ23=0.5. In the normal (inverted) hierarchy θ13 and Δm2 are constrained at the one-dimensional 90% C.L. to sin2θ13<0.04(0.09) and 1.9(1.7)×10 -3<Δm2<2.6(2.7)×10-3eV2. The atmospheric mixing angle is within 0.407≤sin2θ23≤0.583 at 90% C.L. © 2010 The American Physical Society.

Indication of electron neutrino appearance from an accelerator-produced off-axis muon neutrino beam.

The T2K experiment observes indications of ν(μ) → ν(e) appearance in data accumulated with 1.43×10(20) protons on target. Six events pass all selection criteria at the far detector. In a three-flavor neutrino oscillation scenario with |Δm(23)(2)| = 2.4×10(-3)  eV(2), sin(2)2θ(23) = 1 and sin(2)2θ(13) = 0, the expected number of such events is 1.5±0.3(syst). Under this hypothesis, the probability to observe six or more candidate events is 7×10(-3), equivalent to 2.5σ significance. At 90% C.L., the data are consistent with 0.03(0.04) < sin(2)2θ(13) < 0.28(0.34) for δ(CP) = 0 and a normal (inverted) hierarchy.

Public-public partnerships (PUPs) in water

Water operators need to be efficient, accountable, honest public institutions providing a universal service. Many water services however lack the institutional strength, the human resources, the technical expertise and equipment, or the financial or managerial capacity to provide these services. They need support to develop these capacities. The vast majority of water operators in the world are in the public sector – 90% of all major cities are served by such bodies. This means that the largest pool of experience and expertise, and the great majority of examples of good practice and sound institutions, are to be found in existing public sector water operators. Because they are public sector, however, they do not have any natural commercial incentive to provide international support. Their incentive stems from solidarity, not profit. Since 1990, however, the policies of donors and development banks have focussed on the private companies and their incentives. The vast resources of the public sector have been overlooked, even blocked by pro-private policies. Out of sight of these global policy-makers, however, a growing number of public sector water companies have been engaged, in a great variety of ways, in helping others develop the capacity to be effective and accountable public services. These supportive arrangements are now called 'public-public partnerships' (PUPs). A public-public partnership (PUP) is simply a collaboration between two or more public authorities or organisations, based on solidarity, to improve the capacity and effectiveness of one partner in providing public water or sanitation services. They have been described as: “a peer relationship forged around common values and objectives, which exclude profit-seeking”.1 Neither partner expects a commercial profit, directly or indirectly. This makes PUPs very different from the public–private partnerships (PPPs) which have been promoted by the international financial institutions (IFIs) like the World Bank. The problems of PPPs have been examined in a number of reports. A great advantage of PUPs is that they avoid the risks of such partnerships: transaction costs, contract failure, renegotiation, the complexities of regulation, commercial opportunism, monopoly pricing, commercial secrecy, currency risk, and lack of public legitimacy.2 PUPs are not merely an abstract concept. The list in the annexe to this paper includes over 130 PUPs in around 70 countries. This means that far more countries have hosted PUPs than host PPPs in water – according to a report from PPIAF in December 2008, there are only 44 countries with private participation in water. These PUPs cover a period of over 20 years, and been used in all regions of the world. The earliest date to the 1980s, when the Yokohama Waterworks Bureau first started partnerships to help train staff in other Asian countries. Many of the PUP projects have been initiated in the last few years, a result of the growing recognition of PUPs as a tool for achieving improvements in public water management. This paper attempts to provide an overview of the typical objectives of PUPs; the different forms of PUPs and partners involved; a series of case studies of actual PUPs; and an examination of the recent WOPs initiative. It then offers recommendations for future development of PUPs.

Profitability and the poor: corporate strategies, innovation and sustainability

Based on empirical evidence, the article looks at the implications of private sector participation (PSP) for the delivery of water supply and sanitation to the urban and peri-urban poor in developing countries, with particular reference to Africa and Latin America. More precisely, the article addresses the impact produced by multinational companies’ (MNCs) strategies, in light of the pursuit of profitability, on the extension of connections to the pipeline network. It does so by questioning the assumptions that greater private sector efficiency and innovation, together with contract design, will enable the sustainable extension of service coverage to low income dwellers. The strategies of the major water MNCs are considered both in relation to the global expansion of their operations and the adjustment of local strategies to commercial considerations. The latter might result in identifying proWtable markets, modifying contractual provisions, attempting to reduce costs and increase income, reducing risks and exiting from non-performing contracts. The evidence reviewed allows for re-assessing the relative roles of the public and private sectors in extending and delivering water services to the poor. First, the most far reaching innovative approaches to extending connections are more likely to come from communities, public authorities and political activity than from MNCs. Secondly, whenever MNCs are liable to exit from non-profitable contracts, the public sector has no other option than to deal with external risks aVecting continuity of provision. Finally, market limitations affecting MNCs’ ability to serve marginal populations and access cheap capital do not apply to well-organised, politically led public sector undertakings

Biomonitoring of air pollutants by using lichens (Evernia prunastri) in areas between Kenitra and Mohammedia cities in Morocco.

In this study, Evernia prunastri, a lichen growing in its natural habitat in Morocco was analysed for the concentration of five heavy metals (Fe, Pb, Zn, Cu and Cr) from eleven sites between Kenitra and Mohammedia cities. The control site was Dar Essalam, an isolated area with low traffic density and dense vegetation. In the investigated areas, the concentration of heavy metals was correlated with vehicular traffic, industrial activity and urbanization. The total metal concentration was highest in Sidi Yahya, followed by Mohammedia and Bouznika. The coefficient of variation was higher for Pb and lower for Cu, Zn and Fe. The concentrations of most heavy metals in the thalli differed significantly between sites (p<0.01). Principal component analysis (PCA) revealed a significant correlation between heavy metal accumulation and atmospheric purity index. This study demonstrated also that the factors most strongly affecting the lichen flora were traffic density, the petroleum industry and paper factories in these areas. Overall, these results suggest that the index of atmospheric purity and assessment of heavy metals in lichen thalli are good indicators of the air quality at the studied sites.

Welfare Effort and Poverty from the Monetary and Capabilities Approach: A Cross-Country Analysis in Latin American and the Caribbean (1990-2010)

There is abundant empirical evidence on the negative relationship between welfare effort and poverty. However, poverty indicators traditionally used have been representative of the monetary approach, excluding its multidimensional reality from the analysis. Using three regression techniques for the period 1990-2010 and controlling for demographic and cyclical factors, this paper examines the relationship between social spending per capita —as the indicator of welfare effort— and poverty in up to 21 countries of the region. The proportion of the population with an income below its national basic basket of goods and services (PM1) and the proportion of population with an income below 50% of the median income per capita (PM2) were the two poverty indicators considered from the monetarist approach to measure poverty. From the capability approach the proportion of the population with food inadequacy (PC1) and the proportion of the population without access to improved water sources or sanitation facilities (PC2) were used. The fi ndings confi rm that social spending is actually useful to explain changes in poverty (PM1, PC1 and PC2), as there is a high negative and signifi cant correlation between the variables before and after controlling for demographic and cyclical factors. In two regression techniques, social spending per capita did not show a negative relationship with the PM2. Countries with greater welfare effort for the period 1990-2010 were not necessarily those with the lowest level of poverty. Ultimately social spending per capita was more useful to explain changes in poverty from the capability approach.