Selenium deficiency as a consequence of human activity and its correction

Problems of sustainable development in connection with the change of biogeochemical cycle of selenium and overcoming its deficiency in Russia, Serbia, Belarus and other countries are reported. The history of the biological role of selenium as an essential trace element is discussed. A special program of «Overcoming of selenium deficiency» has been developed by researches of Russia, Serbia and Belarus in view of high morbidity rates for cardiovascular, tumor and endemic diseases affecting the population of both the above and some other countries, including children, prevalence of selenium deficiency among livestock species and aggravation of the environmental situation as a result of man-made processes.     

Hydrogeological conditions for the forming and quality of mineral waters in Serbia

In the past researches conducted on the territory of Serbia, 5 regional geotectonic units have been distinguished with registered occurrences of 230 mineral springs. Recent analyses of the bottled mineral waters quality have not included systematic examinations of micro-components present in these waters. Based on the analyses of the bottled mineral waters (EuroGeoSurveys Geochemistry Expert Group), it has been observed that the water quality is greatly influenced by the chemical composition of igneous intrusions, regardless of the fact that the analyzed waters have been taken from different aquifers (Neogene sediments, limestone, flysch, schist).     

山东郗山-龙宝山地区与碱性岩有关的稀土矿床地质特征及成因

郗山和龙宝山稀土矿具有相似的成矿地质背景、控矿岩体特征及矿床地质特征。燕山早期碱性侵入岩与稀土矿关系密切,稀土矿体主要赋存于杂岩体内及其附近围岩中;稀土元素和同位素研究表明,含矿质的富碱岩浆可能属壳幔混源型,碱性岩浆及成矿物质最初可能都来源于上地幔同一部位,而在岩浆上侵过程中同化混染了地壳物质。郗山稀土矿为单一富轻稀土矿床,矿脉类型以含稀土石英重晶石碳酸盐脉为主,含稀土矿物以氟碳铈矿和氟碳钙铈矿为主,碳酸铈钠矿和菱钙锶铈矿属国内首次发现。龙宝山稀土矿为稀土、金共生矿,矿脉类型主要为石英脉和硅化角砾岩;含稀土矿物主要有氟碳铈矿、氟碳铈镧矿、氟碳钙铈矿;金矿物有自然金、银金矿等。成矿时代稍晚于岩浆岩形成时代,属中生代燕山晚期;矿床成因类型为碱性岩浆期后中-低温热液稀土矿床。     

新疆柴窝堡盆地地下水化学及稳定同位素研究

地下水是维持乌鲁木齐河流域社会经济发展和生态系统的最重要的水源,尤其是柴窝堡盆地因大量开采使得地下水水位下降、湖面萎缩,地下水系统动态特征发生了变化,所以研究区内地下水水流系统及其补径排关系对于深入研究盆地地下水流系统特征和合理开发利用地下水水资源能够提供重要的基础资料,尤其是对调整地下水资源的开采布局具有现实意义。本次研究主要以地质、水文地质背景资料为基础,结合地下水补给环境的差异,利用水化学和水的稳定同位素进行示踪研究,确定了柴窝堡盆地地下水的补给来源和排泄途径,区分出盆地排泄带不同点的补给区,包括东山、南山和西山补给区,对同一补给区又细分出不同的水流系统。     

Synthetic pulsational line profile variations

We have produced simulated time series of high resolution spectroscopy for sdBs. We present the first results of testing classical mode identification techniques. Here, in particular, we analyse the behaviour of individual spectral lines and discuss the results and applicability of the moment method.     

Modeling the Contemporary Stress Field and Deformation Pattern of Eastern Mediterranean

The contemporary stress field in the earth's crust is important and provides insights into mechanisms that drive plate motions.In this study,elastic plane stress finite element modeling incorporating realistic rock parameters was used to calculate the stress field,displacement field,and deformation of the plate interactions in the eastern Mediterranean.Modeled stress data for the African-Arabian-Anatolian plate interactions with fixed European platform correlate well with observed contemporary stress indica...     

Hydrochemical properties of transition zone between fresh groundwater and seawater in karst environment of the Adriatic islands,Croatia

Eastern coast of the Adriatic Sea consists of karstified carbonates. It belongs to the well-known Dinaric karst region. The coast is extremely indented and there are 718 islands with numerous rock crags and reefs. Some of the inhabited islands use their own water resources for public water supply, or plan to do it in the future. Since karst rocks are extremely permeable, the seawater intrudes into underground water resources, thereby forming the wedge. A wide transition zone occurs between this seawater wedge and fresh water aquifers. Consequently, island groundwater reserves turn brackish to a certain extent. In this study, 77 water samples were collected from a wide variety of water resources. Comprehensive statistical and mathematical multivariate analysis of these data was performed. Simple statistical approach showed several useful correlations among some parameters, and more complex multivariate techniques extracted three factors in connection with three natural processes: (1) mixing with the seawater, (2) carbonate dissolution and (3) human influence (pollution) and nitrogen transformation processes. The results of this study demonstrate that in situ measurement of electrical conductivity is adequate for the very rough field estimation of numerous parameters.     

A modeling study of the physical processes affecting the development of seasonal hypoxia over the inner Louisiana-Texas shelf: Circulation and stratification

The physical processes affecting the development of seasonal hypoxia over the Louisiana-Texas shelf were examined using a high-resolution, three-dimensional, unstructured-grid, Finite Volume Coastal Ocean Model (FVCOM). The model was forced with the observed freshwater fluxes from the Mississippi and Atchafalaya Rivers, surface winds, heat fluxes, tides and offshore conditions. The simulations were carried out over a six-month period, from April to September 2002, and the model performance was evaluated against several independent series of observations that included tidal gauge data, Acoustic Doppler Current Profiler (ADCP) data, shipboard measurements of temperature and salinity, vertical salinity and sigma-t profiles, and satellite imagery. The model accurately described the offshore circulation mode generated over the Louisiana-Texas shelf by the westerly winds during summer months, as well as the prevalent westward flow along the coast caused by the easterly winds during the rest of the study period. The seasonal cycle of stratification also was well represented by the model. During 2002, the stratification was initiated in early spring and subsequently enhanced by the intensity and phasing of riverine freshwater discharges. Strong stratification persisted throughout the summer and was finally broken down in September by tropical storms. The model simulations also revealed a quasi-permanent anticyclonic gyre in the Louisiana Bight region formed by the rotational transformation of the Mississippi River plume, whose existence during 2002 was supported by the satellite imagery and ADCP current measurements. Model simulations support the conclusion that local wind forcing and buoyancy flux resulting from riverine freshwater discharges were the dominant mechanisms affecting the circulation and stratification over the inner Louisiana-Texas shelf.     

Geochemical Characteristics of a Veinlet Kupferschiefer Profile from the Lubin Mine, Southwestern Poland

Previous studies have shown that the ascending, oxidizing brines play a very important role in Kupferschiefer mineralization. Fractures could be the pathway of the brines. In order to clarify the influences of the brines on bulk organic matter, aromatic hydrocarbons and Kupferschiefer mineralization, one veinlet Kupferschiefer profile from the Lubin mine, southwestern Poland was studied with the microscopic, geochemical and Rock-Eval methods. The microscopic results indicate that organic matter of the veinlet sample consists dominantly of bitumen. Its extract content is higher than in other samples. The dominant aromatic compounds are naphthalene and alkylated naphthalenes (Na-PAH), which have migrated into the veinlet sample from other sediments. The content of phenanthrene and its methylated derivatives (Ph-PAH) is much lower than in other samples. The reason may be due to their heavier mass than Na-PAH. It is more difficult for Ph-PAH to migrate. The Na-PAH was probably removed from the shale by dist     

浅谈施工企业的成本控制

施工企业工程成本控制的效果对该企业经济效益的好坏重要。为实施有效的成本控制，首先要确定本企业的预算成本；其次，在施工过程中，对各种工程成本进行严格控制；最后，将实际成本与预算成本作比较，分析成本控制的效果，同时提出意见和建议。因此建立本单位的人工、材料、机械消耗量定额等标准，合理确定预算成本，对于提高企业的经济效益意义重大。