Investigating the affinities and persistence of VX nerve agent in environmental matrices

Laboratory experiments were conducted to determine environmental variables that affect the affinities and persistence of the nerve agent O-ethyl S-(2-diisopropylaminoethyl) methylphosphonothiolate (VX) at dilute concentrations in environmental matrices. Quantitative analyses of VX and its degradation products were performed using LC-MS. Batch hydrolysis experiments demonstrated an increasing hydrolysis rate as pH increased, as shown in previous studies, but also indicated that dissolved aqueous constituents can cause significant differences in the absolute hydrolysis rate. Adsorption isotherms from batch aqueous experiments revealed that VX has a high affinity for hydrophobic organics, a moderate affinity for montmorillonite clay, and a very low affinity for an iron-oxyhydroxide soil mineral, goethite. The adsorption on goethite was increased with the presence of dissolved organic matter in solution. VX degraded rapidly when dried onto goethite, when specific adsorption was forced. No enhanced degradation occurred with goethite in small amounts of water. These results suggest that aqueous conditions have important controls on VX adsorption and degradation in the environment and a more mechanistic understanding of these controls is needed in order to enable accurate predictions of its long-term fate and persistence.     

Studies on mercury occurrence in inorganic constituents of Polish coking coals

Environmental Science and Pollution Research - During the cokemaking process, a significant amount of mercury occurring in a coal blend is released to the atmosphere. One of the ways of reducing...     

Musculoskeletal Load Assessment of the Upper Limb Positions Subjectively Chosen as the Most Convenient

Work posture is determined by interdependence between work stand design, the necessity to perform given activities, and the anthropometric dimensions of the worker, but it also depends on individual preferences. The aim of the study was to compare the musculoskeletal load of the right upper extremity under conditions of imposed (standard) upper limb position and subjectively chosen ones, and to assess the influence of the changes in magnitude of the external force on the musculoskeletal load in the examined limb positions. Ten healthy male participants took part in the study. Muscular load associated with different upper extremity positions with and without external load were assessed. Musculoskeletal load for standard and subjectively chosen limb positions and two different values of external load were compared by means of theoretical and experimental methods. Results indicate that differences in musculoskeletal load between imposed and subjectively chosen limb positions were not high enough to show statistically significant differences, and the upper limb position chosen by the participant does not always cause the lowest musculoskeletal load.     

The Relationship Between the Difference in Prismatic Refractive Power of an Eye-and-Face Protector and Its Thickness,Radius of Curvature,and Material

With the help of the research results presented here and on the basis of a graphic analysis we aim to prove the existence of a relationship between the difference in prismatic refractive power and the thickness, curvature radius, and type of material used for panoramic oculars in protective spectacles, goggles, and face shields. The difference in the prismatic refractive power is a fundamental optical characteristic of a protective ocular without corrective effect. According to Standard No. EN 165:1995 (European Committee for Standardization, 1995) the difference in the prismatic refractive power is a difference in the prismatic effect at 2 observation points of an eye-protector.     

电子探测系统——边境线安防的重大革命

在这个跨边境恐怖主义活动和非法移民问题多发的年代,世界上的许多国家都在寻找有效保护边境的方法.因此,如何保护被视为"最后一道防线"的周界防护系统国境线成为摆在各国面前的首要问题.     

Efficiency of ASTM Method D4994-89 for Recovery of Enteric Viruses from Biosolids

The ASTM Method D4994-89 has been used in the United States for almost two decades to assess the virological quality of biosolids. However, the efficiency of this method for recovery of different enteric viruses has never been determined. The method was found to recover several different enteroviruses and adenovirus 2 with an efficiency ranging from 18.1 ± 5.5 to 24.6 ± 7.8%.     

Methodology for Identifying Optimal Locations of Water Quality Sensors in River Systems

A method to optimally site river water quality sensors is expanded and applied to a case study river to explore the application of mathematical siting methods to the design of river sampling networks. Fecal coliform contamination due to flooded swine waste lagoons was modeled as it moves downstream, and optimal sensor locations are located by minimizing the objective function of the optimization problem. The results of the simulations are analyzed by varying the number of allowed sampling locations and the simulated contamination event. For the case study application, the model suggests three sampling locations along the modeled river section. These three suggested sensing points did not greatly vary in location for different river flows and contamination events, indicating the robustness of the model results for this specific case study. Generally, the application of mathematical contaminant modeling is a useful and systematic approach to aid the design of river water quality monitoring networks.     

Golden Eagle fatalities and the continental‐scale consequences of local wind‐energy generation

Renewable energy production is expanding rapidly despite mostly unknown environmental effects on wildlife and habitats. We used genetic and stable isotope data collected from Golden Eagles (Aquila chrysaetos) killed at the Altamont Pass Wind Resource Area (APWRA) in California in demographic models to test hypotheses about the geographic extent and demographic consequences of fatalities caused by renewable energy facilities. Geospatial analyses of δ²H values obtained from feathers showed that ≥25% of these APWRA‐killed eagles were recent immigrants to the population, most from long distances away (>100 km). Data from nuclear genes indicated this subset of immigrant eagles was genetically similar to birds identified as locals from the δ²H data. Demographic models implied that in the face of this mortality, the apparent stability of the local Golden Eagle population was maintained by continental‐scale immigration. These analyses demonstrate that ecosystem management decisions concerning the effects of local‐scale renewable energy can have continental‐scale consequences.