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41.

52 coal ash samples from individual households were analyzed to determine the pH and the concentrations of four toxic elements: arsenic, cadmium, lead and thallium. The method used was atomic absorption spectrometry with graphite-furnace atomization. The ash samples originated from various coal grades and statistical analysis showed existing correlations between the concentrations of studied elements, pH and the coal grades. The maximum concentrations of arsenic, cadmium, lead and thallium were 50,900, 43,500, 128,900, and 6660 µg/kg, respectively. The results were compared with the published data for the ash of industrial origin.

  相似文献   
42.
The aim of the study was to assess the content, distribution, soil binding capacity, and ecological risk of cadmium and lead in the soils of Malopolska (South Poland). The investigation of 320 soil samples from differently used land (grassland, arable land, forest, wasteland) revealed a very high variation in the metal content in the soils. The pollution of soils with cadmium and lead is moderate. Generally, a point source of lead and cadmium pollution was noted in the study area. The highest content of cadmium and lead was found in the northwestern part of the area—the industrial zones (mining and metallurgical activity). These findings are confirmed by the arrangement of semivariogram surfaces and bivariate Moran’s correlation coefficients. Among the different types of land use, forest soils had by far the highest mean content of bioavailable forms of both metals. The results showed a higher soil binding capacity for lead than for cadmium. However, for both metals, extremely high (class 5) accumulation capacities were dominant. Based on the results, the investigated soils had a low (Pb) and moderate (Cd) ecological risk on living components. Soil properties, such as organic C, pH, sand, silt, and clay content, correlated with the content of total and bioavailable forms of metals in the soils. The correlations, despite being statistically significant, were characterized by very low values of correlation coefficient (r?=?0.12–0.20, at p?≤?0.05). Therefore, the obtained data do not allow to define any conclusions as to the relationships between these soil properties. However, it must be highlighted that there was a very strong positive correlation between the total content of cadmium and lead and their bioavailable forms in the soils.  相似文献   
43.
Objective: This article discusses differences between a side impact procedure described in United Nations/Economic Commission for Europe (UN/ECE) Regulation 129 and scenarios observed in real-world cases.

Methods: Numerical simulations of side impact tests utilizing different boundary conditions are used to compare the severity of the Regulation 129 test and the other tests with different kinematics of child restraint systems (CRSs). In the simulations, the authors use a validated finite element (FE) model of real-world CRSs together with a fully deformable numerical model of the Q3 anthropomorphic test device (ATD) by Humanetics Innovative Solution, Inc.

Results: The comparison of 5 selected cases is based on the head injury criterion (HIC) index. Numerical investigations reveal that the presence of oblique velocity components or the way in which the CRS is mounted to the test bench seat fixture is among the significant factors influencing ATD kinematics. The results of analyses show that the side impact test procedure is very sensitive to these parameters. A side impact setup defined in Regulation 129 may minimize the effects of the impact.

Conclusions: It is demonstrated that an artificial anchorage in the Regulation 129 test does not account for a rotation of the CRS, which should appear in the case of a realistic anchorage. Therefore, the adopted procedure generates the smallest HIC value, which is at the level of the far-side impact scenario where there are no obstacles. It is also shown that the presence of nonlateral acceleration components challenges the quality of a CRS and its headrest much more than a pure lateral setup.  相似文献   

44.
Mine rescuers’ heat load under the same physical effort load (25% of the maximal oxygen uptake), using three types of breathing apparatus, in newly developed heat-removing underwear and outerwear was assessed for typical work conditions of mine rescuers, under milder and harsher ambient conditions of 32 and 38?°C, respectively, both at relative humidity of 85% and air velocity of 1.0?m/s. Expending physical effort at the same load while using different kinds of breathing apparatus resulted in a similar heat load. Under both milder and harsher ambient conditions, heat storage and sweating intensity were greater than the average limit value recommended by hygienic standards, which indicates that the use of breathing apparatus significantly hinders heat exchange with the environment. The developed clothing for mine rescuers was highly rated, and was considered by most people to be better than that used currently.  相似文献   
45.
Environmental Science and Pollution Research - The aims of the study were to investigate the concentration, sources and ecological risk of PAHs (polycyclic aromatic hydrocarbons) in bottom...  相似文献   
46.
The paper presents the results of year-long measurements of radon (222Rn) concentration inside 129 buildings in Poland in relation to the geological conditions of their foundation. The authors took into account the division of the country into tectonic units, as well as the lithology of the rocks forming the bedrock of these buildings. As expected, the highest value of mean annual 222Rn concentration (845 Bq/m3) was recorded in a building situated in the area of the Sudetes, while the highest geometric mean (characteristic of the expected log-normal data distribution) was calculated based on measurements from buildings located within the East-European craton, in the area of Mazury-Podlasie monocline, where it reached 231 Bq/m3. Such results reflect geological conditions - the occurrence of crystalline rocks (especially U- and Ra-enriched granites and orthogneisses) on the surface in the Sudetes, and of young post-glacial sediments containing fragments of Scandinavian crystalline rocks, also enriched with U and Ra, in the area of Mazury-Podlasie monocline. However, the least expected result of the investigations was finding out that, contrary to the hitherto widespread belief, none of the major tectonic units of Poland can be excluded from the list of those containing buildings with mean annual 222Rn concentration exceeding 200 Bq/m3. The mean annual concentration of radon for all the buildings were much higher than the mean concentration value (49.1 Bq/m3) of indoor radon in Poland quoted so far. These results cast a completely new light on the necessity to perform measurements of radon concentration in residential buildings in Poland, no more with reference to small areas with outcrops of crystalline rocks (especially the Sudetes, being the Polish fragment of the European Variscan belt), but for all the major tectonic units within Poland.  相似文献   
47.

Introduction

A myriad of volatile organic compounds (VOCs) released by terrestrial vegetation plays an important role in environmental sciences. A thorough chemical identification of these species at the molecular level is essential in various fields, ranging from atmospheric chemistry to ecology of forest ecosystems. In particular, the recognition of VOCs profiles in a context of plant?Cinsect communication is a key issue for the development of forest protection tools.

Purpose

This work was aimed at the development of a simple, robust and reliable method for the identification of volatiles emitted from plant materials, which can attract or deter pest insects. Specifically, volatiles emitted from the bark of Pinus sylvestris were studied, which might attract the black pine sawyer beetle Monochamus galloprovincialis??a serious pest of the tree and a vector of a parasitic nematode Bursaphelenchus xylophius.

Method

The volatiles from bark samples were collected using a solid-phase micro-extraction technique, and subsequently analysed by gas-chromatography/mass-spectrometry (GC/MS). The characterisation of the volatile fraction was based on the comparison with data in mass spectral libraries, and in most cases, with the available authentic standards. The identified compounds were screened against the available entomological data to select insect attractors.

Results

The identified components included terpenes (??-pinene, ?-3-carene, and para-cymenene), oxygenated terpenes (??-terpineol and verbenone), sesquiterpenes (??-longipinene, longifolene, E-??-farnesene, ??-cadinene and pentadecane), and diterpenes (manoyl oxide and (+)-pimaral). Of these, longifolene and (+)-pimaral are of particular interest as plausible attractors for the M. galloprovincialis beetle that might find application in the construction of insect bait traps.  相似文献   
48.
Environmental Science and Pollution Research - The aim of the study was to (i) investigate the potential of edible mushroom Boletus badius (Fr.) Fr. to accumulate 53 elements from unpolluted acidic...  相似文献   
49.
微生物浓度对SFBR工艺去除营养物的影响   总被引:1,自引:0,他引:1  
采用序半连续式反应器(SequentialFed-batchReactor,简称SFBR,下同。)就不同微生物初始浓度对人工配置废水营养物去除效率的影响进行了研究。探讨了微生物初始浓度对COD、氮化合物(NH4-N和NO3-N)除去和微生物生长的影响。结果表明,当微生物初始浓度为140.4g/L时,COD有最高除去率(69.5%)。当微生物初始浓度≥46.8g/L,总氮除去率可达100%。菌体初始浓度对废水中营养物的去除有利。过高浓度的微生物生长,受营养物和供氧的限制。用一组涉及多个微生物反应的动力学模型,分析了微生物初始浓度对同时去除碳、氮化合物效率和微生物生长的影响。  相似文献   
50.
基质初始浓度对SFBR工艺去除营养物的影响   总被引:1,自引:0,他引:1  
采用序半连续反应器就新鲜废水中COD/N比对COD、氮化合物去除效率和微生物生长的影响进行了研究。结果表明,新鲜废水中的COD/N比对COD和总氮去除率有明显的影响。当COD/N比由2.5增至12.5时,COD去除率由44.0%增至75.8%,总氮去除率从63.4%增至99.8%,然而,加料废水中COD/N比对微生物生长没有明显的影响。用一组涉及多个微生物反应的动力学模型,分析了COD/N比对同时去除碳、氮化合物效率和微生物生长的影响。  相似文献   
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