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91.
The orthopteran insect Tetrix tenuicornis, collected from polluted and unpolluted areas, was used to study heavy metal accumulation and its impact on stress protein levels and on changes in the number and morphology of chromosomes in mitotic and meiotic cells. During two consecutive years, insects were collected from polluted areas of zinc-lead mine spoils near Boles?aw (Poland) and from unpolluted areas near Busko and Staszów (Poland). T. tenuicornis from the polluted area showed 1.5, 4.03, 4.32 and 41.73 times higher concentrations of copper (Cu), zinc (Zn), lead (Pb) and cadmium (Cd), respectively, than insects of the same species collected from unpolluted areas. Insects exposed to heavy metals showed only small changes, and rather a decrease in the concentration of constitutive and inducible heat shock proteins Hsp70, the level of which increases under stress conditions. A cytogenetic study of T. tenuicornis revealed intra-population anomalies in chromosome number and morphology in mitotic and meiotic cells and the presence of an additional B chromosome in germinal cells. In 50% of females collected from polluted areas, mosaic oogonial mitotic chromosome sets and diploid, hypo- or hypertetraploid, tetraploid, and octoploid chromosome numbers were detected. In turn, 14.6% of males showed a heterozygous deficiency of chromatin in L2 and M3 bivalents in addition to the presence of B chromosomes.  相似文献   
92.
ABSTRACT

This article presents the results of an industrial-scale study (on 400 MWe lignite fired unit) of simultaneous NOx, SO2, and HgT removal in FGD absorber with oxidant injection (NaClO2) into flue gas. It was confirmed that the injection of sodium chlorite upstream the FGD (Flue Gas Desulfurization) absorber oxidize NO to NO2, Hg0 to Hg2+, and enhancing NOx and HgT removal efficiency from exhaust gas in FGD absorber. Mercury removal efficiency grows with the rise of degree of oxidation NO to NO2 and was limited by the phenomenon of re-emission. For NOx removal the most critical parameters is slurry pH and temperature. There was no negative effect on sulfur dioxide removal efficiency caused by oxidant injection in tested FGD absorber. Based on the data provided, NOx and HgT emissions can be reduced by adjusting the FGD absorber operating parameters combined with oxidant injection.  相似文献   
93.
This article addresses the impact of the European Union Emissions Trading System (EU ETS) on Poland’s conventional energy sector in 2008–2020 and further till 2050. Poland is a country with over 80% dependence on coal in the power sector being under political pressure of the European Union’s (EU) ambitious climate policy. The impact of the increase of the European Emission Allowance (EUA) price on fossil fuel power sector has been modelled for different scenarios. The innovation of this article consists in proposing a methodology of estimation actual costs and benefits of power stations in a country with a heavily coal-dependent power sector in the process of transition to a low-carbon economy. Strong political and economic interdependence of coal and power sector has been demonstrated as well as the impact caused by the EU ETS participation in different technology groups of power plants. It has been shown that gas-fuelled combined heat and power units are less vulnerable to the EU ETS-related costs, whereas the hard coal-fired plants may lose their profitability soon after 2020. Lignite power plants, despite their high emissivity, may longer remain in operation owing to low operational costs. Additionally, the results of long-term, up to 2050, modelling of Poland’s energy sector supported an unavoidable need of deep decarbonisation of the power sector to meet the post-Paris climate objectives. It has been concluded that investing in coal-based power capacity may lead to a carbon lock-in of the power sector. Finally, the overall costs of such a transformation have been discussed and confronted with the financial support offered by the EU. The whole consideration has been made in a wide context of changes ongoing globally in energy markets and compared with some other countries seeking transformation paths from coal. Poland’s case can serve as a lesson for all countries trying to reduce coal dependence in power generation. Reforms in the energy sector shall from the very beginning be an essential part of a sustainable transition of the whole nation’s economy. They must scale the power capacity to the future demand avoiding stranded costs. The reforms must be wide-ranging, based on a wide political consensus and not biased against the coal sector. Future energy mix and corresponding technologies shall be carefully designed, matched and should remain stable in the long-term perspective. Coal-based power capacity being near the end of its lifetime provides an economically viable option to commence a fuel switch and the following technology replacement. Real benefits and costs of the energy transition shall be fairly allocated to all stakeholders and communicated to the society. The social costs and implications in coal-dependent regions may be high, especially in the short-term perspective, but then the transformation will bring profits to the whole society.  相似文献   
94.
This article presents an analysis of results of 1035 serious and 341 minor accidents recorded by Poland's National Labour Inspectorate (PIP) in 2005–2011, in view of their prevention by means of additional safety measures applied by machinery users. Since the analysis aimed at formulating principles for the application of technical safety measures, the analysed accidents should bear additional attributes: the type of machine operation, technical safety measures and the type of events causing injuries. The analysis proved that the executed tasks and injury-causing events were closely connected and there was a relation between casualty events and technical safety measures. In the case of tasks consisting of manual feeding and collecting materials, the injuries usually occur because of the rotating motion of tools or crushing due to a closing motion. Numerous accidents also happened in the course of supporting actions, like removing pollutants, correcting material position, cleaning, etc.  相似文献   
95.
Allometry is the knowledge concerning relations between the features of some beings, like animals, or cities. For example, the daily energy rate is proportional to a mass of mammals rise of 3/4. This way of thinking has spread quickly from biology to many areas of research concerned with sociotechnical systems. It was revealed that the number of innovations, patents or heavy crimes rises as social interaction increases in a bigger city, while other urban indexes such as suicides decrease with social interaction. Enterprise is also a sociotechnical system, where social interaction and accidents at work take place. Therefore, do these interactions increase the number of accidents at work or, on the contrary, are they reduction-driving components? This article tries to catch such links and assess the allometric exponent between the number of accidents at work and the number of employees in an enterprise.  相似文献   
96.
对大气污染总量控制规划智能决策支持系统的开发步骤和总体结构做了介绍。并描述了该系统中的知识库系统、模型库系统、数据库系统和图形库系统的设计思想,特别是对知识库的构造进行了较详细的叙述。还介绍了神经网络技术在该系统中的应用。指出大气污染总量控制规划智能决策支持系统将为大气污染总量控制提供更科学、更合理、更有效的规划方案。  相似文献   
97.
城市大气环境质量比较评价分级方法   总被引:6,自引:1,他引:5       下载免费PDF全文
以城市大气环境实测数据为背景,经过Box-Cox变换,选取标准正态分布的代表点,得到大气环境质量分级标准值及对应概率。数据正规化后,从多种因素和总量统计进行大气环境质量综合比较分级,按综合分级值Mij从(0.0~1.0)均分原则,分为清洁级、尚清洁级、轻度污染级、中度污染级、重度污染级和极度污染级。  相似文献   
98.
冬季降雪过程对城市大气气态汞污染的影响   总被引:3,自引:0,他引:3  
童银栋  张巍  胡丹  王学军 《生态环境》2010,19(3):505-508
2009年降雪和非降雪期间对北京西北城区的气态总汞浓度进行了连续采样,比较了降雪期间、非降雪期间的气态总汞浓度日变化过程;降雪期间气态总汞浓度的降低和恢复过程。结果表明,降雪和非降雪期间大气气态总汞浓度的日均值有显著差异,降雪期间气态总汞的平均浓度为5.64ng·m^-3,非降雪期间的平均浓度为7.43ng·m^-3,前者约为后者的70%。降雪后约7h气态总汞浓度恢复到降雪前水平。研究中分析了气象因素(气压、风速、阵风速度、气温和相对湿度)对于气态总汞浓度的影响,结果表明:降雪期间主要受到风速(r=-0.527)和阵风速度(r=-0.574)的影响;非降雪期间主要受到风速(r=-0.691),阵风速度(r=-0.726)和相对湿度(r=0.692)的影响,并且相对湿度的影响与风速的影响相近。降雪和非降雪期间气态总汞的日变化有所差异:非降雪期间气态总汞浓度在午夜和清晨较高,日变化趋势与相对湿度一致;降雪期间气态总汞的日变化没有明显规律。  相似文献   
99.
Environmental Geochemistry and Health - The composition and distribution of airborne particles in different locations in a salt mine were determined in terms of their origin, the distance from the...  相似文献   
100.
Uranium is a very toxic and radioactive element. Removal of uranium from wastewaters requires remediation technologies. Actual methods are costly and ineffective when uranium concentration is very low. Little is known about the enhancement of sorption of uranyl ions by phosphate ions on aluminosilicates. Here, we studied sorption of uranyl acetate on red clay in the presence of phosphates. The concentration of U(VI) ranged 0.0001–0.001 mol/L, whereas the concentration of PO4 3? was constant at 0.0001 mol/L. We designed a new method for the analysis of ternary surface complexes. We observed for the first time a remarkable improvement of U(VI) sorption on red clay under the influence of phosphates. We also found that at least two different ternary surface complexes U(VI)–phosphate–clay are formed in the sorbent phase. The complexation of UO2 2+ cations by phosphate ligands in the sorbent phase was confirmed by the X-ray photoelectron spectra of U 4f electrons.  相似文献   
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