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The transformation and concentration of environmental hazardous trace elements during coal combustion 被引量:1
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作者 YAO Duo-xi ZHI Xia-chen 《Journal of Coal Science & Engineering(China)》 2010年第1期74-77,共4页
Studied the content and distribution of 18 environmental hazardous trace elementsin the lignite, fatty coal, anthracite and its burnt products by combustion simulatingexpriment in the one-dismensinal boiler.The transf... Studied the content and distribution of 18 environmental hazardous trace elementsin the lignite, fatty coal, anthracite and its burnt products by combustion simulatingexpriment in the one-dismensinal boiler.The transformations and concentration of 18 traceelements during different coal combustion were discussed.The results show that there aresome content distribution of 18 hazardous trace elements in every burnt product, but thelaw of concentration and dispersion of every trace element during different coal combustionis very different.Experiment results indicate that the transformation and concentrationof trace elements during coal combustion are related to the element contents and occur-rencesof trace elements in raw coal, but are also affected by some man-made factorssuch as the combustion method of boiler, combustion temperature and atmosphere, thetype of precipitators and so on. 展开更多
关键词 environmental hazardous trace elements transformation and concentration coal combustion
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The System Environment Analysis of Teaching Model for Training English Guides of Stone Inscription Relics
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作者 李慧 《海外英语》 2018年第2期252-254,共3页
This study proposes a teaching system environment for the training of English guides of stone inscription relics based on analysis and describes the roles played by each element in this system environment. The element... This study proposes a teaching system environment for the training of English guides of stone inscription relics based on analysis and describes the roles played by each element in this system environment. The elements listed in the system environment can contribute themselves only under the support of the whole system environment. Therefore, the effect of the meaning construction is really the coordination result between the elements of the system environment. It can effectively improve the training efficiency of the training of English guides of stone inscription relics. 展开更多
关键词 system environment environment elements teaching model meaning construction
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Geochemical characteristics of illite clay rocks from the Shihezi Formation in the Hanxing mining area and its sedimentary environment
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作者 Xu Bohui Ding Shuli +1 位作者 Wang Yu Liu Qinfu 《Mining Science and Technology》 EI CAS 2011年第4期495-500,共6页
We studied the geochemical characteristics of illite clay rocks and their importance from the 5hihezi Formation of Late Permian in the Hanxing mining area by means of ICP-M5 and sequential X-ray fluorescence spectrome... We studied the geochemical characteristics of illite clay rocks and their importance from the 5hihezi Formation of Late Permian in the Hanxing mining area by means of ICP-M5 and sequential X-ray fluorescence spectrometry. The results show that the amount of SiO2 is between 53.37% and 61.58% (by weight) and that of Al2O3 22.40% and 31.31% (by weight). The ratio of SiO2/Al2O3 lies between 1.71 and 2.75. The amount of K2O ranges from 1.11% to 2.56% (by weight). The amounts of Fe and Ti are higher than the theoretical values in illite clay rock would indicate. The amounts of some trace elements, such as Ga, As, Ba, Cu, Th and U are higher than their Clark values, while that of another 23 trace elements are found to be dose to their Clark values. The amounts of REE range from 22.59 to 570.54 μg/g, with an average of 163.23μg/g. The ratios of LREE/HREE range from 5.41 to 21.82, with an average of 8.87. These characteristics show that LREE are much richer in content than HREE. The REE distribution patterns of our samples were characterized by clearly negative Ce and Eu anomalies. We analyzed the sedimentary environment of the Hanxing mining area in Late Permian by the characteristic element ratio method. The ratios of Mn/Fe range from 0 to 0.0168, which are lower than those in a marine sedimentary environment. The ratios of Sr/Ba (0.20-0.41) are less than 1. These are all indications that the sediments of the Hanxing mining area in Late Permian form largely a continental sedimentary environment. The sedimentary water is freshwater, a conclusion reached on the basis of the ratios of Th/U (2.66-6.62) and of Ca/(Ca + Fe) (0.01-0.059); the average ratio of Fe2+/Fe3+ is 4.8. The sedimentary water condition is weakly acidic and weakly oxidative-weakly reductive, a conclusion reached on the basis of ratios of Fe2+/Fe3+ (4.8) and of Ceanom (-0.08). 展开更多
关键词 Hanxing mining arealllite Trace elements Geochemical Sedimentary environment
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Environment Elements and Polution Factors Systemativally Identifying and Bolting in Environment Impact Assessment
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作者 SHI Xiaofeng YANG Guodong Xue Juemin Department of Environmental Science,Shanxi University 030006 《Systems Science and Systems Engineering》 CSCD 1998年第3期37-41,共5页
This paper puts forwards a practical way aimed at environmental impact assessment of construction items on basis of systematically classifivcation to deal with environmental favtors through identifying and bolting to ... This paper puts forwards a practical way aimed at environmental impact assessment of construction items on basis of systematically classifivcation to deal with environmental favtors through identifying and bolting to all kinds of environmental factors of construction items 展开更多
关键词 environmental impact assessment environmental elements pollution factor identifying and bolting
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The Systematic Analysis and Assessment of the Environmental Element on Construction Items 被引量:2
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作者 SHI Xiao\|feng Department of Environmental Science, Shanxi University, Taiyuan 030006, China 《Systems Science and Systems Engineering》 CSCD 2000年第3期360-366,共7页
Environmental element has become an important element which restricts the development of economy. The elements in different regions under different environmental conditions restrict the development of economy. In this... Environmental element has become an important element which restricts the development of economy. The elements in different regions under different environmental conditions restrict the development of economy. In this essay, a method, which can quantitatively access the restricting extent of the environmental elements on construction items, is proposed. Since it can systematically analyze and assess the restrictive elements of environmental condition on construction projects, this method can be regarded as a content of the environment. 展开更多
关键词 restrain construction items environment elements
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Effects of soil rock fragment content on the USLE-K factor estimating and its influencing factors
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作者 Miaomiao Yang Qinke Yang +3 位作者 Keli Zhang Chunmei Wang Guowei Pang Yuru Li 《International Soil and Water Conservation Research》 SCIE CSCD 2023年第2期263-275,共13页
Rock fragments are an important component of soil,and their presence has a significant impact on soil erosion and sediment yield.In this paper,the effects of rock fragments in the topsoil profile(RFP)and rock fragment... Rock fragments are an important component of soil,and their presence has a significant impact on soil erosion and sediment yield.In this paper,the effects of rock fragments in the topsoil profile(RFP)and rock fragments on the soil surface(RFS)on the soil erodibility factor(K)were assessed at a global scale.The spatial pattern of the relationship between stoniness and erodibility(RS-K)and its predominant factors were explored through correlation analysis,pattern analysis,and random forest model analysis.The results were as followings:(1)The existence of RFP increased K by 2.84%.The RFS of the mountain land and desert/Gobi reduced K by 18.7%;therefore,once the RFP and RFS were taken into account in the calculation,K was 6.98%lower.(2)The predominant factors of the effect of RFS and the joint effect of RFP and RFS were elevation and slope gradient.The predominant factors of the effect of RFP were annual average precipitation and annual average temperature.(3)In assessing and mapping soil erosion in large regions,special attention should be given to areas with large rock fragment contents,a relatively high altitude,and the presence of steep slope.If rock fragments were not taken into consideration,the mapping results of soil erosion may be biased.This article made the calculation of K more complete and accurate,thereby improving the accuracy of regional soil erosion estimation.This research was of sig-nificance for the investigation of global hydrological effects and simulation of the global soil carbon budget. 展开更多
关键词 Soilerosion Soil erodibility factor Rock fragment Rock cover environmental elements
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Influence factors and variation characteristics of water vapor absorption by soil in semi-arid region 被引量:5
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作者 ZHANG Qiang WANG Sheng +2 位作者 WANG ShanShan ZHAO YingDong WEN XiaoMei 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第11期2240-2251,共12页
The adsorption of water vapor by soil is one of the crucial contributors to non-rainfall water on land surface, particularly over semi-arid regions where its contribution can be equivalent to precipitation and can hav... The adsorption of water vapor by soil is one of the crucial contributors to non-rainfall water on land surface, particularly over semi-arid regions where its contribution can be equivalent to precipitation and can have a major impact on dry agriculture and the ecological environment in these regions. However, due to difficulties in the observation of the adsorption of water vapor,research in this area is limited. This study focused on establishing a method for estimating the quantitative observation of soil water vapor adsorption(WVA), and exploring the effects of meteorological elements(e.g., wind, temperature, and humidity) and soil environmental elements(e.g., soil temperature, soil moisture, and the available energy of soil) on WVA by soil over the semi-arid region, Dingxi, by combining use of the L-G large-scale weighing lysimeter and meteorological observation. In addition, this study also analyzed the diurnal and annual variations of WVA amount, frequency, and intensity by soil, how they changed with weather conditions, and the contribution of WVA by soil to the land surface water budget. Results showed that WVA by soil was co-affected by various meteorological and soil environmental elements, which were more likely to occur under conditions of relative humidity of 6.50% and the diurnal variation of relative humidity was large, inversion humidity, wind velocity of 3.4 m/s,lower soil water content, low surface temperature and slightly unstable atmospheric conditions. There was a negative feedback loop between soil moisture and the adsorption of water vapor, and, moreover, the diurnal and annual variations of WVA amount and frequency were evident—WVA by soil mainly occurred in the afternoon, and the annual peak appeared in December and the valley in June, with obvious regional characteristics. Furthermore, the contribution of WVA by soil to the land surface water budget obviously exceeded that of precipitation in the dry season. 展开更多
关键词 Semi-arid region Water vapor adsorption Micro-meteorological elements Soil environment Water budget
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