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81.
文章以空气综合污染指数法分析了宝鸡市2006年-2011年的环境空气质量状况,分析结果表明宝鸡市环境空气质量逐年变好。以人均GDP为经济指标,以空气综合污染指数为环境指标,建立经济增长与环境空气质量之间的计量模型,进行环境库兹涅茨曲线实证研究。研究结果表明,宝鸡市经济增长和环境空气质量的关系符合库兹涅茨曲线"拐点"后的下降部分。证明该市2006年-2011年的环境空气质量与人均GDP处于良性发展状态。  相似文献   
82.
为了解农村生活污水处理技术在应用过程中的效果.以重庆地区为例,对重庆市63个村庄的生活污水处理设施进行了调查.根据出水水质和建设成本,对村庄常用的污水处理技术进行经济技术综合比较分析.结果表明,无动力人工湿地较为经济,应用效果并不理想,在经济条件比较薄弱的地区可作为过渡型处理技术加以应用;渠道式生态沟投资较昂贵,不推荐使用;一体化设备投资昂贵,运行管理简单,在经济条件较好的地区可以考虑使用.  相似文献   
83.
计算机模拟研究UO2+2在人体细胞液的形态分布   总被引:1,自引:0,他引:1  
建立了由多种金属离子和小分子配体组成的多相细胞液热力学平衡模型.模拟研究了UO2 2在组织液和细胞液的形态分布及CO2-3、氨三乙酸(NTA)和乙二胺四乙酸(EDTA)浓度对细胞液中UO2 2形态分布的影响.在组织液中,正常生理pH下,当各形态UO2 2总摩尔浓度 [U]= 1.0×10-6 mol/L 或[U]=1.0×10-3 mol/L时,UO2 2均主要以[UO2(CO3)3]4-和[UO2(CO3)2]2-形态存在.在细胞液中,当[U]=1.0×10-6 mol/L时,UO2 2主要以[UO2(CO3)3]4-和[UO2(CO3)2]2-存在;当[U]=1.0×10-3 mol/L,pH为6.0~6.8时,细胞液中存在大量的固相(UO2)3(PO4)2·4H2O,当pH为6.8~7.4时,UO2 2主要以[UO2(CO3)3]4-、[UO2(CO3)2]2-和[(UO2)2CO3(OH)3]-存在.细胞液中(UO2)3(PO4)2·4H2O含量随[U]升高而增加.通过调节细胞液pH和增加细胞液CO2-3浓度均能降低其固相UO2 2配合物含量.在细胞液中增加NTA会增加(UO2)3(PO4)2·4H2O含量,当添加EDTA时会显著降低(UO2)3(PO4)2·4H2O含量.  相似文献   
84.
介绍了新近研制的地震台站体应变观测资料的日常处理系统 ;简要地介绍了该系统及其数据库的结构以及各功能模块的作用。  相似文献   
85.
Macronutrients (P, S, K, Na, Mg, Ca), heavy metals (Fe, Zn, Mn, Cu, Pb, Cr, Ni, Cd,) and Al concentrations as well as values of Ca/Al in the tip, middle and base sections, and sheaths of current year and previous year needles of Pinus massoniana from Xiqiao Mountain were analyzed and the distribution patterns of those elements were compared. The results indicated that many elements were unevenly distributed among the different components of needles. Possible deficiency of P, K, Ca, Mn and Al toxicity occurred in needles under air pollution. Heavy metals may threaten the health of Masson pine. Needle sheaths were good places to look for particulate pollutants, in this case including Fe, Cu, Zn, Pb, Cr, Cd and Al.  相似文献   
86.
Goal, Scope and Background Rapid urbanization and the expansion of industrial activities in the past several decades have led to large increases in emissions of pollutants in the Pearl River Delta of south China. Recent reports have suggested that industrial emission is a major factor contributing to the damages in current natural ecosystem in the Delta area. Tree barks have been used successfully to monitor the levels of atmospheric metal deposition in many areas, but rarely in China. This study aimed at determining whether atmospheric heavy metal deposition from a Pb-Zn smeltery at Qujiang, Guangdong province, could be accurately reflected both in the inner bark and the outer bark of Masson pine (Pinus massoniana L.). The impact of the emission from smeltery on the soils beneath the trees and the relationships of the concentrations between the soils and the barks were also analyzed. Methods Barks around the bole of Pinus massoniana from a pine forest near a Pb-Zn smeltery at Qujiang and a reference forest at Dinghushan natural reserve were sampled with a stainless knife at an average height of 1.5 m above the ground. Mosses and lichens on the surface barks were cleaned prior to sampling. The samples were carefully divided into the inner bark (living part) and the outer bark (dead part) in the laboratory, and dried and ground, respectively. After being dry-ashed, the powder of the barks was dissolved in HNO3. The solutions were analyzed for iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), chromium (Cr), nickel (Ni) and cobalt (Co) by inductively coupled plasmas emission spectrometry (ICP, PS-1000AT, USA) and Cadmium (Cd) and lead (Pb) by graphite furnace atomic absorption spectrometry (GFAAS, ZEENIT 60, Germany). Surface soils (0–10 cm) beneath the sample trees were also collected and analyzed for the selected metals. Results and Discussion Concentrations of the selected metals in soils at Qujiang were far above their environmental background values in the area, except for Fe and Mn, whilst at Dinghushan, they were far below their background values, except for Cd and Co. Levels of the metals, in particular Pb and Zn, in the soils beneath the sample trees at Qujiang were higher than those at Dinghushan with statistical significance. The result suggested that the pine forest soils at Qujiang had a great input of heavy metals from wet and dry atmospheric deposition, with the Pb-Zn smeltery most probably being the source. Levels of Cu, Fe, Mn, Zn, Ni and Pb at Qujiang, both in the inner and the outer bark, were statistically higher than those at Dinghushan. Higher concentrations of Pb, Fe, Zn and Cu may come from the stem-flow of elements leached from the canopy, soil splash on the 1.5 m height and sorption of metals in the mosses and lichens growing on the bark, which were direct or indirect results from the atmospheric deposition. Levels of heavy metals in the outer barks were associated well with the metal concentrations in the soil, reflecting the close relationships between the metal atmospheric deposition and their accumulation in the outer bark of Masson pine. The significant (p<0.01) correlations of Fe-Cu, Fe-Cr, Fe-Pb, Fe-Ni, Pb-Ni, and Pb-Zn in the outer barks at Qujiang again suggested a common source for the metals. The correlation only occurred between Pb and Ni, Cd and Co in the outer barks at Dinghushan, which suggested that those metals must possibly have other uncommon sources. Conclusions Atmospheric deposition of the selected metals was great at Qujiang, based on the levels in the bark of Pinus massoniana and on the concentrations in the soils beneath the trees compared with that at Dinghushan. Bark of Pinus massoniana, especially the outer bark, was an indicator of metal loading at least at the time of sampling. Recommendations and Perspectives The results from this study and the techniques employed constituted a new contribution to the development of biogeochemical methods for environmental monitoring particularly in areas with high frequency of pollution in China. The method would be of value for follow up studies aimed at the assessment of industrial pollution in other areas similar with the Pearl River Delta.  相似文献   
87.
固硫生物型煤   总被引:4,自引:0,他引:4  
研究出生物型煤的生产工艺流程,对型煤和生物型煤的固硫技术进行了研究,成功试验生产出固硫性能优良的生物型煤,为中国煤能源可持续发展利用开辟了新途径。  相似文献   
88.
Biochars’ properties will change after application in soil due to the interactions with soil constituents, which would then impact the performance of biochars as soil amendment. For a better understanding on these interactions, two woody biochars of different surface areas (SA) were physically treated with aluminum oxide (Al-oxide) to investigate its potential influence on biochars’ sorption property. Both the micropore area and mesopore (17~500 Å in diameter) area of the low-SA biochar were enhanced by at least 1.5 times after treatment with Al-oxide, whereas the same treatment did not change the surface characteristics of the high-SA biochar due partly to its well-developed porosity. The enhanced sorption of the pesticide isoproturon to the Al-oxide-treated low-SA biochar was observed and is positively related to the increased mesopore area. The desorption hysteresis of pesticide from the low-SA biochar was strengthened because of more pesticide molecules entrapped in the expanded pores by Al-oxide. However, no obvious change of pesticide sorption to the high-SA biochar after Al-oxide treatment was observed, corresponding to its unchanged porosity. The results suggest that the influence of Al-oxide on the biochars’ sorption property is dependent on their porosity. This study will provide valuable information on the use of biochars for reducing the bioavailability of pesticides.  相似文献   
89.
This paper describes the experimental study of dioxins removal from flue gas from a co-combustion municipal solid waste and coal incinerator by means of a fluidized absorption tower and a fabric filter. A test rig has been set up. The flow rate of flue gas of the test rig is 150-2000 m3/h. The system was composed of a humidification and cooling system, an absorption tower, a demister, a slurry make-up tank, a desilter, a fabric filter and a measurement system. The total height of the absorption tower was 6.5m, and the diameter of the reactor pool was 1.2 m. When the absorbent was 1% limestone slurry, the recirculation ratio was 3, the jet rate was 5-15 m/s and the submerged depth of the bubbling pipe under the slurry was 0.14 m, the removal efficiency for dioxins was 99.35%. The concentration of dioxins in the treated flue gas was 0.1573 x 10(-13)kg/Nm3 and the concentration of oxygen was 11%. This concentration is comparable to the emission standards of other developed countries.  相似文献   
90.
稀土酞菁锰对表面活性剂(LAS)的催化氧化性能研究   总被引:1,自引:0,他引:1  
研究了一种新型含稀土酞菁锰(KCeO2MnPcX)催化剂对水中表面活性剂直链烷基苯磺酸钠(LAS)氧化降解的催化性能,讨论了影响催化氧化反应的各种因素,并确定了最佳反应条件。同时初步探讨了这种催化剂对表面活性剂的催化氧化机理,为处理表面活性剂废水提供了新的途径。  相似文献   
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