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171.
三维虚拟地理环境构建与应用 总被引:2,自引:0,他引:2
可量测三维虚拟地理环境是数字地球应用的基础平台。本文研究了三维虚拟地理环境构建空间几何建模与纹理建模关键技术。提出了一种适用于大规模生产建库的可量测三维虚拟地理环境构建的生产工艺模型和三维虚拟模型数据获取的方法。介绍了三维虚拟地理环境在城市规划、房产经营管理等方面的应用。 相似文献
172.
分光光度法测定雨水中微量过氧化氢的研究 总被引:1,自引:0,他引:1
本文提出了以钛(IV) 过氧化氢 2 (3,5 二溴 2 吡啶偶氮) 5 二乙氨基苯酚(3,5 diBr PADAP)三元配合物体系光度测定雨水中微量过氧化氢的方法,该方法简便,灵敏度和选择性较高,所得结果令人满意 相似文献
173.
福建省森林固定CO2价值评估 总被引:10,自引:0,他引:10
借鉴国内外研究成果,引入“市场逼近系数”,构造森林固定CO2效益经济结构模型,评估福建省森林固定CO2价值,为福建省森林资源的科学管理和资产评估提供了借鉴和参考。 相似文献
174.
Li Ning Li Guangming Yao Zhenya Zhao Jianfu 《Frontiers of Environmental Science & Engineering in China》2007,1(2):190-195
Catalytic wet air oxidation (CWAO) is one of the most promising technologies for pollution abatement. Developing catalysts
with high activity and stability is crucial for the application of the CWAO process. The Mn/Ce complex oxide catalysts for
CWAO of high concentration phenol-containing wastewater were prepared by coprecipitation. The catalyst preparation conditions
were optimized by using an orthogonal layout method and single-factor experimental analysis. The Mn/Ce serial catalysts were
characterized by Brunauer-Emmett-Teller (BET) analysis and the metal cation leaching was measured by inductively coupled plasma
torch-atomic emission spectrometry (ICP-AES). The results show that the catalysts have high catalytic activities even at a
low temperature (80°C) and low oxygen partial pressure (0.5 MPa) in a batch reactor. The metallic ion leaching is comparatively
low (Mn<6.577 mg/L and Ce<0.6910 mg/L, respectively) in the CWAO process. The phenol, CODCr, and TOC removal efficiencies in the solution exceed 98.5% using the optimal catalyst (named CSP). The new catalyst would
have a promising application in CWAO treatment of high concentration organic wastewater.
Translated from Techniques and Equipment for Environmental Pollution Control, 2005, 6(2): 40–44 [译自: 环境污染治理技术与设备] 相似文献
175.
The potential for carbon (C) sequestration was examined in selectedCanadian forest settings and prairie agroecosystems under severalmanagement scenarios. A simple C budget model was developed toquantitatively examine C sequestration potential in living biomass of forestecosystems, in associated forest-product C pools, and in displaced fossil-fuelC. A review of previous studies was conducted to examine C sequestrationpotential in prairie agroecosystems. In the forest settings examined, ourwork suggests that substantial C sequestration opportunities can be realizedin the short term through the establishment of protected forest-C reserves.Where stands can be effectively protected from natural disturbance, peaklevels of biomass C storage can exceed that under alternative managementstrategies for 200 years or more. In settings where it is not feasible tomaintain protected forest-C reserves, C sequestration opportunities can berealized through maximum sustained yield management with harvestedbiomass put towards the displacement of fossil fuels. Because there is afinite capacity for C storage in protected forest-C reserves, harvesting forestbiomass and using it to displace the use of fossil fuels, either directlythrough the production of biofuels or indirectly through the production oflong-lived forest products that displace the use of energy-intensive materialssuch as steel or concrete, can provide the greatest opportunity to mitigategreenhouse gas emissions in the long term. In Canadian prairieagroecosystems, modest C sequestration can be realized while enhancingsoil fertility and improving the efficiency of crop production. This can bedone in situations where soil organic C can be enhanced without relianceupon ongoing inputs of nitrogen fertilizer, or where the use of fossil fuelsin agriculture can be reduced. More substantial C offsets can be generatedthrough the production of dedicated energy crops to displace the use offossil fuels. Where afforestation or reconstruction of native prairieecosystems on previously cultivated land is possible, this represents thegreatest opportunity to sequester C on a per unit-area basis. However,these last two strategies involve the removal of land from crop production,and so they are not applicable on as wide a scale as some other Csequestration options which only involve modifications to currentagricultural practices. 相似文献
176.
对多环芳烃(PAHS)4种理化参数(K;W、Sw。X Vv。)与 LCO的相关关系进行了研究,建立了 4种一元线性回归方程。结果表明,4种参数的相关系数分别为:0.刀66、08083、09488、0.9570,经r检验,后两种属高度显著相关.用所建立的一元线性回归方程对7种PAHS的LC。进行估算,估算值与实测值相比,平均相对误差分别为58.84%、32.23%、1761%、198%,用l和V*.H对LClj进行估算的估算精度也较高。经比较,提出用(。估算P*比对麦穗鱼*CO的新方法。 相似文献
177.
Based on wet air oxidation (WAO) and Fenton reagent, thispaper raises a new low pressure wet catalytic oxidation(LPWCO)which requires low pressure for the treatment of highlyconcentrated and refractory organic wastewater. Compared withgeneral wet air oxidation, the pressure of the treatment(0.1-0.6MPa) is only one of tens to percentage of latter(3.5-10MPa). Inaddition, its temperature is no more than 180℃.Compared withFenton reagent, while H2O2/COD(weight ratio) less than 1.2, theremoval of COD in the treatment is over twenty percents more thanFenton's even the value of COD is more than 14000mg/L. In thispaper, we study the effect factor of COD removal and the mechanismof this treatment. The existence of synergistic effect (catalytic oxidation and carbonization) for COD removal in H2SO4-Fenton reagent system under the condition of applied pressure and heating (0.1-0.6MPa, 104-165℃) was verified. The best condition of this disposal are as follows:H2O2/COD(weight ratio)=0.2-1.0, Fe2+ 0.6×10-3 mol, H2SO4 0.5mol, COD>1×104mg/L, the operating pressure is 0.1-0.6MPa and temperature is 104-165℃. This method suit to dispose the high-concentrated refractory wastewater, especially to the wastewater containing H2SO produced in the manufacture of pesticide, dyestuff and petrochemical works. 相似文献
178.
ZHANG Jian-ying QIU Li-min HE Jia LIAO Yuan LUO Yong-ming College of Environmental Resource Sciences Zhejiang University Hangzhou China. Soil Environment Bioremediation Research Center Institute of Soil Science Chinese Academy of Sciences Nanjing China 《环境科学学报(英文版)》2007,(3)
A total of 198 agricultural soil samples were collected from Zhangjiagang and Changshu in Southern Jiangsu for analysis of 13 polychlorinated biphenyls (PCBs) in order to assess the levels of pollution, sources, area distribution, and potential risk for the environment. All methods were rigorously tested and an adequate quality control was ensured. Only one site had no PCBs residues, and the highest total PCBs concentration in the surface soils was 32.83 ng/g. The average concentration in all the soil samples was 4.13 ng/g, signaling low-level pollution. Tetra-, penta-, and hexa-chlorinated biphenyls were dominant species in soil samples, accounting for more than 75% ofΣPCBs in the soil samples. PCB118 was the most abundant congener in all the samples. The PCB118 was about 20% ofΣPCBs. The soil organic matter content showed only a weak correlation with the levels of all PCB congeners, in which a better correlation was noted for the more volatile lighter PCB congeners than for the heavier homologues. To a certain extent, the sources and land use seemed to influence the levels of PCBs. 相似文献
179.
A new procedure of determining optimal C/N (the rate of carbon source to nitrogen source) of mixed distillers' grains for combined bacteria synergic fermentation is established. At the same time an improved method evaluating bacteria growth, called method of dry cell weighing by filtering is developed. For each combination of C and N , their initial and residual contents before and after fermentation respectively are determined. Then followed the calculation of utilization of C and N sources by the compound bacteria. The optimal C/N is finally located from among the utilization of C and N of several combinations and the weight of produced mass of oven-dried thallus The conditions of fermentation are: inoculum size 10%, temperature 30.0℃, rotational speed 170 r/min, shake culture time 48h. The best results obtained from orthogonal experiments are: maximum mass of oven dried thallus is 14.693g in a liter liquid medium, maximum utilization rate of carbon source is 98.13% and maximum utilization rate of nitrogen is 78.14%. Optimal C/N is 5.1. 相似文献
180.
Quantitativestructure-activitystudyonthereductivedehalogenationpotencyofthehalogenatedaromaticsHuangQingguo;WangLiansheng;Han... 相似文献