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31.
Goyal SK 《Environmental monitoring and assessment》2003,89(3):305-314
Sodium arsenite (modified Jacobs and Hochheiser method; hereafter referred as SA), the most widely used manual monitoring method for determination of nitrogen dioxide (NO2) in ambient air, particularly in developing countries has been evaluated and compared with US EPA recommended equivalent method of TGS-ANSA (hereafter referred as ANSA). NO2 concentrations generated from laboratory test atmosphere were analyzed by these two methods and were compared statistically. Laboratory evaluations showed that SA method has high sensitivity to different sampling conditions, which normally vary during actual field monitoring. Hence, correction factors for absorption efficiency were estimated for SA and ANSA methods. Absorption efficiency of NO2 in SA method was found to be much lower (64%) as against the reported value of 82% at the method recommended sampling conditions, whereas for ANSA method, it was found 1.0 as against the reported value of 0.93. After applying derived correction factors, both the methods produced almost similar concentration values of NO2. 相似文献
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33.
分光光度法测定染色废水的色度 总被引:3,自引:0,他引:3
为消除测定染色废水色度的主观误差,采用分光光度法测定染色废水的色度,与稀释倍数法相比,具有精确,重现性好,适用范围广等特点,PH值对色度的测定有明显影响,控制PH值为7.60,测定色度具有可比性。 相似文献
34.
John Boland Olena Kravchuk Wasim Saman Rowan Kilsby 《Environmental Modeling and Assessment》2003,8(2):101-113
The provision of energy for households is a major contributor to greenhouse gas emissions in the domestic sector. There is significant scope for energy savings and thus emission reduction in this sector. This paper constructs a bridge between thermal analysis and environmental assessment in the occupancy stage of the dwelling life cycle, approaching both methods as being on a common system Environment–Dwelling–Inhabitant. The importance of the local level in the thermal analysis and assessment of either a dwelling or an inhabitant's behaviour is demonstrated. It is shown that the researcher can choose between natural experiment, computer experiment and mathematical modelling to analyze the system. Such a choice is discussed for two particular methods of thermal analysis. Thermal Nomograms are the result of mathematical modelling, and the Energy Score Sheet is the result of a computer experiment in energy rating. Despite being developed for the purpose of thermal analysis, these methods can also be utilized for environmental assessment at the local level. The discussion centres on Australian conditions where the majority of the population resides in a relatively benign climate wherein behavioural alterations have significant potential for energy savings and environmental impact. The purpose of the paper is to emphasise benefits apart from energy minimisation to promote the use of energy efficient housing strategies. 相似文献
35.
通过对新疆著名旅游城市吐鲁番的空气环境、水环境、声环境、景观生态环境等环境质量存在的问题进行分析,针对性地提出了相应的环保对策及建议,为吐鲁番市的环境保护工作提供参考。 相似文献
36.
Controlled-release fertilizer(CRF):A green fertilizer for controlling non-point contamination in agriculture 总被引:9,自引:0,他引:9
Fertilizers contribute greatly to high yields but also result in environmental non-point contamination, including the emission of greenhouse gas(N2O) and eutrophication of water bodies. How to solve this problem has become a serious challenge, especially for China as its high ecological pressure. Controlled-release fertilizer(CRF) has been developed to minimize the contamination while keeping high yield and has become a green fertilizer for agriculture. Several CRFs made with special coating technology were used for testing the fertilizer effects in yield and environment through pot experiment and field trial. The result indicated that the CRFs had higher N use efficiency, thus reducing N loss through leaching and volatilization while keeping higher yields. Comparing with imported standard CRFs,the test on CRFs showed similar fertilizer effect but with much lower cost. CRFs application is becoming a new approach for minimizing non-point contamination in agriculture. 相似文献
37.
IntroductionTheo chlorophenolisaverytoxicandpoorlybiodegradablepollutant,whichisusedasanintermediateinthemanufactureofhigherchlorophenolandphenolresinsandforextractingsulphurandnitrogencompoundsfromcoals.Itisalsousedinorganicsynthesis(dyesandpesticide) .Oxidationofo chlorophenolwastewaterincatalyticwetairoxidationisofpracticalinterestsinceawastewatercontainingo chlorophenolover 2 0 0ppmmaynotbetreatedeffectivelybydirectbiologicalmethods.Advancedoxidationprocesses(AOPs)havebeensuccessfullyuse… 相似文献
38.
1IntroductionNovelbiologicalactivatedcarbonandactivatedsludgesystemhasshownitsefectiveabilitytoreduceCODintoxicorganicwastewa... 相似文献
39.
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
40.