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101.
Abstract

Comprehensive field studies were initiated in 2002 to measure emissions of ammonia (NH3), hydrogen sulfide (H2S), carbon dioxide (CO2), methane (CH4), nonmethane hydrocarbons (NMHC), particulate matter <10 µm in diameter, and total suspended particulate from swine and poultry production buildings in the United States.

This paper focuses on the quasicontinuous gas concentration measurement at multiple locations among paired barns in seven states. Documented principles, used in air pollution monitoring at industrial sources, were applied in developing quality assurance (QA) project plans for these studies. Air was sampled from multiple locations with each gas analyzed with one high quality commercial gas analyzer that was located in an environmentally controlled on-farm instrument shelter. A nominal 4 L/min gas sampling system was designed and constructed with Teflon wetted surfaces, bypass pumping, and sample line flow and pressure sensors. Three-way solenoids were used to automatically switch between multiple gas sampling lines with ≥10 min sampling intervals. Inside and outside gas sampling probes were between 10 and 115 m away from the analyzers. Analyzers used chemiluminescence, fluorescence, photoacoustic infrared, and photoionization detectors for NH3, H2S, CO2, CH4, and NMHC, respectively. Data were collected using personal computer-based data acquisition hardware and software. This paper discusses the methodology of gas concentration measurements and the unique challenges that livestock barns pose for achieving desired accuracy and precision, data representativeness, comparability and completeness, and instrument calibration and maintenance.  相似文献   
102.
Capturing of odorous compounds such as toluene vapor by a particulate-activated carbon adsorbent was investigated in a gas-solid cyclone, which is one type of mobile beds. The test cyclone was early modified with the post cyclone (PoC) and a spiral flow guide to the vortex finder. The proposed process may contribute to the reduction of gases and dust from industrial exhausts, especially when dealing with a low concentration of odorous elements and a large volume of dust flow. In this device, the toluene capturing efficiency at a 400 ppm concentration rose up to 77.4% when using activated carbon (AC) particles with a median size of 27.03 μm. A maximum 96% of AC particles could be collected for reuse depending on the size and flow rate. The AC regenerated via thermal treatment showed an adsorption potential up to 66.7% throughout repeated tests.

Implications: VOCs and particles have been of interest both in industrial field and public indoor spaces. In this study, a post cyclone (PoC) that utilizes a residual vortex from the mother cyclone was modified by inserting a flow guide and was applied to capture toluene vapor. The device of modified post-cyclone system can be used effectively in simultaneous treatment of gas-solid flow.  相似文献   
103.
Recent air pollution legislation, introduced as a Clean Air Act into New South Wales, the most populous and most heavily industrialized Australian State relies mainly upon the establishment of maximum limits of emission of air impurities. Regulations made under the Act set out the first of a series of such limits which cover the more commonly encountered pollutants. Other limits will be included later as knowledge is accumulated but, in the meantime, where standards have not been fixed the "best practicable means" of controlling air pollution must be used. To facilitate administration and to provide financial support for scientific and engineering services in the form of the Air Pollution Control Board, industries of significant air pollution potential have been designated as scheduled premises and pay annual license fees. Further technical support for the legislation is provided by an Air Pollution Advisory Committee.  相似文献   
104.
The occurrence of some veterinary medicines in the livestock wastewater plants (WWTPs) was investigated. This investigation represented the occurrence of veterinary medicines to treat in the livestock WWTPs or be discharged into the water system in Korea since the sampling sites were widely distributed across the nation and samples were collected from the 11 livestock WWTPs. Nine antibiotics, two analgesics, and two disinfectants occurred in the livestock wastewater plants (WWTPs). From 11 livestock WWTP influents, chlortetracycline, oxytetracycline, acetylsalicylic acid, and disinfectants frequently occurred with the high concentrations. Meanwhile, sulfamethoxazole, erythromycin-H2O, and trimethoprim did not occur during sampling periods. The values for log Kow of each chemical showed a high correlation with the number of hydrogen bonding acceptors and were important parameters to estimate and understand the biodegradability and toxicity of a compound in the environment. The biodegradability of each compound was proportional to the hydrophilicity of each compound and the toxicity was proportional to the number of hydrogen bonding acceptors of each compound. The expected introductory concentration (EIC), predicted exposure concentration (PEC), and hazard quotient showed that the livestock WWTP effluents were hazardous to ecosystems.  相似文献   
105.
Scholars have proposed the analytical concept of the environmental state, a state where government actively addresses negative environmental externalities of economic activities. The mapping of environmental regulatory expansion in Western countries has been central in recent attempts to identify the environmental state empirically. Surprisingly little is known, however, when it comes to the environmental regulatory expansions in non-Western countries. Are there similar trends towards the emergence of environmental states in the non-West as well? From analysing data covering 25 policies in 37 countries, it appears that regulatory expansion has also occurred in the non-Western world, and the distinction between the West and the non-West has been reduced over time. There are non-Western countries among environmental pioneers, and there is some evidence for the trend of global convergence. Future research on environmental states should take into account emerging environmental states in the non-West.  相似文献   
106.
The dose rates for six marine organisms, pelagic fish, benthic fish, mollusks, crustaceans, macroalgae, and polychaete worms, representative in marine ecosystems, have been predicted by the equilibrium model with the measured seawater activity concentrations at three locations around the Fukushima Daiich nuclear power plant after the accident on March 11, 2011. Model prediction showed that total dose rates for the biota in the costal sea reached 4.8E4 μGy/d for pelagic fish, 3.6E6 μGy/d for crustaceans, 3.8E6 μGy/d for benthic fish, 5.2E6 μGy/d for macroalgae, 6.6E6 μGy/d for mollusks, and 8.0E6 μGy/d for polychaete worms. The predicted total dose rates remained above the UNSCEAR’s (United Nations Scientific Committee on the Effect of Atomic Radiation) benchmark level (1.0E4 μGy/d for an individual aquatic organism), for only the initial short period, which seems to be insufficiently long to bring about any detrimental effect on the marine biota at the population level. Furthermore, the total dose rates for benthic fish and crustaceans approximated using the measured activity concentration of the biota and bottom sediment was well below the benchmark level. From these results, it may be concluded that the impact of the ionizing radiation on the marine biota around the Fukushima NPP as a consequence of the accident would be insignificant.  相似文献   
107.
转Bt基因克螟稻秸杆对淹水土壤细菌群落的影响   总被引:7,自引:0,他引:7  
在实验室条件下通过秸杆还土试验比较了克螟稻Bt基因表达最高期秸杆和同一时期亲本稻秸杆的添加对淹水土壤可培养厌氧细菌数量和细菌群落组成的影响 .结果表明 ,与亲本对照相比 ,培养初期克螟稻秸杆的添加对淹水土壤厌氧发酵性细菌、产氢产乙酸细菌、反硝化细菌和产甲烷细菌的数量产生了显著性影响 ,但培养后期这种显著性差异基本消失 .PCR 变性梯度凝胶电泳 (DGGE)指纹图谱和主成份分析 (PCA)结果表明 ,两种秸杆处理土壤细菌群落组成在培养的第 3周和第 5周达到显著性差异 ,随着培养时间的延伸 ,两种秸杆处理土壤间细菌群落组成的差异逐渐减小 .到培养的第 1 1周 ,两种秸杆处理土壤间细菌群落组成的差异基本消失 .尽管如此 ,在培养的整个过程中 ,秸杆处理土壤中可培养厌氧性细菌数量和土壤细菌群落的组成均与纯土对照存在显著性差异 .试验结果表明 ,在实验室培养的条件下 ,没有观察到转Bt基因克螟稻秸杆对淹水土壤微生物明显的长期负面影响  相似文献   
108.
109.
110.
Soil blocks from 18 paddy fields around three Korean nuclear power plant sites were put into lysimeters. Greenhouse experiments were carried out to investigate the (137)Cs transfer from these paddy soils to rice plants for its deposition at different growth stages. A solution of (137)Cs was applied to the flooded lysimeters at 2-3 different stages. The applied (137)Cs was mixed with the topsoil only at the pre-transplanting application. The transfer was quantified with a transfer factor based on the unit-area deposition (TF(a), m(2)kg(-1)-dry). The TF(a) in the pre-transplanting application showed a remarkable variation with the soils. However, the differences in the mean values among the study sites were not statistically significant. The straw TF(a) was 2-3 times higher than the corresponding seed value. The early-tillering stage and booting stage applications resulted in a higher transfer than the pre-transplanting application by factors of, on an average, 2 and 16 for the straws, and 3 and 25 for the hulled seeds, respectively. The (137)Cs transfer was found to correlate negatively with the soil pH and positively with the organic matter content. Based on the present results, the representative (137)Cs TF(a) values for the rice are proposed for use in the whole of Korea for the deposition at three different growth stages.  相似文献   
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