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141.
The decomposition of sodium dodecylbenzene sulfonate (SDBS) in water by means of ultrasound irradiation at 20kHz was investigated. Experiments were conducted at surfactant concentrations of 175, 260 and 350 mg l(-1), liquid volumes of 120, 170 and 220 ml, temperatures of 20, 30 and 45 degrees C and applied power of 40, 80 and 125 W. The extent of degradation was followed monitoring substrate and organic carbon concentrations, while hydrogen peroxide concentration was also measured; the latter is a product of water sonolysis due to hydroxyl radical recombination. 80% SDBS conversion was achieved after 120 min of sonication at 125 W and 30 degrees C; nonetheless, SDBS and its degradation intermediates proved difficult to oxidise as only about 20-25% of the initial carbon content was transformed to carbon dioxide. At the initial stages of the reaction, degradation rate appears to be only weakly dependent on the substrate concentration with the rate increasing from 3.1 to 4 mg l(-1)min(-1) with increasing concentration from 175 to 350 mg l(-1). Degradation appears to occur at the bubble-liquid interface through hydroxyl radical-mediated reactions whose role was established by performing experiments in the presence of radical scavengers, namely potassium bromide and sodium benzoate. Degradation rates increased with increasing power and decreasing temperature and volume.  相似文献   
142.
Li CR  Jung KS  Lee SH  Kim A  Park JS 《Chemosphere》2006,63(9):1485-1490
A sandwich enzyme-linked immunosorbant assay (ELISA) was developed to quantitatively detect Bullfrog (Rana catesbeiana) vitellogenin (VTG) levels. This procedure involved a sandwich ELISA using monoclonal antibodies of BVmA1 and BVmA2 against Bullfrog-VTG, and BVmA1 conjugated to horseradish peroxidase as the detection antibody. The assay range was between 9.4 ng/ml and 1200 ng/ml and the recovery of the VTG added to Bullfrog control male serum was 92.0-108.8%. Male Bullfrog was induced by injection 17beta-estradiol (E2) for four weeks and Bullfrog-VTG levels were measured each week. Histological analysis was performed for investigating the correlation of the effect to male reproduction and Bullfrog-VTG level variation depending on E2 dose. After two weeks of E2 exposure, the induced Bullfrog-VTG level was significantly higher than Bullfrog control female (p<0.05). After four weeks of E2 exposure, the rupture and fusion of seminiferous tubule in the testes of male Bullfrog were shown and provided direct evidence that the reproduction of male Bullfrog was affected by estrogenic compounds. Bullfrog-VTG bioassay, using the sandwich ELISA, could be a sensitive and useful tool for quantification of estrogenic principles in aquatic environments.  相似文献   
143.
Bae PH  Hwang YJ  Jo HJ  Kim HJ  Lee Y  Park YK  Kim JG  Jung J 《Chemosphere》2006,63(6):1041-1047
Plasma treatment was evaluated as an alternative clean desizing technology in this work. As indicated by weight loss, O2 plasma treatment efficiently removed sizing agents such as polyvintyl alcohol (PVA), polyacrylic acid esters and their mixture (MIX) on polyethylene terephthalate (PET) fabrics. SEM pictures of the plasma treated samples directly proved the disappearance of the sizing agents. XPS analysis showed apparent changes in chemical composition and functional groups of the PET surface after O2 plasma treatment. Carbon content decreased due to the removal of sizing agents while oxygen content increased. O2 plasma treatment also increased hydrophilic functional groups of sizing agents, which is confirmed by C1s and O1s deconvolution analyses. After O2 plasma treatment, the PET fabric was subjected to conventional desizing process at different temperatures. Except for the PET fabric sized with PVA, plasma-treated fabrics showed more efficient desizing results when compared with untreated fabrics. Furthermore, the desizing effluent from the treated fabric gave lower TOC, COD and BOD values.  相似文献   
144.
The effect of mixing of NH3 and NO on the selective noncatalytic reduction (SNCR) reaction was investigated using a bench-scale reactor. Three different experimental conditions were compared for the removal of NO in the bulk gas with NH3, a reducing agent, by means of mixing and contacting. The temperature that gave the highest NO removal efficiency was about 800°C when NH3 was injected with air or NH3 was premixed and air was injected. It is suggested that control of mixing of the reducing agent and the injection conditions could be a good way to increase NO removal efficiency as well as to lower the reaction temperature. When NH3 was injected with air, the NO removal efficiency increased with increasing injected air flow if the initial NO concentration was low, whereas for high NO concentrations, the NO removal efficiency slightly increased up to an injected air flow rate of 100 ml/min. A proposed mixed-flow model can be used as a prediction tool for the NO removal efficiency covering various conditions of the real SNCR process.  相似文献   
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ABSTRACT: A distributed watershed model combining kinematic wave routing, 1‐D dynamic channel‐flow routing, and 2‐D diffusive overland‐flow routing has been developed to simulate flooding and inundation levels of large watersheds. The study watershed was linked to a GIS database and was divided into an upstream mountainous area and a downstream alluvial plain. A kinematic wave routing was adopted at the mountainous area to compute the discharge flowing into the alluvial plain. A 1‐D dynamic channel routing solving the St. Venant equations by the Preissmann method was performed for the main channel of the alluvial plain, whereas a 2‐D overland‐flow routing solving the diffusion wave equation with the Alternating Direction Explicit scheme was used for floodplains. The above two routings were connected by weir‐link discharge formula. The parameters in the model were calibrated and independently verified by single‐event storms. An example application of flooding/inundation analysis was conducted for the Taichung station and the Woozi depot (Taiwan High Speed Rail). Suggested inundation‐proofing measures ‐ including raising ground surface elevation of the station and depot and building a waterproofing exterior wall and their combination ‐ were investigated. It was concluded that building the waterproofing exterior wall had a strong tendency to decrease peak inundation depth.  相似文献   
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The objective of this study is to estimate the vehicle kilometer traveled (VKT) and on-road emissions using the traffic volume in urban. We estimated two VKT; one is based on registered vehicles and the other is based on traffic volumes. VKT for registered vehicles was 2.11 times greater than that of the applied traffic volumes because each VKT estimation method is different. Therefore, we had to define the inner VKT is moved VKT inner in urban to compare two values. Also, we focused on freight modes because these are discharged much air pollutant emissions. From analysis results, we found middle and large trucks registered in other regions traveled to target city in order to carry freight, target city has included many industrial and logistics areas. Freight is transferred through the harbors, large logistics centers, or via locations before being moved to the final destination. During this process, most freight is moved by middle and large trucks, and trailers rather than small trucks for freight import and export. Therefore, these trucks from other areas are inflow more than registered vehicles. Most emissions from diesel trucks had been overestimated in comparison to VKT from applied traffic volumes in target city. From these findings, VKT is essential based on traffic volume and travel speed on road links in order to estimate accurately the emissions of diesel trucks in target city. Our findings support the estimation of the effect of on-road emissions on urban air quality in Korea.  相似文献   
150.
The objectives of this present study were to assess the effects of varying dilutions, pH, temperature and cations on spermatozoa motile parameters (SMPs) in fish Larimichthys polyactis. Optimal SMPs were observed when emen was diluted in artificial seawater (ASW) at a ratio of 1 to 100, with temperature of 10 degreesC and pH 8.0. The spermatozoa of L. polyactis were immotile in distilled water and motile in solution containing different cations. Maximum SMPs were obtained in each solution containing 0.4 mol NaCI, 0.4 mol KCI, 0.2 mol CaCI2 and 0.2 mol MgCl2. This study provides baseline knowledge of L. polyactis spermatozoa sensitivity of pH, temperature and cationic effects.  相似文献   
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