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151.
The objective of this research is to evaluate all the critical reaches in a cockpit and determine the visual sufficiency of a cockpit to accommodate 90% of potential pilots. While mismatches of measurements with cockpit dimensions are revealed, proposals are made to improve cockpit ergonomics. Regression models were generated to predict and assure adequate exterior vision. Mean, lower and upper control limits of all measurements were found acceptable except eye level. There are very strong positive relationships between stature and eye level (R2?=?0.972, p?R2?=?0.994, p?SD smaller than the eye level mean or seating adjustment limits in height may be changed. In general, cockpit design is acceptable in terms of fit/reach accommodation for pilots, except eye level and visual variables that could be solved by better seat adjustments.  相似文献   
152.
Two‐dimensional simulation of highly heterogeneous domains, especially those with disparate length scales, roughness conditions, and geometries, often leads to challenges such as long computation times and numerical instability. Simulation of challenging domains is often needed to guide flood management and environmental regulation agencies in operation and potential domain modifications. This work evaluates the ability of a two‐dimensional unsteady hydrodynamic model to represent long‐duration transient flows over a domain with highly heterogeneous roughness, geometric characteristics, and length scales through bed roughness representation. The domain includes 13 km of Cache Creek and the 14.5 km2 Cache Creek Settling Basin, which traps both sediment and mercury. Calibration under different bed roughness methods, validation, and modeling results of bathymetric modification scenarios are presented. The modeling approach's performance supports its application as a tool for management of similar domains, such as settling basins, leveed floodplains, and reservoirs. Accurate representation of flow dynamics can also inform environmental management that involves transport of sediments, nutrients, and heavy metals. This study found that a two‐dimensional unsteady flow model can accurately represent long‐duration transient flow in a large settling basin with highly heterogeneous characteristics without parsing of the domain or flow events simulated.  相似文献   
153.
This paper studies free-riding incentives on common environmental resources in an incomplete information repeated game where abatements are perishable and perfect substitutes. Two contrasting types of perfect Bayesian equilibria emerge: For high discount factors, or low discount factors but “pessimistic” prior beliefs, the inclusion of incomplete information has no impact on the pattern of abatements. Otherwise the countries attempt to use their private information strategically and the game becomes a war of attrition. This generates an outcome where the “pessimistic” country unilaterally abates forever, and another which involves delay until the first abatement if both countries are “optimistic”.  相似文献   
154.
Removal of textile dyes from water by the electro-Fenton process   总被引:5,自引:0,他引:5  
An environmentally friendly electrochemical treatment, electro-Fenton process, was applied to the depollution of a synthetic dismissal composed of three dyes, yellow drimaren, congo red and methylene blue, frequently used in textile and dyehouses. Here, we show that those dyes and their mixture are quickly degraded under current controlled electrolysis conditions, leading to an almost complete mineralization. The results show the efficiency of electro-Fenton process to quickly degrade aqueous effluents polluted by synthetic organic dyes.  相似文献   
155.
Degradation of diuron by the electro-Fenton process   总被引:2,自引:0,他引:2  
The degradation of the herbicide diuron has been undertaken by electrochemical advanced oxidation in aqueous solution. This process generates catalytically hydroxyl radicals that are strong oxidizing reagents for the oxidation of organic substances. Hydroxyl radicals degrade diuron in less than 10 min. Kinetic results evidence a pseudo-first-order degradation, with a rate constant of reaction between diuron and hydroxyl radicals of 4.8x109 M–1 s–1. Several degradation products were identified by chromatography-mass spectrometry (LC-MS). The mineralization degree of a 1.7x10–4 M diuron solution reached 93% at 1,000 coulombs.  相似文献   
156.
Selvi M  Gül A  Yilmaz M 《Chemosphere》2003,52(1):259-263
The 96-h LC(50) value of cadmium chloride (CdCl(2).H(2)O), a metal salt widely used in industry, was determined in the water frog (Rana ridibunda Pallas, 1771). The experiments were conducted in two series and a total of 140 frogs were used to determine acute toxicity. In addition, behavioral changes in the water frog were determined for each cadmium chloride concentration. Data obtained from the cadmium chloride investigation were evaluated by using the probit analysis statistical method and the 96 h LC(50) value for water frog was estimated to be 51.2 mg/l.  相似文献   
157.
Recently, a comprehensive air quality modeling system was developed as part of the Southern Appalachians Mountains Initiative (SAMI) with the ability to simulate meteorology, emissions, ozone, size- and composition-resolved particulate matter, and pollutant deposition fluxes. As part of SAMI, the RAMS/EMS-95/URM-1ATM modeling system was used to evaluate potential emission control strategies to reduce atmospheric pollutant levels at Class I areas located in the Southern Appalachians Mountains. This article discusses the details of the ozone model performance and the methodology that was used to scale discrete episodic pollutant levels to seasonal and annual averages. The daily mean normalized bias and error for 1-hr and 8-hr ozone were within U.S. Environment Protection Agency guidance criteria for urban-scale modeling. The model typically showed a systematic overestimation for low ozone levels and an underestimation for high levels. Because SAMI was primarily interested in simulating the growing season ozone levels in Class I areas, daily and seasonal cumulative ozone exposure, as characterized by the W126 index, were also evaluated. The daily ozone W126 performance was not as good as the hourly ozone performance; however, the seasonal ozone W126 scaled up from daily values was within 17% of the observations at two typical Class I areas of the SAMI region. The overall ozone performance of the model was deemed acceptable for the purposes of SAMI's assessment.  相似文献   
158.
Aqueous solutions of organophosphorus pesticides were completely mineralized via in-situ generated hydroxyl radicals (HO·) by the Electro-Fenton process. Formation of Fenton's reagent (H2O2, Fe2+) was carried out by simultaneous reduction of O2 and Fe3+ on carbon cathode in acidic medium. The electrochemistry combined with Fenton's reagent provides an excellent way to continuously produce the hydroxyl radical, a powerful oxidant. We demonstrate the efficiency of the Electro-Fenton process to degrade three organophosphorus insecticides: malathion, parathion ethyl and tetra-ethyl-pyrophosphate (TEPP). Degradation kinetics and removals of chemical oxygen demand (COD) have been investigated. Here we show that the mineralization efficiency was over 80% for three organophosphorus pesticides.  相似文献   
159.
The removal of MCPA (4-chloro-2-methyl phenoxyacetic acid) from aqueous solutions by activated spent bleaching earth (SBE) was studied as a function of time, initial concentration, adsorbent concentration, and temperature. The Langmuir and Freundlich isotherms were fitted by the adsorption data obtained. The values of Langmuir and Freundlich constants were determined. The adsorption kinetics was described by the Lagergren equation. Mass transfer coefficient and thermodynamic parameters were also calculated. Column experiments were conducted and brekthrough capacities were found for different concentrations and different flow rates. The study demonstrates that acid-treated SBE could be used as an efficient adsorbent for the removal of MCPA-bearing wastewater effluents.  相似文献   
160.
Yilmaz M  Gül A  Karaköse E 《Chemosphere》2004,56(4):375-380
In this study 96-h LC50 value of cadmium chloride (CdCl2 . H2O), a metal salt widely used in industry, was determined for the guppy (Poecilia reticulata, Pallas, 1859). The experiments were planned in four series of a total of 440 guppies employing the static test method of acute toxicity. 10 fish were placed in each replicate of each dose. The experiments were performed as four replicates, and behavioral changes in the guppy were determined for each cadmium chloride metal salt concentration. The data obtained were statistically evaluated by the use of EPA computer program based on Finney's Probit Analysis Method and a 96-h LC50 value for P. reticulata was found to be 30.4 mg/l in a static bioassay test system. This value was estimated to be 30.6 mg/l with Behrens-Karber's method. The two methods were in good agreement. 95% lower and upper confidence limits for the LC50 were 29.3 and 31.7 mg/l, respectively. The water temperature was kept between 21 and 23 degrees C. The behavioral changes observed in fish were, swimming in imbalanced manner, capsizing, attaching to the surface, difficulty in breathing and gathering around the ventilation filter.  相似文献   
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