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21.
In the present investigation, hepatotoxic effect of a commercially available insecticide formulation of dicofol (Colonel–S® 18.5% emulsified concentrate) was studied in the developing chick embryo. Fertilized eggs of Gallus domesticus were immersed in three different dose concentrations, i.e. 250, 500, and 1000 mg L?1 of Colonel–S on “0” and fourth days of incubation for 60 min at 37 °C and incubated till embryonic day 16. Severe histopathological cellular lesions, such as extensive cell degeneration and necrosis with enlarged blood sinusoids, cytoplasmic vacuolization, and leucocyte infiltrations with congestion or dilation of central vein, appeared in dose-depended manner. Dicofol treatment also caused significant decrease in the levels of total protein, glycogen, and glutathione content and an increase in alkaline phosphatase activity of embryonic liver, whereas glutamic pyruvic transaminase activity showed mixed response.  相似文献   
22.
In India, groundwater assessment units are classified as overexploited areas, critical areas, semi-critical, or safe areas based on the stage of groundwater development and long-term water level trends. Intuitively, in the safe units, wells are expected to function and have good yields. Besides, in the safe units, new wells are expected to be successful. Conversely, the expectation of a successful well or wells with good yields is much lesser in the overexploited units. However, when these expectations are not met in the field, doubts are raised about the quality of assessment and its usefulness, and there is outright distrust on the agencies assessing groundwater resource by the common man as well as on the planners, administrators, and the politicians. Therefore, there is a need to present the results in a way that does not create confusion. One of the methods is to combine the assessment results with aquifer characters using geographic information system (GIS); when this is done, a whole set of newer classes emerge, which can be mapped. These classes are termed as groundwater typologies in this study. Each typology has some characteristics or traits in common, which include basic aquifer character as well as the stage of groundwater development. Thus, a class may be safe, but if the aquifer is poor, then it is separated from a class that is safe and where the aquifer is good and so on. In Andhra Pradesh, which is taken as the case study for this purpose, eight main typologies emerged, and two of these main typologies were further divided into four subtypologies each. This new way of understanding the pattern of groundwater abstraction (using GIS) has a better visual impact. Groundwater typologies are found to be much more rational and useful in developing management strategies, rather than simple listing as overexploited areas, critical areas, semi-critical areas, and safe areas as is commonly done. The typologies so delineated indicate on the map (or table) that balanced usable groundwater is in between 5 and 6 bcm/a as against the estimated balance of 20.5 bcm/a, and it is largely in poor hard rock type of aquifers, which occupy about a third of the area of the state.  相似文献   
23.
Decolorization of synthetic dyes using a copper complex with glucaric acid   总被引:1,自引:0,他引:1  
Selected azo, acridine, triphenyl methane, anthraquinone and thiazine-based dyes were decolorized using a catalytic system consisting of Cu(II)/glucaric acid/H(2)O(2). More than 90% decolorization was obtained with 100 ppm Acridine Orange, Azure B, Chicago Sky Blue, Crystal Violet, Methyl Orange, Poly B-411, Reactive Black 5, Reactive Blue 2, and Remazol Brilliant Blue R within 24 h. Seventy to eighty percent decolorization was achieved within the first 6 h. The decolorizaton was not affected by pH. The involvement of hydroxyl radicals produced in the system in the decolorization of the dye molecules was confirmed by electron spin resonance study.  相似文献   
24.
The current study evaluates the cytogenetic effects of chromium (III) oxide nanoparticles on the root cells of Allium cepa. The root tip cells of A. cepa were treated with the aqueous dispersions of Cr2O3 nanoparticles (NPs) at five different concentrations (0.01, 0.1, 1, 10, and 100 μg/mL) for 4 hr. The colloidal stability of the nanoparticle suspensions during the exposure period were ascertained by particle size analyses. After 4 hr exposure to Cr2O3 NPs, a significant decrease in mitotic index (MI) from 35.56% (Control) to 35.26% (0.01 μg/mL), 34.64% (0.1 μg/mL), 32.73% (1 μg/mL), 29.6% (10 μg/mL) and 20.92% (100 μg/mL) was noted. The optical, fluorescence and confocal laser scanning microscopic analyses demonstrated specific chromosomal aberrations such as—chromosome stickiness, chromosome breaks, laggard chromosome, clumped chromosome, multipolar phases, nuclear notch, and nuclear bud at different exposure concentrations. The concentration-dependent internalization/bio-uptake of Cr2O3 NPs may have contributed to the enhanced production of anti oxidant enzyme, superoxide dismutase to counteract the oxidative stress, which in turn resulted in observed chromosomal aberrations and cytogenetic effects. These results suggest that A. cepa root tip assay can be successfully applied for evaluating environmental risk of Cr2O3 NPs over a wide range of concentrations.  相似文献   
25.
Occupational exposure is unregulated in developing countries like India, and becoming the most common cause of disease of environmental origin. The present study was aimed to investigate the effects of occupational exposure on plasma lipid profiles, and risk of cardiovascular diseases. A total of 79 human volunteers were included in the study. Control subjects were healthy housewives of Karimnagar, India. Occupationally exposed individuals included different occupational workers like petrol station attendants, battery chargers, drivers, welders, pesticide-exposed workers, painters, and auto mechanics. These subjects were shown to be chronic occupationally-exposed for at least three years, and neither associated with any other chronic pathological conditions like hypertension or diabetes, nor under any medication other than analgesics during the month preceding the study. Subjects with excessive high or low caloric intake were excluded from the study. Total cholesterol (TC), LDL cholesterol, triglycerides (TG), VLDL cholesterol, LDL/HDL cholesterol, and TC/HDL ratio in these subjects were significantly higher than those in control subjects, whereas HDL cholesterol was not markedly affected. Blood pressure (systolic and diastolic), and other anthropometric parameters (body mass index (BMI), body fat index (BFI), body surface area (BSA)) were not significantly different between groups. Data suggest that chronic occupational exposure increases plasma lipid levels and is thereby associated with cardiovascular complications.  相似文献   
26.
This paper describes the development and application of the Visibility and Haze in the Western Atmosphere (VISHWA) model to understand the source-receptor relationships that govern chemical species relevant to visibility degradation in the western United States. The model was developed as part of a project referred to as Visibility Assessment for Regional Emission Distributions (VARED), the objective of which is to estimate the contributions of various geographical regions, compounds, and emission

sources to light scattering and absorption by particles on the Colorado Plateau.

The VISHWA model is a modified version of a comprehensive Eulerian model, known as the Acid Deposition and Oxidant Model.1 The modifications were designed to obtain the computational efficiency required to simulate a one-year period at about 1/25th of real time, and at the same time incorporate mechanistic features relevant to realistic modeling of the fate and transport of visibility degrading species. The modifications included use of a condensed chemical mechanism; incorporation of reactions to simulate the formation of secondary organic particles; and use of a semi-Lagrangian advection scheme to preserve concentration peaks during advection.

The model was evaluated with 1992 air quality data from Project MOHAVE (Measurements of Haze and Visual Effects) intensive experiments. An important conclusion of this evaluation is that aqueous-phase oxidation of SO2 to sulfate in nonprecipitating clouds makes a significant contribution to observed sulfate levels during winter as well as summer. Model estimates of ambient sulfate

for the winter intensive were within a factor of 2 of the observations for 75% of the values. The corresponding statistic for the summer intensive was 90%. Model estimates of carbon were within a factor of 2 of the limited set of observations.  相似文献   
27.
Economic and population growth in Asia over the last three decades has been unprecedented. While conventional economic indicators have been increasing consistently, indicators of resource and environmental quality have been deteriorating, raising questions about the implications of future growth. Economic growth in the future is considered to be contingent on ensuring a more efficient use of natural resources, while simultaneously striving to reduce environmental impacts. We examine time trends of three efficiency indicators; agricultural efficiency, energy efficiency of economic production and carbon efficiency of energy use, for the five most populous countries in Asia in order to assess whether industrial development has lead to increased resource use efficiency and an associated reduction in total resource use and environmental impacts. Our results indicate that agricultural efficiency has decreased in all five countries. Results are mixed for energy and carbon efficiencies. Where increases in energy and carbon efficiency have occurred, they have been completely overwhelmed by absolute increases in energy use and carbon emissions caused by increases in the scale of economic activity. Based on this analysis, we study the potential for further improvements and policy implications for future food supply, energy consumption and carbon emissions in the region.  相似文献   
28.
IntroductionPollution of natural waters with waste effluentsarising from various industries has become a seriousproblem in India.In Rajasthan particularly,textilemills represent an important economic sector.Effluents from these textile and other dye-relat…  相似文献   
29.
Abstract

Catalyst recovery studies were conducted for gasified chars produced from steam gasification of Illinois #6 coal catalyzed with two different catalyst systems. A ternary (43.5 mol% Li2 CO3 –31.5 mol% Na2 CO3 –25 mol% K2 CO3 ) and a binary (29 mol% Na2 CO3 –71 mol% K2 CO3 ) eutectic catalyst system were used for gasifying coal. Various extraction schemes, such as water extraction, H2 SO4 extraction, and acetic acid extraction, were evaluated with respect to their extraction efficiencies. Effects of major process variables, such as solvent-to-char ratio, mixing time, temperature, and concentration, on the extraction efficiency were evaluated. A process schematic for the entire catalyst recovery, regeneration, and recycle scheme was developed and the preliminary process economics were determined based on these extraction schemes. H2 SO4 extraction was found to be the most desirable. It also turned out to be more attractive than a once-through throwaway system.  相似文献   
30.
Anionic surfactant (AS) concentrations in wet up-flow anaerobic sludge blanket reactor (UASBR) sludges from five sewage treatment plants (STPs) were found to range from 4480 to 9233mgkg(-1)drywt. (average 7347mgkg(-1)drywt.) over a period of 18 months. After drying on sand drying beds (SDBs), AS in dried-stabilized sludges averaged 1452mgkg(-1)drywt., a reduction of around 80%. The kinetics of drying followed simple first-order reduction of moisture with value of drying constant (k(d))=0.051d(-1). Reduction of AS also followed first-order kinetics. AS degradation rate constant (k(AS)) was found to be 0.034d(-1) and half-life of AS as 20 days. The order of rates of removal observed was k(d)>k(AS)>k(COD)>k(OM) (drying >AS degradation>COD reduction>organic matter reduction). For the three applications of dried-stabilized sludges (soil, agricultural soil, grassland), values of risk quotient (RQ) were found to be <1, indicating no risk.  相似文献   
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