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41.
Environmental Science and Pollution Research - Over the years, biodegradation has been an effective technique for waste water treatment; however, it has its own limitations. In order to achieve a...  相似文献   
42.
The present investigation was undertaken to assess the effects of sublethal concentrations of zinc (0.1 and 0.2 mgl(-1)) on the nutritional value of fish Channa punctatus after exposure for 135 days. The parameters studied were, levels of total proteins, glycogen, total lipids, cholesterol and vitamins (A and D) in the muscle. Total proteins, glycogen, total lipids and vitamin D show highly significant decline from day 90 to 135, while cholesterol and vitamin A, show no significant changes upto 105 days. This study signifies a drastic reduction in the nutritive value of fish, which is compounded by the fact that under natural conditions fish are exposed to these levels of zinc for prolonged periods.  相似文献   
43.
Effect of cumulative doses of estradiol -17beta (E2-7, 14 and 28 mg/kg body weight) and 17alpha, 20beta-dihydroxy-4-pregnen-3-one (17alpha,20betaP-7, 14 and 28 mg/kg body weight) on total phospholipids (TP) and various phospholipids- phosphatidylcholine (PC), phosphatidylserine (PS), phosphatidylinositol (PI) and phosphatidylethanolamine (PE) on liver plasma and ovary were investigated during the reproductively active preparatory and prespawning phases of the annual reproductive cycle in the freshwater female catfish, H. fossilis. The effect of E2 on TP was generally stimulatory and has pronounced effect than 17alpha,20betaP during both the phases. The levels of PC was promoted high during prespawning phase by E2 comparatively very less than by 17alpha, 20betaP in studied tissues during both the phases. The levels of PS after E2 treatments was maximum in all tissues during prespawning phase whereas 17alpha,20betaP was effective only in liver during this phase. The PI was elevated in liver during preparatory phase but its elevation was in all studied tissues during prespawning phase after E2 treatments. The levels of PI was most effective in ovary during preparatory phase in response to 17alpha,20betaP. The levels of PE was declined in liver but elevated in ovary after E2 treatments during both the phases. Treatments of E2 during preparatory phase showed greater number of vitellogenic oocytes as compared to 17alpha,20betaP treatments. The present finding has demonstrated that estradiol-17beta has more pronounced effects than the 17alpha,20beta P in regulation of different phospholipids and ovarian recrudescence during reproductively active phases and among the phospholipids the PC is the main phospholipids of vitellogenin/ovarian lipids in H. fossilis.  相似文献   
44.
The impact of distillery effluent in various concentrations (1, 2.5, 5, 10, 25, 50, 75 and 100%) on the seed germination, Speed of Germination Index, growth behaviour, leaf area, biomass, net primary productivity, pigment content, reproductive capacity, seed output, seed weight, seed density and the seed protein content of Cicer arietinum L. plants was investigated. The percentage and speed of germination of seeds were increasingly retarded with increase in effluent concentration and at 100% concentration there was no germination. The seedlings exhibited maximum shoot length at 5% concentration and maximum root length at 2.5% concentration. The values of root and shoot lengths, leaf area, biomass, net primary productivity, pigment content, reproductive capacity, seed output, seed weight, seed density and seed protein content in pot plants exhibited a gradual increase from the control up to 5% concentration and decreases at higher concentrations. The very high BOD load and the presence of excessive concentrations of soluble salts could be responsible for the toxicity of the effluent. The effluent at up to 5% concentration was, however, beneficial for the overall growth parameters studied and can thus be used as a liquid fertilizer.  相似文献   
45.
The mass concentration of carbonaceous species, organic carbon (OC), and elemental carbon (EC) using a semicontinuous thermo-optical EC-OC analyzer, and black carbon (BC) using an Aethalometer were measured simultaneously at an urban mega city Delhi in Ganga basin from January 2011 to May 2012. The concentrations of OC, EC, and BC exhibit seasonal variability, and their concentrations were ~2 times higher during winter (OC 38.1?±?17.9 μg m?3, EC 15.8?±?7.3 μg m?3, and BC 10.1?±?5.3 μg m?3) compared to those in summer (OC 14.1?±?4.3 μg m?3, EC 7.5?±?1.5 μg m?3, and BC 4.9?±?1.5 μg m?3). A significant correlation between OC and EC (R?=?0.95, n?=?232) indicate their common emission sources with relatively lower OC/EC ratio (range 1.0–3.6, mean 2.2?±?0.5) suggests fossil fuel emission as a major source of carbonaceous aerosols over the station. On average, mass concentration of EC was found to be ~38 % higher than BC during the study period. The measured absorption coefficient (babs) was significantly correlated with EC, suggesting EC as a major absorbing species in ambient aerosols at Delhi. Furthermore, the estimated mass absorption efficiency (σabs) values are similar during winter (5.0?±?1.5 m2 g?1) and summer (4.8?±?2.8 m2 g?1). Significantly high aerosol loading of carbonaceous species emphasize an urgent need to focus on air quality management and proper impact assessment on health perspective in these regions.  相似文献   
46.
47.
The distribution of Nickel-63, Iron-59, Manganese-54 and Tin-113 in plasma was studied in rats which received single intravenous (i.v.) injection of aqueous solutions of their salts alone, and in rats which also received single intramuscular (im) injection of triethylene tetramine (TETA). TETA was extremely effective in reducing the plasma concentration of Nickel-63 followed by that of Iron-59, Manganese-54 and Tin-113.  相似文献   
48.
Present investigation deals with the utilisation of bagasse fly ash (BFA) (generated as a waste material from bagasse fired boilers) and the use of activated carbons-commercial grade (ACC) and laboratory grade (ACL), as adsorbents for the removal of congo red (CR) from aqueous solutions. Batch studies were conducted to evaluate the adsorption capacity of BFA, ACC and ACL and the effects of initial pH (pH(0)), contact time and initial dye concentration on adsorption. The pH(0) of the dye solution strongly affected the chemistry of both the dye molecules and BFA in an aqueous solution. The effective pH(0) was 7.0 for adsorption on BFA. Kinetic studies showed that the adsorption of CR on all the adsorbents was a gradual process. Equilibrium reached in about 4h contact time. Optimum BFA, ACC and ACL dosages were found to be 1, 20 and 2 g l(-1), respectively. CR uptake by the adsorbents followed pseudo-second-order kinetics. Equilibrium isotherms for the adsorption of CR on BFA, ACC and ACL were analysed by the Freundlich, Langmuir, Redlich-Peterson, and Temkin isotherm equations. Error analysis showed that the R-P isotherm best-fits the CR adsorption isotherm data on all adsorbents. The Freundlich isotherm also shows comparable fit. Thermodynamics showed that the adsorption of CR on BFA was most favourable in comparison to activated carbons.  相似文献   
49.
Selective catalytic reduction (SCR) technology increasingly is being applied for controlling emissions of nitrogen oxides (NOx) from coal-fired boilers. Some recent field and pilot studies suggest that the operation of SCR could affect the chemical form of mercury (Hg) in coal combustion flue gases. The speciation of Hg is an important factor influencing the control and environmental fate of Hg emissions from coal combustion. The vanadium and titanium oxides, used commonly in the vanadia-titania SCR catalyst for catalytic NOx reduction, promote the formation of oxidized mercury (Hg2+). The work reported in this paper focuses on the impact of SCR on elemental mercury (Hg0) oxidation. Bench-scale experiments were conducted to investigate Hg0 oxidation in the presence of simulated coal combustion flue gases and under SCR reaction conditions. Flue gas mixtures with different concentrations of hydrogen chloride (HCl) and sulfur dioxide (SO2) for simulating the combustion of bituminous coals and subbituminous coals were tested in these experiments. The effects of HCl and SO2 in the flue gases on Hg0 oxidation under SCR reaction conditions were studied. It was observed that HCl is the most critical flue gas component that causes conversion of Hg0 to Hg2+ under SCR reaction conditions. The importance of HCl for Hg0 oxidation found in the present study provides the scientific basis for the apparent coal-type dependence observed for Hg0 oxidation occurring across the SCR reactors in the field.  相似文献   
50.
Antifungal activity (reduction in colony diameter) of various extracts (pt. ether, chloroform, ethyl acetate, ethyl alcohol and aqueous) of aerial and root parts of Boerhavia diffusa (Nictaginaceae) was screened against dermatophytic fungi Microsporum fulvum. Statistically significant increase has been recorded in the % inhibition of the target fungal species with increasing test concentrations (1000-5000 ppm) of chloroform, ethyl acetate and ethyl alcohol extracts of the root. The maximum % inhibition observed in various solvent extracts of root was about 26% (chloroform), 46% (ethyl alcohol) and 57% (ethyl acetate) at 5000 ppm concentration with time exposure of 10 days. The colony diameter of the target mycelial colony decreased with increasing supplementation of the phytoextract, showing the presence of significant amount of some antifungal phytochemical moiety.  相似文献   
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