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Alcoholic extract of whole fruit of Momordica charantia was prepared. Adult healthy albino rats were divided into four groups and received a dose of 6 mg/l00 gm. body weight of alloxan monohydrate. Animals of group I served as diabetic control group. The animals of II, III, and IV groups received 25 mg, 50 mg and 75 mg doses of the extract respectively for different durations. 75 mg dose showed increase in body weight. All doses of alcoholic extract of M. charantia were able to decrease the blood sugar level significantly. Extract feeding showed definite improvement in the islets of Langerhans. No toxic effect was observed in the liver The significant features of the study have been blood glucose once lowered by the treatment with M. charantia fruit extract remained static even after discontinuation of drug for 15 days. Blood sugar never fell below normal values even with a high dose, in pancreatic islets, beta cells showed definite improvement.  相似文献   
144.
The present investigation deals with fluoride removal from aqueous solution by thermally activated neem (Azadirachta indica) leaves carbon (ANC) and thermally activated kikar (Acacia arabica) leaves carbon (AKC) adsorbents. In this study neem leaves carbon and kikar leaves carbon prepared by heating the leaves at 400 degrees C in electric furnace was found to be useful for the removal of fluoride. The adsorbents of 0.3 mm and 1.0 mm sizes of neem and kikar leaves carbon was prepared by standard sieve. Batch experiments done to see the fluoride removal properties from synthetic solution of 5 ppm to study the influence of pH, adsorbent dose and contact time on adsorption efficiency The optimum pH was found to be 6 for both adsorbents. The optimum dose was found to be 0.5g/100 ml forANC (activated neem leaves carbon) and 0.7g/100 ml forAKC (activated kikar leaves carbon). The optimum time was found to be one hour for both the adsorbent. It was also found that adsorbent size of 0.3 mm was more efficient than the 1.0 mm size. The adsorption process obeyed Freundlich adsorption isotherm. The straight line of log (qe-q) vs time at ambient temperature indicated the validity of langergren equation consequently first order nature of the process involved in the present study. Results indicate that besides intraparticle diffusion there maybe other processes controlling the rate which may be operating simultaneously. All optimized conditions were applied for removal of fluoride from four natural water samples.  相似文献   
145.
The Madagascar Periwinkle, Catharanthus roseus (L.) G. Don (a valued medicinal plant) was exposed to different concentrations ofheavymetals like, CdCl, and PbCl, with a view to observe their bioaccumulation efficiency. Germination was inhibited by both the heavy metals in the seeds previously imbibed in GA, and KNO, for 24 hr. EC50 (the effective concentration which inhibits root length by 50%) was recorded as 180 microM for CdCl2, and 50 microM for PbCl2. Both alpha-amylase and protease activity were reduced substantially on treatment of seeds with increasing concentrations of CdCl2, and PbCl2. Malondialdehyde (MDA) a product of lipoxigenase (LOX) activity also increased due to the treatment of both CdCl, and PbCl2. When two-months-old plants grown in normal soil were transferred to soils containing increasing amounts of these two heavy metals, senescence of lower leaves and extensive chlorosis were noticed after four days of transfer However, plants gradually acclimatized and after 20 days the chlorophyll content was almost comparable to normal. Plants receiving CdCl2 treatment (250 microg g(-1) and less) became acclimatized after two weeks and started normal growth. But PbCl2 of 432 microg g(-1) and less could not affect the plant growth throughout, after a preliminary shock was erased. In case of CdCl2 treatment, a stunted growth with reduced leaf area, reduced biomass and sterility were recorded after six months, while plants show normal growth and flowering in case of PbCl2 treatment. Total alkaloid was also found to be decreased in the roots of CdCl2 treated plants. No change was observed in case of PbCl2. GA3 treatments to the CdCl2 treated plants show internode elongation and increase in leaf area with relatively elongated leaves and thinning of stem diameter AAS analyses of leaves of treated plants exhibited 5-10% accumulation of cadmium, but there was no accumulation of lead at all.  相似文献   
146.
There has been considerable research on North–South issues on climate change; however, little work has been done on how the recent discovery of oil in some developing countries could affect North–South relations, the prospects for development for the South, climate change and local socio-environmental issues. Using the theory of inclusive development, the concept of the Right to Development, and their relation to stranded assets, this paper addresses the question: what does inclusive development imply at the national and global level in dealing with oil extraction in the context of climate change? Based on a literature review and a layered case study of Kenya, this paper concludes that (a) Kenyans argue that Kenya has a right to extract and use oil resources and that rich countries should reduce their extraction and use; (b) such a claim could be integrated in an appropriate emissions trading scheme; and that (c) Kenya should also account for the national and local socioecological aspects to reduce potential local conflict, yet the conditions favoring inclusive development are not yet established. However, such an argument may also lead to perverse results. If addressing climate change requires phasing out fossil fuels, this argument may lead to stranded assets in both developed and developing countries, and may ironically leave developing countries poorer off as stranded assets are possibly more expensive than having stranded resources.  相似文献   
147.
Emission from field burning of agricultural crop residue is a common environmental hazard observed in northern India. It has a significant potential health risk for the rural population due to respirable suspended particulate matter (RSPM). A study on eight stage size segregated mass distribution of RSPM was done for 2 wheat and 3 rice crop seasons. The study was undertaken at rural and agricultural sites of Patiala (India) where the RSPM levels remained close to the National Ambient Air quality standards (NAAQS). Fine particulate matter (PM(2.5)) contributed almost 55% to 64% of the RSPM, showing that, in general, the smaller particles dominated during the whole study period with more contribution during the rice crop as compared to that of wheat crop residue burning. Fine particulate matter content in the total RSPM increased with decrease in temperature. Concentration levels of PM(10) and PM(2.5) were higher during the winter months as compared to that in the summer months. Background concentration levels of PM(10), PM(2.5) and PM(10-2.5) were found to be around 97 ± 21, 57 ± 15 and 40 ± 6 μg m(-3), respectively. The levels increased up to 66, 78 and 71% during rice season and 51, 43 and 61% during wheat crop residue burning, respectively. Extensive statistical analysis of the data was done by using pair t-test. Overall results show that the concentration levels of different size particulate matter are greatly affected by agricultural crop residue burning but the total distribution of the particulate matter remains almost constant.  相似文献   
148.
• Eco-friendly IONPs were synthesized through solvothermal method. • IONPs show very high removal efficiency for CeO2 NPs i.e. 688 mg/g. • Removal was >90% in all synthetic and real water samples. • >80% recovery of CeO2 NPs through sonication confirms reusability of IONPs. Increasing applications of metal oxide nanoparticles and their release in the natural environment is a serious concern due to their toxic nature. Therefore, it is essential to have eco-friendly solutions for the remediation of toxic metal oxides in an aqueous environment. In the present study, eco-friendly Iron Oxide Nanoparticles (IONPs) are synthesized using solvothermal technique and successfully characterized using scanning and transmission electron microscopy (SEM and TEM respectively) and powder X-Ray diffraction (PXRD). These IONPs were further utilized for the remediation of toxic metal oxide nanoparticle, i.e., CeO2. Sorption experiments were also performed in complex aqueous solutions and real water samples to check its applicability in the natural environment. Reusability study was performed to show cost-effectiveness. Results show that these 200 nm-sized spherical IONPs, as revealed by SEM and TEM analysis, were magnetite (Fe3O4) and contained short-range crystallinity as confirmed from XRD spectra. Sorption experiments show that the composite follows the pseudo-second-order kinetic model. Further R2>0.99 for Langmuir sorption isotherm suggests chemisorption as probable removal mechanism with monolayer sorption of CeO2 NPs on IONP. More than 80% recovery of adsorbed CeO2 NPs through ultrasonication and magnetic separation of reaction precipitate confirms reusability of IONPs. Obtained removal % of CeO2 in various synthetic and real water samples was>90% signifying that IONPs are candidate adsorbent for the removal and recovery of toxic metal oxide nanoparticles from contaminated environmental water samples.  相似文献   
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Karanja oil, containing 6.2% free fatty acids (FFAs), was considered for biodiesel production using a single-step solid-phase acid catalyzed process. Different types of zeolites and Amberlyst15 catalysts were tested and biodiesel was produced. Under similar conditions, the highest biodiesel yield was achieved using an Amberlyst15 catalyst, which contained 3–5% of moisture. The effects of operating parameters of the reaction such as reaction temperature, catalyst amount, and methanol-to-oil ratio were studied. An increase of methanol:oil ratio revealed a non-monotonic increase in biodiesel yields. Similar non-monotonic behavior was observed when Jatropha oil was used. Leaching and catalyst reusability were also considered. No significant effects of leaching were observed and catalyst reusability appeared to be affected by methanol interactions. The presence of a co-solvent, Tetrahydrofuran (THF), increased the biodiesel yield. Furthermore, an optimum amount of THF (THF:methanol volume ratio of 1:2) gave rise to the highest biodiesel yield. A biodiesel yield of 93% was achieved at 120 °C using a single-step process with Amberlyst15 as a catalyst, THF as a co-solvent, and a methanol:oil ratio of 30:1.  相似文献   
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