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41.
Environmental Science and Pollution Research - In the present study, fermentative production of bacterial nanocellulose (BNC) by using Komagataeibacter xylinus strain SGP8 and characterization of...  相似文献   
42.
In a field study carried out at three different locations, the dissipation of spiromesifen on cotton and chili was studied and its DT50, and DT99 were estimated at each location. Spiromesifen was sprayed on chili at 96 and 192 g a.i. ha−1 and cotton at 120 and 240 g a.i. ha−1. Samples of chili fruits were drawn at 0, 1, 3, 5, 7, 10, 15, 21, 30 days after treatment and that of cotton seed and lint at first picking and harvest. Soil samples were drawn 30 days after treatment from 0 to 15 and 15 to 30 cm layer. Quantification of residues was done on GC–MS in Selected Ion Monitoring (SIM) mode in mass range 271–274 m/z. The LOQ of this method was found 0.033 μg g−1, LOD being 0.01 μg g−1. The DT50 of spiromesifen when applied at recommended doses in chili fruits was found to be 2.18–2.40 days. Ninety-nine percent degradation was found to occur within 14.5–16.3 days after application. Residues of spiromesifen were not detected in cotton seed and lint samples at the first picking. In soil, no residues of spiromesifen were detectable 15 days after treatment.  相似文献   
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44.
The objective of the present study was to synthesize and evaluate the effect of change in concentration of chitosan (CS) and N,N-methylenebisacrylamide (MBA)- a cross linking agent, on various properties such as lower critical solution temperature (LCST), zeta potential, particle size and poly dispersity index (PDI) of the synthesized co-polymer. Nine different formulations of chitosan-g-poly (N-isopropylacrylamide) (CS-g-PNIPAAm) co-polymer with varying CS and MBA concentrations were synthesized by a surfactant free dispersion copolymerization method. The synthesized co-polymer was further characterized and confirmed for its structure, morphology, particle size, zeta-potential, thermo and pH responsive properties, in-vitro cyto-compatability and stability studies using various analytical tools. The data confirms the successful synthesis of co-polymer. The increase in the concentrations of CS and MBA during the polymerization of co-polymer, resulted in proportional increase of LCST and zeta potential with decrease in particle size of co-polymeric nanoparticles. pH responsive studies showed that as the pH of the medium increases particle size and zeta potential decreases with increase in LCST of co-polymeric nanoparticles. From the results, it can be inferred that the synthesized co-polymeric nanoparticles exerted thermo and pH responsive properties with biocompatibility. By varying the CS and MBA concentrations in the co-polymer, desired LCST, particle size and zeta potential for co-polymeric nanoparticles can be obtained and thus the synthesized co-polymer may have great potential to be used as a drug carrier (nanoform) with both thermo and pH responsiveness.  相似文献   
45.
Heterobimetallic complexes of the type Ni[Cu(SCN)2]2 · L (where L = acetophenone benzoylhydrazone, acetophenone isonicotinoyl hydrazone, acetophenone salicyloylhydrazone (ash), acetophenone anthraniloylhydrazone, p-hydroxy acetophenone benzoylhydrazone, p-hydroxy acetophenone isonicotinoyl hydrazone p-hydroxy acetophenone salicyloylhydrazone (phash), p-hydroxy acetophenone anthraniloyl hydrazone), were synthesized and characterized. The complexes are polymeric, insoluble in common organic solvents and are nonelectrolytes. Magnetic moments and electronic spectral studies suggest a spin-free octahedral geometry for the complexes. IR spectra show the bidentate nature of all the ligands bonding through >C=O and >C=N–groups. The SCN group acts as a bridge between two metal centers. X-ray powder diffraction parameters for Ni[Cu(SCN)2]2 · ash and Ni[Cu(SCN)2]2 · phash correspond to orthorhombic and tetrahedral crystal lattices, respectively, for these complexes. The complexes show a significant antifungal activity against Rizoctonia, Stemphylium and Aspergillus sp. and antibacterial activity against Clostridium and Pseudomonas sp. The metal complexes are more active than the ligands.  相似文献   
46.
The aim of this study was to assess the toxicity reduction of wastewaster after treatment with fly ash. Fly ash is a waste material which is formed as a result of coal burning in power plants, but has the potential to adsorb heavy metal ions. The present study examined the adsorption capacity of fly ash to adsorb Pb2+, Cu2+, and Zn2+ from waste water under different conditions of contact time, pH, and temperature. Uptake of metal ions by fly ash generally rose with increasing pH. At lower temperatures the uptake of heavy metal adsorption were enhanced. Significant reduction in Pb2+ (79%), Cu2+ (53%), and Zn2+ (80%) content was found after treatment with fly ash of waste water treatment. Using the microtox test toxicity of the effluent was reduced by 75% due to removal of Pb2+ ion by the fly ash. Data indicated that fly ash generated by power plants may be used beneficially to remove metals from waste water.  相似文献   
47.
Particulate matter concentrations were measured in an industrial region in the Ganjam district of Odisha. The average levels of suspended particulate matter (SPM) were measured to be 142 ± 8 and PM10 of particulate matter with a size of less than 10 micrometers (PM10) to be 50 ± 15 μg m?3. Out of the 14 elements determined, Ca, Na, Mg, Fe, and K contributed more than 95% of the total weight. In enrichment factors, the trace elements, i.e., Zn, Pb, Cd, and Hg were observed to be highly enriched in the SPM and PM10. Factor analysis indicates that more than 75% of the variance was due to five component factors, which have eigenvalues greater than 1. Intake of elements through inhalation route to adults has been estimated.  相似文献   
48.
In India, the traditional methods are used for urban solid waste management. These practices are associated with degradation of the urban environment Hence, an environmentally sound garbage management system is required for the urban waste management. The concept of waste minimization needs to be adopted in such systems. It is possible to implement certain corrective measures at collection, storage, transport and disposal of urban solid waste to minimize the adverse impacts on the environment The present investigations are emphasized on generation, characterzation and ecofriendly disposal of solid waste generated in Jalgaon city, Maharashtra. In the present study the waste generation at source was studied in the various income groups of the city. The per capita waste generation was studied by sampling the waste directly from the source of generation. The study reveals that the waste generation is large in the high-income group followed by middle and low-income group public. Further the physicochemical characterization of the waste was also studied. The data generated will help to develop environmentally sound and economically feasible solid waste management system for Ihe city.  相似文献   
49.
The relative sensitivity of tannery effluent before and after treatment was compared by employing Nostoc muscorum and microtox assay in laboratory. The effect on chlorophyll, protein and biomass content of Nostoc muscorum was studied with the luminescent property inhibition of Photobacterium phosphorium and compared with algal bioassay. The results of microtox assay after 5, 15 and 30 min of exposure were compared with data obtained from algal bioassay. It was observed that the luminescent property of Photobacterium phosphorium in microtox assay as well as the chlorophyll content of Nostoc muscorum in algal assay were the most sensitive parameters in toxicity evaluation of tannery effluent. The microtox assay produced notably comparable EC50 values with that of algal bioassay. The microtox assay of toxicity showed that EC50 (%) in 30 min was 3.19 and 63.49 for untreated and treated tannery effluent, respectively while in algal bioassay the EC50 for chlorophyll was in between 0-2.5% and 100%, respectively, in untreated and treated effluent. More than 60% reduction of toxicity was noted in treated tannery effluent in both test system.  相似文献   
50.
Effects of salicylic acid (SA) on seed germination, seedling growth, flowering and biochemical activities were studied out in four cowpea (Vigna unguiculata) genotypes in control environments. The results revealed that both germination and seedling growth were negatively affected by 0.02%. SA application, however did not affect the size of full expanded buds, time of 50% flowering and date of flower initiation. A maximum increase in peroxidase (EC1.11.1.7) activity was observed in UPC 4200 over other genotypes. No significant change in the content of total soluble and intercellular fluid proteins was observed except in UPC 4200 genotype. SA induced accumulation of total soluble sugars more at flowering stage than at seed setting stage. It is evident from the present study that UPC 4200 genotype was more responsive to salicylic acid both in terms of increased peroxidase activity and less negative effect on morphological attributes, thus suggesting its wider use without negative impact on environment as salicylic acid has been reported in plants.  相似文献   
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