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151.
Pulp paper mill pollutants are the major source of aquatic contamination having metals, lignin and chlorophenols. Study was conducted to see the effect of these contaminants on antibiotic resistance pattern of isolated bacteria. Pulp paper effluents were evaluated for its physico-chemical properties i.e, BOD 72143 +/- 164.81 to 22.32 +/- 2.48, COD 213136 +/- 583.59 to 60.40 +/- 6.34, total phenol 386 +/- 71.24 to 0.43 +/- 0.0, lignin 26312 +/- 258.59 to 73.67 +/- 31.81and microbial quality i.e. K. pneumonae, S. typhi, S. faecalis, P. aeruginosa, E. coli, Ent. faecalis, A. hydrophila, B. subtilis, S. aureus, Y enterolitica and V vulrificus. Antibiotic sensitivity (10-30 microg), heavy metal resistance (100-1000 microg ml(-1)), lignin (1000-10,000 ppm) and pentachlorophenol (100-1000 ppm) tolerance of bacterial strains were assessed by seven classes of antibiotics. Eleven bacterial isolates were found multidrug resistant towards antibiotics, heavy metal, lignin and PCP. Out of 11 isolates, 90.9% were found resistant against eleven antibiotics which acquired 100% resistant in presence of heavy metal, lignin and chlorophenols. Results also revealed that concentration of lignin (50-350 ppm) and PCP (5-30 ppm) induced maximum growth (273-8050 cfu ml(-1)) of pathogenic bacteria in river water.  相似文献   
152.

This work describes the design of novel Cu(II) complexes and their application in the photocatalytic degradation of methylene blue (MB). The same photocatalyst exhibits antibacterial activity against Escherichia coli (gram-negative) and Bacillus circulans (gram-positive). The characterisation of the photocatalysts has been done by several up-to-date physical methods. The rationale behind the photocatalysts’ beneficial intervention is discussed in this study. Statistical analysis of the degradation of MB is done using a one-way ANOVA, and the significance of means is determined by a multiple comparison test using Turkey HSD. Also, the degradation of MB follows pseudo first-order kinetics with high correlation coefficient values (R2?>?0.95), making them useful as simple and low-cost organic dye degradation agents.

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153.
This study reports on the biocultural dimensions of the tasat (Arenga obtusifolia Griff.) tree and its conservation by various informal institutions of the Adi tribe of Arunachal Pradesh, India. The study included 240 Adi community members (120 men and 120 women) residing in 12 villages of the East Siang and Upper Siang districts of Arunachal Pradesh. The study was conducted using personal interviews and participatory methods. Results indicated that the stem of tasat is used as a traditional food during droughts and in preparing an ethnic beverage. Tasat is being conserved by the Adi tribe in various habitats. Plant populations of tasat were observed relatively higher in Upper Siang than the East Siang district. The study found differences in the status of biocultural knowledge between genders and different age groups. Kebang and reglep are two indigenous institutions of men and women, respectively, and play leading roles in sustaining tasat plants in various habitats. Women of the Upper Siang district still maintain a knowledge network for diffusing biocultural knowledge related to tasat, among others, through a barter system. Changing land use patterns in agriculture affects tasat conservation. The value addition for tasat based products, and rewarding women who conserve tasat, can enhance the sustainability of tasat based on biocultural knowledge and institutions.  相似文献   
154.
ABSTRACT: A 2.2-hectare potato (Solanum tuberosum L. cv Chieftain) field at Saint Leonard d'Aston, Quebec (lat. 72° 24′ 30″ long. 46° 5′ 30″) was instrumented to measure tile drain flow over two growing seasons, 1989 and 1990. The soil was a Sainte Jude sandy loam. Soil properties and nitrate concentrations in the drain flow were measured. The CREAMS (Chemicals, Runoff and rosion from agricultural Management systems) computer simulation model was validated for the study site. CREAMS underpredicted event percolation depths. However, total monthly percolation depths were close to observed values. CREAMS overpredicted event nitrate concentrations leached to tile drainage. There was a poor match between predicted and observed event nitrate concentrations in drain flow (coefficient of predictability, CPA= 104.95). Based on a sensitivity analysis, input parameters, representative of local conditions, were determined for the CREAMS hydrology and nutrient submodels.  相似文献   
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Manure is an impending source of carbon(C), sulfur(S) and water(H_2 O). Consequently,microbial populations utilize these constituents to produce methane(CH4), carbon dioxide(CO_2), greenhouse gases(GHGs), and hydrogen sulfide(H_2 S). Application of nanoparticles(NPs) to stored manure is an emerging GHG mitigation technique. In this study, two NPs: nano zinc oxide(nZnO) and nano silver(nAg) were tested in swine manure stored under anaerobic conditions to determine their effectiveness in mitigating gaseous emissions and total gas production. The biological sources of gas production, i.e., microbial populations were characterized via Quantitative Polymerase Chain Reaction(qPCR) analysis. Additionally, pH, redox, and VFAs were determined using standard methods. Each treatment of the experiment was replicated three times and NPs were applied at a dose of 3 g/L of manure. Also, headspace gas from all treatment replicates were analyzed for CH_4 and CO_2 gas concentrations using an SRI-8610 Gas Chromatograph and H_2 S concentrations were measured using a Jerome 631 X meter. Nanoparticles tested in this study reduced the cumulative gas volume by 16%–79% compared to the control. Among the NPs tested, only nZnO consistently reduced GHG concentrations by 37%–97%. Reductions in H_2 S concentrations ranged from 87% to97%. Gaseous reductions were likely due to decreases in the activity and numbers of specific gas producing methanogenic archaea and sulfate reducing bacterial(SRB)species.  相似文献   
157.
The effect of pH, nutrient and aeration was studied on the removal of colour and reduction of BOD, COD and heavy metals with addition of readily available source of nitrogen and phosphorus in concentration of 1.0 g/L. Recalcitrant compound was effectively degraded by active microbial consortia. The isolated bacteria were identified as Pseudomonas putida (S1), Citrobacter sp. (S4) and Enterobacter sp. (S5). These organisms not only decolourised effluent upto 97% but reduced BOD, COD, phenolics and sulfide upto 96.63, 96.80, 96.92 and 96.67% respectively within 24 hrs of aeration and the heavy metals were removed upto 82-99.80%. The TSS and TDS were sharply reduced due to degradation. The absorption maxima was also decreased to 90%. However, in control without the microbial consortium no noticeable change was produced.  相似文献   
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