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91.

The present study attempts to assess the literacy levels of future managers of India in social, economic, and environment sustainability issues both at national and global levels among the students from Management Education Institutions (MEIs) located in Bengaluru, Chandigarh, and New Delhi. Additionally, a comparative study between the MEIs situated in Bengaluru, Chandigarh, and New Delhi, India, is undertaken. Interestingly, participants of the study specified more professional importance and personal relevance of sustainability. The study's outcome shows a higher level of sustainability knowledge among future managers from MEIs in New Delhi and Bengaluru. Future managers based out in New Delhi and Bengaluru are more aware of social and economic sustainability and having less awareness of environmental issues. Sustainability knowledge and awareness of the future managers are the first steps to engage them in building a sustainable future. It compels them to remain fully dedicated to creating a prosperous society and encourages them to make knowledgeable and successful choices to that end. The study's findings indicate a difference found in the levels of sustainability literacy among the Postgraduate students of Business Administration based in India's three metropolitan cities, including Chandigarh: Bengaluru and Delhi. The awareness about the local, national, or global eco-system, pollution, and other problems concerned with the environment was low among students based in Chandigarh, moderate among Delhi students, and high among the Bengaluru students.

  相似文献   
92.
Application of Amberlite XAD-7 impregnated with morpholine dithiocarbamate (MDTC) for separation and preconcentration of trace amounts of lead, copper, cobalt, iron, nickel, cadmium and zinc and determination by ICP-AES has been described. The optimum experimental parameters, such as pH, sample flow rate, eluent and effect of matrix ions on the preconcentration were investigated. Simultaneous enrichment of the seven metals was accomplished. The t 1/2 values for sorption are 2.9, 3.3, 3.7, 3.6, 2.8, 4.1 and 2.8 respectively for Pb(II), Cu(II), Co(II), Fe(III), Ni(II), Cd(II) and Zn(II). The method was applied for the determination of trace metal ions in seawater and natural water samples. The results have been compared with extraction GFAAS method.  相似文献   
93.
In order to search the degradability of kraft lignin, the potential bacterial strains Bacillus subtilis (GU193980) and Klebsiella pneumoniae (GU193981) were isolated, screened and applied in axenic and co-culture conditions. Results revealed that mixed culture showed better decolorization efficiency (80%) and reduction of pollution parameters (COD 73% and BOD 62%) than axenic culture. This indicated syntrophic growth of these two bacteria rather than any antagonistic effect. The HPLC analysis of degraded samples of kraft lignin has shown the reduction in peak area compared to control, suggesting that decrease in color intensity might be largely attributed to the degradation of lignin by isolated bacteria. Further, the GC–MS analysis showed that most of the compounds detected in control were diminished after bacterial treatment. Further, the seed germination test using Phaseolus aureus has supported the detoxification of bacterial decolorized kraft lignin for environmental safety. All these observations have revealed that the developed bacterial co-culture was capable for the effective degradation and decolorization of lignin containing rayon grade pulp mill wastewater for environmental safety.  相似文献   
94.
Chaturvedi PK  Seth CS  Misra V 《Chemosphere》2006,64(7):1109-1114
Release of heavy metals onto the soil as a result of agricultural and industrial activities may pose a serious threat to the environment. This study investigated the kinetics of sorption of heavy metals on the non-humus soil amended with (1:3) humus soil and 1% hydroxyapatite used for in situ immobilization and leachability of heavy metals from these soils. For this, a batch equilibrium experiment was performed to evaluate metal sorption in the presence of 0.05 M KNO(3) background electrolyte solutions. The Langmuir isotherms applied for sorption studies showed that the amount of metal sorbed on the amended soil decreased in the order of Pb(2+)>Zn(2+)>Cd(2+). The data suggested the possibility of immobilization of Pb due to sorption process and immobilization of Zn and Cd by other processes like co-precipitation and ion exchange. The sorption kinetics data showed the pseudo-second-order reaction kinetics rather than pseudo-first-order kinetics. Leachability study was performed at various pHs (ranging from 3 to 10). Leachability rate was slowest for the Pb(2+) followed by Zn(2+) and Cd(2+). Out of the metal adsorbed on the soil only 6.1-21.6% of Pb, 7.3-39% of Zn and 9.3-44.3% of Cd leached out from the amended soil.  相似文献   
95.
Evaluation of biological effects using a rapid, sensitive and cost effective method can indicate specific information on toxicity/ecotoxicity. Since assays based on animals, plants and algae are expensive, time consuming and require large sample volume, recent studies have emphasized the benefits of rapid, reproducible and cost effective bacterial assays for toxicity screening and assessment. This review focuses on a bacterial assay, i.e., Vibrio fischeri bioluminescence inhibition assay, which is often chosen as the first test in a test battery based on speed and cost consideration. The test protocol is simple and was originally applied for aqueous phase samples or extracts. The versatility of the assay has increased with subsequent modification, i.e., the kinetic assay for turbid and colored samples and the solid phase test for analyzing sediment toxicity. Researchers have reported the Vibrio fischeri bioluminescence assay as the most sensitive across a wide range of chemicals compared to other bacterial assays such as nitrification inhibition, respirometry, ATP luminescence and enzyme inhibition. This assay shows good correlations with other standard acute toxicity assays and is reported to detect toxicity across a wide spectrum of toxicants.  相似文献   
96.
This study proposes a practical method to estimate elemental composition and distribution in order to attribute source and quantify impacts of aerosol particles at an urban region in Kolkata, India. Twelve-hour total particulates were collected in winter (2005–2006) and analyzed by energy-dispersive X-ray fluorescence technique to determine multi-elemental composition, especially trace metals. The aerosols consist of various elements including K, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Se, and Pb which exhibit significant concentration at various sites (p?<?0.05). The concentration of different metallic elements were found in the order of Zn ?> ?Pb ?> ?Ni ?> ?Cu ?> ?Cr ?>? Co. Statistical multivariate analysis and correlation matrix analyses were performed for factor identification and consequent source apportionment. Contour profiles demonstrate spatial variation of elemental compositions indicating possible source contribution along with meteorological influences. Spatial differences were clearly most significant for Zn, Ni, Pb, and Cu reflecting the importance of anthropogenic inputs, primarily from automobile sources.  相似文献   
97.
The present study describes the assimilation of di-n-octyl phthalate by an aerobic bacterium, isolated from municipal waste-contaminated soil sample utilizing di-n-octyl phthalate as the sole source of carbon and energy. The isolate was identified as Gordonia sp. based on the morphological, nutritional and biochemical characteristics as well as 16S rRNA gene sequence analysis. A combination of chromatographic and spectrometric analyses revealed a complete di-n-octyl assimilation pathway. In the degradation process, mono-n-octyl phthalate, phthalic acid, protocatechuic acid and 1-octanol were identified as the degradation products of di-n-octyl phthalate. Furthermore, phthalic acid was metabolized via protocatechuic acid involving protocatechuate 3,4-dioxygenase while 1-octanol was metabolized by NAD+-dependent dehydrogenases to 1-octanoic acid, which was subsequently degraded via β-oxidation, ultimately, leading to tricarboxylic acid cycle intermediates. Apart from phthalic acid and 1-octanol metabolizing pathway enzymes, two esterases, di-n-octyl phthalate hydrolase and mono-n-octyl phthalate hydrolase involved in di-n-octyl phthalate degradation were found to be inducible in nature. This is the first report on the metabolic pathway involved in the complete degradation of di-n-octyl phthalate by a single bacterial isolate, which is also capable of efficiently degrading other phthalate esters of environmental concern having either shorter or longer alkyl chains.  相似文献   
98.
A fluorometric method developed for measuring low concentrations of ammonium in marine and freshwater ecosystems was adapted for the analysis of ammonia in ambient air. The modified method entails collection of samples on an acid-treated solid adsorbent followed by analysis using a fluorometer. Optimal results were obtained using a commercially available sorbent tube containing 100 mg of acid-treated silica gel for sample collection, and an analytical protocol consisting of sample desorption in DI water, addition of orthopthaldialdehyde (OPA) working reagent, and room temperature incubation. Method accuracy and precision were evaluated by comparing experimentally determined quantities of ammonia to expected levels for sample loadings ranging from 0.16 [micro sign]g to 550 [micro sign]g-accuracy was generally within +/-20%. The estimated LOQ for the method is 0.08 [micro sign]g ammonia per sample which represents a 25-375-fold improvement in sensitivity compared to current NIOSH and OSHA methods for the measurement of ammonia in ambient air. The new method should be useful for applications requiring measurement of low concentrations of ammonia using personal sampling equipment or in the characterization of short-term fluctuations of ammonia concentrations in air.  相似文献   
99.
100.
Isoproturon (IPU)-degrading soil bacteria were isolated from herbicide-applied wheat fields. These isolates were identified using cultural, morphological, biochemical and 16S rRNA sequencing methods. 16S rRNA sequences of both the bacterial isolates were compared with NCBI GenBank data base and identified as Bacillus pumilus and Pseudoxanthomonas sp. A soil microcosm study was carried out for 40 days in six different treatments. Experimental results revealed maximum 95.98% IPU degradation in treatment 6 where bacterial consortia were augmented in natural soil, followed by 91.53% in treatment 5 enriched with organic manure as an additional carbon source. However, only 14.03% IPU was degraded in treatment 1 (control) after 40 days. In treatments (2–4), 75.59%, 70.92% and 77.32% IPU degradation was recorded, respectively. IPU degradation in all the treatments varied significantly over the control. 4-Isopropylaniline was detected as IPU degradation by-product in the medium. The study confirmed that B. pumilus and Pseudoxanthomonas sp. performed effectively in soil microcosms and could be employed profitably for field-scale bioremediation experiments.  相似文献   
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