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As our society's environmental concerns have grown over the past 20 years, U.S. firms have struggled to find effective and inexpensive ways to meet their mushrooming environmental obligations. Many firms, recognizing the competitive advantages to be won through adroit environmental management, have begun to seek managers trained to deal with these issues. The corporate response has been hobbled by business schools'general failure to train managers to deal with crossfunctional issues, and by a specific failure to address environmental management in their curricula. In this article, the Management Institute for Environment and Business, a program of the World Resources Institute (WRI), describes its innovative University-Community Partnerships (UCP) project to address these shortcomings. Bringing new approaches and new thinking to management curricula, MEB and several like-minded organizations are breathing new life into the old MBA programs.  相似文献   
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The salient features of the river water chemistry and the seasonal variations on the individual chemical parameter were evaluated and characterized. The order of abundance of the ions in the water is determined for both seasons. The contribution of chemical weathering to the water chemistry has been determined using the (Ca2+ + Mg2+)/(Na+ + K+) ratio, ternary, and Gibb’s diagrams. The results show that the chemical composition of river water during premonsoon is controlled mainly by evaporation–crystallization, while in the postmonsoon, the rock–water interaction dominates. The unique characteristic of the river water is the linear relationship among the principal ions. Hydrochemical characteristics of ions in the water were studied using 1:1 equiline diagrams. The nature of the water samples was determined using the piper diagram. The influence of trace metals on the chemical composition and the quality of the river water in the study area has been assessed using Wilcox and US Salinity Laboratory diagrams.  相似文献   
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The formation of ultrafine particles, their growth, and associated characteristic features has been studied during new particle formation events over a high-altitude station of the Western Ghats during the 2014 post-monsoon season. Most of the events were observed during noon time where particle bursts in the nucleation-mode size range from 5 to 25 nm followed by sustained growth in size. This phenomenon persists for ~4–8 h with a growth rate of 1–2 nm h1. Peak concentrations of nucleation-mode particles during the event generally vary from 2300 to 5000 cm3. The mean growth rate is 1.4 ± 0.42 nm h1, particle formation rate is 1.14 ± 0.22 cm3 s1, coagulation sink is 0.35 ± 0.22 cm3 s1, and condensational sink is 15.4 ± 2.6?×?103 s1. All these values are comparable with earlier results from Indian region. Comparison of size-segregated particle number concentration during days of new particle formation events and those without new particle formation were carried out showing a distinct variation in nucleation and Aitken mode with least variability associated with the accumulation mode.  相似文献   
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The present study was carried out to isolate bacteria capable of producing biosurfactant that solublize endosulfan (6,7,8,9,10,10-Hexachloro-1,5,5a,6,9,9a-hexahydro- 6,9-methano-2,4,3-benzodioxathiepine-3-oxide) and for enhanced degradation of endosulfan and its major metabolite endosulfate. The significance of the study is to enhance the bioavailability of soil-bound endosulfan residues as its degradation is limited due to its low solubility. A mixed bacterial culture capable of degrading endosulfan was enriched from pesticide-contaminated soil and was able to degrade about 80% of α-endosulfan and 75% of β-endosulfan in five days. Bacterial isolates were screened for biosurfactant production and endosulfan degradation. Among the isolates screened, four strains produced biosurfactant on endosulfan. ES-47 showed better emulsification of endosulfan and degraded 99% of endosulfan and 94% of endosulfate formed during endosulfan degradation. The strain reduced the surface tension up to 37 dynes/cm. The study reveals that the strain was capable of degrading endosulfan and endosulfate with simultaneous biosurfactant production.  相似文献   
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A batch adsorption process was applied to investigate the removal of perchlorate (ClO4 ?) from water by graphene. In doing so, the thermodynamic adsorption isotherm and kinetic studies were also carried out. Graphene was prepared by a facile liquid-phase exfoliation. Graphene was characterized by Raman spectroscopy, Fourier-transform infrared spectroscopy, powder X-ray diffraction, scanning electron microscope, and zeta potential measurements. A systematic study of the adsorption process was performed by varying pH, ionic strength, and temperature. The adsorption efficiency of graphene was 99.2 %, suggesting that graphene is an excellent adsorbent for ClO4 ? removal from water. The rate constants for all these kinetic models were calculated, and the results indicate that second-order kinetics model was well suitable to model the kinetic adsorption of ClO4 ?. Equilibrium data were well described by the typical Langmuir adsorption isotherm. The experimental results showed that graphene is an excellent perchlorate adsorbent with an adsorbent capacity of up to 0.024 mg/g at initial perchlorate concentration of 2 mg/L and temperature of 298 K. Thermodynamic studies revealed that the adsorption reaction was a spontaneous and endothermic process. Graphene removed the perchlorate present in the water and reduced it to a permissible level making it drinkable.  相似文献   
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针对传统教与学算法在解决复杂多峰函数优化问题时,具有局部最优且搜索开发能力较差的缺点,提出了一种改进的多学习教与学优化算法,新算法为学员的每一维加入不同的教学因子,设计了基于学员均值比较的教师选择策略和向教师及学员学习的多学习策略。基于多个单峰和多峰函数的仿真结果表明,新算法跟传统的、改进的教与学算法相比,在稳定性、寻优精度和收敛速度方面更具优势。  相似文献   
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Objective: India has been slow in implementing a central emergency medical services (EMS) system across the country. “108 services” is one of the most popular services that is functional under the public–private partnership model. Limited available literature shows that despite access to services, many traffic crash victims are transported using private vehicles. The objective of this study is to understand the effectiveness of 108 services from a traffic safety perspective.

Method: A questionnaire survey is conducted to understand the awareness of EMS and their function. Using traffic-related fatalities as the dependent variable, a fixed effect panel data model is developed to analyze the effectiveness of the 108 services in improving the traffic safety.

Results: The results from the survey show that, in general, people are not aware of the 108 services. A majority of the population prefers taking victims to the hospital using their personal vehicles or any other vehicles available compared to calling an ambulance. Results from panel data analysis show that despite having an efficient system, these services failed to make significant improvement in the safety of road users in the states in which their services were subscribed.

Discussion: The lack of awareness of an important safety service is alarming. This could be a major reason for lower utilization of 108 services for transporting victims of traffic crashes. This article shows the importance of having efficient awareness campaigns to improve the efficiency of any similar programs that are aimed to enhance the safety of a region.  相似文献   

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