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11.
Feldspar, among many natural substances such as termitemount-clay, saw-dust, kaolinite and dolomite, offers asignificant removal ability for sulfate, phosphate, and coloredsubstances. Optimization of experimental parameters such assolution pH and flow rate reveals, that the maximum efficiency forremoval of phosphate, sulfate, and colored substances is about42, 52, and 73% respectively. X-ray diffraction, adsorptionisotherm and recovery studies suggest, that the removal processof anions occurs via ion exchange in conjunction with surfaceadsorption. Furthermore, reaction rate studies indicate thatthe removal of the selected pollutants by feldspar follows first-order kinetics. Although the percent removal, under the optimized conditions, is higher for laboratory prepared solutions, efficiency is a little less for industrial effluentsdue to interferent effects.  相似文献   
12.
This study evaluated the impacts of future climate change on the hydrological response of the Richmond River Catchment in New South Wales (NSW), Australia, using the conceptual rainfall-runoff modeling approach (the Hydrologiska Byrans Vattenbalansavdelning (HBV) model). Daily observations of rainfall, temperature, and streamflow and long-term monthly mean potential evapotranspiration from the meteorological and hydrological stations within the catchment for the period of 1972–2014 were used to run, calibrate, and validate the HBV model prior to the streamflow prediction. Future climate signals of rainfall and temperature were extracted from a multi-model ensemble of seven global climate models (GCMs) of the Coupled Model Intercomparison Project Phase 3 (CMIP3) with three regional climate scenarios, A2, A1B, and B1. The calibrated HBV model was then forced with the ensemble mean of the downscaled daily rainfall and temperature to simulate daily future runoff at the catchment outlet for the early part (2016–2043), middle part (2044–2071), and late part (2072–2099) of the 21st century. All scenarios during the future periods present decreasing tendencies in the annual mean streamflow ranging between 1% and 24.3% as compared with the observed period. For the maximum and minimum flows, all scenarios during the early, middle, and late parts of the century revealed significant declining tendencies in the annual mean maximum and minimum streamflows, ranging between 30% and 44.4% relative to the observed period. These findings can assist the water managers and the community of the Richmond River Catchment in managing the usage of future water resources in a more sustainable way.  相似文献   
13.
We provide new evidence on the monitoring benefits from institutional ownership by analyzing the impact of institutional ownership on stock price and operating performance following seasoned equity offerings, a setting where the effects of monitoring are likely to be especially important. We find that announcement returns are positively and significantly related to total and active institutional ownership levels and concentration. Post-issue stock returns are positively and significantly related to the contemporaneous post-issue changes in total and active institutional ownership and the concentration of their shareholdings. Operating performance improvements are also related to institutional monitoring in the one, two, and three years following the equity issue. Our results continue to hold even after accounting for the possibility that institutional investors have an informational advantage that enables them to identify and invest in subsequently better performing firms. We also empirically eliminate the possibility that our findings are driven by institutions buying past winners and selling past losers as a way to window-dress their portfolio holdings.  相似文献   
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15.
A model of interlinked credit-product contracts between small farmers and large farmers when the small farmer faces delay in getting formal credit and the large farmer does not, has been developed. The small farmer remains on the reservation income level, and his reservation income is inversely related to the length of the delay. However, this does not hamper the productivity of the small farmer. The large farmer extracts the surplus through the interlinked contract and this surplus is positively related to the length of the delay. Interlinkage and non-inter-linkage equilibria become identical if the small farmer gets the formal credit at the beginning of the crop cycle. Various subsidy policies worsen the distribution of formal credit.  相似文献   
16.
This study undertakes a longitudinal analysis of the ethical management practices of Sri Lankan companies by comparing the results from a survey conducted in 2003. During this period regulatory developments have taken place within Sri Lanka and internationally aimed at improving the level of corporate governance. Based upon this survey data we conclude that progress has been made in ensuring that ethical management practices are more homogenous and standard practice across companies. Internationalized companies remain the ones that are more aware of the environmental consequences of their actions, although few companies, unfortunately, recognize this as an issue of concern.  相似文献   
17.
Organizational governance has historically focused around the perspective of principals and managers and has traditionally pursued the goal of maximizing owner wealth. This paper suggests that organizational governance can profitably be viewed from the ethical perspective of organizational followers – employees of the organization to whom important ethical duties are also owed. We present two perspectives of organizational governance: Principal Theory that suggests that organizational owners and managers can often be ethically opportunistic and take advantage of employees who serve them and Principle Theory that focuses on guiding principles that are sometimes taken too far in organizations. In introducing these two new organizational governance perspectives, we offer insights into the value of rethinking ethical duties owed to organizational followers. Cam Caldwell received his Ph.D. from Washington State University where he was a Thomas S. Foley Graduate Fellow. Dr. Caldwell is Editor of the Academy of Management Ethics website and a member of the Academy’s Ethics Committee. His research is primarily in the areas of ethical leadership, organizational governance, and developing organizational trust. Prior to obtaining his Ph.D., Caldwell worked for 25 years as a city manager, human resource director, and management consultant. Ranjan Karri is Assistant Professor of Management at Bryant College. He received his Ph.D. in strategic management from Washington State University. His research interests include corporate and business strategies, ethical leadership and corporate governance. Pamela Vollmar is an undergraduate student at the University of Houston – Victoria majoring in Business Management. She has worked for 25 years as an electrical specialist for a major engineering firm.  相似文献   
18.
Evaluation of value of irrigation water is essential for supporting policy decision making relating to investments in the irrigation sector, efficient allocation of irrigation water and water pricing and for crafting policies to compare the variable impacts of water reform within and across sectors of the economy. This paper asks the question of how much an established irrigator would pay for water and at what price farmers planning to expand the area they have under irrigation would consider paying for the right to access water. An analytical framework is developed to estimate the net present value of both annual and perennial agricultural activities in the Murrumbidgee catchment. Using these estimates the total value of water used in Murrumbidgee catchment is estimated. An aggregate water supply curve is derived for the catchment from where water may be acquired from irrigators for environmental flows.  相似文献   
19.
Crop management innovations are often not discrete fixed stand‐alone options—and their adoption may imply various combinations and adaptations. This potentially confounds their impact assessment. This article assesses the resource saving and productivity enhancing impacts of a crop management package revolving around minimum tillage in maize‐based farming systems in northwest Ethiopia. An endogenous switching regression model was applied to plot‐ and household‐level survey data collected from 290 rural households operating 590 maize plots during the 2012 production year. Controlling for variations in plot and household characteristics, the average effect of minimum tillage package (minimum tillage package) on maize productivity is 0.44 t/ha. Compared to conventional practice (CP), adoption of the MTP decreased the average male and female labor use in maize production by 14.4 and 8.2 person‐days per ha, respectively. Similarly, MTP adoption decreased draft power use for land preparation by 13.2 pair of oxen‐days per ha. Compared to CP, in general, there is a considerable short‐run maize productivity gain and reduction in labor and draft power use under MTP.  相似文献   
20.
This paper develops a model of endogenous economic growth with special consideration to the role of productive public expenditure and environmental pollution; and analyses the properties of optimal fiscal policy in the steady state growth equilibrium. We consider the level of consumption as the source of pollution. Government allocates its tax revenue between pollution abatement expenditure and productive public expenditure. Optimum ratio of productive public expenditure to national income is equal to the competitive output share of the public input, when productive public expenditure is depicted as tax revenue minus abatement expenditure. However, the proportional income tax rate exceeds the competitive output share of the public input. There is no conflict between the social welfare maximizing solution and the growth rate maximizing solution in the steady state growth equilibrium. The unique steady state growth equilibrium appears to be a saddle-point when the growth rate is above a critical level and the steady state equilibrium growth rate in the market economy is not necessarily lower than the socially efficient growth rate.  相似文献   
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