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431.
王丽红 《中国环境管理干部学院学报》2007,17(4):119-121
目前,高校资产管理工作在管理意识、管理方法和管理手段等方面都明显滞后,难以适应高校建设与发展的要求。切实加强高校固定资产管理,就要树立全新的固定资产管理理念,建立科学、合理的保障制度,充分发挥财会、审计部门的重要作用,实现资源共建和共享,同时也要建立可行的资产管理绩效考核制度。 相似文献
432.
红厚壳野生资源的开发型保护途径分析 总被引:1,自引:0,他引:1
从红厚壳的生物学特性和具有的油用、药用、材用、观赏、生态保护等多种用途角度出发,针对砍伐严重的状况,提出通过驯化栽培、开发油脂应用范围和加强海岸防护林的设置来保护红厚壳;同时建议政府和科研部门重视并探索红厚壳在中药和油脂加工方面的价值。 相似文献
433.
Z. Liang L. Bdard-Tremblay L. Bauwens 《Journal of Loss Prevention in the Process Industries》2007,20(4-6):570-577
The structure of the steady planar detonation wave is analyzed for three-step chain-branching kinetics consistent with hydrogen–air chemistry. The initiation and chain-branching steps are described by an Arrhenius rate. Both are thermally neutral, so that heat release is due to termination. The initiation rate is typically very low and very stiff. As a result, a small fraction of the reactant is consumed in the initiation region, which is very long but ends in an exponential chain-branching explosion. Next, the reactant is rapidly converted into chain-branching radicals, within a very thin zone, which ends when the concentration of the chain-branching radical reaches a peak, because of reactant depletion. Finally, the termination step consumes the chain-branching radicals and releases heat within a region thicker than the peak zone, but much thinner than the initiation region. The analysis is based upon two assumptions: that the chain-branching activation energy is high and that initiation is slow. The structure of the initiation and chain-branching zones is different for post-shock states within or outside the explosion region in the chain-branching diagram. In the former situation, chain-branching is already stronger than termination at the von Neumann point, and vice versa. In the no-explosion case, the initiation zone becomes very long, while the little chain-branching specie produced by initiation is directly converted into product by the termination step. Temperature increases slowly until reaching the explosion curve, when chain-branching becomes stronger than termination. The subsequent structure is similar to the explosion case. 相似文献
434.
G. Baudry S. Bernard P. Gillard 《Journal of Loss Prevention in the Process Industries》2007,20(4-6):330-336
Some results of determination of ignition energies for an aluminium powder with various oxide contents are presented. Common use of processes like high-speed cutting produce explosive dust clouds, so that we focused this study on hazard of metallic powders. An industrial aluminium powder has been used for this work. An original process, based on the principle of electrochemical anodisation, has been developed to increase, under control, the oxide coating of particles.
The sensitivity study to spark ignition was performed in an Hartmann explosion tube of 1.3L. The Langlie test method was applied to evaluate the energies leading to a probability of ignition of 50% (E50) of the selected samples. The results confirm that the ignition energies increase with the oxide content of the powder. 相似文献
435.
Aslı Aksoy 《International Journal of Green Energy》2019,16(1):34-48
All economic sectors are associated with energy use; therefore, government organizations aim to supply sustainable energy for human needs and economic growth. In particular, increased environmental concerns of the public in Turkey have impacted policymaking for renewable energy (RE) management in Turkey. The primary objective for RE sources of the Turkish Ministry of Energy is to ensure that 30% of the share of electricity production is from RE resources in 2023. In this paper, the integrated multi-objective, multi-period linear programming model is presented to determine effective allocation of RE supply for seven different geographical regions in Turkey for the period of 2017 to 2024. The integrated model consists of two different stages. The first stage involves qualitative evaluations of RE sources for seven geographical regions. Analytical Hierarchy Process (AHP) is applied to determine criteria priorities and overall ratings of geographical regions across determined criteria for RE sources are computed. The second stage of the integrated model consists of a multi-objective, multi-period linear programming model. The proposed multi-objective linear programming model is coded in MPL (Mathematical Programming Language) and solved using the GUROBI 5.1.0 solver. The output of the integrated model presents the total supply amount of RE sources for geographical regions in planning period. The ε-constraints method is applied to compute the total supply amount of RE from geographical regions for the period of 2017 to 2024. In this study, a systematic decision-making model is generated to allocate renewable energy sources to the geographical regions. The presented model integrates qualitative evaluations and quantitative parameters of different geographical regions to determine the optimal supply amount of RE. The obtained results are consistent with the potential quantities of RE alternatives in geographical regions, regional specifications, and social requirements. 相似文献
436.
ABSTRACT. Planning an optimal system of activities for generating economic goods and services within an existing natural resource capacity is a difficult problem to solve. A mathematical programming model with the capacity to check multiple resource demand and supply compatibility over many time periods was developed for the solution to this type of problem. The characteristics of natural resource supply and the demand of activities were utilized to reduce the number of time periods and to minimize the loss of the dynamic reality of the problem. Reduction in the number of time periods extended the capability of the model to the solution of complex resource planning problems without oversimplification. 相似文献
437.
James Fulton William L. Chase 《Journal of the American Water Resources Association》1979,15(2):426-435
ABSTRACT: The Phoenix metropolitan area has a unique combination of circumstances which makes it one of the prime areas in the Nation for waste water reuse. Overriding all of these conditions is the long-term inadequacy of the existing water supplies. The Salt River Valley has a ground water overdraft of about 700,000 acre feet per year. To help alleviate this situation, the Corps of Engineers in conjunction with the MAG 208 is looking at ways to reuse a projected 2020 waste water flow of 340,000 acre feet per year. Reuse options identified include ground water recharge, agricultural irrigation, turf irrigation, recreational lakes, fish and wildlife habitats, and industrial cooling. These look nice on paper but before they can be implemented, some hard questions have to be answered, such as: How acceptable are local treatment plants when 15 years ago there was a major push to eliminate local plants; is the Phoenix area ready for reuse in urban areas; what are people willing to pay for water; who benefits if a city goes to ground water recharge; how much agriculture will be left in the area by 2020? These and other questions must be resolved if reuse is to become a viable option in water resource planning in the Phoenix area. Summary. Large scale reuse of waste water conforms with the national goal of better resource management through recycling. The Phoenix metropolitan area has a unique combination of circumstances which makes it one of the prime areas in the nation for waste water reuse. Some of the most notable conditions are: the existence of a large and rapidly growing urban area which is in the process of planning for future waste water management systems; the existence of agricultural areas which are projected to be farmed well into the future, and the existence of constructed and planned major recreational systems such as Indian Bend Wash which can use recycled waste water; the existence of extensive depleted ground water aquifers; the need for a dependable source for the cooling of the Palo Verde Nuclear reactors; and finally, overriding all of this, the long-term inadequacy of the existing water supplies. Given this, one would expect to find total reuse within the Phoenix metropolitan area. Reuse is taking place with irrigation and nuclear power cooling to the west but there is no long term plan which looks at the Valley as a whole and considers waste water as part of the Valley's water resources. The Corps 208 plan is looking at waste water in this manner but initial analysis shows that although reuse is technically feasible there are many financial, social, institutional, and political questions still to be answered. These include: determining the value of existing diminishing water sources and what people are willing to pay for the next source of water; are people willing to identify priority uses of water for the area so that water of varying quality is put to its highest and best use; will the present institutional boundaries remain to create water-rich and water-poor areas; and will legislation be forthcoming to simplify the complex surface and ground water laws that presently exist? The Corps 208 study will not be able to answer these questions, but the goal at the moment is to identify feasible reuse systems along with decisions the public, owners, agencies, and politicians must make to select and implement them. If some sort of logical process is not developed and public awareness not increased, the chance for a long-term plan to utilize waste water as a major element in the Phoenix area water resource picture, may be missed. 相似文献
438.
Marshall Flug Wynn R. Walker Gaylord V. Skogerboe 《Journal of the American Water Resources Association》1979,15(4):964-973
ABSTRACT: The Upper Colorado River Basin contains appreciable amounts of undeveloped fuel resources. Large quantities of oil shale, coal, and uranium have attracted recent economic and commercial interests. Development of these resources and subsequent conversion to alternative energy forms require an adequate supply of water. Water use for large scale energy development will place increasing demands on an already overstressed allocation of Colorado River water. Present water quality is at a concentration where increased salinity will result in economic detriments to holders of downstream water rights. The salt and water exchange in mining, processing, and spent fuel disposal processes has been incorporated as part of a two-level minimum cost linear programming algorithm. Mathematical simulation results provide an optimal use of Upper Colorado River water for levels of energy output such that salinity concentrations are maintained below predetermined levels. 相似文献
439.
E. Susan Boydstun Terry Nelson Roger B. Long 《Journal of the American Water Resources Association》1979,15(4):1086-1095
ABSTRACT: Public investments in water resource development projects are continually under scrutiny in terms of economic, environmental, and social impacts. Results of an analysis of a water development project that supplies irrigation water in Idaho are discussed in terms of the impact on income distribution and income growth 44 to 64 years after the project was initiated. Gini ratios for the rural farm population of these counties were consistently lower than they were for the United States as a whole and for the state of Idaho. In addition, income distributions tended to become more equitable over time in the water project counties. Rural farm population income growth rates were found to be similar to those for the nation as a whole. Some of the reasons for these results may be related to the tendency for income distribution to become more equitable as income increases, and the fact that average farm size is relatively small. 相似文献
440.
Earl C. Leatherberry 《Journal of the American Water Resources Association》1979,15(5):1281-1292
ABSTRACT: During the past 15 years a number of methods have been developed that purport to evaluate the amenity values of rivers. Most methods are designed to identify the physical, biological, cultural, and esthetic features of a river or river corridor that are conducive to recreation, preservation, and other amenity values. This paper reviews and comments on 13 methods that evaluate amenity values. The methods are reviewed and discussed under three general headings: River Recreation Potential Evaluation, River Esthetic Evaluation, and River Preservation Evaluation. A final section of the paper identifies areas where improvements and further research are needed. 相似文献