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181.
为了采取合理的瓦斯抽采技术,实现矿井安全高效开采,对朱集矿13-1煤瓦斯基本参数进行了现场和实验室测定,得出了瓦斯含量、瓦斯压力、放散初速度,透气性系数、坚固性系数等参数,并对测定结果进行了理论分析,得出了这些参数的基本规律.结果表明:随着开采深度的增加,在一定深度范围内,其瓦斯压力、瓦斯含量呈线性增长,瓦斯压力与瓦斯含量都比较大;煤层钻孔瓦斯衰减系数较大,该煤层的透气性系数较小,D、K值小于其临界值,可判断出该煤层为难抽煤层且有突出危险性. 相似文献
182.
为了解决瓦斯排放孔半径测定过程中由于方法选择和操作等原因而出现的测定结果不够准确,以及由此而导致的空白带出现问题,通过现场试验,采用钻屑解吸指标法测定的方法,通过对测定结果进行综合分析、修正,确定安顺煤矿Φ42 mm直径的排放钻孔有效作用半径为R0.25 m,Φ90 mm直径的排放钻孔有效作用半径为R0.55 m,经实践证明是准确和可靠的,排放钻孔措施在实施过程中有效地避免了空白带的出现。 相似文献
183.
论述了我国新环境保护法,国家环境保护规划应当坚持保护优先、预防为主、综合治理、突出重点、全面推进的原则等;新修订的《环保法》要求建立资源环境承载能力监测预警机制;推动多元共治的现代环境治理体系是加大经济处罚的力度。设计了罚款的按日连续计罚规则;要求政府主管部门应当公开环境信息,应当制定和完善公众参与的程序,为公众参与环境监督提供便利等。最后进行了展望。 相似文献
184.
As a result of the '16-year drought' that Burkina Faso experienced from the late 1970s to the mid-1980s, there has been significant
movement of people from the north of the country to the south. The large numbers of people that were displaced as a result
of this natural disaster put pressure on the production systems of the south and caused concern amongst development organisations
that environmental degradation would follow. Through a 2-year research period, using participatory approaches, it was found
that despite a doubling of the population and the introduction of foreign production systems, the process of communal land
control has significantly limited environmental degradation. This paper explains how customary law has controlled the settlement
of immigrants (the Mossi and Fulani) and how it has overseen land allocation in three villages. The conclusions of the study
indicate that, firstly, the customary law mechanisms in the three villages are effective in addressing communal resource use
and, secondly, there is an evolution in customary law systems as they respond to local change.
Received: 24 February 1999 · Accepted: 15 May 1999 相似文献
185.
Donald N. Jeffs R. Peter Dennis 《Journal of the American Water Resources Association》1973,9(1):41-48
ABSTRACT. Most water takings in Ontario in excess of 10,000 gallons per day for purposes other than domestic, farm, or fire fighting require authorization by permit by the Ontario Ministry of the Environment. The legislation imposes control beyond that under common law, but does not remove common-law obligations. Permits may not be assigned without the Ministry's consent and do not create property rights in water. Permits to take ground-water require permittees to ensure that sufficient water is made available for the needs of prior users who suffer serious water-supply interference due to the taking, or to reduce the rate and amount of taking. Permits to take surface water require permittees to maintain sufficient downstream flow to protect downstream uses of water and natural functions of streams. Specific permit requirements for city wells in the rural Hunsburger Creek basin protect existing well supplies and require maintenance of streamflow for pond levels and fish. Tobacco irrigation in the Big Creek basin reduced streamflow significantly and requires development of more detailed water-management plans for years of extreme demand. Ontario's permit program serves to resolve water-use conflicts, furnishes information on use and provides one means for implementing management plans. 相似文献
186.
George E. Radosevich Evan C. Vlachos Gaylord V. Skogerboe 《Journal of the American Water Resources Association》1973,9(2):352-359
ABSTRACT Whether the goal is minimizing water quality degradation in receiving streams or maximizing agricultural production on existing croplands; the solutions are identical - improved water management practices. Technology has succeeded in developing feasible solutions to improving irrigation water management, but the law has been slow to encourage or direct implementation. The villain of the western United States water problem is the property right concept of the appropriation doctrine. Improving water management also implies organizational improvements. Also, the so-called “human factor” involves questions of inefficiency and ineffectiveness, that when examined under the criteria of efficacy, may dictate a policy of continuing present practices in certain localities or regions with little technological intervention. The present effort for improving water quality management implies, therefore, a manyfold attack aimed at increasing project irrigation efficiency and effectiveness, under the larger rubric of efficacy and the achievement of larger social goals. 相似文献
187.
Dale R. Ralston 《Journal of the American Water Resources Association》1973,9(5):908-917
ABSTRACT: Ground water is intended to be administered in many western states as a flow or renewable resource. In Idaho, this administration is based on the appropriation doctrine of water rights. Two generalizations may be made concerning ground water. First, water artificially discharged from an aquifer system must deplete the total resource by that amount; water consumptively pumped from a well must be derived from either increased recharge, decreased discharge or a decrease of water in storage. Second, the annual rate of recharge to a ground-water system is often only a small percentage of the total resource in storage. Ground water may be divided into flow and stock portions. In those basins where the second generalization is true, most ground water may be classified as stock. However, only the flow portion of ground water may be developed if utilization of the resource is to be enjoyed over an infinite period. Data from the Raft River Basin in Idaho indicate that the flow and stock characteristics of ground water are time dependent. The resource exhibits the characteristics of both a renewable and nonrenewable resource. As a result, present administrative techniques do not provide for effective management of the resource. 相似文献
188.
ABSTRACT: Temporary transfers of water for dry year water supply are analyzed for cost and operational feasibility. The temporary transfer is implemented as part of a water rights option agreement (WROA) between a lesson and a lessee. First, engineering analysis determines the technical feasibility and operations plan under the Colorado doctrine of prior appropriation. The cost of the WROA to a water utility is estimated. Other considerations in the agreement are discussed. The WROA is compared to other dry-year supply alternatives using a water system simulation model to obtain expected cost and operational performance characteristics. 相似文献
189.
Victor E. Gleason 《Journal of the American Water Resources Association》1978,14(3):532-541
ABSTRACT: California's courts have recently recognized the existence of underground aquifer storage rights that permit public agencies to (1) store imported waters in aquifers; (2) prevent others from expropriating that water; and (3) recapture the stored water when it is needed. The article describes the two appellate decisions that represent the common-law development of aquifer storage rights. Each decision related to separate aquifers that were subject to separate types of groundwater management programs. One decision involved an aquifer under the southeastern San Francisco Bay area that was managed under statutory authority and is entitled, Niles Sand and Gravel Co. v. Alameda County Water District 37 C.A.3d 924 (1974); cert. denied 419 US 869. The other decision involved an aquifer under Southern California's San Fernando Valley that was managed under judicial authority and is entitled, City of Los Angeles v. City of San Fernando 14 Cal.3d 199 (1975). The two decisions provide separate, but complimentary, public interest rationales for aquifer storage rights: (1) to protect water supplies necessary for the overlying community; and (2) to increase water supply efficiencies by using natural underground reservoirs wherever practicable. The Article reviews the relationship of aquifer storage rights to conventional groundwater rights and indicates aspects of the storage right that may need additional development. 相似文献
190.
Keith W. Muckleston Richard M. Highsmith 《Journal of the American Water Resources Association》1978,14(5):1121-1128
ABSTRACT: As of 1976 over 225,000 acres were being irrigated by center pivot units in a five-county area of the Columbia Basin in Oregon and Washington. Most of the development took place since 1970. Dynamic application of center pivot technology altered the concept of irrigability in the study area, converting lands that were often rolling, sandy, and plagued by wind erosion from low grade grazing to productive irrigated units. This development was entirely by private enterprise, with large corporate farms accounting for much of the effort. Little prior comprehensive planning or coordination took place. When the circulation of water is altered on such a massive scale, however, unplanned impacts may be far reaching. In this case they include:1) acceleration of the shift to high cost thermoelectric generation, 2) alteration of state institutions designed to allocate water, and 3) possible significant alterations of the socioeconomic fabric of small rural service centers. 相似文献