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911.
依据对国内大气科学及相关机构进行广泛调研获取的数据, 重点从人才队伍、科研项目及科技论文产出几方面对国内大气科学发展状况进行了综述。 研究表明, 20世纪90年代以来我国大气科学不断发展, 大气科学与其他学科的交融日益增强。 大气科学队伍总量大, 人员分布广, 但高层次人才明显不足。 基于调研数据还从计量学角度对大气科学的研究现状, 国内、国际热点以及国内需求进行了比较研究, 列举4个判据, 从4种不同角度分析我国大气科学优先领域。 初步分析表明: 不论重视基础研究还是应用研究, 人工影响天气和大气物理领域应是优先资助领域; 重视科学热点和科技前沿, 应优先资助气候系统与全球变化和天气动力学理论与天气预报领域; 重视发展需求与科技前沿结合, 应优先资助大气化学和综合探测系统与外场科学试验领域。 相似文献
912.
针对当前计算机网络的特点,从地震科技信息介质的转变,资源的开发、利用,管理、保障体系的完善,服务方式的改变等方面进行了论述,指出,要充分利用网络资源,使地震科技信息更及时、准确、全面地为防震减灾事业服务。 相似文献
913.
914.
Effect of high-pressures on the electrical resistivity of natural zeolites from Deccan Trap, Maharashtra, India 总被引:1,自引:0,他引:1
G. Parthasarathy 《Journal of Applied Geophysics》2006,58(4):321
We report here the electrical resistivity measurements on two natural zeolites–natrolite and scolecite (from the Killari borehole, Maharashtra, India) as a function of pressure up to 8 GPa at room temperature. High-pressure electrical resistivity studies on hydrous alumino-silicate minerals are very helpful in understanding the role of water in deep crustal conductivities obtained from geophysical models. The results obtained by magneto-telluric (MT) soundings and direct current resistivity surveys, along with the laboratory data on the electrical resistivity of minerals and rocks at high-pressure–temperature are used to determine the electrical conductivity distribution in continental lithosphere. The electrical resistivity of natural natrolite decreases continuously from 2.9 × 109 Ω cm at ambient condition to 7.64 × 102 Ω cm at 8 GPa, at room temperature. There is no pressure-induced first order structural phase transitions in natrolite, when it is compressed in non-penetrating pressure transmitting medium up to 8 GPa. On the other hand scolecite exhibits a pressure-induced transition, with a discontinuous decrease of the electrical resistivity from 2.6 × 106 to 4.79 × 105 Ω cm at 4.2 to 4.3 GPa. The observed phase transition in scolecite is found to be irreversible. Vibrational spectroscopic and X-ray diffraction studies confirm the amorphous nature of the high-pressure phase. The results of the present high-pressure studies on scolecite are in good agreement with the high-pressure Raman spectroscopic data on scolecite. The thermo gravimetric studies on the pressure-quenched samples show that the samples underwent a pressure-induced partial dehydration. Such a pressure-induced partial dehydration, which has been observed in natural scolecite could explain the presence of high conductive layers in the earth's deep-crust. 相似文献
915.
杨梅洲木鱼湖断裂位于湘潭城区,要查明其位置和性质,地球物理勘探干扰因素多,施工条件不好。调查中分别采用天然电场选频法、高密度电阻率法和地质雷达等方法进行勘探,并通过开挖等方式进行验证,3种物探方法各有特点:天然电场选频法仪器轻便、勘探线布置灵活,干扰因素较少,工作效率高,特别是利用其动态信息确定断层平面位置准确;高密度电阻率法勘探结果比较直观,特别是对断层性质的确定形象,但勘探布极的工作量较大,受地形等因素影响较大,在城区很多地方无法正常开展工作;地质雷达勘探成果形象直观,但设备成本高,勘探受地形等因素影响大,勘探深度有限,一般对表层效果较好。 相似文献
916.
917.
Operationalising sustainability science for a sustainability directive? Reflecting on three pilot projects 总被引:3,自引:0,他引:3
The implementation of the Water Framework Directive (WFD) will challenge traditional single discipline or single issue approaches to research, requiring instead new forms such as 'sustainability science'. Sustainability science requires the integration of multiple perspectives to resolve place-based problems. This paper will illustrate some of the challenges and emergent understandings that were observed during three research projects that could be characterised as attempting to practice sustainability science. The first two projects focused on designing and developing an integrated assessment approach to analyse possible programmes of measures for the WFD. The third project is an evaluation of a European project that piloted specific measures that might be implemented under WFD. The findings highlight the institutional changes required to deliver sustainability science. To summarise, both the 'rules-in-use' and the 'play-of-the-game', to use the language of the institutional analysis and development framework, will have to change to provide sufficient incentives to make the transition from traditional science to sustainability science. 相似文献
918.
Thomas G. Measham 《The Australian geographer》2007,38(2):145-159
Community-based natural resource management (CBNRM) continues to attract interest as a way of achieving social and environmental outcomes at the local and regional scale. Central to the success of CBNRM is the importance of capacity building and participatory approaches to research and management. This paper discusses an initiative in East Gippsland which involved a facilitated process to assist local residents build their capacity to manage their landscape. Through conducting a community survey, the project facilitated landholders to voice, develop and refine their understanding of remnant vegetation management, dieback and revegetation on private land. In doing so, landholders have improved not only their understanding of the issues but also their ability to act upon them. The empirical findings of the study highlight two issues of relevance to dieback on the East Gippsland Red Gum Plains. First, there is a perception that dieback has remained stable for at least 10 years. Second, scattered trees and small patches of trees are more vulnerable to dieback than clumped trees in larger patch sizes, as well as roadside vegetation. The research demonstrates the value of a community-based approach to NRM in terms of harnessing local knowledge, fostering human and social capital and engaging with interested landholders. 相似文献
919.
The aquifer system of the Basin of Mexico is the main source of water supply to the Mexico City Metropolitan Zone. Management of the Basin’s water resources requires improved understanding of regional groundwater flow patterns, for which large amounts of data are required. The current study analyses the regional dynamics of the potentiometric groundwater level using a new database called the Basin of Mexico Hydrogeological Database (BMHDB). To foster the development of a regional view of the aquifer system, data on climatological, borehole and runoff variables are part of the BMHDB. The structure and development of the BMHDB are briefly explained and then the database is used to analyze the consequences of groundwater extraction on the aquifer’s confinement conditions using lithology data. The regional analysis shows that the largest drawdown rates are located north of Mexico City, in Ecatepec (a region that has not yet received attention in hydrogeological studies), due to wells that were drilled as a temporary solution to Mexico City’s water-supply problem. It is evident that the aquifer has changed from a confined to an unconfined condition in some areas, a factor that is responsible for the large subsidence rates (40 cm/year) in some regions. 相似文献
920.