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101.
对"岩矿分析质量要求和检查办法"的建议 总被引:1,自引:0,他引:1
剖析了现行“岩矿分析质量要求和检查办法”存在的问题。建议对该行业标准进行必要的修正;充分考虑地质找矿、矿床评价、地学研究的实际需要,认真考虑国民经济有关部门对矿产资源应用的实际情况;全面深入细致考虑测试技术的实际水平并注意其经济性,避免按一种模式随意缩小或放大双差的允许范围;避免岩矿分析质量检查工作繁琐不便。 相似文献
102.
103.
DIFFERENCES BETWEEN DRY AND WET SUMMER IN THE VERTICAL MOTION ON NORTH SIDE OF QINGHAI-XIZANG PLATEAU AND THE THERMAL IMPACT OF PLATEAU* 下载免费PDF全文
To better analyse and understand the causes of Northwest China(NW China) arid climate formation,firstly the dry and wet standards were chosen and the yearly dry and wet grades on the north side of Qinghai-Xizang Plateau(hereafter NSQXP) in summers were classified utilizing the rainfall data of five stations over the area in June-August of 1952-1990.Then the differences between the vertical motion over the Qinghai-Xizang Plateau(QXP) and NSQXP in dry and wet summers were comparatively analyzed using the ECMWF's gridded data of June-August of 1979-1986.Finally the connection between the QXP surface thermal condition and the dry and wet summers on the NSQXP was discussed as well.The main results are the following:(1)the dry and wet standards taking the rainfall standard deviation as criterion are suitable for the arid climate area;(2)the QXP may be,to some extent responsible for the environment background of Middle Asia,NW China and North China arid climate areas;(3)there are the striking differences between the dominant vertical motion over the QXP and NSQXP in the dry and wet summers of NSQXP:(4)the QXP surface thermal condition is to a great extent,responsible for the year-to-year variation of NW China arid climate as well. 相似文献
104.
Public support for stringent climate policies is currently weak. We develop a model to study the dynamics of public support for climate policies. It comprises three interconnected modules: one calculates policy impacts; a second translates these into policy support mediated by social influence; and a third represents the regulator adapting policy stringency depending on public support. The model combines general-equilibrium and agent-based elements and is empirically grounded in a household survey, which allows quantifying policy support as a function of effectiveness, personal wellbeing and distributional effects. We apply our approach to compare two policy instruments, namely carbon taxation and performance standards, and identify intertemporal trajectories that meet the climate target and count on sufficient public support. Our results highlight the importance of social influence, opinion stability and income inequality for public support of climate policies. Our model predicts that carbon taxation consistently generates more public support than standards. Finally, we show that under moderate social influence and income inequality, an increasing carbon tax trajectory combined with progressive revenue redistribution receives the highest average public support over time. 相似文献
105.
106.
In recent years, the increase in the number of hurricanes and other costal hazards in the US pose a tremendous threat to the residents of coastal states. According to the National Hurricane Center, Florida is the most vulnerable coastal state to hurricanes. Mitigation policies have been formulated to reduce mortality and provide emergency services by evacuating people from the hazard zone. Many of these evacuees, particularly the elderly or lower income populations, rely on evacuation shelters for temporary housing. Because of the cost and limited use, evacuation shelters are almost exclusively dual use shelters where the primary purpose of the facility is for some other public function (e.g. school, hospital, etc.). In 2000, the estimated shortage of public shelter spaces in Florida was about 1.5 million. The purpose of this study was to rank the existing and candidate shelters (schools, colleges, churches and community centers) available in the state based on their site suitability. The research questions examined in this study include: (1) How many candidate shelters are located in physically suitable areas (e.g. not in a flood prone area, not near hazardous facilities, etc.)?; (2) How many existing shelters are located in physically un suitable areas, but in socially suitable areas (situated in areas with demand)?; (3) How many alternative existing and/or candidate shelters with high/very high physical suitability are located near physically un suitable existing shelters and thus, may be better choices for a shelter?; and (4) How many existing shelters located in physically un suitable areas are not near alternative existing and/or candidate shelters? A Geographic Information System‐based suitability model integrating Weighted Linear Combination (WLC) with a Pass/Fail screening technique was implemented for the 17 counties of Southern Florida. It was found that 48% of the existing shelters are located in physically unsuitable areas. Out of all the candidate shelters, 57% are located in physically unsuitable areas. For 15 of the existing shelters in unsuitable locations, no alternative candidate or existing shelter with medium to high physical suitability exists within 10 miles (16.1 km). 相似文献
107.
For the past five years the Millsaps Sorbent Laboratory has been actively engaged in developing standards for initial and long-term oil spill remedial technologies. As a voting member of the American Society of Testing Materials (ASTM) F-20 Committee, Canadian General Standards Board, and the US Coast Guard Sorbents Task Force, the laboratory has been engaged in developing useful, pragmatic protocols for various chemical and physical sorbent and filtration technologies driven by the deadlines imposed by the Oil Pollution Act of 1990 (OPA 90). The open border approach to certification of technologies and products promulgated by the US/Canadian Free Trade Agreement has placed the US users and producers of such products and systems in a unique and tenuous position. Canadian standards and goals are grandfathered into the United States under this agreement and products have official US government certification based on Canadian regulations. This situation is unfavorable to the US domestic environment and economy for several specific scenarios. Included in these scenarios are: abundant warmwater zones and inland waters of the US versus Canada, the basic chemical variation between Canadian and US crude oils, the different generally accepted remediation technologies in the US versus Canadian, and the technology validation procedures prior to purchase inherent to both countries. 相似文献
108.
以白家疃地震台为实验点,于2008年3月21日完成对该台九五前兆仪器针对十五台网进行整合改造。通过为期13个月的运行结果可以看出,其改造方案成本低,技术可行,产出数据可靠,为九五前兆台站整体接入十五管理系统提供了低成本、高效可靠的技术参考。 相似文献
109.
A review is given of the development of systems of photometric standard stars at the South African Astronomical Observatory. A brief historical perspective indicates how the Harvard E-regions were chosen as standard sequences and developed into a very precise Southern hemisphere system for UBV(RI)
c
photometry. Subsequent additions of Strömgrenuvby - H and DDO photometry to samples of E-region stars and UBV(RI)
c
extensions to the F-regions and the Magellanic Clouds are also described. Current programmes to extend and improve these standard stars are briefly discussed, as well as the long-standing problem of linking the Northern and Southern systems. 相似文献
110.
In China, the distribution of water resources is incompatible with the development of productivity. The construction of South-to-North Water Diversion Project has achieved inter-basin water diversion, and the project can alleviate the uneven distribution of water resources phenomenon effectively. However, in recent years, the aggregate effects of water pollution and water resource shortages have been serious. Establishing transverse eco-compensation mechanisms becomes the key method to achieve sustainable use of water resources. Based on statistical and questionnaire data, this paper uses the Opportunity Costs Method and Willingness to Pay approach to establish a transverse eco-compensation standard calculation model for the Middle Route Project of the South- to-North Water Diversion. The results show that the upper and lower limits of the transverse eco-compensation standard for the Middle Route Project is $2.52 billion and $2.20 billion every year, respectively. However, the paying and receiving standards varied widely among different compensation payers and compensation receivers. Meanwhile, the significant factors influencing the paying willingness of the receiver area citizens were age, education level, average revenue per month, knowledge about the South-to-North Water Diversion Project and recognition of the importance of eco-environmental integrity. This study began with a theoretical analysis, then analysed related problems related to calculating transverse eco-compensation standards for the Middle Route Project of the South-to-North Water Diversion by an empirical study. This empirical study helps to establish effective transverse eco-compensation mechanisma and promotea the development of effective policies and legislation. 相似文献