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661.
阐述了一种新型机载激光影像制图系统的基本原理、技术结构、数据处理及发展前景。机载激光影像制图系统是视距测量原理在机载遥感技术系统中的实现,“高效率”和“定位”、“定性”能力增强是其主要特点,并将成为高动态资源环境监测的新型技术系统。 相似文献
662.
校园空气微生物污染状况及时空分布特征 总被引:2,自引:0,他引:2
通过定点取样研究校园空气微生物浓度及时空分布规律.并采用有关标准,评价校园空气微生物污染状况.监测结果表明: (1)室内监测点中,教学区全部合格;宿舍在春季和秋季合格,冬季和夏季不合格;餐厅中西苑餐厅全年均不合格.室外监测点中复合绿地和道路全年处于污染状况. (2)校园各功能区中,空气微生物浓度室内明显低于室外(p<0.05);在空气微生物总浓度中,空气细菌的含量占绝大多数(平均占88.99%). (3)校园各功能区空气细菌和真菌浓度年季变化特征显著.空气细菌浓度在春季最高,空气真菌浓度夏、秋季最高,冬、春季最低. (4)针对监测结果提出了相应的环境卫生的管理措施. 相似文献
663.
通过航空物探(电、磁)综合站在已知铜钼多金属矿床上的飞行测量结果,根据从已知到未知的原则,建立航空物探(电、磁)综合测量在草原、森林、沼泽区寻找斑岩型铜多金属矿的找矿模式。根据此试验模式圈定的航空物探异常,在进行地面查证时取得很好的地质效果。 相似文献
664.
柴东地区航放异常成因及其找矿意义 总被引:1,自引:0,他引:1
1997年在柴达木盆地东部(柴东地区)五道梁及北霍布逊湖地区发现了两片共7处航放异常。本从基础地质条件出发,分析、研究了柴东地区的区域地下水动力条件,对航放异常区的放射性水地球化学特征进行了分析,重点解剖了五道梁地区航放异常。从水地质角度探讨了航放异常成因,认为其反映了深部铀成矿信息,进而指出柴东地区有利于形成层间氧化带砂岩型铀矿化,值得进一步工作。 相似文献
665.
机载激光测深海面扫描轨迹计算与分析 总被引:1,自引:0,他引:1
介绍了机载激光测控技术的椭圆扫描原理,推导出在椭圆扫描方式下计算激光海面扫描轨迹的数学模型,并进行了编程模拟运算,绘图和扫描特征分析。 相似文献
666.
M.-L. Airo 《Surveys in Geophysics》2002,23(4):273-302
In Precambrian terrains all regional and most localintensive magnetic anomalies areproduced by magnetite. Monoclinic pyrrhotite isresponsible for some local, but oftenintensive, magnetic anomaly patterns. Both magnetiteand pyrrhotite are affected byhydrothermal alteration processes in various ways,resulting in changes either inabundance or in grain fabric. These changes arerecorded in the magnetic properties ofthe altered rock units and reflected in theiraeromagnetic signatures. Hydrothermalalteration in deformed bedrock zones is commonlycontrolled by structural or tectonicfeatures. Regional high-resolution aerogeophysicalsurveys can be utilized, in bothregional and detailed investigations, to map theoverall geological and tectonic settingor to estimate local changes in magnetic mineralogyand the relative abundance ofradionuclides.Magnetite is most commonly destroyed in alterationprocesses, such as biotitization,carbonation, sulfidization and silicification. Theprogressive destruction of magnetitebegins at grain margins and results first in broken and cracked grain texture and smallergrain size, then progresses to total disappearanceof magnetite. Alteration in magnetite-bearing rock units may be recognized by decreasedmagnetic intensity and by thebroken, disrupted magnetic pattern. The abundance ofmonoclinic pyrrhotite isenhanced by reducing hydrothermal fluids, and typicalcrystal anisotropy is developeddue to tectonic stress.The relative contents of radioelements are changedin the same hydrothermal processesand partly for the same reasons as the ferrimagneticminerals. Potassic alteration oftenresults in elevated K radiation particularly formafic rocks, and then anomalous K/Thratios along local shear or fracture zones may beindicative of gold-bearingmineralization. On the other hand, high U/Th ratioswithin metasedimentary units maypoint out prospects for sulphidization. Althoughvariation of U/Th ratios largely reflectsthe environmental conditions during primarydiagenesis or a later deformational phase,mainly the decrease in Th radiation close tosulphide mineralization seems to beresponsible for the elevated U/Th ratios. 相似文献
667.
Airborne Shortwave Infrared Spectral Remote Sensing as a Direct Prospecting Method for Oil and Gas Resources 总被引:1,自引:0,他引:1
杨柏林 《中国地球化学学报》1994,13(2):156-164
The spectral characters of hydrocarbons in some oil-bearing strata and soil layers ouer oil and gas reservoirs in the Junggar Basin and northern Tarim Basin in Xinjng are compared with those of chemically pure hydrocarbons.The hydrocarbons are characterized by the bi-absorption at 2310nm and 2350nm.Hydrocarbon and radioactive anomalies in oil and gas terrains are found much more widespread than carbonate alterations.Based on the spectra of heavy hydrocarbons related to oil between 2270nm and 2460nm and refined data treatme nt, remote sensing may hold encouraging promise as a directly prospecting technique for oil and gas resources. 相似文献
668.
To detect eddies, intensive surveys of the northeast South China Sea (SCS) (114°30′–121°30′ E, 17°–22°N) were conducted in
July 1998 during the international SCS Monsoon Experiment (SCSMEX), the U.S. Navy using Airborne Expendable Bathythermograph
and Conductivity-Temperature-Depth sensors (AXBT/AXCTD), and the Chinese Academy of Sciences using Acoustic Doppler Current
Profilers (ADCP). The hydrographic survey included 307 AXBT and 9 AXCTD stations, distributed uniformly throughout the survey
area. The ADCP survey had two sections. The velocity field inverted from the AXBT/AXCTD data and analyzed from the ADCP data
confirm the existence of a low salinity, cool-core cyclonic eddy located northwest of Luzon Island (i.e., the Northwest Luzon
Eddy). The radius of this eddy is approximately 150 km. The horizontal temperature gradient of the eddy increases with depth
from the surface to 100 m and then decreases with depth below 100 m. The cool core was evident from the surface to 300 m depth,
being 1°–2°C cooler inside the eddy than outside. The tangential velocity of the eddy is around 30–40 cm/s above 50 m and
decreases with depth. At 300 m depth, it becomes less than 5 cm/s.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
669.
670.
对利用小比例尺数码航摄资料进行控制,获取应用于城市规划设计前期1:1000地形图资料的方法进行探讨和实践,进行理论分析和实际应用结果分析,提出满足了我们规划用图的需要。这种方法可为今后一些局部地区急需用图,测绘作为借鉴。 相似文献