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21.
Aharon Kellerman 《The Professional geographer》2013,65(4):538-546
This article attempts to explore the spatial dimension of Maslow's theory on the hierarchy of human needs, in light of the growing role of virtual space via the Internet in the contemporary information age. Generally speaking, virtual space constitutes a space for the gratification of human needs, side by side with physical space. Its role, as compared to physical space, grows along the hierarchy of human needs: physiology, safety, love and belonging, esteem, and self-actualization. Thus, its role for the gratification of physiological needs is complementary, whereas its role for self-actualization is significant. The growing role of virtual space has evolved into an equivalent hierarchical relationship with physical space: complementarity, competition, substitution, escape, and, potentially also exclusivity. Escape from physical to virtual space, as both need and relationship, has been brought about by social networking, being similar to the physical escape offered by tourism. It does not seem real to foresee that virtual space will offer exclusive fulfillment of as of yet unforeseen new human needs. 相似文献
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地震尺度下碳酸盐岩储层的岩石物理建模方法(英文) 总被引:3,自引:3,他引:0
碳酸盐岩油藏的强非均质性以及孔隙结构的复杂性,使得作为连接油藏参数与地震参数重要桥梁的岩石物理模型,以及作为油藏预测和定量表征最有效工具的流体替换成为岩石物理建模的难点与重点。在碳酸盐岩储层复杂孔隙结构与地震尺度下碳酸盐岩储层非均质性分析基础上,研究采用岩石网格化方法,将地震尺度下非均质碳酸盐岩储层岩石划分为具有独立岩石参数的均质岩石子体,根据岩石孔隙成因与结构特征采用不同岩石物理模型分步计算岩石子块干岩石弹性模量,并根据不同孔隙连通性进行流体替换,计算饱和不同流体岩石弹性模量。基于计算的岩石子块弹性模量,采用Hashin-Shtrikman-Walpole弹性边界计算理论方法实现地震尺度下碳酸盐岩储层弹性参数计算。通过对含有不同类型孔隙组合碳酸盐岩储层模型的弹性模量进行计算与分析,明确不同孔隙对岩石弹性参数的影响特征,模拟分析结果与实际资料认识一致。 相似文献
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利用空间矢量方法推导出了椭球面上只与起止点地理坐标有关的大椭圆航线方程,代入4种常用海图投影的正解公式,得到不同投影平面上的大椭圆参数方程;利用上述参数方程进而推导出了不同投影面上大椭圆航线的曲率与曲率半径公式。选取伦敦到纽约的大椭圆航线为例,通过绘制不同投影面上的大椭圆航线并分析其曲率、曲率半径变化曲线可知,大椭圆航线在日晷投影上的表象为曲率处处为0的直线,而在其他投影面上的表象为曲率较小但不断变化的曲线。利用推导的曲率半径公式可以计算各类大椭圆航线上任意位置的“代曲直距”,方便在不同比例尺的海图上对大椭圆航线进行量测和绘制,提高作图效率。 相似文献
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Although there is no assumption of pore geometry in derivation of Gassmann's equation, the pore geometry is in close relation with hygroscopic water content and pore fluid communication between the micropores and the macropores. The hygroscopic water content in common reservoir rocks is small, and its effect on elastic properties is ignored in the Gassmann theory. However, the volume of hygroscopic water can be significant in shaly rocks or rocks made of fine particles; therefore, its effect on the elastic properties may be important. If the pore fluids in microspores cannot reach pressure equilibrium with the macropore system, assumption of the Gassmann theory is violated. Therefore, due to pore structure complexity, there may be a significant part of the pore fluids that do not satisfy the assumption of the Gassmann theory. We recommend that this part of pore fluids be accounted for within the solid rock frame and effective porosity be used in Gassmann's equation for fluid substitution. Integrated study of ultrasonic laboratory measurement data, petrographic data, mercury injection capillary pressure data, and nuclear magnetic resonance T2 data confirms rationality of using effective porosity for Gassmann fluid substitution. The effective porosity for Gassmann's equation should be frequency dependent. Knowing the pore geometry, if an empirical correlation between frequency and the threshold pore‐throat radius or nuclear magnetic resonance T2 could be set up, Gassmann's equation can be applicable to data measured at different frequencies. Without information of the pore geometry, the irreducible water saturation can be used to estimate the effective porosity. 相似文献
27.
The thermal expansion of gehlenite, Ca2Al[AlSiO7], (up to T=830 K), TbCaAl[Al2O7] (up to T=1,100 K) and SmCaAl[Al2O7] (up to T=1,024 K) has been determined. All compounds are of the melilite structure type with space group
Thermal expansion data was obtained from in situ X-ray powder diffraction experiments in-house and at HASYLAB at the Deutsches Elektronen Synchrotron (DESY) in Hamburg (Germany). The thermal expansion coefficients for gehlenite were found to be: α1=7.2(4)×10−6 K−1+3.6(7)×10−9ΔT K−2 and α3=15.0(1)×10−6 K−1. For TbCaAl[Al2O7] the respective values are: α1=7.0(2)×10−6 K−1+2.0(2)×10−9ΔT K−2 and α3=8.5(2)×10−6 K−1+2.0(3)×10−9ΔT K−2, and the thermal expansion coefficients for SmCaAl[Al2O7] are: α1=6.9(2)× 10−6 K−1+1.7(2)×10−9ΔT K−2 and α3=9.344(5)×10−6 K−1. The expansion-mechanisms of the three compounds are explained in terms of structural trends obtained from Rietveld refinements
of the crystal structures of the compounds against the powder diffraction patterns. No structural phase transitions have been
observed. While gehlenite behaves like a ’proper’ layer structure, the aluminates show increased framework structure behaviour.
This is most probably explained by stronger coulombic interactions between the tetrahedral conformation and the layer-bridging
cations due to the coupled substitution (Ca2++Si4+)-(Ln
3++Al3+) in the melilite-type structure.
Electronic Supplementary Material Supplementary material is available for this article at 相似文献
28.
有机质对S1nm锰矿相金属阳离子交换能力的影响 总被引:3,自引:0,他引:3
大洋多金属结核问题长期以来一直受到人们的关注[1~3].大量的研究结果表明,多金属结核中最有经济价值的铜、钴、镍等有价金属元素,主要赋存于仅占整个结核约15%锰矿相中.我们曾对人工合成1 nm锰矿相(synthetic 1nm manganate,以下简称S1nm锰矿相)金属阳离子交换能力作过初步探讨[4,5],研究表明,Cu2+,Co2+,Ni2+,Zn2+等与S1nm锰矿相具有强烈的阳离子交换能力,证明了多金属结核成矿后期的离子交换是铜、钴、镍、锌等有价金属元素进入多金属结核的重要途径之一. 相似文献
29.
应用图论理论,直接根据控制网平差的基于测站的网点信息和观测值文件,提出了最小独立闭合环自动生成的逐步回代法和附合导线自动生成的组合法,并编程予以实现。最后用实例验证了算法的正确性和用之进行观测值质量检核的有效性。 相似文献
30.