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21.
以蒙脱石为初始材料,通过水热实验模拟在不同温度压力条件下蒙脱石的伊利石化过程。利用X射线粉末衍射及X射线荧光光谱、红外光谱和扫描电镜等方法对样品的矿物物相、化学成分、晶体结构与微观形貌等进行分析,其结果表明:(1)蒙脱石至伊利石的转化受温度和压力条件的控制;(2)随着温度和压力的增高,蒙脱石伊利石化沿着蒙脱石-无序伊蒙混层-有序伊蒙混层-伊利石的转化序列进行转化;(3)水热实验模拟表明蒙脱石至伊利石的转化以溶解重结晶机制为主。实验结果不仅有助于了解埋藏与低级变质作用中的蒙脱石伊利石化过程,同时为研究断层活动所致断层泥中黏土矿物的转化及反演断层形成时温度压力条件提供基本参数。 相似文献
22.
Alicja Wudarska Ewa Saby Michael Wiedenbeck Jaime D. Barnes Magali Bonifacie Neil C. Sturchio Grard Bardoux Frdric Couffignal Johannes Glodny Linnea Heraty Timm John Christof Kusebauch Sathish Mayanna Franziska D. H. Wilke Ewa Deput 《Geostandards and Geoanalytical Research》2021,45(1):121-142
Here we report on a set of six apatite reference materials (chlorapatites MGMH#133648, TUBAF#38 and fluorapatites MGMH#128441A, TUBAF#37, 40, 50) which we have characterised for their chlorine isotope ratios; these RMs span a range of Cl mass fractions within the apatite Ca10(PO4)6(F,Cl,OH)2 solid solution series. Numerous apatite specimens, obtained from mineralogical collections, were initially screened for 37Cl/35Cl homogeneity using SIMS followed by δ37Cl characterisation by gas source mass spectrometry using both dual‐inlet and continuous‐flow modes. We also report major and key trace element compositions as determined by EPMA. The repeatability of our SIMS results was better than ± 0.10‰ (1s) for the five samples with > 0.5 % m/m Cl and ± 0.19‰ (1s) for the low Cl abundance material (0.27% m/m). We also observed a small, but significant crystal orientation effect of 0.38‰ between the mean 37Cl/35Cl ratios measured on three oriented apatite fragments. Furthermore, the results of GS‐IRMS analyses show small but systematic offset of δ37ClSMOC values between the three laboratories. Nonetheless, all studied samples have comparable chlorine isotope compositions, with mean 103δ37ClSMOC values between +0.09 and +0.42 and in all cases with 1s ≤ ± 0.25. 相似文献
23.
24.
LIU Yan DENG Jun LI Guowu SHI Guanghai State Key Laboratory of Geological Processes Mineral Resources China University of Geosciences Beijing Key Laboratory of Lithosphere Tectonics Lithoprobing Technology of the Ministry of Education China University of Geosciences Beijing Laboratory of Single-Crystal X-Ray Diffraction China University of Geosciences Beijing 《《地质学报》英文版》2007,81(1):61-67
1 Introduction Natural beryl is an accessory mineral mainly in pegmatite, partly in some highly diffractionated granite or metamorphic rocks, with the crystal shapes beingprismatic, or occasionally tabular. For tabular beryl found in pegmatite it is believed that the tabular configuration is connected with alkali metals (Bieus, 1960; Wang et al., 1981) and geneses of the tabular configuration have been reported before. In recent years, tabular beryl has been found in the Xuebaoding W-Sn-Be d… 相似文献
25.
High-silica granitoids record the formation and evolution of the continental crust. A new intrusive complex has been recognized among silicic volcanic rocks of the Weixi arc, Southwest China. The intrusions consist of granites, granitic porphyries, and granodiorites. Zircon U-Pb age data indicate that the Weixi granitoids formed at 248–240 Ma and were coeval with silicic volcanic rocks of the Weixi arc. The Weixi granitoids are enriched in Rb, Th, and U, depleted in Ba, Sr, Nb, Ta, and Ti, and have high light/heavy rare earth element ratios and slightly negative Eu anomalies. The Weixi granitoids have negative εNd(t) values (?9.8 to ?7.8) and negative zircon εHf(t) values (?12.02 to ?5.11). The geochemical and isotopic features suggest the Weixi granitoids were derived by partial melting of ancient crustal material. The Weixi granitoids and silicic volcanic rocks were derived from the same magma by crystal accumulation and melt extraction, respectively, and they record the formation of a continental arc in the central Sanjiang orogenic belt. 相似文献
26.
Chemical investigation of the ethanol extract of the marine green alga Chaetomorpha basiretorsa Setchell led to the isolation of a new sterol stigmast-4,28-dien-3α,6β-diol 1 in addition to the five known sterols of β-lawsaritol 2, saringosterol 3, 24-hydroperoxy-24-vinyl - cholesterol 4, β-stigmasterol 5, 29-hydroxystigmasta-5, 24 (28) -dien-3β-ol 6. Compounds were isolated by normal phase silica gel and Sephadex LH - 20 gel colum chromatography, reverse phase HPLC and recrystalization. Their structures were elucidated by spectroscopic methods including MS, IR 1D/2D NMR and X-ray analysis. Cytotoxicity of compounds was screened by using the standard MTF method. All these compounds were isolated from the green alga Chaetomorpha basiretorsa Setchell for the first time and they were inactive (50% inhibitory concentration was greater than 10 μg/cm^3) against KB, Bel -7402, PC - 3M, Ketr 3 and MCF-7 cell lines. 相似文献
27.
N-(2-hydroxy-1-naphthaldene)-4-aminoantipyrine has been synthesized. The structure is determined by X-ray diffraction method and elemental analysis. The crystal system belongs to orthorhombic space group P(2)2(1)2(1). The geometry has been ob-tained from the density functional theory (DFT) method and the B3LYP method employing the 6-31G* basis sets. The calculated results propose that the latter is close to the experimental data. The structural parameters from the theory are close to those of the crystal and the calculated total energy of coordination is -31677.172 eV. The energy of HOMO and LUMO and the energy gap are 5.179 eV, -1.603 eV and 3.577 eV, respectively. 相似文献
28.
Formation elements logging is a neutron gamma spectroscopy logging technique used to acquire the content of elements and minerals by recording the gamma ray produced by the reaction of neutron and elemental nucleus in the formation. It has a wide usage in discriminating complex lithology and evaluating unconventional reservoir. The Monte Carlo simulation model of formation elements logging tool is established in this paper, with which the effects of tool parameters including the material and length of the scintillation crystal and source spacing on logging responses are modeled. The results show that the energy response of LaBr_3: Ce crystal is better than others, and the detection efficiency increases with the crystal length but decrease with source spacing. The above results may be used as a reference for optimizing the tool structure design. 相似文献
29.
WU Daqing DIAO Guiyi YUAN Peng PENG Jinlian 《《地质学报》英文版》2006,80(2):192-199
The adsorption of pentachlorophenol (PCP) onto quartz, kaolinite, illite, montmorillonite and iron oxides has been investigated by batch equilibrium techniques. The pH-dependent isotherms are curves with peak values, the position of which is at about pH = 5-6 depending on the mineral species. Based on distribution of both speciation of surface hydroxyls on minerals and PCP in solution a surface reaction model involving surface complexation and surface electrostatic attraction is presented to fit the pH-dependent isotherms, and both reaction constants are calculated. The results show that on quartz and phyllosilicate minerals the predominant adsorption reaction is surface complexation, meanwhile both of surface electrostatic attraction and surface complexation are involved on the iron oxide minerals. The reaction constants of surface electrostatic adsorption are usually one to three orders in magnitude, larger than that of surface complexation. The concentration-dependent isotherms can be well fitted by Langmnir equation with the correlation coefficient R〉0.93 for kaolinite and iron oxides. The maximum adsorption is found in the order: hematite 〉 lepidocrocite 〉 goethite 〉 kaolinite 〉 quartz 〉 montmorillonite ≈ illite, which can be interpreted by consideration of both reaction mechanism and surface hydroxyl density. The significant adsorption of PCP onto mineral surfaces suggests that clay and iron oxide minerals will play an important role as HIOCs are adsorbed in laterite or latertoid soil, which is widespread in South China. 相似文献
30.