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31.
Résumé L'étude des bassins côtiers de Sfax et de la Djeffara de Gabès Nord, basée sur l'interprétation des données hydrochimiques (éléments majeurs) et isotopiques (18O, 2H et 14C), a permis une meilleure compréhension du fonctionnement hydrodynamique de l'aquifère Miocène le long de la frange côtière. En effet, d'après les données géochimiques, apparaît la présence de deux types de faciès chimiques: chloruré sodique dans le bassin de Sfax et mixte à chloruré sodique dans le bassin de Gabès Nord. Cette transition d'un faciès à un autre souligne la variabilité des origines de minéralisation des eaux. L'utilisation des outils isotopiques a permis l'identification d'une eau relativement ancienne à l'exception de quelques poches de recharge récente matérialisées à partir du relief de Zemlet El Beida en amont du bassin de Gabès Nord. Ceci a été vérifié par les fortes activités en14C des eaux dans cette région. Par conséquent, on peut noter que le passage du Sud au Nord le long de la côte est marqué par une grande variation latérale de lithologie et d'épaisseur de la formation aquifère, soulignant ainsi l'indépendance de chacun des deux réservoirs de Sfax et de la Djeffara de Gabès en absence de toute continuité hydrodynamique entre les deux bassins. Editeur Z.W. Kundzewicz; Editeur associé S. Faye Citation Ben Cheikh, N., Zouari, K., et Abidi, B., 2012. Application des outils chimiques et isotopiques à l'étude de la relation hydrodynamique entre les aquifères profonds de Sfax et de la Djeffara de Gabès Nord (Sud-Est tunisien). Hydrological Sciences Journal, 57 (8), 1662–1671. 相似文献
32.
In this paper we describe two different methods to expand the second term of the planetary Hamiltonian function. The Jacobi
system of coordinates is adopted leading to a unique evaluation of the Hamiltonian. Previous analytical or semi-analytical
planetary theories suffer from the drawback of computing the perturbation function for each planet, which is quite cumbersome.
The inclinations of planets are referred to a common fixed plane and the longitudes to a common origin. This is necessary
when we deal with n > 2 planets. The treatment is straightforward, and no complexities appear throughout the analysis.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
33.
Osman M. Kamel 《Earth, Moon, and Planets》1983,28(3):221-245
In this part we determine the value ofS
1,
and
in terms of the canonical variables of H. Poincaré. A complete solution of the auxiliary system of equations generated by the Hamiltonian
is presented. 相似文献
34.
Mohamed W. Ali-Bik Hussein I. M. Metwally Mohamed G. Kamel Ashraf M. A. Wali 《Environmental Earth Sciences》2011,62(1):151-159
Biogenic gypsum in the form of microbialite and potential domal stromatolite as well as endoevaporitic dolomite are deposited
in a perennial saline basin characterized by microbial bloom. Deposition environment, mode of occurrence, and microscopic
investigation including SEM of these precipitates are discussed in conjunction with XRD, XRF, and FTIR data. Combined effects
of salinity gradient and the wind action on the maturity of gypsum outcrop are evident. A characteristic multi-color vertical
gypsum profile reflects steep gradient of oxi-anoxic microenvironments and encodes diverse seasonal microbial communities.
Direct impact of microbial signature in gypsum crystal habit is conspicuous. Endoevaporitic authigenic dolomite is recorded
in specific horizons in interstices of selenite layers. 相似文献
35.
Recharge mode and mineralization of groundwater in a semi-arid region: Sidi Bouzid plain (central Tunisia) 总被引:1,自引:1,他引:0
Hichem Yangui Kamel Zouari Rim Trabelsi Kazimierz Rozanski 《Environmental Earth Sciences》2011,63(5):969-979
Groundwater is the most important source of water supply in Sidi Bouzid plain located in central Tunisia. Proper understanding
of the geochemical evolution of groundwater is important for sustainable development of water resources in this region. A
hydrogeochemical survey was conducted on the Mio–Plio–Quaternary aquifer system using stable isotopes, radiocarbon, tritium
and major elements, in order to evaluate the groundwater chemistry patterns and the main mineralization processes occurring
in this system. The chemical data indicate that dissolution of evaporate minerals and evaporation are the main processes controlling
groundwater mineralization. The isotopic data show that groundwater in the study area is a mixture of recent shallow waters
located upstream and along Wadi Al Fakka bed and paleowaters located towards plain limits and discharge areas. Low 3H and 14C contents are observed in major part of the plain indicating that recharge of the aquifer occurs mainly through direct infiltration
at Wadi Al Fakka while there is no evidence of significant recharge in major part of the plain and mountains piedmonts. 相似文献
36.
Christophe Nkem Kamel Hammami Idriss Yacoub Halalaw Luc Calvin Owono Owono Nejm-Eddine Jaidane 《Astrophysics and Space Science》2014,349(1):171-179
We report on ab initio coupled-cluster calculations of the interaction potential energy surface for the HCNH+–He complex. The aug-cc-pVTZ Gaussian basis, to which is added a set of bond functions placed at mid-distance between HCNH+ center of mass and He atom is used. The HCNH+ bonds length are set to their values at the equilibrium geometry, i.e., r e [HC]=1.0780 Å, r e [CN]=1.1339 Å and r e [NH]=1.0126 Å. The interaction energy presents a global minimum located $266.9~\mathrm{cm^{-1}}$ below the HCNH+–He dissociation limit. Using the interaction potential obtained, we have computed rotational excitation cross sections in the close-coupling approach and downward rate coefficients at low temperature (T≤120 K). It is expected that the data worked out in this study may be beneficial for further astrophysical investigations as well as laboratory experiments. 相似文献
37.
The secular terms of the first-order planetary Hamiltonian is determined, by two methods, in terms of the variables of H. Poincaré, neglecting powers higher than the second in the eccentricity-inclination. 相似文献
38.
Osman M. Kamel 《Earth, Moon, and Planets》1990,49(3):259-267
We construct the outline of a third order secular theory for the four major planets. We apply the Hori-Lie technique to solve the problem. We take into consideration both parts of the perturbing function. Our canonical variables are those of H. Poincaré. Our periodic terms are the only 2:5 and 1:2 critical terms of J-S and U-N respectively. Terms of degree higher than the second in the Poincaré canonical variables H, K, P, Q are neglected. 相似文献
39.
Mathematical Geosciences - Natural draft dry cooling towers (NDDCTs) are a type of cooling technology used in thermal power plants, including geothermal power plants. Interest from industry in this... 相似文献
40.
Quantifying regional groundwater flow between Continental Intercalaire and Djeffara aquifers in southern Tunisia using isotope methods 总被引:4,自引:0,他引:4
Large-scale interaction between the Continental Intercalaire and the Djeffara aquifer systems in the southeast of Tunisia
has been investigated with the aid of chemical and isotopic tracers. Two distinct groundwater types have been identified:
(1) the Continental Intercalaire groundwater characterized by elevated temperatures (50–61.4°C), low δ18O (−8.4 to−7.87) and δ2H (−67.2 to−59) values and negligible radiocarbon content, both testifying its great age dating from the late Pleistocene
period, and (2) the Djeffara groundwater with distinctly heavier isotopic composition (δ18O = −8.31 to −5.80, δ2H = −65.9 to −31.9). The Djeffara groundwaters reveal a distinct changes of physico-chemical and isotopic parameters near
El Hamma Faults in the northwestern part of the Djeffara basin. These changes could possibly be explained by a vertical leakage
from the Continental Intercalaire aquifer through El Hamma Faults. The mixing proportions inferred from stable isotope mass
balance prove that the contribution of the Continental Intercalaire to the recharge of Djeffara aquifer is very significant
and may reach 100% in the El Hamma region and in the northern part of Gabes. Isotope tracers strongly suggest that recent
recharge to the Djeffara aquifer system is very limited. Its current yield, particularly in its central and northern parts
can be maintained only thanks to large-scale underground inflow from the Continental Intercalaire aquifer system, which carries
late Pleistocene palaeowater. Consequently, current exploitation of groundwater resources of the Djeffara aquifer has non-sustainable
character. 相似文献