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361.
Kuleshevich L. V. Filippov M. M. Goltsin N. A. Krymsky R. Sh. Lokhov K. I. 《Lithology and Mineral Resources》2019,54(2):145-158
Lithology and Mineral Resources - The Maksovo shungite-bearing metasapropelite (maksovite) deposit is located in the eastern part of the Onega Basin that was initiated and formed in the... 相似文献
362.
Algorithm for recognizing Pc3 geomagnetic pulsations in 1-s data from INTERMAGNET equatorial observatories 总被引:1,自引:0,他引:1
N. R. Zelinskiy N. G. Kleimenova O. V. Kozyreva S. M. Agayan Sh. R. Bogoutdinov A. A. Soloviev 《Izvestiya Physics of the Solid Earth》2014,50(2):240-248
The methods are suggested for analyzing the data of three-component geomagnetic observations in order to automatically recognize time anomalies-pulsations in the geomagnetic field. These methods include preliminary bandpass filtering of the data, calculating the eigenvalues of the covariance matrix of magnetic components in a moving time window, computing the generalized variance of the eigenvalues (generalization is understood as raising to a power that is distinct from the traditional power of 2), averaging the variance, and identifying the time intervals marked by the presence of pulsations by the criterion of the averaged variance of eigenvalues to exceed a certain threshold specified by the fuzzy-logic methods. 相似文献
363.
Broodstock of Verasper moseri (Jordan and Gilbert) aged 3-4 years old were selected,and reinforced cultivation was conducted to promote maturation under controlled water temperature and photoperiod conditions.Fertilized eggs were obtained by artificial fertilization,and the development of embryos,larvae and juveniles was observed continuously.The results showed that the fertilized eggs of V.moseri were spherical,with transparent yolk and homogeneous bioplasm,and had no oil globule inside.The average diamete... 相似文献
364.
Vibrio anguillarum is an important bacterial pathogen of aquatic organisms and a significant problem in aquatic farming.The rapid detection and identification of V.anguillarum,and other pathogens that infect marine organisms,is crucial to effective disease management.In this study,we developed a loop-mediated amplification (LAMP) assay to detect V.anguillarum in an hour in a single tube without the need for thermal cycling.Conserved regions of the metalloproteinase (empA) gene of V.anguillarum served as the targets for primer design.A fragment of the empA gene was amplified at 65°C in the presence of the primer mixture and Bst DNA polymerase.In the optimized LAMP assay,6.7 pg of V.anguillarum DNA could be detected.Six strains of V.anguillarum and 17 strains of non-V.anguillarum bacteria were used in this study to evaluate the species specificity of the primers.The six V.anguillarum strains gave a positive result in the LAMP assay.This method was also validated in V.anguillarum-infected fish.This LAMP method is more sensitive than PCR in the detection of V.anguillarum and shows good species specificity.The LAMP assay is therefore an effective method for the quick detection of V.anguillarum both in the laboratory and in the field. 相似文献
365.
M. Saeedi Sh. Daneshvar A. R. Karbassi 《International Journal of Environmental Science and Technology》2004,1(2):135-140
Riverine sediments and suspended matters have been subjected to several bench scale tests for the evaluation of adsorption potential of heavy metals. For this purpose water, sediment and suspended particulate matters of Tadjan River (southern part of the Caspian Sea) were collected. In the vicinity of the river many polluting sources were recognized; for instance, pulp and paper mill, dairy factory and municipal sewage that can introduce various amounts of heavy metals into the river water. Bottom sediments and suspended particulate matters have been individually subjected to adsorption tests. The results of analysis showed that riverine bottom sediments have greater potential for adsorbing heavy metals than suspended matters. However the trend of adsorption in both sediments and suspended matters are similar. Maximum adsorption capacity of heavy metals (in terms of mg of metal per kg of sediments and suspended matters) by sediments and suspended matters are as: Sediments: Cu (2200)> Mn (2000)> Ni (1400)> Zn (320) Suspended matters: Cu (2100)> Ni (1500)> Mn (1200)> Zn (310) Further, results revealed that increasing concentration of metals would cause desorbing Cadmium from both sediments and suspended matters. 相似文献
366.
应用核磁共振测井资料评价储层孔隙结构的改进方法 总被引:1,自引:0,他引:1
通过对实验室压汞资料和核磁共振测量资料的对比分析,利用确定压汞孔径分布曲线孔径rc左右边界的方法确定核磁共振T2谱与孔喉半径rc的横向转换系数,利用改进二维分段等面积刻度方法确定其纵向转换系数,使得计算得到的伪毛管压力曲线与实验室压汞测量的毛管压力曲线基本一致。另外,对各种转换系数进行建模,实现在无实验室压汞资料情况下获得定量、连续、高精度的伪毛管压力曲线和孔隙结构参数。将研究成果用于复杂储层评价中,可进行储层分类和估算产能。 相似文献
367.
金蟾山金矿位于位于华北克拉通北缘成矿带中部,赤峰-开原深大断裂与平泉一八里罕大断裂交汇处,喀喇沁变质核杂岩北部,该区金矿点分布密集,金矿床众多,区内还有二道沟、大黑山、黄花沟等近 20 余处金矿床(点),是我国重要的金矿化集中区之一。金矿床主分布与岩浆、断裂构造关系密切,靠近断裂处矿化尤为集中。矿区分东西两条主矿带,矿化带长一般为数千米,宽可达数百米,而矿化带的矿体长一般为数十米至百余米,厚度1~3m左右,矿体多呈脉状、豆荚状、透镜状等。为研究该区深部和外围找矿前景,对该区与成矿关系密切的安家营子岩体及主要构造分析的基础上,结合岩石化学剖面测量、面积性激电测量及可控源音频大地电磁(CSAMT)剖面测量数据资料进行综合分析,从幔枝构造理论出发构建找矿模式,认为矿体深部和外围仍有一定的找矿潜力。 相似文献
368.
XIAO QiBin ZHAO GuoZe WANG JiJun ZHAN Yan CHEN XiaoBin TANG Ji CAI JunTao WAN ZhanSheng WANG LiFeng MA Wei & ZHANG JiHong Institute of Geology China Earthquake Administration Beijing China Earthquake Administration of Sh ong Province Jinan 《中国科学D辑(英文版)》2009,52(3):420-430
Because of the discovery of ultrahigh pressure metamorphic (UHPM) belt beneath the Sulu (Jiangsu Province-Shandong Province)
orogen, this area has become a focused subject of current geoscience, as it has a close relationship with the evolution of
the orogen and the neighboring North China craton. Probing the deep structure beneath this area would be of great significance
for the geological interpretation of this issue. In this study, we make an analysis of magnetotelluric (MT) data along a profile
across the Sulu orogen to provide evidence of deep structure below this region. The profile begins in west from the North
China block, extending in S129°E, across the Tan-Lu fault, Sulu UHPM zone, and Sulu high pressure metamorphic (HPM) zone,
and terminates in the Yangtze block in east. We use the nonlinear conjugate gradient method and TE-TM combined mode to perform
inversion and interpretation of the MT data, and obtain an electrical structure image above depth of 150 km along the profile.
It shows that the structure can be divided into seven sections in lateral direction, between which the electric boundaries
coincide well with the major faults, such as the Tan-Lu, Haizhou-Siyang, and Jiashan-Xiangshui faults. In vertical direction
the electrical structure can be subdivided into six layers of different resistivities. It is noted that there exist high-conductivity
areas in crust below the North China block and Yangtze block, while such a feature is not present beneath the Sulu orogen,
which is very different from the Dabie orogen. It is also observed that a fairly continuous zone of relatively low-resistivity
exists at depths of 50–90 km of the electrical structure image, which is presumably a weak zone in the uppermost mantle. Just
below this low-resistivity zone are the relatively high- resistivity layer of the North China block, relatively low-resistivity
layer of the Sulu orogen, and relatively high-resistivity layer of the Yangtze block, all in the shallow upper mantle, respectively.
From the whole 2D electrical structure image, there is no abnormally low-resistivity layer in the shallow upper mantle beneath
the Sulu orogen and neighboring areas, indicating that no hot asthenoshperic material associated with lithospheric thinning
exists at present.
Supported by National Natural Science Foundation of China (Grant No. 40534023) and Director Foundation of Institute of Geology,
China Earthquake Administration (Grant No. DF-IGCEA-0608-2-16) 相似文献
369.
Agayan S. M. Soloviev A. A. Bogoutdinov Sh. R. Nikolova Yu. I. 《Geomagnetism and Aeronomy》2019,59(3):359-367
Geomagnetism and Aeronomy - New mathematical constructions are developed for the regression smoothing of discrete time series defined on an irregular grid. The new method is used to study secular... 相似文献
370.
Konstantin V. Kholshevnikov Vakhit Sh. Shaidulin 《Celestial Mechanics and Dynamical Astronomy》2017,128(1):75-94
The main form of the representation of a gravitational potential V for a celestial body T in outer space is the Laplace series in solid spherical harmonics \((R/r)^{n+1}Y_n(\theta ,\lambda )\) with R being the radius of the enveloping T sphere. The surface harmonic \(Y_n\) satisfies the inequality The angular brackets mark the maximum of a function’s modulus over a unit sphere. For bodies with an irregular structure \(\sigma = 5/2\), and this value cannot be increased generally. However, a class of irregular bodies (smooth bodies with peaked mountains) has been found recently in which \(\sigma = 3\). In this paper, we will prove the exactness of this estimate, showing that a body belonging to the above class does exist and for it.
相似文献
$$\begin{aligned} \langle Y_n\rangle < Cn^{-\sigma }. \end{aligned}$$
$$\begin{aligned} 0<\varlimsup n^3\langle Y_n\rangle <\infty \end{aligned}$$