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251.
简要介绍了地磁台链观测在极光带电集流、赤道电集流、中低纬度大尺度电流体系、太阳风-磁层-电离层-高层大气能量耦合、高-中-低纬的扰动传输、磁层中磁流体波的传播、主磁常荚期变化等研究中的应用,综述了地磁台链观测在地磁与空间物理研究中的物理基础和研究现状,着重回顾了IMS 期间6个高纬子午台链的观测研究,总结了中国地磁台链研究的初步结果.中国所处的独特地理位置和广阔的经纬度展布提供了建立全球唯一的闭合子午圈台链的可能性.中国台链向北与俄罗斯东西伯利亚地磁台相连,一直延伸到北极光带,向南与菲律宾、印尼、澳大利亚台站相连直达南极区中山站,通过南极与对面子午线上的长城站相连,并与南美、北美台站构成一条闭合的子午圈台链.可以预料,这条台链的观测资料将为地磁与高空物理研究提供宝贵的资料,对研究日地整体行为将会有重要意义. 相似文献
252.
THE DISPERSION RELATION, OF EARTH''S ELECTROMAGNETIC RESPONSE FUNCTIONS AND THE JOINT INVERSION OF DATA 下载免费PDF全文
On the basis of the dispersion relations of MT field, the necessity and applied prospects of the joint inversions using a pair of MT response functions which are correlative with the dispersion relations, are infered. A filter coefficient algorithm is made, with which the corresponding impedance phase data can be estimated using a set of apparent resistivities. The tests for the observed MT data show that when comparing the impedance phase estimated using the dispersion relation with the ob served phase, it can be checked whether the dispersion relation between observed apparent resistivity and phase data is satisfied or not, and that the use of the phase data corrected using the dispersion relation in the joint inversion is advantageous to obtain more confident results. It is shown that joint inversions are more advantageous than single parameter inversions, and that in the most case the joint inversion using the apparent resistivities of impedance real and imaginary parts is more advantageous than the jointinversion using the normal apparent resistivity and impedance phase. The existence of the dipersion relations between the ratio apparent resistivity and corresponding impedance phase of the orthogonal electric and magnetic field horizontal Components in the frequency EM sounding with horizontal electric dipole(FEMS) are discussed, the better effect of the joint inversion using the pair of EM response functions is obtained. The problems on the one-dimensional joint inversion for the MT and FEMS apparent resistivities, for which the observed frequency bands partly overlape each other, are studied. It is shown that this joint inversion is applicable and effective:the joint inversions of the practical data for two kinds of EM methods at two sites give the results well corresponding to the drilling data. The simulated MT inversions for the data of two kinds of EM methods are made, and more confident results also are obtained. 相似文献
253.
本文以苏18井为例介绍了自流井泄漏的处理技术与井口动力参数的试验结果,采用钻也漏仪确定泄漏部位,内衬套管对环状间隙灌浆的堵漏技术,效果良好。采用不同泄水孔断面积对井口水动力参数进行了系列观测试验,对试验结果了分析,并推导了各参量间的函数关系,两者相当吻合,可以互相印证。 相似文献
254.
Comparative performance of indicator algorithms for modeling conditional probability distribution functions 总被引:1,自引:0,他引:1
P. Goovaerts 《Mathematical Geology》1994,26(3):389-411
This paper compares the performance of four algorithms (full indicator cokriging. adjacent cutoffs indicator cokriging, multiple indicator kriging, median indicator kriging) for modeling conditional cumulative distribution functions (ccdf).The latter three algorithms are approximations to the theoretically better full indicator cokriging in the sense that they disregard cross-covariances between some indicator variables or they consider that all covariances are proportional to the same function. Comparative performance is assessed using a reference soil data set that includes 2649 locations at which both topsoil copper and cobalt were measured. For all practical purposes, indicator cokriging does not perform better than the other simpler algorithms which involve less variogram modeling effort and smaller computational cost. Furthermore, the number of order relation deviations is found to be higher for cokriging algorithms, especially when constraints on the kriging weights are applied. 相似文献
255.
256.
M K Panigrahi A Mookherjee G V C Pantulu K Gopalan 《Journal of Earth System Science》1993,102(2):399-413
On the basis of field relations, petrography and chemistry, three types of granitoids are recognized at Malanjkhand in and
around the copper deposit over an area of about 200 km2. These are (i) a fine grained ‘leucogranite’ of restricted occurrence in the surrounding area (Gr-I); (ii) coarse-grained,
grey in most parts, gneissose granitoid of regional extension (Gr-II); and (iii) the pink-feldspar bearing massive type hosting
the mineralization with occasional representatives in the surrounding country (Gr-III). Gr-I comes out as a distinct entity
on the basis of cross-cutting relation and mineralogical and chemical composition, the Rb-Sr whole rock isochron also giving
a younger age than the other two groups irrespective of the regression model used. Gr-II comes out as the oldest unit but
its age relationship with Gr-III cannot be established unequivocally. An uncorrelated error regression model establishes the
age relationship as Gr-I<Gr-III<Gr-II, whereas a two-error regression model establishes temporal closeness between Gr-II and
III.
The term ‘granitoids’ is being used broadly to include rocks ranging in composition from alkali-granite to tonalite. 相似文献
257.
坪定砷金矿床氧化带的表生地球化学作用 总被引:2,自引:0,他引:2
坪定砷金矿床的浅部矿体在表生地球化学条件下,经受了氧化—淋滤与次生富集两种相互矛盾的地质作用。金和砷总的趋势是淋失,但在某些部位也产生了一定的次生富集作用。经过表生作用以后,矿体中元素之间的关系也发生了显著变化。但由于本区的剥蚀速率较快,浅部矿石不断更新;赋矿地层的岩性以泥板岩为主,构造裂隙不很发育,地下水的泄水作用受阻,第四系冰碛层的覆盖也对矿体起到一定的保护作用,故总的看来,现存于氧化带的矿石,其氧化程度并不是很高。 相似文献
258.
A Simplified Technique for Simulating Wide-band Strong Ground Motion for Two Recent Himalayan Earthquakes 总被引:1,自引:0,他引:1
A simplified technique for simulation of wide-band strong motion based on simple regression relations and Empirical Greens Function (EGF) technique by Irikura (1986) is presented in this paper. The method uses the acceleration envelope as a shaping window for a filtered white Gaussian noise, to get the synthetic accelerogram from each subfault. Correction factors for slip of large and small events and transmission factors at each boundary of different layers are included in this synthetic accelerogram. The synthetic accelerogram obtained from each subfault is used as the Greens function to get resultant records. Simulations are made for the confirmed models of the Uttarkashi and the Chamoli earthquakes at a number of stations to get wide-band strong ground motion. The comparison of synthetic with the observed records over a wide range of frequencies for two different Himalayan earthquakes establishes the efficacy of the present technique. 相似文献
259.
松辽盆地北部源岩和盖层的时空匹配关系及其对天然气聚集与分布的控制 总被引:9,自引:5,他引:4
通过对松辽盆地北部5套泥岩盖层和3套气源岩空间分布面积的比较,以及对盖层封闭能力形成时期与气源岩大量排烃期的比较,研究了松辽盆地北部5套泥岩盖层与3套气源岩之间的时间和空间匹配关系及其对天然气聚集程度的控制作用,指出扶杨油层和萨、葡、高油层是松辽盆地北部天然气聚集与分布的有利层位。扶杨油层天然气富集程度在空间上存在差异,大庆长垣以东地区好于大庆长垣以西地区。萨、葡、高油层和黑帝庙油层的天然气富集程度在空间上存在差异,大庆长垣以西地区好于大庆长垣以东地区。 相似文献
260.
利用灰色关联分析方法,从经济生产、社会生产和生态生产角度出发对西昌市社会经济活动与生态环境之间的关系进行了量化研究。研究表明:农业产业的活动是影响水土流失的主要因素,换句话说,调控农业产业经济活动是生态环境维护的有效途径。生态生产、经济生产和社会生产之间存在明显的作用关系,这种作用关系不外乎表现在正作用和负作用两个方面,生态与经济的协调很大程度上依赖于对以上三类要素的合理调节。事实上, 就是利用以上三类生产要素的可塑性,通过产业经济活动的调控,弱化或消除产业与生态的矛盾,积极发展生态产业,这对西昌如此,对其他地区仍具有普遍意义。 相似文献