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341.
中国城市(包括辖县)的工业职能分类——理论、方法和结果 总被引:18,自引:0,他引:18
在城市发展的经济基础理论的指导下,作者提出城市工业职能的概念包括城市的专业化部门、职能强度和职能规模三个要素。城市工业职能分类就是按照上述三要素的相似性和差异性对城市进行分类。本研究曾采用主因素分析、聚类分析和纳尔逊的统计分析等多种方法。最后以沃德误差法的聚类分析结果作为分类的基础,稍加修正,并以纳尔逊法分析结果作补充。中国1984年的295个城市被分成三个大类、十九个亚类和五十四个职能组。 相似文献
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FOREST C.GARNER MARTIN A.STAPANIAN KIRK E.FITZGERALD Lockheed Engineering Sciences Co. E.Flamingo R Las Vegas NV U.S.A. 《地理学报(英文版)》1991,(3)
Multivariate outliers in environmental data sets are often caused by atypical measurement error in a singlevariable.From a quality assurance perspective it is important to identify these variables efficiently so thatcorrective actions may be performed.We demonstrate a procedure for using two multivariate tests toidentify which variable‘caused’each outlier.The procedure is tested with simulated data sets that havethe same correlation structure as selected water chemistry variables from a survey of lakes in the WesternUnited States.The success rates are evaluated for three of the variables for sample sizes of 50 and 100,significance levels of 0.01 and 0.05 and various amounts of mean shift.The procedure works best forhighly correlated variables. 相似文献
345.
ROBERT R.MEGLEN Department of Chemistry Laboratory for Chemometrics University of Colorado at Denver PO Box Denver CO - U.S.A. 《地理学报(英文版)》1991,(3)
Principal component analysis is used to examine large multivariate databases.The graphical approachto exploratory data analysis is described and illustrated with a single example of chemical compositiondata obtained on environmental dust particles.While the graphical approach to exploratory data analysishas certain advantages over the numerical procedures,the empirical approach described here should beviewed as complementary to the more robust treatments that statistical methodologies afford. 相似文献
346.
<正> 酸性化合物总是存在于碳氢化合物中,其含量从百分之一到百分之几十。一方面,它们是讨厌的杂质(特别是H_2S),给勘探和野外工作带来很大麻烦;另一方面,它们又可能是难得的原料来源。由于在苏联几个地区——里海凹陷、Amu-Darya陆槽和西西伯利亚地台——发现了含 相似文献
347.
During summer Monex-79, a variety of observing systems viz. research ships, research aircrafts, constant pressure balloons and geostationary satellite etc. were deployed, besides the regular conventional observations. The purpose of these additional systems was to make the best possible data for the studies on various aspects of monsoon circulation. The present study is aimed at the construction of vertical wind profile using cloud motion vectors obtained from GOES (I-O) satellite and to examine whether the constructed wind profiles improves the representation of the monsoon system, flow pattern etc. in the objective analysis. For this purpose, climatological normals of the wind field are considered as the initial guess and the objective analyses of the wind field are made with, first using only data from conventional observations over land areas, subsequently including the constructed winds from cloud motion vectors. These analyses are then compared with the standard analyses of wind field obtained fro 相似文献
348.
Slight perturbations of the oceanic DOC by addition of oxalic acid, tryptophan, and sodium humate did not affect the magnesium content of spontaneously precipitated Mg-calcites. However, the copresence of spontaneously precipitated aragonite and of Mg-calcite as a function of the initial degree of supersaturation was changed by the dissolved organic matter. Times of nucleation for carbonates was affected by organic matter at low organic concentrations because of coating and at high concentrations due to complexation. 相似文献
349.
今年一月,英国地理学家在爱丁堡聚会,庆祝英国地理学家协会成立五十周年。协会成立于1933年,其主要宗旨是创办刊物,发表地理学家的研究成果。背景第一次世界大战后,英国大学地理系发展很快,为此,整个国家的地理研究工作也不断得到加强。 相似文献
350.
Earthquake-controlled event deposits and its tectonic significance from the Middle Permian Wandrawandian Siltstone in the Sydney Basin,Australia 总被引:3,自引:0,他引:3
DU Yuansheng G. R. Shi & GONG Yiming . Faculty of Earth Sciences China University of Geosciences Wuhan China . School of Ecology Environment Deakin University Victoria Australia 《中国科学D辑(英文版)》2005,48(9):1337-1346
Earthquake is a disaster event resulting from rapid and intensive crustal vibration caused by fault activity, volcanic eruption, or block dilapidation. Heezen and Ewing[1] and Heezen and Dyke[2] were the first to note earthquake-related mass movement and associated deposits in connection to the turbidity currents and submarine slumps triggered by the Grand Bank Earthquake in 1929. Seilacher[3] defined redeposited sedimentary beds, disturbed and modified by earth- quakes, as seismite. Since t… 相似文献