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121.
The key indicators of transboundary water apportionment based on international laws and cases 总被引:1,自引:0,他引:1
Transboundary water, more competitive utilization and uncertain availability under the globalization trend, the issue of its apportionment which directly impacts national benefits of each riparian state is becoming one of the important topics in the world. Water is scarce in China, the most important upstream state in Asia, and this task has to be thought over in the coming future. Based on "International Freshwater Treaties Database" (1820-2007) by Oregon State University, and publications and reports on transboundary water utilization and management since 1999, 28 indicators of water apportionment adopted in 49 international treaties and cases in 1864-2002 are divided into 6 types, the spatial and temporal characteristics of the adopted indicators are analyzed in order to find the key indicator(s) of transboundary water apportionment. The major results include: the major adopted indicators, have significant differences among 5 regions/continents, the indicators at rank first and second place in the developed region (North America and Europe) according to the adopted times are "keeping minimum water flow" and "mean annual runoff", but in the developing region (Asia, Africa and South America), the ranking order of the above two indicators is reversed; the major adopted indicators in the watersheds with insufficient water are "mean annual runoff" and "keeping minimum water flow", the ones in the watersheds with sufficient water are "keeping minimum water flow" and "maximum water intake"; the international treaties signed from the first phase to the fourth phase, the developing process shows a progress of "fewer-increasing a lot-decreasing rapidly-equation basically", the regional distribution of the treaties shifts mainly from the developed region to the developing one, especially to Asia and Africa; the major adopted indicators shifts from "keeping minimum water flow" and "mean annual runoff" in 1864-1945, to "keeping minimum water flow" and "maximum water intake" in 1946-1971, then to "hydraulic facility operation" and "mean annual runoff" in 1972-1991, and finally to "keeping minimum water flow" and "mean annual runoff" in 1992-2002, the process shows similar a loop. Finally, the key indicator on transboundary water apportionment can be determined as "keeping minimum water flow". 相似文献
122.
Darija Vukić Lušić Dražen Lušić Denis Pešut Vladimir Mićović Marin Glad Lovorka Bilajac Vesna Peršić 《Marine pollution bulletin》2013
The quality of bathing water is of considerable public importance due to the possibility of fecal contamination. In 2009, Croatia implemented the new European Bathing Water Directive (BWD, 2006/7/EC) establishing stricter microbiological standards for new parameters with new reference methods. This study aims to evaluate the equivalence of different methods according to the old and revised BWD and to provide the possibility of data comparison. Furthermore, the directive requires the establishment of the bathing water profile (BWP) for pollution risk assessment. The estimation of consistency of pollution risk assessment with obtained microbiological results was also performed. 相似文献
123.
Ying Zhang Zhenbo Lv Bo Guan Yuanjin Liu Fan Li Shaowen Li Yuanqing Ma Junbao Yu Yunzhao Li 《洁净——土壤、空气、水》2013,41(10):1027-1034
Laizhou Bay, located in the northwest of Shandong Peninsula, has complex transitional environments between terrestrial and marine ecosystems. In the present study, a total of 122, 131, and 139 species were collected in spring, summer, and autumn 2011, respectively. Species constitutions of macrobenthos were grouped into four phyla, of which annelida were the most abundant phylum, the average biomass proportion of echinodermata was the lowest, and the proportion of important species for mollusca was the highest. The structure of the macrobenthic community showed significant differences between sites, and greater divergence was observed between the third site (S03) and other stations. The ABC plots showed that the biomass curve lay below the abundance curve, and the W‐statistic value was negative. The result of the BOPA index showed that two stations had moderate ecological status in spring and that there were two heavily polluted sites and one moderately polluted site in summer. The BIO‐ENV analyses indicated that the grain‐size fractions together with trace metals (Hg, Pb, Zn, Cu, and Cr) could be considered as the major environmental variables influencing the macrobenthic patterns. The results together demonstrated that the macrobenthic communities in Laizhou Bay were negatively affected, perhaps by the tremendous impact of heavy metals in the sediments. 相似文献
124.
德化淳湖金矿产于侏罗系上统南园组第四段酸性火山碎屑岩中,主要受祭坑—淳湖北西向断裂的次级断裂控制。目前已发现4条金矿体。矿体呈长透镜状产出,矿石主要为黄铁矿化石英脉型、绢云母化黄铁(褐铁)矿化硅化蚀变岩型。初步研究表明该金矿为与晚侏罗世火山作用有关的构造蚀变岩型金矿。 相似文献
125.
河南桐柏歇马岭金矿床地质特征及找矿标志 总被引:1,自引:0,他引:1
通过对歇马岭金矿地质特征和矿化富集规律的初步分析,提出了找矿标志和找矿模型,对矿区及外围进一步找矿提供了思路. 相似文献
126.
127.
西藏多不杂矿集区斑岩铜矿地球化学指标研究 总被引:2,自引:0,他引:2
多不杂矿集区位于西藏改则县北部,是近些年发现的超大型斑岩型铜矿床,在以多不杂为中心,东西长约30km,南北宽约10km的范围内,包括多不杂、波龙、色那、拿顿、拿若、尕尔勤和铁格龙7个矿区。本文在前人工作的基础上,通过对矿集区钻孔岩芯样品地球化学数据进行旋转正交因子处理和成矿元素Cu与稀土元素La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu、Y、微量元素U、Th的相关性分析,发现轻重稀土元素均在Cu矿(化)体部位相对富集。另外微量元素U、Th(尤其是Th),与金属元素Cu含量随深度的变化也存在一定的对应关系,在Cu矿化部位相对富集。研究表明稀土元素La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu、Y与微量元素U、Th可能是一种潜在有效的矿产勘查地球化学指标。 相似文献
128.
西藏甲玛铜多金属矿床角岩中黑云母矿物化学特征及地质意义 总被引:3,自引:0,他引:3
甲玛铜多金属矿床角岩中黑云母按其产状可区分为原生黑云母和热液黑云母,本文采用扫描电镜对两类产出状态的黑云母进行了观察,采用电子探针(EPMA)对这两类黑云母进行了微区原位成分分析,并根据电子探针数据计算了黑云母的矿物化学式。角岩中的原生黑云母和热液黑云母均属于镁质黑云母,二者都经受了热液流体的改造作用。从原生黑云母到热液黑云母Fe3+和Fe2+分异程度加大,Fe3+含量升高,Fe2+含量降低,指示了岩浆-热液流体逐渐向氧化态过渡。相比于原生黑云母,Cu元素更易于在热液黑云母中富集。角岩型矿石中的Cu含量与热液黑云母的Fe2+/(Fe2++Mg2+)比值呈正相关,与其Fe3+/Fe2+比值呈负相关,对于热液黑云母所在的角岩型岩矿石样品,其矿化强度或可以黑云母的Fe2+/(Fe2++Mg2+)比值来衡量;而Mo元素在两类黑云母中均广泛分布,不具有选择性赋存的特征。 相似文献
129.
130.
以济南市区及郊区农田土壤为对象,研究土壤中重金属污染的特征,结果表明,土壤重金属污染不仅引起了生态环境的恶化,而且影响土壤生物多样性,降低了土壤活性。济南市土壤动物各类群的数量与土壤重金属元素含量的相关性统计结果显示:土壤原生动物数量与Co、Ni含量呈明显负相关;土壤线虫数量与Cu、Mo含量呈显著负相关;旱生土壤动物数量与Cu含量呈显著负相关;说明重金属元素对土壤动物多样性具有不利影响,土壤线虫是耐污种类,旱生动物多为不耐污种类,土壤线虫与旱生动物密度之比可以作为土壤重金属污染程度的生物学指标。通过对土壤地球化学元素含量与土壤生物学参数的相关性分析,找到了重金属的敏感生物指标:Pb污染的生物学指标为土壤线虫;As污染的生物学指标是真菌PLFA含量等,用土壤生物作为敏感、快速的重金属污染生物毒性的指示物,具有广阔的应用前景。 相似文献