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41.
抗日战争结束后,联合国救济善后总署(以下简称“联总”)紧急采购大批美军剩余物资,用以帮助中国恢复经济;来自太平洋战区的部分剩余物资货箱品名混乱,货单极不完备,给物资移交、处置工作造成极大困难,并在联总和行总之间引起一系列误会和龃龉;经过在上海就地装配修理,绝大部分剩余物资陆续投入使用,有力地促进了我国战后交通和工矿业的恢复。  相似文献   
42.
 利用通用天文软件SKYMap Pro Version 8计算了木星和土星的月视赤纬,将其与ENSO循环及赤道太平洋关键区海温距平进行对比分析,发现两者存在明显联系,主要包括:木星视赤纬由正经过赤道变为负时,容易发生EL-Nino事件,而且事件持续时间较长,1980年代及以前发生过3次这样的情况都对应持续较长的EL-Nino事件,1980年代以后的2次EL-Nino事件群发期,其中心都发生在木星视赤纬从正向负转化期间.EL-Nino易发生在木星视赤纬的正极值和赤道附近,而负极值附近很少发生.LA-Nnia事件在1980年代及以前发生在木星视赤纬极值和赤道之间的中间视赤纬区域内,但1980年代以后,则容易发生在木星视赤纬负极值附近.一些EL-Nino事件发生年的木星视赤纬位置近乎在1条直线上,过去60年中有4条这样的直线,将EL-Nino事件分成4个组,每个组内都准确地由4个事件组成.当土星视赤纬靠近或离开赤道时(大概在±5°~10°),都会有EL-Nino发生,但在赤道区域却几乎不发生EL-Nino事件.  相似文献   
43.
大豆是世界各国主要种植的粮食作物之一,因富含脂肪和蛋白质使其成为重要的粮食贸易品种。2018年全球大豆产量已达到3.66亿t,其中美国、巴西、阿根廷3个经济体的大豆产量共占全球总产量80%左右。为推动亚太地区各经济体粮食标准互联互通,促进亚太地区粮食贸易便利化和一体化,对包括中国、美国、澳大利亚、加拿大、日本、韩国、墨西哥、菲律宾、泰国、中国台北等10个亚太经合组织经济体及巴西、阿根廷等2个大豆主产国,共12个经济体的大豆标准进行了系统分析;找出标准适用范围、产品分类、等级划分和等级参数有关质量指标等方面的相同和差异之处,对促进亚太地区大豆标准互联互通提出了建议,可为从事粮食标准化、品质检验、大豆进出口贸易的粮食工作者提供参考。  相似文献   
44.
西太平洋新军事联盟作为美、日重构亚太安全格局的危险举动,由于利益的博弈,“囚徒困境”。最根本的原因是部分国家寻求部分共同安全利益,这种囿于冷战思维下的霸权上的反映是严重背离国际制度原则的。只有坚持强调和平共处的基本原则,才可能真正重构亚所需国际制度。正面临着难解的主义心态在军事太地区安全格局  相似文献   
45.
热带西太平洋叶绿素a的时空分布   总被引:5,自引:0,他引:5  
  相似文献   
46.
Surface-and subsurface-dwelling planktonic foraminifera from the upper 43 m of Hole A at the Ocean Drilling Program (ODP) Site 807,which was recovered from the western Pacific warm pool during ODP Leg 130,were analyzed for stable oxygen and carbon isotopes.By comparing these results with data from ODP Site 851 in the eastern equatorial Pacific,this study has reconstructed the paleoceanographic changes in upper ocean waters in the equatorial Pacific since 2.5 Ma.During the period from 1.6-1.4 Ma,the oxygen isotopes of surface and subsurface waters were found to markedly change in the western and eastern equatorial Pacific,further confirming the final formation of the well-defined asymmetric east-west (E-W) pattern at that time.This feature was similar to the zonal temperature gradient (sea surface temperature is higher in the west and lower in the east) and the asymmetric upper water structure (thermocline depth is deeper in the west and shallower in the east) in the modern equatorial Pacific.The zonal gradient change of subsurface water δ18O was greater than that of surface water δ18O,indicating that the formation of the asymmetric E-W pattern in the equatorial Pacific should be much more related to the shoaled thermocline and markedly decreased subsurface water temperature in the eastern equatorial Pacific.Moreover,since ~1.6 Ma,the carbon isotopic differences between surface and subsurface waters clearly decreased in the equatorial Pacific,and their long-term eccentricity periods changed from 400 ka to ~500 ka,reflecting the reorganization of the ocean carbon reservoir.This probably resulted from the deep water reorganization in the Southern Ocean at that time and its enhanced influence on the tropical Pacific (especially subsurface water).Our study demonstrates that the tropical ocean plays an important role in global climate change.  相似文献   
47.
《Journal of Natural History》2012,46(6):1163-1175
This paper reports range extensions for seven hermatypic coral species in the Gulf of California. An analysis of the distribution and fossil record of the 12 hermatypic species of the Gulf shows that the coral communities of the Gulf are the oldest ones in the eastern Pacific. Two species have been recorded in the Gulf (or nearby) since the Pliocene and several other species since the Pleistocene. The uninterrupted fossil record falsifies the hypothesis of a total extinction of reef corals in the eastern Pacific during the Pleistocene. The fossil evidence and temperature calculations support the conjecture that the Gulf of California was a refuge zone for corals and other warm-water biotas during the same epoch. Also it is suggested that some species of the genera Porites may have an Atlantic origin, contrary to the accepted idea of an exclusive Indo-Pacific origin of the eastern Pacific coral fauna.  相似文献   
48.
Six species of deep-water chaetognaths have been caught near the bottom (at about 1300 m) during four dives of the submersible Alvin in the Santa Catalina Basin (California). Although few samples were taken, they are very interesting. New morphological data are presented on a supposed very well-known planktonic species (Sagitta macrocephala) and two new benthoplanktonic species of the genus Heterokrohnia are described. Details on the morphology and reproduction of the family Heterokrohniidae, and also on the bathymetric and zoogeographic distributions of Heterokrohnia species of the ‘longidentata’ group are given.  相似文献   
49.
《Journal of Natural History》2012,46(12):1745-1750
Five specimens morphologically indistinguishable from Randiella caribaea Erséus and Strehlow, 1986, previously known only from the Caribbean in the Atlantic Ocean, are reported from a sandy beach at Touhou, New Caledonia. The new material reveals that R. caribaea and probably also the closely related R. minuta Erséus and Strehlow, 1986 have dorsal spermathecae, an assumedly apomorphic condition vis-à-vis the lateral spermathecae of the other species of Randiellidae. The number and position of the gonads in this family are unclear, but the new material of R. caribaea appears to have at least one testis in segment X and one ovary in segment XII.  相似文献   
50.
《Journal of Natural History》2012,46(45-46):2899-2917
ABSTRACT

First sampled in the late 1990s, Campamento Tortuguero La Gloria, in Jalisco, Mexico, was resampled for olive ridley sea turtle (Lepidochyles olivacea Eschscholtz) diversity 10 years later. A comparison with all previously reported mitochondrial sequences revealed that these new samples added to the known genetic diversity for this species, and revealed unexpectedly high genetic diversity among turtles nesting on this beach. The results highlight the importance of systematic resampling in known nesting rookeries to verify the genetic diversity of study populations. Three new olive ridley haplotypes are reported, all more closely related to Baja Californian haplotypes than to Australian haplotypes. Significant genetic divergence is reported within populations, within ocean basins (Atlantic, Pacific, Indian and Indo-Pacific), and between ocean basins. Furthermore, this is the first study that integrates satellite tagging data to demonstrate diverse post-nesting migration patterns of turtles with identical haplotypes, and it demonstrates flexibility in post-nesting migratory behaviour for olive ridley sea turtles of the same genetic provenance.  相似文献   
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