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101.
《Journal of Natural History》2012,46(5):1129-1153
Pseudophyllodistomum gen. nov. is proposed for a section of Phyllodistomum Braun, 1899. The new genus is distinguished by the simple form of the uterus, the eggs which reach over 60 μm long in length, the saccular excretory bladder, the 2[3 + 3 + 3) + (3 + 3 + 3)] = 36 flame-cell formula, the metacercaria which may have fully developed genitalia and is parasitic in decapod crustaceans, the use of corbiculid bivalves as first intermediate hosts, and the cercaria which has a long tail not enclosing the cercarial body. Two species, P. johnstoni sp. nov. and P. murrayense sp. nov., are described from Australian freshwater fish and five new combinations of previously described Phyllodistomum species from Asian freshwater fish are proposed — P. macrobrachicola (Yamaguti, 1934) comb. nov., P. lesteri (Wu, 1938) comb. nov., P. srivastavai (Rai, 1964) comb. nov., P. lucknowense (Pandey, 1970) comb. nov. and P. mingense (Tang, 1985) comb. nov. The first intermediate host of P. johnstoni is a Corbiculina species. The long-tailed cercariae infect the gonads of palaemonid prawns, Macrobrachium spp., in which they grow to unencysted metacercariae which may have fully developed genitalia. The metacercaria of P. murrayense also infects a Macrobrachium species. The evolution of the Gorgoderinae is discussed and it is suggested that, prior to the erection of Pseudophyllodistomum, Phyllodistomum may have encompassed as many as five different phylogenetic lines, each with similar adult morphology but distinguishable by life-cycle characters. It is postulated that more study will lead to further division of Phyllodistomum. 相似文献
102.
《Journal of Natural History》2012,46(7):1039-1048
Diathera gen. n., a new larentiine genus from central and southwestern China, is described. Three new species are named and described: fluctuata sp. n., metacolorata sp. n. and brunneata sp. n. All species and their genitalia are described and illustrated. A key is provided and the monophyly of the genus and its relationships to the allied taxa are briefly discussed. 相似文献
103.
This essay considers the development of the nuclear science programme in Malaysia from a transnational perspective by examining the interactions between state agents and other external nuclear-knowledge/technology related actors and agents. Going beyond the model of knowledge diffusion that brings together concerns articulated in Harris’s (2011) geographies of long distance knowledge and Reinhardt's (2011) role of the expert in knowledge transfer, the proposed three-phase model of knowledge transfer theorises the pathways undertaken by a late-blooming participant of modern science and technology as the latter moves from epistemic dependency to increasing independence despite the hurdles encountered, and the underdevelopment of many areas of its technoscientific economy. The model considers tensions stemming from the pressures of expediency for meeting national developmental goals on the one side, and the call to support the objectives of basic science on the other. The three phases of the model are epistemic transition, epistemic transplantation and localisation, and epistemic generation (ETTLG). As additional support for the proposed model, three arguments are proffered as deeper explanations of the epistemic goal by using Malaysia as a case study: knowledge transfer for political legitimization, knowledge transfer for countering agnotology, and knowledge transfer for social engineering and science diplomacy. 相似文献
104.
谭惠敏 《大连民族学院学报》2016,18(4):401-403
立足大连的区位优势,通过历史的、比较的方法分析了大连与东亚发展的契合点,认为大连面向东亚地区进行汉语国际推广应与“一带一路”战略相融合,大连高校应结合自身优势,充分发展并创新汉语国际推广模式。提出了扩宽国际化办学方向、充分利用大连的国际“品牌”等发展思路。 相似文献
105.
川东南地区嘉陵江组T_1j~(2-1)-T_1j~1碳酸盐岩储层具有低孔隙度、低渗透率、单层厚度薄、非均质性强的特征,勘探难度较大.综合考虑T_1j~(2-2),T_1j~(2-1)和T_1j_1地层的地质特征,通过地质、测井进行合成记录层位标定,建立正演模型, 探讨了旺隆及周边地区储层的测井响应特征和地震响应特征,提取了地震属性对储层进行横向预测研究.结果显示,中-强振幅、同相轴下拉、同相轴分叉、频率降低现象代表储层发育.地震属性分析结果表明太和、旺隆地区储层较发育,这与钻井显示较吻合,说明该方法可以较好地预测出该套储层的分布范围,为进一步勘探提供了依据. 相似文献
106.
The Jurassic is a period of intensive accretion along the eastern and southeastern margins of the Asian continent. The emphasis of the present study is the review of the Jurassic prism structure of the Russian Far Eastern Pacific Asian margin and comparison with its equivalent in the Japanese archipelago. The Jurassic accretion processes and geodynamic evolution of the Paleo-Asian continent eastern margins are outlined in the paper. During this period, the different ages and different facies fragments of the Paleo-Pacific, such as abyssal plain, intraoceanic volcanic seamountains and oceanic plateaux, were accreted onto the eastern margin of the Paleo-Asian continent as a result of step-wise subduction of oceanic lithosphere. Together with ocean-margin terrigenous deposits (trench-fill turbidites), these paleooceanic fragments formed a thick tectono-sedimentary complex of the Jurassic accretionary prism, causing the size of the continent to be expanded by an increase along its eastern margin. 相似文献
107.
中亚塔吉克斯坦南部的黄土序列与中国黄土高原相似, 呈现黄土?古土壤交替的特征, 前人研究发现塔吉克斯坦黄土序列中以PC3为界的下部黄土与古土壤单元磁化率明显低于上部地层, 目前对这一现象尚无合理的古气候解释。本文对中亚塔吉克斯坦南部Darai Kalon黄土剖面的典型样品进行系统的矿物磁学研究以及漫反射光谱测量, 结果表明, 从黄土序列的下部到上部, 亚铁磁性矿物的总量以及超顺磁与单畴磁性颗粒的含量均呈增长的趋势, 与此同时, 硬磁性组份(如赤铁矿或针铁矿)的含量逐渐减少, 这可能指示成壤作用强度随时间增强。赤铁矿的适宜生长条件为高温干燥环境, 因此黄土序列下部的较高赤铁矿含量可能支持气候逐渐变湿的推论, 即下部地层沉积时期气候偏干, 成壤作用较弱, 古土壤中含较少的亚铁磁性矿物, 超顺磁与单畴磁性矿物颗粒较少, 故下部地层的磁化率较低。然而, 光谱测量数据显示, 下部地层针铁矿含量高于上部地层, 由于针铁矿的适宜生长条件为湿润环境, 其含量向上逐渐降低的趋势当指示气候逐渐变干。因此, PC3以下地层的较低磁化率也可能是过于湿润的环境溶解超顺磁和单畴磁性矿物颗粒造成的。尽管高场(达2 T)等温剩磁结果显示上部地层中以赤铁矿为主的硬磁性矿物含量较少, 但上部地层红度(a*)与赤铁矿含量之间较弱的相关性指示基体效应可能对光谱测量结果产生强烈的影响, 导致对赤铁矿光谱数据的解释存在很大的不确定性。针铁矿含量与磁化率的良好负相关性的确指示从下至上气候变干的趋势, 这一趋势与该地区前人的孢粉学和地球化学研究结果一致。以上研究结果表明, 对于中亚塔吉克斯坦南部黄土?古土壤序列的磁化率乃至矿物磁学数据的古气候解释非常复杂, 在中亚黄土研究中应用基于中国黄土磁学研究的模式需要谨慎, 有必要结合多指标进行综合分析。 相似文献
108.
冷战以后东南亚地区安全环境发生了很大变化,政治领域,经济领域安全问题错综交织,加之近年来非传统安全的兴起,都加剧了东南亚地区的安全困境。在新时代的国际安全环境下,各种以地区性为主的国际合作安全机制应运而生。本文分析东南亚地区安全合作的驱动力,东南亚地区安全合作的可能性与具体建议以及东南亚地区安全合作对亚太地区安全的影响。 相似文献
109.
湘东南拗陷是中国南方古生代~新生代叠合盆地之一,古生代~中生代地层普遍裸露,该拗陷油气勘探程度较低。在野外剖面观测、室内薄片鉴定等工作的基础上,分析了湘东南拗陷上古生界碳酸盐岩储层成岩作用类型,包括:泥晶化作用、胶结作用、压溶作用、白云石化作用、重结晶作用、裂缝化作用、溶蚀作用等,以及经历的海底-大陆(淡水和混合水)-浅埋藏-深埋藏-表生等成岩环境。对储层孔隙发育起建设性的成岩作用主要有裂缝化作用、压溶作用、溶蚀作用和白云石化作用。裂缝化作用及压溶作用在一定程度上可改善储层的储集性能。白云石化作用形成的白云石晶间孔为重要的孔隙类型,并成为工区最为有利的勘探目的层。 相似文献
110.
略论清朝经营黔东南苗疆政策的演变 总被引:1,自引:0,他引:1
清朝对黔东南苗疆的经营大致可分为绥抚期、开辟期、苗汉分治期以及开放期等,前三个时期由于国内政治背景迥异,清朝对其实施了各不相同的民族政策,对于巩固西南民族地区的统治曾发挥了积极作用;苗疆最后进入开放期,是在成同苗民起义沉重打击下,清朝在苗疆的行政机构趋于瘫痪所致。 相似文献