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41.
走滑拉分断块对沉积的控制作用——准噶尔盆地东部侏罗系中下统沉积主控因素新认识 总被引:2,自引:0,他引:2
通过在南缘露头剖面相构型识别,北部地震剖面解释的沉积体侧向迁移特征,建立了走滑拉分构筑的可容空间变化型式。此沉积对构造的响应模式,不仅可以很好的解释拼合砂体的分布,古流向偏转等问题,而且对于预测盆内沉积体走向也是一个很有用的工具。 相似文献
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洱海叶绿素a浓度的季节动态和空间分布 总被引:3,自引:0,他引:3
2010年5月至2011年4月,对洱海叶绿素a的季节动态、空间分布及其与环境因子的关系进行研究.结果表明,水体中叶绿素a浓度存在明显的季节变化,其变化范围为4.11~24.30μg/L,年平均值为10.4±6.5μg/L,最小值出现在2011年3月,最大值出现在2010年9月.叶绿素a浓度在夏、秋季较高,冬、春季较低.在空间变化上,叶绿素a浓度在南部湖区最大,其次是北部湖区,中部湖区最低.Pearson相关系数和主成分分析表明,洱海叶绿素a浓度在不同湖区中与水温和透明度均呈极显著相关.总氮在北部和南部湖区与叶绿素a浓度均存在一定的相关性,而总磷与叶绿素a浓度在南部湖区存在一定的相关性.根据修正的卡尔森营养状态指数,洱海综合TSI值为50.6,水质处于中营养状态. 相似文献
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以全鱼粉作为唯一蛋白源(D1),用豆粕替代10%、20%鱼粉(D2、D3),玉米蛋白粉替代10%鱼粉(D4),啤酒酵母替代10%鱼粉(D5),配制5组等氮等能饲料,每种饲料设置3个实验组,进行56 d的养殖实验。通过血液和组织涂(印)片、细胞染色和显微观察,研究人工培育的褐点石斑鱼幼鱼外周血液白细胞的分类组成,头肾、脾脏、体肾和肝脏等4种组织中各类血细胞的发生情况,以及不同蛋白源饲料对褐点石斑鱼血细胞发生的影响。结果表明:褐点石斑鱼外周血液中的白细胞由淋巴细胞(53.30%±4.66%)、血栓细胞(35.69%±3.85%)、嗜中性粒细胞(10.34%±3.14%)、单核细胞(0.28%±0.36%)、浆细胞(0.24%±0.34%)和嗜酸性粒细胞(0.15%±0.27%)组成;组织印迹片中,未成熟的红细胞、淋巴细胞和粒细胞主要在头肾印迹片中出现,未成熟的单核细胞主要在头肾和脾脏印迹片中出现,血栓细胞在肝脏印迹片中数量最多,推断褐点石斑鱼幼鱼主要的造血组织是头肾,其次是脾脏;在4种组织中均观察到浆细胞,在体肾印迹片中观察到嗜碱性粒细胞,在肝脏印迹片中观察到巨噬细胞,在头肾印迹片中还观察到巨大原红细胞。显微观察和数据统计分析的结果都表明,投喂5种蛋白源不同的配合饲料,未对褐点石斑鱼4种组织中血细胞的发生情况造成显著影响。 相似文献
45.
Summary The sensitivity of the simulation of the monsoon depressions to the cumulus parameterization schemes used in a numerical model
is studied using the Pennsylvania State University – National Center for Atmospheric Research (PSU-NCAR) model MM5 version
3.6.2. Three different cases of monsoon depressions were studied with a two way interacting domains of 45 km and 15 km resolutions.
Two different cumulus parameterization schemes namely Grell (GR) and Kain-Fritsch (KF) were used for the sensitivity study.
The model was integrated for 48 hours with the initial and boundary conditions of European Center for Medium Range Weather
Forecasting Reanalysis (ERA-40) data. The results show that both the schemes are able to simulate the large scale features
of the monsoon depressions realistically. However, both the schemes failed to simulate the exact location of the depression
after 24- and 48-hour simulation. The rainfall simulations of both the schemes were very different. The model with the GR
scheme tends to over predict the rainfall. The KF scheme could simulate the distribution of the rainfall comparable to the
observations. The KF scheme could simulate the maximum observed rainfall but due to locational errors of the simulated depression,
the location of the maximum rainfall was not exact. It is also seen that the resolution of the model has a positive impact
on the rainfall simulation. The GR and KF schemes were able to realistically simulate the apparent heat sources, but the apparent
moisture profile simulated with KF scheme was more comparable to the verifying analysis. The root mean square errors of mean
sea-level pressure, temperature, zonal wind and meridional wind were smaller for KF simulation compared to the GR simulation.
Permanent affiliation: Center for Development of Advanced Computing, Pune University Campus, Ganeshkhind, Pune-411 007, India. 相似文献
46.
紧密结合国家非常规能源勘探开发的重大战略,聚焦重庆涪陵页岩气勘查开发区环境地质调查工作,总结了研究区岩溶发育特征与分布规律,评价了涪陵页岩气开发区区域水资源量和地下水质量。在此基础上,收集分析国内外资料,梳理了页岩气勘查开发所引发的6类环境(地质)问题及勘查、钻井、压裂、开采、闭井等5个阶段需关注的地质环境问题或风险等,其中涪陵页岩气勘查开发区主要诱发水土污染、地质灾害和大气污染等环境(地质)问题; 基本识别了2种地下水污染模式、3种污染类型及可能的地下水污染风险途径; 初步确定了涪陵页岩气勘查开发区污染指示性特征因子,并形成了页岩气勘查开发区地质环境影响评价指标体系,可指导页岩气勘查开发的环境地质调查。该研究为页岩气国家新型清洁能源的绿色开发和开发区生态文明建设提供支撑。 相似文献
47.
48.
对取自桑沟湾北西南三根柱样近200 a碳来源及埋藏通量的解析,分析了湾内不同站位各形态碳的差异性,进而对全湾碳埋藏进行了估算。湾内环流、贝藻养殖等造成湾内不同区域碳埋藏的差异;桑沟湾总碳(TC)平均量1.79%,有机碳(TOC)平均量0.54%,无机碳(TIC)平均量1.25%,TOC含量相对较小,为海陆混合来源,以陆源有机碳(Ct)为主,大规模人工养殖后,海源有机碳(Ca)有明显增加的趋势。桑沟湾碳埋藏通量平均为228.9 g/(m2·a),以无机碳为主要埋藏形式(约占70%),高的沉积速率及生物残骸沉降使桑沟湾养殖区碳的来源及埋藏区别于其他陆架海域。 相似文献
49.
50.
Hsin-Ting?Su Sai?Hung?CheungEmail author Edmond?Yat-Man?Lo 《Stochastic Environmental Research and Risk Assessment (SERRA)》2018,32(4):1147-1162
In flood risk management, the divergent concept of resilience of a flood defense system cannot be fully defined quantitatively by one indicator and multiple indicators need to be considered simultaneously. In this paper, a multi-objective optimization (MOO) design framework is developed to determine the optimal protection level of a levee system based on different resilience indicators that depend on the probabilistic features of the flood damage cost arising under the uncertain nature of rainfalls. An evolutionary-based MOO algorithm is used to find a set of non-dominated solutions, known as Pareto optimal solutions for the optimal protection level. The objective functions, specifically resilience indicators of severity, variability and graduality, that account for the uncertainty of rainfall can be evaluated by stochastic sampling of rainfall amount together with the model simulations of incurred flood damage estimation for the levee system. However, these model simulations which usually require detailed flood inundation simulation are computationally demanding. This hinders the wide application of MOO in flood risk management and is circumvented here via a surrogate flood damage modeling technique that is integrated into the MOO algorithm. The proposed optimal design framework is applied to a levee system in a central basin of flood-prone Jakarta, Indonesia. The results suggest that the proposed framework enables the application of MOO with resilience objectives for flood defense system design under uncertainty and solves the decision making problems efficiently by drastically reducing the required computational time. 相似文献