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71.
The economic development, living standard of residents and carbon emissions in Northwest China are lower than the national average. However,with the favorable policies the economic development is being improved and the household living standard is gradually raised up which will lead to an increase of the residents living carbon emissions, and the emission pattern will also be affected. This is detrimental to the fragile ecological environment of the Northwest China. At present, most of the researches on residents' carbon emissions are focused on the eastern and southern regions of China where there are frequent and significant human activities and high carbon emissions, and less attention has been paid to the northwest region, but the increase of carbon emissions and the increase of environmental costs have a more far-reaching impact on the less developed areas. In addition, when researchers pay attention to the prediction of residents' carbon emissions, they usually focus on the quantitative prediction and ignore the spatial pattern prediction, which is not conducive to the coordinated development between regions. Based on the data of energy consumption and consumption expenditure in the five provinces of Northwest China, including Shaanxi, Gansu, Qinghai, Ningxia and Xinjiang from 1997 to 2016, this paper firstly used the direct coefficient method to measure the residents' direct carbon emissions, and the input-output method to calculate the indirect carbon emissions of the residents and analyzes the present situation of residents' carbon emissions in the northwest region. Secondly, based on standard deviation ellipse and Autoregressive Integrated Moving Average Model, the carbon emissions of residents in Northwest China were predicted in terms of quantity and spatial pattern from 2017 to 2021. Major results are listed as follows: From 1997 to 2016, household carbon emissions in Northwest China showed a rising trend with an initial slow pace followed by a quick pace. The direct carbon emissions were stabilized in the range from 0. 3 × 108 t to 0. 4 × 108 t,and the indirect carbon emissions reached 2. 38 × 108 t. The spatial distribution of household carbon emissions in Northwest China was generally steady with a direction pattern from northwest to southeast. And the moving trend of standard deviation ellipse was from northwest to southeast to northwest, and the center of standard deviation ellipse moved around the point of (99. 07 °E,38. 19°N). From 2017 to 2021, the direct household carbon emissions in Northwest China reach to 0.543 × 108 t and the indirect carbon emissions are 3. 631 × 108 t by 2021. With the development of the western region in China and the promotion of poverty alleviation,Xinjiang Province had a lower emission than Shaanxi,but it had the higher growth rate than Shaanxi. These factors are all driving the main areas of carbon emission northwestward. The purpose of this paper is to recommend how to coordinate between the population and consumption and the environment, leading citizens to establish the value of low-carbon consumption. © 2019 Science Press (China). All rights reserved. 相似文献
72.
This article illustrates the main difficulties encountered in the preparation of GHG emission projections and climate change mitigation policies and measures (P&M) for Kazakhstan. Difficulties in representing the system with an economic model have been overcome by representing the energy system with a technical-economic growth model (MARKAL-TIMES) based on the stock of existing plants, transformation processes, and end-use devices. GHG emission scenarios depend mainly on the pace of transition in Kazakhstan from a planned economy to a market economy. Three scenarios are portrayed: an incomplete transition, a fast and successful one, and even more advanced participation in global climate change mitigation, including participation in some emission trading schemes. If the transition to a market economy is completed by 2020, P&M already adopted may reduce emissions of CO2 from combustion by about 85 MtCO2 by 2030 – 17% of the emissions in the baseline (WOM) scenario. One-third of these reductions are likely to be obtained from the demand sectors, and two-thirds from the supply sectors. If every tonne of CO2 not emitted is valued up to US$10 in 2020 and $20 in 2030, additional P&M may further reduce emissions by 110 MtCO2 by 2030. 相似文献
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74.
数字遥测地震台网采用无线信道在国内地震界借鉴的经验还非常有限。究竟数字无线遥测,能否在(10^-6)误码率指标下,象模拟无线遥测地震台网一样采用单向传输,尚有不同看法。从三峡无线数字遥测地叶网的成功勘选得一邓许多有益的结果,我们关于鸨线信道和信道设备的探索回答了这个问题。结论是:数字地震台网仍然可以采用无线遥测方式组网,采用传输的信道设备既经济原则,技术上也是可行的。 相似文献
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76.
本文依据白光耀斑连续发射谱的一般观测事实,通过对一系列模型大气的非局部热动平衡计算,从半经验角度探讨了白光连续发射与模型大气的关系。结果表明:光球深层的温度增加或者过渡区存在平台结构均可解释观测到的白光辐射增强。对如何从理论上来解释这些大气结构本文也提出了一些看法。 相似文献
77.
78.
S. Zamfir J. W. Sulentic P. Marziani 《Monthly notices of the Royal Astronomical Society》2008,387(2):856-870
We search for a dichotomy/bimodality between radio-loud (RL) and radio-quiet (RQ) type 1 active galactic nuclei (AGN). We examine several samples of Slogan Digital Sky Survey (SDSS) quasi-stellar objects (QSOs) with high signal-to-noise ratio optical spectra and matching Faint Images of the Radio Sky at Twenty-cm/NRAO VLA Sky Survey (FIRST/NVSS) radio observations. We use the radio data to identify the weakest RL sources with a Fanaroff–Riley type II (FR II) structure to define a RL/RQ boundary which corresponds to log L 1.4 GHz = 31.6 erg s−1 Hz−1 . We measure the properties of broad-line Hβ and Fe ii emission to define the optical plane of a 4DE1 spectroscopic diagnostic space. The RL quasars occupy a much more restricted domain in this optical plane compared to the RQ sources, which a 2D Kolmogorov–Smirnov test finds to be highly significant. This tells us that the range of broad-line region kinematics and structure for RL sources is more restricted than for the RQ QSOs, which supports the notion of dichotomy. FR II and CD RL sources also show significant 4DE1 domain differences that likely reflect differences in line-of-sight orientation (inclined versus face-on, respectively) for these two classes. The possibility of a distinct radio-intermediate (RI) population between RQ and RL source is disfavoured because a 4DE1 diagnostic space comparison shows no difference between RI and RQ sources. We show that searches for dichotomy in radio versus bolometric luminosity diagrams will yield ambiguous results mainly because in a reasonably complete sample, the radio brightest RQ sources will be numerous enough to blur the gap between RQ and RL sources. Within resolution constraints of NVSS and FIRST, we find no FR I sources among the broad-line quasar population. 相似文献
79.
硒元素是人体必需的微量元素之一,食用富硒农产品是人体获取和补充硒元素的主要途径,调查区域硒地球化学特征是有效地利用富硒土地资源以及开发富硒农副产品的重要依据。本文选择四川省昭觉县域内较为重要的农耕乡镇采集表层土壤样品,采用原子荧光光谱法、X射线荧光光谱法、电感耦合等离子体质谱/发射光谱法等方法测定1328件土壤、19件玉米及20件土豆中硒等地球化学指标含量,利用相关分析与统计学等方法,结合距离加权反比插值法,探讨研究区硒含量、分布和影响因素等地球化学特征,评价土壤与作物的富硒情况及安全性。结果表明:①研究区表层土壤硒含量范围为0.04~1.50mg/kg,平均值为0.33mg/kg,划定富硒土壤面积为7.23km2,占全区土壤面积的30.31%,玄武岩发育的土壤硒含量最高,平均值为0.4mg/kg,表明区内地质背景与土壤硒含量密切相关,区内富硒土壤主要受含玄武岩夹苦橄岩、凝灰质砂泥岩的峨眉山玄武岩组地层控制;②不同的用地类型和土壤类型对硒元素的富集能力不同,人为农业活动导致土壤对硒的吸附能力下降,黄棕壤土层中黏粒或铁氧化物等易与硒结合富集;酸性土壤中硒含量与pH值成反比;土壤有机质与硒含量呈显著的正相关;土壤质地对硒含量具有一定的控制作用;③富硒土壤产出的玉米和土豆富硒率极低。研究结果认为昭觉县在开发利用富硒土壤时,旱地与水田等农耕区应及时补充有机肥并调节土壤酸碱度,并积极利用富硒资源开发其他农业产品。 相似文献
80.
建立了王水溶矿-电感耦合等离子体发射光谱法测定砷矿石和锑矿石中主、次量元素砷、锑、硫及含量范围在100μg/g以上的铜、铅、锌等元素的方法。研究了放置时间、溶液酸度、氧化剂与络合剂对砷、锑、硫及其他元素测定的影响。不同王水浓度酸度对可同时测定的其他元素的影响不明显;当溶液酸度较小时,不能放置,应及时测定;如需放置,应在溶液定容前加入酒石酸防止水解。样品中砷、锑、硫的含量在0.74%~39.7%时,相对误差(RE)在-0.17%~7.74%,5次独立测定的相对标准偏差(RSD)均小于2%;含量在100~500μg/g以下的Sb,RE在-2.5%~4.79%,5次独立测定的RSD均小于2%。由于稀释倍数较大(DF=1000),不能准确测定含量在100μg/g以下的铜、铅、锌;含量在100μg/g以上的铜、铅、锌的RE在-10.3%~10.3%,5次独立测定的RSD基本小于5%。经标准物质验证获得满意结果。方法也可应用于砷、锑含量较高的硫化矿的测定。 相似文献