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111.
Predicting the spread of nuclear radiation from the damaged Fukushima Nuclear Power Plant 总被引:1,自引:0,他引:1
FangLi Qiao GuanSuo Wang Wei Zhao JieChen Zhao DeJun Dai YaJuan Song ZhenYa Song 《科学通报(英文版)》2011,56(18):1890-1896
Japan suffered a M9.0 earthquake and massive tsunami on March 11, 2011, which seriously damaged the Fukushima Nuclear Power Plant and caused a nuclear crisis. The spread of nuclear radiation from the power plant through the atmosphere and ocean was predicted with a short-term climate forecasting model and an ocean circulation model under some idealized assumptions. If nuclear matter were leaked in the near-ground layer of 992 hPa, the climate model results show that the nuclear radiation would cover North America 10 days after the initial leakage, with the concentration at the forefront dramatically reduced to 10 millionths of the initial model concentration at the source. The radiation would span Europe in 15 days and cover much of the Northern Hemisphere in 30 days. If the initial leakage was assumed to occur in the layer 5000-m above the ground, the radiation would cover Europe in 10 days and cover much of the Northern Hemisphere in 15 days. Moreover, under the assumption that the nuclear matter leaked in the 10000-m layer, the radiation would affect much of China after 10 days. The ocean circulation model indicates that the nuclear material would be slowly transported northeast of Fukushima and reach 150°E in 50 days, and the nuclear debris in the ocean would be confined to a narrow band. Compared with the spread in the ocean, the area affected by leaked nuclear radiation in the atmosphere would be very large. Atmospheric monitors in North America and Europe will be helpful for estimating the effect in China of any leaked nuclear material. 相似文献
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Aiming at the problem of unsatisfactory effects of traditional micro-expression recognition algorithms,an efficient micro-expression recognition algorithm is proposed,which uses convolutional neural networks(CNN) to extract spatial features of micro-expressions,and long short-term memory network(LSTM) to extract time domain features.CNN and LSTM are combined as the basis of micro-expression recognition.In many CNN structures,the visual geometry group(VGG) using a small convolution kernel is finally selected as the pre-network through comparison.Due to the difficulty of deep learning training and over-fitting,the dropout method and batch normalization method are used to solve the problem in the VGG network.Two data sets CASME and CASME II are used for test comparison,in order to solve the problem of insufficient data sets,randomly determine the starting frame,and a fixedlength frame sequence is used as the standard,and repeatedly read all sample frames of the entire data set to achieve trayersal and data amplification.Finallv.a hieh recognition rate of 67.48% is achieved. 相似文献
114.
盐胁迫下酿酒酵母和鲁氏酵母渗透调节方式的对比与分析 总被引:2,自引:0,他引:2
酵母菌是耐盐的真核模式生物.为了研究酵母菌在不同盐胁迫条件下的渗透调节方式,本文以不同条件对酿酒酵母和鲁氏酵母进行盐胁迫处理,利用高碘酸钠—乙酰丙酮法及蒽酮-硫酸法分别对盐胁迫下酿酒酵母和鲁氏酵母产生的甘油和海藻糖含量进行了测定、分析与比较.结果表明,在不同盐胁迫条件下酿酒酵母和鲁氏酵母细胞内均迅速积累大量的甘油和海藻糖.盐胁迫下鲁氏酵母以甘油调节渗透平衡的能力高于酿酒酵母以甘油调节渗透平衡的能力,盐胁迫下酿酒酵母以海藻糖调节渗透平衡的能力高于鲁氏酵母的海藻糖渗透调节能力. 相似文献
115.
采用密度泛函(DFT)和PBC方法对σ-π共轭高分子电子结构和带隙进行理论研究,电荷掺杂和聚合物中π共轭链长度对带隙降低起到重要作用,发现PBD是一种窄带隙的高分子. 相似文献
116.
基于MVA的半导体生产过程质量分析方法 总被引:1,自引:0,他引:1
针对半导体晶圆生产中存在着位置间变异、晶圆间变异及批次间变异,提出了基于多变异分析(MVA)的工序质量分析方法.该方法通过建立基于方差分析晶圆生产工序质量的多变异分析模型,研究了晶圆生产过程中3种变异与总变异之间的定量关系.由定量关系推导出晶圆生产中的抽样规则,并提出了3种常用过程能力指数Cp,Cpk和Cpm的改进计算方法.通过在晶圆生产中的实际应用,证明了该方法中的抽样规则能捕获加工过程中主要随机变异,该方法计算获得的过程能力指数可较为真实地反映生产过程质量状况. 相似文献
117.
Since 2010, Chinese government has introduced a series of administrative policies to limit speculation in the housing market to stabilize price fluctuations and keep the housing market in a healthy state of development. In order to investigate whether administrative policy can play its due role, this paper constructs a comprehensive bottom-up housing market heterogeneous households multiagent model(HHMAM) to undertake research on the differentiated effect of administrative policy in different cities. The empirical studies find that: 1) Administrative policy that increases interest rates will cause housing prices to continue to decline in the long term, but they will resume a rising trend after reaching the lowest point; 2) If the government cancels a property-purchasing limitation, housing prices will continue to rise; and 3) investors tend to invest in 1~(st)-tier cities due to the high demand and greater likelihood of appreciation in these cities. 相似文献
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119.
Hu Z Xia Y Guo X Dai J Li H Hu H Jiang Y Lu F Wu Y Yang X Li H Yao B Lu C Xiong C Li Z Gui Y Liu J Zhou Z Shen H Wang X Sha J 《Nature genetics》2012,44(2):183-186
Non-obstructive azoospermia (NOA) is one of the most severe forms of male infertility. Its pathophysiology is largely unknown, and few genetic influences have been defined. To identify common variants contributing to NOA in Han Chinese men, we performed a three-stage genome-wide association study of 2,927 individuals with NOA and 5,734 controls. The combined analyses identified significant (P < 5.0 × 10(-8)) associations between NOA risk and common variants near PRMT6 (rs12097821 at 1p13.3: odds ratio (OR) = 1.25, P = 5.7 × 10(-10)), PEX10 (rs2477686 at 1p36.32: OR = 1.39, P = 5.7 × 10(-12)) and SOX5 (rs10842262 at 12p12.1: OR = 1.23, P = 2.3 × 10(-9)). These findings implicate genetic variants at 1p13.3, 1p36.32 and 12p12.1 in the etiology of NOA in Han Chinese men. 相似文献
120.
To study the effect of cooperative advertising on the supply chain of deteriorating items, this paper establishes a Stackelberg game model for a two-echelon deteriorating items supply chain composed of one manufacturer and one retailer under a given support program with an exogenous participation rate. The manufacturer as the leader determines the wholesale price and production rate, and the retailer as the follower determines the retail price and advertising strategies. The strategies of the players under the decentralized scenario and the centralized scenario are respectively characterized. Numerical simulations and sensitivity analysis are conducted to gain some managerial insights. It is shown that the pricing, advertising and production strategies are negatively correlated to deteriorating coefficient, and both the profit and the channel efficiency decrease with deteriorating coefficient; The interaction between price, advertising investment and production rate results in a higher retail price of the centralized channel compared to that of the decentralized channel; Implementing the cooperative advertising program does improve the performance of the supply chain in some cases and the participation rate roughly at 0.5 is most preferable, but it is also possible to distort incentive and damage the channel performance when the participation rate reaches a relatively high level. 相似文献