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991.
A theoretical model is considered that describes, in a continuum approximation, formation of a segment of angle points on the middle planes of thin layers forming a multi-layer structure. These points are associated with the jumps of the slope of the middle planes on the segment. A 2-D case is dealt with. The structure is assumed to be a half-plane with its boundary parallel to the layers and acted upon by a symmetric distribution of the displacements normal to the boundary. The layers forming the structure are assumed capable of mutually gliding with respect to each other and of revealing their flexure rigidity under the above loading. The continuum approximation to describe the above multi-layer structure has been applied. Physically the above mathematical angle points may (depending on the layer material properties) emerge either as a result of transverse fracture of the layers or as a result of intensive local plastic deformation (formation of the plastic `hinges'). As a result, the bending moment drops drastically, so that it is assumed dropping down to zero. This condition is employed to determine the distribution of the above slope jumps. The segment length is determined by equating the bending moment at the remote (from the boundary) end of the segment to a critical (specified) value of the bending moment. Thus, the problem of determining the slope jumps on the segment is reduced to a Fredholm integral equation of the first kind with the kernel having an integrable singularity. This equation has been solved numerically. The results of the calculations are presented. 相似文献
992.
用新的电路形式提高HBT光调制器驱动电路的传输速率及性能 总被引:1,自引:1,他引:0
在传统光调制器驱动电路中,所用HBT截止频率的大小要达到驱动电路传输速率的4倍以上.文中在输出级采用共射共基HBT形式后,其器件的截止频率只需大于电路传输速率的2倍即可,从电路设计的角度降低了对所用器件的要求.文中分析了新的电路结构提高传输速率的原因并给出了模拟结果.同时新的电路结构也具有良好的热稳定性. 相似文献
993.
东营凹陷滚动勘探开发技术研究与应用 总被引:4,自引:0,他引:4
东营凹陷已进入勘探开发成熟期 ,滚动勘探开发是增储稳产的主要手段 ,精细油藏描述是其关键。总结滚动勘探开发的 4种方式 (老区扩边、发现新块、发现新层系和新区滚动勘探开发 ) ,对断块复杂程度提出按每平方千米内所有断层的累加长度划分的新方法 ,从构造描述、储集层描述和油藏描述方面介绍了滚动勘探开发的技术方法。以永 8断块为例 ,在层位标定、反射特征分析、构造描述流程、地震地质分析等方面进行深入分析 ,归纳精细油藏描述的具体方法 ,强调了三维地震数据体的相干分析、属性分析等技术的重要作用。应用这一滚动勘探开发技术 ,使东营凹陷每年新增滚动储量近2 0 0 0× 10 4 t。图 3参 10 相似文献
994.
辽河东部凹陷北部不整合类型及油气成藏规律 总被引:19,自引:0,他引:19
不整合对油气藏形成有重要作用。辽河幼陷东部凹陷北部地区不整合较发育,根据实际资料研究沙三段顶面不整合类型(削截、平行和超覆)和不整合面上下6类岩性接触关系的平面分布。不整合类型和不整合面上下岩性接触关系不同,对油气藏形成的作用不同:下泥上砂的削截和平行不整合可在不整合面之上成藏;下砂上泥的削截不整合易在不整合面之下形成不整合遮挡油气藏;地层超覆不整合可形成地层超覆油气藏;不整合面上下均为砂岩,可作为沙三段烃源岩生成油气的运移通道;不整合面上下均为泥岩,可起封堵和区域盖层的作用。根据上泥下砂的不整合面分布区有利于形成不整合遮挡油气藏的认识,预测青龙台构造高部位和茨榆坨潜山的低带是有利目标区。图5参12 相似文献
995.
The effects of halide-and sulfur-containing additives on iron corrosion in 1 M H2SO4 in the presence of nucleophilic o-hydroxyazomethine derivatives are studied. Dependences of the inhibition factor (as well as its sensitivity to a change in
the polarity of the substituents) and the effective activation energy on the nature and concentration of both the groups of
additives are interpreted in terms of the Linear Gibbs Energy Relation (LGER) and the principle of Hard and Soft Acids and
Bases (HSAB).
Original Russian Text ? V.P. Grigor’ev, V.V. Boginskaya, 2006, published in Zashchita Metallov, 2006, Vol. 42, No. 6, pp.
627–631. 相似文献
996.
Yu. V. Alekseev G. Yu. Alekseev V. A. Bityurin A. V. Plaskeev 《Protection of Metals》2006,42(6):526-531
A simplified topokinetic dissolution model of a solid taking into account the correlation between the dissolution rate and
the atomic surface topography enables one to interpret a linear (in semilogarithmic coordinates) segment of the steady-state
curves of the active anodic dissolution of metals. Its slope corresponds to the product of a concentration of kinks and the
elementary reaction rate, both of which exponentially depend on the potential, rather than a simple (Tafel) elementary rate
of the atom dissolution at a semi-crystal kink.
Original Russian Text ? Yu.V. Alekseev, G.Yu. Alekseev, V.A. Bityurin, A.V. Plaskeev, 2006, published in Zashchita Metallov,
2006, Vol. 42, No. 6, pp. 568–573. 相似文献
997.
Z.M. Zhong J. Chen P. Zhong J.B. Wu 《The International Journal of Advanced Manufacturing Technology》2006,28(9):855-862
As the result of vibration emission in air, a machine sound signal carries important information about the working condition
of machinery. But in practice, the sound signal is typically received with a very low signal-to-noise ratio. To obtain features
of the original sound signal, uncorrelated sound signals must be removed and the wavelet coefficients related to fault condition
must be retrieved. In this paper, the blind source separation technique is used to recover the wavelet coefficients of a monitored
source from complex observed signals. Since in the proposed blind source separation (BSS) algorithms it is generally assumed
that the number of sources is known, the Gerschgorin disk estimator method is introduced to determine the number of sound
sources before applying the BSS method. This method can estimate the number of sound sources under non-Gaussian and non-white
noise conditions. Then, the partial singular value analysis method is used to select these significant observations for BSS
analysis. This method ensures that signals are separated with the smallest distortion. Afterwards, the time-frequency separation
algorithm, converted to a suitable BSS algorithm for the separation of a non-stationary signal, is introduced. The transfer
channel between observations and sources and the wavelet coefficients of the source signals can be blindly identified via
this algorithm. The reconstructed wavelet coefficients can be used for diagnosis. Finally, the separation results obtained
from the observed signals recorded in a semi-anechoic chamber demonstrate the effectiveness of the presented methods . 相似文献
998.
介绍了松辽流域水权初始分配中政府预留水量问题的系统研究。首先给出了政府预留水量的确定原则和预留优先级,然后提出一种政府预留水量双侧耦合分析方法,通过政府预留水量的需求与可能两个侧面,采用“自下而上”的预留需求与“自上而下”的可预留水量双侧耦合分水模式。通过大量的分析和计算,得出了松辽流域不同水平年、不同频率的政府预留水量。分析和应用结果表明,该方法是可行的,可为流域初始水权分配提供一种有效的技术方法。 相似文献
999.
1. Introduction Side-wall acoustic logging tools, such as the Segmented Bond Tool (SBT) from Baker Atlas and the tools for open hole measurements, utilize acoustic transducers mounted on six pads to make compensated acoustic velocity and attenuation measurements which are not affected by mud weight, gas cut, fast formation effects, casing surface conditions or reasonable tool de- centralizing. Studies on the wave fields generated by these tools are very important to tool design and data int… 相似文献
1000.
1. Introduction Seismic physical modeling technology is an important method for the research on seismic exploration theory and methods. In seismic physical experiments, the earth, mantle or field site are scaled down to physical models according to the similarity principle, and then the seismic field and its variation are observed in the laboratory for the research work on the theories and methods of the earth structure, earthquake forecasting, energy and mineral resource exploration, and engi… 相似文献