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41.
Callus cultures ofTheobroma cacao L., initiated from explants of immature cocoa bean cotyledons, contained 5.3%–6.4% lipids (dry wt basis). The major fatty
acids were palmitic, oleic and linoleic acids. Cell suspensions contained 5.7–7.7% total lipids which had a higher polyunsaturated
fatty acid content than total lipids of the calli. Phospholipids and glycolipids were the predominant lipid classes of calli
and cell suspensions. Immature cocoa beans at early stages of development contained much higher polyunsaturated fatty acids,
higher polar lipids and lower triglycerides than did mature ripe beans. Ripe cocoa beans contained 54% total lipids of which
96.8% where triglycerides. The fatty acid composition of total lipids of calli and cell suspensions were similar to those
of the immature cocoa beans. 相似文献
42.
The effect of recycle on heat (and mass) transfer in concentric circular tubes has been investigated by finite difference methods. Theoretical results show that recycle can enhance the heat transfer rate for large Graetz numbers compared with that in an open tube (without an inner tube inserted and without recycle). Competition between a preheating effect and a residence-time effect can be used to explain the heat transfer behavior. The heat transfer rate can be further augmented, with nearly no increase in total pressure drop, by employing flow pattern B instead of flow pattern A. 相似文献
43.
I.H. Farag S.B. Reddy Karri R. Breault K.Y. Tsai 《Chemical Engineering Communications》1986,48(4):331-348
The design of multistage fluidized beds for heat exchange necessitates the solution of the mass and energy balance equations combined with the equilibrium relations for each stage. This paper presents a novel way of applying well known methodology to a different technology, one where it has not been widely applied.
In the present work a McCabe-Thiele type of graphical approach is presented for both counter-current and cross-current contacting multiple fluidized beds. The necessary equations for a multistage calciner are developed and the application of the proposed method is demonstrated. Generalized fluidized bed efficiency for counter-current and cross-current multiple fluidized bed is presented. 相似文献
In the present work a McCabe-Thiele type of graphical approach is presented for both counter-current and cross-current contacting multiple fluidized beds. The necessary equations for a multistage calciner are developed and the application of the proposed method is demonstrated. Generalized fluidized bed efficiency for counter-current and cross-current multiple fluidized bed is presented. 相似文献
44.
An EGF-pseudomonas exotoxin A recombinant protein with a deletion in toxin binding domain specifically kills EGF receptor bearing cells 总被引:2,自引:0,他引:2
Lee Chi-Hon; Lee E-Ching; Tsai Shih-Tzer; Kung Hsing-Jien; Liu Yin-Chang; Hwang Jaulang 《Protein engineering, design & selection : PEDS》1993,6(4):433-440
We constructed two chimeric toxins; one composed of epidermalgrowth factor (EGF) and pseudomonas exotoxin A (PE), designatedEGF-PE and the other composed of EGF and PE with a deletionof the Ia domain (cell-binding domain), designated EGF-PE (Ia).Both chimeric toxins reacted with anti-EGF and anti-PE antibodies.The cell-killing experiments showed that EGF-PE, but not EGF-PE(Ia),was cytotoxic to the murine fibroblast cell line NR6, whichcarried the PE receptor, but not the EGF receptor. However,after NR6 was transfected with DNA for the expression of humanEGF receptor, the transfected cell line, designated NRHER5,overexpressed human EGF receptors and became sensitive to EGF-PE(IA).The cytotoxicity of EGF-PE(Ia), but not EGF-PE, to NRHER5 canbe completely blocked by an excess amount of EGF. To completelyreverse the cytotoxicity of EGF-PE on NRHER5, both the EGF receptorpathway and the PE receptor pathway need to be blocked. Theseresults suggest that EGF-PE exhibits both EGF and PE bindingactivities, while EGF-PE(IA) possesses only EGF binding activity.Thus, EGF-PE(Ia) may be a better chimeric toxin than EGF-PEin terms of target specificity to EGF receptor bearing cells.We, therefore, examined the cytotoxicity of EGF-PE(Ia) to varioushuman cancer cell lines. We find that human cancer cells containingmore EGF receptors are more sensitive to EGF-PE(Ia). 相似文献
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47.
The objective of this paper is to propose a novel press system with six links for precision deep drawing, and verify its feasibility. First, the system is presented and its advantages are discussed. Then, the kinematic analysis of the system is obtained by examining the geometry of the design. Moreover, kinematic dimensions of the variable coupling are found by using optimization method. Furthermore, the proposed approach is illustrated by a design example, its solid model for the proposed design is established, and then kinematic simulation is performed by ADAMS software. Finally, a prototype and an experimental setup are established, and the experiment is conducted. The results show that the proposed new mechanism is feasible and of reasonable accuracy. In addition, it has the advantages of easy manufacture, lower cost, higher precision, and easy adjustability. 相似文献
48.
Jason Tsai Emma Bowring Stacy Marsella Milind Tambe 《Autonomous Agents and Multi-Agent Systems》2013,27(2):200-217
In social psychology, emotional contagion describes the widely observed phenomenon of one person’s emotions being influenced by surrounding people’s emotions. While the overall effect is agreed upon, the underlying mechanism of the spread of emotions has seen little quantification and application to computational agents despite extensive evidence of its impacts in everyday life. In this paper, we examine computational models of emotional contagion by implementing two models (Bosse et al., European council on modeling and simulation, pp. 212–218, 2009) and Durupinar, From audiences to mobs: Crowd simulation with psychological factors, PhD dissertation, Bilkent University, 2010) that draw from two separate lines of contagion research: thermodynamics-based and epidemiological-based. We first perform sensitivity tests on each model in an evacuation simulation, ESCAPES, showing both models to be reasonably robust to parameter variations with certain exceptions. We then compare their ability to reproduce a real crowd panic scene in simulation, showing that the thermodynamics-style model (Bosse et al., European council on modeling and simulation, pp. 212–218, 2009) produces superior results due to the ill-suited contagion mechanism at the core of epidemiological models. We also identify that a graduated effect of fear and proximity-based contagion effects are key to producing the superior results. We then reproduce the methodology on a second video, showing that the same results hold, implying generality of the conclusions reached in the first scene. 相似文献
49.
Chun-Wei Tsai Shih-Pang Tseng Chu-Sing Yang Ming-Chao Chiang 《Applied Soft Computing》2013,13(6):3008-3020
This paper presents an effective and efficient method for speeding up ant colony optimization (ACO) in solving the codebook generation problem. The proposed method is inspired by the fact that many computations during the convergence process of ant-based algorithms are essentially redundant and thus can be eliminated to boost their convergence speed, especially for large and complex problems. To evaluate the performance of the proposed method, we compare it with several state-of-the-art metaheuristic algorithms. Our simulation results indicate that the proposed method can significantly reduce the computation time of ACO-based algorithms evaluated in this paper while at the same time providing results that match or outperform those ACO by itself can provide. 相似文献
50.
HOM4PS-2.0 is a software package in FORTRAN 90 which implements the polyhedral homotopy continuation method for solving polynomial systems. It updates its original version HOM4PS in three key aspects: (1) new method for finding mixed cells, (2) combining the polyhedral and linear homotopies in one step, (3) new way of dealing with curve jumping. Numerical results show that this revision leads to a spectacular speed-up, ranging up to 1950s, over its original version on all benchmark systems, especially for large ones. It surpasses the existing packages in finding isolated zeros, such as PHCpack (Verschelde in ACM Trans Math Softw 25:251–276, 1999), PHoM (Gunji et al. in Computing 73:57–77, 2004), and Bertini (Bates et al. in Software for numerical algebraic geometry. Available at http://www.nd.edu/~sommese/bertini), in speed by big margins. 相似文献