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381.
A series of ethylene vinyl acetate copolymers (EVA) were blended with some tackifier resins that are made from wood extracts, and possible relations between their miscibility and properties as hot‐melt adhesives (HMA) were investigated. From our previous report on miscibility of various EVA‐based HMAs, we chose some blends that represent some of typical miscibility types and measured their adhesive tensile strengths. When the blends were miscible at testing temperatures, the temperature at which the maximum value of adhesive tensile strength was recorded tended to move toward higher temperature as tackifier content of blends increased. This result corresponds to the glass transition temperature (Tg) of the blends that became higher as tackifier content of blends increased when blend components were miscible. In terms of HMA performances, we suggest that factors other than miscibility affect absolute values of adhesive tensile strength more directly than miscibility; this idea has to be investigated further in a future study. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 719–725, 2002  相似文献   
382.
This paper describes the development of a robotic CAM system for an articulated industrial robot RV1A from the view point of robotic servo controller. It is defined here that the CAM system includes an important function which allows an industrial robot to move along cutter location data (CL data) consisting of position and orientation components. In addition, the developed CAM system has a high applicability to other industrial robots whose servo systems are technically opened to end-users. The developed robotic CAM system works as a straightforward interface between a general CAD/CAM and an industrial robot. At the present stage, the relationship between CAD/CAM and industrial robots is not well established compared to NC machine tools that are widely spread in manufacturing industries. The CAM systems for NC machine tools are already established, however, the CAM system for industrial robots has not been sufficiently considered and developed yet. A teaching pendant is generally used to obtain position and orientation data of the arm tip before an industrial robot works. Here, in order to enhance the relationship between a conventional CAD/CAM system and an industrial robot, a simple and straightforward CAM system without using any robot language is developed and implemented. The basic design of the robotic CAM system and the experimental results are presented in this paper.  相似文献   
383.
The effects of Ni content, soldering temperature and time on the IMC thickness in Sn-3Ag-0.5Cu and Sn-3Ag-0.5Cu-0.2Co alloys were researched using uniform design method and computer programs. For each alloy, the factors were divided into three levels in the experiment. Two correlative equations are given by regression. They indicate that the effects of three factors on the function are in the mutual and quadratic forms. And the analysis of variance shows the equations are sound and meaningful. Using the equations, it is easy to search, predict and control the IMC thickness. The existence of element Co accelerates the crystallization and growing up oflMC.  相似文献   
384.
Syringomycin-E (SE) was significantly lethal to Aspergillus and Fusarium species at between 1.9 and 7.8 micrograms/ml. SE complexed with the following fungal wall constituents (in order of binding): beta-1,3-glucan > chitin > mannan > ergosterol = cholesterol. Cytotoxicity in HeLa cells was proportional to the SE concentration, while the amount required for cytotoxicity was 3 to 20 times that needed to kill 95% of the fungi tested.  相似文献   
385.
The transmission performances of a random metal-dielectric film composed of silver metal and spherical fused silica balls were experimentally investigated for intensity- and frequency-modulated optical signals. The film was formed on the facet of a laser diode, and intensity-modulated optical signals emitted from the laser diode were successfully transmitted through it. Frequency-modulation optical signals were successfully detected by using an optical heterodyne technique. These results indicate that this random metal-dielectric film is well suited for use as a waveguide for optical signal transmission.  相似文献   
386.
387.
Polycrystalline Si (poly-Si) films formed by flash lamp annealing of precursor a-Si films on glass substrates have periodic surface roughness spontaneously formed through crystallization, which effectively acts to decrease optical reflection. The surface roughness initially decreases, and then reversely increases with increase in the duration of wet etching, performed to modulate the surface morphology and to reduce optical reflectance. This curious phenomenon can be understood as the selective removal of surface projections, which contain a number of voids, and as different etching rates of large-grain and fine-grain regions. The antireflection effect is enhanced not by the variation of the surface roughness, but rather by the removal of the voids near the surface. The etched poly-Si films covered with antireflection films show remarkably low average reflectance of 3% without any complicated texturing processes, which will lead to the fabrication of high-efficiency solar cells by a simple process.  相似文献   
388.
Various biological reaction models have been proposed which estimate concentrations of soluble and insoluble components in effluent of sewage treatment plants. These models should be effective to develop a better operation system and plant design, but their formulas consist of nonlinear equations, and there are many model constants, which are not easy to calibrate. A technique has been proposed to decide the model constants by precise experiments, but it is not practical for design engineers or process operators to perform these experiments regularly. Other approaches which calibrate the model constants by mathematical techniques should be used. In this paper, the optimal regulator method of modern control theory is applied as a mathematical technique to calibrate the model constants. This method is applied in a small sewage treatment testing facility. Calibration of the model constants is examined to decrease the deviations between calculated and measured concentrations. Results show that calculated values of component concentrations approach measured values and the method is useful for actual plants.  相似文献   
389.
390.
Recently, the task of planning in power systems is becoming a very complicated process for utility planners. This kind of planning has many objectives to accomplish. This paper employs the negotiation algorithm, which was proposed by the Chen-Ching Liu group for subtransmission power system planning to create a plan having many objectives. First, the goal-decision network (GDN) is constructed to model this planning problem, and the negotiation algorithm is applied to utilize both subtransmission system planning GDN, which attempts to capture its knowledge, and negotiation operators, which search for the most feasible and promising decisions in this planning GDN. Finally, the negotiation expert system is demonstrated for the subtransmission system planning using a real system.  相似文献   
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