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91.
This article describes high intellectual and creative educational multimedia technologies (HICEMTs), which will constitute one of the innovative breakthroughs in science and technology of the 21st century and will lead to a new wave of innovations in psychology. HICEMTs appear at the intersection of many subdisciplines of psychology (including general, cognitive, developmental, educational, personality, media, cyber, and applied), education, and multimedia. The general and specific nature of HICEMTs is considered. The importance of HICEMTs is discussed from technological, economic, societal, educational, and psychological perspectives. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
92.
Despite science's great intellectual prestige, developing robot scientists will probably be simpler than developing general AI systems because there is no essential need to take into account the social milieu.  相似文献   
93.
    
The aim of this study was to provide important insights into the effects of four different dental polishing protocols (one single‐step and one multi‐step either followed or not by diamond paste polishing) on the 3D surface morphology of two representative dental resin‐based nanocomposites (a nanofilled and a nanohybrid composite) by means of digital image analysis and processing techniques. The 3D surface morphology was investigated by atomic force microscopy. Segmentation, statistics of height distributions (described by statistical parameters, according to ISO 25178‐2: 2012) and Minkowski functionals were applied to the images to characterize the spatial patterns of analyzed samples at micrometer scale. The nanofilled composite had significantly lower values of height parameters in comparison with nanohybrid one. Multi‐step polishing protocol generated a statistically significant smoother finish for both tested materials, than one‐step polishing protocol, even when it was followed by diamond paste polishing. Diamond paste polishing generated a statistically significant smoother surface of tested samples. This suite of surface analysis tools is important in the research and manufacture of these dental resin‐based nanocomposites, where material surfaces have a key role in the functionality of objects.  相似文献   
94.
Enterprises and service providers are increasingly challenged with improving the quality of service delivery while containing the cost. However, it is often difficult to effectively manage the complex relationships among dynamic customer workloads, strict service level requirements, and efficient service management processes. In this paper, we present our progress on building autonomic systems for IT service management through a collection of automated data driven methodologies. This includes the design of feedback controllers for workload management, the use of simulation-optimization methodology for workforce management, and the development of machine learning models for event management. We demonstrate the applicability of the presented approaches using examples and data from a large IT service delivery environment.  相似文献   
95.
We have studied the density and structure of specimens of the alloy WC – 24 mass% Ni, obtained by combining into one step the processes of synthesis of the metallic phase and compaction of the ultrafine mixture of WC – Ni powders by high-energy pressing and sintering. We have established that reduction of nickel monoxide by carbon occurs at temperatures of 650-750°C and does not affect the shrinkage process which in the case of sintering begins only at a temperature of 1050°C. High-energy pressing of briquettes sintered at the indicated temperature reduces their porosity from 30-25% down to 8-4%. Specimens of porosity <1% can be obtained by pressing at 1150°C or 1050°C in the case of triple pressing. Raising the temperature at which the briquettes are heated is accompanied by enlargement of the pores together with a decrease in the total porosity, but at temperatures of 1300°C (sintering) and 1250°C (pressing), the pore dimensions are sharply reduced. The high density of the specimens pressed at low temperature does not provide low electrical resistance, which suggests the presence of weakly connected boundaries. When the specimens are sintered and pressed in the solid phase, we observe the growth of tungsten carbide particles. It is most rapid at 1150-1250°C, while at 1050°C the particle growth process slows down. Reduction of the metal oxide when the powders are heated promotes formation of structure in the higher temperature range.  相似文献   
96.
Mechanical properties of WC–24 mass% Ni alloy prepared by a combination in single stage of metal phase synthesis and compaction of an ultrafine mixture of WC–Ni powders by high-energy compaction and sintering are studied. Tungsten carbide, nickel oxide, and carbon are selected as the starting powders. After milling the initial powders the average particle size is 200-300 nm. Previously compacted briquettes of WC + NiO + C are heated, sintered, and pressed in the range 950-1300°C at vacuum of 0.133 Pa. Briquettes are also sintered in the liquid phase at 1350°C for comparison. Ultimate strength in bending, fracture toughness, ultimate strength in compression, and Vickers hardness are determined for specimens prepared at different temperatures. The dependence of mechanical properties on specimen consolidation temperature is studied. It is shown that these dependences for pressed specimens have a maximum at 1200-1250°C. The high level of properties (ultimate strength in bending 2500 MPa, ultimate strength in compression 3100 MPa, fracture toughness 19 MPa·m1/2, and hardness 10.0 GPa) are achieved for a WC + Ni + C powder mixture to which carbon is added in the form of a liquid carbon-containing compound. Introduction into the mixture of commercial carbon grade P803 leads to low specimen mechanical properties. The effect on mechanical properties of porosity and pore size, and also grain boundary quality between particles is studied.  相似文献   
97.
A family of Composites “Salt inside Porous Matrix” (CSPM) has been considered as promising for adsorption heat transformation (AHT) due to their high sorption capacity, steep sorption isobars and opportunity to harmonize CSPM properties with boundary conditions of the AHT cycle. In this communication, we extend the harmonizing tools by confinement of one more salt to the matrix pores. Novel CSPMs based on a binary mixture of lithium, calcium, and barium halides inside various mesoporous matrices were synthesized with wide variation of the relative salts content. Their phase composition and sorption equilibrium with water, methanol and ammonia vapour were studied by XRD and TG techniques. It was shown that the formation of a homogeneous solid solution of the salts led to changing the equilibrium temperature (pressure) of the solvation. Thus, the confinement of binary salt systems to the matrix pores can be an effective tool for designing innovative materials with predetermined sorption properties adapted to particular AHT cycles.  相似文献   
98.
    
It is demonstrated that the orientation of striped patterns can be reversibly switched between two perpendicular in‐plane orientations upon exposure to electric fields. The results on thin films of symmetric polystyrene‐block‐poly(2‐vinyl pyridine) polymer in the intermediate segregation regime disclose two types of reorientation mechanisms from perpendicular to parallel relative to the electric field orientation. Domains orient via grain rotation and via formation of defects such as stretched undulations and temporal phase transitions. The contribution of additional fields to the structural evolution is also addressed to elucidate the generality of the observed phenomena. In particular solvent effects are considered. This study reveals the stabilization of the meta‐stable in‐plane oriented lamella due to sequential swelling and quenching of the film. Further, the reorientation behavior of lamella domains blended with selective nanoparticles is addressed, which affect the interfacial tensions of the blocks and hence introduce another internal field to the studied system. Switching the orientation of aligned block copolymer patterns between two orthogonal directions may open new applications of nanomaterials as switchable electric nanowires or optical gratings.  相似文献   
99.
    
Two-photon direct laser writing enables the fabrication of shape-changing microstructures that can be exploited in stimuli responsive micro-robotics and photonics. The use of Liquid Crystalline Networks (LCN) allows to realize 3D micrometric objects that can contract along a specific direction in response to stimuli, such as temperature or light. In this paper, the fabrication of free-standing LCN microstructures is demonstrated as graphical units of a smart tag for simple physical and optical encryption. Using an array of identical pixels, information can be hidden to the observer and revealed only upon application of a specific stimulus. The reading mechanism is based on the shape-change of each pixel under stimuli and their color that combine together in a two-level encryption label. Once the stimulus is removed, the pixels recover their original shape and the message remains completely hidden. Therefore, an opto-mechanical equivalent of an “invisible ink” is realized. This new concept paves the way for introducing enhanced functionalities in smart micro-systems within a single lithography step, spanning from storage devices with physical encryption to complex motion actuators.  相似文献   
100.
    
Nanocomposite materials have been thoroughly exploited in additive manufacturing, as a means to alter physical, chemical, and optical properties of resulting structures. Herein, nanocomposite materials suitable for direct laser writing (DLW) by two-photon polymerization are presented. These materials, comprising silica nanoparticles, bring significant added value to the technology through physical reinforcement and controllable photonic properties. Incorporation into acrylate photoresists, via a one-step fabrication process, enables the formation of complex structures with large overhangs. The inclusion of 150 nm silica nanoparticles in DLW photoresists at high concentrations, allows for the fabrication of composite microstructures that show reflected color, a product of the relative contributions from the quasi-ordering and random scattering. Using common DLW design parameters, such as slicing distance and structure dimension, a wide gamut of structural color, in solution, using a set concentration of nanoparticles is demonstrated. Numerical modeling is employed to predict the reflected wavelength of the pixel arrays, across the visible spectrum, and this information is used to encode reflected colors into different pixel arrays.  相似文献   
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