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91.
The relevance of bargaining to everyday life can easily be ascertained, yet the study of any bargaining process is extremely hard, involving a multiplicity of questions and complex issues. The objective of this paper is to provide new insights on some dimensions of the bargaining process-asymmetries and uncertainties in particular-by using a non-cooperative game theory approach. We develop a computational model which simulates the process of negotiation among more than two players, who bargain over the sharing of more than one pie. Through numerically simulating several multiple issues negotiation games among multiple players, we identify the main features of players’ optimal strategies and equilibrium agreements. As in most economic situations, uncertainty crucially affects also bargaining processes. Therefore, in our analysis, we introduce uncertainty over the size of the pies to be shared and assess the impact on players’ strategic behaviour. Our results confirm that uncertainty affects players’ behaviour and modify the likelihood of a self-enforcing agreement to emerge. The model proposed here can have several applications, in particular in the field of natural resource and environmental management at the national or local level, where conflicts over how to share a resource of a finite size are increasing.  相似文献   
92.
This paper presents a quantitative comparison of the dichlorodimethylsilane (DDMS) monolayer to the octade-cyltrichlorosilane (OTS) self-assembled monolayer (SAM) with respect to the film properties and their effectiveness as anti-stiction coatings for micromechanical structures. Both coatings have been evaluated in several ways, including atomic force microscopy (AFM), contact angle analysis (CAA), work of adhesion by cantilever beam array (CBA) technique and coefficient of static friction using a sidewall testing device. While water and hexadecane contact angles are comparable, the DDMS coated microstructures exhibit higher adhesion than OTS coated ones. Furthermore, coefficient of static friction data indicate that the DDMS films are not as effective at lubrication as the OTS SAMs are, although both exhibit much improvement over chemical oxide. However, AFM data show that the samples which receive DDMS treatment accumulate fewer particles during processing than those which receive the OTS SAM treatment. The thermal stability of the DDMS film in air far exceeds the OTS SAM, as the DDMS remains very hydrophobic to temperatures upwards of 400°C  相似文献   
93.
Suspended mechanical structures based on elastic silicon nanowire arrays   总被引:1,自引:0,他引:1  
We demonstrate a bottom-up/top-down combined method for the fabrication of horizontally suspended, well-oriented and size-controlled Si nanowire arrays. Mechanical beamlike structures composed of multiple ordered arrays consecutively linked by transversal microspacers are obtained by this method. Such structures are used to investigate the mechanical elasticity of the nanowire arrays by atomic force microscopy. Our results point out important differences in the morphology and mechanical behavior of the fabricated nanowire-based structures with respect to equivalent bulk material structures.  相似文献   
94.
The resonance frequency of AFM cantilevers depends on the elastic modulus and on the dimensions of the cantilever. As for coated cantilevers, the resonance frequency will be determined not only by the properties of the cantilever, but also by the properties of the coating (elastic modulus and thickness). We have carried out a systematic investigation of cantilevers coated with several thicknesses of the DLC films. Measurements of the resonance frequency of the cantilevers, before and after the DLC coating, were used with a model to determine the elastic modulus of the DLC. The elastic modulus obtained for the DLC, with this model, was E2=616 GPa. The AFM tip radii were also measured after coating and were found to increase with the DLC film thickness.  相似文献   
95.
Magnetic Fe3O4 (magnetite) nanoparticles are synthesized via a chemical precipitation route in different alkaline environments (NH3 or NaOH) and subsequently functionalized with a (propynylcarbamate)triethoxysilane moiety, with the aim of promoting the nucleation and subsequent stabilization of gold nanoparticles. The propynylcarbamate group is able to capture the gold precursor (HAuCl4), spontaneously reduce it, and stabilize the resulting Au nanoaggregates. The obtained results show that though the dimensions of the starting magnetite substrate depend on the base used in the preparation, they remain unaltered upon the subsequent modification. Conversely, the average Au nanoparticle dimensions can be conveniently tailored as a function of the base used in Fe3O4 preparation and the presence/absence of the organic functionalization. The smallest dimensions (15?nm) are obtained for AuNP supported on propynylcarbamate-functionalized Fe3O4 prepared in the presence of ammonia. Magnetization measurements highlight that all the Au/Fe3O4 nanocomposites display a superparamagnetic behavior and those obtained using ammonia showed consistently smaller Hc and Mr values (av. values of 7.4?Oe and 0.8?emu/g) than those prepared with sodium hydroxide (av. values of 28?Oe and 2.8?emu/g).  相似文献   
96.
The combination of W and SiC has many applications such as a hot cell of a thermionic energy converter, nuclear material, and high temperature microelectronics. In this study, a 2 µm thick TiN film is introduced as a diffusion barrier between SiC and W to avoid the inter-diffusion reaction at high temperature. The effect of annealing temperature on the surface morphology and microstructure of the TiN film is studied to explore its high temperature stability. Then 500 nm W film is sputtered on the TiN film to characterize the inter-diffusion and stability of the W/TiN/SiC multilayer at 1100°C by XRD, Raman spectroscopy and cross-sectional EDS mapping techniques. The results indicate that the W/TiN/SiC multilayer is very stable even when heated at 1100°C for 25 hours.  相似文献   
97.
Calcite-based composite scaffolds have been successfully 3D-printed by direct ink writing, starting from a paste comprising a silicone polymer and calcite (CaCO3) powders. The firing in nitrogen, at 600?°C, after preliminary cross-linking step at 350?°C, determined the transformation of the polymer matrix into a silica-carbon nano-composite, embedding unreacted calcite particles. Compared to previously developed silica-calcite scaffolds, obtained after firing in air, the new composites exhibited a significant strength improvement (up to ~10?MPa, for a total open porosity of 56%). The new formulation did not compromise the in vitro bioactivity and the biocompatibility of the scaffolds, as shown by dissolution studies in SBF and preliminary cell culture tests, with human fibroblasts. Due to the simplicity of the processing and the outstanding mechanical performances, the developed scaffolds are promising candidates for bone tissue engineering applications.  相似文献   
98.
This paper addresses two basic issues related to technological innovation and climate stabilization objectives: can innovation policies be effective in stabilizing climate? To what extent can innovation policies complement carbon pricing (taxes or permit trading) and improve the economic efficiency of a mitigation policy package? To answer these questions, we use an integrated assessment model with multiple externalities and an endogenous representation of the technical progress in the energy sector. We evaluate a range of innovation policies, both as stand-alone and in combination with other mitigation policies. Our analysis indicates that innovation policies alone are unlikely to stabilize global concentration and temperature. As for the benefits of combining climate and innovation policies, we find efficiency gains of 10% (6 USD Trillions in net present value terms) for a stringent climate policy, and 30% (3 USD Trillions) for a milder one. However, such gains are reduced when more plausible (sub-optimal) global innovation policy arrangements are considered.  相似文献   
99.
The intriguingly complex glomerular podocyte has been a recent object of intense study. Researchers have sought to understand its role in the pathogenesis of common proteinuric diseases such as minimal change disease and focal segmental glomerular sclerosis. In particular, considerable effort has been directed towards the anatomic and functional barrier to macromolecular filtration provided by the secondary foot processes, but little attention has been paid to the potential of podocytes to handle plasma proteins beyond the specialization of the slit diaphragm. Renal membrane transporters in the proximal tubule have been extensively studied for decades, particularly in relation to drug metabolism and elimination. Recently, uptake and efflux transporters for small organic molecules have also been found in the glomerular podocyte, and we and others have found that these transporters can engage not only common pharmaceuticals but also injurious endogenous and exogenous agents. We have also found that the activity of podocyte transporters can be manipulated to inhibit pathogen uptake and efflux. It is conceivable that podocyte transporters may play a role in disease pathogenesis and may be a target for future drug development.  相似文献   
100.
Fe (III)-loaded chitosan (CS) hollow fibers (CS-Fe (III) HF) were successfully prepared according to the dry-wet spinning technique. The CS-Fe (III) HFs were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and thermal gravimetric analysis (TGA). Removal of pentavalent arsenic was studied through biosorption on CS-Fe (III) HF adsorptive membranes. The response surface methodology (RSM) was applied to investigate the influence of the main operating parameters such as contact time, pH, initial As (V) concentration and HFs dosage on the adsorption capacity of As (V). From the Pareto analysis, pH, [As (V)]o, [CS-Fe (III) HF membranes] and squared effect of [As(V)]o were found to produce the largest effect on biosorption of As (V). Kinetic studies showed that the pseudo-second-order kinetic model provides the best correlation to the experimental results. Equilibrium data fitted well with the Langmuir model with maximum adsorption capacity of 3,703 μg g?1. A laboratory scale glass membrane module consisting of three CS-Fe(III) HFs has also been prepared and tested for biosorption of As (V) at a real scale. Permeability of As (V) ions through the CS-Fe (III) HF membranes was 0.145 μmol m?2 h?1 bar ?1.  相似文献   
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