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1.
Territorial Impact Assessment (TIA) is proposed as a critical tool in order to investigate the way policies affect spatial development and hence territorial cohesion. The paper introduces a TIA methodological model in relation to transport sector. The design of the methodological model is based on a quantitative evaluation framework that comprises a set of selected indicators applied in a cross-border area of southeast Europe, influenced by the operation of the Greek motorway system of Egnatia and its vertical axes. The indicators are grouped into three main fields of TIA, i.e. transport intermodality, polycentric spatial organization and cross-border territorial cooperation. The TIA’s indicators are approximated by quantitative analysis. The procedure concludes to an overall composite indicator measuring the ‘level of territorial cohesion’ along with some core results and the expected added value. It also highlights some key technical aspects about the routines used and proceeds to suggestions for further refinement.  相似文献   
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The public acceptance of biofuels in Greece is examined in this work. The analysis of 571 face to face interviews shows that 90.7% of the respondents believe that climatic changes are related to fossil fuel consumption, while only 23.8% know the difference between biodiesel and bioethanol. 76.1% believe that energy saving should precede the use of an alternative source of energy. Only 27.3% believe that priority must be given to biofuels over other renewable energy sources. Only 49.9% think that the use of biofuels can be an effective solution against climatic changes and 53.9% believe that the use of biofuels can be an effective solution for the energy problem. Finally, 80.9% of the car owners are willing to use biofuels, 44.8% are willing to pay the supplementary amount of 0.06 €/L of the fuel market price, while the average amount reported as willing to pay was 0.079 €/L on top of the fuel market price. Furthermore, eight models correlating the eight main responses with several socioeconomic variables are developed and analyzed. Those findings heave important policy implications related to the use and promotion of biofuels.  相似文献   
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Impact of climate change alone and in combination with currently planned emission control strategies are investigated to quantify effectiveness in decreasing regional ozone and PM2.5 over the continental U.S. using MM5, SMOKE, and CMAQ with DDM-3D. Sensitivities of ozone and PM2.5 formation to precursor emissions are found to change only slightly in response to climate change. In many cases, mass per ton sensitivities to NO(x) and SO2 controls are predicted to be greater in the future due to both the lower emissions as well as climate, suggesting that current control strategies based on reducing such emissions will continue to be effective in decreasing ground-level ozone and PM2.5 concentrations. SO2 emission controls are predicted to be most beneficial for decreasing summertime PM2.5 levels, whereas controls of NO(x) emissions are effective in winter. Spatial distributions of sensitivities are also found to be only slightly affected assuming no changes in land-use. Contributions of biogenic VOC emissions to PM2.5 formation are simulated to be more important in the future because of higher temperatures, higher biogenic emissions, and lower anthropogenic NO(x) and SO2 emissions.  相似文献   
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We simulate the amorphous–crystal interface in silicon using a combination of interatomic potential molecular-dynamics and tight- binding conjugate-gradient relaxation. The samples we create have high quality crystalline and amorphous portions. We develop some localized measures of order to characterize the interface, including a missing neighbor vector and the bond angle deviation. We find that the measures of order interpolate smoothly from a bulk crystal value to a bulk amorphous value across a 7 Å thick interface region. The interface structures exhibit a number of interesting features. The crystal planes near the interface are nearly perfect, with a few dimer defects similar to the Si(100) 2×1 reconstruction. Interfaces produced with one constant temperature simulation method are rough, with several layers of atoms forming <110> chains and (111) facets. A different simulation method produces more planar interfaces with only a few <110> chains.  相似文献   
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The energetically preferred structures of group V adsorbate monolayers on Si and SiGe substrates were studied using first-principles total energy calculations. By comparing structural features of the optimal adsorbate geometries we infer that structures involving self-bonded adsorbate units, such as dimers, trimers or chains, are most likely to segregate easily during growth. Among the group V elements considered, Sb forms structures involving self-bonded adsorbate units on the substrates considered, making it the most promising candidate for a surfactant. This prediction is consistent with recent experiments on Si(111) homoepitaxy. We also consider a simple solid-on-solid model that captures the essential features of surfactant behavior on Si substrates. The model involves a single variable a, the activation energy for exchange between a newly deposited atom and a surfactant unit on a terrace. We find that depending on the temperature, the model leads to smooth or rough overlayers. The transition takes place at kBT 0.1 a. The qualitative difference in growth mode is demonstrated by examining the topological features of films grown under different conditions.  相似文献   
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An integrated approach of the design and optimization problem of reinforced concrete frames, based on the use of interactive computer graphics is presented. The formulation of the optimization problem in terms of all the design variables and constraints is given. The size of the problem is greatly reduced if reinforcement areas are considered as dependent variables. A fully stressed design method is employed to optimize an automatically generated initial design. Analysis and design results plots, including complete reinforcement drawings, are available to designers, helping them to evaluate the current status of the design and allowing them to direct the entire computation process.  相似文献   
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The permeability coefficients (P) of linalool, citral ethyl butyrate, d-limonene and octanal permeating through LDPE and ionomer films were measured alone as individual and as a component of a mixture at a temperature of 23 °C and in saturated water vapour. Values of P for ionomer film were approximately two orders of magnitude below those for LDPE for the compounds tested. Both PET and PETG films were found to be much better barriers against the compounds tested than LDPE and ionomer films. In general, the permeability, diffusion and solubility coefficients (P. D, and S) values measured in mixture were substantially less than the values obtained individually. Permeability behaviour of these compounds at low concentrations in the mixture was similar to that of permanent gases. Reduction of solubility coefficients in mixture permeation was greater with the higher solubility coefficients. These results provide a better understanding of the mechanism of vapour diffusion through polymers.  相似文献   
9.
Wang WL  Meng S  Kaxiras E 《Nano letters》2008,8(1):241-245
We investigate, using benzenoid graph theory and first-principles calculations, the magnetic properties of arbitrarily shaped finite graphene fragments to which we refer as graphene nanoflakes (GNFs). We demonstrate that the spin of a GNF depends on its shape due to topological frustration of the pi-bonds. For example, a zigzag-edged triangular GNF has a nonzero net spin, resembling an artificial ferrimagnetic atom, with the spin value scaling with its linear size. In general, the principle of topological frustration can be used to introduce large net spin and interesting spin distributions in graphene. These results suggest an avenue to nanoscale spintronics through the sculpting of graphene fragments.  相似文献   
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