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21.
A novel all‐polymer light modulator with a gel‐in‐gel system was developed. The gel‐in‐gel system was constructed with colored gel particles responsive to stimuli held independently in another stimuli‐nonresponsive gel matrix. Well‐known thermoresponsive N‐isopropylacrylamide (NIPAM) gel particles containing a pigment were dispersed and fixed in an outer stimuli‐nonresponsive gel matrix. When poly(vinyl alcohol)–styrylpyridinium (PVA–SbQ) was used for the outer gel matrix, the light modulator showed excellent color‐changing properties because the PVA–SbQ matrix was selectively formed around the NIPAM gel particles and the particles exhibited a large volume change in the matrix. The temperature when the outer gel matrix was formed affected the haze of the light modulator. When the outer gel matrix was formed in the swollen state of the NIPAM gels, the haze of a light modulator increased with heating. On the contrary, the haze of a light modulator prepared in the shrunken state of the NIPAM gels decreased with heating. The response time of the color change was less than 1 s. The gel‐in‐gel system made a very fast macroscopic color change, taking advantage of the fast response of the micrometer‐sized gel particles. We believe that a light modulator with a gel‐in‐gel system may find various applications in optical devices. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2295–2303, 2007  相似文献   
22.
The purpose of this paper is to clarify the mechanism of planning failure on land use control in case of sprawl developments of large scale commercial facilities, which is often seen in many countries. The author demonstrates actual three cases in Japan: a huge commercial development established in the middle of rice field between the two local cities, two huge commercial accumulations established at the opposite fringes of urban area, and many large commercial developments established one by one within the small municipalities surrounding a central city. And by examining the statistical sales amount, the author describes that these huge suburban commercial developments apparently deprived the sales of the downtown. Through analyzing these cases, the author empirically stated that for the motorized local cites, the optimum location of commercial accumulation is no longer the central area of the city but about 15 min away from the center with the smooth accessible arterial road. At last, the author mentions that the "planning failure" could be occurred if the territory of planning authority and the scale of the development are inconsistent, such as the authority of small municipal government and the large scale commercial facility which impacts beyond the municipal boundary.  相似文献   
23.
The first part of this paper provides an overview of Computational Fluid Dynamics (CFD) modeling of snowdrift around a building by reviewing previous research including the authors’ in order to clarify its applicability and limitations. It is clarified that a quantitative validation study in particular by predicting snow depth distribution near a building is not enough, even though many models have been proposed. The latter part presents the results of CFD prediction of snowdrift around a cubic building model using a new approach of a snowdrift model based on experimental and numerical studies by the authors. The numerical results are compared with data obtained from detailed field measurements and previous CFD in order to confirm the accuracy of the new model. This new approach shows good correspondence with results obtained from field measurements and wind tunnel experiments in terms of not only snowdrift patterns but also quantitative distribution of snow depth.  相似文献   
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25.
Recently, windows with low-e double-glazing or heat-shading films often have been installed to the exterior surfaces of buildings to reduce the cooling load of the buildings. These windows specularly reflect solar radiation into pedestrian spaces. It has been pointed out that the increase in the incident solar radiation reflected at the windows degrades the thermal comfort levels of pedestrians. The installation of near-infrared rays retro-reflective film to window surfaces may both reduce the cooling load of the building and reduce the impacts on the thermal environment in outdoor spaces. Hence, it is expected that the installation of this film will counteract this problem and have positive effects. To assess the feasibility of installing retro-reflective materials to the exterior surfaces of the building walls and ground forming part of a city block, for improving the thermal environment in outdoor spaces, computational methods could serve as a powerful tool for analyzing the radiant environment in urban and building spaces. In this paper, a computational method is outlined for considering the directional reflections from the exterior surfaces of building walls and windows. The method is used to estimate the effects on the outdoor thermal comfort of pedestrians in the summer season.  相似文献   
26.
A remaining challenge in tissue engineering approaches is the in vitro vascularization of engineered constructs or tissues. Current approaches in engineered vascularized constructs are often limited in the control of initial vascular network geometry, which is crucial to ensure full functionality of these constructs with regard to cell survival, metabolic activity, and potential differentiation ability. Herein, the combination of 3D‐printed poly‐ε‐caprolactone scaffolds via melt electrospinning writing with the cell‐accumulation technique to enable the formation and control of capillary‐like network structures is reported. The cell‐accumulation technique is already proven itself to be a powerful tool in obtaining thick (50 µm) tissues and its main advantage is the rapid production of tissues and its ease of performance. However, the applied combination yields tissue thicknesses that are doubled, which is of outstanding importance for an improved handling of the scaffolds and the generation of clinically relevant sample volumes. Moreover, a correlation of increasing vascular endothelial growth factor secretion to hypoxic conditions with increasing pore sizes and an assessment of the formation of neovascular like structures are included.  相似文献   
27.
The developed desiccant-evaporative air-conditioning system was evaluated using the exergetic method under controlled environmental conditions to determine the performances of the whole system and its components.Percentage contributions of exergy destruction of system components at different regeneration temperatures and reference temperatures were determined. Exergy destruction coefficient of different components at different regeneration and reference temperatures were presented. It was shown that exergetic performances varied with respect to the regeneration and reference temperatures. The exergetic performances based on thermal, electric, total exergy input, first definition and second definition efficiencies were shown.Based on the results, reference and regeneration temperatures affected the determination of the system performances and its components. It was shown that air-heating coil, air fans and desiccant wheel contributed to large percentage of exergy destruction. Hence, the mentioned components should be given attention for further improvement of the system performances.  相似文献   
28.
Two types of polyelectrolyte multilayers were formed on both sides of a quartz crystal microbalance (QCM) substrate by a novel alternate drop coating process. In this study, poly(diallyldimethylammonium chloride) (PDDA) and poly(sodium 4-styrene sulfonate) (PSS) were used as strong-strong polyelectrolytes. On the other hand, PDDA and poly(acrylic acid) (PAA) were used as strong-weak polyelectrolytes. The novel alternate drop coating process can separately fabricate each polyelectrolyte multilayer on both sides of the substrate. The substrate provides dual biointerfaces, both sides of which comprise different multilayers, by employing a combination of polymers. The formation of the multilayer by alternate drop coating was evaluated in terms of changes in the frequency of the QCM and model protein adsorption for proteins such as bovine serum albumin, and their characteristics were investigated with those of the conventional alternate adsorption process by performing dip coating. There was no significant difference between the surface properties resulting from the two formation conditions. This result strongly supported the fact that the multilayers fabricated by alternate drop coating were similar in quality to those fabricated by conventional dip coating. The resulting dual biointerfaces with polyelectrolyte multilayers provide alternative biofunctions in terms of individual protein loading. In summary, the novel alternate drop coating process for substrates is a good candidate for the preparation of dual biointerfaces in the biomedical field.  相似文献   
29.
In emergency medical treatment of patients contaminated with radioactivity, air contamination control is very important to prevent the secondary contamination of medical staff. In order to optimize design of a greenhouse, a numerical analysis was made by using the Flow Designer software. As a scenario of air contamination, the breathing air of the patient was assumed to be highly contaminated with radioactive gaseous or particulate matter. It was found that air contamination strongly depended on the characteristics of the contaminants. The contamination map of the coarse aerosols with low diffusivity was quite different from those of the fine aerosols and gas. If the setting conditions of air-flow rate of the ventilation and the exhausting position were optimized, secondary contamination of the medical staff standing by the patient is prevented securely by a greenhouse.  相似文献   
30.
A 42-year-old man was admitted because of fever, productive cough, and progressive dyspnea. Chest x-ray films and computed tomographic scans disclosed dense consolidation in the left and right lung fields. No pathogenic agent was found despite extensive bacteriological examinations. Based on serological findings, the patient was given a diagnosis of acute pneumonia caused by Legionella micdadei. It has been reported that Legionnaire's disease is easily complicated by fatal systemic illnesses such as disseminated intravascular coagulation (DIC) and multiple organ failure. In fact, the patient suffered from severe hypotension and DIC on admission. Treatments against systemic complications were started together with intravenous administration of antibiotics including erythromycin. Continuous intravenous cathecolamin, however, failed to alleviate the patient's shock. We therefore applied endotoxin eliminating therapy using a polymyxin-B-column (PMX) and continuous hemofiltration (CHF). The patient recovered from critical shock immediately after the start of PMX, which together with CHF, alleviated his systemic complications. Although the factors responsible for fatal systemic complications in Legionnare's disease are not well-documented, our findings suggested that some substances removable by PMX and CHF play an important role in pathogenesis.  相似文献   
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