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821.
A field survey was carried out in order to collect, elaborate and analyse data concerning the actual energy consumption for space heating of a sample of about 140 buildings (120 high schools) in the Province of Torino (Italy). 相似文献
822.
823.
Vincenzo Gente Floriana La Marca Paolo Massacci Silvia Serranti 《Particulate Science and Technology》2007,25(5):481-494
Worldwide legislation coming into force requires considering new waste streams in order to achieve higher targets for material recovery and recycling. It is necessary, therefore, to manage waste materials in which different components are linked together and contaminants of various origins are present. Waste materials thus need to be treated that have a complex and often unknown composition and present different structural, morphological, and chemical properties. The physical and chemical characterization of solid waste is an essential step for the development of suitable treatment strategies, aimed at the recovery of one or more waste components. Scanning electron microscopy appears to be in most cases very helpful for waste characterization, providing information on material size, shape, structure, texture, distribution, and composition. Examples of waste characterization through scanning electron microscopy, finalized to material recovery, are reported. The waste materials taken into consideration include solids of different nature, such as spent lead batteries, cathode ray tubes (CRT), and printed circuit boards (PCB). 相似文献
824.
825.
Increasing interest is currently being addressed to multi-energy systems in buildings. These systems integrate different energy sources, at least one of which is renewable, in order to cover the thermal and electrical loads of a building. Since the design and operation of such systems are very complicated for many reasons (e.g. the intermittent nature of the renewable sources, the highly interlinked system layouts), it is of the foremost importance to provide tools to help select the best system configuration and energy sources mix.A modelling approach to multi-energy systems in buildings, based on the energy hub concept is presented in this work. This approach allows the coupling between the energy demand and the energy supply in a building to be modelled in a synthetic way. The model was customised to be used at the concept stage of the building design, either as a system simulation tool or as a system selection tool. If the prices and the characteristics of the energy converters and of the energy-wares are known, it is possible, with a certain set of constraints, to determine the configuration that minimises the initial investment costs, the use of non-renewable sources or the life-cycle costs. This approach makes it possible to avoid the simulation and ranking of a set of different system configurations, and also permits the study of the behaviour of such systems in an open configuration and not as individual systems. An application of the methodology to a case study is provided. 相似文献
826.
Paolo Cabras Alberto Angioni Vincenzo L. Garau Filippo M. Pirisi Franco Cabitza Mario Pala 《Food Additives & Contaminants》2000,17(10):855-858
Field trials were carried out to study the persistence of acephate and buprofezin on olives. Two cultivars, pizz'e carroga and pendolino, with very large and small fruits respectively were used. After treatment, no difference was found between the two pesticide deposits on the olives. The disappearance rates, calculated as pseudo first order kinetics, were similar for both pesticides (on average 12 days). Methamidophos, the acephate metabolite, was always present on all olives, and in some pendolino samples it showed higher residues than the maximum residue limit (MRL). During washing, the first step of olive processing, the residue level of both pesticides on the olives did not decrease. After processing of the olives into oil, no residues of acephate or methamidophos were found in the olive oil, while the residues of buprofezin were on average four times higher than on olives. 相似文献
827.
A two-step ion-exchange process that introduces strengthening and multiple cracking into glasses has been developed. The experimental parameters in the second step must be carefully controlled to avoid spontaneous cracking, because the compressive stress is reduced in the surface region. Control of the near-surface stress gradient is an important role of the second ion-exchange step. Double ion exchange leads to strength values as high as those that are obtained after the first ion-exchange step but remarkably produces multiple cracking on the specimen surface on loading. The multiple cracking, which acts as a failure warning, is initiated at 300 MPa, and the crack spacing decreases as the applied stress increases. The multiple cracking is shown to be a result of the crack stability that is induced by the designed residual-stress profiles. This behavior has been confirmed, using the measured residual stresses to calculate the apparent-toughness curves for surface cracks. The duration of the first ion-exchange step has been shown to be important in determining the degree of strengthening; however, the duration of the second step controls the extent of the crack stability. 相似文献
828.
Fabrizio Quadrini Loredana Santo Vincenzo Tagliaferri Federica Trovalusci 《Polymer Engineering and Science》2006,46(7):896-903
Plastic shaping was performed by means of the combination of IR heating and pellet softening in a semitransparent open mold. Three commercial thermoplastic materials were employed (acrylonitrile‐butadiene‐styrene, polyethylene, and polypropylene) and process curves were extracted depending on IR lamp power and interaction time. A simple exponential model was defined for the prediction of molded sample thickness and a master curve was built for all the materials. A scale factor was introduced depending on the IR lamp power and not on the material. Besides, the density of molded sample was monitored, obtaining in such conditions density values comparable to typical injection molded ones, even if a very low load was applied during pellet molding (10 N). POLYM. ENG. SCI., 46:896–903, 2006. © 2006 Society of Plastics Engineers 相似文献
829.
S Scardi C Pandullo C Mazzone D Goldstein M Zecchin 《Canadian Metallurgical Quarterly》1996,26(3):273-285
When ES-5 cells were transfected with an exogenous porcine TGF-beta 1 gene, one can obtain clones of genetically modified ES cells with over-expression of the transfected gene. We called the genetically modified ES-5 cells as ES-T cells. When ES-T cells were used to study their differentiation in vitro by all trans-retinoic acid (RA), it was soon noticed that embryoid bodies of ES-T cells can exclusively differentiate into endothelial cells and vessel-like structures, but not in their parent ES-5 cells. The above result is the first indication that the differentiation of tubular structures in embryoid bodies of ES-T cells may somehow be related to TGF-beta 1. To demonstrate further the role of TGF-beta 1 in the formation of vessel-like structures, the cultured ES-5 cells in the presence of added rhTGF-beta 1 were closely followed in the course of their differentiation. We have, thus, demonstrated the promoting effects of exogenous rhTGF-beta 1 in the formation of vessel-like structures, morphologically similar to those structures derived from ES-T6 cells, during the differentiation of ES-5 cells, both in monolayer culture, in three dimensional collagen gel and in embryoid bodies cultured on gelatin-coated tissue culture wells. Addition of suitable amount of anti-TGF-beta 1 monoclonal antibody IgG (TB21) to the culture medium of embryoid bodies of ES-T6 cells could effectively abolish the formation of vessel-like structures induced by retinoic acid. The percentage of the inhibition was very high, giving a figure comparable to that of atypical vessel-like structures formed in the control embryoid bodies from their parent ES-5 cells. The flat epithelial-like cells and round cells differentiated from embryoid bodies of ES-T6 cells were stained rather strongly for laminin and type IV collagen by immunofluorescent procedure. The above results indicate clearly that TGF-beta 1 is a crucial factor in organizing the differentiated derivatives (endothelial-like cells and their immediate progenitor cells) from ES-T6 cells to form vessel-like structures, and that the role of TGF-beta 1 in vasculogenesis might be performed, in part, through the modulation of the composition and organization of the extracellular matrix. In addition, the enhanced expression of bFGF mRNA in derivatives differentiated from both ES-5 cells treated with rhTGF-beta 1 and ES-T6 cells were detected by Northern blot analysis. Thus, aside from its effects on extracellular matrix, TGF-beta 1 might also modulate the bioactivity of bFGF in relation to the growth of vascular endothelial cells in the present system. 相似文献
830.