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61.
Photoactive membranes coated with TiO2 and Pt/TiO2 nanostructured thin films were produced by one-step deposition of gas phase nanoparticles on glass fiber filters. Pt/TiO2 nanoparticles (0–1.5 wt.% Pt content) were produced by flame spray pyrolysis, starting from liquid solutions of the Ti and Pt precursors, and then expanded in a supersonic beam to be deposited on the filters. The nanostructured coatings were composed of crystalline nanoparticles (mainly anatase phase), without any need of post-deposition annealing. The so obtained photocatalytic membranes were tested in hydrogen production by photo-steam reforming of ethanol in an expressly set-up diffusive photoreactor. The reaction rate was found to increase with increasing the Pt content in the photoactive material, up to 1.5 wt.% Pt. The use of these membranes allowed a significant increase of the hydrogen production rate compared to that obtained with the same photoactive Pt/TiO2 films deposited on a quartz substrate.  相似文献   
62.
Accumulation of pollutants in the aquatic system has a high impact on the reproductive physiology of crustaceans. The objective of the present study was to assess the possible histopathological effects of combined chlorpyrifos and cypermethrin (nurocombi) exposure on reproductive tissue in male freshwater crab Paratelphusa jacquemontii using light and electron microscopy. The testis of experimental crabs showed disorganization of testicular lobules, increased inters cellular space, necrosis, and cellular damage in both germinal cells and Sertoli cells. The treated vas deferens exhibited epithelial degeneration, misshaped spermatophores, decline in the number of spermatophores, and dehiscence of spermatophore wall. These clinical manifestations expressed in crabs following the exposure of nurocombi significantly reduce the testicular activity and substantially inhibits the seminal secretions, which ultimately lead to impairment of reproduction.  相似文献   
63.
Electron microscope (EM) was developed in 1931 and since then microscopical examination of both the biological and non-biological samples has been revolutionized. Modifications in electron microscopy techniques, such as scanning EM and transmission EM, have widened their applicability in the various sectors such as understanding of drug toxicity, development of mechanism, criminal site investigation, and characterization of the nano-molecule. The present review summarizes its role in important aspects such as toxicity assessment and disease diagnosis in special reference to SARS-COV2. In the biological system, EM studies have elucidated the impact of toxicants at the ultra-structural level in various tissue in conformity to physiological alterations. Thus, EM can be concluded as an important tool in toxicity assessment and disease prognosis.  相似文献   
64.
In this paper, different arrangements of Kelvin–Voigt elements are implemented in an admittance matrix model to investigate the transient modeling of water distribution systems. The viscoelastic parameters are calibrated by experimental data acquired during a transient in a branched system of three HDPE pipes at the Water Engineering Laboratory of the University of Perugia, Italy. The dependence of the viscoelastic parameters on the branch characteristic time is investigated. Models with a single set of elements for all branches are compared with models with different sets of elements for each branch. When the same number of parameters is used, the former perform better than the latter. No evident correlation is found between the retardation times of the viscoelastic parameters and the branch characteristic times. The use of two measurement sections instead of one does not modify the calibration results significantly.  相似文献   
65.
The Maggiore Valley well field plays a fundamental role in supplying drinking water to a large territory of the Piedmont (north-western Italy). However, an increasing demand for water has led to the overexploitation of the groundwater resources. This situation has caused a progressive drawdown of the piezometric level (locally, up to 0.8 m/year), a spatial reduction in the artesian zone, localised land subsidence and damage to wells. The main purpose of this study was the development of a groundwater flow model of the area for analysing the aquifer response to various pumping strategies. Initially, the groundwater flow simulation (achieved by the application of the MODFLOW code) was calibrated satisfactorily. Then, the groundwater response to four scenarios was simulated to explore the best option to mitigate the problem. In three of the scenarios, a withdrawal reduction of 110 l/s was simulated, whilst considering various relocation options for extraction within the well field. The fourth scenario simulated a withdrawal reduction of 150 l/s; this option also assumed a supplementary water supply from the Monferrato Aqueduct, located north of the study area. All the simulations provided an increase in the piezometric level; in some instances, up to 30 m. Based on these simulations, the most promising management strategy for the Maggiore Valley well field would seem to be the option using a supplementary feed from the Monferrato Aqueduct. In this instance, the predicted piezometric level rise would be up to 25 m; this option also precludes the need for drilling additional wells.  相似文献   
66.
Measures of economic well‐being are often needed for geographically small areas, as economic indicators may be distributed unevenly among the subsets of relatively small regions. We consider small area estimation of average equivalized income. Disposable household income data are usually available only for a sample of households, typically too small to provide reliable estimates for small regions. We consider a small area estimation technique that is robust to outliers, produces results consistent with design weighted estimates obtained for larger areas and yield maps with approximately no shrinkage. The proposed methodology is applied to the Local Labour Systems in Tuscany (Italy).  相似文献   
67.
We investigated the effects of in vivo intraperitoneal treatment with the rat monoclonal antibody (mAb), YN1.7.4 (YN1) against intercellular adhesion molecule-1 (ICAM-1) on the ovalbumin (OA)-inhalation-induced infiltration of leukocytes into the airways of OA-sensitized mice. YN1 (100 to 400 microg) given over a period of 72 h dose-dependently reduced the influx of lymphocytes and eosinophils into the bronchial lumen by > 60% and > or = 70%, respectively, when compared with saline or purified rat IgG-treated controls. Alveolar macrophages (AM) in the bronchoalveolar lavage fluid (BALF) were also decreased by > 50%. Lung tissue inflammation as determined by histopathologic examination was reduced. The number of neutrophils in the blood of OA-sensitized mice 3 days after challenge was significantly increased by treatment with YN1. However, at 24 h and 72 h after OA-challenge, the numbers of eosinophils and mononuclear cells in the bone marrow were reduced by YN1 treatment. Additionally, at 72 h after OA-challenge, the numbers of bone-marrow neutrophils were depressed. BALF levels of interleukin-5 (IL-5) and of IgA were lower for YN1-treated mice than for controls. With increasing doses of YN1, the levels of anti-ICAM-1 mAb in the plasma were proportionally increased. To correlate these results with YN1 treatment, blood and BALF T cells and BALF eosinophils were examined with flow cytometry. Blood T cells from YN1-treated mice were unable to bind phycoerythrin (PE)-labeled anti-ICAM- mAb ex vivo. These results implied that ICAM-1 on these cells was bound (occupied) by YN1 administered in vivo. Dose-related decreases were observed in the percentage and mean channel fluorescence (MCF) values of ICAM-1+ BALF T cells and eosinophils. The percentages of CD11a+ or CD49d+ eosinophils were also suppressed. Our data suggest that ICAM-1 is an important molecule involved in the recruitment of leukocytes into the airways of sensitized mice after pulmonary challenge.  相似文献   
68.
The catalytic activity of the antibody H11 is shown to reside chiefly in its ability to hydrolyze 1-acetoxybutadiene to crotonaldehyde and to promote the cycloaddition of the intermediate enol with N-alkylmaleimides. This conclusion is based upon the demonstration that the enol tautomerizes too rapidly in solution to be a competent intermediate and that under the reaction conditions for H11, no cycloaddition occurs with crotonaldehyde and N-ethylmaleimide. As a first step towards a structural understanding of the chemistry of H11, chemical modification experiments have shown that reactions of acidic amino acids, tyrosine, lysine, and histidine, but not arginine, inhibit the reactions mediated by H11.  相似文献   
69.
70.
The diagnosis of water distribution systems by means of the inverse transient analysis requires efficient and reliable numerical models. In the network admittance matrix method (NAMM) the 1-D waterhammer governing equations are integrated in the frequency domain and organized in a laplacian matrix form. The NAMM is particularly suitable for complex systems because of this structure and can be used for the system diagnosis, including leak sizing and location. In this paper a damaged branched system is considered and the diagnosis is performed by means of the NAMM using experimental data from laboratory transient tests. Two different boundary conditions are used in the implementation of the NAMM and the leak is located and sized with a reasonable approximation. An extended numerical investigation is also presented and allows confirmation of the results for different leak locations. The use of the NAMM for the leak detection and the validation using experimental data on a branched system are the main original contributions of this work. The successful diagnosis indicates promising results for applications in more complex systems.  相似文献   
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