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141.
This article refers to a Molten Carbonate Fuel Cell (MCFC) system coupled to a plant with a microgas turbine and a heat recovery system for obtaining a small sized hybrid system in co‐generative arrangement. MCFC are devices capable of concentrating carbon dioxide (CO2) produced in anode exhaust gases. If they are handled conveniently, it is possible to separate and store the surplus CO2 produced by the plant instead of emitting it into the atmosphere. From the simulation model of the MCFC system, previously developed by the authors, a zero‐dimensional and stationary simulation model for the whole hybrid system was formulated and implemented in the same language. By the simulation model of the MCFC system it has been possible to make a parametric analysis of the hybrid plant to find some optimal operating conditions of the fuel cell(s) that maximise the performance of the entire hybrid plant. In addition, the separation of the CO2 surplus produced by the hybrid plant was simulated by the model and then the emissions of carbon monoxide (CO) and nitrogen oxides (NOx) from the same plant were evaluated. 相似文献
142.
Luciano Favretto Luciana Gabrielli Favretto Lorenzo Felician 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1987,184(2):101-109
Summary Principal component analysis has been applied to analyze the correlation matrix obtained from a 8 × 43 data matrix. The 8 trace metals are Mn, Co, Ni, Cu, Zn, Cd, Hg, Ph, which are contained in the soft part of mussels (Mytilus galloprovincialis Lamarck). Mussels were sampled from two sites in the Gulf of Trieste. In both samples, 76–78% of the total variance is explained by the four principal components. The orthogonally rotated factor matrix indicates that Co and Ni are bonded to the first principal component and Cd and Pb to the first (site 2) or second principal component (site 1). The origin of trace metals in the soft part of mussels from the Gulf of Trieste is discussed.
L. Felician is the author of the statistical analysis for site 1 as a part of his thesis in Commodity Science, Faculty of Economics, University of Trieste- L. Gabrielli Favretto is the author of the statistical analysis of the data for site 2. All authors contributed to the rest of the paper 相似文献
Analyse der Hauptkomponenten zur Identifizierung der Verunreinigungsursachen von Muscheln über die Spurenmetalle
Zusammenfassung Die Analyse der Hauptkomponenten wurde auf die Korrelationsmatrix, die aus der 8 × 43-Datenmatrix hervorgeht, angewandt. Diese 8 Spurenmetalle sind Mn, Co, Ni, Cu, Zn, Cd, Hg, Pb, die im Fleisch der Miesmuscheln (Mytilus galloprovincialis Lamarck) gefunden worden sind. Die Miesmuscheln stammen aus zwei Gegenden des Golfes von Triest. Vier Hauptkomponenten erklären 76–78 % der totalen Varianz der beiden Stichproben. Die orthogonale-rotierte Faktorenmatrix zeigt, daß Co und Ni an die erste Hauptkomponente und Cd und Pb an die erste (Lage 2) oder an die zweite Hauptkomponente (Lage 1) gebunden sind. Die Herkunft der Spurenmetalle im Muschelfleisch aus dem Golf von Triest wird diskutiert.
L. Felician is the author of the statistical analysis for site 1 as a part of his thesis in Commodity Science, Faculty of Economics, University of Trieste- L. Gabrielli Favretto is the author of the statistical analysis of the data for site 2. All authors contributed to the rest of the paper 相似文献
143.
Eva Hierro Juan A. Ordóñez José M. Bruna Carmen Pin Manuela Fernández Lorenzo de la Hoz 《European Food Research and Technology》2005,220(5-6):494-501
The effect of the inoculation of dry fermented sausage surface with an atoxigenic, proteolytic and lipolytic strain of Mucor racemosus, Penicillium aurantiogriseum and Penicillium camemberti on the volatile composition was studied. The analysis of the headspace volatile compounds using gas chromatography/mass spectrometry enabled the identification of 55 volatiles. The study showed that every mould species produced a different volatile profile which was also different from that of the control sausages. Compounds derived from amino acid catabolism, i.e. branched aldehydes and the corresponding alcohols, were produced in higher amounts in sausages inoculated with Penicillium spp. On the other hand, volatiles coming from the microbial esterification were related to sausages inoculated with M. racemosus. The development of the fungal mycelia on the sausage surface protected lipids from oxidation, thus giving rise to fewer lipid oxidation products in the inoculated sausages. 相似文献
144.
Lorenzo Scalise Daniele Rinaldi Fabrizio DavìNicola Paone 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,654(1):122-126
Scintillating crystals are employed in high energy physics, in medical imaging, diagnostic and security. Two mechanical properties of lutetium-yttrium oxyorthosilicate cerium-doped Lu2(1−x)Y2xSiO5:Ce with x=0.1 (LYSO) crystals have been measured: the ultimate tensile stress (σUTS) and the Young elastic modulus (E). Measurements are made by means of a 4-points loading device and the experimental results account for an elastic-brittle stress-strain relation, which depends heavily on the specimen preparation and the material defects. σUTS along the [0 1 0] tensile direction ranges within 68.14 and 115.61 MPa, which, in the lowest case, is more than twice with respect to those measured for PbWO4 (PWO), exhibiting a marked difference between the annealed and the not-annealed samples. The mean elastic modulus (E), along the same direction, is E=1.80×1011 (±2.15×1010) N/m2, with lower dispersion respect to UTS data. This type of analysis and study can be included into quality control procedures of crystals, based on samples taken out of production; such procedures can be established for industrial processing of crystals aimed to the high energy physics (calorimeters) and medical imaging (PET, etc.) applications. 相似文献
145.
Lorenzo Dozio 《Thin》2011
A comprehensive study on the use of a set of trigonometric functions, originally proposed by Beslin and Nicolas [Journal of Sound and Vibration 1997;202:633–55], as admissible solutions in the Ritz method for general vibration analysis of rectangular orthotropic Kirchhoff plates is presented. The approach is denoted here as Trigonometric Ritz method (TRM). Since its introduction, application of TRM was limited to a very few plate problems. The aim of this work is to extend the potential of the method on predicting natural flexural frequencies of plates with various complicating factors, including in-plane loads, elastically restrained edges, rigid/elastic concentrated masses, intermediate line and point supports or their combinations. Computational efficiency, stability, convergence and accuracy of the method are discussed and supported by extensive analysis. TRM-based solutions are compared with many reference cases available in the literature obtained with other methods or Ritz functions. Numerical results indicate that TRM exhibits good to excellent accuracy for all cases considered. New solutions are also presented for future comparison purpose. 相似文献
146.
Maura J. Sheehan Lorenzo Cena Patrick T. O'Shaughnessy Robert A. Gussman 《Aerosol science and technology》2013,47(11):1091-1098
A cyclone was used to modify the droplet output with a three-jet Collison nebulizer. The cyclone-nebulizer system was tested by producing ammonium fluorescein particles from a liquid suspension. The particle size distribution produced with the cyclone was smaller and narrower than that produced without the cyclone. Thus, the cyclone effectively removed the large droplets produced by the nebulizer. The nebulizer-cyclone system reduced the GSD of the output aerosol from 1.7 to 1.4. At the input pressures greater than 138 kPa, the concentration of 10–60 nm particles was greater with the cyclone than without the cyclone. These results are consistent with the shattering of large droplets within the cyclone and re-entrainment of these small secondary droplets. Optimization of the system using cyclone modeling to enhance the sharpness of cut, operational improvements, and decreased venting could maximize the output of tailored distributions of nanoparticles for various applications. 相似文献
147.
Bed and fly ashes originating from industrial-scale fluidized bed combustors (FBCs) were steam hydrated to produce sorbents suitable for further in situ desulphurization. Samples of the hydrated ash were characterized by X-ray diffraction analysis, scanning electron microscopy and porosimetry. Bed ashes were hydrated in a pressure bomb for 30 and 60 min at 200 °C and 250 °C. Fly ash was hydrated in an electrically heated tubular reactor for 10 and 60 min at 200 °C and 300 °C. The results were interpreted by considering the hydration process and the related development of accessible porosity suitable for resulphation. The performance of the reactivated bed ash as sulphur sorbent improved with a decrease of both the hydration temperature and time. For reactivated fly ash, more favourable porosimetric features were observed at longer treatment times and lower hydration temperatures. Finally, it was shown that an ashing treatment (at 850 °C for 20 min) promoted a speeding up of the hydration process and an increase in the accessible porosity. 相似文献
148.
149.
The authors describe a low-power, battery-free tag for use in pervasive sensing applications such as wearable patient-monitoring systems and body sensor networks. The tag consists of a custom integrated circuit, an antenna for RF energy harvesting, and several sensors for monitoring important physiological parameters and generating alarms when necessary. They also describe experimental results with phonocardiogram and photoplethysmogram signals and demonstrate tag localization within 0.6 m by using an audio localization scheme. 相似文献
150.
José Molina-Ruiz María José Martínez-Sánchez Carmen Pérez-Sirvent Mari Luz Tudela-Serrano Mari Luz García Lorenzo 《Renewable Energy》2011,36(3):1125-1132
Wind energy represents one of the most important renewable resources. Wind energy is a clean, renewable and its benefits are considered greater than the disadvantages. However, even though wind farms represent environmentally friendly projects, they frequently generate public resistance.One of the main disadvantages of wind farm construction projects is their poor aesthetic integration into the landscape. On the other hand, landscape impact of wind farms could be minimised if the visual impact is previously evaluated.As regards with the European legislation, the procedure of environmental impact assessment study is necessary before a wind farm project could be established. In contrast, there is not an objective methodology to assess the visual impact of wind farms.The aim of this work was to develop a methodology to predict and evaluate, before its construction, the visual impact of wind farms, taking into account the visualscape from different observation points.Proposed methodology could help to determine and evaluate the best location for new wind farm projects. Moreover, this method could be used as a consulting tool for public organization and private institutions, being quick, concise and clear. 相似文献