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161.
Most of the middlewares currently available focus on one type of device (e.g., TinyOS sensors) and/or are designed with one requirement in mind (e.g., data management). This is an important limitation since most of the AmI applications work with several devices (such as sensors, smartphones or PDAs) and use a high diversity of low-level services. Ideally, the middleware should provide a single interface for accessing all those services able to work in heterogeneous devices. To address this issue, we propose a family of configurable middleware (FamiWare) with a really flexible architecture, instead of building a single version of a middleware with a rigid structure. In this work, we present the architecture of our middleware that can be configured, following a Software Product Line approach, in order to be instantiated in a particular device fulfilling specific application requirements. Furthermore, we evaluate that the decisions taken at architecture and implementation are the adequate ones for this kind of constrained devices. 相似文献
162.
Drava G Capelli R Minganti V De Pellegrini R Orsi Relini L Ivaldi M 《The Science of the total environment》2004,321(1-3):87-92
Concentrations of total and organic mercury, cadmium, lead, copper, iron, manganese and zinc were determined in the muscular tissue of 135 specimens of Aristeus antennatus (Risso, 1816) collected during a 3-year period in the Ligurian sea (NW Mediterranean). The aim of the present work was to study the relationships between the concentrations of these trace elements and the main biological parameters characterising the organisms, i.e. sex and size with special attention to the sexual maturity of the female specimens. Mercury is the only element showing a significant correlation with the size of the specimens, and for this reason it could give some indications about the age of the shrimps. However, comparison between females collected at four different reproductive phases shows that reproductive individuals are characterised by higher levels of mercury with respect to non-reproductive individuals of the same size. 相似文献
163.
Petru Pascuta Lidia Pop Simona Rada Maria Bosca Eugen Culea 《Journal of Materials Science: Materials in Electronics》2008,19(5):424-428
Glasses of the xEu2O3 · (100 − x)[4Bi2O3 · B2O3] system, with 0 ≤ x ≤ 40 mol% were studied by FT-IR spectroscopy and density measurements. FT-IR spectroscopy and density data suggest that the
europium ions play the network modifier role in the studied glasses. These data show that the glass structure consists on
the BiO3, BiO6, BO3 and BO4 units, and the conversion among these units mainly depends on the Eu2O3 content. 相似文献
164.
Armelao L Barreca D Gasparotto A Pierangelo E Tondello E Polizzi S 《Journal of nanoscience and nanotechnology》2005,5(2):259-265
Radio frequency sputtering of gold on amorphous silica substrates was used for the preparation of Au nanoparticles on SiO2. Deposition experiments were carried out in Ar plasmas under mild conditions (RF power = 5/10 W, total pressure = 0.38 mbar, substrate temperature < or = 210 degrees C), focusing in particular on the effect of sputtering time (5/30 min) and substrate temperature on gold nucleation and coalescence, with the aim of obtaining SiO2-supported Au nanoparticles characterized by precise structural and morphological features. To this aim, several analytical techniques were employed for a thorough characterization of the systems properties, including glancing incidence X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, atomic force microscopy, and UV-Vis absorption spectroscopy. In particular, the evolution of optical spectra, i.e., of the surface plasmon resonance peak, was used as a probe for the structural features and was related to the results obtained by other characterization techniques. Gold nanoclusters (phi approximately 4/10 nm) dispersed uniformly on silica matrices were obtained under soft conditions, with morphology ranging from island to cluster like. The obtained results make possible a careful modulation of substrate coverage and gold nanoparticle size. 相似文献
165.
Expression of HXT1, a gene encoding a Saccharomyces cerevisiae low-affinity glucose transporter, is regulated by glucose availability, being activated in the presence of glucose and inhibited when the levels of the sugar are scarce. In this study we show that 14-3-3 proteins are involved in the regulation of the expression of HXT1 by glucose. We also demonstrate that 14-3-3 proteins, in complex with Reg1, a regulatory subunit of Glc7 protein phosphatase, interact physically with Grr1 (a component of the SCF-Grr1 ubiquitination complex), a key player in the process of HXT1 induction by glucose. In addition, we show that the TOR kinase pathway participates actively in the induction of HXT1 expression by glucose. Inhibition of the TOR kinase pathway by rapamycin treatment abolishes HXT1 glucose induction. A possible involvement of PP2A protein phosphatase complex, through the Cdc55 B-subunit, in the glucose induction of HXT1 is also discussed. 相似文献
166.
Silvana?Martini Constantin?Bertoli Maria?Lidia?Herrera Ian?Neeson Alejandro?MarangoniEmail author 《Journal of the American Oil Chemists' Society》2005,82(5):319-328
Ultrasonic technology can be used to monitor the crystallization of fats and determine solid fat content (SFC) online. Ultrasonic
waves are attenuated as crystals form and grow, and this attenuation occurs first at higher frequencies. The attenuation of
the ultrasonic signal does not depend on the induction times of crystallization of the systems, or on their thermal behavior;
but it does depend on SFC and on microstructure, particularly on the crystal size. At low SFC values (≈5%), bigger crystals
generate more attenuation. At intermediate SFC values (≈10%), crystal size does not affect signal attenuation and SFC is the
key factor responsible for signal attenuation. At high SFC values (up to 20%), crystal size again seems to be the factor that
controls attenuation. 相似文献
167.
Release rates of pheromones from commercial dispensers for mating disruption inLobesia botrana andCydia pomonella have been measured by sampling an air stream with C-18 bonded silica (Sep-Pak cartridges) followed by extraction and gas chromatographic analysis. The flow chamber is made from inexpensive materials that can be replaced when contaminated. The results correspond with those obtained by gravimetry; the method supplies additional information on the composition of the airborne material. 相似文献
168.
Lidia?SzpyrkowiczEmail author Santosh?N.?Kaul Rao?N.?Neti 《Journal of Applied Electrochemistry》2005,35(4):381-390
The paper is aimed at defining the best option of a combination of electrochemical and biological processes for tannery wastewater treatment. Kinetic data for the electrochemical process are derived from an extensive experimental study, while those relating to biological processes are taken from the authors previously published studies or from the literature. Four different options based on a combination of electrochemical oxidation and biological treatment are defined and compared with the traditional tannery wastewater treatment with respect to the total required volume, energy need and the quantity of generated sludge. 相似文献
169.
Francisco Gómez-Jakobsen Dolores Cortés Teodoro Ramírez Soluna Salles Lidia Yebra 《International journal of remote sensing》2016,37(6):1431-1444
The utility of three different algorithms for retrieving surface chlorophyll-a values from satellite images of MODIS-Aqua is tested in the northern Alboran Sea. The available global algorithm to calculate chlorophyll-a from reflectance of MODIS-Aqua (OC3M) overestimates the surface chlorophyll-a in the study area. Another regional algorithm specifically developed for the Mediterranean Sea (MedOC3) improves the estimates although the best outcome is obtained with OC5, which was developed for Atlantic coastal waters. The three tested algorithms perform worse at in situ chlorophyll-a concentrations higher than 1 mg m?3 and exhibit uncertainty levels higher than 35% for this range of concentrations. A new algorithm (ALBOC3) is proposed which produces a good estimation of the in situ chlorophyll-a for the whole range of concentrations normally registered in the study area (0.1–3.5 mg m?3). We hypothesize that the particular bio-optical features of the northern Alboran Sea phytoplankton explain the poor functioning of the published algorithms that have been tested in this work. 相似文献
170.
In the paper, we consider conjugate problems which constitute a new class of mutually related time-dependent scheduling problems.
Any element from this class is a composite problem, being a pair of two time-dependent scheduling problems connected by a
conjugacy formula. We prove basic properties of conjugate problems and show the relations that hold between such problems.
We also propose an approach to the construction of greedy heuristics for the conjugate problems. We illustrate applications
of the results by examples. 相似文献