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991.
José M. del Álamo Antonio M. Fernández Rubén Trapero Juan C. Yelmo Miguel A. Monjas 《Mobile Networks and Applications》2011,16(4):446-459
The subscribers’ personal information and services that mobile operators are able to provide to Web developers offer new and
exciting possibilities in numerous domains. However, bringing mobile information services to the Web to enable a new generation
of mobile Web services presents several research challenges on identity and privacy management. In this paper, we describe
a framework for identity management in mobile services that empowers users to govern the use and release of their personal
information. Our framework is based on a brokering approach that intermediates between the mobile operator’s information services
and the Web service providers. By leveraging on Web services, identity management infrastructure and privacy enhancing technologies,
our framework provides an effective, privacy-considerate delivery of services over the mobile Web environment. This paper
describes the design principles and architecture of the framework as well as the feasibility, applicability and user-experience
evaluation we have carried out. 相似文献
992.
Mario Caironi Matt Bird Daniele Fazzi Zhihua Chen Riccardo Di Pietro Christopher Newman Antonio Facchetti Henning Sirringhaus 《Advanced functional materials》2011,21(17):3371-3381
Charge transport is investigated in high‐mobility n‐channel organic field‐effect transistors (OFETs) based on poly{[N,N′‐bis(2‐octyldodecyl)‐naphthalene‐1,4,5,8‐bis(dicarboximide)‐2,6‐diyl]‐alt‐5,5′‐(2,2′‐bithiophene)} (P(NDI2OD‐T2), Polyera ActivInk? N2200) with variable‐temperature electrical measurements and charge‐modulation spectroscopy. Results indicate an unusually uniform energetic landscape of sites for charge‐carrier transport along the channel of the transistor as the main reason for the observed high‐electron mobility. Consistent with a lateral field‐independent transport at temperatures down to 10 K, the reorganization energy is proposed to play an important role in determining the activation energy for the mobility. Quantum chemical calculations, which show an efficient electronic coupling between adjacent units and a reorganization energy of a few hundred meV, are consistent with these findings. 相似文献
993.
Simone Fabiano He Wang Claudia Piliego Cherno Jaye Daniel A. Fischer Zhihua Chen Bruno Pignataro Antonio Facchetti Yueh‐Lin Loo Maria Antonietta Loi 《Advanced functional materials》2011,21(23):4479-4486
N,N′‐1H,1H‐perfluorobutyl dicyanoperylenecarboxydiimide (PDIF‐CN2), a soluble and air stable n‐type molecule, undergoes significant reorganization upon thermal annealing after solution deposition on several substrates with different surface energies. Interestingly, this system exhibits an exceptional edge‐on orientation regardless of the substrate chemistry. This preferential orientation is rationalized in terms of strong intermolecular interactions between the PDIF‐CN2 molecules. The presence of a pronounced π–π stacking is confirmed by combining near‐edge X‐ray absorption fine structure spectroscopy (NEXAFS), dynamic scanning force microscopy (SFM) and surface energy measurements. The remarkable charge carrier mobility measured in field‐effect transistors, using both bottom‐ and top‐contact (bottom‐gate) configurations, underlines the importance of strong intermolecular interactions for the realization of high performing devices. 相似文献
994.
Montella A Aria M D'Ambrosio A Galante F Mauriello F Pernetti M 《Accident; analysis and prevention》2011,43(6):2072-2084
Aim of the study was to investigate, by means of a driving simulator experiment, drivers’ behaviour in terms of speed, deceleration, and lateral position on major approaches of rural intersections in relation to different perceptual cues.In the experiment, ten different design conditions with and without speed-reducing treatments along the approach to the intersection were tested. Twenty-three drivers drove a test route two times and data from the second drive were used for comparison. The order of the ten design conditions was counterbalanced for all the drivers to minimize the presentation order effect. Three different data analysis techniques were used: (a) cluster analysis of speed and lateral position data, (b) statistical tests of speed and lateral position data, and (c) categorical analysis of deceleration behaviour patterns.The most effective treatments were the dragon teeth markings (based on the principle of optical road narrowing), the colored intersection area (based on the principle of intersection highlighting), and the raised median island (based on the principle of physical road narrowing). These measures, in comparison to the base intersection, produced: (1) a significant speed reduction starting from 250 m before the intersection in the range between 13 and 23 km/h, (2) a significant change in the deceleration behaviour with a reduction in the proportion of drivers which did not decelerate, and (3) a shift away from the intersection of the deceleration beginning. Given the significant effects on drivers’ behaviour, the dragon teeth markings, the colored intersection area, and the raised median island are strongly recommended for real world implementation. 相似文献
995.
996.
Bonilla D Mallén M de la Rica R Fernández-Sánchez C Baldi A 《Analytical chemistry》2011,83(5):1726-1731
A new approach for the electrical readout of microarrays prepared on regular glass slides, using an array of impedimetric transducers (interdigitated electrodes, IDEs) is presented in this work. Impedance detection relies on the use of a urease-labeled immunoassay scheme. Urease is able to produce an increase in conductivity by hydrolysis of the urea substrate, which is measured with the IDEs and directly related to the amount of target analyte. Unlike previous electrical microarrays, the assay does not take place on top of the transducers but on a regular glass slide, which may enable the development of compact multiplexed analytical systems with lower cost per assay. A droplet of solution with the enzymatic substrate is deposited on each transducer of the array, and the microarray is positioned at a short distance (300 μm) so that each droplet wets one transducer and one spot of the microarray. This procedure allows reusing the transducer array for readout of a virtually unlimited number of microarrays. A microarray based on an immunoassay for the detection of a mouse generic protein in a concentration range from 0.03 to 30 μg mL(-1) was carried out to assess the performance of the electrical readout approach. A sigmoid response with a limit of detection of 0.1 μg mL(-1) and a dynamic range of 1 order of magnitude was obtained. A comparative study was also carried out with two well established analytical procedures. First, the urease-based immunoassay was tested in a 96 well microtiter plate using phenol red pH indicator and absorbance detection. Second, the microarray was carried out using the same target protein concentration range but applying a Cy3 label and fluorescence detection. Both assays allowed for the validation of the performance of the presented electrical readout system. 相似文献
997.
Isarain-Chávez E Rodríguez RM Cabot PL Centellas F Arias C Garrido JA Brillas E 《Water research》2011,45(14):4119-4130
The degradation of the beta-blockers atenolol, metoprolol tartrate and propranolol hydrochloride was studied by electro-Fenton (EF) and solar photoelectro-Fenton (SPEF). Solutions of 10 L of 100 mg L−1 of total organic carbon of each drug in 0.1 M Na2SO4 with 0.5 mM Fe2+ of pH 3.0 were treated in a recirculation flow plant with an electrochemical reactor coupled with a solar compound parabolic collector. Single Pt/carbon felt (CF) and boron-doped diamond (BDD)/air-diffusion electrode (ADE) cells and combined Pt/ADE-Pt/CF and BDD/ADE-Pt/CF cells were used. SPEF treatments were more potent with the latter cell, yielding 95-97% mineralization with 100% of maximum current efficiency and energy consumptions of about 0.250 kWh g TOC−1. However, the Pt/ADE-Pt/CF cell gave much lower energy consumptions of about 0.080 kWh g TOC−1 with slightly lower mineralization of 88-93%, then being more useful for its possible application at industrial level. The EF method led to a poorer mineralization and was more potent using the combined cells by the additional production of hydroxyl radicals (•OH) from Fenton’s reaction from the fast Fe2+ regeneration at the CF cathode. Organics were also more rapidly destroyed at BDD than at Pt anode. The decay kinetics of beta-blockers always followed a pseudo first-order reaction, although in SPEF, it was accelerated by the additional production of •OH from the action of UV light of solar irradiation. Aromatic intermediates were also destroyed by hydroxyl radicals. Ultimate carboxylic acids like oxalic and oxamic remained in the treated solutions by EF, but their Fe(III) complexes were photolyzed by solar irradiation in SPEF, thus explaining its higher oxidation power. NO3− was the predominant inorganic ion lost in EF, whereas the SPEF process favored the production of NH4+ ion and volatile N-derivatives. 相似文献
998.
This paper describes a methodology for the analysis and design of Reinforced Concrete (RC) tall bridge piers with hollow rectangular sections, which are typically used in deep valley bridge viaducts. Piers are usually considered tall when the shaft has a height of 50 m or more. Three different types of rectangular hollow tall piers have been studied for road piers of 90.00 m in height: RTRA90, RLON90 and RLT90. RTRA90 has the two side walls inclined, RLON90 has the two frontal walls inclined and RLT90 has all four walls inclined. The procedure used in the present study to solve the combinatorial problem is a variant of the ant colony optimization. RTRA90 leads to the most economical pier, both in column and foundation cost, since it is the most efficient set up for horizontal loads. Regarding the cost of the vertical column only, i.e. excluding the foundation, the cost of RTRA90 and RLON90 are similar, but the cost of the column RLT90 is higher due to its larger unit cost of interior formwork. 相似文献
999.
José Manuel Delgado‐López Ruggero Frison Antonio Cervellino Jaime Gómez‐Morales Antonietta Guagliardi Norberto Masciocchi 《Advanced functional materials》2014,24(8):1090-1099
Bio‐inspired apatite nanoparticles precipitated in the presence of citrate ions at increasing maturation times are characterized in terms of structure, size, morphology, and composition through advanced X‐ray total scattering techniques. The origin of the platy crystal morphology, breaking the hexagonal symmetry, and the role of citrate ions is explored. By cross‐coupling the size and shape information of crystal domains with those obtained by atomic force microscopy on multidomain nanoparticles, a plausible mechanism underlying the amorphous‐to‐crystal transformation is reconstructed. In the present study, citrate plays the distinct roles of inducing the platy morphology of the amorphous precursor and controlling the thickness of the Ca‐deficient apatite nanocrystals. These findings can open new scenarios also in bone mineralization, where citrate might have a broader role to play than has been thought to date. 相似文献