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101.
Massimo F. Bertino Bernd Smarsly Antonio Stocco Arne Stark 《Advanced functional materials》2009,19(8):1235-1240
A technique is presented that allows for altering of the physical characteristics of films of TiO2 nanoparticles by exposure to visible light. In this technique, dye‐sensitized oxide nanoparticles are deposited on a substrate by dip‐coating. Photodissociation of the organic ligand layer leads to cross‐linking of the nanoparticles. Consequently, irradiated films have a decreased porosity, an increased index of refraction and an increased hydrophobicity. Films irradiated with green light are compared to films irradiated with UV light. Within experimental error, visible‐ and UV‐illumination induces the same changes in the films. The mechanism of surfactant elimination in dye‐sensitized oxide particles is discussed, patterning is demonstrated, and prospective applications of the technique are considered. 相似文献
102.
J. Antoszewski D. J. Seymour L. Faraone J. R. Meyer C. A. Hoffman 《Journal of Electronic Materials》1995,24(9):1255-1262
A quantitative mobility spectrum analysis (QMSA) of experimental Hall and resistivity data as a function of magnetic field
is presented. This technique enables the conductivity contribution of bulk majority carriers to be separated from that of
other species such as thermally generated minority carriers, electrons, and holes populating n and p doped regions, respectively,
and two-dimensional species at surfaces and interface layers. Starting with a suitable first trial function such as the Beck
and Anderson mobility spectrum analysis (MSA), a variation on the iterative procedure of Dziuba and Gorska is used to obtain
a mobility spectrum which enables the various carrier species present in the sample to be identified. The QMSA algorithm combines
the fully automated execution and visually meaningful output format of MSA with the quantitative accuracy of the conventional
least-squares multi-carrier fitting procedure. Examples of applications to HgCdTe infrared detector materials and InAs/GaSb
quantum wells are discussed. The ultimate goal of this paper is to provide an automated, universal algorithm which may be
used routinely in the analysis and interpretation of magneto-transport data for diverse semiconductor materials and bandgap
engineered structures. 相似文献
103.
Low-power monolithic RF peak detector analysis 总被引:2,自引:0,他引:2
Closed-form expressions are derived for the transfer characteristic of a low-power monolithic RF peak detector. These are compared with computer simulation and experimental measurements 相似文献
104.
Scully CG Lee J Meyer J Gorbach AM Granquist-Fraser D Mendelson Y Chon KH 《IEEE transactions on bio-medical engineering》2012,59(2):303-306
We show that a mobile phone can serve as an accurate monitor for several physiological variables, based on its ability to record and analyze the varying color signals of a fingertip placed in contact with its optical sensor. We confirm the accuracy of measurements of breathing rate, cardiac R-R intervals, and blood oxygen saturation, by comparisons to standard methods for making such measurements (respiration belts, ECGs, and pulse-oximeters, respectively). Measurement of respiratory rate uses a previously reported algorithm developed for use with a pulse-oximeter, based on amplitude and frequency modulation sequences within the light signal. We note that this technology can also be used with recently developed algorithms for detection of atrial fibrillation or blood loss. 相似文献
105.
Heinz E. May T. Born D. Zieger G. Anders S. Zakosarenko V. Meyer H.-G. Schäffel C. 《Journal of Infrared, Millimeter and Terahertz Waves》2015,36(10):879-895
Journal of Infrared, Millimeter, and Terahertz Waves - Passive submillimeter-wave imaging is a concept that has been in the focus of interest as a promising technology for personal security... 相似文献
106.
G. Homm S. Petznick F. Gather T. Henning C. Heiliger B. K. Meyer P. J. Klar 《Journal of Electronic Materials》2011,40(5):801-806
A series of bar-shaped samples consisting of lateral arrangements of alternating ZnO:Al and ZnO stripes was fabricated by radiofrequency (RF)-sputtering and microfabrication techniques on glass substrates. Throughout the series, the number of interfaces between ZnO and ZnO:Al was varied whilst the material fractions of ZnO:Al and ZnO within the bars were not altered. Lateral thermoelectric transport parameters, i.e., Seebeck effect and electrical resistivity, were measured as a function of temperature for all microstructured samples and two reference samples of ZnO:Al and undoped ZnO. The transport direction through the bar was perpendicular to the stripe direction, such that the electrons and phonons have to pass all interfaces. The transport coefficients of the microstructured samples show clear dependence on the number of interfaces between ZnO and ZnO:Al. Thermoelectric measurements, photoluminescence, and Raman measurements indicate that this is due to diffusion of Al donors along the grain boundaries into the undoped ZnO stripes, which takes place during the fabrication process. Modeling of the dependence of the Seebeck coefficient and the resistivity of the series of samples on the basis of a network model accounting for donor diffusion supports these findings. 相似文献
107.
Christian Stephan Bernd 《AEUE-International Journal of Electronics and Communications》2006,60(1):20-24
Security for ad hoc network environments has received a lot of attention as of today. Previous work has mainly been focussing on secure routing, fairness issues, and malicious node detection. However, the issue of introducing and conserving trust relationships has received considerably less attention. In this article, we present a scalable method for the use of public key certificates and their revocation in mobile ad hoc networks (MANETs). With the LKN-ad hoc security framework (LKN-ASF) a certificate management protocol has been introduced, bringing PKI technology to MANETs. In addition a performance analysis of two different revocation approaches for MANETs will be presented. 相似文献
108.
109.
Lukas Spree Fupin Liu Volker Neu Marco Rosenkranz Georgios Velkos Yaofeng Wang Sandra Schiemenz Jan Dreiser Pierluigi Gargiani Manuel Valvidares Chia-Hsiang Chen Bernd Büchner Stanislav M. Avdoshenko Alexey A. Popov 《Advanced functional materials》2021,31(48):2105516
The chemical functionalization of fullerene single molecule magnet Tb2@C80(CH2Ph) enables the facile preparation of robust monolayers on graphene and highly oriented pyrolytic graphite from solution without impairing their magnetic properties. Monolayers of endohedral fullerene functionalized with pyrene exhibit magnetic bistability up to a temperature of 28 K. The use of pyrene terminated linker molecules opens the way to devise integration of spin carrying units encapsulated by fullerene cages on graphitic substrates, be it single-molecule magnets or qubit candidates. 相似文献
110.
Silicon integrated circuit spiral inductors and transformers are analyzed using electromagnetic analysis. With appropriate approximations, the calculations are reduced to electrostatic and magnetostatic calculations. The important effects of substrate loss are included in the analysis. Classic circuit analysis and network analysis techniques are used to derive two-port parameters from the circuits. From two-port measurements, low-order, frequency-independent lumped circuits are used to model the physical behavior over a broad-frequency range. The analysis is applied to traditional square and polygon inductors and transformer structures as well as to multilayer metal structures and coupled inductors. A custom computer-aided-design tool called ASITIC is described, which is used for the analysis, design, and optimization of these structures. Measurements taken over a frequency range from 100 MHz to 5 GHz show good agreement with theory 相似文献