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41.
In current desktop user interfaces, selection is usually accomplished easily with a mouse or a similar two-dimensional locator. In wearable computing, however, controlling two dimensions simultaneously gets significantly harder: a change in one dimension results easily in an undesired change in the other dimension as well when the user is occupied with a parallel task – such as walking. We present a way to overcome this problem by applying one-dimensional selection for graphical user interfaces in head-worn displays. Our new interaction technique allows a wearable computer user to perform object selection tasks easily and accurately. The technique is based on a visible circle on the screen. The user controls the circle, altering its radius with a one-dimensional valuator. The midpoint of the circle is in the middle of the screen. The object currently on the perimeter of the circle is highlighted and can be selected. Our preliminary usability evaluation, applying our custom evaluation method designed especially for walking users, indicates that the proposed technique is usable also when walking. 相似文献
42.
S. Klages M. Schöck C. Sürgers H. v. Löhneysen 《Journal of Low Temperature Physics》2004,137(3-4):509-522
The morphology and electronic transport of ultrathin Au films with thicknesses d = 1 ? 5 monolayers (ML) deposited on Si(111)7 × 7 surfaces is investigated by in situ scanning tunneling microscopy and electrical resistance measurements for temperatures T = 2 ? 300 K. With decreasing film thickness, i.e. decreasing sheet conductance Gs, a transition from a weakly conducting regime described by a logarithmic temperature dependence to an insulating regime occurs. In the insulating regime, the temperature dependence is described by Gs ∝ exp[?(T 0 /T) n] with an exponent n which gradually changes from 0.69 to 1 with decreasing film thickness. In contrast, for the Si(111)6 × 6-Au reconstruction obtained after annealing, an exponent n = 1/2 is found suggesting the formation of a soft Coulomb gap due to electron-electron interaction. PACS numbers: 68.37.-d, 68.55.-a, 73.50.-h, 73.25.+i, 81.15.-z 相似文献
43.
J. Prinz M. Sajatovic M. Konrad A. Kröpfl J. Hartenberger Ch. Steger 《e & i Elektrotechnik und Informationstechnik》2003,120(2):a16-a19
6. Zusammenfassung In diesem Artikel wurde die Data in Voice-Technologie vorgestellt. DiV ist eine Methode, die es erlaubt, kurze Daten-Messages
gemeinsam mit der Sprache im analogen Flugfunkkanal zu übertragen. Man ist bei FREQUENTIS überzeugt, dass man mit dieser Methode
viele Nachteile des vorhandenen analogen Flugfunks beseitigen und dadurch die Flugsicherheit wesentlich erh?hen k?nnte. 相似文献
44.
A. Schüppen A. Gruhle H. Kibbel U. König 《Journal of Materials Science: Materials in Electronics》1995,6(5):298-305
SiGe-HBTs have the potential for outstanding analog and digital or mixed-signal high frequency circuits widely based on standard Si technology. Here we review on MBE grown transistors and circuits. Processes and results of a research-like SiGe HBT and two possible production relevant HBT versions are presented. The high frequency results with fmax and fT up to 120 GHz and a minimum noise figure of 0.9 dB at 10 GHz demonstrate the advantage of using MBE samples with steep and high base doping and high germanium contents. A comparison to the concept of reported low doped, low germanium and triangular profiled SiGe base layers, realized by UHV-CVD, is given. In addition, some circuit demonstrators of SiGe-ICs will be presented. 相似文献
45.
J. G. Zheng Xiaoqing Pan M. Schweizer U. Weimar W. Göpel M. Rühle 《Journal of Materials Science》1996,31(9):2317-2324
Atomic structures of crystallographic shear planes (CSPs) in nanocrystalline thin films of semiconductor SnO2 were investigated by high-resolution electron microscopy. The films were prepared by electron beam evaporation in high vacuum (10–6 torr) and followed by annealing in synthetic air at 700 °C for 1–2 H. CSPs with the displacement vector of [1/2 0 1/2] were observed in the planes parallel to (¯101), (110) and (¯3¯21). Most of the CPSs were found to terminate or interact with each other within SnO2 crystallites. Partial dislocations exist at terminal places of CSPs or along intersecting lines of CSPs. CSP steps were also observed. Structural models of these defects have been proposed. Based on analysis of experimental data, it has been suggested that the Sn/O ratio at CSPs which are not parallel to their displacement vector, at cores of partial dislocations and at CSP steps, is higher than that of the perfect structure, that is, these defects are able to provide extra free electrons with the films. 相似文献
46.
Klaus Fröhlich Öve Gerfried Zeichen 《e & i Elektrotechnik und Informationstechnik》1998,115(4):226-226
Ohne Zusammenfassung 相似文献
47.
P. Bruelemans P. Janssen K. D. Möller 《Journal of Infrared, Millimeter and Terahertz Waves》1996,17(1):51-59
The construction of a Fourier transform spectrometer to study magnetic resonances in solids is described. The spectrometer operates in the Far Infrared (maximum frequency of 500 cm?1) and is based on a wavefront dividing interferometer with circular geometry. To illustrate the performance, a water vapour spectrum is given. 相似文献
48.
49.
S. Brabetz R. Weidl F. Klemm L. Dörrer F. Schmidl P. Seidel 《Journal of Low Temperature Physics》1997,106(3-4):527-532
We investigated different types of high-Tc DC-SQUID gradiometers with the aim to develop an one-channel heart monitoring system for non-invasive measurements in unshielded
environment. This system could be used to obtain information about the patients condition in serial examinations and in emergency
cases fast and stable. Step-edge and bicrystal Josephson junctions were used to prepare planar galvanically coupled thin film
gradiometers and magnetometers. These sensors were used to carry out measurements in well-shielded and non-shielded environment
and we compared the different noise properties and field gradient resolutions. With different types and sizes of high-Tc DC-SQUID sensors magnetocardiograms were measured in a magnetically shielded room. The influence of antenna configurations,
SQUID parameters, and cooling conditions on the measurement of magnetocardiograms will be discussed. We investigated possibilities
to suppress the earth magnetic field (with pairs of Helmholtz coils) and for noise field compensation in unshielded environment. 相似文献
50.
M. Sanganeria D. T. Grider M. C. öztürk J. J. Wortman 《Journal of Electronic Materials》1992,21(1):61-64
In-situ doped polycrystalline SixGe1-x
(x = 0.7) alloys were deposited by rapid thermal chemical vapor deposition (RTCVD) using the reactive gases SiH2Cl2, GeH4 and B2H6 in a H2 carrier gas. The depositions were performed at a total pressure of 4.0 Torr and at temperatures 600° C, 650° C and 700° C
and different B2H6 flow rates. The conditions were chosen to achieve high doping levels in the deposited films. Our results indicate negligible
effect of B2H6 flow on the deposition rate. The depositions follow an Arrhenius type behavior with an activation energy of 25 kcal/mole.
Boron incorporation in the films was found to follow a simple kinetic model with higher boron levels at lower deposition rates
and higher B2H6 flow rates. As-deposited resistivities as low as 2 mΩ-cm were obtained. Rapid thermal annealing (RTA) in the temperature
range 800-1000° C was found to reduce the resistivity only marginally due to the high levels of boron activation achieved
during the deposition process. The results indicate that polycrystalline SixGe1-x films can be deposited by RTCVD with resistivities comparable to those reported for in-situ doped polysilicon. 相似文献