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111.
H. Fathollahnejad R. Rajesh J. Liu R. Droopad G. N. Maracas R. W. Carpenter 《Journal of Electronic Materials》1995,24(1):35-38
A low resistance PdGe nonalloyed ohmic contact has been successfully formed to epitaxially lifted-off n-type GaAs films. The
contact is made by lifting off partially metallized n-type GaAs films using the epitaxial lift-off method and bonding them
to metallized Si substrates by natural intermolecular Van Der Waals forces. Low temperature sintering (200°C) of this contact
results in metallurgical bonding and formation of the ohmic contact. We have measured specific contact resistances of 5 ×
10−5 Ω-cm2 which is almost half the value obtained for pure Pd contacts. Germanium forms a degenerately doped heterojunction interfacial
layer to GaAs. Our experimental results show that germanium diffuses to the interface and acts as a dopant layer to n-GaAs
film surface. Therefore, for epitaxially lifted-off n-type GaAs films, PdGe is a low resistance ohmic metal contact to use. 相似文献
112.
The thermal stability of Ti/Pt/Au Schottky contacts on n-GaAs with Ti films 0–60 nm is investigated. The contacts with Ti films as small as 10 nm remain thermally stable with annealing up to 400°C. The changes induced by thermal treatment in the electrical characteristics of the contacts are correlated with the Rutherford backscattering and microscopic analysis of the annealed samples. It shows profuse interdiffusion and interfacial reaction with 300°C anneal for the GaAs/Pt/Au system. It has been found that introducing the Ti film between GaAs and Pt/Au, the interdiffusion of Pt and Au is also prevented. These results are useful for reducing the gate metallisation resistance of metal semiconductor field effect transistors. 相似文献
113.
Reports an error in the original article "A Longitudinal Study of Who Seeks Counseling When" by W. Harry Sharp and Barbara A. Kirk (Journal of Counseling Psychology, 1974[Jan], 21[1], 43-50). The sentence on page 50 should read as follows: "They appeared to be more intellectually oriented, less personally integrated, and altruistically inclined." (The following abstract of this article originally appeared in record 1974-26400-001.) Determined at what time the members of a university freshman class who sought counseling initiated their contacts with counselors. Over the 4-yr period 401 males and 319 females sought counseling. In general, the rate of initiation declined steeply over time, both by years and by quarters within years. An occasional reversal occurred for females. Characteristics of the Ss as related to time of initiating counseling were also studied, utilizing scores on the School and College Ability Test, Omnibus Personality Inventory, and SVIB, administered in freshman orientation. Neither male nor female Ss differed significantly in test results when time of counseling initiation was considered by the 4 academic quarters. By year, quarter by quarter, and by parts of quarters, the Omnibus Personality Inventory yielded significant results on some scales. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
114.
115.
T. N. Oder T. L. Sung M. Barlow J. R. Williams A. C. Ahyi T. Isaacs-Smith 《Journal of Electronic Materials》2009,38(6):772-777
High-temperature processing was used to improve the barrier properties of three sets of n-type 4H-SiC Schottky diodes fabricated with Ni Schottky contacts. We obtained an optimum average barrier height of 1.78 eV
and an ideality factor of 1.09 using current–voltage measurements on diodes annealed in vacuum at 500°C for 24 h. Nonannealed
contacts had an average barrier height of 1.48 eV and an ideality factor of 1.85. The Rutherford backscattering spectra of
the Ni/SiC contacts revealed the formation of a nickel silicide at the interface, accompanied by a substantial reduction in
oxygen following annealing. 相似文献
116.
A Novel Stress Characterization Technique for the Development of Low-Stress Ohmic Contacts to HgCdTe
D. D’Orsogna P. Lamarre E. Bellotti P. E. Barbone F. Smith C. Fulk P. LoVecchio M. B. Reine S. P. Tobin J. Markunas 《Journal of Electronic Materials》2009,38(8):1698-1706
HgCdTe material intended for long-wavelength infrared detection is particularly susceptible to damage from stress. As a result,
an ideal ohmic contact needs to have good adhesion and low specific contact resistance. The contact should act as a diffusion
barrier and induce the least amount of stress in the underlying material. In this paper we present a set of stress measurements
from different ohmic contact materials deposited on short- and long-wavelength HgCdTe films grown by liquid-phase epitaxy
(LPE). Using a new experimental technique we remove the substrate and measure the stress induced on single- and multilayered
HgCdTe cantilevers. To interpret our results, we develop a theoretical model that describes the physics of elastic deformation
in HgCdTe layers. Our model is based on classical thin-plate bending theory and explicitly takes into account the realistic
boundary conditions that are present in the experimental setup by using a variational approach. 相似文献
117.
This paper reports the DC steady-state current-voltage and conductance-voltage characteristics of a Bipolar Field-Effect Transistor(BiFET) under the unipolar(electron) current mode of operation,with bipolar(elec-tron and hole) charge distributions considered.The model BiFET example presented has two MOS-gates on the two surfaces of a thin pure silicon base layer with electron and hole contacts on both edges of the thin base.The hole contacts on both edges of the thin pure base layer are grounded to give zer... 相似文献
118.
This paper reports the physical realization of the Bipolar Field-Effect Transistor (BiFET) and its one-transistor basic building block circuits. Examples are given for the one and two MOS gates on thin and thick, pure and impure base, with electron and hole contacts, and the corresponding theoretical current-voltage characteristics previously computed by us, without generation-recombination-trapping-tunneling of electrons and holes. These ex-amples include the one-MOS-gate on semi-infinite thick impure base transistor (the bulk transistor) and the impure-thin-base Silicon-on-Insulator (SOI) transistor and the two-MOS-gates on thin base transistors (the FinFET and the Thin Film Transistor TFT). Figures are given with the cross-section views containing the electron and hole concen-tration and current density distributions and trajectories and the corresponding DC current-voltage characteristics. 相似文献
119.
对不同状态含氮奥氏体钢板和马氏体钢板进行了抗枪弹与抗杆式模拟弹试验,分析了它们的穿甲机理。含氮奥氏体钢具有优良的抗弹性能,并优于传统马氏体钢的抗弹性能。马氏体钢抗杆式模拟弹防护系数随着强度的提高而提高,呈线性关系,含氮奥氏体钢穿甲防护系数远远高于同一强度级别的马氏体钢。研究表明,含氮奥氏体钢的抗弹性能的提高主要通过冲击硬化,动态强度明显提高,以及通过塑性变形区域增加,使弹丸更多的能量转换成塑性变形能。 相似文献
120.