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101.
Hodgins D. Bertsch A. Post N. Frischholz M. Volckaerts B. Spensley J. Wasikiewicz J.M. Higgins H. von Stetten F. Kenney L. 《Pervasive Computing, IEEE》2008,7(1):14-21
Healthy Aims is a 23- million, four-year project, funded under the EU's information society technology sixth framework program to develop intelligent medical implants and diagnostic systems (www.healthyaims.org). The project has 25 partners from 10 countries, including commercial, clinical, and research groups. This consortium represents a combination of disciplines to design and fabricate new medical devices and components as well as to test them in laboratories and subsequent clinical trials. The project focuses on medical implants for nerve stimulation and diagnostic equipment based on strain-gauge technology. 相似文献
102.
Rudolf Felix 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2008,12(2):129-135
Real world applications of a decision model of relationships between goals based on fuzzy relations are presented. In contrast
to other approaches the relationships between decision goals or criteria for each decision situation are represented and calculated
explicitly. The application fields are decision making for financial services and optimization of production sequences in
car manufacturing. 相似文献
103.
M. Charpentier Ph.D. Student D. Daloz E. Gautier G. Lesoult A. Hazotte M. Grange 《Metallurgical and Materials Transactions A》2003,34(10):2139-2148
One major hindrance to effective implementation of cast gamma TiAl-based intermetallic alloys in aircraft engines lies in
the variability of their mechanical properties resulting from chemical and microstructural heterogeneities. In the present
work, the buildup of microsegregation in a cast Ti-48Al-2Cr-2Nb alloy is investigated through experiments of quenching during
directional solidification (QDS). The solidification process, as well as the partitioning of alloying elements, between the
solid and liquid phases, is investigated. Considering experimental conditions, the α-hcp phase is found to be the primary solidifying phase. A low dendrite tip temperature of 1475 °C was estimated from thermal
recordings. These observations could be explained considering the value of the thermal gradient (around 4 °C/mm). Quantitative
values of partition coefficients are proposed for Al, Cr, and Nb. In addition to Al, Cr is found to segregate in interdendritic
regions, whereas Nb tends to be retained in the Ti-rich inner dendrites. Considering experimental cumulative solute distributions,
the buildup of microsegregation can be satisfactorily represented on the basis of Gulliver-Scheil assumptions. Due to high-temperature
quenching, the QDS experiments are also found to be appropriate to the study of high-temperature phase transformations and
microstructural development of TiAl-based alloys. The results of QDS experiments are discussed with regard to the range of
microstructural and chemical heterogeneities determined within Ti-48Al-2Cr-2Nb investment castings. Finally, regarding solid-state
phase transformations subsequent to solidification, the study attempts to explain the formation of B2 phase particles stabilized
by the ternary additions.
This article is based on a presentation made in the symposium entitled “Fundamentals of Structural Intermetallics,” presented
at the 2002 TMS Annual Meeting, February 17–21, 2002, in Seattle, Washington, under the auspices of the ASM and TMS Joint
Committee on Mechanical Behavior of Materials. 相似文献
104.
105.
ML Israel DA Connolly RE von Heyn JM Rock PW Smith 《Canadian Metallurgical Quarterly》1993,24(4):343-355
Fifty-two case-hardened, severely self-abusive and aggressive autistic and retarded students, living in six different community residences, were trained to exit their residences, without the presence or assistance of staff, when a fire alarm sounded at night. On a pretest, prior to an 11-week period of intensive environmental and behavioral interventions, only 25% of the students exited within 2 1/2 minutes and independent of staff assistance. At posttest, 100% exited successfully, in a mean evacuation time of 60 seconds. The study was conducted at the Behavior Research Institute (BRI). 相似文献
106.
Fifty-six fourth-grade children participated in this study to assess three training procedures for relative effectiveness in acquiring fire emergency skills and attaining knowledge. The first training approach was behavioral, the second used animated graphics, and the third used still graphics. Each of the training groups was compared to a control group that received no treatment. Performance on dependent measures was assessed before and immediately after training. It was hypothesized that the behavioral and animated-graphics conditions would produce the greatest level of skill and knowledge acquisition. Results demonstrated a significantly higher level of fire emergency skill acquisition and knowledge attainment for both the behavioral and animated-graphics groups relative to the still-graphics group and the control group, which had no training. The value of using computer-mediated strategies for fire-safety skills training was demonstrated. 相似文献
107.
108.
109.
Fiber-reinforced ceramic-matrix composites (CMCs) have been shown to exhibit excellent high-temperature properties. There are some published data on the mechanical properties of Nicalon fiber-reinforced composites with various matrices, but much of the work was performed in bending, and there is little information on the failure modes in textile-reinforced CMCs, especially under cyclic-loading conditions. This article is an interim report on research that examines the tensile deformation, fracture, smoothbar fatigue, and fatigue crack-growth behavior of several CMCs. Unidirectional, two-dimensional eight-harness satin weave, and three-dimensional angle-interlock weave Nicalon fiber architectures infiltrated with polymers and then pyrolized were investigated and are compared with similar experiments on Nicalon-reinforced calcium-silicate glass-ceramic-matrix composites. 相似文献
110.
G. Eilers M. von Ortenberg R. Galazka 《Journal of Infrared, Millimeter and Terahertz Waves》1994,15(4):695-722
The electron paramagnetic resonance (EPR) of Mn2+ in Cd1?x Mn x Te was examined at low temperatures and high magnetic fields with the Mn concentration ranging fromx=0.01 tox=0.65. A far infrared laser was used as a radiation source. The structure of the resonance is strongly influenced by electromagnetic propagation effects. By variation of the sample thickness it was clearly shown that the satellite structures besides the main EPR peak, formerly explained as originating from transitions in the Mn2+ pair energy level scheme, are solely due to interference effects. 相似文献