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41.
Predd Joel Pfleeger Shari Lawrence Hunker Jeffrey Bulford Carla 《Security & Privacy, IEEE》2008,6(4):66-70
This column goes beyond previous insider analyses to identify a framework for a taxonomy of insider threats including both malicious and inadvertent actions by insiders that put organizations or their resources at some risk. The framework includes factors reflecting the organization, the individual, the information technology system, and the environment. 相似文献
42.
Nalavany Blace A.; Ryan Scott D.; Gomory Tomi; Lacasse Jeffrey R. 《Canadian Metallurgical Quarterly》2005,14(1):27
In this pilot study, concept mapping, a methodological approach combining qualitative and quantitative analytic strategies, was used to identify the therapist qualities, competencies, and skills necessary for effective play therapy outcomes as perceived by a sub-sample of 28 experienced play therapists who are members of the Association for Play Therapy (APT). The clusters associated with the therapeutic relationship and facilitative skills (e.g., empathy, warmth, and genuineness) were rated as the most essential skills to possess and also as the most difficult to develop. In contrast, the clusters associated with play therapy interventions and theories were rated as the least important skills to possess but as the easiest to acquire. The findings are discussed, with implications for therapeutic practice, research, and policy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
R. A. Pethrick D. Hayward K. Jeffrey S. Affrossman P. Wilford 《Journal of Materials Science》1996,31(10):2623-2629
Aluminium oxide exists in several forms which on addition of water give a complex range of oxide-hydroxide; boehmite, bayerite and gibbsite. High frequency dielectric measurements {300 kHz-3 GHz} are reported on the hydrated and dehydration of certain of these oxide-hydroxides. The amplitude of the observed dielectric relaxation correlates approximately with the water content, however anomalies can be observed during dehydration due to the retention of water in an immobilized form within the oxide matrix which highlights complexities in their structure and properties. These data indicate the potential of the dielectric method for quantification of the degree of hydration of an oxide in adhesive bonded structures. Two silane coupled alumina samples were studied to simulate the interface generated in the pre-treatment of real adhesive bonded structures. 相似文献
44.
The most influential study of the person–environment (P–E) fit approach to stress was conducted by J. R. French et al (1982). Unfortunately, this study operationalized fit using various transformations of difference scores, thereby introducing numerous substantive and methodological problems. In the present study, the authors reanalyze data from French et al, using a procedure described by J. R. Edwards (in press) that avoids problems with difference scores and captures the underlying 3-dimensional relationship between environment, person, and strain. Results resolve ambiguities in the French et al findings and identify relationships between environment, person, and strain that, although consistent with P–E fit theory, cannot be adequately represented by fit measures such as those used by French et al. Implications for P–E fit research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Mammalian mothers provide water to their young via milk. Rodent mothers reclaim much of this water by licking the anogenital areas of their pups, stimulating reflexive urination and consuming the pups' urine. Male rodents do not provide milk (hence water) to the young, but in some species male parents may nevertheless lick their pups. We determined the amount of water transfer from pups to mothers and fathers in the biparental California mouse, Peromyscus californicus, by injecting 5-, 10-, 20-, and 30-day-old pups with tritiated water and measuring the radioactive label in maternal and paternal plasma after 24 hrs of interaction with their litter. On Days 5 and 10, mothers obtained more pup urine than did fathers. Parents consumed equivalent amounts of pup urine on Days 20 and 30. Mothers engaged in more pup anogential licking than did fathers, which accounted for the difference in pup urine consumption. Salt appetite controls, in part, pup anogential licking in lactating rats (Gubernick & Alberts, 1983). Salt appetite was not implicated in the modulation of anogential licking in the California mouse because the mice failed to display a salt appetite. Licking of young and urine consumption are not dependent solely on the bidirectional exchange of water between the dam and her offspring. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
Jeffrey E. Marchese Matteo Cirillo Niels Grøch-Jensen 《Open Systems & Information Dynamics》2007,14(2):189-196
We present evidence for a close analogy between the nonlinear behaviour of a pulsed microwave-driven Josephson junction at
low temperature and the experimentally observed behaviour of Josephson systems operated below the quantum transition temperature
under similar conditions. We specifically address observations of Ramsey-type fringe oscillations, which can be understood
in classical nonlinear dynamics as results of slow transient oscillations in a pulsed microwave environment. Simulations are
conducted to mimic experimental measurements by recording the statistics of microwave-induced escape events from the anharmonic
potential well of a zero-voltage state. Observations consistent with experimentally obtained Ramsey-type oscillations are
found in the classical model.
An erratum to this article can be found at 相似文献
47.
In the design of algorithms for large-scale applications it is essential to consider the problem of minimizing I/O communication.
Geographical information systems (GIS) are good examples of such large-scale applications as they frequently handle huge amounts
of spatial data. In this paper we develop efficient external-memory algorithms for a number of important problems involving
line segments in the plane, including trapezoid decomposition, batched planar point location, triangulation, red--blue line
segment intersection reporting, and general line segment intersection reporting. In GIS systems the first three problems are
useful for rendering and modeling, and the latter two are frequently used for overlaying maps and extracting information from
them. 相似文献
48.
Results of Schlipf (J Comput Syst Sci 51:64?C86, 1995) and Fitting (Theor Comput Sci 278:25?C51, 2001) show that the well-founded semantics of a finite predicate logic program can be quite complex. In this paper, we show that there is a close connection between the construction of the perfect kernel of a $\Pi^0_1$ class via the iteration of the Cantor?CBendixson derivative through the ordinals and the construction of the well-founded semantics for finite predicate logic programs via Van Gelder??s alternating fixpoint construction. This connection allows us to transfer known complexity results for the perfect kernel of $\Pi^0_1$ classes to give new complexity results for various questions about the well-founded semantics ${\mathit{wfs}}(P)$ of a finite predicate logic program P. 相似文献
49.
Mechanical damping and dynamic modulus measurements in alumina and tungsten fibre-reinforced aluminium composites 总被引:2,自引:0,他引:2
Simultaneous measurements of mechanical damping, or internal friction (Q
–1 ), and dynamic Young's modulus (E) were made near 80 kHz and at strain amplitudes () in the range 10–8 to 10–4 on small specimens of continuous or chopped fibre-reinforced metal matrix composites (MMCs): 6061 aluminium reinforced with alumina (Al/Al2O3) and 6061 aluminium reinforced with tungsten (Al/W). Baseline experiments were also done on 99.999% aluminium (pure Al). The strain amplitude dependence of damping and the temperature dependence of dynamic modulus were of particular interest in this study. The temperature (T) dependence of the modulus from room temperature up to 475° C was determined for the Al/Al2O3 and pure Al specimens and a highly linear decrease in modulus with increasing temperature was observed. The rate of modulus loss (dE/dT –80 M Pa° C–1 ) was the same for both materials and the reduction in modulus of the Al/Al2O3 was attributed to the reduction in modulus of the alu minium matrix, not the alumina fibres. The size, type, and amount of fibre reinforcement were found to have a significant effect on the strain amplitude dependence of the damping in both MMCs. Unreinforced aluminium exhibited classical dislocation damping trends with a region of strain amplitude independent damping at low strains (less than 10–5) followed by a non linear, strain amplitude dependent region at higher strains. The addition of alumina fibres (chopped or continuous), while increasing stiffness, resulted in a significant reduction in damping capacity for the MMC relative to that for aluminium and near complete suppression of the amplitude dependent response. The damping levels increased as the volume fraction of fibre, and therefore, the amount of fibre/matrix (FM) interface decreased, indicating that the matrix, not factors such as increased dislocation densities at the FM interface, was the dominant influence on the damping. Analysis of the Al/Al2O3 results by Granato-Lücke (GL) theory indicated that dislocation densities were increased relative to those in aluminium, but the dis locations were well pinned and unable to increase damping levels effectively. Analysis of the Al/W results by GL theory also revealed high dislocation densities, but, unlike the Al/Al2O3 specimens, the Al/W specimens (continuous fibres) exhibited strong amplitude dependent damping (starting near strain levels of 2 × 10–6) with damping levels approximately twice those of pure aluminium. Trends showed increased damping with increased fibre diameter, not with increased FM interface area. There was some evidence that it was the tungsten fibre itself that dominated the damping behaviour in Al/W composites, not the aluminium matrix or the FM interface. 相似文献