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91.
Capaldi Elizabeth D.; Hunter Martin J.; Privitera Gregory J. 《Canadian Metallurgical Quarterly》2004,118(6):1400
The present research addresses whether rats can express odor aversions to the odor of taste stimuli. In Experiment 1, saccharin or salt were either mixed in distilled water, so the rats could taste and smell them, or presented on disks attached to the tubes' metal spouts so the rats could only smell them. Aversions were established to taste stimuli under both conditions. The results of Experiment 2 indicate that conditioning was to the odor of the tastes when they were presented on disks in Experiment 1, hence both taste and odor aversions were established by means of "taste" stimuli. Taste aversion learning thus may more properly be termed flavor aversion learning, with flavor referring to both taste and odor components. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
Filippo Lanubile 《Empirical Software Engineering》1997,2(2):97-108
Technology evaluation is part of the decision-making process of any software organization. Unlike conventional wisdom, empirical
evaluation strives to avoid biased conclusions by relying on observation and looking for pitfalls in the evaluation process.
In this paper, we provide a summary of the maintenance studies presented in the session ‘Study and assessment of (new) technologies’
of the International Workshop on Empirical Studies of Software Maintenance (WESS '96), and also report on the working group
discussion which focused on common problems and open issues in the field of technology evaluation. These empirical studies
are then classified according to a multi-dimensional framework to synthesize the state of the research in technology evaluation
and ultimately discover interesting patterns.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
93.
S Tosi G Mosna G Cazzaniga G Giudici L Kearney A Biondi E Privitera 《Canadian Metallurgical Quarterly》1997,11(9):1465-1468
Juvenile myelomonocytic leukemia (JMML) is a rare disorder of early childhood, to which no recurrent chromosome rearrangement has been yet associated. We report a case where leukemic cells harbored a 46,XX,der(12)t(3;12) (q21 approximately 22;p13.33) karyotype, resulting in partial trisomy of 3q. The origin of chromosome material translocated to chromosome 12 was assessed by chromosome painting using a whole chromosome 3-specific probe. The breakpoint regions were defined by FISH using YAC probes from 3q and 12p chromosomal regions. Interestingly, partial trisomy of 3q has been detected in a previously reported JMML case, consequent to the presence of a der(15)t(3;15)(q13.1;q26). The involvement of a similar chromosome 3 rearrangement in these two JMML cases suggests the hypothesis that either the resulting duplication of some gene/s on 3q or the loss of heterozygosity (LOH) of some gene/s on 3p may be involved in one of the steps leading to JMML. On the other hand, it cannot be ruled out that the relevant mutation in our case might be consequent to the particular breakpoints at bands 3q21 approximately 22 and 12p13.3, that may alter the structure and/or expression of the involved gene/s. 相似文献
94.
This article presents the system WHY, which learns and updates a diagnostic knowledge base using domain knowledge and a set of examples. The a priori knowledge consists of a causal model of the domain that states the relationships among basic phenomena, and a body of phenomenological theory that describes the links between abstract concepts and their possible manifestations in the world. The phenomenological knowledge is used deductively, the causal model is used abductively, and the examples are used inductively. The problems of imperfection and intractability of the theory are handled by allowing the system to make assumptions during its reasoning. In this way, robust knowledge can be learned with limited complexity and a small number of examples. The system works in a first-order logic environment and has been applied in a real domain. 相似文献
95.
96.
The empirical investigation of Perspective-Based Reading 总被引:6,自引:1,他引:5
Victor R. Basili Scott Green Oliver Laitenberger Filippo Lanubile Forrest Shull Sivert Sørumgård Marvin V. Zelkowitz 《Empirical Software Engineering》1996,1(2):133-164
We consider reading techniques a fundamental means of achieving high quality software. Due to the lack of research in this area, we are experimenting with the application and comparison of various reading techniques. This paper deals with our experiences with a family of reading techniques known as Perspective-Based Reading (PBR), and its application to requirements documents. The goal of PBR is to provide operational scenarios where members of a review team read a document from a particular perspective, e.g., tester, developer, user. Our assumption is that the combination of different perspectives provides better coverage of the document, i.e., uncovers a wider range of defects, than the same number of readers using their usual technique.To test the effectiveness of PBR, we conducted a controlled experiment with professional software developers from the National Aeronautics and Space Administration/Goddard Space Flight Center (NASA/GSFC) Software Engineering Laboratory (SEL). The subjects read two types of documents, one generic in nature and the other from the NASA domain, using two reading techniques, a PBR technique and their usual technique. The results from these experiments, as well as the experimental design, are presented and analyzed. Teams applying PBR are shown to achieve significantly better coverage of documents than teams that do not apply PBR.We thoroughly discuss the threats to validity so that external replications can benefit from the lessons learned and improve the experimental design if the constraints are different from those posed by subjects borrowed from a development organization. 相似文献
97.
Girardin Fabien Calabrese Francesco Fiore Filippo Dal Ratti Carlo Blat Josep 《Pervasive Computing, IEEE》2008,7(4):36-43
Novel methods and tools are being developed to explore the significance of the new types of user-related spatiotemporal data. This approach helps uncover the presence and movements of tourists from cell phone network data and the georeferenced photos they generate. 相似文献
98.
A method for the quantitative determination of propranolol and two of its active metabolites, 3-(alpha-naphthoxy)-1,2-propanediol (propranolol glycol) and N-des-isopropylpropranolol, in brain tissue of mice is described. Tissues are homogenized in perchloric acid-acetonitrile. Propranolol and its metabolites are isolated from the supernatant by solvent extraction and separated and detected as their trifluoroacetyl derivatives by electron capture gas chromatography. Chemical structures of the derivatives were confirmed by gas chromatography-mass spectrometry. The electron capture detector response of all three compounds is high, 0.7-2.0 X 10(-16) moles/sec. Brain levels of 10-250 ng/g can be detected of all three compounds with high specificity and good precision. 相似文献
99.
The use of a general correlation, proposed for organic liquid thermal conductivity λ prediction and checked in the case of organic refrigerant fluids, is extended to inorganic refrigerant fluids whose λ decreases when the reduced temperature, Tr, increases. Suggestions are given for the refrigerants fluids whose λ increases with the reduced temperature. 相似文献
100.
Filippo Romanato Husen Kartasasmita Kang Kwang Hong Lee Gianluca Ruffato Mauro Prasciolu Chee Cheong Wong 《Microelectronic Engineering》2009,86(4-6):573-576
Nonlinear processes involved in the manufacture of nominally sinusoidal surface relief diffraction gratings generated by interference lithography can introduce distortions into the profile of these surfaces. Such distortions may dramatically affect both the specular reflectivity and diffracted efficiencies from such a surface [H. Raether, Phys. Thin Film 9 (1977) 145–261]. We shall consider in particular the case of metallic gratings used to investigate plasmonic effects that can be engineered for bio-sensing applications. To investigate these effects, interference lithography (IL) has been used for the generation of profile controlled sinusoidal plasmonic crystals. IL exposure contrast study has been performed to control the amplitude oscillation and the surface roughness quality. Bi-metallic layer of silver and gold have been systematically deposited with different film thicknesses. A comprehensive numerical model that studies the optical coupling to surface plasmon polaritons on Ag/Au gratings has been undertaken for the simulation of the reflectivity and azimuthal angle dependence [Z. Chen, I.R. Hooper, J.R. Sambles, J. Opt. A: Pure Appl. Opt. 10 (1) (2008) 015007]. This computation illustrates the sensitivity of individual features to specific harmonic components of the surface, for surface plasmon resonances recorded in both the zeroth and higher diffracted orders. The roughness surface control after development and after bi-metallic evaporation strongly contributes to tighten the width of the reflectivity peak. Optimization process has shown that for an Ag (37 nm) and Au (7 nm) metallic bilayer, a semi-amplitude of 20 nm provides the best reflectivity. 相似文献