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891.
892.
893.
90 male and female college students learned a list of 28 declarative sentences and rated the sentences for imagery or pronounceability. Ss were given either verbatim or paraphrased test questions during acquisition and were tested with a 2nd paraphrased question on the retention test. Imagery instructions and paraphrased acquisition questions, which guided subsequent encoding of the sentences, produced superior retention. Levels-of-processing ideas and the encoding specificity principle were invoked to explain these results. Finally, paraphrased test questions did, but imagery rating did not, increase the conditional probability of a correct recall on the retention test given a correct recall during acquisition. This latter result seems to support A. Paivo's (1974) dual process theory of memory. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
894.
The general decline of radical empiricism has led to a renewed appreciation of the role of nonempirical contributions to the advancement of science. In psychology, this has meant the development of a theoretical wing comparable to the well-established theoretical traditions that exist in other scientific disciplines. Theoretical psychology is no longer the collection of vague generalities that once made up the traditional "systems and theories" course. It is an active subdiscipline with a well-articulated research program and a growing corpus of special methods and results. This article surveys the types of issues dealt with by theoretical psychologists and discusses the relation between their work and empirical research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
895.
[Correction Notice: An erratum for this article was reported in Vol 121(6) of Behavioral Neuroscience (see record 2007-18058-034). Figure 4 on p. 96 (Results and Discussion, Experiment 2: Behavioral section) was incorrect. The correct figure is provided in the erratum.] The present study examined the effects of neurotoxic lesions of the central nucleus (CNA) and basolateral complex (BLA) of the amygdala on conditioned taste aversion (CTA) in a latent inhibition design. In Experiment 1, lesions of the CNA were found to have no affect on CTA acquisition regardless of whether the taste conditioned stimulus (CS) was novel or familiar. Lesions of the BLA, although having no influence on performance when the CS was familiar, retarded CTA acquisition when the CS was novel in Experiment 2. The pattern of results suggests that the CTA deficit in rats with BLA lesions may be a secondary consequence of a disruption of perceived stimulus novelty. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
896.
Reports an error in "Effects of Central and Basolateral Amygdala Lesions on Conditioned Taste Aversion and Latent Inhibition" by Justin St. Andre and Steve Reilly (Behavioral Neuroscience, 2007[Feb], Vol 121[1], 90-99). Figure 4 on p. 96 (Results and Discussion, Experiment 2: Behavioral section) was incorrect. The correct figure is provided in the erratum. (The following abstract of the original article appeared in record 2007-02025-008.) The present study examined the effects of neurotoxic lesions of the central nucleus (CNA) and basolateral complex (BLA) of the amygdala on conditioned taste aversion (CTA) in a latent inhibition design. In Experiment 1, lesions of the CNA were found to have no affect on CTA acquisition regardless of whether the taste conditioned stimulus (CS) was novel or familiar. Lesions of the BLA, although having no influence on performance when the CS was familiar, retarded CTA acquisition when the CS was novel in Experiment 2. The pattern of results suggests that the CTA deficit in rats with BLA lesions may be a secondary consequence of a disruption of perceived stimulus novelty. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
897.
Among consumers, heat-treated wood recently gained more importance due its attractive darker color along with several other advantages such as improved biological resistance, dimensional stability, and thermal insulating properties. However, exposure to the exterior environment drastically changes the attractive darker color of this product. From dark brown, it becomes almost white. For this reason, development of a nontoxic transparent coating which can protect the heat-treated wood from photodegradation is very important. Addition of UV stabilizers (UV absorbers, HALS, antioxidant) is necessary for transparent coatings in order to filter the harmful UV/VIS radiation. In this present study, the effectiveness of natural antioxidants, extracted from conifer barks or needles from trees in protecting the color of wood, as additives to acrylic polyurethane coating is examined. Also, their UV/VIS absorption capacities and semi-quantitative component analyses have been presented. The toxicity of these new products was also evaluated on human normal skin cells due to ever increasing environmental legislation. The chemical modification of acrylic polyurethane coating containing conifer bark and needle extract were examined by ATR–FTIR analysis. Promising results were obtained for these natural antioxidants which showed very high UV absorption characteristics and antioxidant activity.  相似文献   
898.
One of the versions of the plasma–metal inert gas (MIG) process is basically a combination of a plasma arc with a MIG/metal active gas (MAG) arc in a single torch. With this association, the advantages of each arc are combined. The main characteristic of this is the independence between the heat input by the process and the deposited material, resulting in greater facility to control bead weld geometry. In the current literature, there is a shortage of information related to the process, and most of this goes back to the 1970s and 1980s when the technology available was not able to make the process viable for industry. However, in recent years, the use of the diffusion of new electronic power sources used in welding has sparked up again the interest in plasma–MIG process. In this context, this paper aims to contribute to the studies related to the influence of the MIG and plasma current balance on the geometry of the bead weld and wire fusion rate. Bead-on-plate welds were carried out with plasma and MIG/MAG current combinations at three levels each, keeping, by welding speed corrections, the bead volume the same. It was observed that the introduction of the plasma current over the MIG/MAG current reduces penetration and dilution and leads to convex beads. On the other hand, the use of plasma current increases the MIG/MAG wire fusion rate. However, it seems that the intensity of the plasma current is not the governing parameter of those changes.  相似文献   
899.
900.
We report the use of electrospray ionization tandem mass spectrometry (ESI-MS/MS) as a tool for rapid screening of structurally related chemicals toward oligonucleotides using the binding of five bromobenzoquinones with single-stranded (ss) and double-stranded (ds) oligonucleotides (ODNs) as a model. We found that these compounds interact differentially with oligonucleotides depending on the extent of their bromination and methylation. Three dibromobenzoquinones, 2,6-dibromo-1,4-benzoquinone (2,6-DBBQ), 2,5-dibromo-1,4-benzoquinone (2,5-DBBQ), and 2,5-dimethyl-3,6-dibromo-1,4-benzoquinone (DMDBBQ), bound to ssODN to form 1:1 adducts, and the binding constant of DMDBBQ bound to ssODN was 100-fold lower than those of 2,6-DBBQ and 2,5-DBBQ to ssODN, indicating that methyl groups hindered interactions of the bromoquinones with ODNs. Collision-induced dissociation (CID) of the 1:1 and 1:2 adducts of ODN with 2,6-DBBQ and 2,5-DBBQ demonstrated neutral loss of DBBQ and charge separations. Incubation of two tetrabromobenzoquinones (TBBQ), 2,3,5,6-tetrabromo-1,4-benzoquinone and 3,4,5,6-tetrabromo-1,2-benzoquinone, with the same ODNs did not form any adducts of TBBQ with ssODN or dsODN; however, bromide-ODNs were detected. Fragmentation of the bromide-ODN adducts showed loss of the HBr molecule, supporting the presence of bromide on ODNs. High-resolution MS and MS/MS analysis of the mixtures of dinucleotides (AA, GG, CC, and TT) and TBBQ confirmed the presence of bromide on the dinucleotides, supporting the transfer of bromide to ODNs through interaction with TBBQ. This study presents evidence of differential interactions of structurally related bromo and methyl-benzoquinones with oligonucleotides and demonstrates a potential application of ESI-MS/MS analysis of chemical interactions with ODN for rapid screening of the reactivity of other structurally related environmental contaminants toward DNA.  相似文献   
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