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901.
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   
902.
One of the major problems in inverter-fed motors is the high level of audible noise produced by harmonic current and voltage components. To analyze these phenomena the field in the machine airgap is calculated using the rotating field theory together with the Maxwell stress theorem. This analysis yields a way for predicting the spectrum components produced by the motor and for relating it to the airgap flux density distribution time harmonics caused by the nonsinusoidal supply. The theoretical approach is used for calculating the airgap flux density distribution and the frequency spectrum components of a small three-phase squirrel-cage induction motor fed by a six-step voltage source inverter (VSI) and by a pulsewidth-modulated (PWM) inverter. The theoretical results are compared with experiments.  相似文献   
903.
In the past two decades, microfluidics‐based particle production is widely applied for multiple biological usages. Compared to conventional bulk methods, microfluidic‐assisted particle production shows significant advantages, such as narrower particle size distribution, higher reproducibility, improved encapsulation efficiency, and enhanced scaling‐up potency. Herein, an overview of the recent progress of the microfluidics technology for nano‐, microparticles or droplet fabrication, and their biological applications is provided. For both nano‐, microparticles/droplets, the previously established mechanisms behind particle production via microfluidics and some typical examples during the past five years are discussed. The emerging interdisciplinary technologies based on microfluidics that have produced microparticles or droplets for cellular analysis and artificial cells fabrication are summarized. The potential drawbacks and future perspectives are also briefly discussed.  相似文献   
904.
905.
Dentin irradiation with erbium lasers has been reported to alter the composite resin bond to this treated surface. There is still a lack of studies reporting the effect of erbium lasers on dentin organic content and elucidating how laser treatment could interfere in the quality of the resin-dentin interface. This study aimed to evaluate the effect of erbium laser irradiation on dentin morphology and microtensile bond strength (μTBS) of an adhesive to dentin. Seventy-two dentin disks were divided into nine groups (n = 8): G1-Control (600-grit SiC paper); Er:YAG groups: G2- 250 mJ/4 Hz; G3- 200 mJ/4 Hz; G4- 180 mJ/10 Hz; G5- 160 mJ/10 Hz; Er,Cr:YSGG groups: G6- 2 W/20 Hz; G7- 2.5 W/20 Hz; G8- 3 W/20 Hz; G9- 4 W/20 Hz. Specimens were processed for cross-sectional analysis by scanning electron microscopy (SEM) (n = 3), transmission electron microscopy (TEM) (n = 2), and adhesive interface (n = 3). Forty-five dentin samples (n = 5) were restored and submitted to μTBS testing. ANOVA (α = 5%) revealed that G1 presented the highest μTBS values and irradiated groups did not differ from each other. TEM micrographs showed a superficial layer of denatured collagen fibrils. For SEM micrographs, it was possible to verify the laser effects extending to dentin subsurface presenting a rough aspect. Cross-sectional dentin micrographs of this hybridized surface revealed a pattern of modified tags with ringlike structures around it. This in vitro study showed that erbium laser irradiation interacts with the dental hard tissue resulting in a specific morphological pattern of dentin and collagen fibrils that negatively affected the bond strength to composite resin.  相似文献   
906.
A novel amine-based adsorbent for CO? capture from air was developed, which uses biogenic raw materials and an environmentally benign synthesis route without organic solvents. The adsorbent was synthesized through freeze-drying an aqueous suspension of nanofibrillated cellulose (NFC) and N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane (AEAPDMS). At a CO? concentration of 506 ppm in air and a relative humidity of 40% at 25 °C, 1.39 mmol CO?/g was absorbed after 12 h. Stability was examined for over 20 consecutive 2-h-adsorption/1-h-desorption cycles, yielding a cyclic capacity of 0.695 mmol CO?/g.  相似文献   
907.
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   
908.
The present study is concerned with an enhanced fracture mechanics characterization of engineering materials using small scale cruciform bending specimens. Based on the regular SE(B) specimen geometry with a shallow crack, two additional loading legs allow the application of an additional stress component acting longitudinally to the crack front. Compared to standard specimen types, the biaxial loading conditions for the cruciform specimens are in general closer to the situation in pressurized vessels and pipes, especially under thermal shock loading conditions. In a combined experimental and numerical approach, detailed assessments of the local stress and strain fields in comparison to the crack front stress and strain states of standard specimens with deep and shallow cracks are provided. The cruciform bending specimen geometry is demonstrated to be suitable even in small scale dimensions. It permits the application of different combined external loading situations and thus a fracture assessment under conditions close to various situations in engineering application. Due to its small size, the specimen geometry can be employed even if only a limited amount of material is available.  相似文献   
909.
910.
Synthesis of atomically thin MoS2 layers and its derivatives with large‐area uniformity is an essential step to exploit the advanced properties of MoS2 for their possible applications in electronic and optoelectronic devices. In this work, a facile method is reported for the continuous synthesis of atomically thin MoS2 layers at wafer scale through thermolysis of a spin coated‐ammonium tetrathiomolybdate film. The thickness and surface morphology of the sheets are characterized by atomic force microscopy. The optical properties are studied by UV–Visible absorption, Raman and photoluminescence spectroscopies. The compositional analysis of the layers is done by X‐ray photo­emission spectroscopy. The atomic structure and morphology of the grains in the polycrystalline MoS2 atomic layers are examined by high‐angle annular dark‐field scanning transmission electron microscopy. The electron mobilities of the sheets are evaluated using back‐gate field‐effect transistor configuration. The results indicate that this facile method is a promising approach to synthesize MoS2 thin films at the wafer scale and can also be applied to synthesis of WS2 and hybrid MoS2‐WS2 thin layers.  相似文献   
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