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Cerium‐doped lutetium aluminum garnet (LuAG:Ce) and yttrium aluminum garnet (YAG:Ce) transparent ceramics of same dimension were fabricated and their optical and scintillation properties were studied. LuAG:Ce transparent ceramic showed higher light yield under UV and X‐ray excitation with respect to YAG:Ce transparent ceramic. YAG:Ce transparent ceramic showed higher light yield under gamma excitation and better energy resolution, which could be due to the considerable amount of slower emission (38.5%) in LuAG:Ce as well as lower optical transparency with respect to YAG:Ce ceramic.  相似文献   
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Somatosensory evoked potential, locomotion and vocalisation upon tail pinch in rats was studied in order to determine whether intrathecal magnesium sulphate administration causes spinal anaesthesia. In Wistar rats with indwelling intrathecal catheters, cortical somatosensory evoked potential was recorded following stimulation via electrodes inserted into the hind paw under chloral hydrate anaesthesia before and after intrathecal administration of 10 microliters of either magnesium sulphate (12.3% or 24.6%) or lignocaine (4% or 8%). Locomotion and vocalisation after tail pinch were tested following intrathecal administration of the same two drugs in conscious rats. Somatosensory evoked potential amplitude was diminished after administration of lignocaine (p < 0.05) but did not change after magnesium sulphate. Latency of P1 was increased by lignocaine and by magnesium sulphate 12.3% (p < 0.05). Although lower extremity paralysis was observed in both groups, its duration with magnesium sulphate was much longer than with lignocaine. Vocalisation was recognised after magnesium sulphate 12.3%, but was not observed after lignocaine 8% during paralysis (p < 0.05). We believe that magnesium sulphate caused motor paralysis, but not complete analgesia.  相似文献   
54.
MAXFLAT FIR low/high pass digital filters are traditionally designed to satisfy the constraints of maximal flatness at the ends of the frequency band. In this paper, we show that by moving the points of flatness to the inner band, halfband filters with narrow transition bands can be realized. This, however, affects the smoothness of their magnitude responses at the ends of the frequency band. We propose a new design of halfband filters having their points of flatness at the middle of the pass and stop bands. The resulting filters have significantly narrow transition bands as compared to the existing MAXFLAT designs, and yet their magnitude responses are quite smooth in the entire frequency band.  相似文献   
55.
Two new Y6 derivatives of symmetrical YBO-2O and asymmetrical YBO-FO nonfullerene acceptors (NFAs) are prepared with a simplified synthetic procedure by incorporating octyl and fluorine substituents onto the terminal 2-(3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (INCN) moiety. By moving the alkyl substituents on the Y6 core to the terminal INCN moiety, the lowest unoccupied molecular orbital of the YBO NFAs increases without decreasing solubility, resulting in high open-circuit voltages of the devices. Molecular dynamics simulation shows that YBO-2O/-FO preferentially form core–core and terminal–terminal dimeric interactions, demonstrating their tighter packing structure and higher electron mobility than Y6, which is consistent with 2D grazing incidence X-ray scattering and space charge limited current measurements. In blend films, the hole transfer (HT) from YBO-2O/-FO to the polymer donor PM6 is studied in detail by transient absorption spectroscopy, demonstrating efficient HT from YBO-FO to PM6 with their suitable energy level alignment. Despite the simplified synthesis, YBO-FO demonstrates photovoltaic performance similar to that of Y6, exhibiting a power conversion efficiency of 15.01%. Overall, this design strategy not only simplifies the synthetic procedures but also adjusts the electrical properties by modifying the intermolecular packing and energy level alignment, suggesting a novel simplified molecular design of Y6 derivatives.  相似文献   
56.
During the past few years the scientific and medical community has been confronted with a continual interest in vitamin E with the interest prompted by new discoveries. Tocopherols and tocotrienols, commonly known as vitamin E, are extremely invaluable compounds and have various nutritional functionalities and benefits to human health. Great deals of research projects have been launched in order to develop effective methods for the extraction of vitamin E. By and large, three distinct extractive methods are usually employed: supercritical fluid extraction (SFE), molecular distillation, and adsorption methods. These methods are sensitive to different experimental conditions, such as pressure, temperature, and flow rate with noticeable effects on the efficiency of the extraction and enrichment of vitamin E. This review has covered the most commonly adapted extraction methods and has probed into the extraction yields under variable operational parameters.  相似文献   
57.
Mobile Networks and Applications - Mobile Ad-hoc Cloud (MAC) is the constellation of nearby mobile devices to serve the heavy computational needs of the resource-constrained edge devices. One of...  相似文献   
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A new wideband asymmetric microstrip coupled-line coupler with 3 dB coupling value and quadrature phase difference is presented. Compared with the conventional edge-coupled couplers, this structure, consisting of two different transmission lines (interdigital and conventional microstrip transmission lines) as coupled lines, achieves wider operating bandwidth and larger coupling level. The coupled-line length of the proposed structure is approximately λg/4. To characterize the structure, an equivalent circuit model has been established. A 3 dB designed and fabricated coupler with 0.2 mm spacing between coupled lines exhibits an amplitude balance of 2 dB from 2.2 GHz to 4.2 GHz. Good agreements between the full-wave simulation and equivalent circuit model results has been achieved and verified the effectiveness of the proposed circuit model. Also, measurement results have been presented.  相似文献   
60.
This study utilizes sugar beet pulp as a low-cost absorbent to remove two different cationic dyes, methylene blue and safranin, in aqueous solutions. The effects of operational parameters on the efficiency of dye removal including pH, adsorbent mass, initial dye concentration and contact time have been investigated. All sets of experiments were carried out in batch mode. For both dyes, the maximum absorption was reached at pH 10 while point zero charge was known to be at pH 6. Boehm method showed that the amount of the acidic and basic groups have been 0.4075 mmol g−1 and 0.0089 mmol g−1, respectively. Freundlich and Langmuir models were used to analyse the obtained experimental data. In comparison, Langmuir model was understood to be a better fit for the experimental data than Freundlich model. Pseudo first-order and pseudo second-order models were used to determine the adsorption kinetics and it was observed that pseudo second-order model was the most suited model for both dyes. The equilibrium state for both dyes was reached after 210 min of the absorption experiment with more than 93% removal of dyes. The absorption capacities were found to be 211 mg/g and 147 mg/g for methylene blue and safranin, respectively.  相似文献   
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