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991.
Densely stacked silicon nanocrystal layers embedded in the gate oxide of MOSFETs are synthesized with Si ion implantation into an SiO/sub 2/ layer at an implantation energy of 2 keV. In this letter, the memory characteristics of MOSFETs with 7-nm tunnel oxide and 20-nm control oxide at various temperatures have been investigated. A threshold voltage window of /spl sim/ 0.5 V is achieved under write/erase (W/E) voltages of +12 V/-12 V for 1 ms. The devices exhibit good endurance up to 10/sup 5/ W/E cycles even at a high operation temperature of 150/spl deg/C. They also have good retention characteristics with an extrapolated ten-year memory window of /spl sim/ 0.3 V at 100/spl deg/C. 相似文献
992.
An insight into cathode options for microbial fuel cells. 总被引:1,自引:0,他引:1
O Lefebvre A Al-Mamun W K Ooi Z Tang D H C Chua H Y Ng 《Water science and technology》2008,57(12):2031-2037
Microbial fuel cell (MFC) is an emerging and promising technology, particularly in the field of wastewater treatment. The MFC capability of achieving organic removal and generating in situ electricity could make it an attractive alternative wastewater treatment technology over conventional treatment technologies. However, MFC is still far from being economically viable, especially because of the cost of the platinum (Pt) catalyst that makes possible the reaction at the cathode. In this study, we tested alternative cathode catalysts, namely sputter-deposited Cobalt (Co) and denitrifying bacteria (biocathode). The performance of these innovative cathodes was compared with that of classic Pt-cathodes. Co competed well with Pt, but further research is still required for biocathodes. However, biocathodes MFC have showed promise. 相似文献
993.
WH Cheung JCY Ng G Mckay 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2003,78(5):562-571
The removal of copper ions from aqueous effluents by chitosan was studied in equilibrium and agitated batch contacting systems. The sorption capacities of chitosan for copper ions are 1.26 and 1.12 mmol g?1 at pH 3.5 and 4.5, respectively. The equilibrium experimental data were best correlated by the Langmuir equation. The kinetics of sorption were studied at an initial solution pH of 4.5 and a chitosan particle size of 355–500 µm. The kinetics were analyzed using four models: the pseudo‐first‐order, pseudo‐second‐order, modified second‐order and Elovich equations. The rate parameters for the four models were determined and the Elovich equation provided the best correlation of the experimental kinetic data. Copyright © 2003 Society of Chemical Industry 相似文献
994.
In this communication we report our study on using high-temperature superconductors as partial oxidation catalysts. We have also investigated fluorinated superconducting materials, since the presence of a strong oxidizing agent should favor partial oxidation selectivities. 相似文献
995.
Low-energy (550 eV) argon-ion beam was used to bombard directly, the backsurface of nitrided n-MOSFET's after the completion of all conventional nMOS processing steps. The interface characteristics and inversion layer mobility of the MOS devices were investigated. The results show that, as bombardment time increases, interface state density and fixed charge density decrease first, and then the change slows down or even turns around. Correspondingly, the carrier mobility and drain conductance of the MOS devices are found to enhance first, and then saturate or turn around. Therefore, this simple technique, which is readily compatible with existing IC processing, is effective for restoring some of the lost device performance associated with gate-oxide nitridation 相似文献
996.
In this article, I review various causes of exogenous myoglobinuria(MU) and its pathogenesis in 26 consecutive patients admitted to emergency room, Asan Medical Center and determine whether there is a relationship between concentration of urine myoglobin(Mb) and acute renal failure(ARF) as a complication of MU. Serum and urine Mb were measured by RIA using myoglobin kit(Daiichi, Inc., Tokyo, Japan). The most common disorder of MU was septic shock with hypotension, followed by crush syndrome, major arterial occlusion by thormbosis, alcohol intoxication with status epilepticus, intoxication of unidentified snake venom and drug ingestion. On the basis of this limited amount of data, there is a significant association between high concentration in urine Mb(> 300 ng/ml) and ARF(Fisher's exact test, p < 0.005). To minimize the chances of development of ARF, routine urine Mb levels should be checked on patients at risk, especially septic shock with hypotension. 相似文献
997.
W.C. Ng H.L. Seet K.S. Lee N. Ning W.X. Tai M. Sutedja J.Y.H. Fuh X.P. Li 《Journal of Materials Processing Technology》2009,209(9):4434-4438
An innovative dry electroencephalography (EEG) electrode has been successfully designed and tested, in which multiple micro-spike electrodes, each of them consisting of a micro-pillar with a micro-tip on top of it, were designed to pass through the hairs and establish electrical conduction at the skin-electrode interface by penetrate into the stratum corneum of the skin. For hygiene reasons, such electrodes should be made disposable, at the same time, should be cost effective. Therefore, a mass production technology, including the processing methods, such as casting, has to be designed and developed. In this project, the micro-spike dry electrodes were fabricated by a vacuum casting method using a master pattern piece made by CNC micro-machining, in which silicone rubber moulds are created and then used to vacuum cast polyurethane (PU), epoxy or epoxy-carbon micro-spike electrodes. In order to obtain a harder polymeric material, varying amount of carbon fillers were added to the epoxy resin, and the hardness of the resulting material were measured and compared. It was found that a higher concentration of added carbon fillers resulted in a harder cast polymer composite. Further to the vacuum casting, to create an electrically conductive layer on the vacuum-casted electrode, an Ag/AgCl electroless deposition method has been developed. The sputtering of the conductive layer was also carried out for comparison. The developed micro-spike electrodes showed better performance in terms of the impedance level and stability as well as a much higher efficiency in EEG measurement. 相似文献
998.
High-performance capillary electrophoresis (HPCE) with UV absorbance detection (254 nm) has been applied for analyzing intracellular free ribonucleotides. The nucleotide profiles obtained from peripheral blood lymphocytes differ from those obtained from Molt4 human leukemic cells. With a 140 mM borate buffer, pH 9.4, a nearly complete profile can be obtained in 25 min. HPCE has comparable resolution to that of high-performance liquid chromatography (HPLC) but is faster in terms of time per sample run (25 min vs 45 min) and requires much less sample (nanoliter range for HPCE vs microliter range for HPLC). 相似文献
999.
Ng H.W. Hasegawa R. Lee A.C. Lowdermilk L.A. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1991,79(11):1608-1623
The authors present a summary of activities in the development of amorphous metals, the development of amorphous core distribution transformer, and the future potential of amorphous materials and transformers. Amorphous metals possess unique properties. Made by rapid quenching of liquid metal, the metal has atoms arranged in a random fashion, making the material easy to magnetize. Transformers made using amorphous materials for cores exhibit losses that are 60%-70% less than comparable transformers made with silicon iron cores. The application of amorphous alloys in transformer designs is described, highlighting some theoretical points about the material as well as practical information about transformer design 相似文献
1000.
Performance Comparison of Bug Navigation Algorithms 总被引:1,自引:0,他引:1
The Bug algorithm family are well-known robot navigation algorithms with proven termination conditions for unknown environments.
Eleven variations of Bug algorithm have been implemented and compared against each other on the EyeSim simulation platform.
This paper discusses their relative performance for a number of different environment types as well as practical implementation
issues. 相似文献