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A novel tunable current-mode integrator for low-voltage low-power applications is presented using mixed-mode TCAD simulations. The design is based on independently driven double-gate (IDDG) MOSFETs, a nano-scale four-terminal device, where one gate can be used to change the characteristics of the other. Using current-mirrors built with IDDG-MOSFETs, we show that the number of active devices in the tunable current-mode integrator, 16 in bulk CMOS design, may be halved, i.e. considerable savings in both total area and power dissipation. The integrator operates with single supply voltage of 1 V and a wide range of tunable bandwidth (~2 decades) and gain (~30 dB). This linear circuit has third-order harmonic distortion as low as ?70 dB in appropriate bias conditions, which can be set via the back-gates. The impact of tuning on the IDDG integrator and conventional design using symmetrically driven (SDDG) MOSFETs is comparatively studied. The proposed design is a good example for performance leverage through IDDG MOSFET architectures in analog circuits integral to future mixed-signal systems.  相似文献   
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Russian Journal of Non-Ferrous Metals - Additive manufacturing (AM) of the nickel–titanium (NiTi) shape memory alloys (SMA) have provided novel component solutions with a variety of design...  相似文献   
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The present study explores the characteristics of the literature on the algae and bio-energy published during the last three decades, based on the database of Science Citation Index-Expanded (SCIE) and Social Sciences Citation Index (SSCI) and its implications using the scientometric techniques. The results of this work reveal that the literature on the algae and bio-energy has grown exponentially during this period reaching 717 papers in total. Most of document type is in the form of journal articles, reviews, and proceedings, constituting 98% of the total literature and English is the predominant language (97.6%). USA, China, Germany, and England are the four biggest contributing countries on the algae and bio-energy literature publishing, 26%, 8%, 8%, and 8% of the sample, respectively. The Chinese Academy of Sciences is the largest institutional contributor publishing 2.6% of the papers. The most publishing four authors are Wilhelm (13 papers) followed by Wu (15 papers), Mimuro (10 papers), and Zhao (9 papers). “Bioresource Technology” is the most publishing journal with 24 published papers, followed by “Journal of Applied Phycology” (17 papers), and “Biotechnology and Bioengineering” (15 papers). “Biotechnology & Applied Microbiology” is the subject area with 24.3% of the sample published. This is followed by “Energy & Fuels” (16.3%), “Marine & Freshwater Biology” (14.2%), and “Environmental Sciences” (12.3%). The total number of citations is 11,079, giving a ratio for the “Average Citations per Item” as 15.45 and “H-index” as 52. A list of most-cited 25 authors is produced and Chisti (2007) receives 320 citations with 80 total average citations per year. This paper is followed by Lewis and Nocera (2006; 296 citations), Demirbas (2001; 187 citations). Chisti (2007) has the highest impact on the literature on the algae and energy with total average citations per year of 80. This is followed by Lewis and Nocera (2006, 59.8 annual citations) and Chisti (2008, 41 annual citations). An analysis of the citing papers shows the impact of the research on the algae and bio-energy for the related academic disciplines. This provides further incentives for all the stakeholders of the research on the algae and energy, but especially for the researchers and their institutions and their countries to do more research in this area. The results of this first ever such study of its kind show that the scientometric analysis has a great potential to gain valuable insights into the evolution of the research the on algae and bio-energy as in the case of new emerging technologies and processes such as nanoscience and nanotechnology complementing literature reviews, content analysis and metaanalysis research techniques.  相似文献   
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合金结构钢20MnCr5淬透性较好,热处理变形小,低温韧性好,切削加工性能良好,但焊接性较差。可作渗碳件和截面较大、负荷较高的调质件,如齿轮、轴类、蜗杆、套筒、摩擦轮等。干切削和近干切削彻底消除或者极大的减少了冷却液的使用,减少了工业污染,起到了保护环境的作用。论文对合金结构钢20MnCr5在传统乳化剂、干切削和微量润滑条件下进行切削实验,从而比较不同切削参数和润滑方式以及含硫量对刀具所受机械载荷、刀具磨损和工件表面质量的影响,以获得合金机构刚20MnCr5的干切削和近干切削和在微量润滑条件下的性能,为实际的生产加工积累和提供基础数据。  相似文献   
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We aimed at comparing the elderly adults and normal subjects with regard to their disability, psychological status, and quality of life (QOL). One hundred and twenty-five dialysis patients and 61 controls were recruited in the study. Depression and anxiety symptoms of the patients were evaluated with the Psychological Symptom Screening List (SCL 90-R). For evaluating the disability, the Rivermead mobility index (RMI) was utilized. For evaluating the QOL, we used the short form-36 (SF-36) scale. The Rivermead mobility index of the patients (9.6 +/- 3.4) was found. When compared with controls, dialysis patients had higher levels of disability (p = 0.0001). Depression and anxiety symptom scores of these patients were also significantly higher than that of the controls (p < 0.05). There was a correlation between the disability and depression symptom scores (r: 0.171, p = 0.037). Both physical and mental capacity scores of the dialysis patients were lower than those of the controls (p < 0.05 and p < 0.05) QOL scores for elderly hemodialysis patients were found to be lower. Their disability was higher, making them dependable on others during their daily lives. Specific exercise programs should be developed for these patients. Even the smallest effort in this regard will result in improvements in physical functioning while bringing them significant benefits.  相似文献   
58.
We present an efficient simulation approach to study the universal mobility behaviour in Si MOS structures with random Si/SiO2 interfaces. Our approach is based on 3D Brownian dynamics in devices with realistic Si/SiO2 interfaces reconstructed from a Gaussian or exponential correlation function. The carrier-interface roughness scattering is treated ab-initio in our simulations and it results in correct velocity and real space distributions. The method is efficient and capable of 3D simulation of the interface roughness limited mobility in small MOSFETs in a statistical manner. After a careful calibration procedure, we reproduce the effective field dependence of interface mobility for Bulk = 1100 cm2/Vs using a random interface with single atomic steps and a correlation length of 6 nm.  相似文献   
59.
The adsorption of polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) by activated carbon (AC) was examined in a fixed-bed AC unit in a hazardous waste incinerator (IZAYDAS) in Turkey. Results showed that the removal efficiencies of PCDD/Fs decrease as the chlorination level increases, which was explained by the difference in gas/particle partitioning of the compounds. Since dioxins are tightly adsorbed by activated carbon, other flue gas constituents showed no clear effect on the dioxin removal. Adsorption kinetics indicated that the adsorption of volatile congeners and homologues fits well with Henry's law, possibly due to the higher gaseous fractions, while the correlation was lower for lowly volatile ones. PCDD/F congeners and homologues had a concentration value up to which no adsorption occurred, which could be attributed to the insufficient contact times at the low concentrations.  相似文献   
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论述了汽车防抱死制动系统的概念,分析了ABS的工作原理,并通过对具体的一种车型ABS的性能进行检测、分析,得出了该车型ABS能够达到预定的要求,并起到作为汽车安全附加装置的目的。  相似文献   
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