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11.
This paper reports the synthesis of various molar concentrations of manganese (Mn)-doped Ultra-High Surface area Activated Carbon (USAC) additives and their efficient use as cathode materials for supercapacitors. We synthesized the nanoparticles via a novel and facile dip-coating process and characterized them in detail by various analytical techniques. The SEM, EDAX, and XPS results showed that the Mn ions were successfully substituted on the USAC additives’ layered structure without any structural changes. The long cyclic stability of the as-prepared Mn-doped USAC additives was tested as a cathode material for supercapacitors at different current densities. The detailed experimental results showed that the Mn dopant content crucially determines the electrochemical performances of the USAC additives. Electrochemical measurements showed that the MnCEP-S600HTT with 0.10 mol% molar concentration of Mn dopant gives the best cycling performances. It delivers a discharge capacity of 262.9 mAh g?1 after 100 cycles. Further increasing the current density to 1000 mA g?1 allowed it to still maintain 253.6 mAh g?1 after 200 cycles. We confirmed that the structure of Mn-doped USAC additives is an important pole to improve the structural stability and electrochemical properties.  相似文献   
12.
Breath alcohol analyser is used to detect alcohol content in end-expiratory breaths in order to enforce driving regulations under the influence of alcohol legislation. The accuracy and reliability of the routine measurements of alcohol content performed with breath alcohol analyser can be achieved by the calibration of the breath alcohol analyser using standards traceable to SI reference material. Proper calibration is essential for transparency in legal verification for which reference material is needed. At international level, a number of NMIs are active to address this important measurement issue of providing accurate measurements. Several international key comparison programs have been organized so far for the determination of ethanol content in aqueous and in nitrogen/air matrix. NIST, USA; BAM, Germany; IRMM, Belgium, Portugal, INMETRO, Brazil, LGC, UK etc. have developed certain reference materials of ethanol in water solution/air with different concentration ranges. However, no such reference material is introduced in India as an indigenous standard, rather, being procured from abroad or using high purity alcohol for calibration purposes. CSIR-NPL, India, being the NMI is now focusing on establishing the calibration facility and development of SI traceable aqueous alcohol standard to provide test reliability for the testing in breath alcohol analyser. This program has a societal impact which contributes to human health and regulatory needs for the nation.  相似文献   
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14.
Abstract— A processing technology based upon a temporary bond—debond approach has been developed that enables direct fabrication of high‐performance electronic devices on flexible substrates. This technique facilitates processing of flexible plastic and metal‐foil substrates through automated standard semiconductor and flat‐panel tool sets without tool modification. The key to processing with these tool sets is rigidifying the flexible substrates through temporary bonding to carriers that can be handled in a similar manner as silicon wafers or glass substrates in conventional electronics manufacturing. To demonstrate the power of this processing technology, amorphous‐silicon thin‐film‐transistor (a‐Si:H TFT) backplanes designed for electrophoretic displays (EPDs) were fabricated using a low‐temperature process (180°C) on bonded‐plastic and metal‐foil substrates. The electrical characteristics of the TFTs fabricated on flexible substrates are found to be consistent with those processed with identical conditions on rigid silicon wafers. These TFTs on plastic exhibit a field‐effect mobility of 0.77 cm2/V‐sec, on/off current ratio >109 at Vds = 10 V, sub‐threshold swing of 365 mV/dec, threshold voltage of 0.49 V, and leakage current lower than 2 pA/μm gate width. After full TFT‐array fabrication on the bonded substrate and subsequent debonding, the flexible substrate retains its original flexibility; this enables bending of the EPD display without loss in performance.  相似文献   
15.
The electrical properties of hafnium oxide (HfO2) gate dielectric as a metal–oxide–semiconductor (MOS) capacitor structure deposited using pulse laser deposition (PLD) technique at optimum substrate temperatures in an oxygen ambient gas are investigated. The film thickness and microstructure are examined using ellipsometer and atomic force microscope (AFM), respectively to see the effect of substrate temperatures on the device properties. The electrical J–V, C–V characteristics of the dielectric films are investigated employing Al–HfO2–Si MOS capacitor structure. The important parameters like leakage current density, flat-band voltage (Vfb) and oxide-charge density (Qox) for MOS capacitors are extracted and investigated for optimum substrate temperature. Further, electrical studies of these MOS capacitors have been carried out by incorporating La2O3 into HfO2 to fabricate HfO2/La2O3 dielectric stacks at an optimized substrate temperature of 800 °C using a PLD deposition technique under oxygen ambient. These Al–HfO2–La2O3–Si dielectric stacks MOS capacitor structure are found to possess better electrical properties than that of HfO2 based MOS capacitors using the PLD deposition technique.  相似文献   
16.
Recently, polyvinyl chloride (PVC) shower hoses have hardened throughout the eastern Shizuoka Prefecture, Japan. According to the elemental analysis results, the carbon and oxygen concentrations were much lower in the damaged hoses. These findings reveal that oxygen-containing, carbon-based plasticisers may leach from the damaged hose. As a result, the hoses lost flexibility after one year of use. The highest number of heterotrophic bacteria was detected by PCR-denaturing gradient gel electrophoresis in the shower water, and the bacterial DNA concentration was higher when hot water contacted the hose surface. I conclude that the plasticiser was leached from the stiffened hose through a bioaccumulation process.  相似文献   
17.
Systematic studies have been carried out on collector-cum-storage type solar water heaters, and efforts were made to minimise heat losses so that this type of water heater can be used for getting hot water at 40°–45°C for taking baths in the early morning hours of the next day. This paper reports year round performace, the performance equation and economics of this new improved solar water heater. This heater can supply 100 litres of hot water at 60°–70°C in the afternoon, and 40°–45°C temperature can be retained till next day morning. Its efficiency is 70.1%.  相似文献   
18.
Multimedia Tools and Applications - Most solitary finger impression check and acknowledgment frameworks / methods are based on the minutiae feature points. Feature Extraction is a fundamental...  相似文献   
19.
In the present work, we report the preparation of lanthanum-modified lead zirconate titanate (PLZT) thin films in pure perovskite phase by RF magnetron sputtering. For this purpose, a 3-in. diameter target of PLZT (8/60/40) was prepared by conventional solid-state reaction route. The chemical composition of PLZT target was determined using gravimetric analysis followed by UV–vis and flame atomic absorption spectrometry. Various deposition parameters such as target-to-substrate spacing, deposition temperature, post-deposition annealing temperature and time have been optimized to obtain PLZT films in pure perovskite phase. The films prepared in pure argon at 100 W RF power without external substrate heating exhibited pure perovskite phase after rapid thermal annealing (RTA) as confirmed by X-ray diffraction (XRD). Compositional analysis of the PLZT film was performed by secondary ion mass spectroscopy (SIMS) using PLZT target as standard sample. Depth profile of the film shows very good stoichiometric uniformity of all elements of PLZT.  相似文献   
20.
We report the first investigation of the frequency dependent effect of 50 MeV Li3+ ion irradiation on the series resistance and interface state density determined from capacitance-voltage (C-V) and conductance-voltage (G-V) characteristics in HfO2 based MOS capacitors prepared by rf-sputtering. The samples were irradiated by 50 MeV Li3+ ions at room temperature. The measured capacitance and conductance were corrected for series resistance. The series resistance was estimated at various frequencies from 1 KHz to 1 MHz before and after irradiation. It was observed that the series resistance decreases from 6344.5 to 322 Ω as a function of frequency before irradiation and 8954-134 Ω after irradiation. The interface state density Dit decreases from 1.12 × 1012 eV−1 cm−2 before irradiation to 3.67 × 1011 eV−1 cm−2 after ion irradiation and further decreases with increasing frequency.  相似文献   
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