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31.
Experiments were conducted to study the performance, emission and combustion characteristics of a DI diesel engine using poon oil-based fuels. In the present work, poon oil and poon oil methyl ester are tested as diesel fuels in Neat and blended forms. The blends were prepared with 20% poon oil and 40% poon oil methyl ester separately with standard diesel on a volume basis. The reductions in smoke, hydrocarbon and CO emissions were observed for poon oil methyl ester and its diesel blend along with increased NOx emission compared to those of standard diesel. However, a reduction in NOx emission and an increase in smoke, hydrocarbon and CO emissions were observed for Neat poon oil and its diesel blend compared to those of standard diesel. The 40% poon oil methyl ester blend showed a 2% increase in brake thermal efficiency compared to that of standard diesel, whereas other fuels tested showed a decreasing trend. From the combustion analysis it was found that ignition delay was shorter for all fuels tested compared to that of standard diesel. The combustion characteristics of poon oil methyl ester and its diesel blend closely followed those of standard diesel.  相似文献   
32.
Sasikaladevi  N.  Geetha  K.  Revathi  A.  Mahalakshmi  N.  Archana  N. 《Multimedia Tools and Applications》2019,78(13):18339-18361
Multimedia Tools and Applications - Rapid growth in the mobile technology manifolds the usage of mobile devices. It leads to the development and popularity of mobile application in diversified...  相似文献   
33.
Multimedia Tools and Applications - Hyper Elliptic Curve Cryptography (HECC) offers comparable security as that of Elliptic Curve Cryptography (ECC) even with much reduced key size. This reduction...  相似文献   
34.
A systematic study of thermal properties such as the Debye temperature, specific heat coefficient, Grüneisen constant, electron-phonon coupling constant and transition temperature have been carried out using the results of electronic band structure and related characteristics, for hafnium superconducting alloys, namely, HfTc2, HfRe2 and HfOs2. Computation of the electronic band structure and associated properties has been carried out using the tight-binding-linear-muffin-tin-orbital (TBLMTO) method within atomic sphere approximation (ASA). The calculated values have been compared with the available results of literature data.  相似文献   
35.
An efficient MapReduce Algorithm for performing Similarity Joins between multisets is proposed. Filtering techniques for similarity joins minimize the number of pairs of entities joined and hence improve the efficiency of the algorithm. Multisets represent real-world data better by considering the frequency of its elements. Prior serial algorithms incorporate filtering techniques only for sets, but not multisets, while prior MapReduce algorithms do not incorporate any filtering technique or inefficiently and unscalably incorporate prefix filtering. This work extends the filtering techniques, namely the prefix, size and positional to multisets, and also achieves the challenging task of efficiently incorporating them in the shared-nothing MapReduce model, thereby minimizing the pairs generated and joined, resulting in I/O, network and computational efficiency. A technique to enhance the scalability of the algorithm is also presented as a contingency need. Algorithms are developed using Hadoop and tested using real-world Twitter data. Experimental results demonstrate unprecedented performance gain.  相似文献   
36.
The significance of this study is the complete replacement of diesel fuel with bio-fuels. For this purpose; bio-fuels, namely, methyl ester of paradise oil and eucalyptus oil were chosen and used as fuel in the form of blends. Various proportions of paradise oil and eucalyptus oil are prepared on a volume basis and used as fuels in a single cylinder, four-stroke DI diesel engine, to study the performance and emission characteristics of these fuels. In the present investigation a methyl ester derived from paradise oil is considered as an ignition improver. The results show a 49% reduction in smoke, 34.5% reduction in HC emissions and a 37% reduction in CO emissions for the Me50–Eu50 blend with a 2.7% increase in NOx emission at full load. There was a 2.4% increase in brake thermal efficiency for the Me50–Eu50 blend at full load. The combustion characteristics of Me50–Eu50 blend are comparable with those of diesel.  相似文献   
37.
In the present work, a normal diesel engine was modified to work in a dual fuel (DF) mode with turpentine and diesel as primary and pilot fuels, respectively. The resulting homogeneous mixture was compressed to a temperature below the self‐ignition point. The pilot fuel was injected through the standard injection system and initiated the combustion in the primary‐fuel air mixture. The primary fuel (turpentine) has supplied most of the heat energy. Usually, in all DF engines, low‐cetane fuels are preferred as a primary fuel. Therefore, at higher loads these fuels start knocking and deteriorating in performances. Usually, DF operators suppress the knock by adding more pilot‐fuel quantity. But in the present work, a minimum pilot‐fuel quantity was maintained constant throughout the test and a required quantity of diluent (water) was added into the combustion at the time of knocking. The advantages of this method of knock suppression are restoration of performance at full load, maintenance of the same pilot quantity through the load range and reduction in the fuel consumption at full load. From the results, it was found that all performance and emission parameters of turpentine, except volumetric efficiency, are better than those of diesel fuel. The emissions like CO, UBHC are higher than those of the diesel baseline (DBL) and around 40–45% reduction of smoke was observed at 100% of full load. The major pollutant of diesel engine, NOx, was found to be equal to that of DBL. From the above experiment, it was proved that approximately 80% replacement of diesel with turpentine is quite possible. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
38.
Using coupled mode theory, we have studied the output intensity profile of Cerenkov second-harmonic radiation from planar waveguides as a function of the propagation distance. In particular, we have obtained the variation of the intensity profile taking into account the effect of prism coupling as well as propagation loss, and have shown that the second-harmonic radiation evolves into a beam-like output. Results of the measured intensity profile of the second-harmonic radiation in proton-exchanged planar waveguides in Z-cut LiNbO3 are also presented that are consistent with the theory  相似文献   
39.
Mahalakshmi  D.  Saranya  J.  Benhiba  F.  Warad  I.  Zarrouk  A.  Chitra  S. 《Journal of Applied Electrochemistry》2021,51(9):1323-1344

To diminish corrosion which leads to structural damages and to implement a green mitigator has induced the usage of aminothiazolyl coumarin derivatives to study mild steel (MS) corrosion using potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), weight loss, atomic force microscopy (AFM), and electron microscopy with energy dispersive spectroscopy (SEM–EDS) spectrometry in acid medium. The results showed that the inhibition efficiency was 90.8% for the least effective inhibitor and 97.1% for the most effective inhibitor at optimal concentration (10 mM). Enhancement of inhibition efficiency in weight loss method and increase in Rp values in impedance and mixed nature of the inhibition in polarization measurement reveals the best inhibition capacity of coumarins over the MS. The coumarins were characterized using FT-IR, NMR and Mass spectroscopy. The adsorption was well fitted with the Langmuir adsorption isotherm model. SEM–EDS and AFM images confirmed the shielding effect of coumarin derivatives through a layer formation on MS against acid medium. The adsorption mechanism of aminothiazolyl coumarin derivatives was further explored by quantum chemical calculations (DFT) and molecular dynamics (MD).

Graphic abstract
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40.
    
The CuO nanoparticle doped poly(vinyl alcohol) (PVA) nanocomposite films were prepared by the solution casting method. The structure of the prepared CuO nanoparticles and PVA nanocomposite films were confirmed by FTIR spectroscopy and XRD. The (101) crystal plane of PVA was observed at 19.8° in XRD. The size of the CuO nanoparticles was determined as 20 nm using Scherrer's formula. It was further confirmed with HRTEM. The surface morphology of the nanocomposite films was investigated using SEM. The optical properties of the prepared CuO nanoparticles and PVA nanocomposite films were analyzed by UV–Visible spectroscopy. The band gap of PVA was decreased after the incorporation of CuO in PVA. The thermal stability of the pure PVA and its nanocomposites was examined using TGA to assess their thermal degradation temperature at five different heating rates. The thermal stability of PVA nanocomposites was increased as compared with pure PVA. The non‐isothermal degradation kinetic studies were also carried out to determine the energy of activation (Ea) for the degradation process using four different kinetic models. The tensile strength and Young's modulus of PVA nanocomposite films were notably increased with the increasing concentration of CuO nanoparticles. POLYM. COMPOS., 40:3737–3748, 2019. © 2019 Society of Plastics Engineers  相似文献   
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