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991.
Das Amit Kumar Ghosh Sayantani Thunder Samiruddin Dutta Rohit Agarwal Sachin Chakrabarti Amlan 《Pattern Analysis & Applications》2021,24(3):1111-1124
Pattern Analysis and Applications - COVID-19 continues to have catastrophic effects on the lives of human beings throughout the world. To combat this disease it is necessary to screen the affected... 相似文献
992.
Maity Piyali Kumar Ravi Jha S. N. Bhattacharyya D. Singh Ranjan Kumar Chatterjee Sandip Ghosh Anup Kumar 《Journal of Materials Science: Materials in Electronics》2022,33(27):21822-21837
Journal of Materials Science: Materials in Electronics - The tunability of structural, optical, electronic, and magnetic properties in semiconductor quantum dots (QDs) makes them promising... 相似文献
993.
Nasrin Sedaghati Aziz Habibi-Yangjeh Soheila Asadzadeh-Khaneghah Srabanti Ghosh 《Advanced Powder Technology》2021,32(2):304-316
Despite significant advancements in the improvement of heterogeneous photocatalysis towards water treatment, these processes still have some bottlenecks. In this research paper, oxygen vacancy rich-TiO2 was combined with Bi4O5Br2 nanoparticles (denoted as TiO2-OVs/Bi4O5Br2) by eco-friendly hydrothermal approach. The outcomes demonstrated that the photoactivity strongly depends on plenteous active sites, reinforced charge segregation, as well as striking visible-light absorption ability in TiO2-OVs/Bi4O5Br2 nanocomposite with n-n heterojunction. The photoactivity was found to follow the trend: TiO2-OVs/Bi4O5Br2 (30%) > TiO2-OVs > TiO2. Briefly, the removal efficiencies of RhB, MB, and fuchsine were 100%, 96.2%, and 84.7% using TiO2-OVs/Bi4O5Br2 (30%) in 120 min, while they were 25.1%, 20.0%, and 15.3% over the TiO2, respectively. Further, the boosted rate constant was observed for the photoreduction of Cr (VI) on the TiO2-OVs/Bi4O5Br2 (30%) nanocomposite, which was 19.4 and 7.8-folds more than the TiO2 and TiO2-OVs photocatalysts, respectively. The radical scavenging tests with different quenchers demonstrated that holes and superoxide anion radicals take part in the degradation reaction. Finally, by investigating the electrochemical properties, a mechanism was offered to describe the improved e–/h+ pairs separation and migration. This research displayed that the design of n-n heterojunction using TiO2-OVs could be suitable for severely improving photocatalytic performance of TiO2 under visible light. 相似文献
994.
The present study considers friction and wear behavior of aluminum matrix composites reinforced with SiC particles under three different working environments, viz., dry condition, aqueous medium and alkaline medium. The experiments are conducted with a pin-on-disk tribotester where the composite specimen slides against an alumina disk under the application of varying normal load and sliding speed. It is observed that wear increases with increase in applied load and sliding speed for all three working environments and the maximum wear occurs in the case of the alkaline medium followed by the aqueous medium and the dry condition. In general, the friction coefficient decreases with increase in applied normal load. The microstructure analysis of the worn sliding surface is done with the help of a scanning electron microscope and energy dispersive X-ray analysis. It is seen that the wear mechanism in dry condition is dominated by adhesive and abrasive wear while both mechanical and corrosive wear occur in corrosive environments. 相似文献
995.
996.
Abhishek Bhattacherjee Tanushree Ghosh Abhijit Datta 《Journal of Experimental Nanoscience》2018,13(1):50-61
Alternanthera philoxeroides (Mart.), a weed, mainly from tropical origin and easily available worldwide. People used to eat it as a food mainly in South Africa. In our previous report we have thoroughly characterise several important phenolics, monoterpene and phenylpropane from methanol soluble fraction of Alternenthera leaves (fraction X) and also reported their α-glucosidase inhibitory, antimicrobial and antioxidant activities. All these isolated natural compounds are well characterised and widely studied. In our present study we try to use this beneficial fraction (named fraction X) in green synthesis of gold nanoparticles (X-GNP). We also try to explore the beneficial aspects of green synthesis in comparison with commonly used chemical synthesis method (GNP) in context with their antimicrobial activity. UV/Vis spectroscopy, DLS, Zeta potential, FT-IR, EDAX and other microscopic techniques namely: SEM, AFM were used to characterise the synthesised nanoparticles. Different important microbial strains were used to evaluate the antimicrobial activity of prepared nanoparticles. Overall the studies suggest successful synthesis of green nanoparticles (X-GNP) and also showed the improvement in antimicrobial activity of X-GNP nanoparticles. 相似文献
997.
Debojyoti Ghosh Mikhail A. Dorf Milo R. Dorr Jeffrey A. F. Hittinger 《Journal of scientific computing》2018,77(2):819-849
Plasmas with varying collisionalities occur in many applications, such as tokamak edge regions, where the flows are characterized by significant variations in density and temperature. While a kinetic model is necessary for weakly-collisional high-temperature plasmas, high collisionality in colder regions render the equations numerically stiff due to disparate time scales. In this paper, we propose an implicit–explicit algorithm for such cases, where the collisional term is integrated implicitly in time, while the advective term is integrated explicitly in time, thus allowing time step sizes that are comparable to the advective time scales. This partitioning results in a more efficient algorithm than those using explicit time integrators, where the time step sizes are constrained by the stiff collisional time scales. We implement semi-implicit additive Runge–Kutta methods in COGENT, a high-order finite-volume gyrokinetic code and test the accuracy, convergence, and computational cost of these semi-implicit methods for test cases with highly-collisional plasmas. 相似文献
998.
We investigate the excitation behavior of a repulsive impurity doped quantum dot under the influence of an oscillatory external electric field. We have considered Gaussian impurity centers doped at on-center position. The investigation reveals that a variation in the strength and spatial stretch of the dopant causes maximization and minimization in the average excitation rate, respectively. The findings are expected to have important applications involving quantum dot nanodevices. 相似文献
999.
Morphological and rheological footprints corroborating optimum foam processability of PP/ethylene acrylic elastomer blend
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The focus of the present work is optimization of microcellular foam processing of Polypropylene (PP)/ethylene acrylic elastomer blends, through design of experiment approach using Taguchi technique and establishing correlation among foamability, morphological, and rheological parameters of blends. PP and elastomer are melt blended in a twin screw extruder and thereafter foaming parameter optimization is carried out using Taguchi method followed by analysis of variance (ANOVA) for batch foaming setup. Scanning electron microscope reveals development of submicron elastomer domains, which increase with the elastomer content. Further, complex viscosity and van Grup–Palmen plots are found to have a vital role in attaining cellular morphology development in blends. From Taguchi and ANOVA analysis it is established that foaming temperature has a great influence and major contribution on foamability. Blends with low elastomer content are optimized for better foamability using statistical approach and proved to be consistent with the morphological and rheological outcomes. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46322. 相似文献
1000.
Hasan Sk. Md. Ghosh Abhijit Chakrabarti Debalay Singh Shiv Brat 《Metallurgical and Materials Transactions A》2020,51(5):2053-2063
Metallurgical and Materials Transactions A - The present study investigates the orientation dependence of deformation-induced martensite (DIM) transformation in carbide-free bainitic steel using... 相似文献