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Mobile Networks and Applications - Changes in the BAN topology are caused due to the body movement induced by repeated activities like walking, running, twisting, turning and waving arms. In such...  相似文献   
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Nano-graphene oxide, nano-(GO), was prepared via a modified Hummer’s method. Hence, superconducting composites of type (GO)x/(Cu0.25Tl0.75)Ba2Ca3Cu4O12?δ, x?=?0.00, 0.25, 0.50, 0.75, 1.00, 1.50 and 2.00 wt%, were prepared via the solid-state reaction technique at 850 °C under ambient pressure. The prepared nano-(GO) was characterized using X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy, transmission electron microscopy, high-resolution transmission electron microscopy and the selected-area electron diffraction pattern. The composites samples of type (GO)x/(Cu0.25Tl0.75)Ba2Ca3Cu4O12?δ were characterized using XRD and scanning electron microscopy. The electrical properties of the prepared samples were investigated using the electrical resistivity measurements. The results showed that the samples retained their superconductivity for all x values with a maximum enhancement in the phase formation, the superconducting transition temperature and the activation energy at x?=?0.75 wt%.

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The present study aims to evaluate the effect of brushing with fluoride dentifrice on teeth severely affected by erosion due to respiratory medicaments. Enamel (n = 50) and dentin (n = 50) bovine specimens were prepared and treated with artificial saliva (S‐control), acebrofilin hydrochloride (AC), ambroxol hydrochloride (AM), bromhexine hydrochloride (BR), and salbutamol sulfate (SS) and subjected to cycles of demineralization (immersing in 3 mL, 1 min, three times a day at intervals of 1 hr, for 5 days) followed by remineralization (saliva, 37°C, 1 hr). Simulated brushing with fluoridated toothpaste was performed using 810 strokes in a reciprocal‐action brushing simulator. Scanning electron microscopy, micro energy dispersive X‐ray fluorescence (μ‐EDXRF) spectroscopy and attenuated total reflection Fourier transform infrared (ATR FTIR) spectroscopy were then performed. μ‐EDXRF images showed extensive erosion after treatment with all medicaments. SEM images showed enamel erosion in order SS > BR > AC = AM > S after brushing and fluoridation. FTIR results were in agreement. In case of dentin, μ‐EDXRF measurements showed significant difference in mineral content (percent weight of calcium and phosphate) in SS + brushing + fluoridation treated enamel compared to control, while μ‐EDXRF images showed erosive effects in the order SS > AM>BR > AC = S post brushing + fluoridation. SEM images showed erosion in the order SS > AM = BR > AC > S post brushing + fluoridation. Again, FTIR multivariate results were in agreement. Overall, our study shows that proper oral care is critical when taking certain medication. The study also demonstrates the possible use of FTIR for rapid clinical monitoring of tooth erosion in clinics.  相似文献   
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Science China Technological Sciences - Magnetoseismology, a technique of magnetic field diagnostics based on observations of magnetohydrodynamic (MHD) waves, has been widely used to estimate the...  相似文献   
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This paper describes the method of determining batch sizes in a multi-product, multi-stage situation and presents a Decision Support System (DSS) for capacity utilization. A heuristic model has been developed for modifying the optimal batch sizes in a manner such that machine hour and labour productivity constraints are not violated. The capacity utilization so determined will also suggest and identify the need for reduction of number of set-ups.  相似文献   
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In this investigation the characteristics of thin wall (3 mm thickness) castings of copper alloyed gray cast iron have been examined. The samples of the thin wall castings have been austempered isothermally thus the thin wall austempered gray iron (TWAGI) produced. The samples austenitizing at 927 °C (1700 °F), the samples have been austempered at 260 °C (500 °F), 285 °C (545 °F), 310 °C (590 °F), 335 °C (635 °F), 360 °C (680 °F) and 385 °C (725 °F) respectively for 1 h. As a result, these samples developed an ausferrite matrix and excellent mechanical properties. The microstructures of these samples TWAGI have been characterized through optical microscopy, scanning electron microscopy and X-ray diffraction analysis. The mechanical properties may be correlated with the volume fraction of austenite and ferrite and ferrite cell size in the ausferrite microstructure.  相似文献   
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The mesoscale, multitier texture of the lotus leaf has served as an inspiration to fabricate surface designs with controllable superhydrophobic properties, targeting a broad range of applications. The choice of material for such designs is directly related to surface performance, in particular under adverse and realistic conditions. Due to its importance in many applications, here aluminium is employed as a material platform and identify key porous hierarchical textures, yielding extraordinary impalement‐resistant behavior: Droplet repellency is demonstrated consistently for water impact velocities up to 12 m s−1 (extreme Weber number, We ≈ 3500). Despite impressive superhydrophobic behavior, if ice forms on such surfaces, ice adhesion is markedly stronger than on less hydrophobic alumina nanotube array structures. In a departure from the findings of the well‐accepted shear stress‐based ice adhesion criterion, a deviation between decreasing ice adhesion strength and increasing hydrophobicity is observed. This is explained with ice adhesion mechanism, depending strongly on the applied stress field orientation and the respective effective ice–substrate contact area. Our results indicate that ice adhesion criteria for the performance of icephobic surfaces should account for the simultaneous presence of shear and tensile stresses, instead of shear stresses alone.  相似文献   
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