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1.
In this paper we present a novel anisotropic diffusion model targeted for 3D scalar field data. Our model preserves material boundaries as well as fine tubular structures while noise is smoothed out. One of the major novelties is the use of the directional second derivative to define material boundaries instead of the gradient magnitude for thresholding. This results in a diffusion model that has much lower sensitivity to the diffusion parameter and smoothes material boundaries consistently compared to gradient magnitude based techniques. We empirically analyze the stability and convergence of the proposed diffusion and demonstrate its de-noising capabilities for both analytic and real data. We also discuss applications in the context of volume rendering.  相似文献   
2.
The metal-induced crystallization (MIC) of hydrogenated sputtered amorphous silicon (a-Si:H) using aluminum has been investigated using X-ray diffraction (XRD) and scanning Auger microanalysis (SAM). Hydrogenated, as well as non-hydrogenated, amorphous silicon (a-Si) films were sputtered on glass substrates, then capped with a thin layer of Al. Following the depositions, the samples were annealed in the temperature range 200 °C to 400 °C for varying periods of time. Crystallization of the samples was confirmed by XRD. Non-hydrogenated films started to crystallize at 350 °C. On the other hand, crystallization of the samples with the highest hydrogen (H2) content initiated at 225 °C. Thus, the crystallization temperature is affected by the H2 content of the a-Si. Material structure following annealing was confirmed by SAM. In this paper, a comprehensive model for MIC of a-Si is developed based on these experimental results.  相似文献   
3.
In this study, novel metallo‐supramolecular materials based on terpyridine‐functionalized polyhedral silsesquioxane were synthesized from 4′‐chloro‐2,2′:6′,2″‐terpyridine and amino‐group‐functionalized polyhedral oligomeric silsesquioxane. The obtained terpyridine‐functionalized polyhedral silsesquioxanes were converted to metallo‐supramolecular hybrid materials by coordination polycondensation reaction with Co(II) or Cu(II) ions. The supramolecular polymers created were characterized by means of structure, morphology and stimuli‐responsive performance employing scanning electron microscopy, amperometric techniques and UV–visible and Fourier transform IR spectroscopy. UV?visible and cyclic voltammetry studies showed that both the optical and electrochemical properties of metallo‐supramolecular materials are affected by the substituent at the pyridine periphery. The supramolecular polymers obtained exhibited electrochromism during the oxidation processes of cyclic voltammogram studies. As a result, these terpyridine‐functionalized polyhedral silsesquioxanes are good candidates for electronic, opto‐electronic and photovoltaic applications as smart stimuli‐responsive materials. © 2013 Society of Chemical Industry  相似文献   
4.
Purple-fleshed sweet potato flour could be used to enhance the colour, flavour and nutrients in food products. Thus, the investigation was to produce encapsulated flours from purple-fleshed sweet potato by spray drying using combinations of various levels of ascorbic acid (5 g kg−1 and 10 g kg−1) and maltodextrin (30 g kg−1 and 100 g kg−1) and to evaluate their effects on bioactive components, physicochemical and morphological properties. Encapsulated flours had higher total phenolic content, antioxidant capacity and water solubility index than non-encapsulated flour. There were no significant differences in anthocyanin content between encapsulated and non-encapsulated flours. However, water absorption index and flavonoids content of encapsulated flours depended on concentrations of ascorbic acid and maltodextrin. In addition, the high concentrations of ascorbic acid and maltodextrin encapsulated flours had higher glass transition temperature as compared to that of lower concentrations. In respect to morphology, the particles of encapsulated flours with high concentration of ascorbic acid and maltodextrin were more aggregated than those encapsulated with lower concentrations. Therefore, flours encapsulated with 10 g kg−1 ascorbic acid and 30 g kg−1 maltodextrin could be used to enhance the antioxidant activities of functional food ingredients.  相似文献   
5.
Dietary fibre components, hydration properties and antioxidant activities such as 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging, reducing power, metal chelating and 2,2′‐azino‐bis,3‐ethyl‐benzo‐thiazoline‐6‐sulphonic acid (ABTS) radical scavenging activities of persimmon peel powders using different washing treatments (tap water at 20 °C and hot water) were investigated. Peel powder obtained from hot water‐washed peels (74.95 g per 100 g) had higher dietary fibre content than tap water‐washed (65.50 g per 100 g) and unwashed (60.99 g per 100 g) peels. The higher content of total phenolic and ascorbic acid were found in peel powder obtained from unwashed peels, whereas washed peels had more β‐carotene content. The EC50 values of scavenging DPPH and ABTS radical for peel powders obtained from unwashed, tap water‐washed and hot water‐washed peels were 75.44, 142.18 and 110.17 μg mL?1 respectively and 5.31, 5.34 and 5.39 μg mL?1 respectively. Therefore, hot water washing is recommended to obtain better quality products from persimmon peel for use as a fibre supplement.  相似文献   
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Translated from Steklo i Keramika, No. 4, pp. 29–31, April, 1992.  相似文献   
9.
Black phosphorus (BP) has recently attracted significant attention due to its exceptional physical properties. Currently, high‐quality few‐layer and thin‐film BP are produced primarily by mechanical exfoliation, limiting their potential in future applications. Here, the synthesis of highly crystalline thin‐film BP on 5 mm sapphire substrates by conversion from red to black phosphorus at 700 °C and 1.5 GPa is demonstrated. The synthesized ≈50 nm thick BP thin films are polycrystalline with a crystal domain size ranging from 40 to 70 µm long, as indicated by Raman mapping and infrared extinction spectroscopy. At room temperature, field‐effect mobility of the synthesized BP thin film is found to be around 160 cm2 V?1 s?1 along armchair direction and reaches up to about 200 cm2 V?1 s?1 at around 90 K. Moreover, red phosphorus (RP) covered by exfoliated hexagonal boron nitride (hBN) before conversion shows atomically sharp hBN/BP interface and perfectly layered BP after the conversion. This demonstration represents a critical step toward the future realization of large scale, high‐quality BP devices and circuits.  相似文献   
10.
ABSTRACT

Memory-resistor (Memristor) has drawn considerable attention of the researchers in the last decade due to its remarkable properties. After the first concept of memristor, proposed by Leon Chua in 1971, almost no research work was conducted in this field for a long time. However, since the revolutionary discovery of the physical structure of memristor and its model of the HP lab in 2008, a tremendous amount of research work has been going on. Researchers are focusing on improving the models for the analysis of the memristor. Different researchers have come up with their model to improve the existing ones. These models can be linear, nonlinear or exponential. To overcome the boundary problem, many window functions have been proposed. Different models have their explanations of voltage-current relationship and state variable derivatives. This paper presents a detailed review and a comparative study of the existing memristor models based on their I-V characteristic curve. Original experimental I–V curve from the HP lab has been used as the reference for comparison.  相似文献   
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