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排序方式: 共有315条查询结果,搜索用时 46 毫秒
1.
R. V. Iyer K. Sooryanarayana T. N. Guru Row K. Vijayan 《Journal of Materials Science》2003,38(1):133-139
Using X-ray diffraction data, the behaviour of Kevlar 49 fibres at low temperatures, up to –100°C, has been analysed. During cooling, the basal plane of the monoclinic unit cell shrinks whereas the c- (unique, chain axis) length is not significantly affected. In contrast, in the return heating cycle to ambient temperature, the basal plane expands and contraction occurs along the chain direction. The unit cell registers a reduction in volume in both the cooling and heating cycles. Conspicuously, after a cycle of cooling and heating, the unit cell does not return to its initial volume. 相似文献
2.
Nibedita Mitra Kalyani Vijayan B. N. Pramila Bai S. K. Biswas 《Journal of the American Ceramic Society》1993,76(2):533-535
Cutting of Y2 O3 -doped TZP rods by a low-speed diamond saw introduces an unidentified, metastable phase X (x -ZrO2 ) coexisting with the tetragonal ( t -ZrO2 ) and the monoclinic ( m -ZrO2 ) phases initially present in the sample. Further mechanical deformation of the cut surface by indentation or polishing sustains the x -ZrO2 . Chemical etching removes the x -ZrO2 and increases the m -ZrO2 content. 相似文献
3.
Archit Rathore Nithin Chalapathi Sourabh Palande Bei Wang 《Computer Graphics Forum》2021,40(1):382-397
Deep neural networks such as GoogLeNet, ResNet, and BERT have achieved impressive performance in tasks such as image and text classification. To understand how such performance is achieved, we probe a trained deep neural network by studying neuron activations, i.e.combinations of neuron firings, at various layers of the network in response to a particular input. With a large number of inputs, we aim to obtain a global view of what neurons detect by studying their activations. In particular, we develop visualizations that show the shape of the activation space, the organizational principle behind neuron activations, and the relationships of these activations within a layer. Applying tools from topological data analysis, we present TopoAct , a visual exploration system to study topological summaries of activation vectors. We present exploration scenarios using TopoAct that provide valuable insights into learned representations of neural networks. We expect TopoAct to give a topological perspective that enriches the current toolbox of neural network analysis, and to provide a basis for network architecture diagnosis and data anomaly detection. 相似文献
4.
Ontologies are currently emerging as representation techniques for overlapping compatibility context domains. The continuing need for more effective information retrieval has lead to the creation of the notions of the semantic web and personalized information management. Subsequently, the need for effective ontology visualization for design, management and browsing has arisen. Several ontology visualization tools have come out to strengthen the users’ cognitive support. The primary goal of this paper is to present a survey on recently implemented ontology visualization tools and their contributions in the enrichment of users’ cognitive support. This work also presents the preliminary results of an evaluation of three visualization tools to determine the suitability of each method for end user applications where ontologies are used as browsing aids. 相似文献
5.
Experimental measurements were made of the pH, density, bulk viscosity and electrical conductivity of aqueous solutions of sodium lauryl sulphate for a wide range of concentrations at 25°C. Also, the time-dependent interfacial tension data of this system with mutually saturated benzene phases are reported. Comparison of these data with literature values shows fair agreement in the majority of the cases and further reveals the lack of data in the earlier investigations below the critical micelle concentration of sodium lauryl sulphate in water. A detailed compilation of the data, reported in the literature since 1937, of the pH, density, bulk viscosity, electrical conductivity, surface tension, interfacial tension with benzene, surface excess concentration, surface shear viscosity, diffusivity and critical micelle concentration of the sodium lauryl sulphate system is given. The importance of this anionic surfactant system together with the various factors which influence the physical properties is examined. 相似文献
6.
Pillai S. Vijayan Santhanakrishnan T. Kumar N. Suresh Rajesh R. 《Multidimensional Systems and Signal Processing》2022,33(3):879-898
Multidimensional Systems and Signal Processing - High-performance sonar systems mostly combine a large sensor array and an efficient beamformer for enhancing the overall detection capabilities and... 相似文献
7.
Conducting polypyrrole (PPy) thin-film electrodes were prepared by the electropolymerization of pyrrole on gold-coated glass plates. Films of various roughnesses were obtained by the variation of the scan rates during electropolymerization. These thin films were modified by doping with 6mM of the dopant NiCl2. The surface morphology of the films was studied by scanning electron microscopy and atomic force microscopy (AFM), which suggested films prepared with a high scan rate were rougher in nature than the films produced with a low scan rate. The electrocatalytic reduction of nitrobenzene was carried out with these electrodes with the cyclic voltammetry technique in acetonitrile containing 0.1M HClO4 as a supporting electrolyte. The various results obtained show that the conducting PPy thin-film electrodes were catalytically active toward the electroreduction process. The modified PPy film electrodes doped with NiCl2 were more active toward nitrobenzene electroreduction than the PPy film alone. The results indicate that the roughness of the films played a very important role in determining their catalytic activity. The PPy films that were more rough in nature were catalytically more active than the smooth films; this may have been due to the availability of more reactive sites in the case of rough films. The apparent diffusion coefficients of the PPy film electrodes were also calculated. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
8.
S A Nithin Joseph Reddy E Thrinadh S Prabhakaran S Kalainathan N Arivazhagan M Manikandan 《Sadhana》2018,43(12):193
Microsegregation of alloying elements is prone to hot cracking in the weldment of alloy C-276. The formation of topologically close packed phases P and µ is largely responsible for the hot cracking. The present study articulates the effect of laser shock peening (LSP) to improve the metallurgical and mechanical properties of the weld joint. The weld joint was fabricated by pulsed current gas tungsten arc welding (PCGTAW) using an ERNiCrMo-3 filler wire. LSP without coating was carried out on the cap surface of the weldment. Microstructural studies were carried out to compare the as-welded and laser-peened microstructure on the fusion zone. The results show that a fine equiaxed dendritic structure was observed in both conditions. EDS analysis was carried out to evaluate the microsegregation of alloying elements. EDS analysis indicates that there are no secondary intermetallic phases. X-ray diffraction analysis was carried out to evaluate the phase change and crystallite size in the as-welded and laser shock peened fusion zone. The result shows 48.99% reduction in crystallite size after LSP. Hardness and tensile strength results indicate there is a consequential increase in laser shock peened specimen compared with as-welded specimen. 相似文献
9.
Hot Corrosion Behaviour of Refractory and Rare Earth Oxide Reinforced CoCrAlY APS Coatings at 700 °C
H. S. Nithin V. Desai M. R. Ramesh 《Transactions of the Indian Institute of Metals》2018,71(10):2403-2413
This paper investigates cyclic hot corrosion of plasma sprayed CoCrAlY?+?Al2O3?+?YSZ (C1) and CoCrAlY?+?CeO2 (C2) composite coatings on MDN 321 and Superni 76 substrates in molten salt (Na2SO4-60%V2O5) environment exposed to 700 °C. Weight change technique is used to evaluate the corrosion performance. Both C1 and C2 coatings showed better corrosion resistance than uncoated alloy. Both the coatings showed linear weight gain during the initial cycles and parabolic weight gain nature with subsequent hot corrosion cycles. The parabolic rate constant (Kp) of C1 and C2 coating was observed to be in the range 0.29–0.32?×?10?10 g2 cm?4 s?1 and 1.0–1.13?×?10?10 g2 cm?4 s?1 respectively. In C1 coating, the globular and continuously packed structure on the corroded surface having CoO, Cr2O3, CoCr2O4 and CoAl2O4 spinel oxides provided superior hot corrosion resistance. While in case of C2 coating, the outward growth of CeVO4 irregular crystals as a corrosion product of CeO2 and V2O5 salt deteriorated the oxide scales resulting in higher corrosion rate. 相似文献