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11.
Deepti Mishra Ruma Arora Swati Lahiri Sudhir Sitaram Amritphale Navin Chandra 《Protection of Metals and Physical Chemistry of Surfaces》2014,50(5):628-631
In the present work iron oxide nanoparticles have been synthesized by alkaline solvo thermal method using anhydrous ferric chloride, sodium hydroxide, polyethylene glycol and cetyl trimethyl ammonium bromide and characterized by X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM), Energy-dispersive X-ray Spectroscopy (EDX) and Thermal Gravimetric Analysis (TGA). XRD indicated that the product is a mixture of different phases of iron oxide viz. gamma-Fe2O3 (maghemite, tetragonal), Fe2O3 (maghemite, cubic), Fe3O4 (magnetite, cubic) and ?-Fe2O3(epsilon iron oxide). FESEM studies indicated that size of the particles is observed in the range of about 19.8 nm to 48 nm. EDX spectral analysis reveals the presence of carbon, oxygen, iron in the synthesized nanoparticles. The FTIR spectra indicated absorption bands due to O-H stretching, C-O bending, N-H stretching and bending, C-H stretching and Fe-O stretching vibrations. TGA curve represented weight loss of around 3.0446 % in the sample at temperature of about 180°C due to the elimination of the water molecules absorbed by the nanoparticles from the atmosphere. 相似文献
12.
Fuzzy classification has become of great interest because of its ability to utilize simple linguistically interpretable rules and has overcome the limitations of symbolic or crisp rule based classifiers. This paper introduces an extension to fuzzy classifier: a neutrosophic classifier, which would utilize neutrosophic logic for its working. Neutrosophic logic is a generalized logic that is capable of effectively handling indeterminacy, stochasticity acquisition errors that fuzzy logic cannot handle. The proposed neutrosophic classifier employs neutrosophic logic for its working and is an extension of commonly used fuzzy classifier. It is compared with the commonly used fuzzy classifiers on the following parameters: nature of membership functions, number of rules and indeterminacy in the results generated. It is proved in the paper that extended fuzzy classifier: neutrosophic classifier; optimizes the said parameters in comparison to the fuzzy counterpart. Finally the paper is concluded with justifying that neutrosophic logic though in its nascent stage still holds the potential to be experimented for further exploration in different domains. 相似文献
13.
Human detection is a central problem in development of any surveillance application. In this study, we present a simple and efficient, multi-resolution gray scale invariant approach for multiple human detection. The multiresolution is important for objects of different size and gray scale invariance is important due to uneven illumination and within-class variability. The proposed method is based on integration of central moments upon multi-resolution gray scale invariant local binary patterns operator. Since, the local binary patterns operator is invariant against different resolutions of space scale and monotonic change in gray scale, therefore the proposed method is robust in terms of variations in space scale as well as gray scale. Another advantage is high computational accuracy of the method due to use of moment operator which enhances the efficiency of the proposed method. Moreover, the proposed method is simple, as these operations can be performed within a few steps in a small neighborhood and a lookup table. The proposed method is tested on multiple human images and experimentally found appropriate for multiple human detection. The proposed method has been evaluated over two datasets, one is our own created dataset and the other is standard INRIA human detection dataset. Experimental results obtained from the proposed method demonstrate that better discrimination can be achieved for human and non-human objects in real scenes. 相似文献
14.
Surface ultrastructures of gill filaments and secondary lamellae of Rita rita and Cirrhinus mrigala, inhabiting different ecological habitat, were investigated to unravel adaptive modifications. R. rita is a sluggish, bottom dwelling carnivorous catfish, which inhabits regions of river with accumulations of dirty water. It retains its viability for long time if taken out of water. C. mrigala is an active bottom dwelling Indian major carp, which lives in relatively clean water and dies shortly after taken out of water. In R. rita, gill septa between gill filaments are reduced. Microridges on epithelial cells covering gill filaments are often continuous and arranged concentrically. Secondary lamellae are extensive. The epithelium appears corrugated, show irregular elevations and shallow depressions, and microridges on epithelial cells appear fragmented. In C. mrigala, in contrast, the gill septa are extensive. Microridges on epithelial cells covering gill filaments are fragmented. Secondary lamellae are less extensive. The epithelium appears smooth and microridges on epithelial cells are relatively inconspicuous. These differences have been considered adaptive modification in relation to habit and ecological niches inhabited by two fish species. Presence of mucous goblet cells on gill filaments is discussed in relation to their functions including precipitation of the sediments and preventing clogging of gill filaments. Infrequent mucous goblet cells in the epithelium of secondary lamellae in two fish species are considered an adaptation, minimizing thickness of the epithelium to reduce barrier between blood and water for favoring gasses exchange with increased efficiency. 相似文献
15.
Swati Ghosh Vishav Preet Singh Rana Vivekanand Kain Vivek Mittal S.K. Baveja 《Materials & Design》2011,32(7):3823-3831
Effect of residual stress generated during tube fabrication, roll expansion and machining of stainless steel on the stress corrosion cracking (SCC) susceptibility was studied by testing fabricated tubes, tube–tube sheet joint and heavily machined plate of austenitic stainless steel (SS) in boiling MgCl2. U bend samples of machined plate were exposed to acidified SO4 + Cl? environment at room temperature to study its ambient temperature SCC behavior. The results correlate the SCC behavior of the SS tubes and roll expanded joints to the nature and magnitude of residual stresses present. The study also highlights the distinct difference in ambient temperature SCC behavior of machined vs. nonmachined surfaces. 相似文献
16.
Swati Mohan Rajiv Prakash 《Materials science & engineering. C, Materials for biological applications》2010,30(5):781-787
We report for the first time the functionalization of a conducting polymer with a metal complex in order to develop a new type of catalytic material exhibiting better electronic communication through their delocalized π electrons. The Co(II) complex having hydroxyl group as functional moiety is chemically coupled with carboxyl group of polyanthranilic acid which itself is a self doped conducting polymer. The covalent linkage between Co(II) and –OH group is confirmed using UV–vis, FT-IR and NMR spectroscopic techniques. The Co(II) complex functionalized polymer does exhibit excellent redox behavior and stability with mixed properties of Co(II) complex and π-conjugated polymer. The material possesses potential benefits in sensors/biosensor applications and it is demonstrated for the electroanalysis of ascorbic acid at a level of nano molar concentration. 相似文献
17.
Mehta Swati; Orenczuk Steven; Hansen Kevin T.; Aubut Jo-Anne L.; Hitzig Sander L.; Legassic Matthew; Teasell Robert W. 《Canadian Metallurgical Quarterly》2011,56(1):15
Study Design: Systematic review. Objective: To examine the evidence supporting the effectiveness of cognitive behavioral therapy (CBT) for improving psychosocial outcomes in individuals with spinal cord injury (SCI). Method: Electronic databases (MEDLINE, CINAHL, EMBASE, and PsycINFO) were searched for studies published between 1990 and October 2010. Randomized control trials (RCTs) and nonrandomized control trials (non-RCTs) utilizing a CBT intervention to improve psychosocial outcomes (depressive symptomatology, anxiety, coping, and adjustment to disability) in outpatient persons with SCI were included for review. Levels of evidence were assigned to each study using a modified Sackett scale. Effect size calculations for the interventions were provided where possible. Results: Nine studies met the inclusion criteria. The studies reviewed included two RCTs, six prospective controlled trials (PCTs) and one cohort study. All studies examined at least two groups. There is Level 1 and Level 2 evidence supporting the use of specialized CBT protocols in persons with SCI for improving outcomes related to depression, anxiety, adjustment, and coping. Conclusions: CBT holds promise as an effective approach for persons with SCI experiencing depression, anxiety, adjustment, and coping problems. As CBT may involve many different components, it is important in the future to determine which of these elements alone or in combination is most effective in treating the emotional consequences of SCI. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
18.
Manoj Mundada Bahadur Singh Swati Maske 《International Journal of Food Science & Technology》2010,45(8):1732-1738
For the optimisation of osmotic dehydration by response surface methodology, the experiments were conducted according to Central Composite Rotatable Design (CCRD) with three variables at five levels. The low and high levels of the variables were 40 and 50 °C for osmotic solution temperature, 45 and 55°Bx for sucrose solution concentration, 60 and 100 min for duration of dipping in osmotic solution, respectively. The fruit to solution ratio was kept 1:4 (w/w) during all the experiments. Before dipping the arils in sucrose solution, the freezing of the whole pomegranate at ?18 °C was carried out to increase the permeability of the outer cellular layer of the arils. The arils were further convectively dehydrated at 60 °C air temperature up to final moisture content of 10% (wb) to make it a shelf stable product. The optimum conditions for osmotic solution concentration, temperature and process duration were 55°Bx, 40 °C and 100 min, respectively. 相似文献
19.
Mixed phase (rutile/anatase) TiO2 nanorods have been synthesized using an anionic surfactant template. Nanorod synthesis has been achieved using mild reaction conditions and without using any rod-shaped template. The shape and crystallinity of the TiO2 nanomaterials can be modulated by careful control of the surfactant concentration. The novelty of the present work is that the anatase/rutile mixed phase nanorods were formed without using the well-known layer by layer assembly method or the hydrothermal method. These mixed phase TiO2 nanorods are highly luminescent, can be easily sensitized by fluorescent dyes, show significant dye adsorption ability and function as efficient photocatalysts. 相似文献
20.
Swati Roy Maitra K. S. Reddy L. S. Ramachandra 《International Journal of Fracture》2014,189(2):181-193
In concrete pavements, fatigue is one of the major causes of distress. Repeated loads result in the formation of cracks. The propagation of these cracks cause internal progressive damage within the structure, which ultimately leads to failure of the pavement due to fatigue. This paper presents a theoretical investigation of crack propagation within concrete pavement and its fatigue characteristics under cyclic loading. A numerical fatigue performance model has been developed for this purpose. The model is based on fictitious crack approach for the propagation of cracks and stress degradation approach for estimating the bridging stress under cyclic loading. Using the numerical model, a parametric study has been performed for a typical concrete pavement to evaluate its fatigue characteristics for different foundation strengths. The method can be used for prediction of crack propagation in concrete pavement under cyclic loading and gives an estimate of the incremental damage or the entire crack history of the pavement. 相似文献