The electromagnetic interference (EMI) shielding mechanism of carbon nanotube (CNT)/polymer nanocomposites synthesized through a unique processing technique has been studied. As CNT/polymer nanocomposites evolve towards device applications, homogenous dispersion of CNTs has become a main objective to realize their full potential. In this work, dispersion of multi‐walled carbon nanotubes (MWCNTs) in polystyrene (PS) powder via dry state tumble mixing has been carried out. This involves the coating of the PS particles with the MWCNTs. Pellets were prepared by hot compression of resulted mixture. Conductivity behavior has shown that an extremely small mass fraction of 0.05 wt % MWCNTs in PS is good enough for percolation threshold. A detailed study of EMI shielding behavior of these composites is reported in addition to physical phenomena involved. The shielding effectiveness achieved is higher compared to solution mixing technique used by others. Decrease in hardness with increase in MWCNT content is little. Scanning electron microscope studies of these nanocomposites revealed a web/mesh like structure consisting of MWCNTs. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40201.

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Nanocomposites of well-dispersed multi walled carbon nanotubes (MWCNTs) in an acrylonitrilebutadiene-styrene (ABS) matrix were prepared by dry tumble mixing and a subsequent hot compression technique. The preparation method is analysed here to assist in the explanation and understanding of the experimental observations. The vision of the processing method has been confirmed using scanning electron microscopy. As a result of decent dispersion and pre-localization of MWCNTs in the ABS matrix, the electrical conductivity of the nanocomposite as a function of filler content exhibits a distinctive percolation behavior with a percolation threshold of only 0.0005 volume fraction. The high aspect ratio of MWCNTs enables the creation of interconnected networks within the ABS matrix at a very low nanofiller loading, while their high inherent electrical conductivity yields nanocomposites with a high bulk electrical conductivity. To explain the conductivity behaviour, statistical percolation theory and GEM theory are employed. The model parameters elaborated show that both models can adequately describe the behaviour. A comparative analysis of the applicability of percolation theory and GEM theory for expressing the conductivity behavior of the MWCNT/ABS composites with other research works has been performed. Finally, the electrical conductivity of MWCNTs based on the data in this work and elsewhere is evaluated. The universal exponent t is found to be 1.93 for a best-fit value of percolation threshold of 0.00048 5 vol. fraction of MWCNTs in this work. The D shore hardness results have revealed a random increase in hardness and density with an increasing MWCNT content.

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Recently, the electronic heath record (EHR) has become the chosen method to maintain a patient's health information. The advancement of cloud computing enables users to access their data with flexibility, providing large storage capability at low costs, which encourages EHR maintainers to consider shifting from their own storage to the cloud. In cloud computing, it is no doubt that securing EHRs poses a gigantic challenge. Various security properties like access control, data privacy, and scalable access between different clouds needs to be satisfied. This article presents a secure and efficient blueprint for securing data confidentiality on cloud computing storage. The proposed framework is carried out for EHR confidential data on cloud storage. Moreover, the proposed approach combines the obfuscation and RSA encryption together to enforce confidentiality and authentication. Through this framework, the data confidentiality and authentication scheme on EHR information can be enforced on clouds storage.

Biodiversity of insect pollinators on fennel cv. , was studied in Hisar, Haryana, India. Twenty-five insect species belonging to fifteen families of five orders were recorded from fennel flowers, in which, seven belong to order Lepidoptera, nine to Hymenoptera, five to Diptera, three to Coleoptera and one to Odonata. Among the insect pollinators, Apis florea F., A. cerana indica F., A. mellifera L. and A. dorsata F. were the most frequent visitors. Among different bee species, the maximum mean population observed in case of A. florea (13845052) and A. cerana (5586381). Hence, it was observed that A. dorsata was the most efficient pollinator followed by A. florea, A. mellifera and A. cerana on fennel cv. HF-143 flowers under agro ecological conditions of Hisar (Haryana). Hence, insect pollinators were essential to get good returns in this seed crop. The activity of different bee species on fennel varied with different abiotic factors and had significantly positive correlation with bright sun shine hours (BSS) and temperature (TEMP) in different hours of the day during foraging but had negative correlation with relative humidity (RH). It was observed that the effect of wind velocity on foraging of different bee species was not significant. Thus, the impact of abiotic environmental factors may decide the foraging activity of different insect pollinators.

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Purpose. Sonography has been used to evaluate children with dengue hemorrhagic fever, but to our knowledge no such studies have been conducted with adults. We present the sonographic findings in 40 adults with severe (grade III) dengue hemorrhagic fever (DHF).Methods. Forty patients (30 men and 10 women, aged 16-65 years) given a presumptive diagnosis of grade III dengue hemorrhagic fever during a documented regional epidemic underwent abdominal sonography. Ten also underwent chest radiography. Serologic confirmation was obtained in 5 patients, and in the rest the diagnosis was based on epidemiologic and clinical findings.Results. Sonographic findings included pleural effusion in 21 patients (53%), thickening of the gallbladder wall in 17 (43%), and mild ascites in 6 (15%). These findings were similar to those of previous studies of severe DHF in children, although the incidence of pleural effusion and ascites was slightly lower in our series. Neither pleural effusion nor ascites was apparent on clinical examination. Of the 10 patients who underwent both sonography and chest radiography, sonography detected pleural effusion in all 10, whereas radiography detected it in only 3.Conclusions. Sonographic findings in DHF in adults (pleural effusions, ascites, and gallbladder wall thickening) were similar to those described for children but seem to be of lesser severity. Abdominal sonography is a useful diagnostic tool for confirming suspected cases of DHF. Sonography was found to be superior to chest radiography in detecting pleural effusions in the 10 patients in whom radiographs were available.