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1.
The viscoelastic response of plasticized PVC was determined from stress-relaxation data over a wide range of time at different temperatures. The relaxation modulus as a function of time was determined from these data. The relaxation curves were then shifted horizontally to obtain a master curve at a reference temperature. The amount of shift was evaluated using the WLF equation. The coefficients C and C used in the equation for the PVC were determined according to the method of reduced variables. 相似文献
2.
Sujoy Basu Lauro Beltrão Costa Francisco Brasileiro Sujata Banerjee Puneet Sharma Sung-Ju Lee 《Peer-to-Peer Networking and Applications》2009,2(4):348-366
Large scale grid computing systems may provide multitudinous services, from different providers, whose quality of service
will vary. Moreover, services are deployed and undeployed in the grid with no central coordination. Thus, to find out the
most suitable service to fulfill their needs, or to find the most suitable set of resources on which to deploy their services,
grid users must resort to a Grid Information Service (GIS). This service allows users to submit rich queries that are normally
composed of multiple attributes and range operations. The ability to efficiently execute complex searches in a scalable and
reliable way is a key challenge for current GIS designs. Scalability issues are normally dealt with by using peer-to-peer
technologies. However, the more reliable peer-to-peer approaches do not cater for rich queries in a natural way. On the other
hand, approaches that can easily support these rich queries are less robust in the presence of failures. In this paper we
present the design of NodeWiz, a GIS that allows multi-attribute range queries to be performed efficiently in a distributed
manner, while maintaining load balance and resilience to failures. 相似文献
3.
4.
Tanvi Bhasin Ashish Agarwal Sujata Sanghi R.K. Kotnala Jyoti Shah Manisha Yadav Muskaan Tuteja 《Ceramics International》2018,44(7):7629-7636
Multiferroic composites of spinel ferrite and ferroelectric xCoFe2O4 – (1-x)Na0.5Bi0.5TiO3 (with x = 0.10,0.30,0.50) were efficiently prepared by standard solid state reaction mechanism. X-ray diffractometer was used to analyze crystal structure of the prepared composites. The observed XRD patterns of the composites comprise peaks of both the phases i.e. ferrite and ferroelectric, with no sign of secondary peaks. Rietveld refinement of XRD data further confirms the coexistence of these two phases with cubic (Fd3m) and rhombohedral (R3c) symmetry corresponding to ferrite and ferroelectric phase respectively. The 3-dimensional overview of crystal structure of pure CoFe2O4 and Na0.5Bi0.5TiO3 and of composite 0.50CoFe2O4?0.50Na0.5Bi0.5TiO3 is generated by using refined parameters. The dielectric constant (ε´) and dielectric loss (tanδ) values were recorded as a function of frequency ranging from 100?Hz to 7?MHz and at different temperatures. Both ε´ and tanδ follow dispersion pattern at lower frequencies while show frequency independent behavior at higher frequencies. The magnetic evaluation carried by analyzing M-H hysteresis loop reveals the ferrimagnetic characteristics of these composites. The highest value of magnetic moment is 1.12μB observed for composite 0.50CoFe2O4 – 0.50Na0.5Bi0.5TiO3. Magnetoelectric (ME) voltage coefficient (α) was also demonstrated to observe the interaction between ferrite and ferroelectric phases. The highest value of α (72.72μV/Oe cm) is obtained for low ferrite composition 0.10CoFe2O4 – 0.90Na0.5Bi0.5TiO3, which suggests the dependence of magnetoelectric response on the resistivity of the composites. 相似文献
5.
Maniyan CG Mohan G Pillai PM Sujata R Haridasan PP Khan AH 《Radiation protection dosimetry》2003,104(1):71-76
Potassium (K) content in 408 male workers of a rare earths processing plant was estimated using a shadow shield whole body counter. The average K content in the non-vegetarian and vegetarian group was found to be 1.5 g kg(-1) and 2.1 g kg(-1) respectively. The absorbed dose due to 40K is determined as 0.18 +/- 0.02 mGy. While the K content was found to be proportional to body build index, it is inversely proportional to slenderness. Body K was maximum in the middle aged group (35-45 y) and a minimum in younger and older persons. The correlation of potassium content with some disease patterns was also studied. Diabetes mellitus patients were observed to have low K content of 0.9 +/- 0.2 g kg(-1) and those who suffer from cardiovascular disorders were found to have high K content 2.7 +/- 0.3 g kg(-1). The studies showed that the depletion of body K content takes place a few years prior to the clinical detection of diabetes and it builds up a few years before the clinical detection of cardiovascular disorders. It is stressed that the medical information is preliminary as the number of subjects studied was not very large. Wider and in depth study by various groups can hopefully strengthen the observation. 相似文献
6.
The butyl acrylate (BA)/methyl methacrylate (MMA), and glycidyl methacrylate (GMA) composite copolymer latex was synthesized by seeded emulsion polymerization technique taking poly(methyl methacrylate) (PMMA) latex as the seed. Four series of experiments were carried out by varying the ratio of BA : MMA (w/w) (i.e. 3.1 : 1, 2.3 : 1, 1.8 : 1, and 1.5 : 1) and in each series GMA content was varied from 1 to 5% (w/w). The structural properties of the copolymer were analyzed by FTIR, 1H‐, and 13C‐NMR. Morphological characterization was carried out using transmission electron microscopy (TEM). In all the experiments, monomer conversion was ~99% and final copolymer composition was similar to that of feed composition. The incorporation of GMA into the copolymer chain was confirmed by 13C‐NMR. The glass transition temperature (Tg) of the copolymer latex obtained from the differential scanning calorimetry (DSC) curve was comparable to the values calculated theoretically. With increase in GMA content, particles having core‐shell morphology were obtained, and there was a decrease in the particle size as we go from 2–5% (w/w) of GMA. The adhesive strength of the latexes was found to be dependent on the monomer composition. With increase in BA : MMA ratio, the tackiness of the film increased while with its decrease the hardness of the film increased. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
7.
Prashant Singh Pradeep Kumar Anju Katyal Rashmi Kalra Sujata K. Dass Satya Prakash Ramesh Chandra 《Catalysis Letters》2010,134(3-4):303-308
In this present work, we report that phosphotungstic acid provides a simple, efficient and environmentally benign route is a two-component one-pot domino Knoevenagel-type condensation/Michael reaction between 4-coumarin derivative and an aldehyde in water as a solvent in shorter duration with high yields. 相似文献
8.
Anindita Bhadra Aniruddha Mitra Sujata A. Deshpande Kannepalli Chandrasekhar Dattatraya G. Naik Abraham Hefetz Raghavendra Gadagkar 《Journal of chemical ecology》2010,36(4):424-431
Queens and workers are not morphologically differentiated in the primitively eusocial wasp, Ropalidia marginata. Upon removal of the queen, one of the workers becomes extremely aggressive, but immediately drops her aggression if the
queen is returned. If the queen is not returned, this hyper-aggressive individual, the potential queen (PQ), will develop
her ovaries, lose her hyper-aggression, and become the next colony queen. Because of the non-aggressive nature of the queen,
and because the PQ loses her aggression by the time she starts laying eggs, we hypothesized that regulation of worker reproduction
in R. marginata is mediated by pheromones rather than by physical aggression. Based on the immediate loss of aggression by the PQ upon return
of the queen, we developed a bioassay to test whether the queen’s Dufour’s gland is, at least, one of the sources of the queen
pheromone. Macerates of the queen’s Dufour’s gland, but not that of the worker’s Dufour’s gland, mimic the queen in making
the PQ decrease her aggression. We also correctly distinguished queens and workers of R. marginata nests by a discriminant function analysis based on the chemical composition of their respective Dufour’s glands. 相似文献
9.
The filterbank transceiver structure for fractal modulation has been developed. It has been shown that the transceiver complexity
is comparable to that of OFDM.The use of orthogonal space time block codes (OSTBC) in conjunction with Fractal Modulation
(STFrM) in the presence of frequency selective fading channels has also been considered. An L scale fractal modulation and coherent demodulation effectively converts a frequency selective channel into L flat fading channels per information symbol with random scale gains. The analysis of the proposed scheme in terms of bit
error rate has been performed. A diversity order of m
T
m
R
L can be achieved, where m
T
,m
R
are the number of transmitters and receivers, respectively. This increase in diversity order in comparison with that achieved
for the OFDM case is at a cost of lower spectral efficiency. However the spectral efficiency of STFrM can be improved R times by the use of multiplicity ‘R’ multiwavelets. 相似文献
10.
Sudipta BISWAS Satadru PRAMANIK Suman MANDAL Sudeshna SARKAR Sujata CHAUDHURI Swati DE 《材料科学前沿(英文版)》2020,14(1):24
Asymmetric patchy Ag/Cu Janus nanoparticles (NPs) were synthesized via a “seed-mediated” approach. This is the first report of synthesis of nanometer sized metal-based Janus NPs without using complicated methods. Selective adsorption of the surfactant onto the seed NPs leads to the formation of Janus type structure. Subsequently the reduction potential of Ag+/Ag0 and Cu2+/Cu0 systems directs the formation of the “patch”. The patchy Janus NPs show significant antifungal activity towards a potent rice pathogen thus offering the prospect of future application in crop protection. 相似文献