49,561 research outputs found
Effect of Vinyl and Silicon Monomers on Mechanical and Degradation Properties of Bio-Degradable Jute-Biopol® Composite
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Composites of jute fabrics (Hessian cloth) and Biopol® were prepared by compression molding process. Three types of Biopol® (3-hydroxbutyrate-co-3-hydroxyvalarate) such as D300G, D400G and D600G, depending on the concentration of 3-hydroxyvalarate (3HV) in 3-hydroxbutyrate (3HB) were taken for this purpose. Mechanical properties such as tensile strength (TS), bending strength (BS), elongation at break (Eb) and impact strength (IS) of the jute-Biopol® composites were studied. It was found that the composite with D400G produced higher mechanical properties in comparison to the other two types of Biopol®. To increase mechanical properties as well as interfacial adhesion between fiber and matrix, 2-ethyl hydroxy acrylate (EHA), vinyl tri-methoxy silane (VMS) and 3-methacryloxypropyl tri-methoxy silane (MPS) were taken as coupling agents. Enhanced mechanical properties of the composites were obtained by using these coupling agents. Biopol® D400G composites showed the highest mechanical properties. Among the coupling agents EHA depicts the highest increase of mechanical properties such as tensile strength (80%), bending strength (81%), elongation at break (33%) and impact strength (130%) compared pure Biopol. SEM investigations demonstrate that the coupling agents improve the interfacial adhesion between fiber and matrix. The surface of the silanized jute was characterized by FTIR and found the deposition of silane on jute fiber was observed. Soil degradation test proved that the composite prepared with EHA treated jute exhibits better degradation properties in comparison to pure Biopol®
Higher Dimensional Inhomogeneous Perfect Fluid Collapse in \emph{f(R)} Gravity
This paper is about the -dimensional gravitational contraction of
inhomogeneous fluid without heat flux in the framework of metric theory
of gravity. Matching conditions for two regions of a star has been derived by
using the Darmois junction conditions. For the analytic solution of equations
of motion in modified theory of gravity, we have taken scalar curvature
as constant. Hence final result of gravitational collapse in this frame work is
the existence of black hole and cosmological horizons, both of these form
earlier than singularity. It has been shown that constant curvature term
( is constant scalar curvature) slows down the collapsing
process.Comment: 17 Pages, to appear in European Physical Journal
A review of the perturbation theory as applied to the determination of geopotential
Satellite theory to determine geopotential from orbital motion of artificial earth satellite
Stabilization of a Two-Coordinate [GeCl]<sup>+</sup> Cation by Simultaneous σ and π Donation from a Monodentate Carbodiphosphorane
Give me four: The synthesis, structure, and reactivity of [GeCl]+ and [SnCl]+ cations bearing a carbodiphosphorane as ancillary ligand are presented. In the Ge compound, simultaneous σ and π donation from the carbodiphosphorane to Ge is observed (see HOMO (left) and HOMO−1 (right); C black, H white, P orange, Cl green, Ge purple (not visible)), whereas only the σ dative component is present in the Sn analogue
Paradoxical signaling regulates structural plasticity in dendritic spines
Transient spine enlargement (3-5 min timescale) is an important event
associated with the structural plasticity of dendritic spines. Many of the
molecular mechanisms associated with transient spine enlargement have been
identified experimentally. Here, we use a systems biology approach to construct
a mathematical model of biochemical signaling and actin-mediated transient
spine expansion in response to calcium-influx due to NMDA receptor activation.
We have identified that a key feature of this signaling network is the
paradoxical signaling loop. Paradoxical components act bifunctionally in
signaling networks and their role is to control both the activation and
inhibition of a desired response function (protein activity or spine volume).
Using ordinary differential equation (ODE)-based modeling, we show that the
dynamics of different regulators of transient spine expansion including CaMKII,
RhoA, and Cdc42 and the spine volume can be described using paradoxical
signaling loops. Our model is able to capture the experimentally observed
dynamics of transient spine volume. Furthermore, we show that actin remodeling
events provide a robustness to spine volume dynamics. We also generate
experimentally testable predictions about the role of different components and
parameters of the network on spine dynamics
Temperature and finite-size effects in collective modes of superfluid Fermi gases
We study the effects of superfluidity on the monopole and quadrupole
collective excitations of a dilute ultra-cold Fermi gas with an attractive
interatomic interaction. The system is treated fully microscopically within the
Bogoliubov-de Gennes and quasiparticle random-phase approximation methods. The
dependence on the temperature and on the trap frequency is analyzed and
systematic comparisons with the corresponding hydrodynamic predictions are
presented in order to study the limits of validity of the semiclassical
approach.Comment: 9 pages, 4 figure
The Nambu-Jona-Lasinio model with staggered fermions
We investigate the neighbourhood of the chiral phase transition in a lattice
Nambu--Jona-Lasinio model, using both Monte Carlo methods and lattice
Schwinger-Dyson equations.Comment: Talks at LAT93, Dallas, U.S.A. Postscript file, 6 pages, figures
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Fault-Tolerant Secure Data Aggregation Schemes in Smart Grids: Techniques, Design Challenges, and Future Trends
Secure data aggregation is an important process that enables a smart meter to perform efficiently and accurately. However, the fault tolerance and privacy of the user data are the most serious concerns in this process. While the security issues of Smart Grids are extensively studied, these two issues have been ignored so far. Therefore, in this paper, we present a comprehensive survey of fault-tolerant and differential privacy schemes for the Smart Gird. We selected papers from 2010 to 2021 and studied the schemes that are specifically related to fault tolerance and differential privacy. We divided all existing schemes based on the security properties, performance evaluation, and security attacks. We provide a comparative analysis for each scheme based on the cryptographic approach used. One of the drawbacks of existing surveys on the Smart Grid is that they have not discussed fault tolerance and differential privacy as a major area and consider them only as a part of privacy preservation schemes. On the basis of our work, we identified further research areas that can be explored
Decays of mesons with charm quarks on the lattice
We investigate mesons containing charm quarks on fine lattices with a^{-1}
\sim 5 GeV. The quenched approximation is employed using the Wilson gauge
action at \beta = 6.6 and nonperturbatively O(a) improved Wilson quarks. We
present results for decay constants using various interpolating fields and give
preliminary results for form factors of semileptonic decays of D_s mesons to
light pseudoscalar mesons.Comment: 7 pages, 3 figures, talk presented at the XXV International Symposium
on Lattice Field Theory, 30 July - 4 August 2007, Regensburg, German
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