Search results for "sol"
showing 10 items of 23782 documents
Synthesis, Characterization of FexZr1-xO2Solid Solution Nanoparticles and Bulk Powders Prepared Using a Sol-Gel Technique
2015
Parallel Genetic Solution for Multiobjective MDO
1997
Publisher Summary This chapter reviews a multiobjective, multidisciplinary design optimization of two-dimensional airfoil designs. The control points on leading and trailing edges remain fixed, and the y-coordinates of the other control points are allowed to change during the optimization process. The grid for the Euler solver depends continuously and smoothly on the design parameters. The number of nodes and elements in the mesh might vary according to design because the meshes for the Helmholtz solver are done using the local fitting. The computations are made on an IBM SP2 parallel computer using high-performance switch and the MPICH message-passing library. As gradients are not required…
Spin-lattice relaxation of deuterated methyl groups: Implications of the pauli principle
1999
The high-field spin-lattice relaxation of deuterated methyl groups undergoing rotational tunneling is investigated theoretically. It is found that for systems showing a tunneling frequency comparable to accessible Larmor frequencies the relaxation to equilibrium of the Zeeman energy does not follow a simple exponential time dependence even in powdered samples due to a finite coupling to the relaxation of the tunneling system. This finding contrasts to the high-temperature behavior of reorienting methyl groups which undergo simple exponential relaxation. The nonexponentiality has its origin in the statistical coupling of the three deuteron spins due to the Pauli principle.
New Types of Jacobian-Free Approximate Riemann Solvers for Hyperbolic Systems
2017
We present recent advances in PVM (Polynomial Viscosity Matrix) methods based on internal approximations to the absolute value function. These solvers only require a bound on the maximum wave speed, so no spectral decomposition is needed. Moreover, they can be written in Jacobian-free form, in which only evaluations of the physical flux are used. This is particularly interesting when considering systems with complex Jacobians, as the relativistic magnetohydrodynamics (RMHD) equations. The proposed solvers have also been extended to the case of approximate DOT (Dumbser-Osher-Toro) methods, which can be regarded as simple and efficient approximations to the classical Osher-Solomon method. Som…
Polaroid-Type Operators
2018
In this chapter we introduce the classes of polaroid-type operators, i.e., those operators T ∈ L(X) for which the isolated points of the spectrum σ(T) are poles of the resolvent, or the isolated points of the approximate point spectrum σap(T) are left poles of the resolvent. We also consider the class of all hereditarily polaroid operators, i.e., those operators T ∈ L(X) for which all the restrictions to closed invariant subspaces are polaroid. The class of polaroid operators, as well as the class of hereditarily polaroid operators, is very large. We shall see that every generalized scalar operator is hereditarily polaroid, and this implies that many classes of operators acting on Hilbert s…
Quenched and annealed free energies
1984
This paper gives a simple exposition of the Nishimori method to solve certain quenched, random bond spin-glass models. It allows a transparent physical interpretation in terms of annealed systems. As an application a special solution of the Sherrington-Kirkpatrick model with a discrete probability distribution is obtained and shown to agree with the solution for the Gaussian case. This substantiates the claim that the averaged free energy does not depend on the details of the probability distribution Expose simple de la methode de Nishimori pour resoudre certains modeles de verres de spin avec interactions aleatoires. Interpretation transparente en termes de systemes recuits. Presentation d…
Errors Generated by Uncertain Data
2014
In this chapter, we study effects caused by incompletely known data. In practice, the data are never known exactly, therefore the results generated by a mathematical model also have a limited accuracy. Then, the whole subject of error analysis should be treated in a different manner, and accuracy of numerical solutions should be considered within a framework of a more complicated scheme, which includes such notions as maximal and minimal distances to the solution set and its radius.
Legally protected cultural goods and bankruptcy proceedings
2020
Artykuł dotyczy ogólnych problemów prawnych związanych z celami prawny-mi postępowania upadłościowego w związku z celami ochrony dziedzictwa kulturowego. Obydwa zagadnieniami zbudowane są przez zupełnie inne systemy wartości. Postępowa-nie upadłościowe ma na celu ochronę interesów majątkowych ograniczonej grupy ludzi, podczas gdy dziedzictwo kulturowe jest chronione dla obecnych i przyszłych pokoleń, bez względu na jego znaczenie handlowe. Niewypłacalność właściciela dóbr kultury jest pro-blemem globalnym, ale krajowe przepisy dotyczące upadłości i przepisy dotyczące ochrony dziedzictwa kulturowego różnią się bardzo poważnie. Z tego powodu artykuł nie ogranicza się do żadnego konkretnego po…
Towards Controlled Synthesis of Water-Soluble Gold Nanoclusters : Synthesis and Analysis
2019
Water-soluble gold nanoclusters with well-defined molecular structures and stability possess particular biophysical properties making them excellent candidates for biological applications as well as for fundamental spectroscopic studies. The currently existing synthetic protocols for atomically monodisperse thiolate-protected gold nanoclusters (AuMPCs) have been widely expanded with organothiolates, yet the direct synthesis reports for water-soluble AuMPCs are still deficient. Here, we demonstrate a wet-chemistry pH-controlled synthesis of two large water-soluble nanoclusters utilizing p-mercaptobenzoic acid (pMBA), affording different sizes of plasmonic AuMPCs on the preparative scale (∼7 …
A route to simple nonionic surfactants
2016
AbstractA method for the synthesis of nonionic surfactants – N-alkyl-O-(2-hydroxyethyl) carbamates is proposed by acylation of fatty amines with ethylene carbonate without any solvent or catalyst. The surface tension of the prepared surfactants was measured, toxicity and biodegradability were determined for the surfactant with n-dodecyl as a hydrophobic group and N-monosubstituted amide and hydroxyl groups for their hydrophilic part.