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Abstract  

Restoring of the balance beam to its initial situation after a change of load can be effected by combination of forces of different kind. In former papers we discussed the possibility using the equation of motion of the balance to determine the mass to be measured. After the measurement the balance was restored by means of current pulses into the electromagnetic measuring system. In the present paper we discuss the application of electric pulses into an additional electrostatic system.

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Abstract  

Alpha spectroscopy was used to study the mechanism of electrostatic collection of thoron daughters from the air. The results indicate that ThA atoms are primarily collected on negatively charged surfaces. Atoms of ThB produced by decay of ThA already attached to the collecting surface are injected by recoil into the surface layers of solids and are suitable for use in radiotracer experiments.

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Abstract  

The enthalpic effect due to the interaction between α, β poly(N-hydroxyethyl)-DL-aspartamide (PHEA) and sodium dodecylsulfate (SDS) in aqueous solutions as a function of the surfactant concentration was measured by the calorimetric technique at various NaCl concentrations. A marked influence of the added electrolyte on the PHEA-SDS interaction was observed. An analysis of the experimental enthalpies allows to estimate the electrostatic and the hydrophobic contributions to the enthalpy of interaction between PHEA and SDS micelles. The results were rationalized in terms of effects due to the screening of the charges residing on PHEA and SDS micelles.

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Abstract

We describe a simple electrostatic model of hydrated ions [M(H2O)n]+ (n = 3–18, M = Li, Mg, Ca, K) which enables to calculate ion vibration frequency of the ground state. In this model the considered ion with a reduced mass vibrates in quasispherical well formed by the ion-dipole attractive potential and repulsive valence potential, these simplifications allowed to solve one dimensional Schrödinger equation, whilst the calculated ground state was considered as one of triply degenerated state of the three dimensional motion of the ion vs. hydration shell. The reduced partition function ratios were calculated from the vibration frequencies using Urey's (1947) harmonic approximation formula.

The results obtained in this way are in good agreement with those obtained by much more laborious ab initio molecular orbital methods, like SCF Hartree-Fock, DFT, MP2, etc. Moreover, we were able to extend calculations to hydrated Li and K ions surrounded with two shells of water molecules. These results are the first estimations of the upper limit of isotope fractionation in water solutions, which are 99.3‰ for Li and only 2.5‰ for K isotopes.

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The paper presents a parallel approach for the efficient solution of a simple 1D Laplace-Poisson equation problem by parallel finite element method. This problem is a case study. The non-overlapping domain decomposition method has been used to cut the problem into sub-regions or also called sub-domains, and it reduces the large mass matrix into smaller parts. The independent subdomains, and the assembling of these equation systems can be handled by the independent processors of a supercomputer, i.e. in a parallel way. The results of parallel finite element method have been compared to the results of serial finite element method as well as the analytical results.

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Journal of Thermal Analysis and Calorimetry
Authors: M. Sciacca, D. Milardi, M. Pappalardo, C. La Rosa, and D. Grasso

Abstract  

The failure of the ubiquitin-proteasome system is involved in many diseases. Here, in order to assess the pH-induced changes in the physico-chemical properties of ubiquitin, DSC measurements have been carried out at 2.5 physico-chemical properties of ubiquitin, DSC measurements have been carried out at 2.5

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Abstract

A positive unit point charge approaching from infinity a perfectly spherical isolated conductor carrying a total charge of +1 will eventually cause a negatively charged spherical cap to appear. The determination of the smallest distance ρ(d) (d is the dimension of the unit sphere) from the point charge to the sphere where still all of the sphere is positively charged is known as Gonchar's problem. Using classical potential theory for the harmonic case, we show that 1+ρ(d) is equal to the largest positive zero of a certain sequence of monic polynomials of degree 2d−1 with integer coefficients which we call Gonchar polynomials. Rather surprisingly, ρ(2) is the Golden ratio and ρ(4) the lesser known Plastic number. But Gonchar polynomials have other interesting properties. We discuss their factorizations, investigate their zeros and present some challenging conjectures.

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valuable insight in the first steps of the mechanism of the hydrodesulfurization reaction. By identifying the most reactive sites and the electrostatic potential in their vicinity, we will attempt to predict how chemical species will react with the surface

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would result in overall weaker interactions. Moreover, a lower degree of protonization also resulted in Cs powder to appear as aggregate formation. Meanwhile, as the film preparation took place in the acidic mediums, the electrostatic interactions tended

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