The magnetic moment of the 828 keV level in 115In

The magnetic moment of the 828 keV level in ¹¹⁵In was found to be 0.80 ± 0.14 μ_N by measuring the γ-γ integral angular correlation perturbed by an external magnetic field. Several assumptions concerning the nature of the state investigated have been discussed.     

Hollow Cathode Effect in a Long Perforated Cylindrical Cathode with External Coaxial Anode

The paper presents the main characteristics of transverse mode HCE glow discharges in spectral pure helium and neon and in a He/Ne mixture in a long perforated cylindrical cathode with an external coaxial anode. At optimum values of gas pressure, when HCE gets its climatic stage, the compact negative glow evenly “fills” the cathode cavity with maximum amplifications of current and radiation.     

Study of the basicity of some 1,2‐diazinium ylids

In this paper we present a study concerning the basicity of some new carbanion monosubstituted pyridazinium, 3‐methyl‐pyridazinium, 3‐(p‐halogenophenyl)‐pyridazinium and phtalazinium ylids. The pk_a values of the conjugated acids (salts) of ylids have been experimentaly determinated. Consequently, we have evaluated their basicity (k_b,) using the titration curves. The basicity depends mainly on the structure of the ylids carbanion itself, however the heterocycle's structures also has some influence on bacisity. Having in view the basicity, we have established certain correlations between basicity, structure and stability of the analised ylids.     

Approximation and Complexity: Liouvillean-Type Theorems for Linear Differential Equations on an Interval

Let u,v be solutions on an interval I of linear differential equations (LDEs) P=0 , Q=0 , respectively. We obtain a lower bound on the approximation of v by u in terms of bounds on the coefficients of LDE S _i =0 (for several i ), satisfied by the i th derivative of v and by the i th derivative of a basis of the LDE P=0 . One could view this result as a differential analog of the Liouville theorem which states that two different algebraic numbers are well separated if they satisfy algebraic equations with small enough integer coefficients. Unlike the algebraic situation, in the differential setting, in order to bound from below the difference |u-v| , we need to involve not only the coefficients of P,Q themselves, but also those of S _i . September 22, 2000. Final version received: March 11, 2001.     

Selecting the nature of imprinted molecular organosilica sieves with gallic acid via thermal analyses

The stability of the organosilica–gallic acid (GA) complex, and thus the strength of initial interactions which influences directly the sorption parameters of imprinted materials, is mostly given by the nature of co-monomers. Therefore, combining tetraethoxysilane, tetrametoxysilane, vinyl triethoxysilane and vinyl benzyl triethoxysilane as functional monomers, six formulations were obtained in order to optimise the nature of imprinted sieves. Vinyl benzyl trimethylammonium chloride and tertamethyl ammonium hydroxide directed the mesophase formation. Morphology and thermal properties of imprinted organosilica sieves were evaluated and compared to those of blank polymers synthesised in the same conditions as the imprinted ones but without GA. Thermal analysis results corroborated with the morphology of imprinted sieves were confirmed by specific GA sorption tests.     

Thermodynamic properties of tunneling quasiparticles in graphene-based structures

Thermodynamic properties of quasiparticles in a graphene-based structures are investigated. Two graphene superconducting layers (one superconducting component is placed on the top layered-graphene structure and the other component in the bottom) separated by oxide dielectric layers and one normal graphene layer in the middle. The quasiparticle flow emerged due to external gate voltage, we considered it as a gas of electron–hole pairs whose components belong to different layers. This is a striking result in view of the complexity of these systems: we have established that specific heat exhibits universal (?T³) behavior at low T, independent from the gate voltage and the superconducting gap. The experimental observation of this theoretical prediction would be an important step towards our understanding of critical massless matter.     

Stability problem for pendulum-type motions of a rigid body in the Goryachev-Chaplygin case

We consider the motion of a rigid body with a single fixed point in a homogeneous gravity field. The body mass geometry and the initial conditions for its motion correspond to the case of Goryachev—Chaplygin integrability. We study the orbital stability problem for periodic motions corresponding to vibrations and rotations of the rigid body rotating about the equatorial axis of the inertia ellipsoid.In [1], it was proved that these periodic motions are orbitally unstable in the linear approximation. It was also shown that, to solve the stability problem in the nonlinear setting, it does not suffice to analyze terms up to the fourth order in the expansion of the Hamiltonian function in the canonical variables.The present paper shows that in this problem one deals with a special case where standard methods for stability analysis based on the coefficients in the normal form of the Hamiltonian of the perturbed equations of motion do not apply. We use Chetaev’s theorem to prove the orbital instability of these periodic motions in the rigorous nonlinear statement of the problem. The proof uses the additional first integral of the Goryachev—Chaplygin problem in an essential way.