We investigate the point-particle limit of the equations of motion valid for a system of extended bodies in a scalar alternative theory of gravitation: the size of one of the bodies being a small parameter $\xi$. we calculate the limit, as $\xi$ tends towards 0, of the post-Newtonian (PN) acceleration of this small body. We use the asymptotic scheme of PN approximation, that expands all fields. We find that the PN acceleration A of the small body keeps a structure-dependent part at this limit. In particular, if the only massive body is static and spherical, then A differs from the PN acceleration of a test particle in a Schwarzschild field only by this structure-dependent part. The presence of the latter is due to the fact that the PN metric depends on the first spatial derivatives of the Newtonian potential. Since just the same form of PN metric is valid for the standard form of Schwarzschild's solution, the acceleration of a small body might keep a structure-dependent part at the point limit in general relativity also, depending on the gauge. The magnitude of the structure-dependent acceleration is already challenging on Earth. For the Pioneer spacecrafts, it is likely to discard the current version of the scalar theory. A modified version has been outlined in a quoted reference.

The thermosolutal instability of a layer of Rivlin-Ericksen elastico-viscous fluid is considered. A mathematical theorem disallowing the existence of neutral or unstable oscillatory motions in an initially bottom heavy thermosolutal convection configuration of the Veronis' [1] type with a quite general nature of bounding surfaces whenever the thermosolutal Rayleigh number is less than a critical value, is established.

In an applied magnetic field the ferrofluids behave optically anisotropic. In this work we present the microscopically observed patterns in transformer-oil magnetic fluid films in applied parallel and perpendicular magnetic fields and optically effects of these, especially the optical transmittance. The most interesting experimental observation is that concerning the time dependence of relative transmissivity, $\bar{T}_r$. For kerosene base ferrofluids $\bar{T}_r$ relax rapidly at coupling and decoupling magnetic field, but for a transformer-oil magnetic fluid the relaxation times can attain 3-5 minutes, depending on intensity of applied magnetic field.

Several detecting structures based on Resistive Plate Counters (RPCs) are evaluated for the use in a positron emission 3-D Complete Body Scan tomograph. The coincidence matrix is built for the specific detecting structure by means of random gamma pair rays generation, and then the filtered backprojection algorithm is used to reconstruct the original picture. The accuracy of image reconstruction is examined for the four different detecting structures.

Gaseous standards are necessary for the calibration of gas monitoring instruments used for the activity measurement of the gases discharged by nuclear power plants. A measuring system has been developed to standardize these radionuclides by the internal gas proportional counting method of measurement. It is simple and easy to operate. Using this measuring system, the activity per unit volume of the beta emitting gaseous radionuclides, such as ³H, ⁸⁵Kr and ¹³³Xe, can be measured accurately. Thus, samples of tritium gas were measured with a relative standard uncertainty less than 0.8%.

The RODOS is projected to run for multi-user operation at European scale in national nuclear emergency centres (responsible for off-site nuclear emergency management). Its development involves different stages of increasing complexity each of them called a prototype (PRTY) version which have to be customized by each participant country and validated in adequate accident scenarios. The present work underlines the results obtained by the Romanian RODOS Team at IFIN-HH with customization and validation of the most recent RODOS version (PRTY 5.0) taking into account tbe accident scenario for CANDU reactor and other specific Romanian conditions (the tritium issue, a more detailed geographical data base, associated costs of countermeasures, etc.).

The corrosion product formed on surface of the industrial Fe-C steel with low carbon concentration, after immersion in diluted ammonia solutions, have been investigated by means of ⁵⁷Fe Mössbauer spectroscopy. The amorphous Fe³⁺ oxyhydroxide is the major constituent of the corrosion layers. The corrosion product thickness increases with the change of the NH₃ concentration from 10^-1 M to 10^-4 M. All CEMS spectra show that there is a magnetic anisotropy on the surface of the samples.

A phenomenological theory based on the Landau - de Gennes expansion of the free energy density, for the re-entrance in lyotropics, is presented. The phenomenological coefficients and the order parameter temperature and concentration dependence for potassium laurate/decanol/water system showing re-entrant isotropic discotic nematic phase transition, are obtained.

The paper reports the results of local structure and microchemistry aspects of manganoan fayalite samples extracted from the Mn-Fe deposit of Razoare in the Romanian Carpathians. The microstructure of natural samples have been investigated by ⁵⁷Fe-Mössbauer technique (NGR), electron microscopy (BFTEM, DFTEM, SAED). A NGR-refined analysis of samples at room (RT) and LHe-temperature (LHeT), evidenced the several magnetic phases corresponding to olivines, the Fe and Fe-Mn oxides, the effects of super-paramagnetism in some samples, the ordering degree of Fe in cationic site of olivine structure. In correlation with the XRD and ND data on some synthetic Fe-Mn olivines, one established the dependencies of the unit cell parameters and M1, M2 polyhedron volume deformation around the metallic cations relative to iron content. The TEM investigations of natural mangangrunerite (formerly danemorite) assemblage (DA/138) have revealed the presence of precipitates and its identification: the FeO (wustite) and magnetite (Fe₃O₄).

In conventional spectrometers the transmission of light from the plasma to the spectrometer is done by lenses and/or mirrors. Fiber optics offer, in addition to low light loss on transport, the excellent opportunity of simultaneously coupling multiple spectrometer systems to the plasma without enormous space requirements or alignment difficulties. In this article we will describe an experiment using spark and ICP excitation to determine the advantages use the optical fibers. The use of optical fibers for light capture and transmission to the optics increases accuracy, reproducibility, sensitivity, long term stability, and flexibility of analytical system.

In this paper the optimal unitarity lower bound on logarithmic slope of the diffraction peak is investigated. It is shown that the unitarity lower bound is just the optimal logarithmic slopes predicted by the principle of least distance in space of states. A systematic tendency towards the saturation of the most forward-peaked limit is observed from all the available experimental data of all principal hadron-hadron (e.g., $PP$, $\bar{P}P$, $K^{\pm}P$, $\pi^{\pm}P$) scatterings practically at all laboratory momenta.

In this paper we introduce a new kind of nuclear/hadronic coherent particle production mechanism in high-energy collisions called dual coherent particle emission (DCPE) which takes place when the phase velocities of the emitted particle $v_{Mph}$ and that of particle source $v_{B_1 ph}$ satisfy the dual coherence condition: $v_{Mph} \le v^{-1}_{B_1 ph}$. The general signatures of the DCPE in the nuclear and hadronic media are established and some experimental evidences are given.

Studying integrals of the form $f_n(\alpha)=\int_{0}^{\infty}e^{-\alpha^2 x^2} x^{2n+1} K_{n}^{2}(x) dx$ with $n$ = 0, 1, ... an analytical expression for $n$ = 0 is first examined. Subsequently, simple parameterizations are proposed, which are valid to the percent level over a wide range of a values.

The forced oscillatory motion with damping is reviewed and amplification factors are defined and computed at resonance for displacement, velocity and acceleration. The amplification for external shocks is also estimated.