On the scale of “simultaneous” influence of several “hot” particles on the conditions of heat and mass transfer at ignition of liquid condensed substance

Processes of heat and mass transfer at igniting a film of a typical liquid burning substance—kerosene—by several small-size hot particles are investigated numerically. Characteristics of ignition by several particles are compared with similar parameters in a system of single hot particle-liquid fuel film-air. It is found out that a value of the interparticle distance affects characteristics of the process. Three possible regimes of ignition in a system of two hot particles-liquid fuel film-air, depending on the distance between the heat sources, are revealed.     

Friction in a Model of Hamiltonian Dynamics

We study the motion of a heavy tracer particle weakly coupled to a dense ideal Bose gas exhibiting Bose-Einstein condensation. In the so-called mean-field limit, the dynamics of this system approaches one determined by nonlinear Hamiltonian evolution equations describing a process of emission of Cerenkov radiation of sound waves into the Bose-Einstein condensate along the particle’s trajectory. The emission of Cerenkov radiation results in a friction force with memory acting on the tracer particle and causing it to decelerate until it comes to rest.

“A moving body will come to rest as soon as the force pushing it no longer acts on it in the manner necessary for its propulsion.”—— Aristotle     

The mechanics of particle accumulation structures in thermocapillary flows

The motion of small particles suspended in a cylindrical thermocapillary liquid bridge is considered. Owing to geometry and surface stresses the streamlines gather near the cylindrical free surface and provoke particle–free-surface collisions. We show numerically that tracers which are perfect but of finite size can accumulate on closed trajectories. A simple model is proposed to explain the attraction of particles to the closed trajectory based on the flow topology in the vicinity of a closed streamline which comes sufficiently close to the free surface and on particle–free-surface collisions which transfer particles among different streamlines.     

An analytic perturbation approach for classical spinning particle dynamics

A perturbation method to analytically describe the dynamics of a classical spinning particle, based on the Mathisson–Papapetrou–Dixon (MPD) equations of motion, is presented. By a power series expansion with respect to the particle’s spin magnitude, it is shown how to obtain in general form an analytic representation of the particle’s kinematic and dynamical degrees of freedom that is formally applicable to infinite order in the expansion. Within this formalism, it is possible to identify a classical analogue of radiative corrections to the particle’s mass and spin due to spin–gravity interaction. The robustness of this approach is demonstrated by showing how to explicitly compute the first-order momentum and spin tensor components for arbitrary particle motion in a general space–time background. Potentially interesting applications based on this perturbation approach are outlined.     

Investigation into the formation of X-ray photopolymer lenses

Two nondestructive methods of X-ray lens testing—X-ray microtomography and phase contrast introscopy—are analyzed and compared. Refractive lenses fabricated via laser stereolithography are used as a comparative object. The first samples of photopolymer lenses have been created via the rotation method, in which a capillary filled with a Dikhrom Lyuks liquid photopolymer is exposed to UV radiation during centrifuge rotation. Lens samples have been fabricated at the centrifuge’s angular velocities lying in the range from 3000 to 5000 rpm. The features of photopolymer transition from the liquid state into the solid phase under UV irradiation have been investigated to estimate their influence on the formation of the required shape of a refractive profile.     

Effect of the initial phase state of DT-matter on the compression of inertial fusion targets

We investigate the efficiency of inertial fusion target compression, where at the initial time moment the thermonuclear fuel is in a two-phase state and has the form of two adjacent layers — the external DT-liquid layer and the internal DT-ice layer. We study this problem for the fast ignition targets, where the ultimate final density of the thermonuclear matter is of a special importance. We take the simplest type of a fast ignition target, which corresponds to the technical justification of the HiPER Project aimed at demonstrating fast ignition at the compressing laser pulse energy ~100 kJ. Such a target presents a spherical DT-ice shell coated with a thin polymer film. We obtain the dependence of the final target density on the mass fraction of the DT-matter liquid phase and formulate the requirements on the admissible concentration of liquid phase if the decrease in the DT-fuel final density does not exceed 10%. We find the criterion for choosing the laser-pulse duration which provides the minimum decrease in the final density of the target containing DT-matter in the initial two-phase state.     

An insight into the interactions between LiN(CF3SO2)2 - γBL/DMF — PMMA by FTIR spectroscopy

FTIR spectroscopic analysis has been carried out for liquid electrolytes containing lithium —(trifluormethanesulfonimide or imide) salt as the ion source, a binary solvent composed of γBL and DMF and gel electrolytes containing PMMA. These studies illustrate that for all electrolytes, the cation (Li⁺) — solvent interaction is predominant and occurs through the carbonyl oxygen and the electron rich nitrogen atom of the solvating medium i.e., the binary solvent. Ionic conductivity trends upon varying lithium imide concentration, exhibit a single maximum in both liquid and gel polymeric electrolytes. The conductivity at 25 °C (σ₂₅) decline at high salt concentrations attributable to ion aggregation or cation-anion association, has been explained on the basis of detailed spectral analysis. Addition of PMMA as a gelatinizing agent to liquid electrolytes does not affect the conduction mechanism drastically, which is evident from conductivity measurements and is supplemented by spectral studies.     

Mathematical model of ree separation using heat oscillating extraction

The influence of periodical oscillations of the temperature on extraction and stripping processes in the extraction systems is studied. Two extraction system were investigated, No.1: 6M NaNO₃ — Nd(NO₃)₃ — Pr(NO₃)₃ — TBP — kerosene and No. 2: [Nd(NO₃)₃·3TBP] — [Pr(NO₃)₃·3TBP] — kerosene — 0.1M HNO₃. Mathematical model of the non-stationary membrane extraction is presented including the dependence of extraction rate constants on temperature. The values of activation energy for direct and reverse reactions of extraction and stripping reactions of Pr and Nd were calculated from experimental time dependencies of metal concentrations and temperature by solving reverse kinetics problem using the proposed mathematical model. Series of experiments with the effect of periodical temperature oscillations on the extraction system for separation of rare earth elements using bulk liquid membrane between two extractors were made. The mathematical model describes experimental data adequately. On the basis of the extraction rate constants and activation energies the optimization of the extraction process of separation of rare earth elements by liquid membrane under the effect of periodical temperature oscillations has been carried out. The optimal conditions of separation by liquid membrane were found: frequency and amplitude of thermal oscillations, liquid membrane flow rate and optimal ratio between organic and aqueous phase in the extractors.     

Search for WIMPs with enriched xenon at Gran Sasso

Summary A low-activity liquid-xenon scintillator is running at the Gran Sasso National Laboratory of INFN using liquid Kr-free xenon enriched at 99.5% in¹²⁹Xe. The result of adark matter direct search—looking also for the annual modulation effect—is presented. Preliminary exclusion plots both for coherent and spin-dependent coupled WIMPs are evaluated. The authors of this paper have agreed to not receive the proofs for correction.     

Development of carbon-carbon nozzle extension for liquid fuel rocket motors

Successful experience of RSC “Energy” and SPA “Iskra” in the development of carbon-carbon extension for oxygen-kerosene liquid fuel rocket motor has been summarized. Methodological approach that served to completion of carbon-carbon extension development in full and at comparatively small expenses has been described. Results of practical application of carbon-carbon extension for liquid fuel rocket motor 11D58M have been presented within the framework of International Space Program “Sea Launch”.     

Effect of local molecular ordering on the temperature behavior of the relaxation time of order-parameter fluctuations in the isotropic phase of PAA nematic liquid crystal

The behavior of the relaxation time of order-parameter fluctuations in the isotropic phase of PAA nematic liquid crystal was investigated on the basis of the spectra of depolarized (inelastic) light scattering in a wide temperature range including the immediate vicinity to the temperature of the nematic phase transition. The experimental data were analyzed within the Landau—de Gennes theory. The temperature limits of applicability of the Landau—de Gennes theory to the isotropic-phase dynamic properties are obtained. The minimum correlation length is determined, at which the effect of local ordering on the dynamics of slow orientational motion of isotropic-phase molecules is dominant.     

Massive particle’s tunneling radiation from higher-dimensional Schwarzchild de Sitte and Anti-de Sitter black holes

We investigate the massive particle’s tunneling radiation from Schwarzchild black holes in higher-dimensional de Sitter and Anti-de Sitter space-times. Difference from the mass-less particle, the geodesics of the massive particle is not light-like, but decided by the phase velocity. We focus on s-waves, extend Parikh and Wilczek’s semi-classical tunneling method, and calculate the massive particle’s emission rate. It is shown that the emission rate is relevant to the change of the black hole’s entropy respectively, and the result takes the same functional form as that of the mass-less particle.     

On the optimal void fraction in the thermodynamics of a simple liquid

The free energy of a crystal containing a given void fraction is derived in terms of the truncated interparticle Lennard-Jones potential. The free energy is minimized over the void fraction at constant pressure and temperature. It is shown that for all pressures the optimal void fraction remains less than 1% as the temperature is raised. However, at some temperature it grows suddenly and reaches values of the order of the percolation level for voids in a crystal, ∼0.125. At this point, the crystal transitions to the liquid state takes place. The derived dependence of the transition temperature on the pressure—the melting curve—is in good agreement with experimental data on the melting of solidified inert gases. Zh. éksp. Teor. Fiz. 116, 1375–1385 (October 1999)     

Experimental testing of liquid boiling-up homogeneity near the boundary of the attainable superheating

Results of measured average expectancy time of n-pentane and n-hexane boiling-up to the boundary of attainable superheating are presented. Experiments have been carried out in glass capillaries with substantially decreasing value of the superheated liquid volume for the preset metastable state (p, T = const). Obtained data fail to prove correlation 1 JVῑ = following from the condition of homogeneity and stationarity of the random process resulting in the superheated liquid boiling-up (J is the frequency of homogenous nucleation, V is the volume of the superheated liquid, ῑ is the average life time). Thus, experiments on superheated liquid boiling-up kinetics bound with measurements of average life time in glass capillaries cannot serve a proof of the validity of classical theory of nucleation for superheated liquids since one of the ground conditions — boiling-up homogeneity — is not met.     

Mach’s principle and the notion of time

The role of time coordinate in the realization of March’s principle is highlighted. It is shown that Mach’s principle is linked to the definition of a ‘particle’. These results suggest a deep connection between quantum gravity and Mach’s principle.     

Scanning near-field optical microscopy-based study of local dynamics of receptor-ligand interactions at the single molecule level

A scanning near-field optical microscope (SNOM)—based modification of the method to study the dynamics of single molecule receptor—ligand interactions exploiting the fluorescence imaging by total internal reflection fluorescence microscopy is introduced. The main advantage of this approach consists in the possibility to study the single molecule interaction dynamics with a subwavelength spatial resolution and a submillisecond time resolution. Additionally, due to the much smaller irradiation area and some other technical features, such a modification enables to enlarge the scope of the receptor—ligand pairs to be investigated and to improve the temporal resolution. We briefly discuss corresponding experimental set up with a special accent on the SNOM operation in liquid and present some preliminary results of related investigations.     

On the Electromagnetic Origin of Inertia and Inertial Mass

We address the problem of inertial property of matter through analysis of the motion of an extended charged particle. Our approach is based on the continuity equation for momentum (Newton’s second law) taking due account of the vector potential and its convective derivative. We obtain a development in terms of retarded potentials allowing an intuitive physical interpretation of its main terms. The inertial property of matter is then discussed in terms of a kind of induction law related to the extended charged particle’s own vector potential. Moreover, it is obtained a force term that represents a drag force acting on the charged particle when in motion relatively to its own vector potential field lines. The time rate of variation of the particle’s vector potential leads to the acceleration inertia reaction force, equivalent to the Schott term responsible for the source of the radiation field. We also show that the velocity dependent term of the particle’s vector potential is connected with the relativistic increase of mass with velocity and generates a longitudinal stress force that is the source of electric field lines deformation. In the framework of classical electrodynamics, we have shown that the electron mass has possibly a complete electromagnetic origin and the obtained covariant equation solves the “4/3 mass paradox” for a spherical charge distribution.     

Research on Hawking Radiation as Tunneling from Schwarzshild-anti-de Sitter Black Hole

After taking into account energy conservation and the particle’s self-gravitation interaction, Hawking radiation of the massive particle as tunneling from Schwarzshild-anti-de Sitter black hole is studied by using Parikh-Wilczek’s semi-classical quantum tunneling approach. Meanwhile, Hawking radiation as tunneling from the black hole is reexamined by developing Angheben–Nadalini–Vanzo–Zerbini (ANVZ) covariant method to cover energy conservation and the particle’s self-gravitation interaction. Both the results perfectly generalize those obtained by Parikh and Wilczek, and show that the tunneling rate is related to the change of Bekenstein-Hawking entropy, and the factual emission spectrum is not exactly thermal, but satisfies the underlying unitary theory. PACS: 04.70-s, 9760. Lf.