Laser Desorption of Traces of Explosives in Ion Mobility Spectrometry

The efficiency of a YAG:Nd3+laser (λ = 1064 nm) and a diode continuous laser (λ = 440 nm) to initiate laser desorption of traces of trinitrotoluene (TNT) and cyclotrimethylenetrinitramine (RDX) is quantitatively compared with use of mass spectrometry. It is shown that a pulsed neodymium laser is more promising for creating a device of contactless sampling for ion mobility spectrometers

Influence of the photon - neutrino processes on magnetar cooling

The photon-neutrino processes $\gamma e^{\pm} \to e^{\pm} \nu \bar \nu$, $\gamma \to \nu \bar \nu$ and $\gamma \gamma \to \nu \bar \nu$ are investigated in the presence of a strongly magnetized and dense electron-positron plasma. The amplitudes of the reactions $\gamma e^{\pm} \to e^{\pm} \nu \bar \nu$ and $\gamma \gamma \to \nu \bar \nu$ are obtained. In the case of a cold degenerate plasma contributions of the considering processes to neutrino emissivity are calculated. It is shown that contribution of the process $\gamma \gamma \to \nu \bar \nu$ to neutrino emissivity is supressed in comparision with the contributions of the processes $\gamma e^{\pm} \to e^{\pm} \nu \bar \nu$ and $\gamma \to \nu \bar \nu$. The constraint on the magnetic field strength in the magnetar outer crust is obtained.Comment: 8 pages, LaTeX, 2 PS figures, based on the talk presented by D.A. Rumyantsev at the XV International Seminar Quarks'2008, Sergiev Posad, Moscow Region, May 23-29, 2008, to appear in the Proceeding

Matter-induced vertices for photon splitting in a weakly magnetized plasma

We evaluate the three-photon vertex functions at order $B$ and $B^{2}$ in a weak constant magnetic field at finite temperature and density with on shell external lines. Their application to the study of the photon splitting process leads to consider high energy photons whose dispersion relations are not changed significantly by the plasma effects. The absorption coefficient is computed and compared with the perturbative vacuum result. For the values of temperature and density of some astrophysical objects with a weak magnetic field, the matter effects are negligible.Comment: 14 pages, 1 figure. Accepted for publication in PR

Organizational factors for manufacturing defects reduction in small batch production

The study is devoted to the defects organizational causes analysis in the machine building products production process. The companies with the small batch production were taken into consideration. Factors related to the time norms fulfilling percentage, the work rhythm, the consolidation of operations at one workplace, the new technologies introduction and equipment failures were chosen. A preliminary factors selection according to independence criteria allowed us to build a reliable regression model for the defects rate calculating. The main factors influencing the defects rate in small batch production are the time norms fulfilling percentage, the rate of consolidation of operations at one workplace, and the number of new technological processes introduced. This allowed us to offer recommendations on the machining sites work organization. The final operations and productswhich are made from expensive metals should be carried out at workplaces with a low rate of operations consolidation. Also, it is important that the wage system should not contribute to over-fulfillment of norms. The maintenance and repair system should prevent malfunctions during operations fulfilment. © Published under licence by IOP Publishing Ltd

Neoglycolipids Micelle-like Structures as a Basis for Drug Delivery Systems

Targeted drug delivery is one of the most promising tasks of nanomedicine, as this is a real way to increase the effectiveness of therapeutic effects against many diseases. In this regard, the development of new inexpensive highly effective stimulating and non-immunogenic drug delivery systems (DDS) is of great importance. In this work new molecular candidates were proposed and studied for the creation of such systems based on the use of new compounds, neoglycolipids. It is shown that these compounds are capable of self-association in aqueous solutions and can serve as potential carriers of drug compounds with targeted delivery determined by their terminal groups (in particular, glycans). The processes of their associates formation and features of their structure are investigated. The results show that these selforganizing nanoscale systems can be used as a basis for developing new drug delivery systems. Keywords: neoglycolipids, micelle-like structures, small-angle X-ray scattering, molecular dynamics simulatio

Formation of "Lightnings" in a Neutron Star Magnetosphere and the Nature of RRATs

The connection between the radio emission from "lightnings" produced by the absorption of high-energy photons from the cosmic gamma-ray background in a neutron star magnetosphere and radio bursts from rotating radio transients (RRATs) is investigated. The lightning length reaches 1000 km; the lightning radius is 100 m and is comparable to the polar cap radius. If a closed magnetosphere is filled with a dense plasma, then lightnings are efficiently formed only in the region of open magnetic field lines. For the radio emission from a separate lightning to be observed, the polar cap of the neutron star must be directed toward the observer and, at the same time, the lightning must be formed. The maximum burst rate is related to the time of the plasma outflow from the polar cap region. The typical interval between two consecutive bursts is ~100 s. The width of a single radio burst can be determined both by the width of the emission cone formed by the lightning emitting regions at some height above the neutron star surface and by a finite lightning lifetime. The width of the phase distribution for radio bursts from RRATs, along with the integrated pulse width, is determined by the width of the bundle of open magnetic field lines at the formation height of the radio emission. The results obtained are consistent with the currently available data and are indicative of a close connection between RRATs, intermittent pulsars, and extreme nullers.Comment: 24 pages, no figures, references update

LASER RADIATION AS A WAY TO CONTROL THE ANALYTICAL PARAMETERS OF FIELD ASYMMETRIC ION MOBILITY SPECTROMETER FOR DETECTION OF EXPLOSIVES IN VAPOR PHASE

In this study we compare a radioactive 63Ni ionization source with a laser ionization source and reveal the parameters of laser ionization of TNT, RDX, HMX and PETN which can lower the limit of detection of portable devices. We also determine nonlinear ion mobili-ties at different conditions.Работа выполнена в рамках финансируемого РФФИ (Российский фонд фундаментальных исследований) проекта № 19-32-90280

Instability of Democracy as Resource Curse

We suggest a dynamic game theoretic model to explain why resource abundance may lead to instability of democracy. Stationary Markov perfect equilibria of this game with four players – Politician, Oligarch, Autocrat and Public (voters) – are analyzed. Choosing a rate of resource rent tax, potential Autocrat competes with conventional Politician for the office, and Oligarch, the owner of the resource wealth, bribes Politician to influence her decisions. Actual Autocrat's tax policy may be different from the announced one. If the difference is large, then Public may revolt or Oligarch may organize a coup to throw Autocrat down. It is shown that the probability of democracy preservation is decreasing in the amount of resources if the institutional quality is low enough. It does not depend on the amount of resources, if the institutional quality is higher than a threshold. The level of the threshold, however, depends positively on the resource wealth. We have found also that under very low institutional quality, a paradoxical effect takes place: the probability of democracy preservation may decrease with small improvements of institutional quality. It is shown as well that Oligarch earns larger part of rent under democracy than under autocracy. This result conforms to empirical observation which is demonstrated in the paper: under low quality of institutions, democratization leads to higher inequality and inequality entails worsening of the attitude to democracy