Detonation of fuel-air mixtures above the surface of the earth

Moscow. Translated from Fizika Goreniya i Vzryva, Vol. 24, No. 2, pp. 124–126, March–April, 1988.     

Propellant performance of organic explosives and their energy output and detonation velocity limits

Methods for determining the propellant performance of high explosives (HEs) are considered. The common and distinguishing features of the techniques of end acceleration of plates and shell expansion are shown. Experimental data on the propellant performance of individual explosives are given. The influence of metal additives on the brisance (propellant performance) and blast effect of explosive compositions is considered. A theoretical method for estimating the propellant performance is proposed, and the propellant performance of hydrogen-free HEs is calculated using experimental data on the enthalpies of formation and densities of single crystals. The energy output and detonation velocity limits of organic HEs are considered and estimated. Promising directions in the investigation of the properties of HEs are considered. __________ Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 1, pp. 99–111, January–February, 2007.     

Evolution of ICRP Models for Taking into Account the Irregularity of Irradiation over Time When Assessing Radiation Risk

Atomic Energy - The authors’ point of view, as expressed in publications, on the evolution of models taking into account the irregularity of irradiation in time, which are contained in the...     

Mechanical Properties of Joints in Friction Stir Welding of Aluminum Alloys

Russian Engineering Research - Friction stir welding of butt joints in aluminum alloys is considered. Experiments show that, with disruption of the welding temperature and time, defects localized...     

Dual-wavelength superfluorescent fiber emitter

The feasibility of constructing a dual-wavelength, spatially single-mode, superfluorescent fiber emitter on the basis of erbium optical fibers with pumping by multimode semiconductor lasers is demonstrated. The emitter is fabricated by all-fiber technology and has a power output in excess of 10 mW, an average emission wavelength of 1.54 μm, and a spectral resolution of 27.5 nm at component linewidths of 3 nm and 9 nm. The depolarization of the radiation from the emitter as it propagates in an anisotropic, single-mode fiber waveguide is investigated. Pis’ma Zh. Tekh. Fiz. 23, 37–42 (October 26, 1997)     

Determination of Residual Stresses in Electro-Spark Deposited Coatings

We propose a method of determining axial residual stresses in prismatic coated rods of rectangular cross section, which provides a means to study the stress state in both homogeneous and inhomogeneous coatings.     

A Non-cooperative Uplink Power Control for CDMA Wireless Communication System

In this project, the main focus is to enhance the existing power control algorithm that is applied in a single cell of CDMA network. Nash algorithm is selected and is further improved with modification of its cost function with a value as power of target SINR, which to reduce the SINR error at first iteration, so as to increase the rate of convergence effectively. Decision of a value is important to ensure the SINR error is reduced at first iteration. The uniqueness and algorithm convergence of enhanced cost function is proven with certain conditions requirements. Therefore, enhanced Nash algorithm (ENA) is proposed which only applicable in first iteration of power control method. The rest of iterations are applied by Nash algorithm due to its better convergence to target SINR. After simulations, with consideration of Rayleigh and Rician fading channels, a significant increase in rate of convergence while maintaining the SINR with error less than 0.01 is shown. The transmitted power is lower in some scenarios, or with very slight reduction less than 0.5%. The SINR error at first iteration is reduced about 20% more by using ENA. In overall, ENA has better performance than the existing Nash algorithm in terms of transmitted power and rate of convergence, without compromising SINR.

     

Quantum frequency standards

A brief review of quantum frequency standards development since the early stage of quantum radiophysics is presented. The level of performance achieved and various applications in science and technology prove that the quantum frequency standards are a classical example of the remarkable impact of quantum radiophysics into 20th century civilization     

Reduced graphene oxide

This paper describes a novel approach to the preparation of reduced graphene oxide and its dispersions in organic solvents. Graphite oxide, graphene oxide, and reduced graphene oxide have been prepared and characterized by a variety of physicochemical techniques.     

Designing elements of protection against electrostatic discharges for high-frequency CMOS circuits

A new electric circuit layout and physical structure are proposed for an element of protection against electrostatic discharges. The new element features a twofold smaller resistance to the electrostatic discharge current. The reduced resistance is obtained by using additional transistors implementing feedback. The use of the new electric circuit layout and a new simulation technique that takes into account substrate transistors allows reductions in the element’s area and its electric capacitance by factors of 1.5 and 1.6, respectively.