Energy release of mixed explosives during propagation of a nonideal detonation under conditions similar to the operation conditions of a blasthole charge

Detonation experiments were performed in a specially developed explosive device simulating a blasthole using charges of fine-grained and coarse-grained (granular) 30/70 TNT/ammonium nitrate mixtures of identical density 0.89 g/cm³ in steel shells with an inner diameter of 28 mm and a wall thickness of 3 mm at detonation velocities of 4.13 and 2.13 km/sec, respectively. Despite significant differences in detonation velocity (pressure), identical expansion of the charge shells was observed. On the other hand, numerical simulations of detonation propagation in the explosive device with the corresponding velocities ignoring the possibility of energy release behind the shock front show that the expansion of the charge shell is always greater in the case of a high-velocity regime. It is concluded that under the conditions simulating detonation propagation and the work of explosion products in a blasthole, effective additional energy release occurs behind the low-velocity (nonideal) detonation front. __________ Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 4, pp. 111–120, July–August, 2007.     

Fibre materials based on ultrahigh-molecular-weight polyethylene and montmorillonite nanoparticles

The effect of the thermodynamic quality of the solvent on the properties of polymer solutions was determined. Thermal annealing affects formation of the structure and the mechanical properties of UHMPE. Fourier transform IR spectroscopy revealed the effect of the filler on the structure of the polymer matrix. The morphology of filled UHMPE fibres was characterized by optical microscopy; the fibres have a longitudinally oriented structure and the filler aggregates in particles up to 50 μm in size, which does not allow classifying the materials obtained as nanocomposites. Translated from Khimicheskie Volokna, No. 3, pp. 4–8, May–June, 2008.     

Main results of the work accomplished at ZAO Interavtomatika for 15 years

Main results of the activities carried out by ZAO Interavtomatika in the Russian market of power engineering are presented. Main lines of activities are described, the results of putting in use control systems are analyzed, and prospects for their further development are presented.     

Study of a Spherical-Pad Head Slider for Stable Low-Clearance Recording in Near-Contact Regime

A slider with an air-bearing surface that has a small spherical pad around the read/write elements on the trailing center pad was developed to reduce the meniscus and friction forces and slider clearance loss. While the slider which has a spherical pad of a radius less than 10 mm, the meniscus force is reduced to less than 10% of the air-bearing lift force, thus, flying height modulation is decreased and instability are suppressed. Evaluation using an air-bearing surface model with a spherical pad showed that slider clearance was increased by 1 nm at a 5-nm nominal flying height. Evaluation using touchdown-takeoff testing of a spherical pad slider fabricated by depositing carbon on the center pad air-bearing surface by means of the lift-off resist technique showed that the spherical pad slider had a very small friction force and acoustic emission output up to a 5-nm interference height. It thus provides instability-free sliding in the near-contact regime.     

基于ESB的企业应用集成研究

首先分析了传统EAI的不足——使用私有化的技术来连接企业的各个系统，初始投资非常大，并且无法满足企业所需的商业敏捷性，随后提出了基于企业服务总线（ESB）的解决方案。该方案建立在面向服务架构的基础之上，通过使用简单的标准适配器和接口，来完成粗粒度应用（服务）和其他组件之间的互操作，能够满足大型异构企业环境的集成需求。它将使企业应用集成更加方便、灵活、可靠，伸缩性也更强。     

Continuous-wave operation of 1.30μm GaAsSb/GaAs VCSELs

1.30 μm VCSELs using GaAsSb quantum wells, which operate continuous-wave at and above room temperature (RT), are reported. A threshold current as low as 1.2 mA at RT and a maximum CW operating temperature of 70°C are demonstrated     

Low-threshold operation of 1.3-μm GaAsSb quantum-well lasersdirectly grown on GaAs substrates

GaAsSb quantum-well (QW) edge-emitting lasers grown on GaAs substrates were demonstrated. The optical quality of the QW was improved by optimizing the growth conditions and introducing a multi-QW to increase the gain. As a result, 1.27-μm lasing of a GaAs_0.66 Sb_0.34-GaAs double-QW laser was obtained with a low-threshold current density of 440 A/cm², which is comparable to that in conventional InP-based long-wavelength lasers. 1.30 μm lasing with a threshold current density of 770 A/cm² was also obtained by increasing the antimony content to 0.36. GaAsSb QW was found to be a suitable material for use in the active layer of a 1.3-μm vertical-cavity surface-emitting lasers     

The problem of motion correction with Gaussian communications channel

A problem of correction of motion of a multistep linear controlled system under mixed perturbations is considered. It is supposed that the a center observes and controls the system; the center is connected to the system with a noisy communications channel. The influence of communications constraints on parameters of motion correction is studied. Formulae for error of reconstruction of a transient vector and optimal value of quality functional are obtained. A series of results is illustrated by an example.     

Development and application of application-specific FPGA-based processor for solving bioinformatics problems

An approach to solving large resource-consuming problems is proposed based on the application of field-programmable gate array (FPGA) microchips. This approach is demonstrated for application to the problems of searching for common motifs in genetic sequences of regulatory regions of various genes. Due to the high degree of parallelization and high transmission capacity of the internal memory in the employed FPGA crystal, a 60-fold increase in performance was achieved in solving this problem compared to a system based on the CUDA technology and about a 2000-fold increase compared to a personal computer.     

Results of experimental studies of the thermohydraulic processes during condensation of superheated steam inside an inclined tube

This article presents new results of an experimental study of the process of condensation of superheated water vapor inside inclined tubes as applied to air-cooled condensers of steam-turbine plants.