Site-specific endonuclease from thermophilic Bacillus species MK strain is isoschizomer of SalI

Screening of thermophilic bacterial strains revealed a strain containing site-specific endonuclease BspMKI. This endonuclease was purified to functional homogeneity during sequential chromatographic steps. The enzyme recognizes sequence 5'-G decreases TCGAC-3' on DNA molecule and is isoschizomer of endonuclease SalI. The molecular mass of BspMKI is about 45 kD. The enzyme is maximally active at 55 degrees C and MRB (50 mM NaCl, 10 mM Tris-HCl, pH 7.4, 10 mM MgCl2, 1 mM dithiothreitol) is the optimal buffer. The enzyme is highly stable and retains its activity during two weeks at room temperature.     

Method of Power Adaptation for Signals Emitted in a Wireless Network in Terms of Neuro-Fuzzy System

Wireless Personal Communications - Attenuation of the signal propagating between the emitting and receiving antennas in a wireless network requires adaptation of the power of the emitted signal for...     

Determination of the Parameters of the Two-Parametric Fracture Mechanics along the Crack Front Based on the Digital Image Correlation Data

A mathematical processing technique and an algorithm for the numerical correction of experimental displacement fields on the specimen surface in the vicinity of a crack tip with consideration of the displacement of a body as a rigid whole under its loading and the actual position of a crack tip were proposed. The initial experimental displacement fields in the vicinity of a fatigue crack tip of a compact specimen were determined by digital image correlation. This approach was successfully used for a compact specimen and the possibility of its expansion to obtain the distributions of the stress intensity factors and the nonsingular T stresses along the spatial crack front was shown.     

Ligand Shell Engineering to Achieve Optimal Photoalignment of Semiconductor Quantum Rods for Liquid Crystal Displays

The photoalignment process to align semiconductor quantum rods (QRs) in the liquid crystal monomer (LCM) matrix is a flexible technology; however, the optical quality of the resulting enhancement films drops at high concentrations of the QRs. The compatibility between the ligand shell on the QRs and the LCM plays an important role in avoiding this issue. Herein, several kinds of ligand shells on the rod‐in‐rod CdSe/CdS QRs are designed, without affecting the optical properties of QRs, and their compatibility with LCM molecules is studied. Promesogenic dendritic ligands in combination with relatively short alkylphosphonic acids are found to provide the highest optical quality, without QR aggregation, and so the high brightness of the resulting enhancement films, even at higher concentrations of QRs in LCM, which is perfectly suitable for the application in liquid crystal displays.     

Analysis of permissible dimensions of cracklike defects based on a diagram of crack-growth resistance

Determination of permissible dimensions of cracklike defects with a finite fillet radius of its tips is based on the diagram of crack-growth resistance introducing a safety factor into a criterion equation. Calculation formulas are suggested to estimate the safety factors and permissible dimensions of plane cracklike defects. The influence of a theoretical stress concentration factor and safety factor of yield strength on the safety factor was also investigated. An analysis of permissible dimensions of a cracklike defect demonstrated on an example of a tensile plane with a through cracklike defect allows one to permit larger (in comparison with crack) dimensions of the safe cracklike defect.     

Approaches of fracture mechanics in the analysis of admissible defects in the form of notches

The evaluation of the structural strength of elements with defects in the form of notches is performed by using the equation of the diagram of crack-growth resistance based on the criterion of averaging of stresses in the process zone and the analysis of the strain constraint near the tip of the notch. The admissible (safe) state of an element with defect is determined by introducing the safety factors in the criterional equation.     

Oxygen release from SrCo0.8Fe0.2O3 − δ

We have studied oxygen release from a membrane material with the composition SrCo_0.8Fe_0.2O_{3 ? δ} of various sizes in the temperature range 600–900°C in a flow reactor at oxygen partial pressures from 0.2 to 10^?5 atm. The results demonstrate that the oxygen release from samples 50 μm to 2 mm in size at temperatures above 800°C can be described in terms of a quasi-equilibrium model. For fine powders, ≤63 μm in size, the temperature range of quasi-equilibrium oxygen release begins at t ≥ 600°C.     

Modeling of hydrodynamics and separation in a hydrocyclone

A numerical study of the flow pattern and the separation processes in a hydrocyclone was performed on the basis of the Navier-Stokes equations. The mathematical model presented here enabled us to calculate the separation characteristics and the distributions of the particle velocity, pressure, and particle concentration in the apparatus.     

Detection of trace quantities of10B in biosamples using track detectors

A new variant of a solid-state detector adapted for estimating the¹⁰B content in biological tissue was developed. A new polymeric composition based on oligoester acrylates was used as the detector. The number of tracks is a linear function of the boron content in the concentration range 0.5–200 μg¹⁰B/g inbiological sample samples with mass 100–500 μg. The detector can be recommended for deterning¹⁰B in biological tissues, mineralogy, and agrochemistry, 3 figures, 2 references. Translated from Atomnaya énergiya, Vol. 88, No. 3, pp. 194–197, March, 2000.