The structure of deformed bainite

Conclusion The bainitic structure is strengthened by a dislocation-slip mechanism and the main factor in obtaining high-strength cold-drawn wire is the formation of a stable substructure.Urals Polytechnical Institute. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 9, pp. 5–7, September, 1968.     

Phosphorus oxynitride: a thermally stable fire retardant additive for polyamide 6 and poly(butylene terephthalate)

The combustion performance of polyamide 6 (PA 6) and poly(butylene terephthalate) (PBT), both fire retarded by phosphorus oxynitride (PON), was studied by oxygen index (OI) and Underwriters Laboratory UL94 tests. It was shown that either PON alone or in combination with different co-additives is efficient in PA 6 and much less active in PBT. Thermogravimetric experiments provided evidence that PON promotes charring in both PA 6 and PBT. The mechanism of the char formation from PA 6 and PBT in the presence of PON was discussed on the basis of IR studies of solid residues produced in the thermal decomposition. The effective fire retardant action of PON in PA 6 is related to the interaction with the polymer to produce char, whereas the less effective activity of PON in PBT is related to the unfavorable acceleration of the evolution of combustible aliphatic fragments.     

Combined Impact of Magnetic Force and Spaceflight Conditions on Escherichia coli Physiology

Changes in bacterial physiology caused by the combined action of the magnetic force and microgravity were studied in Escherichia coli grown using a specially developed device aboard the International Space Station. The morphology and metabolism of E. coli grown under spaceflight (SF) or combined spaceflight and magnetic force (SF + MF) conditions were compared with ground cultivated bacteria grown under standard (control) or magnetic force (MF) conditions. SF, SF + MF, and MF conditions provided the up-regulation of Ag43 auto-transporter and cell auto-aggregation. The magnetic force caused visible clustering of non-sedimenting bacteria that formed matrix-containing aggregates under SF + MF and MF conditions. Cell auto-aggregation was accompanied by up-regulation of glyoxylate shunt enzymes and Vitamin B12 transporter BtuB. Under SF and SF + MF but not MF conditions nutrition and oxygen limitations were manifested by the down-regulation of glycolysis and TCA enzymes and the up-regulation of methylglyoxal bypass. Bacteria grown under combined SF + MF conditions demonstrated superior up-regulation of enzymes of the methylglyoxal bypass and down-regulation of glycolysis and TCA enzymes compared to SF conditions, suggesting that the magnetic force strengthened the effects of microgravity on the bacterial metabolism. This strengthening appeared to be due to magnetic force-dependent bacterial clustering within a small volume that reinforced the effects of the microgravity-driven absence of convectional flows.     

Fibre optic device for simultaneous laser power transmission and temperature measuring of irradiated object

A fibre optic device is described on the base of polycrystalline KRS-5 fibre for CO2-laser power transmission to the irradiated object and for simultaneous measurement of its temperature by its IR radiation.     

Photodeposition of silver can result in metal-enhanced fluorescence

Chemically deposited silver particles are widely used for surface-enhanced Raman scattering (SERS) and more recently for surface-enhanced fluorescence (SEF), also known as metal-enhanced fluorescence (MEF). We now show that metallic silver deposited by laser illumination results in an approximately 7-fold increased intensity of locally bound indocyanine green. The increased intensity is accompanied by a decreased lifetime and increased photostability. These results demonstrate the possibility of photolithographic preparation of surfaces for enhanced fluorescence in microfluidics, medical diagnostics, and other applications.     

Effect of structurization in oligomers on the temperature characteristics of their thermophysical properties

Results are shown of a study concerning the effect of oligomer block length and flexibility on the temperature characteristics of thermophysical properties, on the internal stresses, and on the structural transformations of oligomer systems.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 25, No. 2, pp. 330–335, August, 1973.     

Strength of a Composite Sheet Material in Impact Tension

A procedure and results of studies on the strength of a 2-mm PA6 shock-resistant composite sheet in impact tension are briefly outlined. Experimental investigations include static and impact tensile tests of specimens with a short test portion and sharp symmetrical edge notches. Acoustic emission methods used in the tests of specimens in static tension revealed acoustic signals that point to the development of damages in the material under loads much lower than the ultimate one. Test procedures are similar to those used earlier for testing sheet metals in tension. The wave process in the specimens upon impact tension was analyzed using the viscoelastic model. The influence of viscosity on the width of the wave front, determining stress growth rates upon its propagation, was established. According to the test results, the change from quasistatic to impact tension slightly changes maximum stress levels. Impact tension of notched specimens in the first wave of loading lower than the ultimate one produces a decrease in stresses with time that can be determined by viscosity and damage effects near sharp notches.     

Transmission Line for 258 GHz Gyrotron DNP Spectrometry

We describe the design and test results of the transmission line for liquid-state (LS) and solid-state (SS) DNP spectrometers with the second-harmonic 258.6 GHz gyrotron at the Institute of the Biophysical Chemistry Center of Goethe University (Frankfurt). The 13-meter line includes a mode converter, HE11 waveguides, 4 mitre bends, a variable polarizer-attenuator, directional couplers, a water-flow calorimeter and a mechanical switch. A microwave power of about 15 W was obtained in the pure HE11 mode at the spectrometer inputs.