Numerical Investigation of Unsteady Heat Exchange in Ignition for Reactive Channel Walls by the Flow of a High-Temperature Viscous Gas

A study is made of the process of ignition of reactive channel walls by a laminar flow of hot gases, including the stages of heating of a substance and of reacting in the surface layer with self-acceleration of the chemical reaction. The process is determined by the heat exchange between the gas and the wall, the strength of the heat source in the chemical-reaction zone, and the sink of heat due to conduction in the radial and axial directions. In the stage of self-heating, we can have heat sink not only deep into the wall and/or through its external boundary but into the gas flow as well. The problem has been solved in a conjugate formulation. The influence of the temperature, the velocity of the gas at the entrance to the channel, and the wall thickness on ignition characteristics has been studied.     

Fracture mechanics approaches in the analysis of strains and fractures of bodies with notches and scotches

Fracture mechanics models and criteria for bodies with cracks have been developed to analyze strains and fractures of bodies with notches and scotches. Criterion equations and corresponding crack growth resistance diagrams for a body with a notch taking into account the changes in the degree of strain constraint at the notch apex due to finiteness of its apex radius rounding and a nonsingular stress component (T-stresses) have been considered. Analytical relations for calculating the J-integral in the case of bodies with blunt U-and V-notches under elastic and plastoelastic loading have been given. Capabilities of the method of separable functions for the experimental study of plastoelastic crack growth resistance for nonstandard samples with scotches have been presented.     

Above 16% efficient sequentially grown Cu(In,Ga)(Se,S)2‐based solar cells with atomic layer deposited Zn(O,S) buffers

We report the development of Cd‐free buffers by atomic layer deposition for chalcopyrite‐based solar cells. Zn(O,S) buffer layers were prepared by atomic layer deposition on sequentially grown Cu(In,Ga)(Se,S)₂ absorbers from Bosch Solar CISTech GmbH. An externally certified efficiency of 16.1% together with an open circuit voltage of 612 mV were achieved on laboratory scale devices. Stability tests show that the behavior of the ALD‐Zn(O,S)‐buffered devices can be characterized as stable only showing a minor drift of the open circuit voltage and the fill factor. Copyright © 2015 John Wiley & Sons, Ltd.     

Protective Effect of Water-Soluble C60 Fullerene Nanoparticles on the Ischemia-Reperfusion Injury of the Muscle Soleus in Rats

The biomechanical parameters of muscle soleus contraction in rats and their blood biochemical indicators after the intramuscular administration of water-soluble C₆₀ fullerene at doses of 0.5, 1, and 2 mg/kg 1 h before the onset of muscle ischemia were investigated. In particular, changes in the contraction force of the ischemic muscle soleus, the integrated power of the muscle, the time to achieve the maximum force response, the dynamics of fatigue processes, and the parameters of the transition from dentate to smooth tetanus, levels of creatinine, creatine kinase, lactate and lactate dehydrogenase, and parameters of prooxidant–antioxidant balance (thiobarbituric acid reactive substances, hydrogen peroxide, and reduced glutathione and catalase) were analyzed. The positive therapeutic changes in the studied biomechanical and biochemical markers were revealed, which indicate the possibility of using water-soluble C₆₀ fullerenes as effective prophylactic nanoagents to reduce the severity of pathological conditions of the muscular system caused by ischemic damage to skeletal muscles.     

The acoustic-emission properties of oxide tensosensitive indicators and signal recognition during the formation of cracks in a brittle coating layer

Russian Journal of Nondestructive Testing - The acoustic-emission properties of brittle oxide tensosensitive indicators (TS) coatings are considered, which are used not only for determining the...     

Calculation of combustion regimes for a twisted gas flow in a tubular ideal displacement reactor

Using the equations of the hydrodynamics of a twisted flow, we have employed a numerical method to construct the temperature and concentration fields of an exothermically reactive gas. We have analyzed the regimes of combustion and the mechanism involved in the ignition of the flow at various values of the twist parameter.Tomsk. Translated from Fizika Goreniya i Vzryva, No. 2, pp. 89–94, March–April, 1991.     

The effect of temperature on the water electrolysis reactions on nickel and nickel-based codeposits

Usually, an increase in the temperature of operation leads to a reduction in the voltage of operation of commercial water electrolyzers. The present work analyzes this effect in connection with the overpotential of the hydrogen and oxygen evolution reactions on electrodeposited nickel and some nickel-based codeposits which under normal operational conditions have shown good electrocatalytic characteristics. Results on pure nickel are also presented for comparison. A pressure chamber, adequate for electrochemical studies at high temperatures and pressures is described.