Effect of copper chromite and copper chromitecopper oxide mixture catalysts on the thermal decomposition of ammonium perchlorate and composite solid propellant

Thermal decomposition of powdered ammonium perchlorate (AP), polystyrene (PS) and $\text{AP}\text{PS}$ propellant, catalysed by freshly-prepared CuCr₂O₄ and mixtures of CuCr₂O₄ and CuO, has been studied with a low concentration (1% by mass) of the catalysts. It appears that decomposition is increased due to heterogeneous catalysis. The kinetics of thermal decomposition of AP in the presence of CuCr₂O₄ in the orthorhombic region of AP have also been studied.     

Performance monitoring of the EC - 1030 system by a microprocessor - based monitor

This paper presents a M6800 microprocessor based hardware monitor for measuring certain selected parameters of the EC-1030 computer system. The motivation for this work was to get an insight into the operation of the system under the present work load and use these results towards improvement and design studies. The three main classes of quantitative indices of computer system performance/productivity, responsiveness and use have been measured using hardware and software tools. This paper describes the hardware monitor design and discusses the measurements made.     

Particles settling studies using ultrasonic techniques

Effects of acoustic velocity and attenuation measurements during settling of 43-, 110- and 168-μm glass beads in water are reported. Ultrasonic waves were generated at a frequency of 3.2 MHz. An abrupt increase in acoustic velocity and a sharp peak in the attenuation characterized the onset of settled bed. The observed attenuation peak at the transition between suspended and settled bed was attributed to dissipation caused by viscous absorption losses. The critical concentration at which increase in acoustic velocity and attenuation peak occurred was estimated for these particle sizes.     

Correlating Photoluminescence and Photocatalytic Activity of Mixed-phase Nanocrystalline Titania

Mixed-phase nanocrystalline titania with varying rutile-content has been synthesized via solvent mixing and calcination treatment of sol–gel derived nanocrystalline anatase and rutile precursors. The mixed-phase nanocrystalline titania has been characterized using different analytical techniques for analyzing their phase contents, nanocrystallite size distribution, band-gap, and photoluminescence. The photocatalytic activity of mixed-phase nanocrystalline titania has been studied by monitoring the degradation of methylene blue dye in an aqueous solution under ultraviolet-radiation exposure. A strong correlation between photoluminescence and photocatalytic activity has been demonstrated for the mixed-phase nanocrystalline titania.     

AN IMPROVED PENG-ROBINSON EQUATION OF STATE WITH A NEW TEMPERATURE DEPENDENT ATTRACTIVE TERM

An improved form of the Peng-Robinson cubic equation of state has been proposed. The temperature dependence of the attractive term has been modified so as to accurately represent vapor pressures of several fluids with large acentric factors from triple point to close to the critical point. The prediction of saturated liquid volume is also improved by introducing volume translation term in the equation of state. Comparisons of theoretical results with experimental data are made for the vapor/liquid phase equilibria of 44 pure fluids including nonpolar, polar and associating fluids. Our results show that the modified Peng-Robinson equation of state can represent accurately saturated vapor pressures of the fluids investigated in this paper, and it is more accurate than the Peng-Robinson equation of state and its earlier modifications due to Stryjek and Vera (1986) and Twu et al. (1995rpar;. Incorporation of the volume translation term in the equation of state has been found to improve the accuracy of saturated liquid volume significantly.     

Photoelectrochemical study of passive films on aluminum

Photocurrent spectroscopy and Photoelectrochemical Laser Imaging (PECLI) were performed on passive films on aluminum. Cathodic photocurrents were measured between 2.7 and 6.9 eV. Photoelectrochemical laser images of the oxide covered aluminum surface were recorded in the presence of non-corroding (no Cl⁻) and corroding (Cl⁻) electrolyte.     

Electron microscopic demonstration of an adenovirus in the hepatocytes of birds experimentally infected with hydropericardium syndrome

The final part of this series attempts to evaluate the relevance of Nazi medicine for doctors today. Euthanasia, informed consent, the conflict of interests of the individual versus those of society and racism were as prominent themes of Nazi medicine as they are today. It would be foolish not to learn from experiences of the past. Nazi medicine can therefore never be an irrelevant subject of the days gone by.