Application of FDS to Adhered Spill Plumes in Atria

In a recently published article (Poreh et al., Fire Saf J 43(5):344–350, 2008), Poreh et al. carried out a number of experiments in a small-scale atrium. They investigated the mass flow of the spill plume in case of fire emerging from an adjacent room or corridor. Based on these experiments, the equation for the mass flow rates of adhered spill plumes in atria was adjusted. In our article, we repeat the experiments in a computational fluid dynamics (CFD) program. The results agree well, both with the experiments and the suggested formula. After this first validation, large-scale CFD-simulations are carried out. It appears that the equation suggested by Poreh et al. is only valid in the case of a uniform smoke layer depth. If the smoke layer has a more complex configuration, the formula is no longer reliable for the design of the smoke and heat exhaust ventilation system.     

Effects of transglutaminase on the rheological and Mixolab thermomechanical characteristics of oat dough

The effects of added transglutaminase (TG) on the rheological and thermal properties of oat dough were evaluated. Mixolab, rheometer, and differential scanning calorimetry (DSC) were used to analyse the oat dough for changes in thermomechanical, rheological, and thermal properties. TG had distinct effects on dough water absorption, modified viscoelastic behaviour, and enhanced thermal stability. The dough also exhibited a decrease in the number of free amino groups after TG treatment, confirming protein cross-linking catalysed by TG. Electrophoresis of TG-treated oat protein fractions using SDS–PAGE, which was also used to analyse the effects of TG on the protein fractions of oat flour; it showed that both globulin and avenin were good substrates for TG.     

NOTE ON THE RATIONAL ANALYSIS OF CLAYS1

Several feldspars, muscovite, biotite and quartz, as well as diaspore clay and kao linite, in fairly pure state, were severally subjected to the procedure of “rational analysis” of clays. It was shown by analysis of the residues and solutions obtained:

• 1 That all the feldspars were attacked to a greater or less extent
• 2 That the micas were attacked more than the kaolinite
• 3 That kaolinite was not wholly decomposed by the treatment
• 4 That diaspore clay was not approximately decomposed by the treatment
• 5 That the amount of decomposition of all the substances depends to a considerable extent on the time and temperature of treatment.

As a result of these conclusions, it would not be possible to draw any conclusion as to the clay substance content of a particular clay from the results of a rational analysis.     

An estimation of the reflectivity of gold- and platinum-group metals alloyed with copper

The reflectivity of some noble metals alloyed with copper of the formula Cu _x M_1?x , where M is gold, platinum, palladium and silver, has been modelled using only the available optical constants of the pure parent metals, copper, gold, platinum, palladium and silver. The results are compared with experimentally determined reflectivity for some of these alloys and shown to give reasonable approximations, suggesting that the method has utility for the estimation of the reflectivity of alloys when no experimental data are available. The method of estimation of reflectivity has been extended to include two-phase alloys as well as homogenous alloys.     

Lower thrombolytic use for African Americans with myocardial infarction: an influence of clinical presentation?

BACKGROUND: After myocardial infarction, African Americans have been reported to undergo fewer catheterization and revascularization procedures than whites, but few studies have addressed racial variations in the delivery of thrombolytic therapy. METHODS: We conducted a retrospective analysis of data prospectively collected on consecutive patients admitted with acute myocardial infarction to the 16-bed coronary care unit of a large, urban teaching hospital. RESULTS: Over a 5-year period, 1948 consecutive patients were admitted with acute myocardial infarction to a single coronary care unit. Thrombolysis was administered to 19% of 1024 African Americans and 29% of 924 whites (P <.01). The initial diagnostic impression on admission was "definite" infarction less often in African Americans (30%) than in whites (43%, P <.001), a difference that appeared to largely account for the difference in thrombolytic administration in a multivariable model. Mortality adjusted for age and concomitant illnesses was similar in African Americans compared with whites (relative risk 1.0, 95% confidence interval 0.78 to 1.51). CONCLUSIONS: Much of the racial variation in thrombolytic administration could be accounted for by differences in clinical presentation, an issue that requires further study.     

Formation of Branched Ruthenium Nanoparticles for Improved Electrocatalysis of Oxygen Evolution Reaction

Branched nanoparticles are one of the most promising nanoparticle catalysts as their branch sizes and surfaces can be tuned to enable both high activity and stability. Understanding how the crystallinity and surface facets of branched nanoparticles affect their catalytic performance is vital for further catalyst development. In this work, a synthesis is developed to form highly branched ruthenium (Ru) nanoparticles with control of crystallinity. It is shown that faceted Ru branched nanoparticles have improved stability and activity in the oxygen evolution reaction (OER) compared with polycrystalline Ru nanoparticles. This work achieves a low 180 mV overpotential at 10 mA cm^?2 for hours, demonstrating that record‐high stability for Ru nanocrystals can be achieved while retaining high activity for OER. The superior electrocatalytic performance of faceted Ru branched nanoparticles is ascribed to the lower Ru dissolution rate under OER conditions due to low‐index facets on the branch surfaces.     

Hybrid nanocoatings in the display industry

Abstract— In the display industry, there is an increasing use of polymeric coatings comprising inorganic nanoparticles. These particles endow the coatings optical, electrical, or mechanical properties not attainable with organic materials, while the use of an organic binder allows easy processing via, e.g., wet deposition and UV or thermal crosslinking. Nanoparticles are relatively new materials and seem to offer numerous opportunities for new coatings for the display industry. Examples of this are silica nanoparticles in anti‐reflection coatings, indium‐tin‐oxide particles in antistatic coatings, and metallic carbon nanotubes in conductive coatings. Yet the physical interactions that determine the dispersion of nanoparticles in the wet formulation and the resulting morphology in the dry coating can be traced back to classical colloid science. In this paper, we focus on some of these principles and their application to nanoparticles dispersed in organic solvents. We illustrate these principles with several examples of anti‐reflection coatings, anti‐static coatings, and hardcoats currently in use in the industry.     

Inspection of power plant headers utilizing acoustic emission monitoring

Fossil power plant high energy, high temperature steam headers have been found to be susceptible to thermal fatigue assisted creep degradation. These mechanisms initiate and grow cracks in chrome molybdenum headers, from the bore hole edges and stub tube-to-header welds. Linking up of multiple cracks can lead to explosive expulsion of tubes and severe shorting of the header life. In order to extend the header life and operate safely, a better understanding of crack growth that may occur during specific plant operating conditions is needed. With that understanding, harsh operating conditions that may be causing excessive crack propagation and header damage can be curtailed. Acoustic emission monitoring of headers was performed to assist in identifying operating conditions that lead to header damage. This Electric Power Research Institute (EPRI) sponsored program found acoustic emission activity levels correlated to identified crack growth and analytically calculated stresses. Utilizing these results, draft EPRI guidelines have been developed to aid electric utilities in performing acoustic emission monitoring on superheater headers.     

Radial anisotropic growth of rhodium nanoparticles

In this contribution, we report the synthesis of rhodium multipods that result from a homogeneous seeded growth mechanism. Small Rh nanocrystal seeds were synthesized by the reduction of RhCl3 in ethylene glycol in the presence of PVP. These seed particles could be subsequently used, without isolation, to form larger rhodium nanoparticles. A reaction temperature of 190 degrees C led to isotropic cubic Rh particles. Lowering the reaction temperature resulted in more anisotropic growth, which gave Rh cubes with horns at 140 degrees C, and Rh multipods at 90 degrees C. The anisotropic growth occurred in the (111) direction, as determined by high-resolution TEM (HRTEM). Anisotropic growth proceeds via a seeded growth mechanism, and not by oriented attachment.