Experimental and theoretical studies enabled the reveal of patterns microstructure formation in surface layer Ti-6Al-4V titanium alloy subjected to ultrasonic impact treatment. The mixed amorphous nanocrystalline structure 200 nm thick uppermost dioxide TiO2 was demonstrated using transmission electron microscopy. 5 µm intermediate containing ? grains, 50–60 lower fragmented ?-Ti grains with re...

Icy grains in the interstellar medium and star-formation regions consist of a variety materials. Such composite interact differently with cosmic-ray (CR) particles compared to simple single-material grains. We aim calculate spectra energies temperatures mixed-composition undergoing whole-grain heating by CRs. The were assumed mixture carbon olivine, covered ices consisting oxides water. energy ...

Introduction: Many chondrules clearly contain relict grains that result from incomplete melting of precursor material. Most discussions of relict grains have focused on grains that are easy to identify because they have compositions significantly different from their host chondrules, including forsterite in type II chondrules and dusty olivine in type I chondrules [1]. However, in order to full...

The early Solar System contained short-lived radionuclides such as Fe (t1/2 = 1.5 Myr) whose most likely source was a nearby supernova. Previous models of Solar System formation considered a supernova shock that triggered the collapse of the Sun’s nascent molecular cloud. We advocate an alternative hypothesis, that the Solar System’s protoplanetary disk had already formed when a very close (< 1...

Barley (Hordeum vulgare) and wheat (Triticum aestivum) are often stored dry with 14% or less moisture, which during rainy periods may require that grains are dried after harvest. The hypothesis is that air-tight storage of high-moisture barley and wheat will increase nutrient digestibility due to chemical conversions prior to feeding. The objective was to evaluate the effect of high moisture co...

BACKGROUND Weight gain in the postpartum period is a risk factor for long-term obesity. Investigations of dietary intake among lactating and nonlactating overweight women might identify nutritional concerns specific to this population. OBJECTIVE To compare nutrient, meal, and snack intakes, food-group servings and prevalence of dieting among fully breastfeeding (BF), mixed breast and formula ...

the study of nucleation mechanism of new grains during severe plastic deformation of magnesium alloys is of great importance to control the characteristics of final microstructures.  to investigate the role of discontinuous recrystallization, a wrought az31 magnesium alloy was deformed by accumulative back extrusion process at 330 °c.  the obtained microstructures were studied using optical and...

Introduction: After silicon carbide (SiC), graphite is the best studied presolar mineral. A wealth of information exists on the isotopic compositions of C and of many minor/trace elements in micrometer-sized grains [e.g., 1-5]. Presolar graphite grains exhibit large C-isotopic anomalies with C/C ratios between 2 and 7000. Although this range is compatible with what is observed for SiC [6, 7], t...

From millimeter observations of classical T Tauri stars, it is suggested that dust grains in circumstellar disks have grown to millimeter size or larger. However, gas drag on such large grains induces rapid accretion of the dust. We examined the evolution of dust disks composed of millimeter sized grains, and showed that rapid accretion of the dust disk causes attenuation of millimeter continuu...

Presolar SiC grains of the types mainstream, Y, and Z are believed to have formed in thermally pulsing asymptotic giant branch stars with a range of metallicity: mainstream grains in stars of close-to-solar metallicity, Y grains in stars of around half-solar metallicty, and Z grains in stars of around one-third solar metallicity. From their Si and Ti isotopic ratios, it is possible to obtain in...