Cobalt-based superalloys are common materials for the manufacturing of various components used in aerospace applications. Conventional cobalt-based with a unimodal grain structure generally exhibit low strength and ductility at high temperatures. A bimodal superalloy, Co–20Cr–15W–10Ni (CCWN), was designed to achieve both The deformation behavior tensile properties CCWN alloy fine-grain (FG), co...

BACKGROUND Ultrafine grinding is an environmentally friendly pretreatment that can alter the degree of polymerization, the porosity and the specific surface area of lignocellulosic biomass and can, thus, enhance cellulose hydrolysis. Enzyme adsorption onto the substrate is a prerequisite for the enzymatic hydrolysis process. Therefore, it is necessary to investigate the enzyme adsorption proper...

The titanium powder embedded with 2.5 vol% TiB was in-situ fabricated by gas atomization and applied for direct laser deposited (DLD) matrix composites. Consistent the network distributed boron-rich zone in composite powder, a three-dimensional (3D) ultrafine structure, consisting of nano-TiB whiskers (TiBw), characterized throughout as-fabricated (DLDed TiB–Ti). Both dendritic equiaxed network...

The conversion of magnetite to maghemite has been studied kinetically in the ultrafine particle range (77-220A) by chemical analysis. X-ray diffraction, and Mossbauer measurements. The reaction is third order. The activation temperatures are relatively low (8 250-1 1 200 K). Electron hopping in ultrafine magnetite powders is discussed on the basis of the results.

The root of Angelica gigas (Korean angelica) is traditionally used to treat women's ailments that are caused by an impairment of menstrual blood flow and cycle irregularities. This study evaluated the effect particle size of Korean angelica powder on its efficacy for treating estrogen-related symptoms of menopause. Initially, Korean angelica roots were pulverized into ultrafine powder, and oral...

BACKGROUND Airborne particles entering the respiratory tract may interact with the apical plasma membrane (APM) of epithelial cells and enter them. Differences in the entering mechanisms of fine (between 0.1 microm and 2.5 microm) and ultrafine ( <or= 0.1 microm) particles may be associated with different effects on the APM. Therefore, we studied particle-induced changes in APM surface area in ...

Centromeres are specialized chromosome domains that control chromosome segregation during mitosis, but little is known about the mechanisms underlying the maintenance of their integrity. Centromeric ultrafine anaphase bridges are physiological DNA structures thought to contain unresolved DNA catenations between the centromeres separating during anaphase. BLM and PICH helicases colocalize at the...

It is shown that thermomechanical treatment (TMT) of the EK61 superalloy with a strain rate (ε∙) 10−3 s−1 and gradual decrease in temperature from (0.92 – 0.65)Tδ leads to transformation initial coarse-grained structure into an ultrafine-grained (UFG) mixed type structure. Such UFG microstructure consists γ-phase grains δ-phase particles 0.3 μm size relatively large up 2 size. The having such e...

BACKGROUND Occupational exposures to ultrafine particles in the plume generated during laser hair removal procedures, the most commonly performed light based cosmetic procedure, have not been thoroughly characterized. Acute and chronic exposures to ambient ultrafine particles have been associated with a number of negative respiratory and cardiovascular health effects. Thus, the aim of this stud...

We investigated whether slowed clearance after exposure to ultrafine particles was due to a failure in alveolar macrophage phagocytosis. This was achieved by measuring the ability of a macrophage cell line (J774.2 MPhi) to phagocytose 2-microg indicator latex beads following 8-h exposures to a number of test particles. Particles utilized were fine titanium dioxide (TiO2), ultrafine titanium dio...