in this study, ultrafine grained 2024 al alloy based b4c particles reinforced composite was produced by mechanical milling and hot extrusion. mechanical milling was used to synthesize the nanostructured al2024 in attrition mill under argon atmosphere up to 50h. a similar process was used to produce al2024-5%wt. b4c composite powder. to produce trimodal composites, milled powders were combined w...

a nano/ultra-fine grain al-0.2wt% zr alloy was produced by accumulated roll bonding (arb) processafter 10 cycles. the fraction of high angle grain boundaries increased from 8% to 65.4% during 10passes during arb process. this alloy was subjected to tensile test at different temperatures (523,573and 623 k) and strain rates (0.1 and 0.01 s-1). the optimum condition of temperature and strain rate ...

several studies suggest that invertebrate abundance and richness are disrupted and reset at confluences. thus, junctions contribute disproportionately to the overall aquatic biodiversity of the river. in general terms, authors have reported high abundance and diversity due to the major physical heterogeneity at junctions. however, data are still scarce and uncertainties are plentiful.the impact...

this study investigates the influence of some chemical additives such as methanol, ethanol, sodium oleat, chloroform and sodium hexametaphosphate (shmp) on the dry fine grinding of calcite (x50= 33 µm) using a stirred media mill. the experiments were carried out by a batch operation, and the change in colour properties (ry, whiteness and yellowness) of calcite powder. the results showed that th...

the dynamic probe is an effective tool used in site investigation. it is more economic than the use of direct drilling, particularly in explorations with moderate depth. this paper presents an experimental study to investigate the capability of using dynamic probing to evaluate the shear strength and compaction percent of fine soil. a series of dynamic probe tests were carried out at 6 differen...

conclusions the aspirates from the hypovascular and hypervascular sites of solid nodules are complementary and should be performed consecutively. results when only hypervascular site was used, adequate sampling was limited to 65% of the cases. when both sites were evaluated together, overall adequate sampling was 91%. adding a sample from the hypervascular site to hypovascular aspirate increase...

conclusions for the first time to our knowledge, we have reported a severe retropharyngeal and upper mediastinum cellulitis, probably due to the fna procedure in an immunocompetent young woman. case presentation a thirty-five-year-old female was admitted to hospital with hoarseness, laryngeal stridor and dyspnea without fever that emerged about 3 days after a first diagnostic fna. after the pro...