Effect of Characteristics of Si3N4 Powder on Sintering behavior of Si3N4-AlN-Y2O3 System.

Effect of Nano-TiN on Mechanical Behavior of Si3N4 Based Nanocomposites by Spark Plasma Sintering (SPS)

effect of oral presentation on development of l2 learners grammar

this experimental study has been conducted to test the effect of oral presentation on the development of l2 learners grammar. but this oral presentation is not merely a deductive instruction of grammatical points, in this presentation two hypotheses of krashen (input and low filter hypotheses), stevicks viewpoints on grammar explanation and correction and widdowsons opinion on limited use of l1...

the effect of explicit teaching of metacognitive vocabulary learning strategies on recall and retention of idioms

چکیده ندارد.

Pressureless Sintering of Si3N4 Ceramic Using AlN and Rare-Earth Oxides

Using intermediate, liquid-forming compositions in the approach focuses on the Si3N4–R2O3 binary, where R2O3 is any (Y,La)2O3–AlN system as additives, fully dense Si3N4 ceramrare-earth oxide (or Y2O3) used singly or severally. After sinics with high strength at high temperature have been tering, this composition forms -Si3N4 and some refractory rareobtained by pressureless sintering. The cerami...

In-situ reactive synthesis of full dense Si2N2O by incorporating of Amourphous nanosized Si3N4;effect of MgO and Y2O3

Si2N2O is considered as a new great potential structural/functional candidate in place of Si3N4. The amorphous Si3N4 nanopowder was incorporated into silica sol by adding of MgO and Y2O3 as sintering aid. Synthesized powders were heated by spark plasma sintering at a heating rate of 100 oC/min yielded fully dense compacts at 1550 and 1750 oC for 40 min. The phase formation of samples was charac...