Approximately 1% of presolar SiC grains found in primitive meteorites condensed in the ejecta of Type II supernovae. To explain the isotopic signatures of these so-called X grains, material from different SN zones had to contribute to the mix from which the grains formed. We measured the Fe and Ni isotopic ratios of individual X grains with the NanoSIMS. Most grains have enhanced 57 Fe/ 56 Fe r...

Effects of ultra high magnetic field of both pulse and steady types on martensitic transformation have been studied, using Fe-Ni-Mn, Fe-Ni-Mn-C alloys with the supplemental tests on Fe-Ni-C and Fe-NiCo-Ti alloys. It is found that the martensitic transformation is induced at room temperature not only athermally but also isothermally either by pulse magnetic field or by steady magnetic field for ...

The influence of composition and purity of titanium on the mechanical properties and the transformation temperatures of Ni-Ti alloy dental castings was investigated by tensile testing and differential scanning calorimetry (DSC). The compositions of the ingots were 49.0-49.2 at% of titanium content. Three grades of titanium of relatively high purity were used as starting materials. The result sh...

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Uptake hydrogenase is an enzyme that is beneficial for nitrogen fixation in bacteria. Recent studies have shown that Frankia sp. has two sets of uptake hydrogenase genes, organized in synton 1 and synton 2. In the present study, phylogenetic analysis of the structural subunits of hydrogenase syntons 1 and 2 showed a distinct clustering pattern between the proteins of Frankia strains that were i...

در این مقاله حل دقیق ارتعاش برون صفحه‌ای نانو ورق‌های مستطیلی نسبتاً ضخیم براساس تئوری غیر‌محلی تغییر شکل برشی سینوسی اصلاح شده با نظر گرفتن شرایط مرزی لوی ارائه است. هدف اصلی تحقیق بررسی اثر مقیاس کوچک بر پارامترهای فرکانسی می‌باشد. برای توصیف تأثیرات خارج از صفحه‌ی ورق غیر محلی ارینگن استفاده شده. مشتمل شش حالت مختلف شامل دو ضلع موازی دارای تکیه‌گاه ‌ساده و اضلاع دیگر ترکیبی ساده، گیردار آزاد ...