This contribution deals with new geology, petrography, and bulk-rock/mineral chemistry of the poorly studied ultramafics Wadi Ibib–Wadi Shani (WI–WS) district, South Eastern Desert, Egypt. These are dismembered ophiolitic rocks that can be subdivided into serpentinites serpentinized peridotites. Primary minerals such as olivine pyroxene absent in serpentinites, but relics them occur Pseudomorph...

Fe-Cr alloy layers on Fe 001 substrates with different atomic environments are theoretically investigated through a self-consistent real-space tight-binding method parametrized to density functional theory and without collinear restriction for the spin directions. We show that the intermixing at the Cr/Fe interface, experimentally observed at the first stages of the Cr growth on Fe, originates ...

ةیتوبكنعلا ةكبشلا و ينورتكللإا ثدحتلا و دیربلا لثم ةددعتملا اھتامدخب تینرتنلإا ةكبش ربتعت لا تامولعملا لدابت و لقنل ةیلاعف رثكلأا ةقیرط . يتلا تایوتحملاب ةمحدزم تدغ ةكبشلا هذھ نأ لاإ امداصت تببس " احضاو " امداصت لب اندیلاقت و انتاداع عم " نوناقلا عم . ةلیلق و ةئیذبلا عقاوملا ةیرصنعلا و ةیھاركلا ىلع عجشت يتلا عقاوملا و ةیحابلإا تایوتحملا تاذ ماشتحلاا لاإ تسیل يھ لافطلأا مھنمض نم و تینرتنلإا ةكبش...

The slurry erosion behaviour of laser clad Fe–Cr–B–Si alloy coatings was investigated at impact angles from 30u to 90u with an increment of 15u, and compared with the slurry erosion behaviour of two laser clad carbide coatings and a non-coated substrate made of AISI 4140 steel. The Fe–Cr–B–Si alloy coatings had slurry erosion resistance. Their overall slurry erosion resistance at impact angles ...

کچ ی هد هکبش هکبش رگسح یاه رگسح زا یا هنیزه مک و دودمح یژرنا اب ،کچوک یاه دنتسه یا یم شخپ رظن دروم هقطنم رد هک هداد ات دنوش عجم طیمح زا ار ییاه شزادرپ یارب و هدونم یروآ یزکرم هرگ هب ١ دننک لاسرا . م نینچهم ی هب و هداد صیخشت طیمح رد ار یدادخر عوقو دنناوت دنناسرب یزکرم هرگ علاطا . هکبش هنوگنیا ریخا یالهاس رد هنیمز رد اه یاهدربراک فلتمخ یاه هدرک ادیپ یدایز دنا . زا دنترابع اهدربراک نیا هلجم زا...

The microstructures of chromium and iron borides formed during laser surface alloying of AISI 1045 steel with CrB were examined by transmission electron microscopy combined with selected-area electron diffraction and X-ray-dispersive spectroscopy. It was found that the heavily faulted (Cr, Fe)2B phase contains a microsyntactic existence of several polytypes, including one-dimensionally disorder...

This work investigated the effect of co-existing organic matters on aqueous Cr(VI) reduction by electrodeposited zero-valent iron (ED Fe(0)) at neutral pH. The ED Fe(0) prepared in a solution containing mixture of saccharin, L-ascorbic acid and sodium dodecyl sulfate showed higher activity in reducing the aqueous Cr(VI) at neutral pH than that prepared without any organic presence. XRD and SEM ...

Ferritin concentrates iron as a hydrous ferric oxide in a protein cavity (8 nm in diameter) by using eight pores along the threefold symmetry axes of the octahedral supramolecular structure. The role of ligand exchange in the entry of Fe(II) hexahydrate into ferritin protein has been studied with [Cr(TREN)(H2O)(OH)] [TREN N(CH2CH2NH2)3], a model for Fe(H2O)6 with only two exchangeable ligands. ...

The mechanisms of photo-catalytic reduction of Cr(VI) were investigated in acidic solutions with and without Fe(III). In a system without Fe(III), no Cr(VI) reduction was observed in dark conditions; conversely, under light conditions, the reduction reaction rate increased to 0.011 and 0.020microM min(-1) at pH 2 and pH 1, respectively, indicating the occurrence of Cr(VI) photo-reduction. The C...