نتایج جستجو برای: gamma alumina γ al2o3
تعداد نتایج: 211442 فیلتر نتایج به سال:
A new rapid, very simple and one-step sol-gel strategy for the large-scale preparation of highly porous γ-Al₂O₃ is presented. The resulting mesoporous alumina materials feature high surface areas (400 m² g-1), large pore volumes (0.8 mL g-1) and the γ-Al₂O₃ phase is obtained at low temperature (500 °C). The main advantages and drawbacks of different preparations of mesoporous alumina materials ...
در این مقاله تبدیل فروکتوز به عنوان مشتقی از زیست توده به ترکیب 5-هیدروکسی تیل فورفورال با استفاده از کاتالیزور آلومینای سولفونه شده بررسی شده است. جهت تهیه کاتالیزورها، γ-Al2O3 و nano-γ-Al2O3 توسط کلرو سولفونیک اسید، سولفونه شدند. کاتالیزورهای تولید شده توسط روشهای FT-IR، TEM، SEM، BET و TGA شناسایی شد. در این پژوهش تأثیر پارامترهایی مانند نوع کاتالیزور، نوع حلال، مدت زمان واکنش و غلظت فروکتو...
two-component reaction of 2-aminobenzophenones with acetylenic esters in the presence of γ-al2o3 and cu/zno as suitable heterogeneous catalysts has been studied. nano γ-al2o3 and cu/zno showed high activities when used as surface catalysts for the synthesis of quinoline derivatives. after completion of the reaction, the catalyst was recovered and reused several times under the same reaction con...
Mesoporous gamma-alumina granules, which are known as a common catalyst support in industrial applications were synthesized via the sol gel-oil drop method having a diameter of 1-2 mm. The effect of calcination temperature (450 and 750 °C) on the properties of gamma alumina granules were studied and the functionality of 20 wt% iridium catalyst on the alumina granules for hydrazine decomposition...
یکی از مهمترین روش های تولید مواد و پوشش های اکسیدی، اکسیداسیون به روش پلاسمای الکترولیتی (PEO) است. پوشش های ایجاد شده بر روی آلومینیم در روش PEO دارای دو آلتروپی α-Al2O3 و γ-Al2O3می باشند که پوشش های حاوی آلوتروپی α-Al2O3 دارای سختی و مقاومت به سایش بهتری هستند. بنابراین هدف اصلی تحقیق حاضر بهینه سازی آلوتروپی اکسید آلومینیم در جهت افزایش مقدار α-Al2O3 در پوشش ایجاد شده به روش PEO است. در تحق...
Novel uniform single-crystal boehmite leaf-like nanosheets with high anisotropy (with a lateral size of (4.5±0.5 μm)×(9.0±1.0 μm) and a thickness of 60–90 nm) and flower-like superstructures consisting of single-crystal petals were synthesized for the first time by a simple hydrothermal method. After calcination, those boehmite structures can be transformed into single-crystal gamma-alumina nan...
In the present investigation, γ-alumina nanoparticles with particle sizes less than 10 nm, high specific surface area (351 m2/g), high pore volumes and relatively narrow pore sizes distribution was prepared via sol-gel method in presence of aluminum isopropoxide as an aluminum precursor, distilled water, acetic acid as hydrolysis rate controller and tert-butanol as solvent. They had meso ...
Abstract Introduction:Fluoride is one of the essential elements for human health and presence of its acceptable value prevents from tooth decay but excessive absorption of fluorine into the body cause many chronic problems such as flourosis. The aim of this study was to evaluate the effect of &alpha-Alumina and &gamma -Alumina on removal of fluoride from water. Methods: This experimental ...
Lithium ion conductors 5. Lithium Nitride Li3N 6. Lithium Lanthanum Titanium Oxide, Li3xLa0.67-xTiO3 7. Lithium Titanium Phosphate, LiTi2(PO4)3 Sodium ion conductors 8. Sodium β-Alumina, Na2O)1+x(Al2O3)11 9. Sodium β”-Alumina, Li-stabilized, Na1.5(Li0.25Al10.75)O17 10. Sodium β-Gallate, (Na2O)*n(Ga2O3) 11. Sodium β”-Gallate, Na1.98Ga10.673 O17 12. Sodium Yttrium Silicate, Na5YSi4O12 13. Sodium ...
The wear resistance of Al2O3/2.5 vol.% Ni nanocomposites sintered by a conventional route was studied under ball-on-disk dry sliding conditions and compared with the same nanocomposites but consolidated by spark plasma sintering, together with alumina obtained by the same technique and by hot pressing. The results showed an improvement of about 0.5, 1 and 2 orders of magnitude, respectively. Th...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید