In this study, carbon-silica based acid catalysts derived from rice husks (RH) were successfully synthesised using microwave (MW) technology. The results showed that MW sulphonation produced Sulphur (S) content of 17.2–18.5 times higher than in raw RH. Fourier-transform Infrared Spectroscopy (FTIR) peak at 1035 cm?1 which corresponded to O?S?O stretching sulphonic (-SO3H) group. XRD sulfonated ...

The interaction of hydrogen with Pd-SiO2 interfaces has been investigated for the first time using first-principles calculations based on density functional theory. The hydrogen-induced polarization at the Pd-SiO2 interfaces was evaluated using Pd-SiO2 interface supercells. As a result, the potential change induced by interfacial hydrogen atoms was not observed even for hydrogen concentration o...

1 pi − 2 j+1 > 7pr − 4pr > pr . If r is odd, set nk = ∏r1 pi − 2k+1. Then nk ≡ 3(4) (since 32 ≡ 1(4)). But no pi divides nk for 1 ≤ i ≤ r , so the integer nk has some prime factor qk ≡ 3(4) with qk > pr . If j = k, say j > k, the assumption that qk also divides n j leads to the same contradiction as earlier: since nk − n j = 2 j+1 − 2k+1 = 2k+1(2 j−k − 1), we have qk | 2 j−k − 1 and hence qk < ...

Kaolin-SO3H as a new solid acid is prepared via reaction of kaolin and chlorosulfonic acid. This natural based catalyst is very inexpensive and easy available. Imidazoles are an important class of heterocycles being the core fragment of different natural products and biological systems such as anti-allergic, anti-inflammatory, analgesic, antifungal, antimycotic, antibiotic, antiulcerative, anti...

Introduction In recent years, there has been an increasing interest in silica (SiO2) nanoparticles (NPs) as drug delivery systems. This interest is mainly attributed to the ease of their surface functionalization for drug loading. In orthopedic applications, gentamicin-loaded SiO2 NPs (nanohybrids) are frequently utilized for their prolonged antibacterial effects. Therefore, the possible advers...

BACKGROUND SiO2 nanoparticle is one of the most popular nanomaterial which has been used in various fields, such as wastewater treatment, environmental remediation, food processing, industrial and household applications, biomedicine, disease labeling, and biosensor, etc. In agriculture, the use of SiO2 nanoparticles as insecticide, carriers in drug delivery, or in uptake and translocation of nu...

a general synthetic route for the synthesis of 1,2-dihydro-1-aryl-naphtho[1,2-e][1,3]oxazine-3-one derivatives has been developed using perlite-so3h nanoparticles as efficient catalyst under both microwave-assisted and thermal solvent-free conditions. the combination of 2-naphthol, aldehyde and urea enabled the synthesis of 1,2-dihydro-1-aryl-naphtho[1,2-e][1,3]oxazine-3-one derivatives in the ...