Sediment cores collected from eight lakes along the western coast of Svalbard as part of a project investigating atmospheric pollution and environmental change in Arctic regions were dated radiometrically using natural (Pb) and artificial (Cs and Am) fallout radionuclides. At four sites the sedimentation rates were relatively uniform, and in consequence the Pb dates were relatively unambiguous....

In this research, by a simple and modified method, nanoporous of Ni(II) ion loaded Y-type zeolite (NNZ) was designed and applied as a novel highly efficient catalyst for the synthesis of quinoxalines, pyrido[2,3-b]pyrazines, and indolo[2,3-b]quinoxalines 3a-s. These heterocycles were obtained through a one-pot condensation reaction of aryl-1,2-diamines with 1,2-dik...

Mesoporous aggregates of nanocrystalline zeolites with MFI and BEA frameworks have been synthesized using a one-pot and single structure directing agent. The effect of different reaction conditions, such as temperature, time, pH and water content, on the particle size, surface area and mesopore volume has been studied. Nanocrystalline and mesoporous ZSM-5, β and Y zeolites were modified with di...

A systematic study of two-staged upgrading process of vacuum residue for light fuel production has been carried out in a semi-batch binary reactor apparatus over Y, ZSM-5 and alkaline treated ZSM-5 zeolites. Prepared catalyst samples were characterized with XRD and BET. Density and Viscosity physical properties parameters estimation, as well as GC/SIMDIS analyses were conducted on liquid produc...

Bio-oil produced from conventional flash pyrolysis has poor quality and requires expensive upgrading before it can be used as a transportation fuel. In this work, a high quality bio-oil has been produced using a novel approach where flash pyrolysis, catalysis and fractionation of pyrolysis vapors using two stage condensation are combined in a single process unit. A bench scale unit of 1 kg/h fe...

Adoption of new management techniques that improve soil water storage and soil N plant availability yet limit N leaching may help improve environmental quality. A benchtop study was conducted to determine the influence of a single urea fertilizer rate (224 kg N ha) applied with band or fully mixed zeolite (clinoptilolite) application rates (up to 90 Mg ha) on NH4-N and NO3-N concentrations in a...

OBJECTIVES In this research, zeolite X and zeolite Y were used as vehicle to prepare intestine targeted oral delivery systems of indomethacin and ibuprofen. MATERIALS AND METHODS A soaking procedure was implemented to encapsulate indomethacin or ibuprofen within synthetic zeolites. Gravimetric methods and IR spectra of prepared formulations were used to assess drug loading efficiencies into z...

Article type: Original article Objective(s): In this research, zeolite X and zeolite Y were used as vehicle to prepare intestine targeted oral delivery systems of indomethacin and ibuprofen. Materials and Methods: A soaking procedure was implemented to encapsulate indomethacin or ibuprofen within synthetic zeolites. Gravimetric methods and IR spectra of prepared formulations were used to assess...

Luminescent zeolites exchanged with two distinct and interacted emissive ions are vital but less-studied for the potential applications in white light emitting diodes, solar cells, optical codes, biomedicine and so on. Typical transition metal ion Mn2+ and lanthanide ion Yb3+ are adopted as a case study via their characteristic transitions and the interaction between them. The option is conside...