RESUMEN
A large-scale quantity of copper oxalate nanoparticles were successfully obtained via a facile and green solid-state chemical reaction. Copper oxalate nanoparticles were obtained by ball-milling between copper chloride, Liquorice (Glycyrrhiza glabra), and ascorbic acid at ambient conditions. The size and morphology of copper oxalate nanoparticles powder were studied by transmission and scanning electron microscopy. The prepared nanoparticles were semi-spherical in shape and ranged from 5 to 15â nm in size. UV/Vis spectroscopy, Fourier transforms infrared spectroscopy, and X-ray photoelectron spectroscopy measurements were carried out to characterize the prepared samples. Copper oxalate nanoparticles were evaluated as a catalyst in the catalytic degradation of 4-nitrophenol, bromophenol blue, reactive yellow, and a mixture of the three pollutants. The present study combined solid-state reaction and green requirements for the mass production of nanomaterials. The proposed reaction is performed in simple steps, inexpensive, low energy consuming, solvent-free, and minimizes the emission of secondary wastes.
Asunto(s)
Glycyrrhiza , Nanopartículas , Cobre/química , Nanopartículas/química , Ácido Ascórbico , Oxalatos , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Twenty three cases of thymectomy were performed in Bangabandhu Sheikh Mujib Medical University (BSMMU) from 2004-2006 for myasthenia gravis, age ranging from 18 to 65 years, male were 16 and female 07. Out of these cases 09 had thymoma of which 03 have shown features of malignancy. There was no pre-operative or post operative mortality. Thymectomy in myasthenia gravis was considered when there was clinical feature of drooping eye lids, difficulty in deglutition, nasal voice, generalized weakness etc. All patients received medical treatment before and after surgery. Medical treatment usually given at BSMMU anticholinesterase such as mastinon, if the patient is improved and well tolerated, this regime is continued. Although, role of steroid and immunosuppressive agents for the treatment of myasthenia gravis is controversial, steroid used in few cases of type II & type III. No steroid used in ocular variety. Patients were followed for one year and showed significant improvement after surgery.
Asunto(s)
Miastenia Gravis/cirugía , Timectomía , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
Poly(vinylalcohol) (PVA)/vanadium pentoxide xerogel (VXG) composites were prepared and exposed to different electron beam irradiation doses. Changes in the structural properties, crystallinity degree of composites with increasing irradiation doses and VXG content were subsequently investigated using the Fourier transformer infrared spectroscopy (FTIR), X-ray diffraction (XRD), and differential scanning calorimetry (DSC) techniques. The crystallinity degree of the PVA matrix was found to decrease markedly due to VXG addition and/or irradiation process.