we evaluated the effect of fe/alumina catalyst contained different cadmium contents and two synthesis temperatures on producing carbon nanotubes by chemical vapor deposition of methane as a feedstock.  x-ray powder diffraction (xrd), n2 adsorption-desorption, scanning electron microscopy (sem), transmission electron microscopy (tem), raman spectroscopy and thermogravimetry analysis (tga) were u...

highly self-ordered alumina nanopore arrays were fabricated using hard anodization technique in different mixtures of oxalic/phosphoric acid. the phosphoric acid concentration was varied from 0.05 to 0.3 m while the oxalic acid concentration was changed between 0.3 and 0.4 m. the self ordered nanoporous arrays were obtained in anodization voltage changing from 130 to 200 v. the interpore distan...

– the normal and lateral line cycloid scales of a cyprinid fish capoeta damascina (valenciennes incuvier and valenciennes, 1842) have been subjected to the scanning electron microscopy technique in orderto study their detailed structure. the scales have the general morphological characteristics of the cycloidscales. in the normal scale located below the dorsal fin, the focus lies towards the an...

introduction the aim of this study was to compare the smear layer removal efficacies of 3% sodium hypochlorite (naocl), 17% ethylenediaminetetraacetic acid (edta), smearclear and biopure mtad using a common irrigation protocol. materials and methods: fifty freshly extracted human single rooted maxillary and mandibular teeth were prepared by a protaper rotary system up to an apical preparation f...

this study compared the marginal adaptation of mineral trioxide aggregate (mta) and mta-like materials as root-end fillings after incubation in phosphate buffer saline (pbs), a synthetic tissue fluid, for either 1 week or 2 months.in this experimental study, seventy-two extracted human single-rooted teeth were prepared and obturated with gutta-percha and ah26 sealer. the apical 3 mm of the root...

introdouction: dentinal hypersensitivity (dh) is one of the most painful chronic problems reported in dental offices. various methods have been applied for the treatment of dh. however, majority of them are either ineffective or last for a short period of time. it has been reported that lasers, particularly neodymium- doped: yttrium aluminum garnet laser (nd: yag), can be helpful in the treatme...

while a wide array of pathological changes occur in cerebral arteries following subarachnoid hemorrhage (sah), the most consistent is endothelial damage. since the endothelium normally modulates reflexes that influence vascular tone, any damage to it may represent a significant contributor to cerebral vasospasm following sah. this experimental study investigates the correlation between endothel...

A scanning electron microscopy (SEM) and transmission electron microscopy (TEM) study was made of lesions from acute, experimentally induced cases of jaagsiekte. In the SEM study tumour cells were easily identified by the abundant microvilli on their peripheral surface. The SEM study gave further insight into the development of lesions and the spatial relationship of cells involved in jaagsiekt...

Despite being an excellent tool for investigating ultrastructure, scanning electron microscopy (SEM) is less frequently used than transmission electron microscopy for microbes such as viruses or bacteria. Here we describe rapid methods that allow SEM imaging of fully hydrated, unfixed microbes without using conventional sample preparation methods. We demonstrate improved ultrastructural preserv...

The intracellular morphogenesis of flaviviruses has been well described, but flavivirus release from the host cell remains poorly documented. We took advantage of the optimized production of an attenuated chimeric yellow fever/dengue virus for vaccine purposes to study this phenomenon by microscopic approaches. Scanning electron microscopy (SEM) showed the release of numerous viral particles at...