Search results for "Sem micrographs"
showing 6 items of 6 documents
Accuracy combining different brands of implants and abutments
2013
Objective: To evaluate the vertical misfit between different brands of dental implants and prosthetic abutments, with or without mechanical torque, and to study their possible combination. Study design: Five different brands of implant were used in the study: Biofit (Castemaggiore, Italy), Bioner S.A. (Barcelona, Spain), 3i Biomet (Palm Beach, U.S.A.), BTI (Alava, Spain) and Nobel Biocare (Göteborg, Sweden), with standard 4.1 mm heads and external hexagons, and their respective machined prosthetic abutments. The implant-to- abutment fit/misfit was evaluated at four points (vestibular, lingual/palatine, mesial and distal) between implants and abutments of the same brand and different brands,…
Use of positron annihilation measurements to detect the defect beneath worn surface of stainless steel 1.4301 (EN) under dry sliding condition
2012
Abstract Positron measurements were performed for detection of the subsurface zone in the stainless steel 1.4301 (EN) exposed to dry sliding. They revealed the defect profile induced by dry sliding which is extended inward the worn surface from 85 μm to 400 μm depending on the applied load during the tribo-test. This result was obtained using the positron techniques, while the microhardness profile exhibited shorter range of the microhardness depth profile, i.e., from 70 μm to 150 μm. However, at the depth of about 5 μm from the worn surface the sudden increase in the microhardness was observed. The complementary measurements of X-ray diffraction and SEM micrographs of the worn surface were…
Electrodeposition of CeO2 and Co-Doped CeO2 Nanotubes by Cyclic Anodization in Porous Alumina Membranes
2013
An anodic electrodeposition process is proposed to prepare CeO2 and Co-doped CeO2 nanotubes. Anodic alumina membrane is used as template and linear sweep voltammetry is employed to allow the formation of nanotubes without alumina dissolution. SEM micrographs showed large arrays of well defined and aligned NTs, which resulted to be crystalline soon after deposition according to XRD diffraction patterns and Raman Spectroscopy.
Unisexual flowers as a robust synapomorphy in Cariceae (Cyperaceae)? Evidence for bisexual flowers in Schoenoxiphium
2012
Abstract Cariceae, the largest tribe within Cyperaceae, comprises about 2000 species in five genera. Cariceae is usually considered to be distinct from other Cyperaceae by the presence of exclusively unisexual flowers and by the arrangement of the pistillate flowers in single-flowered spikelets that are enclosed by the flask-like spikelet prophyll (utricle or perigynium). The nature of several morphological features of the Cariceae inflorescence remains controversial. The staminate reproductive units, as well as earlier reported bisexual reproductive units in Schoenoxiphium have been considered to be reduced partial inflorescences, or flowers. Aims of this study are to test both interpretat…
Mechanical properties of recycled polyethylene ecocomposites filled with natural organic fillers
2006
The use of natural organic fillers in addition to postconsumer recycled polymers is getting a growing interest during the last years; this is due to many advantages they can provide in terms of cost, aesthetic properties, environmental impact. In this work, several types of wood flour (differing each other with regard to production source and particle size) were added to a recycled polyethylene coming from films for greenhouses and the effects of filler type, content, and size were investigated. Investigation was then focused on the improvement of mechanical properties, through the addition of polar copolymers (ethylene-co-acrylic acid, ethylene-vinyl acetate) and a maleic anhydride-grafted…
MORPHOLOGICAL OBSERVATIONS ONCYCLOTELLA DISTINGUENDAHUSTEDT ANDC. DELICATULAHUSTEDT FROM THE CORE SAMPLE OF A MEROMICTIC KARSTIC LAKE OF SPAIN (LAKE …
2007
Two Cyclotella species were found during the electron microscopic investigation of core samples from Lake La Cruz. Cyclotella distinguenda Hustedt was subdominant in the layers 80-110 cms and C. delicatula Hustedt was frequent and abundant in the layers 20-180 cms. SEM studies revealed an interesting variation in their valve structure elements. Analyses of the morphological characteristics of these species on the basis of SEM micrographs (55 photos were taken from C. distinguenda and 95 from C. delicatula) was made it possible to complete their description. In this paper, the similarities and differences between Cyclotella distinguenda, C. delicatula and related taxa (Cyclotella azigzensis …