Search results for "scanning"

Marginal integrity of class V restorations: SEM versus dye penetration.

2006

To perform an in vitro investigation on the marginal integrity of different adhesives (Optibond FL, Scotchbond 1XT, Clearfil SE Bond, Adper Prompt L-Pop, S(3) Bond, iBond exp., Adper Prompt L-Pop) in combination with Tetric Ceram as well as an experimental silorane-restorative (Hermes, Hermes Bond; 3M ESPE) using SEM and dye penetration (2% methylene blue) in a comparative manner.Standardized class V-cavities (3 mm x 1.5 mm) were prepared in 70 extracted human teeth (n=10). The adhesives were applied according to manufacturers' instructions. The cavities were restored with three increments. After finishing and polishing (Sof-Lex discs) and thermocycling (5000x, 5/55 degrees C), replicas wer…

Surface debris of canal walls after post space preparation in endodontically treated teeth: A scanning electron microscopic study

2004

Abstract Purpose To evaluate surface cleanliness of root canal walls along post space after endodontic treatment using 2 different irrigant regimens, obturation techniques, and post space preparation for adhesive bonding. Study design Forty teeth, divided into 4 groups, were instrumented, using Ni-Ti rotary files, irrigated with NaOCl or NaOCl + EDTA and obturated with cold lateral condensation (CLC) or warm vertical condensation (WVC) of gutta-percha. After post space preparation, etching, and washing procedure, canal walls were observed using a scanning electron microscope (SEM). Amount of debris, smear layer, sealer/gutta-percha remnants, and visibility of open tubules were rated. Result…

Environmental accounting as a tool for SMEs in environmentally induced economic risk analysis

2000

Assessing environmental performance trends in the transport industry: Eco-innovation or catching-up?

2015

Abstract This paper analyses the change in environmental performance that took place in the transport industry of 38 countries between the years 1995 and 2009. Data Envelopment Analysis techniques and directional distance functions are employed to compute Luenberger productivity indicators for the change in environmental performance and its determinants, namely, environmental technical change resulting from eco-innovation and catching-up with best available environmental technologies. Eight air pollutants account for the environmental contaminants from transport activities, and these are aggregated into three main categories of environmental pressures, namely, global warming, tropospheric o…

Processes during preparation of lead/acid battery positive plates from tetrabasic lead sulfate (4BS) pastes

1993

Abstract Tthe processes studied during this investigation were paste mixing and curing. Tetrabasic lead sulfate 4BS pastes were prepared by solution and paste methods both from α-PbO and mill oxides, and the development of 4BS was carried out already during the paste mixing stage. the 4BS pastes were characterized by SEM, TEM, XRD and wet-chemical methods, and the results were compared with those obtained from the characterization of corresponding tribasic lead sulfate (3BS) pastes. The preparation method was found to be one dominating factor affecting both the morphology and structure of 4BS active masses. The selection of raw material gave an additional effect on the morphology. Additiona…

An impedance study of complex Al/Cu-Al2O3electrode

2011

Electrochemical impedance spectroscopy (EIS) was used to investigate different Cu deposition regimes on Al surface obtained by internal electrolysis and to characterize properties of fabricated electrodes. EIS experimental data confirmed that Cu deposition by internal electrolysis is realized and the complex electrode system is obtained. The main difficulty in preparation of Al/Cu electrodes is to prevent aluminium oxidation before and during electrochemical deposition of Cu particles. In this work NaCl, CH3COONa, K2SO4, mono- and diammonium citrate electrolytes were examined to determine their suitability for impedance measurements. Al/Cu-Al2O3 electrode composition was approved by equival…

Study of the Growth Mechanism of some Oxide Scales on Alloy 230 in High Temperature Vapor Electrolysis (HTVE) Conditions

2012

Alloy 230 (also named Haynes® 230) was tested as interconnect for production of hydrogen via High Temperature Vapor Electrolysis (HTVE). Samples were oxidized at 800°C in the both atmospheres representative of the HTVE operating conditions: Ar-1%H2-9%H2O (for cathode side) and air (for anode side). The high temperature oxidation behaviour was studied in both atmospheres together with the electrical conductivity of the thermally grown oxide scales. Oxidation kinetics indicated lower oxidation rate in H2/H2O compared to air (kp = 3.8 .10-15 g2.cm-4.s-1 in H2/H2O and kp = 1.6 .10-14 g2.cm-4.s-1 in air). The corrosion products were characterized by scanning electron microscopy associated with X…

Sub-wavelength imaging of light confinement and propagation in SOI based photonic crystal devices

2006

A light source is coupled into photonic crystal devices and a near field optical probe is used to observe the electromagnetic field propagation and distribution at a sub-wavelength scale. Bloch modes are clearly observed.

Silencing and enhancement of second-harmonic generation in optical gap antennas

2012

International audience; Amplifying local electromagnetic fields by engineering optical interactions between individual constituents of an optical antenna is considered fundamental for efficient nonlinear wavelength conversion in nanometer-scale devices. In contrast to this general statement we show that high field enhancement does not necessarily lead to an optimized nonlinear activity. In particular, we demonstrate that second-harmonic responses generated at strongly interacting optical gap antennas can be significantly suppressed. Numerical simulations are confirming silencing of second-harmonic in these coupled systems despite the existence of local field amplification. We then propose a…

Computation of the field diffracted by a local surface defect: application to tip–sample interaction in the photon scanning tunneling microscope

1996

We use a method based on the Fourier transform of the electromagnetic field to compute the field diffracted by a local deformation of a plane boundary surface. We give a complete development of each step of the technique. To show the interaction that exists between the probe of a near-field optical microscope and the observed sample, we use the model of a truncated cone-shaped tip above a rectangular surface defect. We compute the electrical intensity along a line located between the tip and the local surface defect. We show the influence of the polarization of the incident wave and the effect of the position of the tip with respect to the position of the surface defect.