Search results for "RADIATION"

Scanning from heating: 3D shape estimation of transparent objects from local surface heating.

2009

Today, with quality becoming increasingly important, each product requires three-dimensional in-line quality control. On the other hand, the 3D reconstruction of transparent objects is a very difficult problem in computer vision due to transparency and specularity of the surface. This paper proposes a new method, called Scanning From Heating (SFH), to determine the surface shape of transparent objects using laser surface heating and thermal imaging. Furthermore, the application to transparent glass is discussed and results on different surface shapes are presented.

Influence of surface morphology on melting of polymer crystals II. Loops of random length and partially random reentry

1972

Abstract The melting behavior of single crystals with loops of random length and partially random reentry has been calculated under two different assumptions: (1) at each temperature the loops have an equilibrium end-to-end distance distribution and (2) a certain end-to-end distance distribution of the loops, ω(h), determined by the kinetics of the crystallization is frozen in and maintained during the whole heating process. The ω(h) is calculated by considering the loop formation process during crystallization and by introducing a parameter λ which expresses the tendency of the chains for adjacent reentry. In both cases a melting range is obtained. In case 2, the melting range depends stro…

Molecular Dynamics Study of Disordering and Premelting of the Pb(110) Surface

1994

Molecular dynamics simulations incorporating a many-body (glue) potential have been used to investigate the atomic structure and dynamics of the Pb(110) surface in the range from room temperature up to the bulk melting point. The Pb (110) surface starts to disorder approximately at 360 K via the generation of vacancies and the formation of an adlayer. At about 520 K we observe the onset of a quasiliquid region at the surface, which exhibits liquid-like energetic, structural and surface properties. The disordering is enhanced in the direction parallel to the close-packed rows. While losing long range order, the two outermost quasiliquid layers retain a considerable degree of short range orde…

A new liquid surface neutron reflectometer and its application to the study of DPPC in a monolayer at the air/water interface

1991

A constant wavelength neutron reflectometer is described. Using this reflectometer, the neutron reflectivities from phosphatidylcholine monolayers in the highly condensed LC phase on ultra pure H2O and D2O have been measured on a Wilhelmy film balance. The neutron reflectivities have been carefully compared with those obtained by the X-ray method applied to the same monolayer under similar conditions. A new approach to analyzing a combined set of data composed of X-ray and neutron reflectivities has been used. From the analysis it is concluded that despite their limited qz range neutron reflectivities are as essential as X-ray reflectivities for the unique determination of the monolayer str…

Experimental and theoretical evidence of overcharging of calcium silicate hydrate

2007

International audience; Electrokinetic measurements such as electrophoresis may show an inversion of the effective surface charge of colloidal particle called overcharging. This phenomenon has been studied by various theoretical approaches but up to now very few attempts of confrontation between theory and experiment have been conducted. In this work we report electrophoretic measurements as well as Monte Carlo simulations of the electrokinetic potential for the surface of calcium silicate hydrate (Csingle bondSsingle bondH), which is the major constituent of hydrated cement. In the simulations, the surface charge of Csingle bondSsingle bondH nanoparticles in equilibrium with the ionic solu…

Effects of Ultraviolet Photoactivation on Osseointegration of Commercial Pure Titanium Dental Implant After 8 Weeks in a Rabbit Model

2020

This study investigated whether a 6-Watt ultraviolet C-lamp was capable of producing photofunctionalization on commercial implants during a medium observation term of 8 weeks. A total of 20 implants were inserted in 5 New Zealand rabbits, with each animal receiving 2 implants per tibia (one photofunctionalized and one untreated), according to a previously established randomization sequence. All implants were inserted by a single surgeon following the manufacturer's instructions. Histological analysis was performed by an evaluator who was blinded to the treatment condition. After 8 weeks of healing, the 2 groups showed no statistically significant differences in terms of bone-to-implant cont…

Role of Diffusion in Superplasticity and Brittleness of Fine-Grained Binary Eutectics

2005

Mechanical properties of interphase boundaries (IB), stability of defects and microstructure in heavily deformed binary eutectics (Al-Sn, Zn-Sn, Pb-Sn, Cd-Sn, Bi-Sn) have been investigated at room temperature. Experiments were carried out on atomically clean surfaces of alloys and on bimetallic joints with clean interface. It has been shown that after severe deformation the phases are strengthened and relaxation processes occur mainly on the boundaries in all eutectics. For superplastic eutectics with low interphase boundary energy the intensive development of the diffusion – controlled processes of self- healing, sintering, segregation and enveloping were observed. These diffusion processe…

Interface Diffusion Controlled Sintering of Atomically Clean Surfaces of Metals

2003

Effects of organic aerosol constituents on extinction and absorption coefficients and liquid water contents of fogs and clouds

1978

We have speculated on the influence of organic material on extinction and absorption coefficients and liquid water content of fogs and of clouds immediately after their condensational stage. It results therefore, that the reduction of the speed of growth from fog to cloud droplets due to the presence of organic films largely reduces the properties mentioned. Compared to that their increase coming from the surface tension reduction due to organic material being dissolved or building up films is expected to be less effective.

Adaptive radiation along a thermal gradient: preliminary results of habitat use and respiration rate divergence among whitefish morphs.

2014

Adaptive radiation is considered an important mechanism for the development of new species, but very little is known about the role of thermal adaptation during this process. Such adaptation should be especially important in poikilothermic animals that are often subjected to pronounced seasonal temperature variation that directly affects metabolic function. We conducted a preliminary study of individual lifetime thermal habitat use and respiration rates of four whitefish (Coregonus lavaretus (L.)) morphs (two pelagic, one littoral and one profundal) using stable carbon and oxygen isotope values of otolith carbonate. These morphs, two of which utilized pelagic habitats, one littoral and one …