The chromium doped spinel crystals, MgAl2O4:Cr3+, have been grown using floating zone technique and its application for the fiber-optic thermometer is discussed on basis of temperature dependence fluorescence lifetime. Lifetimes crystals (τ=10 ms), which decrease with temperature, were about 3 times larger than that ruby (τ=4 ms) at room temperature. Temperature coefficients photoluminescence (PL) lifetimes (37 μs/K) are also longer (10 μs/K). potentially useful sensor probes thermometer, an...

Ruby single crystals have been grown successfully from the melt droplet on sapphire crystal fibers as sensor head directly coupled with optical fiber for thermometer applications using fluorescence decay. In this fabrication process, droplets of slurry ruby powders are formed end and dried, sintered, then melted solidified in a floating-zone furnace. The photoluminescence (PL) lifetime varies τ=3.8 to 2.5 ms Cr3+ concentrations 0.07 1.0 at. %. concentration 0.35 % is found be most suitable...

Cr-doped YAlO3 phosphor crystals have been grown and characterized for applications in fiber-optic thermometers based on the temperature dependence of photoluminescence (PL) lifetime. PL peaking at λ=735 nm is observed from following an excitation by a light-emitting diode λ=520 nm. Long lifetime (τ=43.14 ms) room as compared with those ruby (τ=4.2 spinel (τ=8.0 ms). The coefficient (−0.075 ms/K) also larger than (−0.010 or (−0.037 ms/K). considered to be sensitive sensor head material...

Long duration phosphorescent SrAl2O4 phosphors doped with various auxiliary activators (Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) have been evaluated for the fiber-optic thermometer application. In this thermometer, temperature was measured based on dependence of lifetime and/or intensity afterglow phosphorescence which dominated by thermal excitation trapped carriers. Characteristics long are quite different from those conventional using fluorescent phosphors. Lifetime...

A fiber-optic thermometer is developed based on the temperature dependence of afterglow phosphorescence intensity which dominated by thermal excitation trapped carriers using long duration phosphor, The from phosphorescent sensor head increases greatly and linearly with ranging 270 to 320 K coefficient 1.3 % K−1. materials are potentially useful phosphors for sensitive in thermometers. © 2002 Electrochemical Society. All rights reserved.

A fibre-optic thermometer using newly developed phosphor sensor materials is described. highly sensitive fluorescence chromium ion (Cr3+) doped crystals with a longer lifetime than that of conventional ruby sensors. Long fluorescent europium strontium aluminate phosphors co-doped various auxiliary activators (SrAl2O4:Eu2+, Ln3+, Ln = Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu), were also grown and evaluated. In the Cr3+ phosphor, PL decreased at temperatures ranging from 270 K to...

It is well known that the self-aligning torque decreases before lateral force saturated. Focusing on this change, an estimation method has been developed to detect friction condition between steered wheels and road surface reaches limit. The grip margin (LGM) defined based which obtained using EPS motor current information. LGM theoretically analyzed tire model experimentally verified through full-scale vehicle test. Moreover, estimated applied for chassis control systems improve dynamics...

Optical back-scattering from milk with various fat and protein concentrations were evaluated in a configuration using white, violet, blue, green, red or near infrared (NIR, λ = 850 940 nm) LEDs as the light source. The tip of optical fibre bundle was dipped into 8.2 to 39 g L−1 32 37.7 L−1, respectively. intensities varied linearly milk. slope (G) calibration lines wavelength incident light. G became zero at around 520 nm that much smaller than NIR wavelengths. can therefore be measured...

Autoionisation of potassium ions, K+, and atoms, K, are studied by means ejected electron spectroscopy. Low-lying doubly excited states K+ K identified. The core 3s3p64s 1Se, 3s3p63d 1De 3s3p64p 1P0 autoionising They observed at 5.28, 6.59 8.01 eV above the K2+ 3s23p5 2P32/0 state, respectively. Configuration interaction calculations carried out on these states. It is suggested that core-excited state through configuration mixing with double

X-ray excited green colored optical luminescence with peak wavelength at 520 nm was observed from Mn doped spinel (MgAl2O4) crystal under Cu Kα irradiation. Peak intensity of increased linearly changed by tube current and voltage. larger than that Tl CsI which widely used as a scintillator. Bright is suggested to be useful for detection (especially CuKα detection) Si photo-devices (PD /or CCD) human eye.

Abstract Sm-doped TiO 2 thin films were synthesized by pulsed laser deposition. The luminescence and donor-generation properties of annealed at various temperatures investigated. results showed that Sm-related emissions occurred in the temperature range 500 °C–800 °C. donor densities this two orders magnitude higher than undoped film. effect annealing within window indicates a local fine structural transition ligands around Sm 3+ ions from T d symmetry to lower C 4v one; these are effective...

Photoluminescence (PL) spectra, intensities, and image brightness of 0.1–6.0 at% Cr-doped ruby were investigated across temperatures ranging from 24° to 600 °C. PL emissions at λ = 670, 694, 707, 715 nm observed in rubies doped with 0.1–1.0 Cr. In higher doping levels 1.5–6.0 Cr, an additional emission 770 was detected. intensities 715, decreased increasing °C, while the intensity 670 showed a similar temperature-dependent decrease. The variation temperature, particularly increase 200 is...

A fluorescence thermometer using the temperature dependence of phase shift response was developed a ruby phosphor sheet. The sheet compounded powder and silicone resin. lifetime from measured with measurement technique. decreased linearly 270to350K. is found to be powerful tool for measurement, can used noncontact measurement.

Thermal imaging technique is useful for detecting 2-dimensional spatial distribution and temporal variation of temperature. images foods during the cooking process and/or pulse heating are observed evaluating quality in volume fabrications. Inhomogeneous temperature a pancake can be baking process. Water concentration flour measured from evaluation thermal images.

Luminescence properties of Mn doped MgAl2O4 crystals connected with the Si PIN photodiode (PD) have been evaluated for X-ray detector applications. emit green colored luminescence peaking at around λ = 520 nm CuKα irradiation. The intensity output signal from PD increases linearly generated tube a current 2 mA to 40 mA. excited is strongest in specimen 3.0 mol. % Mn. Afterglow weak 2.0 considered be useful detector.