Phosphor Thermometry by Using Rare Earth-Doped Yttrium Oxides

2011 ◽  
Author(s):  
Naohiro Ishiwada ◽  
Satoko Fujioka ◽  
Toshihisa Ueda ◽  
Takeshi Yokomori
Keyword(s):  
Intensity Ratio ◽  
Color Change ◽  
Thermal Quenching ◽  
Ratio Method ◽  
Temperature Dependent ◽  
Phosphor Material ◽  
Emission Color ◽  
Phosphor Thermometry ◽  
Increasing Temperature ◽  
Rare Earth Doped

The development of new temperature-dependent phosphor particles for high temperature thermometry is presented. To develop the phosphor material that can be applied to the intensity ratio method, the photoluminescence of Y2O3:Tb,Tm was investigated with elevating temperature. As a result, Y2O3:Tb,Tm phosphor shows that the peak intensity at 456 nm is still strong at more than 1100 K whereas the other peak intensities decrease due to the thermal quenching. Thus, the intensity ratio I543nm/I456nm has a high gradient and linearity over a wide temperature range, and it is confirmed that Y2O3:Tb,Tm provides a higher resolution in temperature measurement than Y2O3:Tb and Y2O3:Tm. Also, since this phosphor changes its emission color from green to blue with increasing temperature, it is possible to measure temperature not only by analyzing the intensity ratio but also by observing the color change in appearance. It can, therefore, be expected to use as a Visual Thermo-Sensor (VTS).

In-cylinder thermographic PIV combined with phosphor thermometry using ZnO:Zn

2021 ◽  
pp. 146808742110485
Author(s):  
Andreas Kopf ◽  
Valerio Frattina ◽  
Michele Bardi ◽  
Torsten Endres ◽  
Gilles Bruneaux ◽  
...  
Keyword(s):  
Fuel Injection ◽  
Thermal Quenching ◽  
Temperature Fields ◽  
Ratio Method ◽  
Calibration Data ◽  
Two Dimensional ◽  
Ic Engine ◽  
Thermographic Phosphor ◽  
Phosphor Thermometry ◽  
Coated Surfaces

Two-dimensional thermographic particle image velocimetry (T-PIV) is presented for the in situ measurement in optically accessible internal combustion (IC) engines. Temperature and velocity measurements are combined using thermographic phosphor particles as tracers for PIV. For three commercially available phosphors (BAM:Eu2+, ZnO, and ZnO:Zn), temperature sensitivity, luminescence intensity at high temperatures and laser-fluence dependence were evaluated for phosphor-coated surfaces in a high-temperature cell. ZnO:Zn was identified as the best-suited candidate for engine in-cylinder measurements and further analyzed in the aerosolized state at temperatures up to 775 K to generate calibration data required for signal quantification in engine experiments. T-PIV was successfully applied in the IC engine to simultaneously obtain instantaneous two-dimensional velocity and temperature fields using the intensity-ratio method. Despite a measurement uncertainty (±1σ basis) of only 3.7 K at 317 K (1.2%) to 24.4 K (4.2%) at 575 K, this technique suffers from low signal intensities due to thermal quenching at increasing temperatures, which leads to reduced accuracy as the piston approaches top dead center. Thermographic measurements were successful to visualize local temperature changes due to evaporative cooling after fuel injection. The measured mean gas temperatures agreed well with zero-dimensional simulations that use additional wall-temperature measurements from thermographic phosphor measurements based on the lifetime method as input for heat transfer calculations.

YAG : R3+ (R = Ce, Dy, Yb) nanophosphor-based luminescent fibre-optic sensors for temperature measurements in the range 20–500 °C

2022 ◽  
Vol 52 (1) ◽  
pp. 94-99
Author(s):  
S K Evstropiev ◽  
V V Demidov ◽  
D V Bulyga ◽  
R V Sadovnichii ◽  
G A Pchelkin ◽  
...  
Keyword(s):  
Thermal Quenching ◽  
Signal Amplitude ◽  
Temperature Sensors ◽  
Yttrium Aluminium Garnet ◽  
Optical Fibres ◽  
Fibre Optic ◽  
Excitation Light ◽  
Yttrium Aluminium ◽  
Increasing Temperature ◽  
Silica Capillary

Abstract We report the development of a group of luminescent fibre-optic temperature sensors that use Ce3+-, Dy3+-, and Yb3+-doped yttrium aluminium garnet (YAG) nanophosphors as thermosensitive materials. The nanophosphors have been prepared in the form of powders with a crystallite size from 19 to 27 nm by a polymer ? salt method and exhibit bright luminescence at 550 (YAG : Ce3+), 400, 480 (YAG : Dy3+), and 1030 nm (YAG : Yb3+). The sensor design includes a silica capillary, partially filled with a nanophosphor, and two large-aperture multimode optical fibres located in the capillary, which deliver excitation light and receive and transmit the photoluminescence signal. The photoluminescence signal amplitude of all the sensors decreases exponentially with increasing temperature, pointing to characteristic thermal quenching of photoluminescence and adequate operation of the devices up to 500 °C. The highest temperature sensitivity among the fibre-optic sensors is offered by the YAG : Ce3+ nanophosphor-based devices.

Photochromism and emission-color change in Ba3MgSi2O8-based phosphors

2016 ◽  
Vol 173 ◽  
pp. 237-242 ◽  
Author(s):  
Yoshinori Yonezaki ◽  
Shino Takei
Keyword(s):  
Color Change ◽  
Emission Color

scholarly journals Monitoring the temperature-dependent elastic and anelastic properties in isotropic polycrystalline ice using resonant ultrasound spectroscopy

2016 ◽  
Vol 10 (6) ◽  
pp. 2821-2829 ◽  
Author(s):  
Matthew J. Vaughan ◽  
Kasper van Wijk ◽  
David J. Prior ◽  
M. Hamish Bowman
Keyword(s):  
Sea Ice ◽  
Ice Cores ◽  
Compressional Wave ◽  
Temperature Dependent ◽  
Resonant Ultrasound Spectroscopy ◽  
Polycrystalline Ice ◽  
Passive Seismic ◽  
Resonant Ultrasound ◽  
Increasing Temperature ◽  
Quality Factor Q

Abstract. The elastic and anelastic properties of ice are of interest in the study of the dynamics of sea ice, glaciers, and ice sheets. Resonant ultrasound spectroscopy allows quantitative estimates of these properties and aids calibration of active and passive seismic data gathered in the field. The elastic properties and anelastic quality factor Q in laboratory-manufactured polycrystalline isotropic ice cores decrease (reversibly) with increasing temperature, but compressional-wave speed and attenuation prove most sensitive to temperature, indicative of pre-melting of the ice. This method of resonant ultrasound spectroscopy can be deployed in the field, for those situations where shipping samples is difficult (e.g. remote locations), or where the properties of ice change rapidly after extraction (e.g. in the case of sea ice).

Rare Earth Doped Zinc Oxide Nanowires

2008 ◽  
Vol 8 (1) ◽  
pp. 244-251 ◽  
Author(s):  
S. Geburt ◽  
D. Stichtenoth ◽  
S. Müller ◽  
W. Dewald ◽  
C. Ronning ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Rare Earth ◽  
Thermal Quenching ◽  
Wide Band ◽  
Wide Band Gap ◽  
Oxide Nanowires ◽  
Defect Sites ◽  
Optical Activation ◽  
Re Elements ◽  
Rare Earth Doped

Zinc oxide (ZnO) nanowires were grown via thermal transport and subsequently doped with different concentrations of Tm, Yb, and Eu using ion implantation and post annealing. High ion fluences lead to morphology changes due to sputtering; however, freestanding nanowires become less damaged compared to those attached to substrates. No other phases like rare earth (RE) oxides were detected, no amorphization occurs in any sample, and homogeneous doping with the desired concentrations was achieved. Photoluminescence measurements demonstrate the optical activation of trivalent RE-elements and the emission of the characteristic intra-4f-luminescence of the respective RE atoms, which could be assigned according to the Dieke-diagram. An increasing RE concentration results into decreasing luminescence intensity caused by energy transfer mechanisms to non-radiative remaining implantation defect sites. Furthermore, low thermal quenching was observed due to the considerable wide band gap of ZnO.

Temperature Dependent Raman Scattering in CsTiOAsO4 Single Crystal

1995 ◽  
Vol 398 ◽  
Author(s):  
A.R. Guo ◽  
C.-S. Tu ◽  
Ruiwu Tao ◽  
R.S. Katiyar ◽  
Ruyan Guo ◽  
...  
Keyword(s):  
Soft Mode ◽  
Low Frequency ◽  
High Mobility ◽  
Vibrational Modes ◽  
Frequency Range ◽  
Temperature Dependent ◽  
Higher Symmetry ◽  
Phonon Spectra ◽  
Symmetry Structure ◽  
Increasing Temperature

ABSTRACTThe longitudinal (LO) and transverse (TO) A1 vibrational modes have been measured between 30-1200 cm−1 as a function of temperature (30–1240 K) for CsTiOAsO4 (CTA). The frequencies for all corresponding Raman components shifted to lower frequencies on increasing the temperature, however, there is no typical soft-mode like behavior observed in the measured frequency range. The relative intensities of the low frequency bands increase dramatically with increasing temperature due to high mobility of Cs+ ion. A higher symmetry structure taking place above 940K has been confirmed by changes in the phonon spectra.

Morphological basis for the complex melting behaviour of isotactic polystyrene

e-Polymers ◽  
2002 ◽  
Vol 2 (1) ◽  
Author(s):  
Mahmoud Al-Hussein ◽  
Gert Strobl
Keyword(s):  
Morphological Changes ◽  
Melting Behaviour ◽  
Temperature Dependent ◽  
Molten Material ◽  
Scanning Calorimetry ◽  
Isotactic Polystyrene ◽  
X Ray ◽  
Long Period ◽  
X Ray Scattering ◽  
Increasing Temperature

AbstractTemperature-dependent small-angle X-ray scattering spectroscopy of isothermally cold crystallized isotactic polystyrene revealed considerable morphological reorganization during subsequent heating to the melt. Both the crystalline thickness and the long period increased continuously with increasing temperature before the samples finally melted. The temperature dependence of these changes correlated very well with the melting behaviour observed with differential scanning calorimetry. As the temperature increased during a heating scan, the initial lamellae that formed during isothermal crystallization showed only little reorganization until they started to melt. Then, the molten material recrystallized continuously into increasingly thicker lamellae at increasing temperature until they finally melted. As the crystallization temperature approached the final melting temperature of the recrystallized lamellae, the initial lamellae melted without further recrystallization and no morphological changes were seen in this case.

Temperature-dependent survival and reproduction within populations of the ectoparasitic digenean Transversotrema patialense on the fish host

Parasitology ◽  
1980 ◽  
Vol 81 (1) ◽  
pp. 91-102 ◽  
Author(s):  
C. A. Mills
Keyword(s):  
Life Span ◽  
Egg Production ◽  
Fish Host ◽  
Adult Parasite ◽  
Optimum Temperature ◽  
Brachydanio Rerio ◽  
Temperature Dependent ◽  
Parasite Survival ◽  
Survival And Reproduction ◽  
Increasing Temperature

SUMMARYThe reproduction and survival of the ectoparasitic digenean Transversotrema patialense on the fish host Brachydanio rerio are shown to be temperature-dependent. Survival is reduced by any deviation from an optimum temperature of approximately 23°C. With increasing temperature the rate of egg production per surviving fluke rises progressively faster to a higher peak up to 29°C but falls to zero by 35°C. The span of egg production varies closely with the life-span of the parasite at each temperature. The optimum temperature for the total number of eggs produced by each cohort of parasites is also 23°C. This number is a function of both adult parasite survival and the rate of egg output.

Temperature Dependent Behavior of the Canine Medial Collateral Ligament

1987 ◽  
Vol 109 (1) ◽  
pp. 68-71 ◽  
Author(s):  
Savio L.-Y. Woo ◽  
Thay Q. Lee ◽  
Mark A. Gomez ◽  
Shigeru Sato ◽  
Frederic P. Field
Keyword(s):  
Medial Collateral Ligament ◽  
Viscoelastic Properties ◽  
Cyclic Load ◽  
Tensile Load ◽  
Temperature Dependent ◽  
Collateral Ligament ◽  
Dependent Behavior ◽  
Proportional Relationship ◽  
C 32 ◽  
Increasing Temperature

The temperature dependent tensile behavior of ligament was investigated from 2°C to 37°C. Nondestructive cyclic tests were performed on ten canine femur-medial collateral ligament-tibia (FMT) complexes at sequential temperatures of 22°C, 22°C, 27°C, 32°C, 37°C, and again at 22°C. The samples were rested at zero load between tests for sufficient time periods to allow for full recovery from the ligament’s time and history dependent viscoelastic properties. Ten additional FMT complexes were sequentially tested in a similar fashion, but at temperatures of 22°C, 22°C, 2°C, 6°C, 14°C, and 22°C. All canine FMT complexes showed temperature dependent viscoelastic properties: the measured area of hysteresis decreased with increasing temperature; the cyclic load relaxation behavior plateaued to a higher value at lower temperatures; and the tensile load at a predetermined ligament substance strain level had an inversely proportional relationship with respect to temperature.

scholarly journals The influence of temperature on methane adsorption in coal: A review and statistical analysis

2019 ◽  
Vol 37 (9-10) ◽  
pp. 745-763 ◽  
Author(s):  
Zhijun Wang ◽  
Xiaojuan Wang ◽  
Weiqin Zuo ◽  
Xiaotong Ma ◽  
Ning Li
Keyword(s):  
Coalbed Methane ◽  
Methane Adsorption ◽  
Gas Content ◽  
Future Research ◽  
Temperature Dependent ◽  
Current State ◽  
Influence Of Temperature On ◽  
State Of Research ◽  
Increasing Temperature ◽  
The Relationship

The capacity of coal to adsorb methane is greatly affected by temperature and, in recent years, temperature-dependent adsorption has been studied by many researchers. Even so, comprehensive conclusions have not been reached and conflicting experimental results are common. This paper reviews the current state of research regarding the temperature-dependent adsorption of methane in coal and catalogs the conclusions from experiments conducted on that subject by 28 researchers, as published between 1995 and 2017. Probability theory and statistics are used to show that the conclusion generally accepted by most researchers is that the amount of methane adsorbed by coal decreases with increasing temperature. It is highly likely that the Langmuir volume decreases as the temperature rises, and it is also probable that the Langmuir pressure increases at higher temperatures. Equations are presented that express the relationships between methane adsorption, Langmuir volume, Langmuir pressure, and temperature. Future research should be directed toward determining the relationship between Langmuir pressure and temperature. The results of the study presented herein provide a theoretical basis for predicting the gas content in coal seams and improving the efficiency of coalbed methane development.

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