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Abstract  

Scanning thermal microscopy (SThM) can measure thermal image with a nano-scale spatial resolution. However, there remains an issue in quantitative temperature measurement. We proposed an active temperature measurement method that provides a real temperature image by compensating a variation in contact thermal conductance. Performance of the active method was examined by a multi-function cantilever made with micro-fabrication process. Response test of the cantilever showed about 50 Hz cut off frequency for both passive and active method. Temperature measurement test indicated that sensitivity of heat flow detection was not enough to measure real temperature regardless of the thermal contact conductance. Imaging test demonstrated that the active method takes temperature image closer to real temperature distribution than the passive method.

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Temperature measurement and control

Critical parameters in thermal analysis techniques

Journal of Thermal Analysis and Calorimetry
Authors: R. Tye, R. Gardner, and A. Maesono

Abstract  

Several factors in temperature measurement that can affect the precision of melting points and phase-change phenomena are discussed. In many cases, critical errors may arise in the measurement and control of temperatures due to incorrect placement and/or interpretation of the output of temperature sensors in the various system types that are in current use. Advantages can be obtained by using one temperature sensor only for temperature measurement and temperature control in a low mass infrared gold image fumace for the analytical studies in both the constant rate and stepwise isothermal thermoanalytical heating and cooling modes. Illustrations of the use of this instrumentation for measurements in both modes are given.

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Main aim of this paper is to illustrate the experimental partial results of a study on various exterior wall fragments. The study was performed for selected wall fragments and time periods, with attention focused also on wall orientation (East and South) with identical layering and also on dynamic thermal parameters connected to the thermal comfort during summer and winter. Evaluation is done for real measured climate conditions in the area of experimental laboratory (exterior – University of Zilina) and interior conditions set according to the Slovak standard. For needs of the long-term experiment (since March 2017), temperature and relative humidity between layers are monitored. This paper deals specifically with the temperature measurement of selected days. For future publications also coupled heat-air-moisture transport analysis is intended. In this part of analysis, some extreme boundary conditions were selected and reviewed from the point of view of measured temperature inside the wall. Temperature peaks are characterized with respect to exposure to real atmospheric conditions.

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Abstract  

A complex of devices is described which consists of two thermal analysers (their working temperature ranges are 300–2500 K and 1000–3000 K) and a scanning calorimeter (its working temperature ranges from 300 to 2000 K) which are controlled by an automatic system based on IBM PC AT with the ADDA-14 card.

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Abstract  

Cryogenic techniques are currently used in scanning tunnelling microscopy (STM) and single molecule spectroscopy. Recently such cryogenic devices have also been adapted to time resolved laser-induced fluorescence spectroscopy (TRLFS) systems applied to uranium(VI). In our study, we interpret TRLFS results obtained for the uranyl(VI) glucose system at room temperature (RT) and under cryogenic conditions of 153 K (cryo-TRLFS). A uranyl(VI) glucose complex was only identified by cryo-TRLFS measurements at pH 5 and not by RT measurements. The uranyl(VI) glucose complex was characterized by five emission bands at 499.0, 512.1, 525.2, 541.7, and 559.3 nm and a fluorescence lifetime of 20.9 ± 2.9 μs. The uranyl(VI) glucose complex formation constant was calculated for the first time to be logßI=0.1 M = 15.25 ± 0.96. Cryo-TRLFS investigation opens up new possibilities for the determination of complex formation constants since interfering quenching effects often encounter at RT are suppressed by measurements at cryogenic conditions.

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Abstract  

In this paper problems associated with a conventional heat-flux DSC are discussed. A single pan calorimeter has been designed and built which eliminates many of the errors that occur in a conventional DSC. It was found that: enthalpy changes and heat capacity were repeatable to better than1%; the apparent latent heat and heat capacity did not depend on specimen size or significantly on rate of heating as often occurs in a two-pan heat-flux DSC; during the melting of pure Al, more than 80% of the latent heat was evolved over a temperature of 0.04 K; in alloys, separate heat capacity peaks for different reaction less than 1 K apart were resolved.

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Journal of Thermal Analysis and Calorimetry
Authors: I. Shishkovsky, V. Scherbakov, Y. Morozov, M. Kuznetsov, and I. Parkin

Abstract  

This work reports the temperature behavior associated with formation of new metal-polymer, intermetallic, and ceramic materials by Selective Laser Sintering. Here, experimental data produced from temperature measurements for inert as well as reaction powder compositions and the combustion wave front is reported. Analysis using an analog-digital-analog computer converter allowed some control of laser movement and hence some control of the exothermal reaction — in so doing it provided near optimum conditions for forming layered 3D articles.

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Journal of Thermal Analysis and Calorimetry
Authors: Grażyna Janowska, Agnieszka Kucharska-Jastrząbek, Przemysław Rybiński, Dorota Wesołek, and Iwona Wójcik

Abstract

This paper presents the results of testing the flammability and fire hazard of butadiene (BR), butadiene-acrylonitrile (NBR) and butadiene- styrene (SBR) rubbers with the use of oxygen index test, ignition temperature measurement, cone calorimetry and inverse liquid chromatography. Toxicometric indices, RTFH CO/CO2, WLC50SM and the concentration of polycyclic aromatic hydrocarbons (PAH) have been determined. The results obtained have been interpreted from the point of view of the chemical constitution of the polymers tested.

Open access

Abstract  

Perovskite type oxides of BaxCa1−xFe0.8Co0.2O3−δ withx=0.95, 0.8, 0.6 and 0.4 have been studied by57Fe transmission Mössbauer spectroscopy. The microenvironment of Fe was found to be sensitively dependent on the Ba to Ca ratio and, more importantly, on the oxygen content. At high Ba concentration, magnetic relaxation is indicated by the Mössbauer spectra. Identification of the various sextets and doublets in the Mössbauer spectra is attempted by the help of thermal treatments of the samples in air and methane as well as by quenching experiments and low temperature measurements.

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