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Die trachtgeschichtliche Studie möchte ein – gegenüber dem bisher bekannten – vollständigeres Bild von einer spezifischen Variante der awarenzeitlichen Frauenkleidung bieten, die vor allem die Kleider schmückt oder zu ihnen gehört und durch Zierden aus bleibendem Material und kleinere Gegenstände erkennbar ist. Es handelt sich um eine Tracht, deren Wurzeln sich in der spätantiken, mediterranen und germanischen Welt finden lassen. Die betonten und leicht erkennbaren Stücke/Bestandteile dieser Tracht befinden sich an dem Teil der Kleidung unterhalb der Taille. Es handelt sich um den mit Beschlägen und Riemenzunge verzierten lang herabhängenden Gürtel, die an der linken Gürtelseite hängende Kapsel, Tasche oder Scheibe, Geräte (Messer, Schlüssel, Nadelbehälter aus Blech, Spinnwirtel), großgliedrige Bronzeketten bzw. große bunte Perlen oder Metallbeschläge als Schmuck von Textilbändern oder Lederriemen und schließlich die Metallschnallen und Riemenzungen der Lederriemen zur Befestigung des Lederschuhwerks oder der Strümpfe.

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Abstract  

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

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Abstract  

In this study, combustion curves of twenty-five Turkish lignites were obtained through use of a differential thermal analyser. 20 mg lignite samples were heated at a constant rate of 10 deg·min−1 in a 40 cc/min flow of air up to 1073 K and held for 10 minutes at this constant temperature. The combustion curves of the samples are compared and discussed.

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Abstract  

The injection calorimeters are used to evaluate thermodynamic properties of the mixtures and solutions. TheH i E partial molar excess enthalpies or theL υ, i relative apparent molar enthalpies against mole fraction are available from an appropriate signal processing of the calorimetric curves. An evolution of the thermal properties of the calorimetric vessel are associated with the injection process. Description of calorimetric equipments by means of a localized—constants model (RC analogy) allows us to systematize and to extent these systems into time dependent situations. Experimental measurements based on Joule effects and associated mathematical analysis permits to determine the absolute limits of the dynamic behaviour of these equipments from several standard and easily experimental parameters (sensitivity, noise level, τ1 the first time constant, sampling period). Models and experimental study provide an estimation of the corrections in order to compensate the evolution of the physical characteristics of the device.

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Calcium chromite, CaCr2O4, was prepared and its purity and stoichiometry were ascertained by chemical analysis and X-ray diffraction methods. The thermal diffusivity, specific heat capacity and thermal conductivity of calcium chromite were measured by Laser Flash method using an Ulvac-Sinku Riko TC-3000 series instrument in the temperature range of 298 to 1100 K. The heat capacity data were utilised to calculate the thermodynamic parametersenthalpy increments, entropy increments and free energy increments—in the above temperature range.

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Abstract  

A new sensitive isothermal titration microcalorimeter using polyvinylidene difluoride (PVDF) as detector has been developed. Heat pulses of less than 0.4 μJ can be detected and the baseline noise level (p-p) is 40 nW. The calorimeter is constructed with one reaction cell (0.7 ml) insulated by several radiation shields inside a vacuum chamber. The performance of the instrument was examined by measuring the heat of protonation of Tris with HCl. The enthalpy of reaction was found to be −49±1 kJ·mol−1, in good agreement with the reported value of −47.5 kJ·mol−1.

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The feasibility of the use of potassium nitrate and potassium perchlorate as temperature standards in Differential scanning calorimetry has been studied. The solid-state phase transition temperatures of KNO3 and KClO4 were determined by means of DSC. The metrological properties of these salts as calibration materials were examined. The reliability of KNO3 and KClO4 calibrations was investigated by twofold determination of the bismuth melting temperature after the apparatus had been calibrated with indium and lead, and with KNO3 and KClO4. Conclusions were drawn concerning the suitability of these salts for use as DSC temperature calibrants.

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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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Thermal analyses was performed on Egyptian date kernels to assess the value of the products as possible sources of valuable compounds. It also furnished technical data necessary for determination of the optimum degree of temperature for the design and operation of units for the pyrolytic processing of date kernels.

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Abstract  

The development of a temperature control system based on semiconductor thermobatteries has been used in a set of devices for studying the martensitic transformation. The devices range from a simple stage for an optical microscope to a more elaborated system as a differential scanning calorimeter [1]. Here the attention is placed in this last system. The general problems of the temperature scanning calorimetry are reviewed from the signal theory point of view and the solutions applied to our system discussed. Some measurements are shown as an example of its application.

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