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Peak shift is a universal result of most discrimination learning: if an organism is taught to respond to one stimulus and not to respond to another stimulus lying along the same perceptual continuum, it shows maximal responsiveness not to the target stimulus but to a stimulus displaced along the continuum in a direction away from the unreinforced stimulus. It also responds more vigorously to the displaced stimulus than it would have to the target stimulus had discrimination training not occurred. This is the phenomenon of behavioral contrast. On the level of preference, peak shift means that if we prefer something, we shall like something a bit more extreme even more. Peak shift and behavioral contrast are probably the most important causes of sound change in language, but this has never been pointed out. The relevance of peak shift and behavioral contrast to phonological change is explained. Their most general consequence is that the phonetic realization of phonemes is usually in a continual state of evolution; because learners systematically overshoot the phonetic realization they are being taught. How peak shift could have caused the Great English Vowel Shift and the changes subsumed by Grimm's Law is explained. Both of these effects involved chains of phonemes that differed in frequency of occurrence along a gradient. In such cases, peak shift and behavioral contrast very quickly bring about massive changes in pronunciation that can affect virtually every word in a language.

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Pollack Periodica
Authors: Istvan Ervin Haber, Gergely Bencsik, Basma Naili, and Istvan Szabo

described by Rezaie and Rosen [ 22 ]. This all means above that a thermal storage is absolutely suitable for peak shifting, resulting cost reduction and increasing efficiency of Photo Voltaic (PV) systems [ 23 ]. In special cases the legal regulations of a

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Abstract  

The far infrared absorption spectrum of the lithium perchlorate/benzo-15-crown-5 complex separated from various solvents has been investigated in the 250~590 cm-1 region. It has been found that the change in the medium used for the preparation of the complex probably leads to the change in the far infrared shift. A linear function of far infrared absorption band versus lithium isotope abundance in the complex was discovered. The far infrared absorption band of the complex containing 100% 6Li could be determined by extrapolation. A concept of relative reduced partition function ratio was proposed for the first time in order to calculate approximately the isotope effect of lithium by use of the data of the far infrared spectra.

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transition of EW follows the Arrhenius behavior and indicates the required activation energy for the transitions in the form of the slope of the line as plotted in Fig. 4 . The transition peak shifts linearly with the change in heating rate and hence brings

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Abstract  

The surface reactions of uranium metal with carbon monoxide at 25 and 200 °C have been studied by X-ray photoelectron spectroscopy (XPS); respectively. Adsorption of carbon monoxide on the surface layer of uranium metal leads to partial reduction of surface oxide and results in U4f photoelectron peak shifting to the lower binding energy. The content of oxygen in the surface oxide is decreased and O1s/O4f ratio decreases with increasing the exposure of carbon monoxide. The investigation indicates the surface layer of uranium metal has resistance to further oxidation in the atmosphere of carbon monoxide.

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Crystallization kinetics of Cu3Ti2 forming from Cu60Ti40 glass

Continuous heating experiments in XRD and DSC

Journal of Thermal Analysis and Calorimetry
Authors: E. Baburaj, G. Prasad, S. Banerjee, T. Raghu, and M. Patni

Abstract  

Amorphous to crystalline transformation in Cu60Ti40 alloy has been studied under conditions of constant heating rate experiments, using XRD and DSC. In the high temperature XRD experiment, the transformation has been monitored continuously as the integrated X-ray intensity corresponding to a chosen reflection from one of the two crystalline products forming at close by temperatures. Differentiation of the curve thus obtained gives the transformation rate curve which passes through a maximum. From the peak shift with heating rate, the activation energy for the formation of Cu3Ti2 crystalline phase has been obtained. The results have been compared with those obtained by DSC.

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Abstract  

Emission peak position on the apparent energy scale is a function of the number of photons created in the radioactive decay process. The sample, which is the detector in liquid scintillation (LS) spectroscopy, may contain quenching substances. These inhibit creation of photons and, consequently, radionuclide emission peak shifts towards lower channels. Identification of the radionuclide by its peak position is therefore not straightforward under variable quench in LS spectroscopy. The end point of the Compton spectrum (or external standard quench parameter SQP(E)) gives a direct measure of the sample quench. It is normally used in LS spectroscopy for the measurement of counting efficiency. Because SQP(E) does not depend on the sample emission energy, it can be used in verification of the peak energy together with the peak position. Two known energy calibration lines are required as a function of quench to verify the peak energy.

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Abstract  

Thermal analysis is increasingly being used to obtain kinetic data relating to sample decomposition. In this research differential scanning calorimeter (DSC) was used to determine the combustion kinetics of three (an, Himmetoglu and Mengen) oil shale samples by ASTM and Roger & Morris methods. On DSC curves two reaction regions were observed on oil shale sample studied except an oil shale. In DSC experiments higher heating rates resulted in higher reaction temperatures and higher heat of reactions. Distinguishing peaks shifted to higher temperatures with an increase in heating rate. Three different kinetic models (ASTM I-II and Rogers & Morris) were used to determine the kinetic parameters of the oil shale samples studied. Activation energies were in the range of 131.8-185.3 kJ mol-1 for ASTM methods and 18.5-48.8 kJ mol-1 for Rogers & Morris method.

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Abstract  

Nitrocellulose porosity was investigated by thermoporometry, based on melting point depression of liquid in limited space. Strange behaviour of water-saturated nitrocellulose was observed, which consisted of melting peak shifting of some of liquid. Thermal resistance, connected with limited contact area of nitrocellulose walls and water, is supposed as the source of phenomenon. Water is unable to completely penetrate into pores as nitrocellulose is a hydrophobic material, though prolonged stirring or boiling of mixture improves saturation. Thus total pore volume cannot be estimated correctly. In spite of this pore radius was calculated from obtained DSC curves. The results show good consistency for the same nitrocellulose materials, which proves that thermoporometry is a useful method of nitrocellulose characterisation.

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Abstract  

The crystallization kinetics of amorphous Cu50Ti50 has been studied using differential scanning calorimetry (DSC) under non-isothermal conditions. The curves at different linear heating rates (2, 4, 8 and 16 K min-1) show sharp crystallization peaks. The crystallization peak shifts to higher temperatures with increasing heating rate. The Kissinger's method of analysis of the shift in the transformation peak is applied to evaluate the activation energy (E c). The KJMA formalism, which is basically developed for isothermal experiments, is also used to obtain E c and the Avrami parameter (n). The DSC data have been analysed in terms of kinetic parameters, viz. activation energy (E c), Avrami exponent (n) and frequency factor K 0 using three different theoretical models. It is observed that the activation energy values derived from KJMA approach and modified Kissinger equation agree fairly well with each other. The activation energy values obtained from normal Kissinger method, and Gao and Wang expression underestimate the activation energy.

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