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Abstract  

A new approach is proposed for the measurement of the time-dependent processes in gamma-ray spectrometry. During data acquisition, the energy and the detection time of each event are recorded and the data are later analyzed off-line. This separation of acquisition and data handling extends the possibilities of the analysis. A series of demonstration experiments was performed to show the feasibility of the method, where the half-lives of radioactive isotopes were determined.

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]. However, no detailed information are available in the literature on the effect of annealing on charge storage and transport in ethyl cellulose (EC). In view of the above, the effect of annealing time on TSDC spectra of negatively charged EC has been

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.), Direct Analysis in Real Time Mass Spectrometry: Principles and Practices of DART-MS , John Wiley & Sons , New York, NY , 2018 . [4] G.E. Morlock

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References 1 ASTM D3895-95, “ Oxidative Induction Time of Polyolefins by DSC ”, American Society for Testing and Materials . 2 ASTM E0487-79, “ Constant Temperature

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dipole orientation Δ G* , enthalpy Δ H* , entropy of activation Δ S* , and the other temperature-dependent parameters, such as relaxation time τ, the distribution parameter α, and the dielectric constant at an infinitely high frequency. Liquid

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heat flux) enables us to make a relative comparison of materials or products from the point of fire dynamics. Induction period of ignition or flash ignition is defined as the time interval between the thermal loading of the sample at a constant

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Abstract  

A new method of the correction of counting losses caused by a non-extended dead time of pulse detection systems is presented. The approach is based on the distribution of time intervals between pulses at the output of the system.

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The heat capacityC p of a sample can be considered as a frequency dependent quantity; its behaviour can reflect the dynamics of enthalpy fluctuations. In order to take into account the dynamic nature of the measured quantity, calorimetry can mimic experimental methods as those of dielectrometry, performing experiments in time domain or in frequency domain.

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excellent agreement with the literature value of 17.22 kJ mol −1 [ 29 ]. Enthalpy calculations The overall enthalpy change, Δ H exp , was obtained by integration of the DSC curve as a function of time. The measured

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Abstract  

The Naval Research Laboratory’s Trace Element AMS system’s use of a Pretzel magnet as a recombinator and mass filter offers a unique opportunity to study a new type of time-of-flight (TOF) spectrometry. Mass filtering prior to TOF analysis removes extraneous species, shortening the analysis time for a single beam pulse, thereby improving the duty cycle. Time dilation results from a longer flight path for a heavier mass in the Pretzel magnet. Computer TOF simulations of these factors and the resulting impact on mass resolution for high mass atomic and molecular species are discussed. Initial measurements of carbon and silicon to confirm the validity of the model are presented.

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