Pulse thermal analysis

Pulse thermal analysis (PulseTA ) [1] eliminates, or at least reduces, the difficulties mentioned above. PulseTA is based on the injection of a specific amount of the gases or liquids into the inert carrier gas stream and subsequent monitoring of changes in the mass, enthalpy and gas composition, resulting from the incremental reaction extent. Because a known amount of the selected gas, which can be used for calibration, is injected into the system, the method is also suitable for quantification of the evolved gas by mass spectrometry (MS) or Fourier transform infrared spectroscopy (FTTR). In contrast to conventional TA and all its modifications, the reaction is controlled not only by the temperature, but also by a distinct change in the composition of the reactive atmosphere. 

Pulse thermal analysis has also been applied in investigating the adsorption ... 

Pulse thermal analysis extends the versatility of conventional thermoanalytical methods by providing a means for studying differential reaction progresses. This advantage is combined with all the opportunities of thermogravimetry, differential thermal analysis or differential scanning calorimetry and evolved gas analysis. The primary benefits of the new method are ... 

Maciejewski et al. [74] convincingly demonstrated the complexity of the ostensibly simple decomposition of CoC204 2H2O, by applying a combination of experimental techniques including TG, DTA, DSC, X, TG-MS, and pulse thermal analysis. The process was demonstrated to involve numerotis reactions that occur in both the solid and gas phases. 

CHAPTER 4. PULSE THERMAL ANALYSIS (M. Maciejewski and A. Baiker)... 

Application of thermal analysis has also been extended by the development of pulse thermal analysis (PTA). This method is based on injection of a specific amount of the gaseous reactant(s) into an inert carrier gas stream at any temperature (non-isothermal) and/or time (isothermal mode) and monitoring of changes in mass, enthalpy and gas composition resulting from an incremental reaction extent [212]. The method is suitable for the quantification of the evolved gas by MS or FTIR due to... 

Recently it has been shown that the double-stranded RNA and its thermally denatured form behave in a similar manner to native and denaturated DNA [109]. Pulse-polarographic analysis in connection with a gel electrophoresis can be used for testing double-stranded RNA-samples prepared for biological experiments (interferon-inducing and antiviral activities). 

X-ray diffraction patterns were recorded on a Siemens D5000 diffractometer using CuKa radiation. Thermogravimetric and differential thermal analysis curves were recorded on a Setaram Setsys 12 thermal analysis station by heating in an argon atmosphere from 25 to 1200 -C at a rate of 5 min". Samples were used untreated. The Pt content was determined by the Service Central d Analyse, CNRS (Vernaison, France) and the microanalyses (C, H) were performed at Complutense University (Madrid, Spain). Na isotherms were determined on a Micromeritics ASAP 2000 analyzer. H MAS NMR, Si MAS NMR and C CP MAS NMR spectra were recorded at 400.13, 79.49 and 100.61 MHz, respectively, on a Broker ACP-400 spectrometer at room temperature. An overall 1000 free induction decays were accumulated. The excitation pulse and recycle time for H MAS NMR spectra were 5 ps and 3 s, respectively, those for Si MAS NMR spectra 6 ps and 60 s and those for C CP MAS NMR spectra 6 ps and 2 s. Chemical shifts were measured relative to a tetramethylsilane standard. Prior to measurement, if necessary, samples were dehydrated in a stove at 423 K for 24 h. 

These methods are dilatometry [14], infrared spectroscopy [15], viscoelastic measurements [16-20], thermal analysis [17,21-34], nuclear magnetic relaxation in both broad-line NMR and pulsed NMR [17,35], and dielectric [36], piezoelectric [37], and acoustic [38] measurements. 

E. Barsoukov, J.H. Jang, and H. Lee, Thermal impedance spectroscopy for Li-ion batteries using heat-pulse response analysis, Journal of power sources, vol. 109, no. 2, pp. 313-320, 2002. 

The SFC is a critical parameter for the fats and oils industry. The official American Oil Chemists Society (AOCS) wet method is dilatometery. Alternative wet methods are differential thermal analysis and differential scanning calorimetry (DSC). LR NMR was proved to be an alternative method for SFC determination in late 1950s. The early continuous wave LR NMR spectrometers rapidly found their way into the fats and oils industry, the method being accepted by the Instrumental Techniques Committee of the AOCS as early as in 1972. Presently the technical choice is radio frequency (RF) pulsed LR NMR. Pulse NMR spectrometers are more compact, very efficient, and relatively cheap. They have the advantage of exciting the protons in the whole sample at once. 

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