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laws, other parameters that affect the burning rate are additives, acoustic and specific surface conditions. Seeing the importance of catalytic and pressure effect on the combustion process, the burning rate ( r ) of AN–HTPB-based solid propellants has

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The double perovskites, AFe0.5Mo0.5O3with A=(Ba,Sr) or (Sr,Ca), were prepared by a sol-gel method, and the substitution effect at site A was studied by Mössbauer spectrometry. In the Mössbauer spectra of the double perovskite (Ba, Sr)Fe0.5Mo0.5O3, the isomer shifts decreased fromδ=0.72 mm/s to δ=0.4 mm/s and the internal magnetic fields increased with the increase of the Sr content. The Ba-rich samples were shown to contain superparamagnetic components under the same preparation conditions. Better crystallinity and larger hyperfine fields were obtained when 5% of the Sr-content of SrFe0.5Mo0.5O3was substituted by Ca as compared with substitution by Ba. Phonon density of states (DOS) of SrFe0.5Mo0.5O3substituted with Ca or Ba were obtained by nuclear inelastic scattering. The peaks of phonon DOS were shifted, depending on chemical compression/expansion of the lattice. The chemical pressure effect could be observed in the Mössbauer spectra and the phonon DOS spectra.

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Summary The phase transformations in the three Ni-base alloys at the temperature range up to 1500°C and at the pressure of 170 MPa were studied. Solidus, ?’-phase dissolution/precipitation, carbides dissolution/precipitation and liquidus temperatures are established. Multiple exceeding of the Ni-base alloys characteristic temperatures pressure coefficients over metal components ones (up to 10 times) is observed both at the heating and cooling scans during the experiments on the differential barothermal analysis. On the DBA curves had been obtained at 170 MPa, there are from two to three peaks, which connected with the carbides dissolution/precipitation, while on the each conventional DTA curve there was merely one ‘carbide’ thermal effect. The liquidus temperature pressure coefficients correlate with the Ni melting point pressure coefficient.

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The behavior of recombinations of H+H→H2, H+T→HT and T+T→T2 in liquid helium at cryogenic temperature of 1.6 K was investigated under pressurized condition using radiochemical methods. It was found that the isotope ratios of H2, HT and T2 were changed with the pressure. The changes will contribute to the bubble formation, chemical potential and the effective masses of H and T. This work is a preliminary information to carry out chemical reactions in liquid helium.

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Behavior of the hydrogen isotope in recombination reactions, H+H→H2 H+T→HT and T+T→T2 under pressurized conditions at 1.6 K were investigated using liquid helium as cryogenic reaction media by radiochemical methods. Pressure effects were observed in changes of isotope ratio HT/T2. It became clearer that the balance of changes in bubble energy effective mass associated with energy and chemical potential contributed to the recombination reactions through bubble states. It was suggested that bubble radius was decreased significantly at higher pressure.

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The influence of pressure on the polyphenacylmethacrylate [poly(PAMA)] was investigated using thermal and scanning electron microscopical (SEM) methods. It is observed that the application of pressure reduces 10% of the initial glass transition temperature. A part from each of the sample was taken for thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). The activation energies were calculated by Ozawa method and significant changing was observed due to this calculation justified the effect of applying pressure.

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Distribution coefficients of fission products on a cation exchanger in 1M nitirc acid were measured as a function of the pressure by means of the column method. The distribution coefficients were found to decrease with the pressure, and this became more pronounced with increasing charge of the ions. The distribution coefficients of yttrium and RuNO3+ decreased with the pressure to a relatively greter extent than lighter lanthanides, and RuNO3+ appeared at a separate peak from europium in the elution chromatogram as the pressure was increased up to 900 kg/cm2.

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The effects of nitrogen (N2) pressure on amphiphilic di-block copolymer, PEO114-b-PMA(Az)40, were investigated by scanning transitiometry. The isotropic transition temperature increased with the increase of pressure above 20 MPa. The hydrostatic pressure effects evaluated with the Clapeyron equation were smaller than the value obtained by mercury as a pressurizing medium because the amount of absorbed gas decreases the volume change at the isotropic transition.

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The effects of high pressure carbon dioxide (CO2) on the isotropic transition of three different amphiphilic di-block copolymers, PEOm-b-PMA(Az)n, namely PEO114-b-PMA(Az)40, PEO272-b-PMA(Az)46 and PEO454-b-PMA(Az)47, and on PMA(Az)30 homopolymer have been investigated by scanning transitiometry. Under CO2 pressure, the isotropic transition temperature decreased with the increase of pressure up to around 30 MPa due to CO2 sorption and increased above 40 MPa. Transition entropy of the isotropic transition indicated that the depression of the isotropic transition temperature was caused by the adsorption of CO2 into the azobenzene moieties and that the increase above 40 MPa was caused by the desorption of CO2 into the azobenzene moieties. Comparison between PEOm-b-PMA(Az)n copolymers and PMA(Az) homopolymer clarified PEO domain acted CO2 pathway to approach the equilibrium state rapidly.

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This research is focused on the effects of pressure (100–300 Pa) and matrix and on light crude oil combustion in sandstone matrix using pressurized differential scanning calorimetry (PDSC). Light crude oils and sandstone mixtures were prepared to give a composition of 15 mass% crude oil in sandstone matrix. A total of forty-eight PDSC experiments were performed. Roger and Morris kinetic model was used to analyse the data obtained from PDSC experiments and the results are discussed.

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