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Preparation of microspherical granules from aerosilogels

The way of spray drying in overheated water steam

Journal of Thermal Analysis and Calorimetry
Authors: Jadwiga Skubiszewska-Zięba and V. Sydorchuk

Abstract  

The influence of the conditions of aerosil dispersion spray drying process in the medium of overheated water steam on the formation of microspheric granules and their porous structure was studied. Water and ammonium solutions as aerosil particles dispersing agents and water steam and air as heat carriers were used. It was stated that the effects of spray drying depend on the kind of dispersing medium and on the conditions of atmosphere and temperature at which drying and forming of aerosilogel granules takes place.

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Abstract  

Radiochemical technique was used to investigate cryogenic chemical reaction. By introducing reactants of H and T into liquid 3H through 3He(n,p)T reaction, behaviors of H+T→HT and T+T→T2 were investigated under pressurized condition. Within saturated vapor pressure upto 0.61 Mpa, the isotope ratio of HT/T2 changed. It was suggested that the change of HT/T2 was attributed to bubble formation and chemical potential in liquid helium.

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Metastable effects on martensitic transformation in SMA

Part II. The grain growth effects in Cu-Al-Be alloy

Journal of Thermal Analysis and Calorimetry
Authors: A. Sepulveda, R. Muñoz, F. Lovey, C. Auguet, A. Isalgue, and V. Torra

Abstract  

The efficiency of shape memory alloy (SMA) as damper and/or standard actuator is truly enhanced when the material can be cycled without any relevant accumulation of the permanent deformation (i.e. under 0.5% for several hundreds of cycles). The particular properties of the CuAlBe alloy permit relevant grain growth with reasonable reduction of mechanical properties (from 300–350 to 250–300 MPa at fracture). Samples prepared with an appropriate heat thermal treatment (HTT) and relevant mean diameter of grain avoids accumulative deformation for series of cycles (near 500) up to 3.5% of deformation. The analysis of different wires of CuAlBe alloy shows, in the first part of HTT, a proportionality between the grain surface and the time at 1123 K. In the last part of the HTT the grain growth shows an increased complexity related with interactions between the grain boundaries and the external surface of the samples.

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Abstract  

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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Abstract  

Neutron Activation Analysis (NAA) was applied to the characterization of lithious ceramic materials to be used as tritiogenic breeders in future fusion reactors. After neutron irradiation, measurements by -spectrometry were performed on the activated impurities, particularly on the ones with large neutron cross section. Irradiated samples were then annealed at rising temperatures, to obtain a fractional release of the tritium [formed by (n,) reaction on lithium] as element (HT/T2) or tritiated water (HTO/T2O). Barium and antimony were determined by NAA, on request of Italian Courts, as evidence of gunshot residues (GSR), on hands and clothes of suspected people. The sample is left unchanged, even if slightly radioactive, allowing further examinations, in case of controversial results. In some actual cases, NAA was performed on sample already examined by scanning electron microscopy (SEM/EDX), allowing the determination of several more elements and a more definite identification of the ammunitions involved in the crime.

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Hegedűs G.: Arthur Conan Doyle. htt://www.literatura.hu/irok/real/doyle.htm. Moravcsik E.: Elmekór és Gyógytan. Universitas, Budapest, 1914. Moravcsik E

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Pokorný, J., Schmidt, Š. & Nguyen, H.T.T. (2004): Functionality changes of natural antioxidants during food processing and storage. Czech J. Food Sci. , 22 , 80–83. Nguyen H.T.T

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Viorel Chihaia, Karl Sohlberg, Margarita Gabrovska, Rumeana Edreva-Kardjieva, Dorel Crişan, Peter Tzvetkov, Maya Shopska, and Iskra Shtereva

, the products were filtered off, dried overnight at 60 °C and designated as x NiAl-HTT, for example 3.0NiAl-HTT. The tested catalysts were marked as x NiAl-t. To get reference counterparts for some characterizations of the investigated

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: moderation by a polymorphism in the 5-HTT gene. Science, 2003, 301 , 386–9. Moffitt T. E. Influence of life stress on depression: moderation by a polymorphism in the 5-HTT gene

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: Moderation by a polymorphism in the 5-HTT gene Science 301 386 389 . H. Cohen D

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