The Experts below are selected from a list of 291 Experts worldwide ranked by ideXlab platform
Akira Sawaoka - One of the best experts on this subject based on the ideXlab platform.
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Amino acid synthesis from an Amorphous substance composed of carbon, nitrogen, and oxygen
Applied Physics Letters, 1998Co-Authors: Shin Miyakawa, Akira Sawaoka, Hideki Tamura, Kensei KobayashiAbstract:Hydrogen cyanide, formaldehyde, and ammonia are considered important intermediates in amino acid synthesis by electric discharge. In this study, however, amino acid precursors were synthesized from a CO–N2 mixture free of hydrogen atoms. An Amorphous Film composed of carbon, nitrogen, and oxygen was given from a highly activated plasma. When exposed to atmospheric moisture, this Film incorporated hydrogen atoms to yield amino acid. This is a mechanism for amino acid synthesis without involving hydrogen cyanide, formaldehyde, and ammonia.
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Epitaxial growth of strain‐free Ge Films on Si substrates by solid phase epitaxy at ultrahigh pressure
Applied Physics Letters, 1992Co-Authors: Hiroshi Ishiwara, Takayoshi Sato, Akira SawaokaAbstract:A novel method to solve the thermal mismatch problem in heteroepitaxial growth has been presented, in which an Amorphous Film deposited on a single‐crystal substrate is grown by solid phase epitaxy at ultrahigh pressure. It has been theoretically predicted in such systems as Ge/Si and GaAs/Si that the difference of the thermal expansion coefficient can be compensated by that of elastic strain generated by hydrostatic pressure. Experimentally, it has been found that the residual strain in Ge Films on Si substrates is linearly decreased with increase of the pressure during annealing, while the defect density in the Film is kept constant. It has been presumed from these results that a strain‐free Ge Film can be grown on a Si substrate by solid phase epitaxy at 2.5 GPa.
Joachim Yahalom - One of the best experts on this subject based on the ideXlab platform.
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Constant Voltage Anodizing of Mg‐Al Alloys in KOH ‐ Al ( OH ) 3 Solutions
Journal of The Electrochemical Society, 1998Co-Authors: Oscar Khaselev, Joachim YahalomAbstract:Constant voltage anodizing of binary Mg-Al alloys containing 2, 5, 8, and 12% of aluminum was studied. Anodizing was conducted in a bath containing 3 M KOH + 0.6 M KF + 0.21 M Na 3 PO 4 with additions of 0.013, 0.064, 0.13, and 0.4 M of Al(OH) 3 . A thin Amorphous Film was formed during the first stage of anodizing. Prolonged anodizing caused local breakdown and crystallization of the initially formed anodic Films. The chemical composition of the newly formed crystalline Film was determined. The elements in the Film were mainly magnesium, aluminum, and oxygen. Aluminum penetrated into the Film both from the electrolyte and from the Mg-Al alloy substrate. The phase composition of the anodic Films was found to be a mixture of MgO and MgAl 2 O 4 .
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constant voltage anodizing of mg al alloys in koh al oh 3 solutions
Journal of The Electrochemical Society, 1998Co-Authors: Oscar Khaselev, Joachim YahalomAbstract:Constant voltage anodizing of binary Mg-Al alloys containing 2, 5, 8, and 12% of aluminum was studied. Anodizing was conducted in a bath containing 3 M KOH + 0.6 M KF + 0.21 M Na 3 PO 4 with additions of 0.013, 0.064, 0.13, and 0.4 M of Al(OH) 3 . A thin Amorphous Film was formed during the first stage of anodizing. Prolonged anodizing caused local breakdown and crystallization of the initially formed anodic Films. The chemical composition of the newly formed crystalline Film was determined. The elements in the Film were mainly magnesium, aluminum, and oxygen. Aluminum penetrated into the Film both from the electrolyte and from the Mg-Al alloy substrate. The phase composition of the anodic Films was found to be a mixture of MgO and MgAl 2 O 4 .
Yasuhiko Shirota - One of the best experts on this subject based on the ideXlab platform.
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surface relief grating formation using a novel azobenzene based photochromic Amorphous molecular material tris 4 phenylazo phenyl amine
Molecular Crystals and Liquid Crystals, 2005Co-Authors: Toru Takahashi, Takahiro Tanino, Hiroyuki Ando, Hideyuki Nakano, Yasuhiko ShirotaAbstract:ABSTRACT A novel azobenzene-based photochromic Amorphous molecular material, tris[4-(phenylazo)phenyl]amine (TPAPA), was designed and synthesized. TPAPA was found to readily form an Amorphous glass with a glass-transition temperature of 67°C and to exhibit photochromism as Amorphous Film. Irradiation of Amorphous Film of TPAPA with two coherent Ar+ laser beams led to the formation of surface relief grating with a diffraction efficiency of 2 ≈ 3% and a modulation depth of ca. 100 nm.
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formation of a surface relief grating using a novel azobenzene based photochromic Amorphous molecular material
Advanced Materials, 2002Co-Authors: Hideyuki Nakano, Toru Takahashi, Toshiaki Kadota, Yasuhiko ShirotaAbstract:A new photochromic Amorphous molecular material based on an azobenzene, BFIAB, has been designed and synthesized. BFlAB readily forms an Amorphous glass with a glass-transition temperature of 97 °C and exhibits photochromism in the Amorphous solid Film as well as in solution. The BFlAB Amorphous Film forms a surface relief grating (see Figure) with a high diffraction efficiency and a large modulation depth by irradiation with two coherent 488 nm Ar + laser beams.
Oscar Khaselev - One of the best experts on this subject based on the ideXlab platform.
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Constant Voltage Anodizing of Mg‐Al Alloys in KOH ‐ Al ( OH ) 3 Solutions
Journal of The Electrochemical Society, 1998Co-Authors: Oscar Khaselev, Joachim YahalomAbstract:Constant voltage anodizing of binary Mg-Al alloys containing 2, 5, 8, and 12% of aluminum was studied. Anodizing was conducted in a bath containing 3 M KOH + 0.6 M KF + 0.21 M Na 3 PO 4 with additions of 0.013, 0.064, 0.13, and 0.4 M of Al(OH) 3 . A thin Amorphous Film was formed during the first stage of anodizing. Prolonged anodizing caused local breakdown and crystallization of the initially formed anodic Films. The chemical composition of the newly formed crystalline Film was determined. The elements in the Film were mainly magnesium, aluminum, and oxygen. Aluminum penetrated into the Film both from the electrolyte and from the Mg-Al alloy substrate. The phase composition of the anodic Films was found to be a mixture of MgO and MgAl 2 O 4 .
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constant voltage anodizing of mg al alloys in koh al oh 3 solutions
Journal of The Electrochemical Society, 1998Co-Authors: Oscar Khaselev, Joachim YahalomAbstract:Constant voltage anodizing of binary Mg-Al alloys containing 2, 5, 8, and 12% of aluminum was studied. Anodizing was conducted in a bath containing 3 M KOH + 0.6 M KF + 0.21 M Na 3 PO 4 with additions of 0.013, 0.064, 0.13, and 0.4 M of Al(OH) 3 . A thin Amorphous Film was formed during the first stage of anodizing. Prolonged anodizing caused local breakdown and crystallization of the initially formed anodic Films. The chemical composition of the newly formed crystalline Film was determined. The elements in the Film were mainly magnesium, aluminum, and oxygen. Aluminum penetrated into the Film both from the electrolyte and from the Mg-Al alloy substrate. The phase composition of the anodic Films was found to be a mixture of MgO and MgAl 2 O 4 .
Hiroshi Ishiwara - One of the best experts on this subject based on the ideXlab platform.
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Epitaxial growth of strain‐free Ge Films on Si substrates by solid phase epitaxy at ultrahigh pressure
Applied Physics Letters, 1992Co-Authors: Hiroshi Ishiwara, Takayoshi Sato, Akira SawaokaAbstract:A novel method to solve the thermal mismatch problem in heteroepitaxial growth has been presented, in which an Amorphous Film deposited on a single‐crystal substrate is grown by solid phase epitaxy at ultrahigh pressure. It has been theoretically predicted in such systems as Ge/Si and GaAs/Si that the difference of the thermal expansion coefficient can be compensated by that of elastic strain generated by hydrostatic pressure. Experimentally, it has been found that the residual strain in Ge Films on Si substrates is linearly decreased with increase of the pressure during annealing, while the defect density in the Film is kept constant. It has been presumed from these results that a strain‐free Ge Film can be grown on a Si substrate by solid phase epitaxy at 2.5 GPa.
