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  • 1
    Electronic Resource
    Electronic Resource
    Photoluminescence studies in CuAlSe2 epilayers grown by low-pressure metalorganic chemical-vapor deposition (1995)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 77 (1995), S. 1225-1232 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Low-temperature photoluminescence (PL) spectra were investigated for CuAlSe2 epilayers grown on GaAs(001) substrates by means of low-pressure metalorganic chemical-vapor deposition. PL properties were studied with relation to metalorganic precursors used for the growth. High-quality undoped epilayers exhibited PL peaks related to a free exciton (2.739 eV) and a bound exciton (2.677 eV). The other undoped epilayers exhibited PL bands at 2.3, 2.4, and 2.5 eV originating from donor-acceptor (D-A) pair recombinations. Some of them were found to have a common activation energy for the thermal quenching of 50±10 meV. The PL spectrum changed drastically by impurity doping. Intense green emissions at 2.51 and 2.43 eV were observed in Zn and Mg-doped epilayers, respectively, which were interpreted as D-A pair recombinations based on the dependencies of the PL spectra on excitation intensity, decay time, and temperature. The donor and the acceptor activation energies (ED and EA) were estimated to be 110 and 230 meV, respectively, for the Zn-related D-A pair emission at 2.51 eV. Similarly, ED and EA for CuAlSe2:Mg were estimated to be 140±10 and 270±10 meV, respectively. Furthermore, D-A pair recombinations between 2.3 and 2.5 eV for CuAlSe2:I were studied. CuAlSe2 was proven to be a promising material for short-wavelength visible-light-emitting devices. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.358990
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  • 2
    Electronic Resource
    Electronic Resource
    Preparation and characterization of CuAlxGa1−xSe2 alloy layers grown by low-pressure metalorganic vapor phase epitaxy (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 80 (1996), S. 3338-3345 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: CuAlxGa1−xSe2 alloy layers were successfully grown on GaAs(001) by low-pressure metalorganic vapor phase epitaxy. The distribution coefficient of Al was unity. All alloy layers had their c-axis normal to the substrate plane. Exciton resonance energies were determined as a function of x by means of photoreflectance measurements. A quadratic dependence of exciton energies on x was confirmed. The spin-orbit splittings of the epilayers were approximately the same as that of bulk crystals. The magnitudes of crystal-field splittings were larger than that of bulk crystals, and this was explained in terms of residual tensile biaxial strain in the epilayers. The color of the low-temperature photoluminescence (PL) changed from red to crimson, orange, yellow, green, and bluish-purple with increasing x. A peak due to a free-to-acceptor transition was dominant in the PL spectra of the alloy layers. The acceptor ionization energy increased with increasing x, and the result may reflect an increase of the hole effective mass. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.363245
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  • 3
    Electronic Resource
    Electronic Resource
    Interfacial fatigue crack propagation in Ni-base superalloy protective coatings (2001)
    Oxford, UK : Blackwell Science Ltd
    Fatigue & fracture of engineering materials & structures 24 (2001), S. 0 
    Details
    ISSN: 1460-2695
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: It is important to control the interface strength of coatings and composite materials; a feature that has been noted for many years. However, how can interface strength be evaluated and controlled? In order to explore this aspect, subcritical fatigue crack growth behaviour was investigated along the interface of a CoNiCrAlY coated Ni-Base superalloy. According to the traditional fatigue test methodology, fatigue crack propagation tests were carried out, using double cantilever beam specimens. The resistance to the fatigue crack propagation was successfully evaluated by a fracture mechanics approach. Particular attention was given to the effects of surface finish of the substrate as a coating parameter, the test temperature, and long-term thermal ageing after the coating.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1460-2695.2001.00452.x
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  • 4
    Electronic Resource
    Electronic Resource
    Immunohistochemical localization of CEA, CA19-9 and DU-PAN-2 in hepatitis C virus-infected liver tissues (2002)
    Oxford UK : Blackwell Science Ltd
    Histopathology 40 (2002), S. 0 
    Details
    ISSN: 1365-2559
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Immunohistochemical localization of CEA, CA19-9 and DU-PAN-2 in hepatitis C virus-infected liver tissues Aims: We investigated expression of CEA, CA19-9 and DU-PAN-2 in liver tissues of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma, measuring their serum value to clarify their clinical significance, and proliferating cell nuclear antigen (PCNA) was assessed in serial sections to determine whether expression of these molecules in chronic liver disease was related to regeneration of biliary ducts. Methods and results: Liver tissues were biopsied under peritoneoscopy or echo-guidance and resected surgically among 63 patients with anti-hepatitis C virus-positive sera. There were 26 cases of chronic hepatitis, 21 cases of liver cirrhosis and 16 cases of hepatocellular carcinoma (four cases of mixed type). They were simultaneously used for immunocytochemistry for CEA, CA19-9 and DU-PAN-2, and PCNA was demonstrated in serial liver tissues by immunohistochemistry. Serum CEA, CA19-9 and DU-PAN-2 were measured by radioimmunoassay or enzyme immunoassay. In chronic hepatitis and liver cirrhosis CEA immunoreactivity was seen on membranes facing bile canaliculi and in bile ductules. Both CA19-9 and DU-PAN-2 immunoreactivity were observed in bile ductules in chronic hepatitis liver cirrhosis and non-neoplastic areas surrounding hepatocellular carcinoma, and CA19-9 was also present in interlobular bile ducts. PCNA immunoreactivity was not detected in marker-positive bile ductules or interlobular bile ducts. In hepatocellular carcinoma CEA immunoreactivity was seen on membrane facing dilated bile canaliculi in glandular structures, and CEA, CA19-9 and DU-PAN-2 immunoreactivity was observed in cholangiolar areas in mixed type of hepatocellular carcinoma. Conclusions: CEA in chronic hepatitis and liver cirrhosis is expressed not only in bile ductules but also on membrane facing bile canaliculi, and both CA19-9 and DU-PAN-2 were seen in different levels of biliary ducts. These molecules were expressed in bile ductules in surrounding non-neoplastic areas of hepatocellular carcinoma, and their expression was not associated with regeneration of biliary ducts. CEA expression was present in the trabecular type of hepatocellular carcinoma, and CA19-9 and DU-PAN-2 were observed in cholangiolar areas in mixed type of hepatocellular carcinoma.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2559.2002.01374.x
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  • 5
    Electronic Resource
    Electronic Resource
    Spectrometer for polarized soft X-ray Raman scattering (1998)
    Chester : International Union of Crystallography (IUCr)
    Journal of synchrotron radiation 5 (1998), S. 1013-1015 
    Details
    ISSN: 1600-5775
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences , Physics
    Notes: An experimental system for polarized soft X-ray Raman scattering spectroscopy has been constructed. The soft X-ray spectrometer is based on the Rowland circle geometry with a holographic spherical grating. Three types of gratings are used to cover the energy range from 18 eV to 1200 eV. According to a ray-trace simulation, the resolution is expected to be 200 meV at 700 eV by using a 10 µm slit width. The polarized and depolarized soft X-ray Raman scattering spectra can be measured by rotating the soft X-ray spectrometer around the axis of the incident beam. Preliminary measurements of polarized and depolarized spectra were accomplished at undulator beamline BL-2C of the Photon Factory.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0909049597019481
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  • 6
    Electronic Resource
    Electronic Resource
    Serration Phenomenon in High Purity Chromium (2004)
    s.l. ; Stafa-Zurich, Switzerland
    Materials science forum Vol. 449-452 (Mar. 2004), p. 269-272 
    Details
    ISSN: 1662-9752
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Serration phenomenon of sintered and cast chromium was investigated by means of tension test at various strain rates. With increasing test temperature, tensile strength decreased gradually at first and showed a minimum at a certain temperature. Above this temperature, the strength continued to increase to a maximum value. Serrated flow appeared between the temperatures of the minimum and maximum tensile strengths. Tensile ductility minimum was also observed around the temperature of the maximum tensile strength. Relation between the strain rate and the temperature T of the maximum tensile strength could be well described by an Arrhenius equation. Activation energy of 101.3kJ/mol found in the present study is in good agreement with the activation energy for diffusion of nitrogen atom in chromium
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/02/08/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.449-452.269.pdf
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  • 7
    Electronic Resource
    Electronic Resource
    Improvement of Inner Surface for Machine Parts by Shot Peening (2004)
    s.l. ; Stafa-Zurich, Switzerland
    Materials science forum Vol. 449-452 (Mar. 2004), p. 345-348 
    Details
    ISSN: 1662-9752
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Shot peening process of inner surface of machine parts in which rebound shots collide with the inner surface was investigated. The jig used for rebound shot peening has the surface with a slope to the inner surface of machine parts, and the collision direction of shots was vertical to the inner surface. In this process, a compressed air type shot peening machine was employed. The influence of processing conditions was evaluated by the distributions of hardness, residualstress and surface roughness in the test pieces of pipes and coiled springs. The effect of shot peening increases with the increase of shots collision energy. A stress peening process for inner surface of coiled springs using rebound shots was also performed. The coiled spring was provided higher compressive residual stresses. The results of a fatigue test showed that the fatigue life of the spring was improved. The compressive residual stress reduces the tensile stress of coiled spring. It was found that the present process was suitable for improving the inner surface of machine parts
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/02/08/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.449-452.345.pdf
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  • 8
    Electronic Resource
    Electronic Resource
    Relaxation Process of the Excited State and Selection Rule in the Soft X-ray Emission of Si and cBN (1997)
    Chester : International Union of Crystallography (IUCr)
    Journal of synchrotron radiation 4 (1997), S. 256-260 
    Details
    ISSN: 1600-5775
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences , Physics
    Notes: The soft X-ray emission spectra of Si and cubic boron nitride (cBN) are compared in the Si2p- and B1s-core exciton regions because inversion symmetry is lost and the band gap is extremely large for cBN although both crystal structures are very similar. The background in the soft X-ray emission spectrum of Si is much larger than that for cBN but becomes extremely weak as the excitation energy becomes low and the Raman process becomes dominant compared with the fluorescence process. The background is found to be mainly formed by electron excitation from the valence band to the conduction band. The Raman spectrum is similar to the absorption spectrum in cBN, while those of Si are quite different from each other. It is shown that the centrosymmetry is important in the selection rule of Raman scattering. In resonant Raman scattering the selection rule partly breaks down due to the lattice relaxation process that emits an ungerade phonon in the intermediate state.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0909049597001143
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  • 9
    Electronic Resource
    Electronic Resource
    Increased migration of neutrophils to granulocyte-colony stimulating factor in rat carrageenin-induced pleurisy: Roles of complement, bradykinin, and inducible cyclooxygenase-2 (1996)
    Springer
    Inflammation research 45 (1996), S. 335-346 
    Details
    ISSN: 1420-908X
    Keywords: Granulocyte colony-stimulating factor ; Neutrophil migration ; Complement ; Kinin ; Cyclo-oxygenase-2
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Administration of human recombinant granulocyte colony-stimulating factor (G-CSF, 100 μg/kg/day, s.c) to rats for 4 days significantly increased circulating neutrophil counts (by 1130%), together with an increase in mononuclear leukocyte counts (by 119%). Infiltrated pleural neutrophil counts in G-CSF-treated rats (G-CSF-r) 5h after the intrapleural injection of zymosanactivated serum were significantly higher (by 155%) than those in control rats (Vehicle-r). In carrageenin-induced pleurisy, counts of infiltrated pleural neutrophils in G-CSF-r 5 and 7h after carrageenin were significantly higher (by 119% and 116%) than those in Vehicle-r. G-CSF treatment increased the volume of pleural exudate and the plasma exudation rate by 122% and 226%, compared to values in Vehicle-r 5h after carrageenin. Cobra venom factor (75 μg/kg, i.v.) significantly reduced pleural neutrophil migration in G-CSF-r (by 53%) and Vehicle-r (by 49%). Bromelain (10 mg/kg, i.v.) and aspirin (100 mg/kg, p.o.) reduced pleural neutrophil migration and reduced exudate volume and plasma exudation. Intrapleural bradykinin-(1–5) and prostaglandin E2 levels were significantly higher in G-CSF-r than in Vehicle-r. The increased neutrophil migration in G-CSF-r may be atributed to enhanced activation of the complement system facilitated by increased plasma exudation due to bradykinin and prostaglandins.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02252946
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  • 10
    Electronic Resource
    Electronic Resource
    Possible background mechanisms of the effectiveness of cyclooxygenase-2 inhibitors in the treatment of rheumatoid arthritis (1998)
    Springer
    Inflammation research 47 (1998), S. 107-111 
    Details
    ISSN: 1420-908X
    Keywords: Key words: Carrageenin pleurisy — NS-398 — Proliferative inflammation — Angiogenesis — Gastric ulcer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract. Cyclooxygenase (COX)-2 was induced in an acute exudative inflammatory model (rat carrageenin-induced pleurisy) in which prostaglandin E2, 6-keto-prostaglandin F1α, and thromboxane B2 were generated in the pleural fluid. Selective COX-2 inhibitors, such as NS-398, inhibited the plasma exudation and generation of prostaglandin E2, but not that of thromboxane B2 and 6-keto-prostaglandin F1α, in the pleural fluid. In proliferative inflammatory models, COX-2 was induced, and selective COX-2 inhibitors suppressed granuloma formation, particularly, microvessel formation. COX-2 was induced during angiogenesis in a sponge model implanted into skin of rat, and the COX-2 inhibitor suppressed the angiogenesis. As induction of COX-2 was reported in osteoblasts, COX-2 was involved in most characteristic responses of acute exudative inflammation, granuloma formation, bone resorption, and pain in rheumatoid arthritis. The prevention of these COX-2 responses provides a rationale for the effectiveness of COX-2 inhibitors in the treatment of rheumatoid arthritis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s000110050293
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