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  • 1
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 77 (1995), S. 1225-1232 
    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
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  • 2
    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
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  • 3
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    International journal of cosmetic science 27 (2005), S. 0 
    ISSN: 1468-2494
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The advantages and disadvantages of oxidative permanent and acid-type semi-permanent hair colors are evident. The former provides a long-lasting ‘permanent’ color, while the latter imparts less damage to the hair. We developed a novel acid-type hair color technology that can allow an acid dye and a metal ion to form a complex inside the hair similar to the oxidative hair color. It is well known that acid dye diffuses into the hair and creates an ionic bond with the positively charged amino acid residues of hair protein. However, the dye can be extracted easily from the hair by daily shampooing due to the weakness of the bond. In order to strengthen this bond and to prevent the extraction of the dye by shampooing, an aluminum chloride ion was chosen as the metal ion component to form the dye–metal complex. A proper composition of penetration enhancers, benzyl alcohol and ethyl alcohol, was required to allow acid dyes to interact with the aluminum chloride ion after each component penetrates deeply into the hair to form a complex inside the hair. To provide color brightness and a color longevity effect to hair color, glycolic acid was also selected due to the observation that a weak acid with a small molecular weight would enhance those effects.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Chester : International Union of Crystallography (IUCr)
    Journal of synchrotron radiation 5 (1998), S. 1013-1015 
    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
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  • 5
    Electronic Resource
    Electronic Resource
    Chester : International Union of Crystallography (IUCr)
    Journal of synchrotron radiation 4 (1997), S. 256-260 
    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
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  • 6
    Electronic Resource
    Electronic Resource
    s.l. ; Stafa-Zurich, Switzerland
    Solid state phenomena Vol. 121-123 (Mar. 2007), p. 545-548 
    ISSN: 1662-9779
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Physics
    Notes: Anomalously high values of power α (1.6 〈 α 〈 12) are found in power laws in conductanceversus energy relationships in carbon-nanotube peapod quantum dots, encapsulating a chain of C60 molecules. Thispower is controllable by the applied back gate voltage. Atomic-like behaviors with doubly degenerate groundstates are also found by single electron spectroscopy. They reveal that a portion of power originates from theTomonaga-Luttinger liquid via the occupied electronic levels, which originate from the subbands unique to thepeapods. This observation also clarify that the encapsulated C60 molecules do not directly contribute to the abovequantum phenomena in peapods
    Type of Medium: Electronic Resource
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  • 7
    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
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  • 8
    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
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  • 9
    Electronic Resource
    Electronic Resource
    s.l. ; Stafa-Zurich, Switzerland
    Materials science forum Vol. 475-479 (Jan. 2005), p. 4191-4194 
    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: The fracture behavior under high-loading velocity and at high temperature wasinvestigated using tensile testing system for a shape memory alloy. Both SEM and X-Ray were used to examined the testing sample before and after tensile testing. It was found that the fracture behavior shows some similar tendency between at high-loading velocity and high-temperature. Based on the results, it can be confirmed that the shape memory alloy can be used to develop high performance intelligent material with high-impact resistance
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 1432-2218
    Keywords: Key words: Laparoscopic cholecystectomy — Gallbladder perforation — Intraabdominal contamination — Spilled gallstones — Complications
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: Gallbladder perforation often occurs during laporoscopic cholecystectomy. Methods: The frequency and causes of gallbladder perforation as well as the relevant clinical background factors were investigated in 110 patients undergoing laparoscopic cholecystectomy. We also evaluated intraperitoneal contamination by bacteria and gallstones at the time of gallbladder perforation and investigated whether perforation caused early or late postoperative complications. Results: Intraoperative gallbladder perforation occurred in 29 of the 110 patients (26.3%). It was caused by injury with an electric knife during dissection of the gallbladder bed, injury during gallbladder retraction with grasping forceps, injury during gallbladder extraction from the abdomen, and slippage of cystic duct clips (potentially causing bile and stone spillage). Perforation was more frequent in patients with positive bile cultures and in those with pigment stones (p 〈 0.02), but not in patients with cholecystitis or cystic duct obstruction. The peritoneal cavity was contaminated by bacteria in 11/29 patients (37.9%) and by spilled stones in 3/29 patients (10.3%). There was no difference in the incidence of postoperative complications between the patients with and without perforation either in the early postoperative period or during follow-up for 24–42 months. Only one patient developed abdominal pain and fever in the early postoperative period, and they were probably related to perforation. Conclusions: Although gallbladder perforation is sometimes unavoidable during laparoscopic cholecystectomy, the risk of severe complications appears to be minimized by early closure of perforation, retrieval of as many of the spilled stones as possible, and intraperitoneal lavage.
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