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The growth of In onto W(1 1 0) was observed at room temperature by means of low-energy electron diffraction and photoemission from core levels and valence levels. Surface diffusion of In onto the W(1 1 0) surface was studied by using ESCA imaging property of SCIENTA ESCA200 instrument at the temperature range of 400-550 K. 相似文献
23.
Lehn WH 《Applied optics》2003,42(3):390-393
Superior mirages of unusual brightness are occasionally observed. Two such cases, photographed over the frozen surface of Lake Winnipeg, Canada, are documented. Visually, these mirages appear as featureless bright barriers far out on the lake. They are just images of the lake ice, yet the luminance in one case was 2.5 times (in the other, 1.7 times) the luminance of the ice surface in front of the mirage. The mirage itself can be modeled by means of a conduction inversion, but a proper explanation of the brightness is not yet available. 相似文献
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Recovery of platinum, tin and indium from spent catalysts in chloride medium using strong basic anion exchange resins 总被引:1,自引:0,他引:1
This work describes a route for platinum recovery from spent commercial Pt and PtSnIn/Al2O3 catalysts using strong basic mesoporous and macroporous anion exchange resins (Cl− form). The catalysts were leached with aqua regia (75 °C, 20-25 min). Platinum adsorption was influenced by the presence of other metals which form chlorocomplexes (tin, indium) and also base metals (aluminum). However, it was possible to overcome this fact by a sequential desorption procedure. Aluminum was selectively removed from the resins by elution with 3 mol L−1 HCl. Platinum was desorbed passing 1 mol L−1 Na2S2O3 (pH 9). Tin was removed by elution with 0.1 mol L−1 ascorbic acid. Indium was removed using 0.1 mol L−1 EDTA as eluent. Desorption efficiency exceeded 99% for all metals. Metals were recovered in high yields (>98 wt%). 相似文献
27.
Alfons Schloemer Waldemar Godbersen und Max Ohm 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1940,79(4):337-344
Zusammenfassung Bericht über die gemeinsame Kontrolle des Groß-Berliner Buttermarktes durch die Kontrollorgane der amtlichen Lebensmittelkontrolle, den Gewerbe-Außendienst der Polizei und die Preußische Landesanstalt zusammen mit den Buttersachverständigen der Hauptvereinigung der deutschen Milch- und Fettwirtschaft, sowie des Milch- und Fettwirtschaftsverbandes Kurmark im Jahre 1939; ambulante Kontrolle, Methodik der polizeilichen Probenahme, Begleitbogen, Prüfung der Butterproben bezüglich Kennzeichnung, Form, Gewicht, Perforierung, Wassergehalt, Verfälschung mit fremden Fetten sowie Sinnenprüfung; Beurteilung der Proben auf Grund der verschiedenen, hier angeführten Gesetze, Verordnungen und Anordnungen. 相似文献
28.
Waldemar Ternes Melanie Gronemeyer Karin Schwarz 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1995,201(6):544-547
p-Cymene-2,3-diol, carvacrol and thymol are components of thyme that exhibit antioxidant activities. The concentration of each substance was determined in different foodstuffs containing thyme extract. The stabilities ofp-cymene-2,3-diol, carvacrol and thymol were examined by heating lard containing thyme extract at temperatures from 80 °C to 160 °C. 相似文献
29.
José María Desantes Vicente Bermúdez Antonio García Waldemar G. Linares 《Aerosol science and technology》2013,47(10):1161-1175
Control strategies such as variations in injection pressure and timing have been used by researchers to reduce in-cylinder exhaust emissions and meet legislation standards. Postinjection has been studied for several years and is now well known as an efficient strategy for reducing soot emission. Diesel gaseous and particle mass emissions have been progressively reduced over the last twenty years as a consequence of increasingly restrictive emission legislation and the application of aftertreatment devices. The main objective of this work is to better understand the effect of postinjection on particle size distribution in diesel exhaust. The approach uses a modern, well-instrumented research engine test cell equipped with a flexible high pressure fuel injection system. The results of this work provide guidelines for developing strategies to reduce particle size distribution in diesel engines. A major improvement in particle size distribution was found in the accumulation mode by using a close postinjection of a small quantity of fuel. For reduction in nucleation mode, a relationship was found with close postinjections of large quantities of fuel. 相似文献
30.
Marcelo Fernandes Cipreste Michele Rocha de Rezende Marlon Luiz Hneda Anderson Maia Peres Alexandre Alberto Chaves Cotta Verônica de Carvalho Teixeira Waldemar Augusto de Almeida Macedo Edésia Martins Barros de Sousa 《Ceramics International》2018,44(15):17800-17811
Hydroxyapatite (HA) nanoparticles (NPs) doped with different radioisotopes for use as theranostic systems play an important role in scientific research nowadays due to their ability to simultaneously act in the treatment and diagnosis of various types of cancers. In this work, we describe the synthesis and characterization of a hydroxyapatite/tenorite nanocomposite functionalized with folic acid, representing a nanotheranostic material with potential for application as an agent in positron emission tomography imaging systems and to act specifically in the treatment and diagnosis of osteosarcoma. 64Cu and 32P were produced by nuclear activation in the TRIGA reactor at CDTN. The obtained samples were characterized by XRD with Rietveld refinement, XAFS, SEM, BET, TGA, FTIR, CHN, ICP-AES, XPS and gamma spectroscopy. We investigated how CuO grows in HA NPs, the stability of the interactions between CuO and HA constituents and the interactions between folic acid and the surface of the HA NPs. The results indicate the formation of a second phase (tenorite) besides hydroxyapatite, and that the interactions between the two phases are stable, resulting in a nanocomposite. Furthermore, the activation of 64Cu and 32P inside the HA matrix, through the exposition to a neutron flux, produces a theranostic material of interest for biological tests. 相似文献