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21.
J. V. Kunzler W. Schreiner A. Bristoti D. E. BrandÃo 《Journal of Thermal Analysis and Calorimetry》1977,11(1):81-86
Saturation magnetization measurements as a function of temperature were performed on Cu2Mn(Al1–xSnx) Heusler alloys to study the existence of stable structures. The derivatograph was applied to study the thermal effects.
Work supported in part by Conselho Nacional de Desenvolvimento Cientifico e Tecnologico and Banco Nacional de Desenvolvimento Economico, Brasil. 相似文献
Zusammenfassung Sättigungsmagnetisierungsmessungen als Funktion der Temperatur sowie Derivatographie wurden an Heusler-Legierungen der Formel Cu2Mn(Al1–xSnx) zu Untersuchungen der Existenz einer stabilen Struktur vorgenommen.
Résumé Etude de l'existence d'une structure stable dans les alliages de Heusler Cu2Mn(Al1–xSnx), à l'aide d'un Derivatograph et par des mesures de magnétisation à saturation en fonction de la température.
XecnepaCu2Mn(Al1–xSnx), , , . .
Work supported in part by Conselho Nacional de Desenvolvimento Cientifico e Tecnologico and Banco Nacional de Desenvolvimento Economico, Brasil. 相似文献
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van den Brand JF Ent R Anthony PL Arnold RG Arrington J Beise EJ Belz JE Bosted PE Bulten H Chapman MS Coulter KP Dietrich FS Epstein M Filippone BW Gao H Gearhart RA Geesaman DF Hansen J Holt RJ Jackson HE Jones CE Keppel CE Kinney ER Kuhn S Lee K Lorenzon W Lung A Makins NC Margaziotis DJ McKeown RD Milner RG Mueller B Napolitano J Nelson J O'Neill TG Papavassiliou V Petratos GG Potterveld DH Rock SE Spengos M Szalata ZM Tao LH van Bibber K Wasson DA White JL Zeidman B 《Physical review D: Particles and fields》1995,52(9):4868-4871
24.
Makins NC Ent R Chapman MS Hansen J Lee K Milner RG Nelson J Arnold RG Bosted PE Keppel CE Lung A Rock SE Spengos M Szalata ZM Tao LH White JL Coulter KP Geesaman DF Holt RJ Jackson HE Papavassiliou V Potterveld DH Zeidman B Arrington J Beise EJ Belz E Filippone BW Gao H Lorenzon W Mueller B McKeown RD O'Neill TG Epstein M Margaziotis DJ Napolitano J Kinney E Anthony PL van Bibber K Dietrich FS Gearhart RA Patratos GG Kuhn SE van den Brand JF Bulten H Jones CE 《Physical review letters》1994,72(13):1986-1989
25.
H. Reuther O. Nikolov S. Kruijer R. A. Brand W. Keune D. Liljequist S. Weber S. Scherrer 《Hyperfine Interactions》1994,92(1):1367-1372
-Fe surfaces were implanted with a nominal dose of 5×1017 Al ions/cm2 at 50 keV and a current density of about 3.7 A/cm2. Samples of different shapes and thicknesses have been used in order to test the influence of heat flow from specimen to target holder during implantation. Integral and energy differential (depth-selective)57Fe conversion electron Mössbauer spectroscopy (CEMS and DCEMS) were employed. The spectra indicated a magnetic phase characterised by a broad hyperfine field distributionP(B
hf), a non-magnetic phase, and -Fe. The relative intensity of the non-magnetic phase was enhanced if the thermal contact during implantation became worse. An energy dependence of DCEM spectra in the L-electron range was observed. Model calculations using L-electron weight functions and experimental concentration profiles obtained by secondary neutral mass spectroscopy (SNMS) yielded fair agreement between calculated and experimental phase signals. The results demonstrate that the non-magnetic Fe-Al alloy phase with high Al concentration is located closer to the surface than the magnetic alloy phase, which extends to much larger depth than expected. 相似文献
26.
F. Kastenholz E. Grell J. W. Bats G. Quinkert K. Brand H. Lanig F. W. Schneider 《Journal of fluorescence》1994,4(3):243-246
Two newly synthesized cryptands act as sensitive Na+- and K+-selective indicators for cation concentrations above 20 M. The fluorescence properties change markedly upon cation binding. In addition, the free ligands exhibit a pronounced sensitivity to pH, which is considerably lower for the cation complexes. Time resolved fluorescence is characterized by a decay time of about 5 ns that is attributed to the diprotonated protolytic state of the uncomplexed ligands. Semiempirical calculations show the systematic influence of the nitrogen lone pairs or the N–H bond on the stability of the system. The cause of the strong fluorescence intensity increase observed upon protonation of the fluorescent cryptands may be attributed to an increase in the S1–T
x
energy gap as a consequence of bridgehead nitrogen protonation.This is a peer-reviewed conference proceeding article from the Third Conference on Methods and Applications of Fluorescence Spectroscopy, Prague, Czech Republic, October 18–21, 1993. 相似文献
27.
Abstract A novel microcombustion technique for carbon isotopic analysis of nanogram amounts of carbon in non-volatile materials based on isotope ratio monitoring (irm) mass spectrometry is described. Liquid or solid samples placed in a quartz sleeve are combusted at 1000°C in a continuous stream of helium and oxygen. CO(2) removed from the carrier gas stream by cryogenic trapping is transferred onto a GC column. Following GC separation, the CO(2) is transferred via an open split to the ion source of a gas isotope ratio mass spectrometer. Reproducibility for samples >25 nmol carbon is <1‰. Problems associated with blanks from various sources and with reproducible deposition of small sample amounts led to variable accuracy, which was dependent on the compound class being analysed. Minimum sample size was in the range from 5 to 10 nmol carbon. Measurements of dissolved organic carbon (DOC) of groundwater from Germany yielded consistent values of δ(13)C = -28.8‰. 相似文献
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30.
Nanosecond fluorescence spectroscopy has been used to study the interaction of 2-anilinonaphthalene with polar solvent molecules which is shown to result in stoichiometric complex formation at low polar solvent concentrations. This is followed by reorientation of the solvent cage when the concentration of polar solvent is high. 相似文献