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  • Springer  (63)
  • American Institute of Physics (AIP)  (5)
  • American Physical Society (APS)  (5)
  • 2015-2019  (6)
  • 1990-1994  (67)
Publikationsart
Erscheinungszeitraum
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  • 1
    Digitale Medien
    Digitale Medien
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 93 (1990), S. 434-444 
    ISSN: 1089-7690
    Quelle: AIP Digital Archive
    Thema: Physik , Chemie und Pharmazie
    Notizen: The Cs(7P)+H2→CsH (X 1Σ+) (v‘=0,J‘)+H reaction has been studied in a crossed-beam experiment, with electronic excitation of Cs atoms and laser-induced fluorescence detection of CsH products. The Doppler technique has been applied to determine the center of mass angular scattering probability of CsH products, for all rotational levels between 1 and 14 (in v‘=0) and for various values of the collision energy between 0.03 and 0.13 eV. We have used two complementary arrangements of the analysis laser beam: With a "parallel'' arrangement (the laser beam is along the collision axis), the shape analysis of fluorescence profiles leads directly to the angular scattering probability but experimental constraints limit the range of measurements; with a "perpendicular'' arrangement (the laser beam is perpendicular to the collision plane), fluorescence profiles are symmetrical and "forward'' contributions cannot be separated from "backward'' ones. However, extensive shape analyses have been performed with this perpendicular arrangement, since the direction of scattering was determined earlier by recording several profiles with the parallel arrangement. For the title reaction, it is shown unambiguously that, in the center of mass, CsH products scatter preferentially at small angle, in the forward direction with respect to the Cs initial velocity. The angular scattering probability varies with the collision energy but is independent of the rotational level of the product molecule (thus of its recoil velocity). These results are compatible with the harpooning mechanism which was suggested for the reaction.
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 95 (1991), S. 3347-3360 
    ISSN: 1089-7690
    Quelle: AIP Digital Archive
    Thema: Physik , Chemie und Pharmazie
    Notizen: The Cs(7P)+H2→CsH(X 1Σ+)(v‘=0,J‘)+H harpooning reaction has been studied in a crossed-beam experiment, with electronic excitation of Cs atoms and laser-induced fluorescence detection of CsH products performed in a coherent saturation regime. Measurements of reactive cross sections have been achieved as a function of two parameters: The collision energy Ec (0.015≤Ec≤0.15 eV) and the rotational quantum number J‘ of CsH products (0≤J‘≤16, in v‘=0). For Ec=0.09 eV, the total reactive cross sections corresponding to the two 7P fine structure levels of Cs are σ(Cs(7P1/2)+H2)=4.2×10−16 cm2 and σ(Cs(7P3/2)+H2)=10−16 cm2. These cross sections are much smaller than expected for a harpooning reaction. This is interpreted from ab initio potential energy and quantal dynamics calculations which show that the efficiency of the photochemical reaction (Cs atoms in the 7P state) is limited by the quenching processes associated with the underlying potential energy surfaces connected with Cs atoms in the 6S, 6P, 5D, and 7S states. From the present measurements, one deduces that the rate of these quenching processes is larger than 90%. The rotational distributions of products in v‘=0 measured at two collision energies (Ec=0.045 and 0.09 eV) are close to "prior'' statistical distributions, with the same "surprisal.'' The energy dependence of rotationally resolved cross sections (J‘ fixed, Ec variable) confirms the reaction thresholds and shows that there is no potential barrier higher than 0.015 eV on the entrance valley and the exit valley of the reactive system; it is in agreement with the dependence predicted by hemiquantal dynamical calculations performed in the frame of a harpooning model. The uncertainty on the measurement of absolute cross sections is larger than 70%, but of the order of 20% for relative cross sections.
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 101 (1994), S. 3973-3980 
    ISSN: 1089-7690
    Quelle: AIP Digital Archive
    Thema: Physik , Chemie und Pharmazie
    Notizen: Multireference configuration interaction calculations (MRD-CI) were carried out in order to obtain the bending and stretching potential energy curves of several low-lying electronic states of the fluoroformyl radical FCO. The study of interactions between valence and Rydberg states as well as that of the dissociative behavior is included in the investigation.
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 4
    Digitale Medien
    Digitale Medien
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 101 (1994), S. 3981-3988 
    ISSN: 1089-7690
    Quelle: AIP Digital Archive
    Thema: Physik , Chemie und Pharmazie
    Notizen: Results of an ab initio study of the vibrational structure of several electronic spectral systems of FCO are presented. An interpretation of hitherto recorded spectra, as well as a prediction of features of yet unobserved electronic transitions is given. The absorption spectra observed in the uv spectral region are ascribed to the transitions involving the first excited states of 2A' and 2A‘ character. The emission spectrum obtained by Toby and Toby [J. Phys. Chem. 85, 4071 (1981)] is assigned to the transition X 2A'←2 2A‘. Reassignment of some observed vibrational bands is proposed.
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    Springer
    Journal of anesthesia 6 (1992), S. 510-510 
    ISSN: 1438-8359
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 6
    Digitale Medien
    Digitale Medien
    Springer
    European food research and technology 198 (1994), S. 284-286 
    ISSN: 1438-2385
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Die Mineralstoffe und die Aminosäu-rezusammensetzung der Samen von kultiviertemAmaranthus hypochondriacus wurden untersucht. Die Konzentrationen der Mineralstoffe inAmaranthus-Körnern sind ähnlich denen in Weizen oder auch der Erbse. Die Standorte der Pflanzen haben allerdings einen bedeutenden Einfluß. Der Gesamt-Aminosäuregehalt und besonders die Menge der essentiellen Aminosäuren (Lysin, Arginin usw.) sind höher als in den Samen von Weizen und Mais. Die kultiviertenAmaranthus-Arten haben deshalb nicht nur vorteilhafte ökologische (Dürrefestigkeit, Anspruchslosigkeit), sondern auch positive ernährungsphysiologische Eigenschaften.
    Notizen: Abstract The mineral elements and the amino acids in seeds of cultivatedAmaranthus hypochondriacus were studied. The following conclusions can be made: 1. The contents of minerals inAmaranthus seed are similar to those of wheat and (except of a few elements: P, K) of pea. The habitats of plants, especially the soil conditions effect importantly on minerals.-2. The total amino acid content and mainly the rate of essential amino acids (lysine, arginine etc) are higher than those in seeds of wheat and maize and this fact create the importance of cultivation and utilisation of this plant. The cultivatedAmaranthus species have favourable ecological properties (drought resistence, wantlessness) too.
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 7
    Digitale Medien
    Digitale Medien
    Springer
    European food research and technology 193 (1991), S. 36-38 
    ISSN: 1438-2385
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Der Chitingehalt der Fruchtkörper (in einigen Fällen von Hüten und Stielen) einiger höherer Pilzarten aus verschiedenen Standorten von Ungarn wur-de untersucht. Es wurde festgestellt: l. DieAphyllophoraley-Arten, dies sind holzzerstörende, sogenannte xilo-phage Pilze, haben einen niedrigeren Chitingehalt. Die anderen (Boletales, Agaricales, Russulales) Arten zeigen einen signifikant höheren Chitingehalt (etwa 8–9%, bezogen auf Trockenmasse) in den Fruchtkörpern. 2. Die Unterschiede im Chitingehalt der verschiedenen Pilzgruppen werden nicht mit der unterschiedlichen systematischen Zugehörigkeit, sondern mit den verschiedenen Ernährungstypen (holzzerstörende, saprotrophe und Mykorrhizapilze) erklärt. Die holzzerstörenden Pilzarten haben einen signifikant niedrigen, die anderen einen höheren Chitingehalt. 3. Obwohl nur einige Hut- und Stielproben analysiert wurden, wurde in Hüten ein höherer, in Stielen ein niedrigerer Chitingehalt nachgewiesen. 4. Die Chitingehalte der untersuchten Pilzarten sind auch im Hinblick auf die Verdaulichkeit und damit die Verwendbarkeit der einzelnen, häufigen eßbaren Pilzarten bedeutsam.
    Notizen: Summary The chitin content of fruit bodies (in some cases caps and stipes) of some higher fungi from different parts of Hungary have been analysed. The following results were obtained. 1. TheAphyllophorales species which are xilophagous, wood-rotting fungi, have a lower chitin content. The other species (Boletales, Agaricales, Russulales) have a significantly higher (8–9% of dry mass) chitin content in the fruit bodies. 2. The difference in chitin content of systematically different fungal groups can be explained by different types of nutrition (wood-rotting, saprotrophic and mykorrhiza fungi). The wood-rotting species have a significantly lower, the others a higher one. 3. Although only a few cap and stipe samples were analysed, in caps a higher chitin content was found and in stipes a lower one. 4. The chitin content of the in-vestigated fungal species is important information for the digestibility and use of some edible fungi.
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 8
    Digitale Medien
    Digitale Medien
    Springer
    European food research and technology 198 (1994), S. 33-35 
    ISSN: 1438-2385
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung Der Kaliumgehalt von eßbaren höheren Pilzarten beträgt durchschnittlich 34,35 g/kg−1 Trockenmasse (Standardabweichung: 12,91), er ist somit bedeutend und stellt eine wertvolle K-Quelle für die menschliche Ernährung dar. Die Kalium-Konzentration der Pilze ist relativ konstant. Eine Akkumulation von Kalium wird in den Proben nicht gefunden. Diese Tatsache wird durch Ergebnisse anderer Autoren bestätigt.
    Notizen: Abstract The average potassium content of edible higher mushroom species is 34,35 g/kg−1 dry matter (SD:12,91) and thus an important and valuable K-source for human diet. The K-concentration of mushrooms is relatively constant. An accumulation of potassium in the mushroom samples analysed was not found. This fact is confirmed by the results of other authors, too.
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 9
    Digitale Medien
    Digitale Medien
    Springer
    European food research and technology 196 (1993), S. 224-227 
    ISSN: 1438-2385
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Beschreibung / Inhaltsverzeichnis: Zusammenfassung In einer Analysenserie wurden die Rohprotein-, Rohasche-, P-, K- und Ca-Gehalte von 57 Proben der 8 eßbaren, häufigen Pilzarten verglichen. Nelken-Schwindling und der Nebelgraue Rötelritterling sind wichtige Proteinquellen, die Pilze aus der FamilieBoletaceae bilden eine Mittelgruppe, relativ proteinarm sind Hallimasch und Herbsttrompete. Den niedrigsten Proteingehalt wies der Pfifferling auf. Der Aschegehalt schwankt in breiteren Konzentrationsgrenzen. Eindeutig wurden besonders hohe P-Gehalte bei den Arten Nebelgrauer Rötelritterling, Nelken-Schwindling nachgewiesen; die Mehrheit der Arten enthalten 6–7 g Phosphor/kg. Die Pilzarten enthalten durchschnittlich 30–40 g/kg Kalium und 0,2–0,3 g/kg Calcium.
    Notizen: Abstract A comparative analysis of crude protein, crude ash, phosphorus (P), potassium (K) and calcium (Ca) contents of 57 samples of eight common edible mushroom species was made. The most important protein sources were:Marasmius oreades andLepista nebularis. Species of theBoletaceae formed an intermediate group, while relatively proteinless species were:Armillariella mellea andCratarellus cornucopioides. The lowest crude protein content was established inCantharellus cibarius. The ash contents varied more widely. The greatest P contents were measured inLepista nebularis andMarasmius oreades but most mushrooms contained 6–7 gP/kg. The analysed mushroom samples contained 30–40 gK/kg dry weight and 0,2–0,3 gCa/kg. These analyses are important from the point of view of the nutritional role of mushrooms.
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 10
    Digitale Medien
    Digitale Medien
    Springer
    The European physical journal 340 (1991), S. 51-57 
    ISSN: 1434-601X
    Schlagwort(e): 25.40.−h
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Physik
    Notizen: Abstract The production ofη-mesons in proton-nucleus reactions is analysed with respect to primary nucleon-nucleon (NN→NNη) and secondary pion-nucleon (πN→ηN) production processes on the basis of Hartree-Fock groundstate momentum distributions and free on-shell production processes. The folding model adopted compares well for meson production with more involved simulations based on VUU transport equations. Similar to K+ production in proton-nucleus reactions theη-mesons are primarily produced by theπN →ηN channel. However,η-mesons are absorbed in nuclei via excitation of the N* (1535) resonance which leads to strong distortions of the primordial spectra. On the other hand, the experimental mass dependence of the differential cross sections might yield information about the in-medium properties of this resonance.
    Materialart: Digitale Medien
    Standort Signatur Einschränkungen Verfügbarkeit
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