Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Inorganic Chemistry  (3)
  • 72.20.Fr  (1)
Material
Years
Keywords
  • 1
    ISSN: 1432-0630
    Keywords: 72.20.Fr ; 72.20.Ht ; 72.20.My ; 73.40.Lq
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract The transport properties of warm and hot electrons in selectively dopedn-Al x Ga1−x As/GaAs heterostructures created by electric fields up to 500 V/cm were studied by Hall effect, conductivity, and Shubnikov-de Haas measurements at lattice temperatures from 4.2 to 300 K. Hall measurements revealed a substantial decrease of electron mobility and also of sheet electron concentration at 77 K with enhanced electric field. The accelerated 2D electrons are partly scattered into the low-mobility first excited (E 1) subband, and they are partly trapped in immobile states located in the AlxGa1−xAs near the interface. Consequently, two differentv(E) characteristics were obtained at 77 K. The 2D electrons populating only the lowest (E 0) subband exhibit a velocity of v∼-2×107 cm/s at 500 V/cm, while the averaged velocity due to all electrons reaches a value of v∼-1.5×107cm/s at 500 V/cm. The analysis of the Shubnikov-de Haas oscillations and Fast Fourier transformation of the data manifested that the 2D electrons are very rapidly accelerated at 4.2 K and achieve electron temperatures much higher than the lattice temperature at electric fields as low as 1 V/cm. The major cooling process for these electrons is scattering into the low-mobilityE 1 subband.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 338 (1965), S. 37-46 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Due to spectroscopic studies, the intermediates in the formation of the salts [Fe(L)6] [Fe4(CO)13], which are formed in the systems Fe(CO)5/pyridin and Fe(CO)5/morpholine, are probably soluble salts of the anions [Fe3(CO)11]2- (L = pyridine) and [Fe(CO)4]2- and [Fe3(CO)11]2- (L = formylmorpholine). In the systems Fe3(CO)12/ethylenediaminehydrate and Fe3(CO)12/liquid ammonia the hendecacarbonyltriferrate anion is converted at higher temperature to the octacarbonyldiferrate anion: 3[Fe(L)x][Fe3(CO)11] → 4[Fe(L)x][Fe2(CO)8] + 5 CO (x = 3, L = ethylenediamine; x = 6, L = ammonia).In the reaction of triiron-dodecacarbonyl with ethanol, salts of the hydrogenhendecacarbonyltriferrate are formed; according to the overall reaction 6 Fe3(CO)12 → [Fe(Alk.)x][Fe3(CO)11H]2 + 10 Fe(CO)5 + Fe(OC2H5)2. When the reaction temperature is raised these salts decompose completely yielding Fe(CO)5, instable Fe(OC2H5)2, CO and H2. Also with acetone Fe3(CO)12 reacts to [Fe(CO)11H]-
    Notes: Mit Hilfe der bekannten Absorptionsspektren mehrkerniger Carbonylferrate werden die früher präparativ untersuchten Reaktionen der Eisencarbonyle mit N- und O-Basen beobachtet, um näheren Einblick in den jeweiligen Reaktionsverlauf zu erhalten. In den Systemen Eisenpentacarbonyl/Pyridin oder Morpholin bilden sich die schwer löslichen Salze [Fe(L)6][Fe4(CO)13] wahrscheinlich über die Anionen [Fe3(CO)11]2- (L = Pyridin) bzw. [Fe(CO)4]2- und [Fe3(CO)11]2- (L = Formylmorpholin). In den Systemen Eisentetracarbonyl/Äthylendiaminhydrat oder flüss. Ammoniak wird bei Steigerung der Reaktionstemperatur das 3kernige Salz zum 2kernigen abgebaut, entsprechend 3[Fe(L)x][Fe3(CO)11] → 4[Fe(L)x][Fe2(CO)8] + 5 CO (x = 3. L = Äthylendiamin; x = 6, L = Ammoniak).Im abgeschlossenen System Eisentetracarbonyl/Äthylakohol erhält man nach spektroskopischen Untersuchungen über Teilvorgänge und Alkoholyse das lösliche Hydrogenhendekacarbonyltriferrat, gemäß der Bruttogleichung 6 Fe3(CO)12 \documentclass{article}\pagestyle{empty}\begin{document}$$ 3[{\rm Fe(L)}_{\rm x}][{\rm Fe}_{\rm 3} ({\rm CO})_{11}] \to 4[{\rm Fe(L}_{\rm x} {\rm)}][{\rm Fe}_{\rm 2} ({\rm CO})_8 + 5{\rm CO}] $$\end{document} [Fe(Alk.)x][Fe3(CO)11H]2 + 10 Fe(CO)5 + Fe(OC2H5)2, das sich bei höherer Temperatur vollständig in Fe(CO)5, labiles Fe(OC2H5)2, CO und H2 zersetzt. Auch im System Fe3(CO)12/Aceton bildet sich das Ion [Fe3(CO)11H]-.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 338 (1965), S. 32-36 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The absorption spectra of the polynuclear carbonylferrate anions have been investigated in alkaline-water solution. The solution of the anions [Fe(CO)4H]- and [Fe2(CO)8]2- are not stable and decompose by irradiation with UV light giving the anion [Fe3(CO)11]2-. The hydrogentridecacarbonyltetraferrate-anion [Fe4(CO)13H]- has been also characterized by its absorption spectrum.
    Notes: Die früher beschriebenen Absorptionsspektren mehrkerniger Carbonylferrate in alkalisch-wäßriger Lösung wurden einer Überprüfung unterzogen. Reine Hydrogentetracarbonylferrat- und Oktacarbonyldiferrat-Lösungen mit den Anionen [Fe(CO)4H]- und [Fe2(CO)8]2- erhält man nur unter Rotlicht, während beim Bestrahlen mit UV-Licht z. T. Oxydation über [Fe3(CO)11]2- bis zum Fe(OH)2 erfolgt. Erstmals wurde auch das Hydrogentridekacarbonyltetraferrat-Ion [Fe4(CO)13H]- durch sein Absorptionsspektrum charakterisiert.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 339 (1965), S. 224-224 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No. Abstract.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...