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
  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 104 (1971), S. 2475-2482 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A New Method for the Preparation of 1.2-Dicarbonyl CompoundsThe dehydrogenation of α-aminoketones with mercuric acetate or mercuric complexes gives 1.2-dicarbonyl compounds in mostly good yields.
    Notes: Die Dehydrierung von α-Aminoketonen mit Quecksilber(II)-acetat bzw. Quecksilber(II)-Komplexen führt in meist guten Ausbeuten zu 1.2-Dicarbonylverbindungen.
    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 431 (1977), S. 134-143 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Polymorphism of Perovskite Compounds Ba2SE0.67WVIO6. II. The Systems Ba2Nd0.67(1-x)Y0.67xWO6 and Ba2Nd0.67W1-xUxO6In the system Ba2Nd0.67(1-x)Y0.67xWO6 the formation of a continuous series of mixed crystals with cubic 1:1 ordered perovskite structure is observed. The existence of a hexagonal modification is confined to the Y-rich side (x ≥ 0,9). In the Ba2Nd0.67W1-xUxO6 series only for x ≤ 0,25 homogeneous cubic perovskites are obtained. In contrast to systems with other rare earths the Nd series show uncommon optical properties.
    Notes: Im System Ba2Nd0,67(1-x)Y0,67xWO6 wird die lückenlose Bildung von Mischkristallen mit kubischer 1:1 geordneter Perowskitstruktur beobachtet. Die Existenz einer hexagonalen Modifikation ist auf die Y-reiche Seite (x ≥ 0,9) beschränkt. In der Reihe Ba2Nd0,67W1-xUxO6 können einheitliche kubische Perowskite allein für x ≤ 0,25 erhalten werden. Im Gegensatz zu Systemen mit anderen Seltenen Erden zeichnen sich die Nd-Reihen durch ungewöhnliche optische Eigenschaften aus.
    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 424 (1976), S. 211-228 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Perovskite Phases of the System Ba2Y0,67U1-xWxO6A solid solution series is formed between the polymorphic perovskites Ba2Y0.67UO6 and Ba2Y0.67WO6 (cubic: a = 8.372 Å; hexagonal: a = 4× 5.881 Å and c = 4× 7.778 Å). The structure is cubic between x = 0.1 and 0.99 and for x 〉 0.95 hexagonal as well. Strong deviations from the ideal behaviour are detectabel with spectroscopic methods. The shape of the UO6 and WO6 octahedrons experiences only minor changes within the series.
    Notes: Die polymorphen Perowskite Ba2Y0,67UO6 und Ba2Y0,67 WO6 (kubisch: a = 8,372 Å; hexagonal: a = 4× 5,881 Å und c = 4× 7,778 Å) bilden Mischkristalle. Diese kristallisieren zwischen x = 0,1 und 0,99 kubisch und für x 〉 0,95 ebenfalls hexagonal. Mit spektroskopischen Methoden sind starke Abweichungen vom idealen Verhalten feststellbar. Die Gestalt der UO6- und WO6-Oktaeder erfährt innerhalb der Mischkristallreihe nur geringfügige Änderungen.
    Additional Material: 13 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 425 (1976), S. 175-179 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Polymorphism of Tungsten Perovskite Compounds Ba2SE0,67WO6The compounds Ba2SE0,67WO6 with SE = Gd—Lu are polymorphic. Above 1200°C the instable cubic modification (ordered perovskit with 4 formula units Ba2SE0,67□0,33WO6 per cell) transforms irreversibly into a hexagonal modification with completely filled cationic lattice. For Ba2Eu0,67WO6 the transformation is incomplete. With SE = Nd and Sm only the cubic modification is formed.
    Notes: Die Verbindungen Ba2SE0,67WO6 mit SE = Gd—Lu sind polymorph. Die instabile kubische Modifikation (geordneter Perowskit mit 4 Formeleinheiten Ba2SE0,67□0,33WO6 pro Zelle) wandelt sich oberhalb 1200°C irreversibel in eine hexagonale Modifikation mit aufgefülltem Kationengitter um. Bei Ba2Eu0,67WO6 ist die Umwandlung unvollständig. Mit SE = Nd und Sm konnte allein die kubische Modifikation erhalten werden.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 437 (1977), S. 197-202 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Vibrational Spectroscopic Investigation on Perovskite Type Variants Ba2B0.67III□0.33MVIO6 and their Solid Solutions with Ba2BIIMVIO6In the perovskite typ variants Ba2B0.67III□0.33MVIO6 with MVI = W, U, Te several kinds of MVIO6 octahedra are to distinguish. The study of the solid solutions Ba2B1-xIIY0.67x□0.33xWO6 (BII = Mg, Ca) shows, that in the lattice no more than three different types of WO6 octahedra can be present.
    Notes: Die Perowskitvarianten Ba2B0,67III□0,33MVIO6 mit MVI = W, U, Te enthalten mehrere Sorten an MVIO6-Oktaedern. Aus der Untersuchung der Mischkristallsysteme Ba2B1-xIIY0,67x□0,33xWO6 (BII = Mg, Ca) geht hervor, daß im Gitter nicht mehr als drei verschiedene Typen von WO6-Oktaedern vorhanden sein können.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Vibrational Investigations on Ordered Perovskites A2IIBMO6. I. MO6 Octahedra: Symmetry, Force Constants, and DistancesAccording to their vibrational spectra the ordered perovskites A2IIBMO6 can be divided in three groups: compound with 1. MO6 octahedra of symmetry Oh, 2. MO6 octahedra of lowered point symmetry, 3. different kinds of MO6 octahedra. The force constants, M—O distance and bond order are calculated.
    Notes: Die geordneten Perowskite A2IIBMO6 Können auf Grund ihrer Schwingungs-spektren in 3 Gruppen eingeteilt werden: Verbindungen mit 1. MO6-Oktaedern der Symmetrie Oh, 2. MO6-Oktaeder mit erniedrigter Punktsymmetrie, 3. mit verschiedenen Sorten an MO6-Oktaedern. Die Kraftkonstanten, M—O-Abstände und Bindungsgrade werden berechnet.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Macromolecular Chemistry and Physics 199 (1998), S. 273-282 
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: 2,2-Dibutyl-2-stanna-1,3-dioxacycloalkanes were prepared from dibutyltin oxide and 1,2-ethanediol, 1,3-propanediol or 1,4-butanediol. These tin heterocycles reacted stoichiometrically with double molar amounts of γ-thiobutyrolactone by a stepwise insertion. In contrast to γ-thiobutyrolactone an excess of γ-thiocaprolactone resulted in additional insertion steps, i.e., polymerization of the thiolactone. Analogous insertion reactions were performed with a spirocyclic stannoxane derived from pentaerythritol. With ε-caprolactone macrocyclic polymerization took place without stoichiometric intermediates. When the 2,2-dibutylstanna-dioxepane was reacted with an equimolar amount of 1,3-dithian-2-one, the insertion step was immediately followed by a ring contraction reaction yielding 2-stanna-1,3-dithiane and trimethylene carbonate which polymerized immediately. The application of this reaction sequence to macrocyclic stanna poly(ε-caprolactone) yielded tin-free macrocycles along with 2,2-dibutyl-2-stanna-1,3-dithiane. This reaction sequence allows the synthesis of nontoxic, biodegradable macrocyclic polyesters.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Perovskite Phases in the Systems AO—SE2O3—UO2,x with A = Alkaline Earth Metal and SE = Rare Earths, La, and Y. VIII. The Systems Ba2CaUO6—Ba2Gd0.67UO6 and Ba2CaUO6—Ba2Y0.67UO6The ordered perovskite Ba2CaUO6 forms a solid solution series with Ba2Gd0.67UO6 and Ba2Y0.67UO6, respectively. The deviations from the ideal behaviour are studied by x-ray, diffuse reflectance and vibrational methods.
    Notes: Der geordnete Perowskit Ba2CaUO6 bildet mit Ba2Gd0,67UO6 bzw. Ba2Y0,67UO6 eine lückenlose Mischkristallreihe. Die Abweichungen vom idealen Verhalten werden röntgenographisch und an Hand der diffusen Reflexions- und Schwingungsspektren untersucht.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 431 (1977), S. 144-152 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On Ordered Perovskites with Cationic Defects. The Systems Ba2MgWO6—Ba2Y0.67WO6 and Ba2CaWO6—Ba2Y0.67WO6The perovskites Ba2MgWO6 and Ba2CaWO6 show complete miscibility with Ba2Y0.67WO6. The mixed crystals have a cubic 1:1 ordered perovskite structure, whereas with x an increase of cationic defects is observed (systems Ba2B1-xIIY0.67x□0.33xWO6). Depending on the occupation of the neighbouring positions different types of WO6 octahedra are present. The transformation cubic → hexagonal, which is characteristic for Ba2Y0.67WO6, is oppressed by the incorporation of BII ions.
    Notes: Die Perowskite Ba2MgWO6 bzw. Ba2CaWO6 zeigen mit Ba2Y0,67WO6 vollständige Mischbarkeit. Die in einem kubischen 1:1 geordneten Perowskitigitter kristallisierenden Mischkristalle enthalten mit x steigende Mengen an Kationenfehlstellen (Systeme Ba2B1-xIIY0,67x □0,33xWO6). In Abhängigkeit von den Nachbarschaftsverhältnissen liegen verschiedene Typen an WO6-Oktaedern nebeneinander vor. Die für Ba2Y0,67WO6 charakteristische Umwandlung kubisch → hexagonal wird durch Einbau von BII-Ionen unterdrückt.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 439 (1978), S. 250-254 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the System Ba2Gd2/3□1/3U1-xWxO6 and Hexagonal Perovskites of an 18-Layer TypeIn the system Ba2Gd2/3□1/3U1-xWxO6 the formation of a continuous solid solution series is observed. With x ≤ 0.9 the mixed crystals have a cubic 1:1 ordered perovskite structure. With x ≥ 0.95 the compounds are polymorphic: besides an cubic 1:1 ordered perovskite type for x = 0.95; 0.99 and 1.00 one hexagonal layer structure exists. This lattice is in all cases rhombohedral (space group R3m) and represents an 18 L-type. Likewise the compounds Ba2B2/3III□1/3WVIO6 with BIII = Tb-Lu and Y belong to the 18 L-type.
    Notes: Im System Ba2Gd2/3□1/3U1-xWxO6 wird lückenlose Mischbarkeit beobachtet. Für x ≤ 0,9 kristallisieren die Mischkristalle in einem kubischen 1:1 geordneten Perowskitgitter. Für x ≥ 0,95 tritt Polymorphie auf: neben den kubischen 1:1 geordneten Perowskittyp wird mit x = 0,95; 0,99 und 1,00 eine hexagonale Stapelvariante beobachtet. Dieses Gitter ist jeweils rhomboedrisch (Raumgruppe R3m) und stellt eine 18-Schichtenstruktur dar. Die Verbindungen Ba2B2/3III□1/3WVIO6 mit BIII = Tb-Lu und Y besitzen ebenfalls eine 18-Schichtenstruktur.
    Additional Material: 3 Tab.
    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...