A high pressure thermobalance

A high pressure thermobalance was assembled by placing a DuPont Model 950 balance into a stainless steel enclosure. The thermobalance is capable of operation to a maximum pressure (of N₂) to 500 atm and to a maximum temperature of 500°C. Operation of the instrument is illustrated by the thermogravimetric curves of BaBr₂·2H₂O, CuSO₄·5H₂0 and NaHCO₃ at various pres     

Untersuchungen an oxidischen Katalysatoren. XLIV. Beeinflussung des katalytischen Verhaltens modifizierter Zeolithe vom Typ ZSM-5 durch thermische Behandlung

Studies on Oxide Catalysts. XLIV. Modification of the Catalytic Behavior of Modified ZSM-5 Zeolites by Thermal Treatment The catalytic activity, the shape selectivity, and the deactivation behavior of ZSM-5 in paraffin cracking reactions can be regulated by a thermal pretreatment. A minimum of the deactivation rate as a function of zeolite pretreatment time at 600°C found in the hexane cracking could be verified in the methanol conversion reaction to gasoline.     

Infrarotspektroskopische Untersuchung der Wechselwirkung Ni-haltiger Y-Zeolithe mit Kohlenmonoxid

I.R.-Spectroscopic Investigation of the Interaction between Ni-containing Y-Zeolites and Carbon Monoxide By the interaction of CO with reduced NiNaY or NiHY samples adsorbed CO on Ni²⁺ (2 215 cm^?1) and on Ni⁺ (2 085 and 2 095 cm^?1, respectively) and two species of adsorbed Ni(CO)₄ are formed. Ni(CO)₄ is produced in a slow, reversible reaction. Both species are in an equilibrium which is influenced by the acidity of the samples.     

Quinone‐Catalyzed Selective Oxidation of Organic Molecules

Quinones are common stoichiometric reagents in organic chemistry. Para‐quinones with high reduction potentials, such as DDQ and chloranil, are widely used and typically promote hydride abstraction. In recent years, many catalytic applications of these methods have been achieved by using transition metals, electrochemistry, or O₂ to regenerate the oxidized quinone in situ. Complementary studies have led to the development of a different class of quinones that resemble the ortho‐quinone cofactors in copper amine oxidases and mediate the efficient and selective aerobic and/or electrochemical dehydrogenation of amines. The latter reactions typically proceed by electrophilic transamination and/or addition‐elimination reaction mechanisms, rather than hydride abstraction pathways. The collective observations show that the quinone structure has a significant influence on the reaction mechanism and has important implications for the development of new quinone reagents and quinone‐catalyzed transformations.     

Untersuchungen über polykondensierte Trimethinfarbstoffe

Zusammenfassung Es wird die Darstellung höher molekularer Trimethinfarbstoffe der allgemeinen Formel III beschrieben. Die Auftrennung des Farbstoffgemisches erfolgte chromatographisch. Von den einzelnen Farbstoffen wurden die Absorptionsmaxima bestimmt, die sich nur sehr wenig unterscheiden.Herrn Prof. Dr.L. Ebert zum 60. Geburtstag gewidmet.     

The thermolysis of the neocupferron chelates of yttrium and the rare earth elements

The thermolosis curves of the neocupferron chelates of yttnum, lanthanum, cerium(III), cerium(IV). praseodymium, neodymium, samarium and gadolinuim were determined. It was found that the ehelates were stable up to 8o°, with the oxide levels being reached at 460–750°.