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Szuppa T.,Friedrich - Schiller University of Jena | Stolle A.,Friedrich - Schiller University of Jena | Ondruschka B.,Friedrich - Schiller University of Jena | Hopfe W.,Fritsch GmbH
Green Chemistry | Year: 2010

The present article reports on the solvent-free dehydrogenation of γ-terpinene (1) in a planetary ball mill affording p-cymene (2) as the predominant reaction product. The influence of various reaction parameters and technical variables on the transformation of 1 has been assessed. Thus, it is shown that KMnO4 can be substituted by other, less-toxic and environmentally-benign oxidation agents (Oxone®, NaIO4, I 2). In most cases the reaction yielded 2 with high selectivities, whereby conversion can be fine-tuned by variation of the oxidant-to-substrate ratio, the rotation frequency νrot, the number of milling balls nball or the type of grinding auxiliary employed. Contrary to particle refinement processes, the size of the milling balls d (constant mass) has no influence on the conversion and chemical yield. © The Royal Society of Chemistry 2010. Source

Szuppa T.,Friedrich - Schiller University of Jena | Stolle A.,Friedrich - Schiller University of Jena | Ondruschka B.,Friedrich - Schiller University of Jena | Hopfe W.,Fritsch GmbH
ChemSusChem | Year: 2010

A new method for the oxidative cleavage of β-pinene (1) yielding nopinone (2) with potassium permanganate as oxidant under solvent-free conditions was established. The reaction was performed in a conventional ball mill with use of a grinding auxiliary. The auxiliary has the ability to sorb liquid reactants such as 1 on its surface to make liquid(s) accessible for mechanical impact. Different reaction parameters and technical variables were assessed concerning their influence on yield and selectivity of 2. Different chemical parameters such as oxidants, grinding auxiliaries, and quantities were investigated. Also tuning parameters including milling time, rotation frequency, and number of milling balls were explored.A solvent-free method for the synthesis of nopinone from the renewable monoterpene β-pinene in a ball mill is evaluated. The envisioned synthesis pathway uses non-hazardous reagents and is performed under ambient, non-inert reaction conditions. The influence of both technical and chemical reaction parameters on conversion, selectivity, and yield is assessed. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Using various reinforcements to tailor plastics properties to specific needs is a widespread approach in the plastics industry. Due to ecological considerations, natural reinforcements like wood particles or natural fibres have been investigated due to their reinforcing potential, but are usually not discussed in terms of processability. Therefore, the aim of this work is to compare a selected processing pathway for lignocellulosic reinforcements in terms of processability and composite properties. Composites were produced via compounding on a co-rotating twin screw extruder and injection moulding. Materials properties like tensile strength and modulus were assessed, as well as the processing specific properties were recorded. We found, that wood particles show a very good ratio between processability and properties, while sisal fibres outperform the other reinforcements in terms of mechanical properties due to their fibrous shape, but also using reinforcements like milled rice husks in composites can be feasible, especially when wood is not a locally available resource. © 2014 Elsevier Ltd. All rights reserved. Source

Fritsch GmbH | Date: 2010-05-21

The invention relates to a device and a method for the automated production of knotted dough products, in particular pretzels. Said device comprises: a shaping table (

Process for the knotting of a dough strand into a desired form, particularly for the knotting of a dough strand into a pretzel form, wherein the dough strand subject to stretching of the dough strand length is knotted around a form element that provides the desired form for a dough strand with larger starting length than the actual length of the dough strand and/or the desired form with an increased form size, whereupon the form element that establishes the desired form is removed, at least partially, so that the dough strand that was placed into the desired form contracts into a final size.

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