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Mulheim (Ruhr), Germany

The Max Planck Institute for Coal Research is an institute located in Mülheim an der Ruhr, Germany specializing in chemical research on coals. It is one of the 80 institutes in the Max Planck Society . Founded in 1912 as the Kaiser Wilhelm Institute for Coal Research in Mülheim an der Ruhr to study the chemistry and uses of coal, it became an independent Max Planck Institute in 1949. Wikipedia.

Amundson L.M.,Purdue University | Gallardo V.A.,Purdue University | Vinueza N.R.,Purdue University | Owen B.C.,Purdue University | And 8 more authors.
Energy and Fuels | Year: 2012

A tandem mass spectrometric method using a commercial linear quadrupole ion trap (LQIT) mass spectrometer and another LQIT coupled with a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer is described for the identification and counting of different oxygen-containing functionalities and alkyl groups in unknown aromatic analytes. A total of 64 aromatic model compounds were evaporated and ionized via positive-mode atmospheric pressure chemical ionization (APCI). Ionization of the model compounds primarily results in the formation of protonated molecules, [M + H] +. In some cases, the molecular radical cation, [M] +•, and/or a fragment ion, [M - H] +, are formed instead. Only in one case, no ions were observed near the m/z value of the molecular ion, and the ion with the greatest m/z value is a fragment ion, [M + H - H 2O] +. Once ionized, the ions were subjected to multiple isolation and collision-activated dissociation (CAD) events until no more fragmentation was observed (up to MS 5). In most cases, all functionalities were sequentially cleaved, one or more at a time, by the CAD events. The type of neutral molecule cleaved and the number of times that it was cleaved facilitate the identification and counting of the functionalities. The method was successfully used in concert with high-performance liquid chromatography (HPLC). The HPLC retention times offer further structural information for the analytes. This methodology benefits the chemical, pharmaceutical, and biofuels industries by facilitating the identification of previously unknown compounds directly in complex mixtures, such as crude products of chemical processes, drug metabolites, and lignin degradation products. © 2012 American Chemical Society. Source

Dorresteijn R.,Max Planck Institute for Polymer Research | Nietzel S.,Max Planck Institute for Polymer Research | Joe D.,Max Planck Institute for Polymer Research | Gerkmann Y.,Max Planck Institute for Polymer Research | And 3 more authors.
Journal of Polymer Science, Part A: Polymer Chemistry | Year: 2014

Micrometer-sized spherical polyurethane supports with a narrow size distribution and adjustable porosity were synthesized via the nonaqueous emulsion polymerization technique. They can be directly used in metallocene-catalyzed olefin polymerization, preventing complex aggregation procedures that are typical for other organic and inorganic supports based on silica or latex particles. The reasonable catalytic activity and study of fragmentation behavior, using various optical techniques, demonstrates the potential applicability of the supports. Copyright © 2013 Wiley Periodicals, Inc. Source

Kovacs K.,University of Szeged | Gaspar A.,Helmholtz Center for Environmental Research | Gaspar A.,Max Planck Institute for Coal Research | Sajgo Cs.,Hungarian Academy of Sciences | And 3 more authors.
European Journal of Mass Spectrometry | Year: 2010

Characterization of humic substances isolated from thermal water and surface water was carried out by elemental analysis and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry. Atomic ratios derived from elemental analysis represented compositional differences of humic substances. Hydrogen-to-carbon and oxygen-to-carbon atomic ratios were also calculated from molecular formulae determined by ultra high-resolution mass spectrometry. The van Krevelen diagram was used to illustrate the bias between the atomic ratios from elemental analysis and mass spectrometry. © 2010 IM Publications LLP. All rights reserved. Source

Reichinger M.,Ruhr University Bochum | Reichinger M.,Sud Chemie AG | Schmidt W.,Max Planck Institute for Coal Research | Narkhede V.V.,Ruhr University Bochum | And 3 more authors.
Microporous and Mesoporous Materials | Year: 2012

Ordered mesoporous materials (OMMs) of 1-dimensional hexagonal and 3-dimensional cubic symmetry of the pore systems were synthesized via well-established soft templating routes starting from precursor solutions of MFI-type zeolites (Silicalite-1, TS-1). The products were characterized by XRD, nitrogen and argon physisorption, DTG/DTA, IR, UV-vis spectroscopy, XANES, TEM, 119Xe NMR, and determination of the pair distribution function (PDF) in order to elucidate their structure, in particular to prove the presence of microporosity in arrays smaller than the coherence lengths of XRD, i.e. in the pore walls. The mesoporosity of the OMMs was well supported by physisorption studies and by TEM while the regularity of the structure was documented by XRD, which also served to exclude the presence of microporous crystalline grains. Instead, microporosity was detected by adsorption/desorption of water on tetrahedrally coordinated Ti-sites (XANES), by 119Xe NMR, by the comparison of the PDF with those of amorphous and of MFI-type solids, and by sequential decomposition of the structure directing agents for meso and micropore systems. From comparison of XRD and physisorption data and from the TEM micrographs, the thickness of the microporous mesopore walls was concluded to be ≈1.5 nm. Therefore, the failure of Ar physisorption to detect pores of sizes typical of MFI structures was attributed to the small micropore volume and the very short pore extension. The structural integrity of OMMs with 1-dimensional hexagonal pore system could be improved by a hydrothermal post-treatment despite the microporous nature of their pore walls, which resulted in more narrow mesopore size distributions peaking at somewhat larger pore sizes. © 2012 Elsevier Inc. All rights reserved. Source

News Article | March 14, 2016
Site: http://cen.acs.org/news/ln.html

Among the elements, cesium, located in the lower left corner of the periodic table, and fluorine, in the upper right corner, are among the largest electropositive and smallest electronegative elements, respectively. When chemists look at possible ways to get the two elements together, something interesting is bound to happen. And it has. Klaus-Richard Pörschke, David Pollak, and Richard Goddard of the Max Planck Institute for Coal Research have prepared a molecule in which a central cesium atom is coordinated by 16 fluorine atoms—achieving a perfect score for the maximum number of bonds possible and establishing a new precedent for bonding in the process. Pörschke announced the team’s discovery in a Division of Inorganic Chemistry symposium at the American Chemical Society national meeting yesterday in San Diego. Going beyond 12 bonds is rare because of the limited space available around the central atom of a molecule and electrostatic repulsion between the ligands. Chemists have flirted with 16-coordinate compounds for years, reporting isolated 15- and 16-coordinate Th-H molecules and a gas-phase 16-coordinate Co-B species. For Pörschke and coworkers, pairing the large singly charged Cs+ cation with the weakly coordinating [H NB (C F ) ]– anion allowed them to go beyond 12 bonds in a complex for the first time without using hydrogen as a ligand. The team prepared Cs[H NB (C F ) ] by using ultrasound to agitate a solution of [Na(OCH CH ) ][H NB (C F ) ] and CsF in dichloromethane. The researchers concentrated the solution and isolated crystals to study by X-ray crystallography. The poor aqueous solubility of the new compound suggested to the researchers that [H NB (C F ) ]– could be a good scavenger of Cs+ in water, which they demonstrated with a set of experiments. Pörschke says that the anion might therefore be useful to pull 134Cs and 137Cs from nuclear waste solutions, as a treatment for 134Cs and 137Cs radiation poisoning, or to prepare implantable 131Cs and 137Cs seeds for radiation therapy. “Pörschke and coworkers have plumbed the limits of coordination chemistry by a careful matching of cation and anion properties,” commented Warren E. Piers, of the University of Calgary, an expert in coordination chemistry. “In addition to the sheer beauty of the molecule, they demonstrate exciting possibilities for radioactive cesium ion sequestration.”

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