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Production of Y-86 and other radiometals for research purposes using a solution target system
(2015)
Experimental determination of the cross sections of proton capture on radioactive nuclei is extremely difficult. Therefore, it is of substantial interest for the understanding of the production of the p-nuclei. For the first time, a direct measurement of proton-capture cross sections on stored, radioactive ions became possible in an energy range of interest for nuclear astrophysics. The experiment was performed at the Experimental Storage Ring (ESR) at GSI by making use of a sensitive method to measure (p,γ) and (p,n) reactions in inverse kinematics. These reaction channels are of high relevance for the nucleosyn-thesis processes in supernovae, which are among the most violent explosions in the universe and are not yet well understood. The cross section of the ¹¹⁸Te(p,γ) reaction has been measured at energies of 6 MeV/u and 7 MeV/u. The heavy ions interacted with a hydrogen gas jet target. The radiative recombination process of the fully stripped ¹¹⁸Te ions and electrons from the hydrogen target was used as a luminosity monitor. An overview of the experimental method and preliminary results from the ongoing analysis will be presented.
Ein viel versprechender erneuerbarer Rohstoff für die Produktion von Chemikalien und Treibstoffen ist Lignocellulose aus pflanzlicher Biomasse. Die darin enthaltenen Zucker können mittels enzymatischer Hydrolyse freigesetzt und fermentativ zu Ethanol umgesetzt werden. Ein interessanter Ansatz ist dabei die simultane Verzuckerung und Fermentation. Hefen und Enzyme haben mit 30 °C bzw. 50 °C zwar unterschiedliche Temperaturoptima, es konnte aber gezeigt werden, dass auch bei den niedrigeren Temperaturen eine Umsetzung der Cellulose zu Glucose erfolgt, wenn auch langsamer als bei optimalen Bedingungen. Außerdem konnte in Vorversuchen gezeigt werden, dass Ethanol in den zu erwartenden Konzentrationen keinen Einfluss auf die enzymatische Umsetzung hat.
In traditional microbial biobutanol production, the solvent must be recovered during fermentation process for a sufficient space-time yield. Thermal separation is not feasible due to the boiling point of n-butanol. As an integrated and selective solid-liquid separation alternative, solvent impregnated resins (SIRs) were applied. Two polymeric resins were evaluated and an extractant screening was conducted. Vacuum application with vapor collection in fixed-bed column as bioreactor bypass was successfully implemented as butanol desorption step. In course of further increasing process economics, fermentation with renewable lignocellulosic substrates was conducted using Clostridium acetobutylicum. Utilization of SIR was shown to be a potential strategy for solvent removal from fermentation broth, while application of a bypass column allows for product removal and recovery at once.
Heparin is a natural polysaccharide, which plays essential role in many biological processes. Alterations in building blocks can modify biological roles of commercial heparin products, due to significant changes in the conformation of the polymer chain. The variability structure of heparin leads to difficulty in quality control using different analytical methods, including infrared (IR) spectroscopy. In this paper molecular modelling of heparin disaccharide subunits was performed using quantum chemistry. The structural and spectral parameters of these disaccharides have been calculated using RHF/6-311G. In addition, over-sulphated chondroitin sulphate disaccharide was studied as one of the most widespread contaminants of heparin. Calculated IR spectra were analyzed with respect to specific structure parameters. IR spectroscopic fingerprint was found to be sensitive to substitution pattern of disaccharide subunits. Vibrational assignments of calculated spectra were correlated with experimental IR spectral bands of native heparin. Chemometrics was used to perform multivariate analysis of simulated spectral data.
Quaternary events at the Horn of Africa / Voigt, B., B. Gabriel, B. Lassonczyk and Mumin M. Ghod
(1990)
Oxorhenium(V) complexes [ReOX3(PPh3)2] (X = Cl, Br) react with phenylacetylene under formation of complexes with ylide-type ligands. Compounds of the compositions [ReOCl3(PPh3){C(Ph)C(H)(PPh3)}] (1), [ReOBr3(OPPh3){C(Ph)C(H)(PPh3)}] (2), and [ReOBr3(OPPh3){C(H)C(Ph)(PPh3)}] (3) were isolated and characterized by X-ray diffraction. They contain a ligand, which was formed by a nucleophilic attack of released PPh3 at coordinated phenylacetylene. The structures of the products show that there is no preferable position for this attack. Cleavage of the Re–C bond in 3 and dimerization of the organic ligand resulted in the formation of the [{(PPh3)(H)CC(Ph)}2]2+ cation, which crystallized as its [(ReOBr4)(OReO3)]2– salt.
A major part of edible oil is subjected to bleaching procedures, primarily with minerals applied as adsorbers. Their recycling is currently done either by regaining the oil via organic solvent extraction or by using the spent bleaching earth (SBE) as additive for animal feed, etc. As a new method, the reutilization of the by-product SBE for the microbiologic formation of acetone, butanol, and ethanol (ABE) is presented as proof-of-concept. The SBE was taken from a palm oil cleaning process. The recycling concept is based on the application of lipolytic clostridia strains. Due to considerably long fermentation times, co-fermentation with Candida rugosa and enzymatic hydrolyses of the bound oil with a subsequent clostridia fermentation are shown as alternative routes. Anaerobic fermentations under comparison of different clostridia strains were performed with glycerol media, enzymatically hydrolyzed palm oil and SBE. Solutes, side product compositions and productivities were quantified via HPLC. A successful production of ABE solutes from SBE has been done with a yield of 0.15 g butanol per gram of bound glycerol. Thus, the biotechnological recycling of the waste stream is possible in principle. Inhibition of the substrate suspension has been observed. A chromatographic ion-exchange of substrates increased the biomass concentration.
Die Erfindung betrifft eine schwefelvernetzbare Kautschukmischung, deren Vulkanisat und einen Fahrzeugreifen. Die erfindungsgemäße Kautschukmischung enthält wenigstens folgende Bestandteile: - Wenigstens einen Dienkautschuk; - wenigstens eine Kohle (HTC-Kohle), die mittels hydrothermaler Karbonisierung von wenigstens einer Ausgangssubstanz hergestellt ist. Der erfindungsgemäße Fahrzeugreifen weist in wenigstens einem Bauteil wenigstens ein erfindungsgemäßes Vulkanisat der Kautschukmischung auf.
Die Erfindung betrifft eine schwefelvernetzbare Kautschukmischung, deren Vulkanisat und einen Fahrzeugreifen. Die schwefelvernetzbare Kautschukmischung enthält wenigstens die folgenden Bestandteile: - wenigstens einen Dienkautschuk; und - 10 bis 300 phr wenigstens einer Kieselsäure; und - 1 bis 30 phf wenigstens eines Silans A mit der allgemeinen Summenformel A-I) A-I)(R1)oSi-R2-(S-R3)q-S-X; und - 0,5 bis 30 phf wenigstens eines Silans B mit der allgemeinen Summenformel B-I) B-I) (R1)oSi-R2-(S-R3)u-S-R2-Si(R1)o wobei q =1, 2 oder 3 ist; und u = 1, 2 oder 3 ist; und X ein Wasserstoffatom oder eine –C(=O)-R8 Gruppe ist wobei R8 ausgewählt ist aus Wasserstoff, C1-C20 Alkylgruppen, vorzugsweise C1-C17, C6-C20- Arylgruppen, vorzugsweise Phenyl, C2-C20-Alkenylgruppen und C7-C20-Aralkylgruppen.
Die Erfindung betrifft eine schwefelvernetzbare Kautschukmischung, deren Vulkanisat und einen Fahrzeugreifen.Die schwefelvernetzbare Kautschukmischung enthält wenigstens die folgenden Bestandteile:- wenigstens einen Dienkautschuk; und- 10 bis 300 phr wenigstens einer Kieselsäure ; und- 1 bis 30 phf wenigstens eines Silans A mit der allgemeinen Summenformel A-I)und- 0,5 bis 30 phf wenigstens eines Silans B mit der allgemeinen Summenformel B-I)wobei u gleich 0, 1, 2 oder 3 und v gleich 0 oder 1 ist.
Sekundäre galvanische Zelle
(2020)
Die vorliegende Erfindung betrifft eine sekundäre galvanische Zelle, umfassend eine Kathode, eine Anode und einen Separator, der zwischen der Kathode und der Anode angeordnet ist, wobei die Kathode ein erstes elastomeres Polymer umfasst, welches mit einem ersten Füllstoff als Kathodenmaterial gefüllt ist, wobei die Anode ein zweites elastomeres Polymer umfasst, welches mit einem zweiten Füllstoff als Anodenmaterial gefüllt ist, wobei der Separator ein drittes elastomeres Polymer umfasst, wobei das erste elastomere Polymer, das zweite elastomere Polymer und das dritte elastomere Polymer unabhängig voneinander aus vernetzungsfähigen Dienkautschuken ausgewählt sind, und wobei zumindest eines von dem ersten elastomeren Polymer, dem zweiten elastomeren Polymer und dem dritten elastomeren Polymer eine ionische Flüssigkeit und/oder ein elektrisch leitfähiges Polymer enthält. Die vorliegende Erfindung betrifft ferner eine wiederaufladbare Batterie, umfassend die erfindungsgemäße sekundäre galvanische Zelle, ein Verfahren zur Herstellung einer sekundären galvanischen Zelle sowie die Verwendung der erfindungsgemäßen sekundären galvanischen Zelle sowie der erfindungsgemäßen wiederaufladbaren Batterie.
In Anbetracht des zu erwartenden Rückgangs der Verfügbarkeit fossiler Rohstoffe müssen nicht nur für den Energiesektor, sondern auch für die Herstellung industrieller Produkte alternative Rohstoffe gefunden werden. Ein Beispiel für einen nicht in Nahrungsmittelkonkurrenz stehenden nachwachsenden Rohstoff ist grüne Biomasse wie Gras und Klee. Diese lassen sich in Deutschland auf großen Flächen anbauen und enthalten eine Vielzahl potenzieller Substrate für Fermentationen.
In this study, a recently proposed NMR standardization approach by 2H integral of deuterated solvent for quantitative multicomponent analysis of complex mixtures is presented. As a proof of principle, the existing NMR routine for the analysis of Aloe vera products was modified. Instead of using absolute integrals of targeted compounds and internal standard (nicotinamide) from 1H-NMR spectra, quantification was performed based on the ratio of a particular 1H-NMR compound integral and 2H-NMR signal of deuterated solvent D2O. Validation characteristics (linearity, repeatability, accuracy) were evaluated and the results showed that the method has the same precision as internal standardization in case of multicomponent screening. Moreover, a dehydration process by freeze drying is not necessary for the new routine. Now, our NMR profiling of A. vera products needs only limited sample preparation and data processing. The new standardization methodology provides an appealing alternative for multicomponent NMR screening. In general, this novel approach, using standardization by 2H integral, benefits from reduced sample preparation steps and uncertainties, and is recommended in different application areas (purity determination, forensics, pharmaceutical analysis, etc.).
We present an electromechanically coupled Finite Element model for cardiac tissue. It bases on the mechanical model for cardiac tissue of Hunter et al. that we couple to the McAllister-Noble-Tsien electrophysiological model of purkinje fibre cells. The corresponding system of ordinary differential equations is implemented on the level of the constitutive equations in a geometrically and physically nonlinear version of the so-called edge-based smoothed FEM for plates. Mechanical material parameters are determined from our own pressure-deflection experimental setup. The main purpose of the model is to further examine the experimental results not only on mechanical but also on electrophysiological level down to ion channel gates. Moreover, we present first drug treatment simulations and validate the model with respect to the experiments.
Mit freundlicher Genehmigung der Autoren und des Oldenbourg Industrieverlags https://www.oldenbourg-industrieverlag.de/de/9783835633223-33223 erschienen als Beitrag im Tagungsband zur AALE-Tagung 2012. 9. Fachkonferenz 4.-5. Mai 2012, Aachen, Fachhochschule. ISBN 9783835633223 S 5-1 S. 127-135 Es werden Ergebnisse unterschiedlicher Projekte aus dem Bereich der Simulation von Wärmeübertragungsprozessen mit Excel-VBA vorgestellt. - Thermische Behandlung hochviskoser Fruchtzubereitungen, verschiedene Projekte und Kooperationen mit der Zentis GmbH & Co. KG, Aachen (J. Becker, U. Feuerriegel, G. Wersch). - Untersuchung des dynamischen Verhaltens von dampfbeheizten Ethylen-Verdampfern. Projekt mit der TGE Gas Engineering GmbH, Bonn (M. Ecker, U. Feuerriegel, U. Hoffmann, S. Wittenhorst). - Dynamische Simulation des axialen Temperaturverlaufs von elektrisch beheizten Rohrreaktoren. Kooperation mit dem Institut für Chemische Verfahrenstechnik, TU Clausthal (U. Feuerriegel, U. Kunz, M. Pook, S. Wittenhorst).
Simultane Atline-Quantifizierung von Magnetpartikeln und Mikroorganismen bei einer HGMS-Filtration
(2015)
Es wird eine neue Atline-Messmethode vorgestellt, mit der während einer Hochgradienten-Magnetseparation (HGMS)-Filtration eine simultane Quantifizierung von Magnetpartikeln und Mikroorganismen im Filtrat vorgenommen werden kann. Dabei gelingt die Quantifizierung signifikant besser als mit bisher verwendeten Messmethoden. Mit dieser Methode ist es möglich, die Trennleistung einer HGMS-Filtration zu bestimmen und einen Filterdurchbruch durch Konzentrationsanstiege im Bereich einiger µg L−1 von Magnetpartikeln im Filtrat frühzeitig zu detektieren, ohne dass nennenswerte Partikelmengen verloren gehen.
Size unlimited markerless deletions by a transconjugative plasmid-system in Bacillus licheniformis
(2013)
Slot die coating is applied to deposit thin and homogenous films in roll-to-roll and sheet-to-sheet applications. The critical step in operation is to choose suitable process parameters within the process window. In this work, we investigate an upper limit for stripe coatings. This maximum film thickness is characterized by stripe merging which needs to be avoided in a stable process. It is shown that the upper limit reduces the process window for stripe coatings to a major extent. As a result, stripe coatings at large coating gaps and low viscosities are only possible for relatively thick films. Explaining the upper limit, a theory of balancing the side pressure in the gap region in the cross-web direction has been developed.
The Gram-positive endospore-forming bacterium Bacillus licheniformis can be found widely in nature and it is exploited in industrial processes for the manufacturing of antibiotics, specialty chemicals, and enzymes. Both in its varied natural habitats and in industrial settings, B. licheniformis cells will be exposed to increases in the external osmolarity, conditions that trigger water efflux, impair turgor, cause the cessation of growth, and negatively affect the productivity of cell factories in biotechnological processes. We have taken here both systems-wide and targeted physiological approaches to unravel the core of the osmostress responses of B. licheniformis. Cells were suddenly subjected to an osmotic upshift of considerable magnitude (with 1 M NaCl), and their transcriptional profile was then recorded in a time-resolved fashion on a genome-wide scale. A bioinformatics cluster analysis was used to group the osmotically up-regulated genes into categories that are functionally associated with the synthesis and import of osmostress-relieving compounds (compatible solutes), the SigB-controlled general stress response, and genes whose functional annotation suggests that salt stress triggers secondary oxidative stress responses in B. licheniformis. The data set focusing on the transcriptional profile of B. licheniformis was enriched by proteomics aimed at identifying those proteins that were accumulated by the cells through increased biosynthesis in response to osmotic stress. Furthermore, these global approaches were augmented by a set of experiments that addressed the synthesis of the compatible solutes proline and glycine betaine and assessed the growth-enhancing effects of various osmoprotectants. Combined, our data provide a blueprint of the cellular adjustment processes of B. licheniformis to both sudden and sustained osmotic stress.
Nacre-mimetic nanocomposites based on high fractions of synthetic high-aspect-ratio nanoclays in combination with polymers are continuously pushing boundaries for advanced material properties, such as high barrier against oxygen, extraordinary mechanical behavior, fire shielding, and glass-like transparency. Additionally, they provide interesting model systems to study polymers under nanoconfinement due to the well-defined layered nanocomposite arrangement. Although the general behavior in terms of forming such layered nanocomposite materials using evaporative self-assembly and controlling the nanoclay gallery spacing by the nanoclay/polymer ratio is understood, some combinations of polymer matrices and nanoclay reinforcement do not comply with the established models. Here, we demonstrate a thorough characterization and analysis of such an unusual polymer/nanoclay pair that falls outside of the general behavior. Poly(ethylene oxide) (PEO) and sodium fluorohectorite form nacre-mimetic, lamellar nanocomposites that are completely transparent and show high mechanical stiffness and high gas barrier, but there is only limited expansion of the nanoclay gallery spacing when adding increasing amounts of polymer. This behavior is maintained for molecular weights of PEO varied over four orders of magnitude and can be traced back to depletion forces. By careful investigation via X-ray diffraction and proton low-resolution solid-state NMR, we are able to quantify the amount of mobile and immobilized polymer species in between the nanoclay galleries and around proposed tactoid stacks embedded in a PEO matrix. We further elucidate the unusual confined polymer dynamics, indicating a relevant role of specific surface interactions.