Gas transport through ceramic membranes under super-critical conditions

In order to select and to apply a porous membrane under supercritical conditions, it is necessary to understand the transport mechanism affecting the permeation behaviour.This paper describes the investigation of gas transport through micro porous ceramic membranes consisting of several layers. The separation layer is made from TiO² with a nominal pore size diameter of 0.9 nm. Single gas permeation of helium, nitrogen, argon, methane, and carbon dioxide was measured in the temperature range of 293-443 K and in the pressure range of 1-10 MPa.Observation of the permeability of these membranes revealed that the transport of non?adsorbing gases under these conditions is governed by Knudsen diffusion and viscous flow.     

Magnetic Resonance Signal Amplification by Reversible Exchange of Selective PyFALGEA Oligopeptide Ligands Towards Epidermal Growth Factor Receptors

The biorelevant PyFALGEA oligopeptide ligand, which is selective towards the epidermal growth factor receptor (EGFR), has been successfully employed as a substrate in magnetic resonance signal amplification by reversible exchange (SABRE) experiments. It is demonstrated that PyFALGEA and the iridium catalyst IMes form a PyFALGEA:IMes molecular complex. The interaction between PyFALGEA:IMes and H₂ results in a ternary SABRE complex. Selective 1D EXSY experiments reveal that this complex is labile, which is an essential condition for successful hyperpolarization by SABRE. Polarization transfer from parahydrogen to PyFALGEA is observed leading to significant enhancement of the ¹H NMR signals of PyFALGEA. Different iridium catalysts and peptides are inspected to discuss the influence of their molecular structures on the efficiency of hyperpolarization. It is observed that PyFALGEA oligopeptide hyperpolarization is more efficient when an iridium catalyst with a sterically less demanding NHC ligand system such as IMesBn is employed. Experiments with shorter analogues of PyFALGEA, that is, PyLGEA and PyEA, show that the bulky phenylalanine from the PyFALGEA oligopeptide causes steric hindrance in the SABRE complex, which hampers hyperpolarization with IMes. Finally, a single-scan ¹H NMR SABRE experiment of PyFALGEA with IMesBn revealed a unique pattern of NMR lines in the hydride region, which can be treated as a fingerprint of this important oligopeptide.     

High-Pressure Reverse Osmosis for Industrial Water Recycling: Permeate-Sided Pressure Drop as Performance-Limiting Factor

In the chemical industry large amounts of saline wastewater occur. Its disposal into rivers is a considerable burden to the ecosystem. To strive for a circular economy and enable a viable raw material recycling, energy-efficient concentration processes are requisite. High-pressure reverse osmosis meets this criterion, but its industrial application demands suitable membrane elements that withstand the exceptional operation conditions and provide sufficient performance. Hence, new requirements regarding the design of spiral-wound elements arise. To identify those, specific performance-limiting effects need a better understanding.     

Chemical Recycling of Carbon Fiber Reinforced Epoxy Composites Using Mild Conditions

The increased use of carbon fiber reinforced thermosets generates more waste and end-of-life products. However, an efficient recycling method for the expensive carbon fibers has not yet been developed. The selective decomposition of amine-cured epoxy resin under mild conditions is presented. A two-step method was investigated to decompose the epoxy resin. The optimum parameters were initially determined using a model compound. By analysis of the reaction products, a cleavage of the C–N bond according to the Cope elimination could be proven. Therefore, the Cope elimination is suggested as the main step of the decomposition of amine-cured epoxy resins in presence of hydrogen peroxide. By dissolving the resin, it is possible to recover resin-free fibers with unimpaired mechanical properties.     

Using icon arrays to communicate medical risks: Overcoming low numeracy.

Objective: Icon arrays have been suggested as a potentially promising format for communicating risks to patients—especially those with low numeracy skills—but experimental studies are lacking. This study investigates whether icon arrays increase accuracy of understanding medical risks, and whether they affect perceived seriousness of risks and helpfulness of treatments. Design: Two experiments were conducted on samples of older adults (n = 59, 62 to 77 years of age) and university students (n = 112, 26 to 35 years of age). Main Outcome Measures: Accuracy of understanding risk reduction; perceived seriousness of risks; perceived helpfulness of treatments. Results: Icon arrays increased accuracy of both low- and high-numeracy people, even when transparent numerical representations were used. Risks presented via icon arrays were perceived as less serious than those presented numerically. With larger icon arrays (1,000 instead of 100 icons) risks were perceived more serious, and risk reduction larger. Conclusions: Icon arrays are a promising way of communicating medical risks to a wide range of patient groups, including older adults with lower numeracy skills. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modeling laboratory data from clinical trials

Abnormal laboratory data from clinical trials are considered precursors of potential organ dysfunction. Routine analysis of these data focusses primarily on the incidence of extremely high or low values relative to normal ranges, or the change of these incidences compared to baseline. Alternatively, the worst values from each individual patient are analyzed. Where feasible, graphical representations of the time course of lab measurements are displayed, often for each subject individually. However, only rarely is an attempt made to model the dynamics of the measurements over time. Stochastic processes can be used to model laboratory measurements and specifically Ornstein-Uhlenbeck processes have some properties that are suitable for this purpose. Models based on these processes can account for potential systematic effects relevant for all or a group of subjects as well as the random variation between subjects. The idea is to estimate parameters of these processes in order to quantify effects of drugs or other medical treatments. Results based on simulations and real data will be presented.     

Monitoring kidney and renal cyst volumes applying MR approaches on a rapamycin treated mouse model of ADPKD

Object  The aim of our study was to determine total cystic volume in a mouse model of PKD using MR imaging to monitor therapeutic effects in vivo. Materials and methods  We imaged eight female pcy-mice in two groups: four belonged to an untreated control group and four were treated with the anticystic agent rapamycin, which has proven to be effective in reducing cystogenesis in animal models. The mice were imaged using a 9.4 Tesla animal scanner. MRI measurements were taken at six time points during the therapy. Total renal volumes and total cyst volumes were calculated using a thresholding approach. Results  During the course of the treatment, the total cyst volume increased significantly faster than the total renal volume in the untreated group, indicating that growth of the total renal volume in the untreated group was primarily due to the growth of the cysts, rather than the parenchyma. The measured total renal volume in the control (placebo) group was significantly higher than the volume in the treated group. Conclusion  Using MRI, we were able to monitor the cystic volume in a mouse model of PKD to assess the therapeutic effect of anticystic treatment.     

Die Rolle des Experiments in der Verfahrensentwicklung

Experiments in process development . Design data for the improvement of existing plants or for the development of new chemical processes are determined by experiments in laboratories or pilot plants. These frequently expensive testruns should lower the scaling-up risk for industrial plant and should ensure its long-term functioning and its economy. The various methods of scaling-up and the influence of errors are discussed. Some examples will show how an exact planning of the experiments can minimize the costs of development and product.     

ANTARES: The HTR/VHTR project at Framatome ANP

Framatome ANP is developing a very high temperature reactor (VHTR), relying on its previous experience with high temperature reactor concepts, from its participation in the MODUL and the GT-MHR designs. While being a major actor in the nuclear reactor business with proven light water technology, AREVA wishes to be ready to meet the new challenges calling for small grid requirements, high temperature process heat and cogeneration. The Framatome ANP VHTR design for electricity production is based on an indirect cycle coupled to an “off-the-shelf” combined cycle gas turbine. Although direct cycle HTRs are being promoted for their high efficiency, preliminary evaluations show that the Framatome ANP design efficiency is on par with a direct cycle while avoiding power generation system (PGS) developments and keeping the PGS contamination free. Moreover, the nuclear heat source of the indirect cycle could also be used to meet the heat supplies from a standard design for multiple applications.     

Zweiphasige Strömungsvorgänge in Kreiselpumpen unter Berücksichtigung der Energieübertragung im Laufrad und in der Leiteinrichtung

Zusammenfassung In den verschiedenen Str?mungsbereichen der Kreiselpumpe stellt sich zwischen Feststoffpartikeln und Tr?gerfluid (z. B. Wasser) infolge des Dichteunterschiedes eine Phasenrelativgeschwindigkeit ein. Hieraus resultiert ein differenziertes Verhalten der Phasen bei der Energieübertragung. Auf der Grundlage von [1] sollen die Bewegungsvorg?nge n?her untersucht werden, wobei aus dem Kr?ftegleichgewicht auf die Phasengeschwindigkeiten und damit die Bahnbewegung geschlossen werden kann.