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61.
Maike Gleichenhagen Benno F. Zimmermann Birgit Herzig Ingar Janzik Siegfried Jahnke Markus Boner Peter Stehle Rudolf Galensa 《Food chemistry》2013
The intrinsic isotopic labelling of plants with 13CO2 is an effective method to generate highly labelled compounds using photosynthesis and avoiding labour-intensive complex organic syntheses. In this study, the intrinsic isotopic labelling of polyphenols in parsley, spinach and peppermint is shown for the first time. The plants were grown in an atmosphere where 12CO2 was replaced by 13CO2, in order to generate highly labelled compounds. The total content of 13C as well as the individual polyphenols were analysed by Isotopic Ratio-MS and HPLC–Iontrap-MSn. 相似文献
62.
Thomas Beer Tobias Meisen Rudolf Reinhard Sergey Konovalov Daniel Schilberg Sabina Jeschke Torsten Kuhlen Christian Bischof 《Production Engineering》2011,5(4):383-391
Computational simulations are used for the optimization of production processes in order to significantly reduce the need
for costly experimental optimization approaches. Yet individual simulations can rarely describe more than a single production
step. A set of simulations has to be coupled to each other to form a contiguous representation of a process chain. Eventually,
simulated results have to be analyzed by domain experts to gather insight from the preformed computations. In this paper,
we propose an IT infrastructure and software tools that aim at a rather non-intrusive way of coupling resources and domain
expert’s knowledge to enable the collaborative setup, execution and analysis of distributed simulation chains. We illustrate
the approach in the domain of materials processing. Beyond means originating from the domain of GRID computing for resource
management, a data integration component assures semantic data integrity between the simulation steps and stores simulation
data in an application independent way. Thus, we can transform this data into native formats for each simulation tool, and
finally into a format that allows for contiguous visualizations and an intuitive, comprehensive analysis of complete simulated
process chains. 相似文献
63.
Thomas Anung Basuki Antonio Cerone Andreas Griesmayer Rudolf Schlatte 《Formal Aspects of Computing》2009,21(6):571-588
This article describes a framework to formally model and analyse human behaviour. This is shown by a simple case study of
a chocolate vending machine, which represents many aspects of human behaviour. The case study is modelled and analysed using
the Maude rewrite system. This work extends a previous work by Basuki which attempts to model interactions between human and
machine and analyse the possibility of errors occurring in the interactions. By redesigning the interface, it can be shown
that certain kinds of error can be avoided for some users. This article overcomes the limitation of Basuki’s approach by incorporating
many aspects of user behaviour into a single user model, and introduces a more natural approach to model human–computer interaction. 相似文献
64.
Prabhas Kumar Yadav Falk Händel Christian Müller Rudolf Liedl Peter Dietrich 《Grundwasser》2013,18(1):47-53
Groundwater pollution with organic contaminants remains a world-wide problem. Before selection of any remediation technique, it is important to pre-assess contaminated sites with respect to their hazard. For this, several analytical and numerical approaches have been used and an initial assessment of contaminated sites the MS-Excel© tool “NAFLA” was developed. “NAFLA” allows a quick and straightforward calculation and comparison of some analytical approaches for the estimation of maximum plume length under steady-state conditions. These approaches differ from each other in source geometry, model domain orientation, and in the consideration of (bio)chemical reaction within the domain. In this communication, we provide details about the development of “NAFLA”, its possible usage and information for users. The tool is especially designed for application in student education, by authorities and consultants. 相似文献
65.
Rudolf Herzog 《?sterreichische Wasser- und Abfallwirtschaft》2009,61(11-12):a30-a33
66.
Lütke-Eversloh T Fischer A Remminghorst U Kawada J Marchessault RH Bögershausen A Kalwei M Eckert H Reichelt R Liu SJ Steinbüchel A 《Nature materials》2002,1(4):236-240
The development of non-petrochemical sources for the plastics industry continues to progress as large multinationals focus on renewable resources to replace fossil carbon. Many bacteria are known to accumulate polyoxoesters as water-insoluble granules in the cytoplasm. The thermoplastic and/or elastomeric behaviour of these biodegradable polymers holds promise for the development of various technological applications. Here, we report the synthesis and characterization of microbial polythioesters (PTEs), a novel class of biopolymers of general technological relevance. Biosynthesis of PTE homopolymers was achieved using a recombinant strain of Escherichia coli that expressed a non-natural pathway consisting of a butyrate kinase, a phosphotransbutyrylase, and a PHA synthase. Different homopolymers were produced, consisting of either 3-mercaptopropionate, 3-mercaptobutyrate, or 3-mercaptovalerate repeating units, if the respective mercaptoalkanoic acids were provided as precursor substrates to the fermentative process. The PTEs contributed up to 30% (w/w) of the cellular dry weight and were identified as hydrophobic inclusions in the cytoplasm. The chemical and stereochemical homogeneity of the purified PTEs were identified by different methods, and the estimated physical properties were compared to the oxypolyester equivalents, revealing low crystalline order and, for the poly(3-mercaptopropionate) improved thermal stability. The ability to produce PTEs through a biosynthetic route opens up new avenues in the field of biomaterials. 相似文献
67.
A simplified sample pretreatment method for industrially PAH-contaminated soils applying automated Soxhlet (Soxtherm) with ethyl acetate as extraction solvent is presented. Laborious pretreatment steps such as drying of samples, cleanup of crude extracts, and solvent exchange were allowed to be bypassed without notable performance impact. Moisture of the soil samples did not significantly influence recoveries of PAHs at a wide range of water content for the newly developed method. However, the opposite was true for the standard procedure using the more apolar 1:1 (v/v) n-hexane/acetone solvent mixture including postextraction treatments recommended by the U.S. EPA. Moreover, ethyl acetate crude extracts did not appreciably effect the chromatographic performance (HPLC-(3D)FLD), which was confirmed by a comparison of the purity of PAH spectra from both pretreatment methods. Up to 20% (v/v) in acetonitrile, ethyl acetate proved to be fully compatible with the mobile phase of the HPLC whereas the same concentration of n-hexane/acetone in acetonitrile resulted in significant retention time shifts. The newly developed pretreatment method was applied to three historically contaminated soils from different sources with extraction efficiencies not being significantly different compared to the standard procedure. Finally, the certified reference soil CRM 524 was subjected to the simplified procedure resulting in quantitative recoveries (>92%) for all PAHs analyzed. 相似文献
68.
Blom H Johansson M Gösch M Sigmundsson T Holm J Hård S Rigler R 《Applied optics》2002,41(31):6614-6620
We have developed a multifocal optical fluorescence correlation spectroscopy system for parallel flow analyses. Multifocal excitation was made possible through a 4 x 1 diffractive optical fan-out element, which produces uniform intensity in all four foci. Autocorrelation flow analyses inside a 20 microm x 20 microm square microchannel, with the 4 x 1 fan-out foci perpendicular to the flow direction, made it possible to monitor different flows in all four foci simultaneously. We were able to perform cross-correlation flow analyses by turning the microstructure, thereby having all four foci parallel to the direction of flow. Transport effects of the diffusion as a function of flow and distance could then also be studied. 相似文献
69.
The transportable setup of the Cologne Tuneable Heterodyne Infrared Spectrometer (THIS) is presented. Frequency tuneability over a wide range provided by the use of tuneable diode lasers as local oscillators (LO) allows a variety of molecules in the mid-infrared to be observed. Longtime integration, which is essential for astronomical observations, is possible owing to tight frequency control of the LO with optical feedback from an external cavity. THIS is developed to fly on the Stratospheric Observatory for Infrared Astronomy beginning in 2006 but can also be used on different types of ground-based telescopes. 相似文献
70.
Brennan Penny L.; Schutte Kathleen K.; Moos Rudolf H. 《Canadian Metallurgical Quarterly》2006,13(3):253
At 1 year, 4 years, and 10 years after baseline, late-middle-aged adults reported whether they had successfully resolved their most important stressor of the past year. Compared to individuals who never resolved focal stressors over the 10-year interval, those who always did consistently showed less negative stressor appraisal, less reliance on avoidance coping, and less use of exploratory relative to directed coping responses, independent of type and severity of focal stressor. Less use of exploratory relative to directed coping and having more social resources, fewer health problems, and fewer depressive symptoms at baseline predicted more stressor resolution over the next 10 years. These predictors are promising foci for prospective efforts to optimize ways in which aging adults manage late-life stressors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献