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1.
Marcus Heinze Sandra Starke Marcel Händler Hartmut Komber Marco Drache Norbert Moszner Brigitte Voit Doris Pospiech 《应用聚合物科学杂志》2019,136(48):48256
We demonstrate in this study that the combination of modern inline monitoring methods [here: inline nuclear magnetic resonance (NMR)] with simulations gains more exact and profound kinetic results than previously used methods like linearization without that combination. The 1H-NMR spectroscopic data (more than 100 data points) are used to construct the copolymerization diagram. The reactivity ratios are obtained applying the van Herks nonlinear least square method. The examination of the radical copolymerization of 2-hydroxyethyl methacrylate (HEMA) with (2-{[2-(ethoxycarbonyl)prop-2-en-1-yl]oxy}ethyl) phosphonic acid (ECPPA) as important adhesive monomer used in dentistry yields reactivity ratios of rHEMA = 1.83; rECPPA = 0.42. The copolymerization diagram reflects nonideal, non-azeotropic copolymerization. The sequence distribution of the obtained by Monte Carlo simulation indicates the generation of statistical copolymers. As an important finding, it is demonstrated that the repeating units responsible for etching and adhesion are arranged over the whole polymer chain, which is necessary to achieve proper functionality. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48256. 相似文献
2.
Dr. Brigitte Oesterdiekhoff 《Informatik-Spektrum》2004,27(5):448-452
3.
Peter Horn Peter Schaaf Brigitte Holbach Stefan Hölzl Heinz Eschnauer 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1993,196(5):407-409
For provenance assignments of wines strontium isotope ratios can be used because soils from different wine-growing regions, and hence the wines grown there, each show specific ratios. Some successful applications are demonstrated.
87Sr/86Sr aus Gestein und Boden in Rebe und Wein
Zusammenfassung Zur Herkunftsbestimmung von Weinen können Strontium-Isotopenverhältnisse herangezogen werden, da die Böden verschiedener Weinbaugebiete, und damit die dort gezogenen Weine, jeweils spezifische Verhältnisse aufweisen. Einige erfolgreiche Anwendungen werden demonstriert.相似文献
4.
Rainwater collection as a possible water source in developing countries is introduced. The major parameters in calculating the size of the tank are defined. Six methods that have been used previously to relate demand, storage, reliability and the rainfall pattern are compared to the Ottawa Model over a wide range of demands. 相似文献
5.
As-produced nanotubes form a light, fragile and isotropic soot. Different efforts are made to process nanotubes into macroscopic forms of more practical use and more controlled properties. We briefly review in this paper two methods recently proposed to make films of magnetically aligned nanotubes and fibers by using an electrophoretic method. Preferential orientation of the nanotubes in the plane of the films or along the fiber axis is an important feature of the obtained materials. Then we describe in details a different, spinning like, process for making fibers out of single wall carbon nanotubes. This process consists of dispersing the nanotubes in a surfactant solution, re-condensing the nanotubes in the flow of a polymer solution to form a nanotube mesh, and then collating this mesh to a nanotube fiber. The behaviors of the surfactant-stabilized dispersions, which are also presented, are critical for this process. The degree of nanotubes alignment in dried fibers has been characterized by X-ray scattering. It is found to be smaller than the alignment obtained in the previous materials. However, the processing is simpler and faster and potentially scalable for large-scale production. 相似文献
6.
For networks that are directed or can be represented by a directed network,reversing one or more of the uni-directional links may provide the ability to reconnect a network that has been disconnected by link failure.In this paper,a new approach to reconfigure such networks is proposed.We develop a linear time algorithm which,when reachability has been destroyed by the removal of a single link,optimally restores reachability through the reversal of selected links.Multi-link failure reconnectability is discussed and an algorithm with polynomial complexity is given which provides a nearly optimum solution to reconnect the network.We show that the reliability of a network that allows reversals is at least twice more than that in which reversals are not permitted.Unfortunately,the reconnection of some networks cannot be established.Therefore,we discuss the maximization of reachability of such networks so that each node can reach maximum number of the other nodes. 相似文献
7.
Giant Electric Dipole Resonance (GDR) parameters for γ decay to excited states with finite spin and temperature are compiled. Over 100 original works have been reviewed and from some 70 of them, about 350 sets of hot GDR parameters for different isotopes, excitation energies, and spin regions have been extracted. All parameter sets have been brought onto a common footing by calculating the equivalent Lorentzian parameters. The current compilation is complementary to an earlier compilation by Samuel S. Dietrich and Barry L. Berman (At. Data Nucl. Data Tables 38 (1988) 199-338) on ground-state photo-neutron and photo-absorption cross sections and their Lorentzian parameters. A comparison of the two may help shed light on the evolution of GDR parameters with temperature and spin. The present compilation is current as of July 2006. 相似文献
8.
Rogier Schonenborg Adalberto Costessi Peter Schiller 《Microgravity science and technology》2007,19(5-6):219-224
This paper gives a quick overview of how various scientific, operational and safety related requirements drove the development of hardware for the Bone Proteomics (BOP) experiment that was conducted on the International Space Station during the Italian Soyuz Mission in 2005. The experiment objectives will be highlighted briefly and design solutions will be presented. Comments will be given regarding the choice of a particular design solution and the impact on the complexity, cost and development time. Conclusions in this paper are based on the experience gained when developing the BOP experiment hardware and other relatively small experiment hardware packages, typical of European Soyuz Missions. The observations should not be extrapolated to large payloads. The objective of this paper is not to produce a recipe for developing experiment hardware; dedicated documents for that purpose are available elsewhere. Rather, the objective is to help others profit from experience gained in the development of relatively small experiment hardware packages, and to highlight where time and cost saving decisions can be made. 相似文献
9.
The reachability of a strongly connected network may be destroyed after link damage,Since many networds have directed links with the potential for reversal,the reachability may be restored by reversing the direction of links.In this paper,the reliability of a network that allows reversal of links in discussed. 相似文献
10.
Jean-Marie Degroodt Brigitte Wyhowski de Bukanski Sarah Srebrnik 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1992,195(6):566-568
Summary A method combining immunoaffmity-chromatography (IAC) and high-performance liquid chromatography (HPLC) for the analysis of Salbutamol in liver with a low quantification limit of 1 g/kg has been developed. Salbutamol was extracted with 0.01 mol/L HCl and purified by IAC. The samples were analysed on a liquid Chromatograph fitted with a C18 -Bondapak column. A fluorometer was used for the detection of salbutamol. Recoveries of 67–80% could be obtained.
Immunoaffinitätschromatographische Reinigung von Salbutamol in Leber und Rückstandsbestimmung mittels HPLC und fluorimetrischer Detektion
Zusammenfassung Eine Methode, die Immunoaffinitäts-und Hochleistungsflüssigchromatographie verbindet, ist für die Analyse von Salbutamol in Leber entwickelt worden. Eine niedrige Bestimmungsgrenze von 1 g/kg Leber wurde erreicht. Salbutamol wurde mit 0,01 mol/L Salzsäure freigesetzt und durch Immunoaffinitätschromatographie gereinigt. Die Proben wurden durch Flüssigchromatographie auf einer C18 -Bondapak-Säule analysiert. Ein Fluorimeter wurde für die Detektion von Salbutamol benutzt. Ausbeuten von 67 bis 80% konnten erreicht werden.相似文献