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41.
J.R. Maiorino C.E. Siewert 《Journal of Quantitative Spectroscopy & Radiative Transfer》1980,24(2):159-165
The FN method is used to establish numerical results basic to polarization studies in plane parallel atmospheres. 相似文献
42.
G.C. Pomraning C.E. Siewert 《Journal of Quantitative Spectroscopy & Radiative Transfer》1982,28(6):503-506
Basic considerations are used to derive the integral form of the equation of transfer relevant to a homogeneous sphere with internal sources as well as external illumination and a specularly and diffusely reflecting surface. 相似文献
43.
Wendy R. Altman John Moreland Victor M. Bright 《Journal of magnetism and magnetic materials》2010,322(21):3236-3239
Magneto-optic Kerr effect (MOKE) and magnetoresistance (MR) measurements were used to measure the switching characteristics of spin-valve (SV) arrays currently being developed to trap and release superparamagnetic beads within a fluid medium. The effect of SV size on switching observed by MOKE showed that a 1 μm×8 μm SV element was found to have optimal switching characteristics. MR measurements on a single 1 μm×8 μm SV switched with either an external applied magnetic field or a local magnetic field generated by an integrated write wire (current density ranging from 106 to 107 A/cm2) confirmed the MOKE findings. The 1 μm×8 μm SV low field switching was observed to be +8 and −2 mT with two stable states at zero field; the high field switching was observed to be −18 mT. The low switching fields and the large magnetic moment of the SV trap along with our observation of minimal magnetostatic effects for dense arrays are necessary design characteristics for high-force, “switchable-magnet,” microfluidic bead trap applications. 相似文献
44.
H. Siewert G. Schneider D. Strańgfeld K. Buchali 《Isotopes in environmental and health studies》2013,49(8):330-334
Der vom VEB Vakutronik WIB Dresden hergestellete Szintiscanner “Szintitites” wird auf seine Einsatzmöglichlichkeit für die Nierenszintigraphic geprüft. Dazu werden Szintigramme von Modellen aufgenommen, die in ihren Impulsdichten in der Gröβenordnung liegen, wie sie nach Applikation von 300 500µCi131 J-Hippuran über den Nieren und dem anderen Gewebe der Patienten gefunden werden. Zum Einsatz kommt dabei der Konuskollimator mit einer Apertur von 12 mm. Die besser auflösenden 9- und 19- Kanal-Kollimatoren scheiden für die Nierenszintigraphie mit dem “Szintitest” aus, da ihre Effektivität zu gering ist. Die Einflüsse der Abtastgeschwindigkeit, einer bestimmten Untergrundzählrate und eines variablen Abstandes zwischen Scanner und Objekt werden untersucht. Dabei zeigt sich, daβ ein Körperoberfläche, nicht erreicht werden kann. Das Auflösungsvermögen als 2 cm auch im günstigsten Fall von etwa 8 cm Abstand von der Nierenoberfläche, d. h. 2 4 cm von der Köperoberfläche, nicht werden kann. Das Auflösungsvermögen verschlechtert sich dagegen noch je nach Abstand und Untergrun von 2 auf 3 cm. 相似文献
45.
Peter?EntelEmail author Mario?Siewert Markus?E.?Gruner Heike?C.?Herper Denis?Comtesse Raymundo?Arróyave Navedeep?Singh Anjana?Talapatra Vladimir?V.?Sokolovskiy Vasiliy?D.?Buchelnikov Franca?Albertini Lara?Righi Volodymyr?A.?Chernenko 《The European Physical Journal B - Condensed Matter and Complex Systems》2013,86(2):65
First-principles calculations are used to study the structural, electronic and magnetic properties of (Pd, Pt)-Mn-Ni-(Ga, In, Sn, Sb) alloys, which display multifunctional properties like the magnetic shape-memory, magnetocaloric and exchange bias effect. The ab initio calculations give a basic understanding of the underlying physics which is associated with the complex magnetic behavior arising from competing ferro- and antiferromagnetic interactions with increasing number of Mn excess atoms in the unit cell. This information allows to optimize, for example, the magnetocaloric effect by using the strong influence of compositional changes on the magnetic interactions. Thermodynamic properties can be calculated by using the ab initio magnetic exchange parameters in finite-temperature Monte Carlo simulations. We present guidelines of how to improve the functional properties. For Pt-Ni-Mn-Ga alloys, a shape memory effect with 14% strain can be achieved in an external magnetic field. 相似文献
46.
Jia-Pei Du Dr. Alexander Wilting Prof. Dr. Inke Siewert 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(21):5555-5564
Here, the reduction chemistry of mono- and binuclear α-diimine-Re(CO)3 complexes with proton responsive ligands and their application in the electrochemically-driven CO2 reduction catalysis are presented. The work was aimed to investigate the impact of 1) two metal ions in close proximity and 2) an internal proton source on catalysis. Therefore, three different Re complexes, a binuclear one with a central phenol unit, 3 , and two mononuclear, one having a central phenol unit, 1 , and one with a methoxy unit, 2 , were utilised. All complexes are active in the CO2-to-CO conversion and CO is always the major product. The catalytic rate constant kcat for all three complexes is much higher and the overpotential is lower in DMF/water mixtures than in pure DMF (DMF=N,N-dimethylformamide). Cyclic voltammetry (CV) studies in the absence of substrate revealed that this is due to an accelerated chloride ion loss after initial reduction in DMF/water mixtures in comparison to pure DMF. Chloride ion loss is necessary for subsequent CO2 binding and this step is around ten times faster in the presence of water [ 2 : kCl(DMF)≈1.7 s−1; kCl(DMF/H2O)≈20 s−1]. The binuclear complex 3 with a proton responsive phenol unit is more active than the mononuclear complexes. In the presence of water, the observed rate constant kobs for 3 is four times higher than of 2 , in the absence of water even ten times. Thus, the two metal centres are beneficial for catalysis. Lastly, the investigation showed that the phenol unit has no impact on the rate of the catalysis, it even slows down the CO2-to-CO conversion. This is due to an unproductive, competitive side reaction: After initial reduction, 1 and 3 loose either Cl− or undergo a reductive OH deprotonation forming a phenolate unit. The phenolate could bind to the metal centre blocking the sixth coordination site for CO2 activation. In DMF, O−H bond breaking and Cl− ion loss have similar rate constants [ 1 : kCl(DMF)≈2 s−1, kOH≈1.5 s−1], in water/DMF Cl− loss is much faster. Thus, the effect on the catalytic rate is more pronounced in DMF. However, the acidic protons lower the overpotential of the catalysis by about 150 mV. 相似文献
47.
L. Pelet L. Grand R. Haller T. B. Bright E. Knecht Eva Hibbert C. Birtwell D. A. Clibbens B. P. Ridge W. D. Bancroft W. M. Clark und W. O. Snelling 《Fresenius' Journal of Analytical Chemistry》1937,109(5-6):235-238
Ohne Zusammenfassung 相似文献
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Laroussi M. Sayler G.S. Glascock B.B. McCurdy B. Pearce M.E. Bright N.G. Malott C.M. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1999,27(1):34-35
Among the various industrial uses of the glow discharge at atmospheric pressure (GDAP), biological applications such as sterilization are under investigation. In this paper, we present images of a liquid medium (Luria-Bertani broth with tetracycline) contaminated by Escherichia coli bacteria (strain PER 322) undergoing plasma treatment. In most cases, it is found that an exposure time of two to 20 minutes leads to nearly a complete kill of a 108/ml E. coli population. The treatment time necessary to obtain a complete kill depends on the plasma power density, the type of gas used, the type of bacteria, and the type of medium 相似文献