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151.
Aleks Ponjavic Luca di Mare Janet S. S. Wong 《Journal of Polymer Science.Polymer Physics》2014,52(10):708-715
The rheology of submicron thick polymer melt is examined under high normal pressure conditions by a recently developed photobleached‐fluorescence imaging velocimetry technique. In particular, the validity and limitation of Reynold equation solution, which suggests a linear through‐thickness velocity profile, is investigated. Polybutene (PB) is sheared between two surfaces in a point contact. The results presented in this work suggest the existence of a critical pressure below which the through‐thickness velocity profile is close to linear. At higher pressures however, the profile assumes a sigmoidal shape resembling partial plug flow. The departure of the sigmoidal profile from the linear profile increases with pressure, which is indicative of a second‐order phase/glass transition. The nature of the transition is confirmed independently by examining the pressure‐dependent dynamics of PB squeeze films. The critical pressure for flow profile transition varies with molecular weight, which is consistent with the pressure‐induced glass transition of polymer melt. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 708–715 相似文献
152.
Nils Pfullmann Monika Noack José Cardoso de Andrade Stefan Rausch Tamas Nagy Carsten Reinhardt Vanessa Knittel Rudolf Bratschitsch Alfred Leitenstorfer Dieter Akemeier Andreas Hütten Milutin Kovacev Uwe Morgner 《Annalen der Physik》2014,526(3-4):119-134
High‐order harmonic generation in xenon with oscillator repetition rates is studied. The necessary intensity is reached via plasmonic field enhancement at nanostructured arrays of bow‐tie gold antennae. The theoretical analysis focuses on the thermal properties and the damage threshold of the bow‐tie antennae. On the experimental side the number of contributing atoms is determined and optimized. Extreme ultraviolet radiation is successfully observed with photon fluxes almost an order of magnitude larger than previously reported. 相似文献
153.
Francis B. Dejene Abdub G. Ali Hendrik C. Swart Reinhardt J. Botha Kittesa Roro Liza Coetsee Mart M. Biggs 《Central European Journal of Physics》2011,9(5):1321-1326
Material property dependence on the OH−/Zn2+ molar ratio of the precursor was investigated by varying the amount of NaOH during synthesis of ZnO. It was necessary to
control the water content and temperature of the mixture to ensure the reproducibility. It was observed that the structural
properties, particle size, photoluminescence intensity and wavelength of maximum intensity were influenced by the molar ratio
of the precursor. The XRD spectra for ZnO nanoparticles show the entire peaks corresponding to the various planes of wurtzite
ZnO, indicating a single phase. UV measurements show the absorption that comes from the ZnO nanoparticles in visible region.
The absorption edge of these ZnO nanoparticles are shifted to higher energies and the determined band gap energies are blue
shifted as the OH−/Zn2 molar ration increases, due to the quantum confinement effects. The photoluminescence characterization of the ZnO nanostructures
exhibited a broad emission band centred at green (600 nm) region for all molar ratios except for OH−/Zn2+ = 1.7 where a second blue emission around 468 nm was also observed. The photoluminescence properties of ZnO nanoparticles
were largely determined by the size and surface properties of the nanoparticles. 相似文献
154.
Markov A Reinhardt C Ung B Evlyukhin AB Cheng W Chichkov BN Skorobogatiy M 《Optics letters》2011,36(13):2468-2470
A type of a plasmonic waveguide has been proposed featuring an "open" design that is easy to manufacture, simple to excite and offers convenient access to a plasmonic mode. Optical properties of photonic bandgap (PBG) plasmonic waveguides are investigated experimentally by leakage radiation microscopy and numerically using the finite element method confirming photonic bandgap guidance in a broad spectral range. Propagation and localization characteristics of a PBG plasmonic waveguide have been discussed as a function of the wavelength of operation, waveguide core size, and the number of ridges in the periodic reflector for fundamental and higher order plasmonic modes of the waveguide. 相似文献
155.
Dr. Sebastian Götze Dr. Nahid Azzouz Dr. Yu‐Hsuan Tsai Prof. Dr. Uwe Groß Anika Reinhardt Dr. Chakkumkal Anish Prof. Dr. Peter H. Seeberger Dr. Daniel Varón Silva 《Angewandte Chemie (International ed. in English)》2014,53(50):13701-13705
Around 2 billion people worldwide are infected with the apicomplexan parasite Toxoplasma gondii which induces a variety of medical conditions. For example, primary infection during pregnancy can result in fetal death or mental retardation of the child. Diagnosis of acute infections in pregnant women is challenging but crucially important as the drugs used to treat T. gondii infections are potentially harmful to the unborn child. Better, faster, more reliable, and cheaper means of diagnosis by using defined antigens for accurate serological tests are highly desirable. Synthetic pathogen‐specific glycosylphosphatidylinositol (GPI) glycan antigens are diagnostic markers and have been used to distinguish between toxoplasmosis disease states using human sera. 相似文献
156.
157.
H. Reinhardt 《Annalen der Physik》1988,500(5):367-371
A generalized heat kernel method which includes space-time dependent scalar fields as mass scale already in zero order is presented. The approach is illustrated by calculating the vacuum polarization of a coupled meson-fermion theory exhibiting soliton type of solutions. 相似文献
158.
I. David Bough Jr. Reinhardt J. Heuer Robert Thayer Sataloff James R. Hills Jacqueline R. Cater 《Journal of voice》1996,10(2):166-174
Recent advances in the diagnosis and treatment of voice disorders necessitate the need for accurate and reliable objective voice measurements. There are many instruments commonly used to analyze voice data. Many, if not most, of these instruments have not been adequately tested for reliability or consistency. This study evaluates the intrasubject variability of the objective voice measurements from two commonly used voice analysis instruments. The study also presents data correlating subjective mood states, room temperatures, sleep times of the subject, time since last meal, and hydration levels to the various acoustic measures. Several weak but significant correlations were obtained and are discussed. Guidelines for the appropriate use of these instruments are described. 相似文献
159.
K. Schiffer A. Dewald A. Gelberg R. Reinhardt K. O. Zell Sun Xianfu P. von Brentano 《Zeitschrift für Physik A Hadrons and Nuclei》1987,327(3):251-265
High spin states of126Ba have been populated via the116Sn (13C, 3n) reaction and were investigated by inbeam gamma-ray spectroscopy. Partially NaJ (Tl)-BGO anti-compton shields were used. Two positive parity band crossings were established. The yrast band was observed up to a tentative 18+ level. The gamma-bands and two band structures of negative parity were found. In addition a tentative 3? state has been seen. Two-quasiparticle Routhians are constructed from the one-quasiparticle Routhians of the bands in the odd neighbouring isotopes and isotones and are compared to the ones observed in126Ba. This leads to ah 11/2 g 7/2-neutron structure of the strongly coupled negative parity bands and a two-quasiproton structure of the decoupled bands of negative parity. The branching and mixing ratios for the neutron bands are analyzed. 相似文献
160.