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141.
Guang Yang Bernhard Weigand Alexandros Terzis Kilian Weishaupt Rainer Helmig 《Transport in Porous Media》2018,122(1):145-167
This study investigates numerically the turbulent flow and heat transfer characteristics of a T-junction mixing, where a porous media flow is vertically discharged in a 3D fully developed channel flow. The fluid equations for the porous medium are solved in a pore structure level using an Speziale, Sarkar and Gatski turbulence model and validated with open literature data. Overall, two types of porous structures, consisted of square pores, are investigated over a wide range of Reynolds numbers: an in-line and a staggered pore structure arrangement. The flow patterns, including the reattachment length in the channel, the velocity field inside the porous medium as well as the fluctuation velocity at the interface, are found to be strongly affected by the velocity ratio between the transversely interacting flow streams. In addition, the heat transfer examination of the flow domain reveals that the temperature distribution in the porous structure is more uniform for the staggered array. The local heat transfer distributions inside the porous structure are also studied, and the general heat transfer rates are correlated in terms of area-averaged Nusselt number accounting for the effects of Reynolds number, velocity ratio as well as the geometrical arrangement of the porous structures. 相似文献
142.
S. Abd El-Samad R. Bilger K. -Th. Brinkmann H. Clement M. Dietrich E. Doroshkevich S. Dshemuchadse K. Ehrhardt A. Erhardt W. Eyrich A. Filippi H. Freiesleben M. Fritsch R. Geyer A. Gillitzer J. Hauffe D. Hesselbarth R. Jaekel B. Jakob L. Karsch K. Kilian J. Kress E. Kuhlmann S. Marcello S. Marwinski R. Meier K. M?ller H. P. Morsch L. Naumann J. Ritman E. Roderburg P. Sch?nmeier M. Schulte-Wissermann W. Schroeder F. Stinzing G. Y. Sun J. W?chter G. J. Wagner M. Wagner U. Weidlich A. Wilms S. Wirth G. Zhang P. Zupranski 《The European Physical Journal A - Hadrons and Nuclei》2009,39(3):281-289
The single-pion production reactions pp
d
, pp
np
and pp
pp
were measured at a beam momentum of 0.95GeV/c ( T
p
400 MeV) using the short version of the COSY-TOF spectrometer. The central calorimeter provided particle identification,
energy determination and neutron detection in addition to time-of-flight and angle measurements from other detector parts.
Thus all pion production channels were recorded with 1-4 overconstraints. The main emphasis is put on the presentation and
discussion of the np
channel, since the results on the other channels have already been published previously. The total and differential cross-sections
obtained are compared to theoretical calculations. In contrast to the pp
channel we observe in the np
channel a strong influence of the excitation. In particular, the pion angular distribution exhibits a (3 cos2
+ 1) -dependence, typical for a pure s -channel excitation and identical to that observed in the d
channel. Since the latter is understood by a s -channel resonance in the 1
D
2
pn partial wave, we discuss an analogous scenario for the pn
channel. 相似文献
143.
M. Abdel-Bary K. -Th. Brinkmann H. Clement E. Doroshkevich S. Dshemuchadse A. Erhardt W. Eyrich H. Freiesleben A. Gillitzer R. Jäkel L. Karsch K. Kilian E. Kuhlmann K. Möller H. P. Morsch L. Naumann N. Paul C. Pizzolotto J. Ritman E. Roderburg W. Schroeder M. Schulte-Wissermann Th. Sefzick A. Teufel A. Ucar W. Ullrich P. Wintz P. Wüstner P. Zupranski 《The European Physical Journal A - Hadrons and Nuclei》2008,36(1):7-16
The quasifree reaction
was studied in a kinematically complete experiment by bombarding a liquid-hydrogen target with a deuteron beam of momentum
1.85GeV/c and analyzing the data along the lines of the spectator model. In addition to the three charged ejectiles the spectator proton
was also detected in the large-acceptance time-of-flight spectrometer COSY-TOF. It was identified by its momentum and flight
direction thus yielding access to the Fermi motion of the bound neutron and to the effective neutron 4-momentum vector
n which differed from event to event. A range of almost 90MeV excess energy above threshold was covered. Energy-dependent angular
distributions, invariant-mass spectra as well as fully covered Dalitz plots were deduced. Sizeable pp FSI effects were found as were contributions of p and d partial waves. In comparison with existing literature data the results provide a sensitive test of the spectator model. The
behavior of the elementary cross-section σ01 close to threshold is discussed in view of new cross-section data. 相似文献
144.
145.
Porphyrin ligands, showing a significant affinity for cancer cells, also have the ability to chelate metallic radioisotopes to form potential diagnostic radiopharmaceuticals. They can be applied in single-photon emission computed tomography (SPECT) and positron emission tomography (PET) to evaluate metabolic changes in the human body for tumor diagnostics. The aim of this paper is to present a short overview of the main metallic radionuclides complexed by porphyrin ligands and used in these techniques. These chelation reactions are discussed in terms of the complexation conditions and kinetics and the complex stability. 相似文献
146.
Kilian Roßmann Kerem C. Akkaya Pascal Poc Corentin Charbonnier Jenny Eichhorst Hannes Gonschior Abha Valavalkar Nicolas Wendler Thorben Cordes Benjamin Dietzek-Ivani Ben Jones Martin Lehmann Johannes Broichhagen 《Chemical science》2022,13(29):8605
Rhodamine fluorophores are setting benchmarks in fluorescence microscopy. Herein, we report the deuterium (d12) congeners of tetramethyl(silicon)rhodamine, obtained by isotopic labelling of the four methyl groups, show improved photophysical parameters (i.e. brightness, lifetimes) and reduced chemical bleaching. We explore this finding for SNAP- and Halo-tag labelling in live cells, and highlight enhanced properties in several applications, such as fluorescence activated cell sorting, fluorescence lifetime microscopy, stimulated emission depletion nanoscopy and single-molecule Förster-resonance energy transfer. We finally extend this idea to other dye families and envision deuteration as a generalizable concept to improve existing and to develop new chemical biology probes.Deuteration enhances photophysical and chemical properties of fluorescent rhodamine dyes for higher brightness in sensitive microscopy. 相似文献
147.
148.
149.
Reactions of the oxide sulphates M2IIIO2SO4 of La, Pr, Nd, Sm, Gd, Dy, Er, Yb and Y with hydrogen chloride between 450 and 600°C are described. The temperature dependence of reaction course is comparable with that of rare earth's oxides reactions with hydrogen chloride. 相似文献
150.