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1.
The aim of this Letter is to show that, the Nusselt number sign might be changed without changing of heat transfer direction at the wall of channels, even for flows without viscous dissipation. 相似文献
2.
Burak Sabuncu Fazilet Zumrut Biber Muftuler Ayfer Yurt Kilcar Betul Cekic Eser Ucar Perihan Unak 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(3):1021-1026
People drink various types of tea without knowing the side effects of biological and chemical contents and radiopharmaceutical interactions. In current study, it is aimed to evaluate the effects of green tea extract in different extraction solvents on the radiolabeling of the blood constituents with 99mTc and on the biodistribution of radiopharmaceutical sodium pertechnetate (Na99mTcO4) in male Wistar Albino rats. The extraction of green tea was performed in different solvents. Biodistribution studies were performed on male rats which were treated via gavage with green tea extract in different extraction solvents or saline (0.9 % NaCl) as a control group for 7 days. The radiolabeling of blood constituents performed incubating with SnCl2 and 99mTc. According to experimental results, radiolabeling blood components with 99mTc were not modified in the usage of the different extraction solvents for green tea extraction, but a significant alteration (P < 0.05) of biodistribution of Na99mTcO4 was observed after treatment with green tea extract in distilled water. Although there is no considerable effect on radiolabeling of blood components, there is an outstanding change on the biodistribution studies especially with green tea extract in distilled water. The identified change monitored in this study may cause to reduce the risk of misdiagnosis and/or avoid the repetition of the examinations in nuclear medicine. 相似文献
3.
The MeOH extracts of wood and bark from Quercus hartwissiana have been investigated by GC-MS after derivatization, as well
as by classical spectroscopic methods. The results for the free compounds revealed that ellagic acid, catechin, gallic acid,
quercitol, and also long chain fatty acids, sugars, and sitosterol were the essential compounds in wood and bark, most of
them being present in differing amounts. Quercitol, a characteristic compound for the oak wood tannin, was also recognized
and determined in oak bark extracts in this study. Amounting to 1/4th to 1/3rd of the free compounds, the bark had the highest catechin content. While the content of sugars, such as fructose and glucose,
increased in sapwood and bark extracts remarkably, the amounts of these compounds decreased in extracts of heartwood. The
profile of the bound compounds contained sugars (i.e., arabinose, xylose, and, above all, glucose), ellagic and gallic acids,
quercitols, and inositols. Compared with the composition of free compounds, the hydrolyzed extracts showed relatively higher
amounts of sugars, especially glucose, gallic acid and quercitol. 相似文献
4.
5.
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 P. Schönmeier W. Schroeder M. Schulte-Wissermann G. Y. Sun A. Teufel A. Ucar G. J. Wagner M. Wagner P. Wintz P. Wüstner P. Zupranski 《The European Physical Journal A - Hadrons and Nuclei》2006,29(3):353-361
The reaction
has been studied in a kinematically complete experiment at a single beam momentum
GeV/c (T = 759MeV). All four ejectiles have been detected in the large-acceptance time-of-flight spectrometer COSY-TOF. We analyzed
the data along the lines of the spectator model as a means to isolate the quasi-free
reaction. The spectator proton was identified by its momentum and flight direction thus yielding access to the associated
Fermi motion of the bound neutron. A comparison is carried out with Monte Carlo simulations based on two different parameterizations
of the deuteron wave function. Up to a Fermi momentum of roughly 150MeV/c no significant deviations between experimental and simulated data of various observables were found from which we conclude
that the deuteron can indeed be taken as a valid substitute for the neutron. 相似文献
6.
7.
A nanocomposite (Ho2O3NPs/BNT) was synthesized by decorating holmium(III)oxide nanoparticles (H2O3NPs) on bentonite (BNT) through a realizable sonochemical approach for the electrochemical detection of haloperidol (Hlp). A glassy carbon electrode was modified with this nanocomposite. The Ho2O3NPs/BNT modified electrode outperformed bare and other modified electrodes in terms of electrochemical performance for Hlp detection in a pH 8.0 phosphate buffer. The proposed electrochemical platform showed a wide linear range (0.01 μM–24 μM), low detection limit (2.4 nM), and high sensitivity by square wave voltammetry. In addition, the proposed electrochemical sensor met the clinical criteria in terms of stability, selectivity, and repeatability. 相似文献
8.
Experimental investigation of inclined liquid water jet flow onto vertically located superhydrophobic surfaces 总被引:1,自引:0,他引:1
Ali Kibar Hasan Karabay K. Süleyman Yiğit Ikrime O. Ucar H. Yıldırım Erbil 《Experiments in fluids》2010,49(5):1135-1145
In this study, the behaviour of an inclined water jet, which is impinged onto hydrophobic and superhydrophobic surfaces, has
been investigated experimentally. Water jet was impinged with different inclination angles (15°–45°) onto five different hydrophobic
surfaces made of rough polymer, which were held vertically. The water contact angles on these surfaces were measured as 102°,
112°, 123°, 145° and 167° showing that the last surface was superhydrophobic. Two different nozzles with 1.75 and 4 mm in
diameters were used to create the water jet. Water jet velocity was within the range of 0.5–5 m/s, thus the Weber number varied
from 5 to 650 and Reynolds number from 500 to 8,000 during the experiments. Hydrophobic surfaces reflected the liquid jet
depending on the surface contact angle, jet inclination angle and the Weber number. The variation of the reflection angle
with the Weber number showed a maximum value for a constant jet angle. The maximum value of the reflection angle was nearly
equal to half of the jet angle. It was determined that the viscous drag decreases as the contact angle of the hydrophobic
surface increases. The drag force on the wall is reduced dramatically with superhydrophobic surfaces. The amount of reduction
of the average shear stress on the wall was about 40%, when the contact angle of the surface was increased from 145° to 167°.
The area of the spreading water layer decreased as the contact angle of the surface increased and as the jet inclination angle,
Weber number and Reynolds number decreased. 相似文献
9.
Two conjugates of tetraphenylethylene with d-2′-deoxyuridine (1d) and l-2′-deoxyuridine (1l) were synthesized to construct new supramolecular DNA-architectures by self-assembly. The non-templated assemblies of 1d and 1l show strong aggregation-induced emission and their chirality is exclusively controlled by the configuration of their sugar part. In contrast, the chirality of the DNA-templated assemblies is governed by the configuration of the DNA, and there is no configuration-selective binding of 1d to d-A20 and 1l to l-A20. The quantum yield of the assembly of 1d along the single-stranded DNA A20 is 0.40; approximately every second available binding site on the DNA template is occupied by 1d. The strong aggregation-induced emission of these DNA architectures can be efficiently quenched and the excitation energy can be transported to Atto dyes at the 5′-terminus. A multistep energy transport “hopping” precedes the final energy transfer to the terminal acceptor. The building block 1d promotes this energy transport as stepping stones. This was elucidated by reference DNA double strands in which 1d was covalently incorporated at two distinct sites in the sequences, one near the Atto dye, and one farther away. This new type of completely self-assembled supramolecular DNA architecture is hierarchically ordered and the DNA template controls not only the binding but also the energy transport properties. The high intensity of the aggregation-induced emission and the excellent energy transport properties make these DNA-based materials promising candidates for optoelectronic applications.DNA architectures with tetraphenylethylene are assembled in a non-covalent way. The strong aggregation-induced emission of the chromophores is quenched and the energy is transported to Atto dyes by a multistep energy “hopping”. 相似文献
10.
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