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1.
David Hoff 《Journal of Mathematical Fluid Mechanics》2005,7(3):315-338
We prove the global existence of weak solutions of the Navier–Stokes equations of compressible flow in a half-space with the boundary condition proposed by Navier: the velocity on the boundary is proportional to the tangential component of the stress. This boundary condition allows for the determination of the scalar function in the Helmholtz decomposition of the acceleration density, which in turn is crucial in obtaining pointwise bounds for the density. Initial data and solutions are small in energy-norm with nonnegative densities having arbitrarily large sup-norm. These results generalize previous results for solutions in the whole space and are the first for solutions in this intermediate regularity class in a region with a boundary. 相似文献
2.
A data set of 29 experimentally determined Newby shifts in rare-earth nuclei is examined for the reliability of each values.
Using this data set, Newby shifts are obtained which are free from the Coriolis and the particle-particle coupling effects.
These new empirical values help resolve the failure of a recently proposed rule for the sign of the Newby shift in the {5/2[413]p − 5/2[642]n} configuration of160Tb and the {5/2[402]p − 5/2[512]n} configuration of174Lu. Also the Newby shifts are significantly modified in two other cases namely the {1/2[411]p − 1/2[521]n} configuration in168Tm and the {1/2[541]p − 1/2[521]n} configuration in172Lu. Only marginal changes are seen in the rest of the cases in the rare-earth nuclei. 相似文献
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4.
The heats of reaction of tolueneMo(CO)3 with a series of phosphines and phosphites have been measured by solution calorimetry. The order of stability toward formation of fac-(PR3)3Mo(CO)3 in THF solution is: P(OCH3)3s> PMe3 > PnBu3 > PMe2Ph> PEt3 > triphos> P(OPh)3 > PMePh2 > PPh3 > PCl3 and spans a range of 25 kcal/mol reflecting individual bond strength differences up to 8 kcal/mol. The bulky phosphines PCy3 and PtBu3 react with tolueneMo(CO)3 in THF, but 30–40 kcal/mol less heat is evolved in these reactions than with the other phosphines and phosphites. The coordinately unsaturated five-coordinate complexes (PR3)2Mo(CO)3 are proposed as the reaction products. The importance of both steric and electronic factors in the Mo---P bond is discussed. 相似文献
5.
Reaction of HMo(CO)3C5H5 and Sn(C5H5)2 produces the tin hydride HSn[Mo(CO)3C5H5]3 (I). Reaction of I with CCl4, CHCl3, or CH2Cl2 gives ClSn[Mo(CO)3C5H5]3 (II). With hydrogen chloride the hydride I reacts to produce the dichloride Cl2Sn[Mo(CO)3C5H5]2. The first step in this reaction is cleavage of the SnH bond to produce the chloride II. The hydride I reacts with acetic acid to produce the diacetate (CH3COO)2Sn[Mo(CO)3C5H5]2. 相似文献
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7.
Calculations on a system consisting of three electron spins and one nuclear spin are presented and their implications for bacterial photosynthesis discussed. Comparison with experimental measurements of electron spin polarization in pre-reduced photosynthetic reaction centres leads to conclusion that the exchange interaction within the primary radical pair is positive and less than 0.8 mT when the g values of the photoinduced radicals are taken to be those measured for the isolated radical species. 相似文献
8.
Cindy Strehl Timo Gaber Manuela Jakstadt Martin Hahne Paula Hoff Cornelia M. Spies Alexander Scheffold Gerd-Rüdiger Burmester Frank Buttgereit 《Journal of fluorescence》2013,23(3):509-518
Flow cytometry has become a widely-used and powerful tool for the characterization of cells according to their expression of specific proteins. However, sensitivity of this method is still limited since conventionally labeled antibodies can be conjugated with at maximum 1–10 dye molecules. This fact resulted in the need to develop new techniques in order to identify molecules which are expressed in very low but functionally relevant amounts. In the past, we have successfully used a liposome-based high-sensitivity immunofluorescence technique to measure the expression of low abundant membrane bound glucocorticoid receptors (mGR) on different cell types. The use of this technique allows the detection of as few as 50–100 antigen molecules per cell which is due to a 100-fold to 1000-fold increase in fluorescence signal intensity compared with conventional methods. The higher sensitivity is achieved since thousands of dye molecules can be enclosed in liposomes. Another modern high-sensitivity immunofluorescence staining method is the purchasable Fluorescence Amplification by Sequential Employment of Reagents (FASER) procedure. Here, we aimed at comparing sensitivity and specificity of these two techniques for the detection of the mGR. Our data demonstrate the FASER technique to be more sensitive and also more specific for the detection of mGR as compared to the liposome technique. However, both methods have advantages and disadvantages which are discussed in detail. 相似文献
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I. Alfter E. Bodenstedt B. Hamer J. van den Hoff W. Knichel H. Münning S. Piel R. Sajok J. Schüth 《Zeitschrift für Physik A Hadrons and Nuclei》1993,345(3):273-283
Theg-factors of the four lowest states of the ground state rotational band of158Dy have been determined asg(2 1 + )=+0.362(23),g(4 1 su+ )=+0.340(20),g(6 1 su+ )=+0.207(36) andg(8 1 su+ )=+0.21(11). Theg-factors of the 2+ and 4+ states were measured by the IPAC method with radioactive samples of 2.4 h158Er in external magnetic fields. To investigate the higher states, for the first time an on-line γ—γ IPAC experiment was performed with the reaction156Gd(α, 2n)158Dy by use of the static hyperfine field of DyGd. 相似文献