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71.
The synthesis of a new halogenide containing hexyltriethylene glycol chain functionalized with biotin is reported. The general possibility of this linker to use as the building block for biotinylated compounds syntheses is demonstrated. Two biotinylated esters with different properties for useful surface modification and as fluorescence probes for proteins marking were synthesized. The properties of mentioned compounds were investigated by using surface plazmon resonance ellypsometry and fluorescence spectroscopy.  相似文献   
72.
73.
This work studies the Soret and Dufour effects on the double-diffusive free convection over a downward-pointing vertical truncated cone with variable wall heat and mass fluxes in fluid-saturated porous media. A coordinate transformation is used to derive the nondimensional boundary-layer governing equations, and the obtained nonsimilar equations are then solved by the cubic spline collocation method. Results for local surface temperature and the local surface concentration are presented as functions of Soret parameters, Dufour parameters, power-law exponents, buoyancy ratios, and Lewis numbers. Results show that increasing the Dufour parameter tends to increase the local surface temperature, while it tends to decrease the local surface concentration. An increase in the Soret number leads to a decrease in the local surface temperature for buoyancy assisting flows, while it leads to an increase in the local surface temperature for buoyancy opposing flows. Increasing the Soret number tends to increase the local surface concentration. Moreover, the local surface temperature and the local surface concentration of the truncated cones with higher power-law exponents are lower than those with lower exponents.  相似文献   
74.
The effects of temperature-dependent viscosity, gravity modulation and thermo-mechanical anisotropies on heat transport in a low-porosity medium are studied using the Ginzburg–Landau model. The effect of gravity modulation is to decrease the Nusselt number, Nu and variable viscosity leads to increase in Nu. The thermo-mechanical anisotropies have opposite effect on Nu with thermal anisotropy decreasing the heat transport.  相似文献   
75.
The solution of cylindrical problems is addressed. A series solution is considered of the biharmonic equation, in which the series terms of the stress function Φ are expressions based upon Legendre polynomials and logarithmically singular functions. An explicit form of a polynomial supplementing each logarithmically singular part of the series solution is obtained.  相似文献   
76.
We consider the flow of a viscous incompressible fluid in a pipe when the boundary is a deformable shell of Naghdi type. We prove that the corresponding system of partial differential equations has a solution when the deformation of the shell is smooth and small enough. We propose an algorithm that uncouples the unknowns and prove its convergence.  相似文献   
77.
We apply the recently improved version of the 0–1 test for chaos to real experimental time series of laser droplet generation process. In particular two marginal regimes of dripping are considered: spontaneous and forced dripping. The outcomes of the test reveal that both spontaneous and forced dripping time series can be characterized as chaotic, which coincides with the previous analysis based on nonlinear time series analysis.  相似文献   
78.
Bockhorst  M.  Burbach  G.  Burgwinkel  R.  Empt  J.  Guse  B.  Guse  B.  Haas  K. -M.  Hannappel  J.  Heinloth  K.  Hey  T.  Hoffmann-Rothe  P.  Honscheid  K.  Jahnen  T.  Jakob  H. P.  Jöpen  N.  Jüngst  H.  Kirch  U.  Klein  F. -J.  Kostrewa  D.  Lindemann  L.  Link  J.  Manns  J.  Menze  D.  Merkel  H.  Merkel  R.  Neuerburg  W.  Paul  E.  Plötzke  R.  Schenk  U.  Schmidt  S.  Scholmann  J.  Schütz  P.  Schultz-Coulon  H. -C.  Schweitzer  M.  Schwille  W. J.  Tran  M. -Q.  Umlauf  G.  Vogl  W.  Wedemeyer  R.  Wehnes  F.  Wißkirchen  J.  Wolf  A. 《Zeitschrift fur Physik C Particles and Fields》1994,63(1):37-47
The reactions pK + and pK + 0 have been measured with the multiparticle detector system SAPHIR at ELSA in Bonn. Besides the differential cross sections the polarization and, for the first time, the 0 polarization have been determined in a photon induced reaction. All data are presented as functions of the photon energy (from threshold up to 1.47 GeV) and of the kaon production angle (0°–180°). The polarization of both and 0 is substantial at all energies and varies strongly with the production angle.This work is supported by the Bundesminister für Forschung und Technologie (BMFT), FK 06 BN 621 I  相似文献   
79.
We consider the spin-averaged nucleon forward Compton scattering amplitude in heavy baryon chiral perturbation theory including all terms to order . The chiral prediction for the spin-averaged forward Compton scattering amplitude is in good agreement with the data for photon energies110 MeV. We also evaluate the nucleon electric and magnetic Compton polarizabilities to this order and discuss the uncertainties of the various counter terms entering the chiral expansion of these quantities.  相似文献   
80.
王梅  贝浼智 《波谱学杂志》1994,11(2):207-210
本文用ESR方法考察了Cp2ZrH) Cl与RNCSR=C6H5,c-C6H11,n-C4H9)的反应的过程,结果表明,在这类反应过程中,Zr-H键发生均裂,中心金属锆经过+4-→+3-→+4的价态变化,反应通过自由基机理进行.  相似文献   
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