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21.
Journal of Applied and Industrial Mathematics - Under consideration is the well-known boundary value problem of aerohydrodynamics in which it is required to find the velocity distribution of fluid...  相似文献   
22.
Russian Physics Journal - The spectroscopic characteristics of mono and binuclear difluoroborate complexes of dipyrromethenes in various solvents and solid-state polymer media (films) are...  相似文献   
23.
Russian Physics Journal - The effect of low-energy oxygen ion irradiation on the composition and some properties of the layer formed on the thallium surface is studied. It is shown that the...  相似文献   
24.
Journal of Experimental and Theoretical Physics - The yields of alpha particles and neutrons from the promising 11B(p, 3α) fusion reaction and the reference 11B(p, n)11C nuclear reaction,...  相似文献   
25.
JETP Letters - The electronic and transport properties of new hybrid 2D–1D–2D structures of carbon atoms, which are graphene sheets continuously connected through a fragment of a...  相似文献   
26.
Acoustical Physics - A spectral algorithm is considered for describing nonlinear generation of an acoustic wave of difference frequency formed as the interaction of two high-intensity pump waves...  相似文献   
27.

The catalytic activity of the systems based on titanium(iv) alkoxides (Ti(OPri)4, Ti(OPri)2(OCH(CF3)2)2, and Ti(OCH(CF3)2)4) and mixtures of alkylaluminum chlorides (Et2AlCl or Et3Al2Cl3) with dibutylmagnesium in ethylene polymerization and ethylene copolymerization with propylene and 5-ethylidene-2-norbornene was studied. Ultrahigh-molecular-weight polyethylene with the molecular weight reaching 4.9 · 106 Da was found to be formed in the homopolymerization reaction, whereas copolymerization gives ter-copolymers containing propylene (up to 35 mol.%) and 5-ethylidene-2-norbornene (4.3 mol.%) units.

  相似文献   
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29.
A theoretical study is presented of peristaltic hydrodynamics of an aqueous electrolytic non-Newtonian Jeffrey bio-rheological fluid through an asymmetric microchannel under an applied axial electric field. An analytical approach is adopted to obtain the closed form solution for velocity, volumetric flow, pressure difference and stream function. The analysis is also restricted under the low Reynolds number assumption (Stokes flow) and lubrication theory approximations (large wavelength). Small ionic Peclét number and Debye–Hückel linearization (i.e. wall zeta potential ≤ 25 mV) are also considered to simplify the Nernst–Planck and Poisson–Boltzmann equations. Streamline plots are also presented for the different electro-osmotic parameter, varying magnitudes of the electric field (both aiding and opposing cases) and for different values of the ratio of relaxation to retardation time parameter. Comparisons are also included between the Newtonian and general non-Newtonian Jeffrey fluid cases. The results presented here may be of fundamental interest towards designing lab-on-a-chip devices for flow mixing, cell manipulation, micro-scale pumps etc. Trapping is shown to be more sensitive to an electric field (aiding, opposing and neutral) rather than the electro-osmotic parameter and viscoelastic relaxation to retardation ratio parameter. The results may also help towards the design of organ-on-a-chip like devices for better drug design.  相似文献   
30.
Journal of Radioanalytical and Nuclear Chemistry - The present study focuses on the effect of natural radioactivity of some common building materials to humans. The main radiological risk...  相似文献   
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