Transient mixed convection flow arising due to thermal and mass diffusion over porous sensor surface inside squeezing horizontal channel

The double diffusion effect on the mixed convection flow over a horizontal porous sensor surface placed inside a horizontal channel is analyzed. With the appropriate transformations, the unsteady equations governing the flow are reduced to non-similar boundary layer equations which are solved numerically for the time-dependent mixed convection parameter. The asymptotic solutions are obtained for small and large values of the time-dependent mixed convection parameter. The results are discussed in terms of the skin friction, the heat transfer coefficient, the mass transfer coefficient, and the velocity, temperature, and concentration profiles for different values of the Prandtl number, the Schmidt number, the squeezing index, and the mixed convection parameter.

M7150H×10 Surface Grinder with Horizontal Spindle and Rectangular Table

The 40-year-old Hangzhou MachineTools Works is a special manufacturerof surface grinders. It produces sevenseries with 120 specifications of varioussurface grinders. In addition to meetingdomestic demand, its products have beenexported to some 60 countries and regions,including the USA, the UK, Germany andJapan. The M7150HX10 is one of its exportproducts.

Law of surface movement for multi-coal seam strip mining

It is an important part of green mining to control the disasters of coal mining which have caused irreversible damages to buildings and ecological environment. Strip mining is one of the efficient measures to control surface subsidence and mining damage. However, the research on the laws of the surface subsidence are still deficient in multi-coal seam strip mining at present. Based on the Fast Lagrangian Analysis of Continua(short for FLAC3D) numerical simulation software, the laws of the surface subsidence and horizontal movement were systematically studied for different depths, different mining widths, different distances between seams, different mining thickness, different parameters between seams and the special relations of the upper pillar and the lower pillar in the vertical direction in multi-seam strip mining. The function relation between the maximum subsidence and the maximum horizontal movement with the depth, the mining width, the seam distance, mining thickness, different parameters between seams and the partial offset are summarized respectively. Finally the formula integrating the surface maximum subsidence value and the maximum horizontal movement was deduced. The results can be used for reference theory and measure in forecasting the surface displacement in multi-coal seam strip mining.

H'-splittings of Seifert Manifolds with Boundary

It is known that each compact connected orient able 3-manifold M with boundary admits an H’-splitting H1∪FH2,where F is a compact connected orientable surface properly embedded in M and splits M into two handlbodies H_(1) and H_(2).In this paper,we show that a non-completely L-reducible and minimal H’-splitting surface for a compact connected irreducible orientable anannular Seifert 3-manifold with boundary is horizontal,and give a necessary and sufficient condition for an amalgamation of two compact connected orientable 3-manifolds along a compact connected surface to be a Seifert manifold with boundary,and describe a characteristic of some H’-splittings to denote a Seifert 3-manifold with boundary.For a compact connected orientable Seifert manifold M with a semi-bundle structure M_(1)∪_(F)M_(2),we give an upper bound of the genus of the base surface.