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The three-dimensional flow structure induced by normal shock wave/turbulent boundary-layer interaction in a constant-area rectangular duct at Ma= 1.68 is numerically investigated by using the Reynolds Stress Model and κ-ω SST turbulent model. In comparison with SST model, the RSM model resolves secondary flow effects, and therefore a reduced corner separation zone is acquired. This leads to a better match between the experimental data and the RSM results. Under the effect of the wall friction due to viscosity, the shocks of shock train will bifurcate near both top/bottom walls and side walls, and the three-dimensional "λ" shock waves are formed at the duct corner. In the position close to the wall, the foreleg shock of the first "λ" shock splits and a new smaller "λ" shock wave is observed. [ABSTRACT FROM AUTHOR]

The flow over a hypersonic jaws inlet was experimentally and numerically studied. Flow characteristics in hypersonic jaws inlets have been presented by theoretic, experimental and numerical methods. The experimental method and technology of high-contraction-ratio jaws inlet in hypersonic wind tunnel was given to acquire the experimental data of starting inlet. Numerical results demonstrated that a pair of three-dimensional vortical structures for mixing enhancement was formed as a result of the pitch and yaw shock waves/boundary-layer interactions, and the mechanism for the 3D flow structure was explained by analyzing the streamlines distributions in boundary layer around the cowl. [ABSTRACT FROM AUTHOR]

A supersonic combustion flow analysis model with shock train structure has been developed to support airbreathing hypersonic vehicle design optimization studies. The model solves a stiff set of ordinary differential equations coupled with the equations for finite-rate chemistry to describe the aerothermodynamics of ignition and combustion process within the supersonic combustor. The Billig's shock train model is used to simulate upstream propagation of high pressure within the combustor. The calculation of H2/air supersonic combustion flowfield in three typical combustors with "a constant-area section+an expansion section", "backward-facing step", "strut injection" is used to validate the supersonic combustion model. The results show that the model presented explains accurately physical chemistry phenomena in supersonic combustion flowfield. Comparison with experimental data shows that the pressure distribution calculated by new model is closer to the experimental result than the previous model without shock train structure. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of isopsoralen on proliferation, osteogenic differentiation and calcification capacity of rat calvarial osteoblasts (ROB)., Methods: Segregated neonatal SD rat skull,and digestion with enzyme to obtain bone cells and cultured in MEM containing 10% FBS. Exchange the medium after three days, proceeded serial subcultivation when cells covered with 90% culture dish. Proliferation analysis was performed in 96-well plates use MTT method, isopsoralen's final concentration were 1 x 10(-4), 1 x10(-5), 1 x 10(-6), 1 x 10(-7) mmol/L. Differentiation analysis was performed in 24-well plates, the Alkaline phosphatase activity and calcium salt sediment yield and osteocalcin measured at the 4th, 8th, 12th, 16th day. At 12th day, proceeded ALP stain, and at 14th day for alizarin red staining and calcified nodule count., Results: When the Isopsoralen's final concentration was 1 x 10(-5) mmol/L, there was no significant effect on the ROB's proliferation, but it could promote osteogenesis. It also could raise the ALP activity and calcium salt sediment yield and osteocalcin, increase calcified tubercle amount., Conclusion: When the isopsoralen final concentration is 1 x 10(-5) mmol/L, it promoted ROB differentiation and maturation. Isopsoralen may be the active ingredients of preventing anti-osteoporosis in Psoralea corylifolia.

Objective: To investigate the effects of total flavonoid extract of Epimedium sagittatum (TFE) on the proliferation and differentiation of newborn rat calvarial osteoblasts (ROB)., Method: TFE was supplemented into the culture medium of ROB at 0. 1, 1, 10 and 100 microg x mL(-1) respectively. The serum of rats administered TFES (SRAT) was also added into the medium in a parallel treatment at 2.5%, 5% and 10% respectively. Their effects on cell proliferation and differentiation was studied by MTT and the analysis of osteogenic differentiation marks., Result: TFE had no appreciable and on cell proliferation and differentiation at any concentration. However, 2.5% and 5% SRAT stimulated cell proliferation strongly and, 5% SRAT significantly promoted the maturation and function of osteoblast by improving the alkaline phosphatase activity, osteocalcin secretion, calcium deposition and the number of mineralized nodular structures., Conclusion: The metabolites of TFE should be the anti-osteoporosis constitutes of Epimedium sagittatum.