Assessment of the derivative-moment transformation method for unsteady-load estimation

It is often difficult, if not impossible, to measure the aerodynamic or hydrodynamic forces on a moving body. For this reason, a classical control-volume technique is typically applied to extract the unsteady forces. However, measuring the acceleration term within the volume of interest using particle image velocimetry (PIV) can be limited by optical access, reflections, as well as shadows. Therefore, in this study, an alternative approach, termed the derivative-moment transformation (DMT) method, is introduced and tested on a synthetic data set produced using numerical simulations. The test case involves the unsteady loading of a flat plate in a two-dimensional, laminar periodic gust. The results suggest that the DMT method can accurately predict the acceleration term so long as appropriate spatial and temporal resolutions are maintained. The major deficiency, which is more dominant for the direction of drag, was found to be the determination of pressure and unsteady terms in the wake. The effect of control-volume size was investigated, suggesting that larger domains work best by minimizing the associated error in the determination of the pressure field. When decreasing the control-volume size, wake vortices, which produce high gradients across the control surfaces, are found to substantially increase the level of error. On the other hand, it was shown that for large control volumes, and with realistic spatial resolution, the accuracy of the DMT method would also suffer. Therefore, a delicate compromise is required when selecting control-volume size in future experiments.     

Retraction Note to: Thermodynamic study on the interaction of cyanide ion and jack bean urease at different temperatures

Journal of Thermal Analysis and Calorimetry -     

Application of a simple calorimetric data analysis on the binding study of cyanide ions by Jack bean urease

<正>Cyanide ion was studied as an effector of Jack bean urease(JBU) at 300 K in 30 mmol/LTris buffer,pH 7 by isothermal titration calorimetry(ITC).The simple novel model was used for CN~- + JBU interaction over the whole range of CN~- concentrations.The binding parameters recovered from the simple novel model were attributed to the cyanide ion interaction.It was found that cyanide ion acted as a noncooperative inhibitor of JBU,and there is a set of 12 identical and independent binding sites for CN~- ions.The dissociation equilibrium constant is 750μmol/L.The molar enthalpy of binding is△H= -13.6 kJ mol~(-1).The technique used provided an accurate and quick assessment of the effectiveness of the compounds to inhibit Jack bean urease.     

A thermodynamic study on the binding of theophylline with human serum albumin

The thermodynamic parameters of interaction between theophylline and Human Serum Albumin (HSA) in buffer solution (30 mM) of pH = 7 at 27 °C was investigated by isothermal titration calorimetry (ITC). The thermodynamic quantities of the binding mechanism, the number of binding sites (g), the dissociation binding constant (K _d), the molar enthalpy of binding (ΔΗ) and other thermodynamic parameters can be obtained by the extended solvation theory.     

Thermodynamic study on the interaction of cyanide ion and jack bean urease at different temperatures

A method based on Isothermal Titration Calorimety (ITC) is described for the thermodynamic assay of jack bean urease. Inhibitory activity of cyanide ion was examined against jack bean urease (JBU), at 27 and 37 ^oC in 30 mM Tris buffer of pH = 7. The binding parameters of the CN^? + JBU complexation have been calculated. It was found that in the low and high concentrations of the cyanide ions, the JBU structure was destabilized, resulting in a decrease in its biological activity.     

A Structural and Calorimetric Study on the Interaction Between Jack Bean Urease and Cyanide Ion

The cyanide ion was studied as an effecter of Jack bean urease at 300 K in 30 mmol⋅L⁻¹ Tris buffer, pH=7. The inhibition was investigated by isothermal titration calorimetry (ITC). The extended solvation model was used for CN⁻+JBU interaction over the whole range of CN⁻ concentrations. The binding parameters recovered from the solvation model were attributed to the interaction with cyanide ion. It was found that cyanide ion acted as a noncooperative inhibitor of urease, and there is a set of 12 identical and independent binding sites for CN⁻ ions. The dissociation equilibrium constant is 749.99 μmol⋅L⁻¹. The molar enthalpy of binding is ΔH=−13.60 kJ⋅mol⁻¹.