Quality control method of inner surface of valve sleeve in abrasive flow machining

The abrasive flow precision machining(AFPM) method is utilized to smooth the inner wall of the valve sleeve. Through the method of large eddy simulation(LES) and a reasonable subgrid model, numerical simulation analysis is performed on the inner surface of the abrasive flow machining (AFM) valve sleeve to predict the material removal efficiency and surface quality. The effects of wall shear force, dynamic pressure, particle pressure, and vortex on the particle flow are analyzed under different processing parameters. The mechanism of precision machining of the inner wall surface of the valve sleeve by abrasive flow is obtained. The experiment of AFPM was performed by response surface methodology. The results show: The processing pressure and the number of abrasive mesh have a significant impact on the AFM. Through the quadratic response surface plot and contour plot, it is found that the roughness has a minimum point and the best process parameters are obtained. After AFPM, the roughness of the inner wall of the valve sleeve can reach 0.218μm. Finally, the roughness prediction model is established by using the analysis of variance method, and the quality control method of the inner wall surface of the valve sleeve is obtained.

A Novel Quality Control Method for the Determination of the Refractive Index of Oil-in-Water Creams and Its Correlation with Skin Hydration

The sensory properties of cosmetic products can influence consumers’ choice. The accurate correlation of sensory properties, such as skin hydration, with the material properties of the formulation could be desirable. In this study, we aimed to demonstrate a new method for the in vitro measurement of the refractive indices (RIs) of turbid creams. The critical wavelength of each cream was obtained through direct measurement using a sun protection factor (SPF) meter; the wavelength value was then applied in the Sellmeier equation to determine the RI. The results obtained from the in vitro skin hydration measurement for each cream correlated with their RI values. This suggests that RI measurements could be a useful predictive tool for the ranking of creams in terms of their skin hydration effects.

Digital Image Disintegration Analysis: a Novel Quality Control Method for Fast Disintegrating Tablets

Measuring tablet disintegration is essential for quality control purposes; however, no established method adequately accounts for the timeframe or small volumes of the medium associated with the dissipation process for fast disintegrating tablets (FDTs) in the mouth. We hypothesised that digital imaging to measure disintegration in a low volume of the medium might discriminate between different types of FTD formulation. A digital image disintegration analysis (DIDA) was designed to measure tablet disintegration in 0.05–0.7 mL of medium. A temperature-controlled black vessel was 3D-printed to match the dimensions of each tablet under investigation. An overhead camera recorded the mean grey value of the tablet as a measure of the percentage of the formulation which remained intact as a function of time. Imodium Instants, Nurofen Meltlets and a developmental freeze-dried pilocarpine formulation were investigated. The imaging approach proved effective in discriminating the disintegration of different tablets (p < 0.05). For example, 10 s after 0.7 mL of a saliva simulant was applied, 2.0 ± 0.3% of the new pilocarpine tablet remained, whereas at the same time point, 22 ± 9% of the Imodium Instants had not undergone disintegration (temperature within the vessel was 37 ± 0.5°C). Nurofen Meltlets were observed to swell and showed a percentage recovery of 120.7 ± 2.4% and 135.0 ± 6.1% when 0.05 mL and 0.7 mL volumes were used, respectively. Thus, the new digital image disintegration analysis, DIDA, reported here effectively evaluated fast disintegrating tablets and has the potential as a quality control method for such formulations.