Simulation research on aerodynamic noise characteristics of a compressor under different working conditions.

The shear stress transport turbulence model is employed to conduct a detailed study of flow characteristics at the highest efficiency point and near-stall point in a full-channel 1.5-stage compressor in this paper. The simulation results for the compressor's total pressure ratio and efficiency exhibit good agreement with experimental data.

Application of X-ray fluorescence spectrometry for screening pharmaceutical products for Elemental Impurities according to ICH guideline Q3D.

Energy-dispersive X-ray fluorescence spectrometry (EDXRF) is a suitable analytical procedure for screening drug products for Elemental Impurities (EI) according to ICH guideline Q3D. EDXRF represents a cost-efficient, robust and standard-free alternative compared to other methodologies for trace analysis, and therefore utilization of this application should be encouraged. This study demonstrates the capability of EDXRF for EI screening of oral solid dosage drug products (OSD products) within a defined matrix range.

VO supported on TiO-CeZrO core-shell structure catalyst for NH-SCR of NO.

In this experiment, a TiO-CeZrO support with core-shell structure was successfully prepared by a precipitation method and VO /TiO-CeZrO catalyst was prepared by an impregnation method, and the catalyst was used to catalyze the NH-SCR of NO. Based on the results of HRTEM, XRD, BET, H-TPR, NH-TPD, XPS, Py-IR, it was speculated that due to the interaction between TiO and CeZrO, more oxygen vacancies and Ce are generated, which are beneficial to the existence of low-valence V by electron transfer between high valence state V and Ceand increase the acidic sites on the catalyst surface. The catalytic activity (>97%) of the VO /TiO-CeZrO catalyst is superior to the current commercial catalyst (VO-WO/TiO) and has a higher N selectivity (>97.

A relationship between the V/V ratio and the surface dispersion, surface acidity, and redox performance of VO-WO/TiO SCR catalysts.

A series of VO-WO/TiO catalysts with different vanadium loading amounts were prepared by an impregnation method and were characterized by XRD, Raman spectroscopy, XPS, DRIFTS, Py-DRIFTS, NH-TPD, H-TPR, The results show that the catalytic activity is related to the ratio of V/V. The variation of the V/V ratio caused by the different dispersion states of vanadia oxide leads to changes in the surface acidity and redox properties of the catalysts. As the V/V ratio reaches the maximum value, the apparent activation energy ( ) required to form the transition state on the Brønsted acid sites is the lowest.

A Miniaturized QEPAS Trace Gas Sensor with a 3D-Printed Acoustic Detection Module.

A 3D printing technique was introduced to a quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor and is reported for the first time. The acoustic detection module (ADM) was designed and fabricated using the 3D printing technique and the ADM volume was compressed significantly. Furthermore, a small grin lens was used for laser focusing and facilitated the beam adjustment in the 3D-printed ADM.