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To research the dynamics of the cavitation bubble under the interaction of particle clusters, the bubble morphological evolutionary characteristics near three equal-sized spherical particles are theoretically explored in the present study based on the Weiss theorem and the velocity potential superposition theory. The three particles are arranged symmetrically, and the fluid velocity field near the three particles and the cavitation bubble is obtained. Moreover, the effects of the bubble-particle distance and the maximum radius of the cavitation bubble on the fluid velocity are investigated, and the contribution mechanisms of the fluid velocity field constituents are compared. The analysis has found that: (1) The fluid velocity between the bubble and the particle is lower than that at the other locations in both the growth and collapse phases, thus the bubble cannot always maintain a standard spherical shape. (2) The bubble-particle distance and the maximum radius of the cavitation bubble are the key parameters affecting the circumferential inhomogeneity of the radial velocity of the fluid around the bubble. The larger the maximum radius or the smaller the bubble-particle distance is, the more visible the non-circularity of the bubble morphology. (3) The image bubbles and the linear sinks contribute oppositely to the fluid velocity field, and the presence of the image bubble reduces the fluid velocity. In the low velocity region, the image bubble is the main mechanism contributing to the effect of the particle on the fluid velocity.

Laser-induced cavitation bubble has been widely used to investigate the mechanisms of hydraulic machinery cavitation erosion and to explore applications in atomization, alloy strengthening, ultrasonic chemistry, biomedicine, surface cleaning and materials processing. This paper consolidates existing research findings on the cavitation bubble dynamics near different boundaries and provides insights for future research work. Firstly, the dynamics of a single cavitation bubble in an infinite field is presented. Subsequently, the focus shifts to the dynamics of cavitation bubble near a rigid wall, angular walls, particles and hydrofoil. Lastly, the paper delves into the dynamics of cavitation bubble within a droplet, revealing the microscopic mechanism of droplet breakup induced by cavitation bubble.

In this paper, the dynamic behaviors of the cavitation bubble near a fixed spherical particle during the second oscillation period are analyzed based on the high-speed photographic system. The deformation and motion of the bubble during the second period are investigated by changing the distance between the particle and the bubble and the maximum radius of the bubble. Meanwhile, the variation of the equivalent radius and the centroid motions are analyzed, and the dynamic behaviors of the bubble are categorized according to the bubble morphological characteristics during the second period. Through this research, it is found that (1) The dynamic behaviors of the bubble during the second oscillation period could be divided into three typical cases: For case 1, a bulge would exist on the bubble interface away from the particle, and for case 2, a bulge would appear on the bubble interface and evolve towards the particle, while for case 3, the bubble would be divided into two parts. (2) The larger the dimensionless distance between the particle and the bubble, the smaller the maximum bubble equivalent radius in the second period, and the shorter the second oscillation period. (3) When the bubble is close to the particle, a counter-jet appears at the bubble interface away from the particle during the rebound stage.

Three classical Fe-MOFs, viz., MIL-100(Fe), MIL-101(Fe), and MIL-53(Fe), were synthesized to serve as platforms for the investigation of structure–activity relationship and catalytic mechanism in the selective conversion of H2S to sulfur. The physicochemical properties of the Fe-MOFs were characterized by various techniques. It was disclosed that the desulfurization performances of Fe-MOFs with well-defined microstructures are obviously different. Among these, MIL-100(Fe) exhibits the highest catalytic performance (ca. 100% H2S conversion and 100% S selectivity at 100–180 °C) that is superior to that of commercial Fe2O3. Furthermore, the results of systematic characterization and DFT calculation reveal that the difference in catalytic performance is mainly because of discrepancy in the amount of Lewis acid sites. A plausible catalytic mechanism has been proposed for H2S selective conversion over Fe-MOFs. This work provides critical insights that are helpful for rational design of desulfurization catalysts.

Classical amino-functionalized Fe-terephthalate metal–organic framework NH2-MIL-53(Fe) and its parent framework MIL-53(Fe) were prepared via simple hydrothermal methods. The catalytic performaces of these two Fe-MOFs were explored for the selective oxidation of H2S. The physicochemical properties of the fresh and used Fe-MOFs catalysts were investigated by XRD, BET, SEM, FT-IR, CO2-TPD, and XPS techniques. It was found that the introduction of amino groups reduces the activation energies for H2S oxidation and endows this catalyst surface with moderate basic sites. As a result, the NH2-MIL-53(Fe) catalyst displays high H2S conversion and near 100% S selectivity in the temperature range of 130–160 °C, outperforming commercial Fe2O3and activated carbon. Moreover, a plausible reaction route for H2S selective oxidation over NH2-MIL-53(Fe) is proposed. This work opens up the possibility of utilizing MOFs as efficient catalyst for desulfuration reactions.

Aim:To evaluate the association between genetic polymorphisms and plasma concentration-to-dose ratio of valproic acid (CDRV) in Chinese epileptic patients. Methods:A total of 46 epileptic patients treated with valproic acid therapy were enrolled. 18 SNPs in nine genes related to valproic acid were directly sequenced with Sanger methods. Results:Patients carrying UGT1A6heterozygous genotypes had significantly lower CDRV than those carrying the wild-type genotypes. In contrast, patients with the homozygote genotypes of CYP2C9and ABAThad higher CDRV than those with the wild-type genotypes, and patients with the heterozygous genotypes of CYP2C19had higher CDRV. Conclusion:Detection of genetic polymorphism in these genes might facilitate an appropriate dose of valproic acid for epileptic patients. Further studies with larger cohorts are necessary to underpin these observations.

Rat renal tubular epithelial cell (RTEC) cultured with high glucose has been used to observe the protective effect of Ginkgo biloba extract (GBE) against diabetic nephropathy (DN). The compounds in GBE binding with cell membrane or entering into cell are still unknown, which may be potential bioactive components. In this paper, a powerful method for screening and analyzing the potential bioactive components from GBE was developed using cell extraction coupled with high performance liquid chromatography tandem mass spectrometry (LC-MS/MS). 8 prototype compounds and 5 metabolites were obtained, among which 6 prototype compounds and 1 metabolite were identified or tentatively characterized as rutin, bilobalide, ginkgolide B, ginkgolide C, genkwanin, apigenin and diosmetin by comparing their retention times and MS spectra with those of authentic standards or literature data. The 6 prototype compounds were further quantitatively analyzed using electrospray ionization in negative mode multiple reaction monitoring (MRM). The results showed that high glucose changed the Tmax, MRT(0-t), Cmax and AUC(0-t) of all observed compounds and decreased the t1/2 of genkwanin and apigenin, significantly. The overall findings indicate that 8 prototype compounds may be the potential bioactive components of GBE with preventive effect against DN and the method of RTEC extraction coupled with LC-MS/MS technology screening method we developed is a feasible, rapid, and useful tool for screening and analyzing potential bioactive components.

In this study, a new energetic hybrid skeleton was constructed through the integration of nitropyrazole and 1,3,4-oxadiazole skeletons in a molecule. Furthermore, the energetic precursor (2), the azo-bridged compound (3), the neutral nitramine (4) and the corresponding energetic salts (5–7) were synthesized. Their physicochemical and energetic properties were experimentally and theoretically evaluated. Among the developed compounds, the azo-bridged compound (3) and dihydroxylammoinium (6) display high detonation performances (3, Dv = 8904 m/s, P = 34.47 GPa; 6, Dv = 9025 m/s, P = 34.66 GPa), moderate sensitivities (3, IS = 16 J, FS = 120 N; 6, IS = 20 J, FS = 312 N) and good densities (3, 1.87 g/cm3; 6, 1.81 g/cm3), which indicates that they have the potential to replace the traditional high-energy explosive RDX. The results showed that the integration of different energetic skeletons can achieve a good balance between energy and sensitivity.