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Yttrium oxide (Y 2 O 3) nanoparticles have critical applications in many industries, including ceramics, optics, and biomedicine. However, conventional synthesis methods are typically cumbersome and time-consuming. Herein, a novel emulsion detonation method successfully achieved the one-step synthesis of Y 2 O 3 nanoparticles. In this method, yttrium nitrate hexahydrate was uniformly dispersed in the emulsion explosive as a precursor and an auxiliary oxidizer. After the emulsion explosive was detonated in a detonation chamber, the detonation products were collected, purified and characterized by X-ray diffraction, Fourier transform infrared spectrometer, Raman spectrometer, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, field emission transmission electron microscopy, and ultraviolet spectrophotometer. The results show that the as-synthesized powders are high-purity cubic phase yttrium oxide nanoparticles with a spherical-like morphology and an average particle size of approximately 30 nm. These Y 2 O 3 nanoparticles have a wide (5.53 eV) energy band gap, close to the conventional methods. Based on detonation theory, thermochemical theory, and characterization results, this text discussed the mechanism of the Y 2 O 3 nanoparticles synthesized by the emulsion detonation method. During detonation, the formation of the Y 2 O 3 nanoparticles underwent three stages: the formation of the Y 2 O 3 molecules by the collision of Y and O ions, the formation of the crystal nucleus at supersaturation concentration, and crystal growth. This study provides a novel, cost-effective method for efficiently synthesizing Y 2 O 3 nanoparticles. [ABSTRACT FROM AUTHOR]

Near-infrared responsive photothermal therapy is an emerging and non-invasive cancer treatment. However, the inability of real-time imaging tracking and monitoring for the photothermal agents (PTAs) severely limits the accuracy of treatment. In this study, a series of visual xGd-WO 3 @PEG PTAs were synthesized by a one-pot solvothermal method. The effect of different Gd doping amounts on the structure, morphology, and photothermal performance has been investigated in detail. Under the near-infrared laser irradiation, the samples exhibited satisfied photothermal properties of hyperthermia in a short time. The photothermal conversion efficiency and stability of the xGd-WO 3 @PEG (x = 7 %) were further investigated. Subsequently, the near-infrared thermal and CT imaging performance was studied. The in vitro cell viability on LO2 normal and 4T1 cancer cells have also been conducted. The results showed the xGd-WO 3 @PEG nanomaterials have excellent potential in imaging-guided photothermal cancer therapy. PEGylated xGd-WO 3 nanocrystals with near-infrared plasmon resonance and defective structures were prepared by one step solvothermal method. The samples demonstrated excellent NIR thermal/CT imaging performance and high killing effect on cancer cell. Such visual TMO photothermal agents have potential application for bio-imaging guided cancer therapy. [Display omitted] [ABSTRACT FROM AUTHOR]

Tricobalt tetraoxide (Co 3 O 4) nanoparticles have excellent applications in the fields of electricity, photocatalysis, and ceramics, whereas conventional synthesis methods require sophisticated equipment, strictly controlled conditions, and long duration. Herein, a new method for the synthesis of Co 3 O 4 nanoparticles was proposed. In this emulsion detonation method, the precursor cobalt nitrate hexahydrate (Co(NO 3) 2 ·6H 2 O) was added during the production of the explosives and was therefore more uniformly dispersed than in other detonation methods. The preparation and detonation durations of the explosives were on the scale of minutes and microseconds, respectively, which are much shorter than those in other nanomaterial synthesis methods. The collected products were briefly purified and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectrometer, field emission scanning electron microscopy, and field emission transmission electron microscopy. Cyclic voltammetry and galvanostatic charge–discharge measurements were performed. The results show that the synthesized products were of high purity and consisted mainly of sphere-like particles with a dimensional distribution of approximately 50 nm. The electrochemical properties of these Co 3 O 4 nanoparticles were similar to those synthesized by conventional methods. Combined with the detonation theory and the initial composition of the products, the analysis showed that the synthesis mechanism is mainly divided into two stages: formation and polymerization. Therefore, this approach could provide a new and effective synthesis method for the low-cost production of Co 3 O 4 nanoparticles. [ABSTRACT FROM AUTHOR]

To explore the optimal method for simulating impact welding, we compared detailedly the smoothed particle hydrodynamics (SPH) and structured arbitrary Lagrangian-Eulerian (S-ALE) methods in predicting bonding interface. Based on the experimental results of Cu-Q235 steel atmospheric explosive welding, an in-depth analysis was presented. The results show that the SPH and S-ALE methods converged at element sizes of 2.5 and 2 μm, respectively. When the element size was further reduced to 0.5 % of the wavelength, the errors of both methods were less than 5 %. Benefiting from the gradient mesh, the efficiency of the S-ALE method was 2–4 times that of the SPH method at the same element size. With the addition of the gas medium, the S-ALE method derived the formation mechanism of the gap gas shockwave and indicated that the pressure distribution is not uniform. Furthermore, the local high pressure of the gas shockwave prevents the vortex closure during the wave formation, generating the pore. The calculated pressure and velocity of the wavefront were 20 MPa and 3500 m s−1, respectively. In conclusion, the SPH is suitable for fast previewing waveform interfaces, while the S-ALE method has the advantage of capturing fine waveform structures under various environmental conditions. [Display omitted] • Independent analyses of the impact welding process was carried out by the SPH and S-ALE methods. • The SPH and S-ALE methods revealed different reasons for describing the initial disturbance. • The two methods present their own advantages in facing different problems. • The S-ALE method can capture some defects generated by explosive welding in the atmosphere. [ABSTRACT FROM AUTHOR]