Effect of a magnetic field on droplet freezing and frost formation on cold surfaces.

The effect of a magnetic field on condensed droplet freezing and frost formation was investigated using visualized experimental devices in this study. The size, shape, freezing time of droplets, and frost shape on the magnetic field considerably differ from those on the nonmagnetic surface. Moreover, the magnetic field could suppress droplet freezing and frost formation. The magnetic field suppression effect on droplet freezing and frost formation was analyzed according to the polarity characteristics of water molecules.

Highly efficient in vitro biosynthesis of silver nanoparticles using Lysinibacillus sphaericus MR-1 and their characterization.

Silver nanoparticles (AgNPs) have been widely used in diverse fields due to their superior properties. Currently the biosynthesis of AgNPs is in the limelight of modern nanotechnology because of its green properties. However, relatively low yield and inefficiency diminish the prospect of applying these biosynthesized AgNPs. In this work, a rapid mass AgNP biosynthesis method using the cell-free extract of a novel bacterial strain, Lysinibacillus sphaericus MR-1, which has been isolated from a chemical fertilizer plant, is reported. In addition, the optimum synthesis conditions of AgNPs were investigated. The optimum pH, temperature, dosage, and reaction time were 12, 70 °C, 20 mM AgNO3, and 75 min, respectively. Finally, AgNPs were characterized by optical absorption spectroscopy, zeta potential and size distribution analysis, x-ray diffraction, electron microscopy, and energy-dispersive x-ray spectroscopy. The results revealed that these biosynthesized AgNPs were bimolecular covered, stable, well-dispersed face centered cubic (fcc) spherical crystalline particles with diameters in the range 5-20 nm. The advantages of this approach are its simplicity, high efficiency, and eco-friendly and cost-effective features.

Research on the Solid-Liquid Composite Casting Process of Incoloy825/P110 Steel Composite Pipe.

Bimetallic composites have a wide range of application prospects in various industries. Different bonding temperatures, as one of the influencing factors, directly affect the bonding effectiveness as well as the performance and application of the materials. Using metallurgical bonding techniques ensures a strong bond at the interface of bimetallic materials, resulting in high-quality composite pipe billets. This paper describes an Incoloy825/P110 steel bimetal composite material made by the solid-liquid composite method. By utilizing ProCAST 14.5 software for simulation and deriving theoretical formulas, an initial range of temperatures for bimetallic preparation has been tentatively determined. And this temperature range will be utilized for on-site experiments to prepare bimetallic samples. After the preparation process is completed, samples will be selected. The influence of the external mold temperature on the interface bonding of Incoloy825/P110 steel solid-liquid composite material is studied using an ultra-depth three-dimensional morphology microscope and a scanning electron microscope. Through research, the optimal preheating temperature range for the solid-liquid composite outer mold of Incoloy825/P110 bimetallic composite material has been determined. The casting temperature of the inner mold has a significant impact on the interface bonding of this bimetal composite material. As the casting temperature of the inner mold increases, the interface thickness gradually increases. At lower temperatures, the interface thickness is lower and the bonding is poorer. At higher temperatures, melting may occur, leading to coarse grains at the interface. When the temperatures of the inner and outer molds are within a certain range, a new phase appears at the interface. Indeed, it increases the strength of the interface bonding. Due to co-melting of the bimetal near the interface, element migration occurs, resulting in increased Ni and Cr content at the interface and enhanced corrosion resistance.

Biosynthesis and characterisation of silver nanoparticles using Sphingomonas paucimobilis sp. BDS1.

Sphingomonas is a novel and abundant microbial resource for biodegradation of aromatic compounds. It has great potential in environment protection and industrial production. The use of microorganisms for the synthesis of nanoparticles is in the limelight of modern nanotechnology, since it is cost effective, non-toxic and friendly to the ever-overwhelmed environment. In this paper, the biosynthesis of silver nanoparticles (AgNPs) using Sphingomonas paucimobilis sp. BDS1 under ambient conditions was investigated for the first time. Biosynthesised AgNPs were characterised with powder ultraviolet-visible spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy and energy dispersive X-ray spectroscopy. The overall results revealed that well-dispersed face centred cubic spherical AgNPs in the range of 50-80 nm were produced on the surface of Sphingomonas paucimobilis sp. BDS1, after challenging pure wet biomass with silver nitrate solution. This suggests that the capture of silver ions may be a complex process of physical and chemical adsorption and the proteins on the surface of the bacteria may play the role of reduction and stabilising agent with regard to the result of FTIR.