Effect of heating time on structural,morphology,optical,and photocatalytic properties of g-C3N4 nanosheets

Effect of heating time on the structural,morphology,optical,and photocatalytic properties of graphitic carbon nitride(g-C3N4)nanosheets prepared at 550℃in Ar atmosphere is studied.The investigations are carried out by using x-ray diffraction(XRD),scanning electron microscopy(SEM),Fourier-transform infrared spectroscopy(FTIR),UV-vis absorption,and photoluminescence(PL).At a heating temperature of 550℃,g-C3N4 nanocrystals are formed after 0.5 h and become more orderly as the heating time increases.The surface area of the g-C3N4 nanosheets significantly increases as the preparation time increases.The g-C3N4 prepared in 2.5 h shows the highest photocatalytic performance,decomposing completely 10 ppm RhB solution under xenon lamp irradiation for 2.0 h.

Study of Frequency Effects on Hardness Profile of Spline Shaft Heat-Treated by Induction

This paper is devoted to the study of frequency effects on hardness profile of AISI 4340 spline shaft heat-treated by induction through an extensive 3D finite element method simulation and structured experimental investigation. Based on coupled electromagnetic and thermal fields analysis, the 3D model is used to estimate the temperature distribution and the hardness profile. The proposed study examines the hardening process parameters, such as frequency, induced current density and heating time, known to have an influence on hardened surface and builds the simulation model step by step. The established model can provide not only an accurate prediction of temperature distribution and hardness profile but also a comprehensive analysis of machine parameters effects, especially the frequency. The numerical results achieved by this model are good and present a great agreement to the experimental data.

Discussion on design for alkaline cleaning system of continual annealing line

Conventional process flow and main work mechanism of alkaline cleaning process of Continual Annealing Line are generally reviewed in the paper,and the work flow of design is analysed including the lye,rinse water circuit,conductivity detection circuit,utility media supply circuit and other main working circuits.Meanwhile,the heat demand of the alkaline cleaning system,rinse water system and dryer device are also analysed.Lumped parameter method in the heat-transfer theory is adopted to calculate the heating time of unsteady heat transfer for strips in the on-line tank.And the reasons why brush roller is of inverse brush and rinsing nozzles are equipped at the inlet side are found.Types and working principles of iron removal and degreasing devices for alkaline cleaning system,which adopt new magnetic filtration and ultra filtration processes,are described.Besides,the bypass filtering method is used to calculate the processing capacity of magnetic filtration and ultra filtration devices.Finally,the related features of 3-Dimension software 'PlantSpace' for designing a CAL in Baosteel are totally introduced,such as specification for piping,co-designing,pipe code and 3-Dimension design process.