Xuejun Xie

Research on the Relation between Transformer Oil Flow Electrification and Electrostatic Current

In order to study and obtain the mathematical relation between the electrification degree of transformer oil flow and the electrostatic current, a small amount of data about the electrification degree of oil flow and the corresponding electrostatic current is studied by linear regression method and grey model method. The results show that the linear correlation between the electrification degree and the electrostatic current was not good, and the relation between the electrification degree of oil flow and electrostatic current (i) could be expressed as ρ (0) =0.2049 i (0) +169.4419 according to grey model GM (0, 2) when the electrification degree of oil flow is represented by the charge number generated from transformer oil per unit volume, namely the charge density (ρ).

Effect of sulphide in water on corrosion of copper alloys

Purpose – This paper aims to study the corrosion behaviour of copper alloys HSn70‐1 + As and B30 in water with sulphide.Design/methodology/approach – The mass‐loss method, electrochemical tests and surface analysis were used to study the corrosion behaviour of copper alloys HSn70‐1 + As and B30 in water with sulphide.Findings – Dezincification corrosion occurred on HSn70‐1 + As both in water with or without sulphide, and sulphide in water accelerated corrosion, while for the copper alloy B30, the corrosion rates were very small both in water with or without sulphide, although corrosion was also accelerated by sulphide in water.Practical implications – In order to prevent copper alloys HSn70‐1 + As and B30 in water with sulphide from corroding, S2− must be removed.Originality/value – It was found that sulphide in water accelerated the corrosion of copper alloys HSn70‐1 + As and B30 in this paper. Therefore, when water containing sulphide is used as the source of make‐up water and cooling water, S2− in wate...

A study of corrosion inhibition of carbon steel in hydrochloric acid by some benzene nitriles using the quantum chemistry calculation

Purpose – The purpose of this paper is to present a study of corrosion inhibition of carbon steel in hydrochloric acid by some benzene nitriles using the quantum chemistry calculation.Design/methodology/approach – The molecular structure and inhibition mechanism, and the relationship between inhibition efficiency of some benzene nitriles on carbon steel in the hydrochloric acid, were studied from a microcosmic viewpoint using the quantum chemistry calculation.Findings – The calculation results showed that the inhibition efficiency of benzene nitriles on carbon steel in hydrochloric acid could be expressed by σN and ELUMO, and the greater σN absolute value and the lesser the value of ELUMO, then the greater the efficiency of the inhibitor. The regression equation for benzene nitriles is: η=2.665056−0.4447122ELUMO−10.92817σN r=0.9953128.Originality/value – The paper offers insights into the application of the quantum chemistry calculation.

Study on the Killing Effect of Sodium Hypochlorite and Benzalkonium Bromide and the Compatibility of Them with the Scale and Corrosion Inhibitor

The killing effect of sodium hypochlorite and benzalkonium bromide and the compatibility of them with the scale and corrosion inhibitor in the seawater is studied in the paper. The research result shows that sodium hypochlorite and benzalkonium bromide have good killing effect, sodium hypochlorite or benzalkonium bromide is not only compatible with a scale inhibitor, also compatible with a corrosion inhibitor formulation. Introduction One of the most effective and common method to control microorganism growth in the cooling water system is to add killing agent into the cooling water. From the investigated market situation, there are many kinds of biocides, most of them are used in the freshwater cooling system, and fewer is aiming at the complex seawater cooling system. Because there are many types of marine organisms in seawater, the higher requirement for the biocide performance is put forward. With the improvement of environmental protection consciousness, the traditional efficient biocide is gradually restricted to be used. In order to balance the environmental protection, economic benefits and the killing effect, the killing method to combine the traditional biocide chlorine with the non oxidizing biocide, such as to combine sodium hypochlorite with quaternary ammonium salt, is chosen. [1-13]

Study on the Alkalization Treatment of the Turbo-Generator's Inner Cooling Water

The applied technical condition and the water quality of two alkalization treatments, which are adding alkaline chemicals and sodium ion exchange treatment, are studied by tests. It is a good way to use alkalization treatment to promote the quality of turbo-generator inner cooling water and prevent the hollow copper lead from corrosion, and to assure safe and economical operation of turbo-generator.