Seiji Yokoyama

Influence of amount of oxidizing slag discharged from stainless steelmaking process of electric arc furnace on elution behavior into fresh water

Fundamental study was carried out for provision for acidification of soil due to acid rain. The influence of weight of the additive slag on elution behavior of the slag into water was studied in this study. Elution experiment was carried out on a basis of JIS K 0058-1. Generally, the pH in the aqueous solution increased with an increase in weight of the additive slag. The pH converged to approximately eight. Calcium, magnesium and manganese, which were essential elements for plants, were eluted from the slag irrespective to elution condition. The eluted concentrations of Ca and Mg increased with an increase in weight of the additive slag. Silicon and zinc were also eluted depending on the conditions. Aluminum that was harmful for plants was not eluted from the used slag.

Storage of CO2 in Low Al2O3 EAF Oxidizing Slag by Grinding with Vibration Mill

The investigation of the behavior of CO2 absorption into the low Al2O3 electric arc furnace (EAF) oxidizing slag under wet grinding was investigated in this paper. The slag was wet ground in the vibration ball mill in the presence of CO2 at room temperature. The observation of the CO2 absorption was made with constant pressure method. The CO2 absorption increased steeply in the early stage of grinding. It occurred simultaneously with the grinding and immediately ceased when the grinding was stopped. The CO2 absorption occurred at the interface between the slag and the water which was saturated with CO2. The CO2 absorption increased as the finer particles were formed by the grinding process, and as the interface between slag and water was increased by the vibration process. A large amount of CO2 absorption and high conversion ratio was observed in the oxidizing slag with low Al2O3 in comparison with those of the slag with the high Al2O3 content.

Preparation of fine particles of tin–M (M: silver, bismuth) alloys with ammonia splashing method

Abstract In this study, as a part of a series of fundamental studies on the production of fine metallic particles with the ammonia splashing method, tin–silver or tin–bismuth alloy on a graphite rod was induction-melted in an ammonia gas stream to investigate the production rate of particles, i.e. the rate of the splash, and the characteristics of the particles. Pure silver and bismuth were not splashed by ammonia gas, but pure tin was splashed. The rate of splash of the alloy decreased with increase of the content of the alloying element. According to the Arrhenius equation, the rate of splash increases with the temperature of the molten alloy. The rate of splash also increased with increase in the ammonia gas flow rate. The particles obtained were metallic and spherical. The size of the particles increased with temperature rise and with increasing ammonia gas flow rate. When alloying elements were added to the pure tin, the particle size decreased abruptly.

Solubility of Nitrogen Gas into Molten Copper at Temperature Range of 1,993 K to 2,443 K

Abstract Solubility of nitrogen gas into pure copper at temperature range of 1,993–2,443 K was studied with using a levitation melting apparatus. The solubility which was dissolved content of nitrogen equilibrated with nitrogen gas with a pressure of 101.3 kPa increased with the temperature of molten copper. However, the solubility was approximately 1.5 mass ppm even at 2,443 K. Absorption of nitrogen gas into pure copper obeyed the Sieverts’ law and was expressed as: 12N2gas=N_

Various mortars for anti-fouling purposes in marine environments

{1 \over 2}{{\rm{N}}_2}\left({{\rm{gas}}} \right) = \underline {\rm N}

Mechanical Separation of Metallic Copper from Polymer‐Insulated Copper Wire

Here, the underlined element was expressed as the element dissolved into a molten copper. The relation between this reaction Gibbs energy, ΔrG0

Preparation of graphite dispersed copper composite with intruding graphite particles in copper plate

{\Delta _{\rm{r}}}{G^0}

Electrochemical formation of tin oxide-hydroxide composite films for the application to electrochromic devices

[J], and thermodynamic temperature of the molten copper, T [K], was given as: ΔrG0=61573+48.75T