Tetsuya Nagasaka

The Waste Input‐Output Approach to Materials Flow Analysis

Abstract: A general analytical model of materials flow analysis (MFA) incorporating physical waste input‐output is proposed that is fully consistent with the mass balance principle. Exploiting the triangular nature of the matrix of input coefficients, which is obtained by rearranging the ordering of sectors according to degrees of fabrication, the material composition matrix is derived, which gives the material composition of products. A formal mathematical definition of materials (or the objects, the flow of which is to be accounted for by MFA) is also introduced, which excludes the occurrence of double accounting in economy‐wide MFAs involving diverse inputs. By using the model, monetary input‐output (IO) tables can easily be converted into a physical material flow account (or physical input‐output tables [PIOT]) of an arbitrary number of materials, and the material composition of a product can be decomposed into its input origin. The first point represents substantial saving in the otherwise prohibitive cost that is associated with independent compilation of PIOT. The proposed methodology is applied to Japanese IO data for the flow of 11 base metals and their scrap (available as e‐supplement on the JIE Web site).

Kinetics of the reaction of H2O gas with liquid iron

AbstractThe rate of the decarburization of carbon-saturated liquid iron by H20 gas between 1673 and 1873 K has been studied under conditions in which the effect of mass transfer is negligible, or a reasonable correction for its effect can be made. The rate was measured for water vapor pressures in the range 0.002 to 0.3 atm and sulfur contents in the metal from 0.005 to 0.5 mass of H20 on the surface. Sulfur was found to significantly decrease the rate, and the residual rate phenomenon was observed at high sulfur content. The rate constant for the dissociation of H20 on liquid iron is given byn

Rate of Nitrogen Desorption from Liquid Iron- Carbon and Iron-Chromium Alloys with Argon

k = frac{{k^circ }}{{1 + K_s a_s }} + k_r

Kinetics of the reaction of CH4 gas with liquid iron

nn wherek°,kr,Ks, andas are the rate constant for pure iron, residual rate constant, the adsorption coefficient of sulfur, and the activity of sulfur in the metal relative to 1 mass pct in carbonsaturated liquid iron, respectively. The rate constants and adsorption coefficient were determined to ben

Surface Roughness of Solidified Mold Flux in Continuous Casting Process

begin{gathered} log k^circ = frac{{ - 4860}}{T} + 0.57 (mol/cm^2 s atm) hfill log k_r = frac{{ - 5350}}{T} - 1.03 (mol/cm^2 s atm) hfill log K_S = frac{{3870}}{T} + 0.51 hfill end{gathered}

Dissolution behavior of nutrition elements from steelmaking slag into seawater

n