Thermodynamic Study on Sn-Fe Alloys

Thermodynamic properties of molten Sn-Fe alloys were estimated by e.m.f. measurements of the following cell employing solid electrolytes at the temperature range of 900～1250°C Fe, FeO/ZrO₂ (+CaO)/Sn-Fe, FeO From these experimental results it was found that the activities of components in molten Sn-Fe alloys (hard head) were found to show considerable positive deviation from Raoult's law. Based on the activities of components in molten Sn-Fe alloys and the equilibrium experimental results of Davey and Floyd the equilibrium relations between slag and metal in tin smelting were investigated

Preparation of Titanium Tetrachloride : Some Experiments for the Determination of its Mechanism

As one of the fundamental experiments on the preparation of titanium tetrachloride, several chlorinations such as that with and without carbon by chlorine gas, that by the mixed gas of chlorine and carbon monoxide, and that by carbon tetrachloride vapour are examined using titanium dioxide and its lower oxides as the material. By the results, it is known that the ignition temperature generally becomes lower as the titanium content in the oxides increases, but it is exceptional in case of the chlorination by the mixed gas of chlorine and carbon monoxide

Thermodynamic Properties of Wustite (FeO₁₊y)

E.m.f. measurements of the cell, Pt/FeO₁₊y/ZrO₂ (CaO)/Ni-NiO/Pt, have been carried out to investigate the thermodynamic characteristics of wustite (FeO₁₊y). From these results, the relationship between temperature, oxygen pressure and composition of wustite and the phase boundaries of wustite phase in the binary system Fe-O were obtained and compared with those given by Darken and Gurry. The thermodynamic quantities such as activities of iron and oxygen in wustite, partial molar enthalpies and entropies of solution of oxygen in wustite and free energy of formation of magnetite were also evaluated. The defect sturcture of wustite was discussed in relation with the Po₂ dependence of cation vacancy concentration of wustite

Thermodynamic Study on the Systems of Metals and Their Oxides by EMF Measurements Using Solid Electrolyte

Emf of the following galvanic cell employing solid electrolyte were measured at the temperature range of 700°～1100°C. Pt/Ni · NiO/O--/Air/Pt Pt/Ni · NiO/O--/Cu · Cu₂O/Pt Pt/Ni · NiO/O--/Co · CoO/Pt Pt (Fe · FeO/O--/Ni · NiO/Pt Pt/Fe · Fe₁₋ₓO/O--/Fe₁₋yO · Fe₃O₄/Pt Pt/Ni · NiO/O--/Fe₃O₄ · Fe₂O₃/Pt From those results the equilibrium oxygen pressures of Ni·NiO, Cu·Cu₂O, Co·CoO, Fe·FeO, FeO·Fe₃O₄ and Fe₃O₄·Fe₂O₃, and the standard free energy of formation of NiO, Cu₂O, CoO, FeO, FeO·Fe₃O₃ and Fe₂O₃ were estimated. Based on these experimental results it is shown that 1) stabilized zirconia and thoria could be used as a solid electrolyte under the conditions of 700°～1100°C and partial pressure of oxygen between 1 atm. and 10⁻²⁰ atm., and a little impurity in electrolyte did not have an unfavorable effect on the determination of equilibrium partial oxygen pressure of metal-metallic oxide systems 2) alumina and magnesia could not be used as a solid electrolyte of the present emf measurements 3) one might conclude that emf measurements using a solid electrolyte could obtain the same thermodynamic values as the other reliable equilibrium methods

DNA Methylation of Colon Mucosa in Ulcerative Colitis Patients: Correlation with Inflammatory Status

Background: Although DNA methylation of colonic mucosa in ulcerative colitis (UC) has been suggested, the majority of published reports indicate the correlation between methylation of colon mucosa and occurrence of UC-related dysplasia or cancer without considering the mucosal inflammatory status. The aim of this study was to verify whether mucosal inflammation-specific DNA methylation occurs in the colon of UC. Methods: Of 15 gene loci initially screened, six loci (ABCB1, CDH1. ESR1, GDNF, HPP1, and MYOD1) methylated in colon mucosa of UC were analyzed according to inflammatory status using samples from 28 surgically resected UC patients. Results: Four of six regions (CDH1, GDNF, HPP1, and MYOD1) were more highly methylated in the active inflamed mucosa than in the quiescent mucosa in each UC patient (P = 0.003, 0.0002, 0.02, and 0.048, respectively). In addition, when the methylation status of all samples taken from examined patients was stratified according to inflammatory status, methylation of CDHI and GDNF loci was significantly higher in active inflamed mucosa than in quiescent mucosa (P = 0.045 and 0.002, respectively). Multiple linear regression analysis revealed that active inflammation was an independent factor of methylation for CDHI and GDNF. DNA methyltransferase 1 and 3b were highly expressed in colon epithelial cells with active mucosa] inflammation, suggesting their involvement in inflammation-dependent methylation. Conclusions: Methylation in colonic mucosa of UC was correlated with mucosal inflammatory status, suggesting the involvement of methylation due to chronic active inflammation in UC carcinogenesis