Hydrogen production from biogas using hot slag

Possibility of hydrogen production from biogas using hot slag has been studied, in which decomposition rate of _CO2${\mathrm{CO}}_2$–_CH4${\mathrm{CH}}_4$ in a packed bed of granulated slag was measured at constant flow-rate and pressure. The molten slag, discharged at high temperature over 1700 K from smelting industries such as steelmaking or municipal waste incineration. It has enough potential for replacing energy required for hydrogen production due to the catalytic steam reforming or carbon decomposition of hydrocarbon. However, heat recovery of hot slag has never been established. Therefore, the objective of this work is to generate hydrogen from methane using heated slag particles as catalyst, in which the effect of temperature on the hydrogen generation was mainly investigated at range from 973 to 1273 K. In the experiments a mixed gas of _CH4${\mathrm{CH}}_4$ and _CO2${\mathrm{CO}}_2$ was continuously introduced into the packed bed of hot slag at constant flow-rate and atmospheric pressure and then the outlet gas was monitored by gas chromatography. The results indicate that slag acted as not only thermal media but also good catalyst, for promoting decomposition. The product gases were mainly hydrogen and carbon monoxide with/without solid carbon deposition on the surface of slag, depending on the reaction temperature. Increasing temperature led to large hydrogen generation with decreasing un-reacted methane in the outlet gas, at when the largest methane conversion was about 96%. The results suggested a new energy-saving process of hydrogen production, in which the waste heat from molten slag can replace the energy required for hydrogen production, reducing carbon dioxide emission.     

The Safety and Anti-Tumor Effects of Ozonated Water in Vivo

Ozonated water is easier to handle than ozone gas. However, there have been no previous reports on the biological effects of ozonated water. We conducted a study on the safety of ozonated water and its anti-tumor effects using a tumor-bearing mouse model and normal controls. Local administration of ozonated water (208 mM) was not associated with any detrimental effects in normal tissues. On the other hand, local administration of ozonated water (20.8, 41.6, 104, or 208 mM) directly into the tumor tissue induced necrosis and inhibited proliferation of tumor cells. There was no significant difference in the number of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick-end labeling (TUNEL)-positive cells following administration of ozonated water. The size of the necrotic areas was dependent on the concentration of ozonated water. These results indicate that ozonated water does not affect normal tissue and damages only the tumor tissue by selectively inducing necrosis. There is a possibility that it exerts through the production of reaction oxygen species (ROS). In addition, the induction of necrosis rather than apoptosis is very useful in tumor immunity. Based on these results, we believe that administration of ozonated water is a safe and potentially simple adjunct or alternative to existing antineoplastic treatments.     

High-Voltage Screening of Unidirectionally Surface-Ground Titania Ceramics

The effects of high-voltage screening were examined for perpendicularly and parallelly surface-ground titania rectangular bars. A screening field at or below which 30% of titania samples break electrically was applied to each group samples. After high-voltage screening, the surviving samples were subjected to mechanical strength measurement and the resultant strength distribution was compared with the original distribution. After screening, Weibull plots of perpendicularly ground samples bent to become convex curves while plots in the high-strength region remained almost the same, indicating that low-strength samples were selectively eliminated by the high-voltage screening. On the other hand, the screening effect on parallelly surface-ground samples was very small.     

Development of a Multiphase Inactivation Model for an Advanced Oxidation Process and Uncertainty Analysis in Quantitative Microbial Risk Assessment

A multiphase inactivation model of an advanced oxidation process that uses O₃/UV was developed and successfully validated with pilot-scale experiments. Using the inactivation rate constants and dispersion number estimated from the pilot-scale experiments, the inactivation efficacy of O₃/UV under full-scale conditions was predicted. Uncertainty analysis in quantitative microbial risk assessment was performed to examine the impact of the hydraulic conditions of the O₃/UV contactor. It was demonstrated that the estimation of the dispersion number in the full-scale contactor is necessary to improve the accuracy of the risk estimates.     

Quantifying wind‐driven firebrand production from roofing assembly combustion

Large outdoor fires present a risk to the built environment. Examples often in the international media reports are wildfires that spread into communities, referred to as wildland‐urban interface (WUI) fires. Other examples are large urban fires including those that have occurred after earthquakes. Firebrands are a key mechanism on how rapidly fires spread in urban fires and WUI fires. An experimental protocol has been developed to ignite full‐scale roofing assemblies and quantify the degree of firebrand production during the combustion process. As wind is an important factor in firebrand generation, the experiments were conducted under a range of wind speeds at the Building Research Institute's Fire Research Wind Tunnel Facility. A further unique aspect of this work is that the experimental results are compared to firebrand size and mass distributions collected from an actual large‐scale urban fire in Japan. Results of these experiments demonstrate that when only oriented strand board is applied as sheathing, a significant number of firebrands collected from roofing assemblies were less than 1 g and 10 cm². It was also observed that experiments on individual building component firebrand generation provided useful insights into actual urban fire firebrand generation.     

A development of an equilibrium analysis model between electricity retailers under competitive environment

This paper provides a novel equilibrium model for analyzing behaviors of the electric retailers under competitive environment. In the deregulated electricity retail market, the retailers purchase the electricity power and sell it to consumers at the competitive prices. According to their risk attitudes, the retailers optimize the selling prices and the purchase allocation between a day‐ahead market and forward contracts. Without the regulation, an equilibrium by those selfish decision‐making processes of multiple retailers would cause an adverse impact on the electricity market and also the power system. From stable and economical viewpoints, it is important to analyze the unfavorable equilibrium. The selfish behaviors of retailers are modeled as an equilibrium problem with equilibrium constraints in this paper and formulated as a mixed integer linear programming problem to obtain a generalized Nash equilibrium by commercial solvers efficiently. Through computational examples, the proposed model and formulation are validated.     

Development of optimization model for power system operation,outline of model design and verification of output

Osaka Gas Co., Ltd., jointly with NTT DATA Mathematical Systems Inc., has developed unit‐commitment model for optimizing dispatch of power generation units. Main purpose of this development is to simulate the future world of electric power system in accordance with national energy policy aiming to introduce large amount of renewable energy as well as vitalized cross‐border power exchange via PX market to enhance economically‐efficient power system operation. The model incorporates not only constraints of supply‐demand balance but also constraints of operating reserves, regulation reserves, maximum CO2‐emissions, etc.     

Synthesis of Poly(alcohol)s by Hydroboration/Oxidation of Poly(methylallene) Prepared by π-Allylnickel-Catalyzed Living Coordination Polymerization

Summary The π-allylnickel-catalyzed living coordination polymerization of methylallene gave polymers with predictable molecular weight and narrow molecular weight distribution in high yields. The polymers possessing various microstructural units (i.e., the ratio of the 1,2- and the 2,3-polymerizations), produced by varying the nature of the catalyst and the solvents, were subjected to the hydroboration with borane reagents such as borane tetrahydrofuran complex (BH₃•THF) and 9-borabicyclo[3.3.1]nonane (9-BBN). Subsequent oxidation gave poly(alcohol)s whose hydroxy-content could be varied by the borane reagents used. For example, the quantitative conversion of the double bonds in poly(methylallene) into the hydroxy group was attained by the hydroboration using an excess amount of BH₃•THF. Thermal properties of poly(alcohol)s were found to be dependent upon the microstructure and the hydroxy-content of the polymers.     

Direct synthesis of syndiotactic-rich poly(N-isopropylacrylamide) via radical polymerization of hydrogen-bond-complexed monomer

Radical polymerization of N-isopropylacrylamide (NIPAAm) in toluene was investigated in the presence of hexamethylphosphoramide (HMPA). We succeeded in directly preparing syndiotactic-rich poly(NIPAAm), the syndiotacticity of which (r=70%) is the highest among those of radically-prepared poly(NIPAAm)s so far reported, by lowering polymerization temperature to −60 °C in the presence of a two-fold amount of HMPA. The NMR analysis revealed that the induced syndiotactic-specificity was ascribed to 1:1 complex formation between NIPAAm and HMPA. Furthermore, thermodynamic analysis described that the induced syndiotactic-specificity was enthalpically achieved.     

Heterotactic poly(N-isopropylacrylamide) prepared via radical polymerization in the presence of fluorinated alcohols

Radical polymerization of N-isopropylacrylamide in toluene at −40 °C in the presence of fourfold amounts of fluorinated alcohols was investigated. The ¹³C NMR analysis of the obtained polymers suggested that the addition of fluorinated alcohols induced heterotactic specificity in radical polymerization of NIPAAm, although syndiotactic poly(NIPAAm)s were obtained by adding alkyl alcohols as we have previously reported. To the best of our knowledge, this is the first synthesis of heterotactic poly(NIPAAm).