The production was carried out by the agitation of dispersed waste aluminum fine powders in . A magnetic stirrer was used for agitation of the mixtur in a triangle flask. The waste fine powders from the arc spraying and the plasma spraying were used as aluminum source. In the experiment, reaction temperature, number of revolutions and the size and shape of magnetic stirrer bars were changed. The shape of the waste aluminum fine powders was observed by a scanning electron microscope. Crystal structure was investigated by powdery X-ray diffraction. As a result, the amount of production changed by different waste aluminum fine powders at the same agitation condition. It was found that the powder after the reaction with the formed larger size aggregates and generated a lot of aluminum hydroxide. In addition, agitation speed and the size of magnetic stirrer bars had a large influence on the production of .

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A powerful new simulation procedure is developed for the multistage / exchange column for heavy enrichment. In comparison with the distillation column, the exchange column considered here has several specific features such as the presence of three streams (liquid , vapor and gas), occurrence of isotopic exchange reactions and much more complex column configuration comprising two different kinds of stages, a catalytic oxidizer at the top and an electrolytic cell at the bottom. The main calculational loop proposed here is the Newton-Raphson method where the number of independent variables is just equal to the total number of /vapor scrubbing stages. Unlike the previously reported procedures for the exchange column, the present procedure is applicable even in cases where the deuterium concentration is significantly high, varying greatly from stage to stage within the column.

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The feasibility of using hot spring

for production via hydrothermal reaction with aluminum was evaluated by performing experiments at Zao and Tamagawa hot springs in Northeast Japan. The results of the study demonstrate the viability of the proposed method for advanced direct geothermal energy use. The amount of produced using Tamagawa hot spring (pH 0.88, 50 °C) was higher than that produced using Zao hot spring (pH 1.60, 50 °C). Moreover, numerical simulation of the Al–H₂O reaction at various temperature and pH conditions produced results consistent with experiments for both Zao and Tamagawa hot springs. The results of experiments and simulation indicated that pH is more significant than that of temperature for determining the amount of generation.

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  The removal rate of radioactive materials from contaminated was experimentally obtained using various materials and commercial purifiers with the aim of enabling the public to easily remove radioactive materials from rainwater and tap contaminated by radioactive ¹³¹I, ¹³⁴Cs, and ¹³⁷Cs released by the Fukushima Daiichi Nuclear Power Plant accident using readily obtainable instruments and materials at home. Since it was difficult to obtain contaminated tap , contaminated rainwater was used as samples in our experiments. In the rainwater, ¹³¹I, ¹³²I, ¹³⁴Cs, ¹³⁷Cs, ¹³²Te, ^129mTe, and ¹²⁹Te were detected. The abundance ratio of the isotopes depended on the location and date of collection, and the abundance of ¹³¹I was 12 to 26 times higher than that of ¹³⁷Cs. Most of the radioactivity in the rainwater originated from ¹³¹I. The removal rate was obtained in the case of using readily available materials and purifiers at home and in a university laboratory. The results of model experiments using nonradioactive I₃^- and radioactive ¹²⁵I instead of ¹³¹I suggested that activated carbon was effective. On the basis of these results, we investigated the removal rates of radioactive iodine and cesium using five different pot-type purifiers with activated carbon as the basic adsorbent, to which ion-exchange resin, a hollow fiber membrane, or a ceramic was added. Approximately 90 to 99% of ¹³¹I and 94 to 100% of ¹³⁷Cs were removed by consecutive purifications using the pot-type purifiers. These results indicated that these purifiers can be easily used to remove ¹³¹I and ¹³⁷Cs at home, although special care is required when boiling using an electric kettle because it causes the concentration of ¹³¹I. Faucet-mounted- and countertop-type purifiers with activated carbon as the basic material are expected to have a similar performance to pot-type purifiers, although this requires future experimental verification. We found that 1-9% of the radioactive ¹³¹I remained in the rainwater samples after repeated treatment with the pot-type commercial purifiers, depending on the sampling location and time, and that some of the residual isotopes were adsorbed on silica nanoparticles. Furthermore, to improve the removal rate, it is necessary to develop a removal method for the remaining components.

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The D/H fractionation factors between the crystal of copper chloride dihydrate and a saturated aqueous solution of copper(II) chloride, α_CW-st.sol, and between the saturated aqueous solution and vapor, α_st.sol-V, were experimentally determined at 25°C in equilibrium. The observed values of α_CW-st.sol and α_st.sol-V, were 0.950 ± 0.002 and 1.052 ± 0.001, respectively. The D/H fractionation factor between the crystal of copper chloride dehydrate and vapor in equilibrium, α_CW-V, was calculated to be 0.999 ± 0.002 from the observed values of α_CW-st.sol and α_st.sol-V, and is used to discuss D/H fractionation in crystal of crystalline hydrates. It is shown that such D/H fractionation is better expressed by α_CW-V than by the conventionally used fractionation factor between crystal and mother liquor, α_CW-st.sol, because α_CW-V represents the activity ratio, whereas α_CW-st.sol is simply the concentration ratio. Based on the results in this study, we consider that the coordination bond between divalent cupreous ions and oxygen atoms in molecules and the bond between crystal and chlorine ions contribute substantially to the fractionation of isotopes.

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In 2007, the first report that

removes active oxygen was published, and many clinical and non-clinical studies have since been conducted using gas and . Dietary supplements are used by a large number of patients as self-medication. Although dietary supplements cannot be considered as drugs, patients expect pharmacological benefits from them since they usually have very little knowledge of their effects. Thus, pharmacists have the responsibility to expand their knowledge of dietary supplements so that they can give better advice to patients who are using them.

This study examined the effect of temperature on the dissolved H₂ concentration in

and clarified the difference in changes in H₂ concentration among commercial products. We compared 5 commercial products packed in aluminum pouches (Product A, Product B, Product C), aluminum cans (Product D) or plastic bottles (Product E), and measured the dissolved H₂ concentration for up to 120 days when stored at 26℃ and 37℃ using a needle-type H₂ sensor. We found that the H₂ dissolved in Product A was stable for 120 days at 26℃ and 37℃. Product B and C maintained high H₂ concentrations at 26℃, but the H₂ concentration gradually decreased at 37℃. The H₂ concentrations of products D and E were low and undetectable, respectively. Our experiments suggest that all products packed in aluminum pouches, aluminum cans or plastic bottles stored during distribution at 26℃ and 37℃ may be influenced by the time course of changes in the concentration of .

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The reaction of aluminum with

is of great interest to production. However, it is very difficult to initiate the reaction owing to the oxide film covering the aluminum powder surface, especially for the reaction of micrometer-aluminum powder with . Na₂CO₃ was invoked as a modifier to improve the yield of the reaction of micrometer-aluminum with at low temperatures. The effects of solution concentration and temperature on the yield were studied. The results indicate that the yield of the reaction of micrometer-aluminum powder with without the addition of Na₂CO₃ is low owing to the low activity of micrometer-aluminum powder. Increasing the temperature, the yield increases slightly. However, when Na₂CO₃ is added into the mixture of micrometer-aluminum powder and , the yield is significantly improved owing to the production of OH⁻ of Na₂CO₃ hydrolysis to destroy the oxide film on the micrometer-aluminum powder surface. The yield of micrometer-aluminum powder and with the addition of 3 wt% Na₂CO₃ reaches 89.90% at 70°C. There are two stages in the reaction process of micrometer-aluminum powder and with the addition of Na₂CO_3: the fast reaction stage and slow reaction stage. The reaction activation energy of micrometer-aluminum powder with increases with the increase of Na₂CO₃ concentration. Based on these results, the reaction mechanism is discussed.

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We studied the production from four kinds of wet food wastes using high pressure superheated steam, which is reactive above the critical temperature and below the critical pressure of . 1.8–2.0 mmoles of gas were produced from 1 mmole of organic carbon in the wastes at 700°C, 10 MPa, 30 min, 20 of the molar ratio of to organic carbon and 20 wt% of the potassium hydroxide to the organic content in the waste. The production of gas was accelerated by increasing the temperature and molar ratio of to organic carbon in the waste, but suppressed by increasing the pressure. On the other hand, the production of ammonia, which is a typical by-product of gasification of food wastes, reduced by increasing the temperature and decreasing the pressure. Judging from the experimental results, high pressure superheated steam with low pressure was more effective than supercritical with high pressure. The calculated equilibrium mole fractions of gas based on the ideal gas assumption agreed with the experimental data in wide temperature and pressure regions, but those of methane and carbon dioxide deviated from the data above 600°C.

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Using in high temperature and pressure, we produced gas from cross-linked polyethylene (XLPE) efficiently. Around two moles of gas were produced from a mole of carbon in XLPE at the optimum conditions of 700°C, 30 min, 20 of molar ratio of to carbon in XLPE and 20 wt% nickel catalyst. This fact showed that gas exceeding in XLPE was produced by the reaction of plastic and at high temperature and pressure. The production was accelerated by increasing the temperature and molar ratio of to carbon in XLPE, but suppressed by increasing the pressure. Nickel and alkali catalysts gave excellent performance on the gas productivity from XLPE. Both catalysts promoted the degradation of plastic and –gas shift reaction but did not affect the methanation much. The order of the catalytic activity was nickel > potassium hydroxide > sodium hydroxide. The equilibrium gas-phase composition calculated by MALT2 agreed with the experimental results, when XLPE was gasified completely.

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The presence of in embrittled copper was demonstrated by calorimetry and low frequency internal friction measurements. Copper specimens with varying oxygen contents of 90 to 1250 mass ppm were subjected to annealing in atmosphere at temperatures between 300 and 700°C. The differential scanning calorimetry of such specimens exhibited heat absorption associated with the ice- transformation. By changing the lowest temperature where the heating started for the measurement, supercooling of −10 to −35°C was observed. Low frequency internal friction showed a corresponding change; the internal friction is simply interpreted to consist of contributions from the matrix copper and the dispersed ice crystals.

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The purpose of this study is to develop a microcompact fuel-cell vehicle equipped with a generation system. is generated by the reaction between and activated aluminum particles without carbon dioxide emission. The activated aluminum is made of aluminum cutting waste through activation treatments such as compression crushing and freezing dry. One gram of the activated aluminum particles can generate about 1.1 liters of pure . The developed generator is consists of a tank, an electrical pump, a reaction container, a condensate return tank, sensors and a one-chip microcomputer. It generated about 1-4 [l/min] of over one hour. A microcompact vehicle was manufactured experimentally based on a delta trike. The front wheel was driven by a brushless motor of 100 [W]. The developed generator and a fuel-cell of 100 [W] were equipped on the microcompact vehicle. It was confirmed that the vehicle drive at about 11 [km/h] over 90 minutes.

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The purpose of this study is to describe the experiments of generation from molecules reacting with activated aluminum particles and the identification of its characteristics using an ARMA model on the assumption of the applications for a fuel-cell vehicle. Because 1 gram of the activated aluminum particles can generate about 1.1 liters of pure , they have application possibility as the resource of a fuel cell car. However, the details of generation characteristics by this reaction are not well known. The reaction has non-linearity and time-varying due to the characteristics of the sample, the external environment and so on. Therefore, it is difficult to construct a mathematical model based on the physiochemical law of the reaction. Here, the dynamic characteristics of generation are assumed to be described as a linear ARMA model using the reaction temperature and generation. The parameters of ARMA model are identified by a constant trace adaptive algorithm using the measured data. The outputs of the ARMA model are well accorded with the measured data.

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A novel, green method for (H₂) production was studied; the method involves the mechanical mixing of aluminum (Al) with (H₂O). We examined the use of glass and stainless steel reactors. When the glass reactor was used, the induction period of the reaction of Al with H₂O was long. The induction period decreased remarkably upon increasing the revolution rate; the optimal revolution rate was 1250 rpm. Furthermore, the reaction of Al with H₂O in the stainless steel reactor was examined to investigate the practical feasibility of this H₂ production method. In this case too an induction period was observed, and the induction period decreased upon increasing the reaction temperature and Al weight.

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We analyzed the structural differences of H₂O molecules in

nanodroplet on graphene ((H₂O)₉₈ on graphene) model by using the density functional theory. 98 H₂O molecules on graphene were classified into four groups based on the surrounding condition (bulk region, -gas interface, -graphene interface, and -graphene-gas interface). The O–H distances and vibrational frequencies of H₂O molecules near the gas region were wider distributions compared with the H₂O molecules in the bulk region, whereas narrower distributions were obtained near the graphene interface.

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Hardened cement pastes (HCP) with different

contents were irradiated with gamma rays under different temperatures and irradiation dose rates. The relationship between the quantity of gas produced and the content as well as the stability of HCP under gamma irradiation was evaluated. It is experimentally confirmed that gas was mainly produced from the evaporable . The G value of the production assuming the radiation energy absorbed by the total composed of chemically bound (CBW) and evaporable was ranging from 0.03 to 0.42. The G value of the production for CBW was ranging from 0.03 to 0.07, which were an order of magnitude smaller than that of the bulk (0.45).

Assuming that the radiation energy on evaporable

is used for the formation of , it is experimentally confirmed that, in case of low dose rate, the G value tended to converge to a constant value when the evaporable exceeded a certain value, while, in case of high dose rate, the G value increased as evaporable increased. However, the G values of all cases grew with increasing evaporable content and exceeded the G value of the bulk (0.45). The CBW was not susceptible to gamma irradiation. Only 2 to 3% of the CBW was estimated to be decomposed by 200 MGy of gamma irradiation.

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We evaluated the properties and real existence of an electrolyzed-reduced , which we prepared, and three commercially purchased goods, that are advertised to have antioxidant activities by the action of “active ,” on the basis of the results of examinations for inhibitory effects on the oxidative reactions of biomolecules, quantitative analyses of the minerals, and the ESR spectral data in measurement of the scavenging ability for reactive oxygen species. The results suggested that all of the examined aqueous solution systems undoubtedly have antioxidant activities in vitro and that such effects are derived from ordinary molecular ( gas) and/or (a) reductive vanadium ion(s). “Active ” seems to be absent as an effective component of the antioxidant activities of these aqueous solution systems.

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Platinum catalyst loaded tungsten oxide (Pt/WO₃) is a promising candidate as a gas sensor material, which can detect it through optical and electrical sensing. The sensor, which can detect the gas stably in various environments, is strongly demanded. In this study, we prepared the Pt/WO₃ thin film by the sol–gel method and evaluate the dependence of the gas sensing property on measuring temperature and humidity. gas sensing property of Pt/WO₃ thin film was evaluated by measuring the electrical conductivity with humid (0–100% of relative humidity) gas exposure at various temperatures. The sensing property was declined in humid atmospheres because the molecule adsorbing on the film surface disturbed the catalytic reaction between and Pt surface. In addition, the catalytic combustion of molecule on Pt was also disturbed by the adsorbed . However, the heating at 60°C can remove the effect of molecule and the film can detect gas stably. From these results, it was considered that the degradation of sensor response in humid atmosphere was mainly dominated by adsorbing on Pt catalyst surface.

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Cement solidification/stabilization is an effective way of suppressing the leaching of hazardous materials from municipal solid waste incinerator (MSWI) fly ash, though the solidification of the fly ash from fluidized bed incinerators has been difficult because it causes the evolution of

gas by the reaction of contained metallic aluminum and alkaline and results in the formation of porous and brittle solid. We found that the evolution of gas is possible to be suppressed by improving the mixing method of the ingredients and controlling the amount of CaCl₂ in the mixture. Thorough mixing of the fly ash and cement powders with a drum-type mixer and subsequent addition of at once scarcely induces the mechanical destruction of protective oxide layers surrounding metallic aluminum particles during the mixing process, so that the aluminum particles are protected from the attack of alkaline . soluble CaCl₂ externally added and/or contained in the fly ash helps not only the homogeneous penetration of into the powder mixtures but also reduces the alkalinity of , so that it suppresses the evolution of gas.

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