Densities of six binary, three ternary and quaternary mixtures formed by water, methanol, ethanol, and 1-propanol have been measured at 298.15, 308.15, 318.15, 328.15 and 338.15 K. The binary parameters of an NRTL-type equation for excess molar volumes were determined from the binary density data. The calculation of ternary and quaternary excess molar volumes with the binary parameters shows that the proposed method successfully estimates the excess molar volumes over the entire composition and temperature ranges with a reasonable accuracy.
A statistical-mechanical analytical equation of state has been employed successfully to molten alkaline earth metals. The temperature-dependent parameters of the equation of state have been calculated using our previously reported corresponding-states correlation based on the normal boiling point parameters as the scaling constants. It is shown that knowledge of just normal boiling temperature and the liquid density at a normal boiling point are sufficient to predict the equation of state of magnesium, calcium, stroncium, and barium from the melting points up to several hundred degrees above their boiling points. A comparison of calculated saturated liquid densities of these metals with experimental ones shows that our predicted results are within a 5% difference of experimental ones.
A mesh-type Cu-Mn-CeOx/Al2O3/Al alumite catalyst was employed to investigate the selective reduction of NO with C3H6 in the presence of SO2 and H2O. The effect of SO2 on the de-NOx activity closely depended on SO2 concentration and temperature. At a low temperature (673 K), SO2 of 50 ppm greatly improved the NOx reduction, but a further increase in SO2 concentration (up to 500 ppm) caused a rapid catalyst deactivation. As temperature increased to 723 K, the catalyst deactivation caused by 500 ppm SO2 disappeared, and further the presence of SO2 also produced a remarkable promotion in the de-NOx activity. The effect of SO2 was observed to be an irreversible course associated with irreversible chemical phase transition. The presence of SO2 was considered to inhibit the over-oxidation of the organic-intermediates by oxygen, and to make the organic-intermediates more available for the NOx reduction. However, a high concentration of SO2 inhibited not only this over-oxidation but also propene activation, and led to catalyst deactivation. The inhibition of SO2 in the propene activation, mainly attributed to the over-adsorption of SO2, could be weakened as temperature increases. Although the presence of water vapor depressed the de-NOx activity, this change was almost reversible. In comparison with the separate presence of SO2, the coexistence of H2O and SO2 more dramatically improved the NOx reduction. It was considered possible that the coexisting H2O diluted SO2 to lessen the inhibition effect of SO2 on activating propene.
Methylamine (MA) and dimethylamine (DMA) were examined as catalysts for the hydrolysis of tetraethyl orthosilicate (TEOS) to synthesize monodispersed silica particles. Experimental results were compared with those in ammonia-catalyzed hydrolysis of TEOS. The hydrolysis reactions were carried out at a water concentration of 11 kmol/m3 in ranges of catalyst concentration (0.01–1.5 kmol/m3) and TEOS concentration (0.02–0.2 kmol/m3). Spherical particles were formed at catalyst concentrations lower than 1.5 kmol/m3 for NH3 and lower than 0.2 kmol/m3 for MA and DMA. Comparison of the coefficient of variation (CV) for monodisperse spherical particles indicated that silica particles obtained with the amine catalysts were more highly monodisperse than those obtained with NH3 catalyst.
Sub-micron sized hollow spheres were fabricated starting from core-shell particles. Polystyrene particles with a size of 345 nm were coated with a titania shell of 15 nm thickness by a sol-gel method. The core-shell particles prepared were annealed at 500°C in air to remove the polystyrene core and crystallize the titania shell. The crystal structure of the hollow titania shell was anatase and its surface area was 91.0 m2/g.
Ultrafiltration behavior of Corynebacterium glutamicum (C. glutamicum) slurry was investigated with and without bovine serum albumin (BSA). It was found that the average specific filtration resistance αav of C. glutamicum slurry depended on slurry pH without BSA: αav was much lower in the pH from 2.0 to 4.0 than in the pH from 4.5 to 8.0. The measurement of particle size distribution and zeta potential of cells indicated that the area mean diameter and the surface charge of cells were maximum and minimum at pH 3.0, respectively. Such a change in the state of aggregation due to the decrease of surface charge reduced αav. Furthermore the effect of the mass fraction sb of BSA on αav was investigated under a constant total mass fraction s of BSA and cells at pH 4.5, where cells and BSA were oppositely charged. The addition of a small amount of BSA was effective below 0.08 of sb/s for reducing αav via aggregation of cells where BSA worked as a binder between cells. Over 0.08 of sb/s, however, αav increased due to the increase of free BSA of which αav was much higher than that of cells. The interaction manner of BSA and cells was found mono-layer adsorption of BSA to cells, following the Langmuir isotherm, according to the measurement of the adsorption amount of BSA to cells.
Activated carbons were prepared from LFG (wastes generated during Lactic acid Fermentation of kitchen Garbage). Activated carbons were prepared by conventional steam activation and via the acid treatment prior to the steam activation. Porous properties of the prepared activated carbons were evaluated from nitrogen adsorption isotherms at 77 K. Activated carbons prepared by steam activation from LFG had much more mesopores than a commercial activated carbon, and had unique broad-shaped pore size distributions. It was evident from the ultimate analysis at each preparation stage of the carbons that the activated carbons prepared from LFG contain much nitrogen as carbonaceous materials. It was found that the burnoff of nitrogen during steam activation of LFG contributes to the formation of unique pore size distributions of the activated carbons. Activated carbons prepared via the acid treatment had not only more mesopores but also more micropores than the commercial activated carbon. It was suggested that LFG was useful as a resource for practical activated carbons, especially, for mesoporous activated carbons. It was also beneficial to apply the acid treatment to improve the porous properties of the prepared activated carbons.
The temperature decrement in the inner parts of porous materials immersed in a gas-solid fluidized bed was observed in drying. To clarify the mechanism of this phenomenon, a theoretical calculation includes heat and mass transfers in a porous material (sample) was performed, and the heat balance in the sample was estimated. The effects of temperature of drying gas and the thermal conductivity of the sample on the temperature decrement were also examined. In the case of fluidized bed drying, the amount of heat flow in a sample is very large at the earlier period of drying (surface evaporation period). After the sample surface dried, the amount of heat flow in the inner parts of the sample is governed by the thermal conductivity of the sample. During the period, the amount of heat consumption for evaporation increases and it becomes larger than that of heat conduction in the inner parts of the sample in drying. This inversion is the reason of the temperature decrement in the inner parts of the sample in fluidized bed drying. The decrement degree of temperature becomes larger as the temperature of drying gas increases. The temperature decrement occurs more easily as the thermal conductivity becomes lower.
In order to obtain the fundamental information required to prepare microcapsules by interfacial polycondensation polymerization, oil-in-water emulsions were prepared by dispersing limonene oil in the aqueous solution of poly(vinyl alcohol) (PVA) with different degrees of polymerization and saponification. Emulsion prepared was characterized by measuring the droplet diameters and the physical properties of emulsion. Emulsion stability was estimated by measuring the transient height of the oil phase layer and the interfacial excess concentration for each PVA. PVA with higher surface activity showed smaller occupied interfacial area due to the larger excess concentration and resulted in stabilized emulsion.
A multi-product, multi-stage, and multi-period production and distribution planning model is proposed in this paper to tackle the compromised sales prices and the total profit problem of a multi-echelon supply chain network with uncertain sales prices. This model is constructed as a mixed-integer nonlinear programming problem to achieve a maximum total profit of the whole network and to guarantee the maximum satisfactory levels of sellers’ and buyers’ preference on sales prices. For the purpose that a compensatory solution among all participants of the supply chain can be achieved, a fuzzy decision-making method is proposed and, by means of applying it to a numerical example, proved effective in providing a compromised solution in a multi-echelon supply chain network.
Using flat cylindrical samples having non-uniform dielectric properties, we studied the heat transfer in food products when only the side surfaces of the samples were irradiated with microwaves. The temperature distributions in the food were measured by means of an infrared thermometer in two-dimensional form. Additionally, a transient two-dimensional heat conduction equation was induced and the temperature distributions in the food were determined using a numerical calculation. When the experimental results were compared with the results of the numerical calculations, their tendency of temperature distribution closely agreed, and it was confirmed that the mathematical model is useful in predicting the temperature distributions of food with non-uniform dielectric properties during microwave heating.
Recently, studies of selective separation of cells using dielectrophoresis (DEP) have been performed. However, these are not applied to a large scale separation because the separation speed was low. For the problem of the DEP separation, a DEP force is effectively acted only when it is close to the electrode. However, a DEP filter would be one of the answers for a large scale separation. In this paper, we discussed optimization of electrode geometries and arrangement of the DEP filter by using the finite element method (FEM) analysis in order to improve the separation efficiency. A DEP filter electrode using fine wire has a circular cross section, and in this case it became clear that the value of ∂E2/∂y was influenced by the diameter, and the optimum diameter was 0.6 times the electrode gap. Also we discussed for various electrode geometries such as circular, square, diamond, and equilateral triangle electrodes. It became clear that the optimal cross sectional geometry of the DEP filter electrode was square.
From the viewpoints of energy and environmental problems in the world, development of chemical heat pump technology and its practical uses are required. A chemical heat pump using a reversible calcium oxide/water reaction system has been proposed to promote thermal energy utilization. In this report three CaCO3 materials, namely, lime, scallop and coral powder, were examined on the reactivity of the hydration/dehydration of CaO/Ca(OH)2 and the possibility of scallop and coral as the alternates of limestone was discussed. CaO particles used as a reactant were prepared by the calcination of the three CaCO3 materials. The difference of the CaCO3 resource in the hydration and the dehydration reactivity of the CaO/Ca(OH)2 system was studied by the use of a closed system reactor with forced convection. The compositions of the lime, coral and scallop powder were almost the same, while hydration conversions of the three materials were different from each other. Especially the reactivity of the scallop powder was considerably low in comparison with the other two materials. However, the difference among these hydration conversions disappeared by the repetition of hydration/dehydration reactions. The hydration conversions of three materials prepared by the repetition of reactions agreed well with one calculated by a model proposed by the authors. CaO made from the scallop with reaction repetition has almost as high a reaction capacity as CaO made by calcination of lime and coral.
Natural manganese ores were selected as the main active component for a non-zinc desulfurization sorbent used in the gas clean-up process of the integrated gasification combined cycle (IGCC) because of excellent H2S removal efficiency and economical aspect. In this study, the regeneration characteristics of a sorbent after a desulfurization reaction was determined in a thermobalance reactor and a fixed bed reactor in the temperature range of 823–1123 K. A mixed gas of oxygen and nitrogen was used as the regeneration reaction gas for the manganese sorbent. According to an Mn-S-O phase diagram, the manganese sorbent has a low regeneration efficiency in medium temperautre due to the formation of MnSO4 and the regeneration temperature must be over 1123 K. To improve this problem, ammonia and steam was added in the regeneration mixed gas. The effect of the new regeneration method was determined by XRD and difference of desulfurization through multi-cycle tests in a fixed bed reactor.
In recent years, with increasing global warming and fossil fuel resource depletion, biodiesel has become a possible alternative to diesel fuel from the viewpoint of emission control. Biodiesel fuel is produced from renewable natural bio-sources and is easily combustible, and therefore various processes involved in biodiesel fuel production have been recently developed. In the present study, we produced biodiesel transportation fuel from fish waste oil using ozone treatments and evaluated its properties as an alternative to diesel fuel. Ozone treatment lowered the flash point of the produced fuel, resulting in easy combustibility. Quantitative changes in the amounts of fatty acids that form triglycerides and hydrocarbons in three oil samples (untreated and ozone treated) were also shown. Total ion chromatograms produced from gas chromatography mass spectrometry (GC/MS) revealed that the fatty acid compositions of fish waste oil decompose giving rise to hydrocarbons. The ozone treated fish waste oil was considered to be a suitable alternative to diesel fuel from the viewpoint of fuel quality and exhaust gases.
Glucose-glycine was treated under hot compressed water at temperatures higher than 423 K. The yields of oil and diethyl ether extracts within the aqueous phase increased with the increase in reaction temperature. Analysis by GC-MS revealed that pyrazines and pyridines were among the compounds in the oil and aqueous phases detected as the primary nitrogen-containing compounds. These nitrogen-containing compounds were formed from the degradation of melanoidin derivatives, the reaction products of sugars and amino acids. In this report, we propose one possible mechanism by which these pyrazines and pyridines compounds are obtained.