Determination of Gibbs Energy of Formation of Molybdenum-Boron Binary System by Electromotive Force Measurement Using Solid Electrolyte

The standard Gibbs energies of formation of Mo₂B, ??MoB, Mo₂B₅, and MoB₄ in the molybdenum-boron binary system were determined by measuring electromotive forces of galvanic cells using an Y₂O₃-stabilized ZrO₂ solid oxide electrolyte. The results are as follows: $$ \begin{aligned} \Updelta_{\text{f}} {\text{G}}^\circ \left( {{\text{Mo}}_{2} {\text{B}}} \right)/{\text{J}}\,{\text{mol}}^{ - 1} & = - 193100 + 44.10T \pm 700\left( {1198{\text{ K to }}1323{\text{ K}}\left( {925^\circ {\text{C to }}1050^\circ {\text{C}}} \right)} \right) \\ \Updelta_{\text{f}} {\text{G}}^\circ (\alpha {\text{MoB}})/{\text{J}}\,{\text{mol}}^{ - 1} & = - 164000 + 26.45T \pm 700\left( {1213{\text{ K to }}1328{\text{ K}}\left( {940^\circ {\text{C to }}1055^\circ {\text{C}}} \right)} \right) \\ \Updelta_{\text{f}} {\text{G}}^\circ \left( {{\text{Mo}}_{2} {\text{B}}_{5} } \right)/{\text{J}}\,{\text{mol}}^{ - 1} & = - 622500 + 117.0T \pm 3000\left( {1205{\text{ K to }}1294{\text{ K}}\left( {932^\circ {\text{C to }}1021^\circ {\text{C}}} \right)} \right) \\ \Updelta_{\text{f}} {\text{G}}^\circ \left( {{\text{MoB}}_{4} } \right)/{\text{J}}\,{\text{mol}}^{ - 1} & = - 387300 + 93.53T \pm 3000\left( {959{\text{ K to }}1153{\text{ K}}\left( {686^\circ {\text{C to }}880^\circ {\text{C}}} \right)} \right) \\ \end{aligned} $$ where the standard pressure is 1 bar (100 kPa).     

Preparation of spray-dried microparticles using Gelucire 44/14 and porous calcium silicate or spherical microcrystalline cellulose to enhance transport of water-insoluble pranlukast hemihydrate across Caco-2 monolayers

The aim of this work was to prepare spray-dried microparticles using Gelucire®44/14 (GLC) and porous calcium silicate (FLR) or spherical crystalline cellulose (M06) to enhance transport of poorly water-soluble pranlukast hemihydrate (PLH) across Caco-2 monolayers. FLR or M06 were added to the PLH–GLC aqueous mixture prepared by adding distilled water at 60 °C to a melted mixture of PLH/GLC (1/1) at a PLH–GLC/carrier ratio of 1/1 or 1/17. Spray-dried FLR microparticles have the PLH–GLC solid dispersion (SD) in their pores and spray-dried M06 microparticles have the PLH–GLC SD on their surface. The dissolutions of PLH from the spray-dried FLR (SD/FLR = 1/1), spray-dried M06 (SD/M06 = 1/1), and spray-dried M06 (SD/M06 = 1/17) microparticles in Tween 80 aqueous solution were markedly fast. The transport of PLH from the spray-dried FLR (SD/FLR = 1/1) across Caco-2 monolayers was hardly observed. The transport of PLH across Caco-2 monolayers from the spray-dried M06 (SD/M06 = 1/17) increased with time, and the transport was significantly higher compared to that from PLH powder. The addition of polyethylene glycol 1500 into GLC of the spray-dried M06 was effective to increase the transport of PLH across Caco-2 monolayers. Spray-dried microparticles of PLH using GLC and M06 are a feasible means of enhancing transport across Caco-2 monolayers.     

Analysis of clogging behaviors of diatomaceous ceramic membranes during membrane filtration based upon specific deposit

Fouling behaviors in membrane filtration of dilute suspension of polystyrene latex (PSL) were examined under constant‐pressure conditions using diatomaceous ceramic membranes which are semi‐permeable to the PSL. Flux decline behaviors were evaluated in consideration of the effect of the solid permeation through the membrane. The conventional characteristic filtration equation was modified by applying the Kozeny‐Carman equation to the filtrate flow through the membrane pores. In the model, the porosity and specific surface area of the membrane were represented by unique functions of the solid deposit retained in the membrane pores. The variations of the filtration rate and filtrate volume with the filtration time were accurately described based upon the modified characteristic filtration equation. It was revealed that the extent of the membrane blocking per unit deposit load increased with the decrease in the pore size of the membrane and with decreasing pressure, but was little influenced by the suspension concentration. © 2009 American Institute of Chemical Engineers AIChE J, 2010     

Effect of liquid metal composition and hydrodynamic parameters on cavitation erosion

Cavitation erosion testing machine for low-temperature melting alloy liquid was developed by using a vibratory apparatus. The erosion tests of SUS304 were carried out in three kinds of lead–bismuth and deionized water. We defined a relative temperature as the percentage between freezing and boiling points. At relative temperature at 14 °C, the erosion rate is 10–12 times in various lead–bismuth alloys, and 2–5 times in sodium, as compared with that in deionized water. When SUS304 was exposed to a cavitation in PbBi, the surface was work hardened 20% harder compared with original surface. In deionized water, SUS304 was work hardened by 5%. Therefore, we can conclude that larger collapse pressure can be estimated to act on the specimen surface in lead–bismuth, as compared with that in water.We discussed the effect of hydrodynamic properties on cavitation erosion in a flowing system. It is considered that the erosion rate in sodium is in proportion to 1st to 6th power of flow velocity similarly to that in mercury. The incipient cavitation number is approximately unity irrespective of test liquids. Furthermore, the relation between MDER and cavitation number is expressed as power low of function with an exponent of 2.5.     

Effect of Potato Starch Properties on Instant Noodle Quality in Wheat Flour and Potato Starch Blends

The properties of potato starch and their effect on the quality of Chinese‐style alkaline instant noodles made from wheat flour and potato starch blends were investigated. Starches were extracted from nine potato cultivars, and the phosphorus content of these starches was analyzed together with the median granule size and pasting and gelatinization properties. Instant noodles were manufactured using mixtures of wheat flour and these potato starches. A Rheoner instrument was used to evaluate three textural parameters, namely, the breaking force (BF), breaking energy (BE), and ratio of the breaking force to the breaking deformation (BF/BD), of instant noodles cooked by immersing into boiling water for 3 and 7 min. The phosphorus content, peak viscosity, and breakdown were significantly and positively correlated with the BF of the noodles cooked for 3 min and did not significantly correlate with that of those cooked for 7 min. Other quality parameters of potato starch did not affect the BF significantly. Other textural parameters of instant noodle quality, such as the BE and BF/BD, did not significantly correlate with any of the quality parameters of potato starch. The findings obtained with the use of wheat flour and potato starch blends suggest that phosphate, which is thought to enhance starch viscosity of potato starch, is important for making instant noodles with favorable texture in hardness.     

Thermal Expansion of YBa2Cu3O7_xas Determined by High-Temperature X-ray Diffraction under Controlled Oxygen Partial Pressures

The high-temperature phase relationship and thermal expansion coefficient of YBa₂Cu₃O_7-x under constant oxygen nonstoichiometry, x, were determined by high-temperature powder X-ray diffraction analysis under controlled oxygen partial pressure at temperatures up to 800^deg;C. The results are discussed based on reported nonstoichiometry data. The present study showed an orthorhombic-to-tetragonal transition near the composition x = 0.5. The lattice parameter c, perpendicular to the Cu-O plane, showed a maximum at around x = 0.7 to 0.8. In the ortho-rhombic phase, the lattice parameters a and b along the Cu-O plane were essentially constant for x < 0.2. For 0.2 < x < ∼ 0.5, a increased and b decreased with x. In the tetragonal phase, with x < ∼ 0.5, the lattice parameter a decreased with x. The thermal expansion coefficient, α, along the c-axis ranged from 19 × 10^-6 to 25 × 10^-6-K^-1, whereas a along the a- and b-axes ranged from 12 × 10^-6 to 22 × 10^-6-K^-1 at 400° to 800^deg;C, and these values were very small below 400^deg;C. It was found that a, b, and α along the a- and b-axes are smaller when the oxygen content along the respective axes is less, while the area of the ab plane and its thermal expansion coefficient are larger when the deviation of the oxygen content from the stoichiometric compositions of YBa₂Cu₃O₇ or YBa₂Cu₃O₆ is larger. Changes of x and temperature affected c more strongly than a and b.     

Molecular dynamics study on compressive strength of monocrystalline, nanocrystalline and amorphous Si mold for nanoimprint lithography

Molecular dynamics studies are carried out to investigate the compressive strengths and the failure mechanisms of monocrystalline, nanocrystalline and amorphous Si molds for nanoimprint lithography. The stress-strain characteristics and the stress distributions are analyzed for the three types of Si molds. The stress-strain characteristics show that the strength of the monocrystalline Si mold is the greatest among the three types of Si molds. The strength of the nanocrystalline Si mold decreases as the grain size decreases. This shows the Hall-Petch effect does not hold true in the grain size of nanometer order. The visualization of the stress distribution shows that the monocrystalline, nanocrystalline and amorphous Si mold fail due to the slipping of the specific atomic plane, the sliding in the grain boundaries and the nonlocal plastic deformation, respectively. As a result, the monocrystalline Si mold is the most suitable for nanoimprint lithography among the three types of Si molds in the nanoscale regime.     

Granulated metrial gland cells in the murine uterus: localization,kinetics, and the functional role in angiogenesis during pregnancy

Granulated metrial gland (GMG) cells are a major immune cell population in the murine pregnant uterus, and contribute to the maintenance of pregnancy by functioning as uterus-specific natural killer (NK) cells. In order to reveal their kinetics, activation, and functional roles in pregnancy, we conducted quantitative and immunohistochemical analyses in normal and immuno-modulator-treated mice. Under a light microscope, GMG cells were identified by red cytoplasmic granules in periodic-acid-Schiff (PAS)-stained sections. They progressively increased in number and size with the peak at day 12-14 of pregnancy in the decidua and metrial gland. New vessel formation was most prominent around day 8, and the total vascular area reached the peak at day 13. GMG cells were often located near the blood vessels, and expressed vascular endothelial growth factor (VEGF), suggesting their possible inducing role in angiogenesis during the development of decidua/metrial gland. While blood vessels in the non-pregnant uterus were negative for vascular cell adhesion molecule (VCAM)-1, those in the pregnant one were positive. Treatment with neutralizing antibody against VCAM-1, however, did not decrease the number of GMG cells. On the other hand, mitosis of GMG cells was frequently observed. These data suggest that the increment of GMG cells during pregnancy may largely result from local proliferation in the uterus rather than an increased influx of precursor cells. Although we attempted to induce in vivo activation of GMG cells by administration of interleukin-12 (IL-12) or alpha-galactosylceramide, a potent activator for natural killer-T (NK-T) cells, the number of GMG cells did not appreciably increase. The present study has demonstrated that GMG cells locally proliferate in the pregnant uterus, not being related to VCAM-1 expression by the uterine vasculature or systemic activation of NK cells and NK-T cells, and seem to be involved in angiogenesis in the pregnant uterus through VEGF production.     

Application of a macromolecular Sn (II) complex to the preparation of 99mTc radiopharmaceuticals

To develop insoluble Sn²⁺ complexes for the preparation of ^99mTc radiopharmaceuticals, the adsorption of Sn²⁺ to macroreticular chelating ion exchange resins having various functional groups was investigated. Among them, a resin containing aminophosphonic acid groups showed a high adsorption capacity for Sn²⁺, which was bound strongly to the resin by chelation. This macromolecular Sn²⁺ complex was very stable against hydrolysis and oxidation, and could be applied satisfactorily for the reduction of ^99mTc.     

Forced flow boiling heat transfer of liquid hydrogen for superconductor cooling

Heat transfer from inner side of a heated vertical pipe to liquid hydrogen flowing upward was first measured at the pressure of 0.7 MPa for wide ranges of flow rates and liquid temperatures. The heat transfer coefficients in non-boiling regime for each flow velocity were well in agreement with the Dittus–Boelter equation. The heat fluxes at the inception of boiling and the departure from nucleate boiling (DNB) heat fluxes are higher for higher flow velocity and subcooling. It was found that the trend of dependence of the DNB heat flux on flow velocity was expressed by the correlation derived by Hata et al. based on their data for subcooled flow boiling of water, although it has different propensity to subcooling.