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The effect of initial grain size on the flash event was examined in microcrack healing behavior under DC electric field in fine‐ and coarse‐grained 8 mol% Y2O3‐stabilized cubic ZrO2 (8Y‐CSZ) polycrystals. The healing behavior depends strongly on the initial grain size and is apparently accelerated in fine‐grained 8Y‐CSZ than in coarse‐grained one. Since the crack healing under the flash event is higher than that of static annealing treatment without the electric field, the enhanced healing phenomena cannot be explained only by the thermal effect caused by Joule heating, but nonthermal effects caused by the flash event. The grain size‐dependent healing behavior indicates that the grain boundaries play an important role in the flash event and the flash healing would be accelerated through the field/current‐enhanced diffusional processes, especially through the grain boundary diffusivity of the cations. [ABSTRACT FROM AUTHOR]

Controlling the crystallographic orientation in bulk ceramics is expected to improve their properties that depend on the axis of the crystal structure. The development of crystallographic orientation using a magnetic field has been reported in various types of bulk ceramics with anisotropic crystal structures. In this study, c‐axis–oriented AlN bulk ceramics were prepared by slip casting in a rotating high magnetic field. The c‐axes of 61% of the grains were aligned within 20°. Due to this orientation, the thermal conductivity of AlN was improved. A thermal conductivity difference of approximately 14% at room temperature was observed for the samples with different orientation axes, which is higher than its intrinsic anisotropy. [ABSTRACT FROM AUTHOR]

The ionic conduction of multiply charged ions, rather than singly charged ions, is beneficial for energy storage and sensor applications. The low mobility of multiply charged ions is one important obstacle to the implementation of these applications. Chemical methods, such as doping and solid solution formation, have been used to improve ionic conductivity. However, the apparent performance of ceramic electrolytes can be improved by the crystallographic alignment of anisotropic grains. In this study, crystal‐oriented aluminum tungstate ceramics were processed by slip casting in a strong magnetic field. The b‐axis‐ and c‐axis‐oriented aluminum tungstate ceramics can be produced by this technique. The orientation of grains along the b‐axis could enhance ionic conductivity by at least 1.77 times compared to that of a randomly oriented sample and 2.13 times compared to that of the c‐axis‐oriented sample. The results of this study suggest that this method can improve the ionic conductivity of an anisotropic material using polycrystalline processing instead of difficult single‐crystal synthesis techniques. [ABSTRACT FROM AUTHOR]

Small GeO2 single crystal was successfully grown on a polyvinyl chloride (PVC) substrate at room temperature in oversaturate aqueous solution. The oversaturated solution could be prepared at strong acid condition (pH 0) using distilled water, germanium oxide, dilute ammonia, and nitric acid. About 7 μm size of the GeO2 single crystals with quartz‐type structure was obtained by only keeping the PVC plate in the solution for about 10 days when appropriate concentration of the solution was used. The obtained GeO2 single crystals were confirmed to be constructed by {101} and {011} surfaces based on powder X‐ray diffraction pattern and particle morphology observed by scanning electron microscope. [ABSTRACT FROM AUTHOR]

Solid solutions of 12CaO·7Al2O3 (C12A7) and 12SrO·7Al2O3 (S12A7) crystals were synthesized under high pressure. X-ray diffraction patterns revealed that the lattice constants of the synthesized samples depend linearly on the compositional ratio of C12A7 and S12A7. Electron-probe X-ray microanalyses show that the chemical compositions of the crystals are represented by xC12A7·(1− x)S12A7 (0< x<1). These results indicate that the variation in the lattice constants is originated from a difference in the ionic radii of Ca2+ and Sr2+ ions. From impedance measurements, it was found that S12A7 has the highest conductivity (~1 × 10−3 Scm−1 at 550°C) among the solid solutions in the C12A7-S12A7 system. [ABSTRACT FROM AUTHOR]

Rapid economic growth and urbanization has been accompanied by the equally rapid growth of carbon dioxide emissions in China. From the perspective of urban planning, land use, transport, and carbon emissions are involved in a complex process in which they interact with each other. We need to develop a computable urban economic model for sustainable infrastructure planning strategy, which can reflect the interaction among land use, transport, and carbon emissions. Our case study of Changzhou shows that a compact city scenario generates less carbon emissions than an urban sprawl scenario, indicating that a compact urban form can be accepted as a promising solution for developing a low-carbon city. [ABSTRACT FROM AUTHOR]

Although lanthanum germanate oxyapatite (La-Ge-O) has shown good potential for use as a solid electrolyte in energy storage applications, its synthesis has been challenging by either solid- or solution-state methods. In this study, a new synthesis of La-Ge-O was developed through a coprecipitation technique, in which a highly concentrated homogeneous aqueous solution of La and Ge was prepared from aqueous ammonium germanate and lanthanum nitrate solutions with the addition of dilute nitric acid. Several precipitates were formed by pH manipulation, including an amorphous material obtained at pH > 3. Compared to the individual precipitation behaviors of the parent compounds, the amorphous precipitate was formed only from the aqueous two-component mixture, and appeared to contain both metals. This material was transformed into crystalline mixtures upon heating at 1273 K. The crystalline phases were La2Ge3O9 and hexagonal-type GeO2 when the precipitate was formed below pH 8, and the La-Ge-O and La2Ge2O7 phases when the precipitate was formed around pH 8. Product formation from the coprecipitate was discussed based on X-ray diffraction and thermal analyses. The improved availability of La-Ge-O will allow more extensive investigations of its useful properties. [ABSTRACT FROM AUTHOR]

Excitation transfer in semiconductor nanostructure is an elemental process of next generation optoelectronic devices. Energy relaxation process in exciton transfer from the lowest state of a quantum well to the lowest state of the next well was studied. The energy relaxation process is essential for the completion of the transfer. Longitudinal optical (LO) phonon assisted energy relaxation was found to be most effective for exciton injection into the lowest state of very thin quantum wells on the basis of PLE measurements. A three-quantum-well structure including a 0.6-nm thick (Zn, Cd, Mn)Se well and a 1.2-nm thick (Zn, Cd)Se well separated by a 15-nm ZnSe barrier was prepared. Energy difference of exciton in the two wells was close to the LO phonon energy. The exciton transfer efficiency between the two wells was measured as a function of external magnetic field. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Background: The role of probiotics in the armamentarium remains to be defined. The aims of this study were to investigate whether the long-time administration of Lactobacillus gasseri OLL2716 (LG21) strain can eradicate H. pylori in asymptomatic pre-school children and/or prevent H. pylori infection. Methods: A total of 440 children, from 5–7 years of age, attending a kindergarten in Thailand were screened by the Helicobacter pylori stool antigen (HpSA) test. Thereafter 132 H. pylori positive and 308 H. pylori negative children were recruited to eradication and randomized prevention arms, respectively. Children in the active and placebo treatment groups received Lactobacillus gasseri OLL2716 (LG21) containing cheese and ordinary cheese, respectively, for 12 months. Eradication was defined as reversion by HpSA at 12 months. Prevention was defined as persistently HpSA negative at 12 months. Results: Eighty-two of 132 H. pylori positive (62%) completed the eradication arm, of which 24 (29.3%) were negative at 12 months according to the HpSA test. In the randomized prevention arm, 123 of 156 (79%) and 99 of 122 (81%) completed active and placebo arms, respectively, of which 4.1% and 8.1%, respectively, were HpSA positive at 12 months based on a per-protocol analysis ( p = .21). Conclusion: Further trials are needed. [ABSTRACT FROM AUTHOR]

This paper discusses the reduction of power consumption in handheld terminals from the viewpoint of system configuration and hardware. The first part discusses system development of portable and personal communication devices, as well as performance trends relating to size, transmitter power, and standby time. We then focus on the PHS (personal handy phone system) and discuss the system technology that plays a basic role in power consumption reduction, together with its effects. The configuration of the handheld terminal from the viewpoint of the hardware, as well as the configuration techniques suited to the power consumption reduction are compared and evaluated. The effectiveness is discussed. The future trends in terminal technology are also discussed and a possible direction for research and development is indicated. © 1998 Scripta Technica, Electron Comm Jpn Pt 2, 81(3): 39–52, 1998 [ABSTRACT FROM AUTHOR]