Al2O3 was doped (0.5, 1.0. and 2.0wt.%) into the garnet-type lithium ion-conducting solid electrolyte with a nominal composition of Li7La3Zr2O12 (LLZ) by solid state reaction at 1180°C. The effect of ...the Al2O3 content in LLZ on the interface behavior with lithium metal was investigated. The lowest interface resistance was observed for 0.5wt.% Al2O3-doped LLZ, which had the highest relative density of 93.7%. The Li/Al2O3-doped LLZ/Li cell showed a short circuit after a limited polarization period. Short circuiting is considered to be due to lithium dendrite formation. The longest period until short circuit was 1000s of polarization at 0.5mAcm−2 and room temperature for the 0.5wt.% Al2O3 doped LLZ.
•Al2O3-doped Li7La3Zr2O12 (LLZ) was prepared by solid state reaction at 1180°C.•0.5wt.% Al2O3-doped LLZ exhibited the highest electrical conductivity.•A Li/Al2O3-doped LLZ/Li cell exhibited an abrupt drop in cell voltage at 0.5mA.
The phase stability of Li
7
La
3
Zr
2
O
12
(LLZ) was investigated using high temperature X-ray diffraction (HT-XRD). An Al-free tetragonal LLZ phase transformed into a non-quenchable cubic phase ...around 650 °C. The phase transformation process between the tetragonal phase and the new cubic phase showed perfect reversibility. The thermal analysis showed a pair of endothermic and exothermic peaks around 640 °C that is in good agreement with the phase transformation process observed in the HT-XRD study. The non-quenchable high temperature cubic phase showed high ionic conductivity with extraordinarily low activation energy (0.117 eV). The tetragonal phase showed another phase transformation to a low temperature (LT) cubic phase around 150-200 °C in air by absorbing CO
2
into the structure. The preferred temperature for the CO
2
absorption process was around 200 °C and the absorbed CO
2
was extracted once the temperature reached 450 °C or above resulting in the phase transformation back to the tetragonal phase. On the other hand the high temperature (HT) cubic phase which shows high ionic conductivity was stabilized by Al substitution. A Li-poor LLZ containing impurity phases such as La
2
Zr
2
O
7
and La
2
O
3
effectively reacted with γ-Al
2
O
3
resulting in the formation of a pure Al-stabilized cubic LLZ, while the stoichiometric LLZ took a much longer time to complete the Al-substitution. The result suggested that the formation of Li vacancies is the primary step in the formation of the Al-stabilized cubic phase.
The phase stability of Li
7
La
3
Zr
2
O
12
(LLZ) was investigated using high temperature X-ray diffraction (HT-XRD).
A secure communication network with quantum key distribution in a metropolitan area is reported. Six different QKD systems are integrated into a mesh-type network. GHz-clocked QKD links enable us to ...demonstrate the world-first secure TV conferencing over a distance of 45km. The network includes a commercial QKD product for long-term stable operation, and application interface to secure mobile phones. Detection of an eavesdropper, rerouting into a secure path, and key relay via trusted nodes are demonstrated in this network.
Estradiol-17β (E2) and progesterone (P4) regulate oviductal functions, providing a suitable environment for the transport and maturation of gametes, fertilization, and embryonic development. In ...addition to the E2 and P4 nuclear receptors, estrogen receptor (ESR) α and β, nuclear progesterone receptor (PGR), nongenomic mechanisms through G protein-coupled estrogen receptor (GPER1), and progesterone receptor membrane component (PGRMC) 1 and 2 mediate E2 and P4 actions. This study aimed to characterize the local endocrine environment of the oviduct by examining the oviductal E2 and P4 concentrations and their receptors' mRNA expression during the periovulatory phase. The bovine oviducts were collected in a slaughterhouse and the days postovulation were estimated according to state of the ovaries and the uterus. Samples of the ampulla and isthmus ipsilateral and contralateral to the preovulatory follicle or corpus luteum were collected on Days 19 to 21, Days 0 to 1, Days 2 to 4, and Days 5 to 7 of the estrous cycle. The effects of the estrous cycle phase and oviductal region (ampulla and isthmus) and side (ipsilateral and contralateral) were analyzed by 3-way ANOVA. Moreover, to clarify the regulatory mechanisms of the mRNA expression of hormone receptors, the effects of E2 and P4 on mRNA expression in the oviduct were examined by multiple linear regression. The oviductal endocrine milieu on Days 19 to 21 was characterized by an E2-dominant environment with high E2 and low P4, high ESR1 and PGR mRNA expression, and low ESR2, GPER1, and PGRMC2 mRNA expression, whereas the corresponding on Days 0 to 1 was characterized by the endocrine milieu without hormone dominance. The environment on Days 2 to 4 and Day 5 to 7 was characterized by opposite tendency of oviductal hormone concentrations and their receptors' mRNA expression to Days 19 to 21. Additionally, the ipsilateral oviduct had the more P4-dominant endocrine milieu, with lower E2 and higher P4 concentrations, and different expression of ESR1/2, GPER1, PGR, and PGRMC2 mRNA when compared with the contralateral oviduct on Days 2 to 4 and Days 5 to 7, except for PGRMC1. Although oviductal E2 and P4 influenced the mRNA expression of ESR1/2, GPER1, PGR, and PGRMC1/2, their effects were different between regions and sides. In summary, the oviductal endocrine milieu varies according to the estrous cycle phase and the oviductal region and side, which may be involved in the estrous cycle phase-specific and oviductal region-specific and side-specific functions.
•Precise regulation of oviductal functions is essential for conception.•Estradiol and progesterone regulate oviductal functions, providing a suitable environment.•The oviductal endocrine milieu depends on the estrous cycle phase, region, and side.•Interactions between hormone concentrations and receptor expression shape the milieu.•Such cross-talk may regulate cycle phase- and location-specific oviductal functions.
High lithium ion conductivity solid electrolytes of Li1.4FexAl0.4-xTi1.6(PO4)3 (x=0−0.4) with the NASICON-type structure were synthesized by using a sol−gel precursor. The highest electrical ...conductivity was obtained for Li1.4Fe0.25Al0.15Ti1.6(PO4)3 sintered at 1040°C for 7h in air. The total, grain boundary, and bulk conductivities of the pellet were 1.01×10-3, 2.17×10-3 and 1.81×10-3Scm-1 at 25°C, respectively. The contribution of electron (or hole) conductivity to the total conductivity was negligibly small. Li1.4Fe0.25Al0.15Ti1.6(PO4)3 was unstable in water, but stable in saturated LiOH and LiCl aqueous solutions.
•A high lithium ion conductivity was observed in Li1.4Fe0.25Al0.15Ti1.6(PO4)3.•The conductivity at room temperature was 10-3 S/cm.•This compound was stable in the saturated LiOH and LiCl aqueous solution.
Magnesium alloys are attracting engineers for their practical application to structural components. Here fatigue properties, which is essential for structural use, have been examined on extruded AZ31 ...bar under uniaxial cyclic loading by both strain and stress controlled conditions. Adding fatigue tests with mean stresses under stress controlling conditions, fatigue life evaluation method has been discussed along with the analysis of cyclic stress–strain behavior. The specimen is easy to yield in compression by twinning. This leads to the asymmetric hysteresis curves. It also tends to deform quasi-elastically during unloading from compression; this makes the plastic strain amplitude smaller to the maximum one in the hysteresis curve. These asymmetric features fairly disappear at half-life in the stress controlled tests. The fatigue lives and deformation characteristics can be expressed nicely by Manson–Coffin type equation. On the contrary, the strain controlled tests retain the asymmetry till the end and produce tensile mean stresses. The fatigue lives are unsuccessfully evaluated by the above equation. Various mean stress correction models for cubic metals are not operative in magnesium alloys. A new model has been devised adding a correction term of −
σ
m/2
E to the above mentioned Manson–Coffin type equation. Strain controlled test, as it retains pyriform shape till the end, could be evaluated more accurately with the maximum plastic strain amplitude in the hysteresis curve.
A new molecular imprinting technique using covalently immobilized hemoglobin (Hb) is described for creating Hb-specific recognition cavities on silica. Two kinds of organic silane ...(3-aminopropyltrimethoxysilane: APTMS, and trimethoxypropylsilane: TMPS) were polymerized on a surface of porous silica after the Hb template was covalently immobilized by forming imine bonds, and their influence was analyzed. The results showed that not only the silane amount but also the relative proportions play an important role in protein imprinting. Pore size distribution on Hb imprinted silica was determined by nitrogen adsorption/desorption after removing the template Hb. The Hb-imprinted silica using covalently immobilized Hb (MIPi) as a template proved superior to silica using free Hb (MIPf) regarding displacement of template Hb, and selective re-adsorption as compared with other non-template proteins. The results suggested the capacity for selective adsorption of MIPi to be not only based on the isoelectric point (pI) and protein molecular weight, but also the characteristics of protein recognition cavities imprinted on base silica.
A rechargeable aqueous lithium-air cell with a third auxiliary electrode for the oxygen evolution reaction was developed. The cell consists of a lithium metal anode, a lithium conducting solid ...electrolyte of Li sub(1+x+y)Al sub(x)(Ti,Ge) sub(2- x)Si sub(y)P sub(3-y)O sub(12), a carbon black oxygen reduction air electrode, a RuO sub(2) oxygen evolution electrode, and a saturated aqueous solution of LiOH with 10 M LiCl. The cell was successfully operated for several cycles at 0.64 mA cm super(-2) and 25 degreesC under air, where the capacity of air electrode was 2000 mAh (ProQuest: Formulae and/or non-USASCII text omitted). The cell performance was degraded gradually by cycling under open air. The degradation was reduced under CO sub(2)-free air and pure oxygen. The specific energy density was calculated to be 810 Wh kg super(-1) from the weight of water, lithium, oxygen, and carbon in the air electrode.
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