350 research outputs found

    Synergistic multi-doping effects on the Li7La3Zr2O12 solid electrolyte for fast lithium ion conduction.

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    Here, we investigate the doping effects on the lithium ion transport behavior in garnet Li7La3Zr2O12 (LLZO) from the combined experimental and theoretical approach. The concentration of Li ion vacancy generated by the inclusion of aliovalent dopants such as Al(3+) plays a key role in stabilizing the cubic LLZO. However, it is found that the site preference of Al in 24d position hinders the three dimensionally connected Li ion movement when heavily doped according to the structural refinement and the DFT calculations. In this report, we demonstrate that the multi-doping using additional Ta dopants into the Al-doped LLZO shifts the most energetically favorable sites of Al in the crystal structure from 24d to 96 h Li site, thereby providing more open space for Li ion transport. As a result of these synergistic effects, the multi-doped LLZO shows about three times higher ionic conductivity of 6.14 × 10(-4) S cm(-1) than that of the singly-doped LLZO with a much less efforts in stabilizing cubic phases in the synthetic condition

    Acute Effect of Active Tibial Rotation Exercise on Tibial Torsion Angle, Ankle Range of Motion, and Neuromuscular Control

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    PURPOSE This study aimed to analyze the acute effect of active tibial rotation exercise on tibial torsion angle, ankle range of motion, and neuromuscular control. METHODS This study was based on AB/BA Cross-over design, and participants were divided into two conditions (core-tex tibial and manual tibial rotation exercises). Before and after the exercise intervention, tibial torsion angle, non-weight bearing ankle range of motion, weight-bearing ankle range of motion and dynamic balance test, and Shark skill test were conducted. RESULTS An interaction effect was found in the left non-weight-bearing ankle range of motion and the right posterolateral (PL) of the Y Balance Test. In addition, there were significant differences between periods in left tibial torsion angle, non-weight-bearing ankle range of motion, bilateral weight-bearing ankle range of motion, bilateral AN, bilateral posteromedial, right PL, bilateral composite score, and bilateral Shark skill test. CONCLUSIONS Tibial rotation exercise is considered valuable as sports injury prevention training due to its effectiveness for lower extremities functionally and structurally regardless of tibial rotation exercise type

    Development of a bycatch reduction device (BRD) for shrimp beam trawl using flexible materials

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    This study aimed to design a bycatch reduction device (BRD) for shrimp beam trawl, which is manufactured by flexible materials to reduce bycatch for the gear in the South Sea of Korea. The model test was carried out to understand the shape of the gear in the water and to measure the variation of flow speed due to the BRD in a circulating water channel. Catches were compared between a shrimp beam trawl without BRD (control gear) and others with BRD (treatment gears) in the field. BRDs were two different types in this study. In the case of BRD (a), a square-shaped grid net and a funnel-shaped net were installed in the front part of the cod end to help fish sorting and expelling through the outlet at the bottom. BRD (b) has one more outlet which is added at the upper part of the BRD (a). On the model test, water speed was reduced a little in the gear by installing the BRD. At the results of comparing with a control gear, the bycatch (%) of fish excluding shrimp was reduced between 17 and 68% using BRD (a) and 5 and 66% for BRD (b) respectively. By the signed test of significant level 0.05, the quantity of shrimp catches for BRD (a) was not different in comparison to the control gear but it decreased for the gear installing BRD (b)

    Cytohistological study of the leaf structures of Panax ginseng Meyer and Panax quinquefolius L.

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    AbstractBackgroundBoth Panax ginseng Meyer and Panax quinquefolius are obligate shade-loving plants whose natural habitats are broadleaved forests of Eastern Asia and North America. Panax species are easily damaged by photoinhibition when they are exposed to high temperatures or insufficient shade. In this study, a cytohistological study of the leaf structures of two of the most well-known Panax species was performed to better understand the physiological processes that limit photosynthesis.MethodsLeaves of ginseng plants grown in soil and hydroponic culture were sectioned for analysis. Leaf structures of both Panax species were observed using a light microscope, scanning electron microscope, and transmission electron microscope.ResultsThe mesostructure of both P. ginseng and P. quinquefolius frequently had one layer of noncylindrical palisade cells and three or four layers of spongy parenchymal cells. P. quinquefolius contained a similar number of stomata in the abaxial leaf surface but more tightly appressed enlarged grana stacks than P. ginseng contained. The adaxial surface of the epidermis in P. quinquefolius showed cuticle ridges with a pattern similar to that of P. ginseng.ConclusionThe anatomical leaf structure of both P. ginseng and P. quinquefolius shows that they are typical shade-loving sciophytes. Slight differences in chloroplast structure suggests that the two different species can be authenticated using transmission electron microscopy images, and light-resistant cultivar breeding can be performed via controlling photosynthesis efficiency

    ICONE14-89044 APERIODIC INSTABILITY OF A ONCE-THROUGH STEAM GENERATOR WITH A FEEDWATER LINE

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    ABSTRACT Aperiodic (static) flow instability is an instability related to the change of a flow direction in individual steam generating U-shaped channels operating at given pressure difference. The nature of an aperiodic instability is close to a Ledinegg instability INTRODUCTION The hydrodynamic stability of OTSG, in particular OTSG in nuclear power plant, is one of the most important conditions ensuring their reliable operation. The operation of a OTSG under unstable conditions can damage the heating surface as a result of overheating or temperature fluctuations, and lead to a decrease of the heat reception It is known that two types of instability are possible for the OTSG [3]: a parallel-channel instability in the system of the channels connected in parallel and an aperiodic instability in the system of the U-shaped channels: Hydrodynamic instability of the OTSGs in terms of steamwater flow fluctuations occurs in the system of parallel channels and operating at a permanent pressure difference. It should be noted that it is typical for the OTSG to operate in low flow and low pressure conditions. The main disturbance source in a steam-water channel, finally leading to flowrat

    An MTCMOS design methodology and its application to mobile computing

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