Effect of annealing on charging properties of electret fibers

In the present work, effect of annealing on charging and surface morphology of isotactic polypropylene (PP) filaments was reported. To enhance the surface crystallinity of the filaments, samples were annealed at 70 and 110 °C for 12 h. As expected, fiber surface crystallinity increased upon annealing which led more stable electret fibers. However, the change in the initial surface potential was not so remarkable. The same trend was also observed in filaments containing a commercial nucleating agent, NA11 (sodium 2,2′-methylene-bis(4,6-di-tertbutylphenyl)-phosphate). Surface crystallinity was analyzed using the intensity of specific peaks obtained from attenuated total reflection infrared spectroscopy analysis. The surface charge characteristics of fibers were determined using a modified surface potential decay test.     

Residue analysis of picoxystrobin in oriental melon using gas chromatography coupled with electron capture detection and mass spectrometric confirmation: application to dissipation kinetics and risk assessment

Food Science and Biotechnology - This study was carried out to determine the residual amounts of picoxystrobin in oriental melon (Cucumis melo L.) grown under plastic house conditions at two...     

Decline pattern and risk assessment of cyenopyrafen in different varieties of Asian pear using liquid chromatography and tandem mass spectrometry

Food Science and Biotechnology - The dissipation pattern of a commercial cyenopyrafen formulation sprayed at the recommended dose on Asian pears (two different species) grown at two different sites...     

High-quality high-k HfON formed with plasma jet assisted PVD process and application as tunnel dielectric for flash memories

We demonstrate low-trap-density HfON film made by the molecular-atomic deposition (MAD) technique, which is an Ar/N₂ plasma jet assisted physical vapor deposition process. This high-k HfON can be deposited on top of the nearly trap-free MAD-Si₃N₄ to form a single-side crested tunnel barrier. The Al/(HfON-Si₃N₄)/Si capacitor structure with HfON/Si₃N₄ stack as the tunnel barrier demonstrates steeper I-V slope than that of a single layer SiO₂ with the same EOT, and is readily applicable to improve the programming speed and data retention of flash memories.     

Effects of Trioctyl Phosphate and Cresyl Diphenyl Phosphate as flame-retarding additives for Li-Ion battery electrolytes

Safety concerns related to lithium-ion batteries have been the key obstacle to their application in hybrid electric vehicles. Trioctyl Phosphate (TOP) and Cresyl Diphenyl Phosphate (CDP) were studied as potential flame-retarding additives for lithium-ion batteries. The electrochemical performance and thermal stability of the additive-containing electrolytes, in combination with a cell comprising a LiCoO₂ cathode and Mesocarbon Microbeads (MCMB) anode, were tested in coin cells. Cyclic Voltammetry (CV), Differential Scanning Calorimetry (DSC), Electrochemical Impedance Spectroscopy (EIS), and Scanning Electron Microscopy (SEM) were used for the experimental analysis. The study results revealed that CDP addition at 5 wt.% improved the cell stability due to the lower rate of the charge-transfer resistance increase over 30–50 cycles. CDP was demonstrated to be a better flame-retarding additive than TOP.     

Microstructure development in mechanically alloyed yttria dispersed austenitic steels

Austenitic oxide dispersion strengthened (ODS) alloys containing 0.5 and 5 wt.% yttria were prepared from elemental powders (Fe–20% Ni–14% Cr–2.5% Mo–2.5% Al–2% Mn) by mechanical alloying. The powders were analyzed using X-ray diffraction (XRD), X-ray photoelectron spectroscopy and transmission electron microscopy (TEM), paying particular attention to the behavior of yttria. XRD and high-resolution TEM analyses show that yttria does not form a solid solution with austenite; unlike in ferritic ODS alloys, where it dissolves. Milling induces the formation of the thermodynamically favorable yttrium aluminum perovskite (YAP). Alumina from the aluminum powder in the starting blend, formed in the initial stages of milling using oxygen available from the other elemental powders, combines with yttria to form YAP. The yttria content does not affect alloy formation but reduces the crystallite size and strain significantly in the 5% yttria composition. TEM analysis of hot-pressed compacts reveals nanocrystalline particles of yttria, yttrium aluminum garnet and YAP.     

Memory retention process by balancing the neutral energy point in a brain-inspired system

This article proposes a memory retention strategy in a knowledge network structure in order to make a more efficient intelligent system. The structure and management strategy of the memory have a great influence on the efficiency of the system. In this approach, the concept of neutral energy is introduced, which is used to represent the state of the knowledge node. The energy value of the node was designed to manage the memory retention and recall process in a brain-inspired system. This strategy was applied to a virtual memory and tested with sample data.     

Empirical analysis of risk-taking behavior in IT platform migration decisions

Information technology (IT) platform migration incurs a great deal of risk because of the massive rewriting of legacy systems and a wide range of new technology adoptions. Therefore IT platform decisions need to be made in a mindful manner because of the high degree of investment risk. However, more aggressive migrations, compared to the global trend, to an open system have been observed in Korean organizations. This phenomenon defies the common understanding of IT investment risk and encourages the investigation of the elusive characteristics underlying IT investment decisions. The effect of IT decision-makers’ perceptions and risk propensity on their IT platform migration decisions is examined in the context of risky decisions. In addition to risk perception, decision-makers’ risk propensity also has a significant effect on IT investment decisions. By observing the monarchical IT governance and IT-biased careers of decision-makers, some implications of large-scale IT investment decisions are derived.     

Microstructural evolution of NbF5-doped MgH2 exhibiting fast hydrogen sorption kinetics

The microstructure of MgH₂ with 1 mol% NbF₅, prepared by high-energy ball milling (HEBM), was studied using high resolution transmission electron microscopy (HR-TEM) with an X-ray energy dispersive spectrometer (EDS) before and after hydrogen sorption cycles. The TEM samples were prepared without any air exposure by a novel, focused ion beam (FIB) system specially designed for highly air sensitive materials. During HEBM, the doping agent, NbF₅, was distributed as an extremely thin, film-like, amorphous phase along the grain boundaries of the nanocrystalline MgH₂. After 10 sorption cycles, amorphous Nb-F phase was transformed into crystalline Nb hydrides. It is believed that the Nb hydride played a decisive role in improving the sorption kinetics of MgH₂.