Enhanced energy storage properties in PbZrO3 thin films via the incorporation of NiO

Wang X.W.,Chen J.Y.,Hu S.Y.,Yu K.X.,Yang F.,Shi Y.J.,Li J.H.,Hou M.Z.,Liu A.D.,Zheng M.M.,Yin S.Q.,Hu Y.C.,Shang J. 한국물리학회 2023 Current Applied Physics Vol.52 No.-

In this study, NiO–PbZrO3 composite films were deposited on SiO2/Si substrates buffered with LaNiO3 films via the sol-gel coating technique. The effects of NiO addition in PZO thin films on the microstructure, dielectric properties, leakage mechanism, ferroelectric properties and energy storage properties have been discussed. The dielectric constant increased with the addition of NiO, while the leakage current density decreased. Compared with pure PZO films, the maximum polarization of the composite films was improved. For the composite films prepared using the NiO precursor solution with 0.05 mol/L, the recoverable energy storage density of the NiO-PZO composite film is up to 19.6 J/cm3 under the electric field of 1038 kV/cm, which is 30% higher than that of the pure PZO film under the same conditions. Also, the energy storage efficiency of the composite film reaches 48%. Accordingly, we demonstrate a simple and convenient method by adding NiO to fabricate thin films with high energy storage performance.

Proteomic Analysis Reveals PGAM1 Altering cis-9, trans-11 Conjugated Linoleic Acid Synthesis in Bovine Mammary Gland.

Wang, T,Lee, S B,Hwang, J H,Lim, J N,Jung, U S,Kim, M J,Kang, H S,Choi, S H,Lee, J S,Roh, S G,Lee, H G American Oil Chemists' Society 2015 Lipids Vol.50 No.5

<P>cis-9, trans-11 Conjugated linoleic acid (CLA) is one of the most extensively studied CLA isomers due to its multiple isomer-specific effects. However, the molecular mechanisms of cis-9,trans-11 CLA synthesis in ruminant mammary gland are still not clearly understood. This process may be mediated, to a certain extent, by trans-11 C18:1 regulated by stearoyl-CoA desaturase-1 (SCD1) and/or its syntrophic proteins. This study aimed to investigate the effects of TVA on SCD1-mediated cis-9,trans-11 CLA synthesis in MAC-T cells and its potential molecular mechanism. Results showed that trans-11 C18:1 was continually taken up and converted into cis-9,trans-11 CLA in MAC-T cells during the 4-h incubation of 50?μM trans-11 C18:1. SCD1 protein expression increased more than twofold at 2?h (P?<?0.01) and 2.5?h (P?<?0.05) before decreasing to less than half of the normal level at 4?h (P?<?0.05). One up-regulated (RAS guanyl releasing protein 4 isoform 1 [RASGRP4]) and six down-regulated proteins (glucosamine-6-phosphate deaminase 1 [GNPDA1], triosephosphate isomerase [TPI1], phosphoglycerate mutase 1 [PGAM1], heat shock protein beta-1 [HSPB1], annexin A3 [ANXA3], thiopurine S-methyltransferase [TPMT]) were found in MAC-T cells treated with trans-11 C18:1. Of these seven identified proteins, the presence of GNPDA1 and PGAM1 was verified in several models. More trans-11 C18:1 was taken up after PGAM1 knockdown by small interfering RNA (siRNA). In conclusion, our data suggested that PGAM1 may have a negative relationship with SCD1 and seemed to be involved in cis-9, trans-11 CLA synthesis by facilitating the absorption of trans-11 C18:1 in the bovine mammary gland.</P>

DROWSY BEHAVIOR DETECTION BASED ON DRIVING INFORMATION

M. S. WANG,N. T. JEONG,K. S. KIM,S. B. CHOI,S. M. YANG,S. H. YOU,J. H. LEE,서명원 한국자동차공학회 2016 International journal of automotive technology Vol.17 No.1

Drowsy behavior is more likely to occur in sleep-deprived drivers. Individuals’ drowsy behavior detection technology should be developed to prevent drowsiness related crashes. Driving information such as acceleration, steering angle and velocity, and physiological signals of drivers such as electroencephalogram (EEG), and eye tracking are adopted in present drowsy behavior detection technologies. However, it is difficult to measure physiological signal, and eye tracking requires complex experiment equipment. As a result, driving information is adopted for drowsy driving detection. In order to achieve this purpose, driving experiment is performed for obtaining driving information through driving simulator. Moreover, this paper investigates effects of using different input parameter combinations, which is consisted of lateral acceleration, longitudinal acceleration, and steering angles with different time window sizes (i.e. 4 s, 10 s, 20 s, 30 s, 60 s), on drowsy driving detection using random forest algorithm. 20 s-size datasets using parameter combination of accelerations in lateral and longitudinal directions, compared to the other combination cases of driving information such as steering angles combined with lateral and longitudinal acceleration, steering angles only, longitudinal acceleration only, and lateral acceleration only, is considered the most effective information for drivers’ drowsy behavior detection. Moreover, comparing to ANN algorithm, RF algorithm performs better on processing complex input data for drowsy behavior detection. The results, which reveal high accuracy 84.8 % on drowsy driving behavior detection, can be applied on condition of operating real vehicles.

Evaluation of Sulfur and Multi-Walled Carbon Nanotube Composite Synthesized by Dissolution and Precipitation for Li/S Batteries

Park, J. S.,Kim, D. J.,Park, J. W.,Ryu, H. S.,Kim, K. W.,Wang, G. X.,Ahn, H. J. American Scientific Publishers 2012 Journal of Nanoscience and Nanotechnology Vol.12 No.7

<P>An elemental sulfur and multi-walled carbon nanotube (S-MWNT) composite was synthesized by dissolving sulfur in ammonium sulfides and then precipitating on MWNT. Morphology observation by scanning electron microscopy (SEM) confirmed that S-MWNT product was successfully prepared by incorporating sulfur into MWNT network. Without additional conducting material, the S-MWNT composite cathodes were prepared for electrochemical tests. The properties measured in discharge-charge cycling test showed that the composite had the initial discharge capacity of 1024 mAh g(-1), which is about 61% sulfur utilization. However, in the subsequent cycling, the capacities faded. To determine the reason of rapid capacity drop, S-MWNT composite cathodes were compared in the cycling tests with varying three kinds of electrolytes and the cathode was subjected to physical force by rolling. The changes in the cycle performances proved that the deterioration of S-MWNT composite cathodes was not related to the electrolytes but to physical bonding that may not maintain the conducting path between sulfur and MWNT.</P>

Effect of Si interlayer thickness and post-metallization annealing on Ge MOS capacitor on Ge-on-Si substrate

Yoo, O.S.,Oh, J.,Kang, C.Y.,Lee, B.H.,Han, I.S.,Choi, W.H.,Kwon, H.M.,Na, M.K.,Majhi, P.,Tseng, H.H.,Jammy, R.,Wang, J.S.,Lee, H.D. Elsevier Sequoia 2008 Materials science & engineering. B, Advanced funct Vol.154 No.-

We demonstrated the effect of post-metallization annealing and Si interlayer thickness on Ge MOS capacitor on Ge-on-Si substrate with HfO<SUB>2</SUB>/TaN. Ge outdiffusion and oxygen interdiffusion were completely suppressed by thick Si interfacial layer. As a result, formation of insufficient low-k Ge oxides was effectively inhibited. It is confirmed that gate current of Si passivated Ge MOS was decreased by Si IL and decrease of gate current, J<SUB>g</SUB> is saturated after Si IL of 2nm. It was also observed that when Si IL is thick enough to restrict Ge outdiffusion, increase of J<SUB>g</SUB> is not due to the temperature-induced Ge outdiffusion but due to the partial crystallization of HfO<SUB>2</SUB> at higher annealing temperature.

Improving mechanical and magnetocaloric responses of amorphous melt-extracted Gd-based microwires via nanocrystallization

Belliveau, H.F.,Yu, Y.Y.,Luo, Y.,Qin, F.X.,Wang, H.,Shen, H.X.,Sun, J.F.,Yu, S.C.,Srikanth, H.,Phan, M.H. Elsevier 2017 JOURNAL OF ALLOYS AND COMPOUNDS Vol.692 No.-

<P><B>Abstract</B></P> <P>We report on the structural, mechanical, and magnetocaloric properties of annealed melt-extracted Gd<SUB>53</SUB>Al<SUB>24</SUB>Co<SUB>20</SUB>Zr<SUB>3</SUB> amorphous microwires of ∼70 μm diameter. During heat treatment small islands of nanocrystallities are generated and isolated in the amorphous region for the wires. The size of the nanocrystallities ranges from 5 nm to 10 nm. The observed lattice distortion from the nanocrystallities causes changes in the magnetic properties of the wires. The annealing temperature of 100 °C has the largest strength (1845 MPa) as compared to wires annealed at other temperatures. This is likely to trigger nanophase transformation in the amorphous region and these nanocrystals have been preserved through the increase of annealing temperature. The formulation of the nanocrystalline islands is also verified by the selected-area electron diffraction (SAED). The microwires exhibit a large and reversible magnetocaloric effect (MCE), with the maximum isothermal magnetic entropy change (−Δ<I>S</I> <SUB>M</SUB>) and refrigerant capacity (<I>RC</I>) values of 9.5 J/kg K and 689 J/kg respectively for the microwire annealed at 100 °C. This <I>RC</I> is about 35%, 67%, and 91% larger than those of bulk Gd<SUB>53</SUB>Al<SUB>24</SUB>Co<SUB>20</SUB>Zr<SUB>3</SUB> (∼509 J/kg), Gd (∼410 J/kg), and Gd<SUB>5</SUB>Si<SUB>2</SUB>Ge<SUB>1.9</SUB>Fe<SUB>0.1</SUB> (∼360 J/kg) regardless of their ordering temperatures. These results demonstrate the ability to tune the mechanical and magnetic properties of the microwires by thermal annealing.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The impact of nanocrystallization in Gd<SUB>53</SUB>Al<SUB>24</SUB>Co<SUB>20</SUB>Zr<SUB>3</SUB> microwires. </LI> <LI> Enhanced mechanical strength. </LI> <LI> Enhanced magnetocaloric response. </LI> </UL> </P>

Cloning of Chicken Microsomal Glutathione S-transferase 1 Gene (MGST1) and Identification of Its Different Splice Variants

Wang, X.-T.,Zhang, H.,Zhao, C.-J.,Li, J.-Y.,Xu, G.-Y.,Lian, L.-S.,Wu, C.-X.,Deng, Xuemei Asian Australasian Association of Animal Productio 2009 Animal Bioscience Vol.22 No.2

Mammal microsomal glutathione transferase 1 (MGST1) can conjugate many toxic or carcinogenic substances and depress oxidative stress. In this study, Chicken MGST1 and its variants were cloned for the first time and were composed of 956 or 944 nucleotides. The 12 nt deletion in the exon 2 did not alter the GT-AG rule and the ORFs for the two MGST1 variants were the same, which both comprised 465 nucletides and encoded a peptide with 155 amino acids. It was found that the two different splice variants identified using RT-PCR expressed in all three organs investigated of Dwarf Brown Chicken, namely liver, spleen and shell gland. Moreover, the expression level of MGST1 mRNA in the liver of Dwarf Brown chickens was the highest (p<0.01), and there were no significant differences between the spleen and the shell gland. These results provide a base for studying the biological function of Chicken MGST1.

Bendable and flexible supercapacitor based on polypyrrole-coated bacterial cellulose core-shell composite network

Wang, F.,Kim, H.J.,Park, S.,Kee, C.D.,Kim, S.J.,Oh, I.K. Elsevier Applied Science Publishers 2016 Composites science and technology Vol.128 No.-

We report a bendable and flexible supercapacitor based on polypyrrole-coated core-shell bacterial cellulose composite networks. As an initial step, gel-type bacterial cellulose was transformed into individually ultrathin bacterial cellulose nanofibers (TOBC) with diameters of 3-5 nm, by using 2,2,6,6-tetramethylpylperidine-l-oxyl radical (TEMPO)-mediated oxidation and successive mild disintegration in water. And, PPy-TOBC core-shell nanofiber network electrodes were synthesized in situ by oxidative polymerization of pyrrole with iron (III) chloride on the TOBC nanofibers in aqueous medium. The PPy-TOBC core-shell nanofiber network electrode exhibited a high porosity (101 m<SUP>2</SUP>/g) and high conductivity (~6.63 S/cm) due to the homogenous coating of PPy nanoparticles on the TOBC nanofiber network. The as-prepared PPy-TOBC supercapacitor cell, fabricated with PVDF-EMIMBF<SUB>4</SUB> (1-Ethyl-3-methylimidazolium tetrafluoroborate) polymer electrolyte, showed a specific capacitance of 153 F/g and energy density of 21.22 Wh/kg at the current density of 0.2 A/g. Moreover, the PPy-TOBC supercapacitor exhibited an exceptionally good cyclic stability with ~93% capacitance retention after 100 cycles; it also showed good bending stability due to the mechanical failure tolerance of the nanofiber-networked electrodes. The present approach is a versatile, inexpensive, and promising way to develop the cellulose-based nanofiber network electrodes for practical energy storage applications.

Two S-wave gap symmetry for single crystals of the superconductor BaFe_1.8Co_0.2As₂

Choi, K.Y.,Kim, S.H.,Choi, C.,Jung, M.H.,Wang, X.F.,Chen, X.H.,Noh, J.D.,Lee, S.I. North-Holland 2010 Physica. C, Superconductivity Vol.470 No.suppl1

To clarify the gap structure of the iron-pnictide superconductors, we synthesized optimally doped single crystals of BaFe<SUB>1.8</SUB>Co<SUB>0.2</SUB>As<SUB>2</SUB>, which had a critical temperature, T<SUB>c</SUB>, of 23.6K. The initial M-H curve was used to find the lower critical field, H<SUB>c1</SUB>. The full range of the temperature dependence of H<SUB>c1</SUB> was explained by using a two S-wave gap symmetry. We estimate the two gap as Δ<SUB>1</SUB>(0)=1.64+/-0.2meV for the small gap and Δ<SUB>2</SUB>(0)=6.20+/-0.2meV for the large gap.

Analysis of the Radiation-Damage-Free X-ray Structure of Photosystem II in Light of EXAFS and QM/MM Data

Askerka, Mikhail,Vinyard, David J.,Wang, Jimin,Brudvig, Gary W.,Batista, Victor S. American Chemical Society 2015 Biochemistry Vol.54 No.9

<P>A recent femtosecond X-ray diffraction study produced the first high-resolution structural model of the oxygen-evolving complex of photosystem II that is free of radiation-induced manganese reduction (Protein Data Bank entries <ext-link ext-link-type='pdb' xlink:href='4UB6' xlink:type='simple'>4UB6</ext-link> and <ext-link ext-link-type='pdb' xlink:href='4UB8' xlink:type='simple'>4UB8</ext-link>). We find, however, that the model does not match extended X-ray absorption fine structure and QM/MM data for the S<SUB>1</SUB> state. This is attributed to uncertainty about the positions of oxygen atoms that remain partially unresolved, even at 1.95 Å resolution, next to the heavy manganese centers. In addition, the photosystem II crystals may contain significant amounts of the S<SUB>0</SUB> state, because of extensive dark adaptation prior to data collection.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/bichaw/2015/bichaw.2015.54.issue-9/acs.biochem.5b00089/production/images/medium/bi-2015-00089d_0004.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/bi5b00089'>ACS Electronic Supporting Info</A></P>