Selective hydrogenation of d-glucose to d-sorbitol over HY zeolite supported ruthenium nanoparticles catalysts

Mishra, D.K.,Dabbawala, A.A.,Park, J.J.,Jhung, S.H.,Hwang, J.S. Elsevier Science Publishers 2014 CATALYSIS TODAY - Vol.232 No.-

HY zeolite (HYZ) supported ruthenium (Ru) nanoparticles catalyst (Ru/HYZ) is prepared by simple impregnation method and is characterized by using energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), CO chemisorption and inductively coupled plasma (ICP) mass spectrometry. The catalyst Ru/HYZ is evaluated in hydrogenation of d-glucose and hydrogenation experiments to produce a selective product d-sorbitol were conducted batch wise in a three-phase laboratory scale reactor. The kinetics studies of d-glucose hydrogenation using the catalyst Ru/HYZ were carried out. In the operating regime studied the rate of reaction showed first orders dependency with respect to d-glucose and hydrogen. For affording maximum d-glucose conversion, yield and selectivity to d-sorbitol, the reaction conditions were also optimized.

Stoichiometric Layered Potassium Transition Metal Oxide for Rechargeable Potassium Batteries

Kim, Haegyeom,Seo, Dong-Hwa,Urban, Alexander,Lee, Jinhyuk,Kwon, Deok-Hwang,Bo, Shou-Hang,Shi, Tan,Papp, Joseph K.,McCloskey, Bryan D.,Ceder, Gerbrand American Chemical Society 2018 Chemistry of materials Vol.30 No.18

<P>K-ion batteries are promising alternative energy storage systems for large-scale applications because of the globally abundant K reserves. K-ion batteries benefit from the lower standard redox potential of K/K<SUP>+</SUP> than that of Na/Na<SUP>+</SUP> and even Li/Li<SUP>+</SUP>, which can translate into a higher working voltage. Stable KC<SUB>8</SUB> can also be formed via K intercalation into a graphite anode, which contrasts with the thermodynamically unfavorable Na intercalation into graphite, making graphite a readily available anode for K-ion battery technology. However, to construct practical rocking-chair K-ion batteries, an appropriate cathode material that can accommodate reversible K release and storage is still needed. We show that stoichiometric KCrO<SUB>2</SUB> with a layered O3-type structure can function as a cathode for K-ion batteries and demonstrate a practical rocking-chair K-ion battery. In situ X-ray diffraction and electrochemical titration demonstrate that K<SUB><I>x</I></SUB>CrO<SUB>2</SUB> is stable for a wide K content, allowing for topotactic K extraction and reinsertion. We further explain why stoichiometric KCrO<SUB>2</SUB> is unique in forming the layered structure unlike other stoichiometric K-transition metal oxide compounds, which form nonlayered structures; this fundamental understanding provides insight for the future design of other layered cathodes for K-ion batteries.</P> [FIG OMISSION]</BR>

Solubility of oxcarbazepine in eight solvents within the temperature range T=(288.15-308.15)K

Nam, K.,Ha, E.S.,Kim, J.S.,Kuk, D.H.,Ha, D.H.,Kim, M.S.,Cho, C.W.,Hwang, S.J. Academic Press 2017 The Journal of chemical thermodynamics Vol.104 No.-

In this study, the solubility of oxcarbazepine in pure methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, acetone, acetonitrile, and tetrahydrofuran was analysed across the temperature range of 288.15-308.15K under atmospheric pressure by using a solid-liquid equilibrium method. The experimental values obtained data were correlated using the modified Apelblat model at each temperature. The mole fraction solubility of oxcarbazepine in all eight pure solvents increased gradually in a temperature-dependent manner. The highest mole fraction solubility of 3.08x10<SUP>-3</SUP> at 308.15K was observed for tetrahydrofuran, followed by acetone (1.82x10<SUP>-3</SUP> at 308.15K), acetonitrile (1.22x10<SUP>-3</SUP> at 308.15K), methanol (1.11x10<SUP>-3</SUP> at 308.15K), ethanol (6.17x10<SUP>-4</SUP> at 308.15K), 1-butanol (6.17x10<SUP>-4</SUP> at 308.15K), 1-propanol (6.16x10<SUP>-4</SUP> at 308.15K), and 2-propanol (4.13x10<SUP>-4</SUP> at 308.15K). The experimental solubility in all solvents correlated well with that calculated using the modified Apelblat equation across the temperature range of (288.15-308.15)K. Therefore, the experimental solubility and correlation equations established in this study could be useful during the crystallization/purification, pre-formulation, and formulation stages of oxcarbazepine production in laboratories and related industries.

RF 스위치 적용을 위한 박막 PZT 엑추에이터의 d<SUB>31</SUB> 구동과 d<SUB>33</SUB> 구동 특성 비교

신민재(M. J. Shin),서영호(Y. H. Seo),최두선(D-S. Choi),황경현(K-H. Hwang) 한국정밀공학회 2006 한국정밀공학회 학술발표대회 논문집 Vol.2006 No.5월

In this work, we present the comparison between d<SUB>31</SUB> and d<SUB>33</SUB> mode characterization using the PZT micro-actuator for large displacement. The PZT micro-actuator consisted of Si, PZT, and Pt layer on SOI wafer. The electrode shapes were laminated and interdigitated for d<SUB>31</SUB> and d<SUB>33</SUB> mode, respectively. In order to characterize the actuation mode, we measured the displacement using laser interferometer. The maximum displacement of d<SUB>31</SUB> mode was 12.2㎛ at 10V, the actuation characterization of d<SUB>31</SUB> was better than that of d<SUB>33</SUB> mode. We estimated that displacement of d<SUB>33</SUB> mode would be larger than that of d<SUB>31</SUB> above 30V.

The Effects of Stress Related Genes on Carcass Traits and Meat Quality in Pigs

H. J. Jin,B. Y. Park,J. C. Park,I. H. Hwang,S. S. Lee,S. H. Yeon,C. D. Kim,C. Y. Cho,Y. K. Kim,K. S. Min,S. T. Feng,Z. D. Li,C. K. Park,C. I. Kim 아세아·태평양축산학회 2006 Animal Bioscience Vol.19 No.2

The current study was conducted to investigate the relationship between stress related gene and meat quality in pigs. A total number of 212 three-way cross bred (Landrace-Yorkshire횞Duroc) and 38 Duroc were sampled from the Korean pig industry to determine genotype requency of porcine stress syndrome (PSS) and heat shock protein 70 kDa (HSP70) genes and their relationship with carcass traits and longissimus meat quality. Screen of HSP70 was performed by the single strand conformation polymorphism (SSCP) technique. Based on the analysis of restriction fragment length polymorphism (RFLP) in ryanodine receptor 1 (RYR1) gene, genetic disorder of PSS was related to a mutation at 18,168th (C to T) of exon 17. There was no significant difference in ultimate meat pH and backfat thickness between HSP70 K1-AA type and -BB type in pure Duroc breed. In Landrace-Yorkshire횞Duroc (L-YxD) cross bred pig, our results indicated that HSP70 derivate type in Duroc had a limited effect on backfat thickness, but L-YxD type had a noticeable linkage with HSP70 K1-AA and K3-AB. This tendency was also observed in hot carcass weight where HSP70 K1-AA and K3-AB resulted in heavier weight with 86.3 kg compared to HSP70 K1-AB and K3-BB of 74.3 kg. Results imply that stress related HSP70 genotype has a potential association with backfat thickness and carcass weight.

Experimental study of flow boiling heat transfer and dryout characteristics at low mass flux in helically-coiled tubes

Hwang, K.W.,Kim, D.E.,Yang, K.H.,Kim, J.M.,Kim, M.H.,Park, H.S. North-Holland Pub. Co 2014 Nuclear engineering and design Vol.273 No.-

The goals of this study were to understand flow boiling phenomena in helically-coiled tubes and to predict their flow boiling heat transfer coefficients (HTC) and dryout qualities. Flow heat transfer and dryout were experimentally investigated in coiled tubes of 12-mm inside diameter and 17-mm outside diameter. The helical diameters D<SUB>h</SUB> of the coiled tubes used were 606mm and 977mm for the HTC experiments and 606mm, 977mm, and 1290mm for the dryout experiments. In flow boiling experiments mass flux G was 88.4-530.5kg/(m<SUP>2</SUP>s), system pressure P was 1-6MPa, and heat flux q'' to the tube wall was 30.0-1145.3kW/m<SUP>2</SUP>. For dryout experiments, q'' was 131.3-1764.9kW/m<SUP>2</SUP>. Flow boiling heat transfer in the coiled tubes was significantly affected by nucleate boiling and convective boiling, and not by secondary flow due to the helical coiling. HTC in the coiled tubes were accurately predicted (standard deviation 29%) by Steiner and Taborek HTC correlation for straight vertical tubes. Dryout qualities were significantly influenced by the coiled tubes. The effects of D<SUB>h</SUB>, G, and P were greatly affected by secondary flow caused by the coiled tubes. Dryout in the coiled tubes can be only predicted using dryout correlations for them. The dryout map proposed by Berthoud and Jayanti was modified to consider the effects of redeposition and gravity; this modified correlation accurately predicted dryout qualities (standard deviation 10.1%) within the range of experimental conditions. These results will help guide design of cooling systems that use helical coils.

Development of a Dual Membrane Protein Reporter System Using Sodium Iodide Symporter and Mutant Dopamine D₂ Receptor Transgenes

Hwang, D. W.,Kang, J. H.,Chang, Y. S.,Jeong, J. M.,Chung, J.-K.,Lee, M. C.,Kim, S.,Lee, D. S. Society of Nuclear Medicine 2007 The Journal of nuclear medicine Vol.48 No.4

OGLE-2017-BLG-0173Lb: Low-mass-ratio Planet in a “Hollywood” Microlensing Event

Hwang, K.-H.,Udalski, A.,Shvartzvald, Y.,Ryu, Y.-H.,Albrow, M. D.,Chung, S.-J.,Gould, A.,Han, C.,Jung, Y. K.,Shin, I.-G.,Yee, J. C.,Zhu, W.,Cha, S.-M.,Kim, D.-J.,Kim, H.-W.,Kim, S.-L.,Lee, C.-U.,Lee, American Astronomical Society 2018 The Astronomical journal Vol.155 No.1

<P>We present microlensing planet OGLE-2017-BLG-0173Lb, with planet-host mass ratio of either q similar or equal to 2.5 x 10(-5) or q similar or equal to 6.5 x 10(-5), the lowest or among the lowest ever detected. The planetary perturbation is strongly detected, Delta chi(2) similar to 10000, because it arises from a bright (therefore, large) source passing over and enveloping the planetary caustic: a so-called 'Hollywood' event. The factor similar to 2.5 offset in q arises because of a previously unrecognized discrete degeneracy between Hollywood events in which the caustic is fully enveloped and those in which only one flank is enveloped, which we dub 'Cannae' and 'von Schlieffen,' respectively. This degeneracy is 'accidental' in that it arises from gaps in the data. Nevertheless, the fact that it appears in a Delta chi(2) = 10000 planetary anomaly is striking. We present a simple formalism to estimate the sensitivity of other Hollywood events to planets and show that they can lead to detections close to, but perhaps not quite reaching, the Earth/Sun mass ratio of 3 x 10(-6). This formalism also enables an analytic understanding of the factor similar to 2.5 offset in q between the Cannae and von Schlieffen solutions. The Bayesian estimates for the host mass, system distance, and planet-host projected separation are M = 0.39(-0.24)(+0.40) M circle dot, D-L = 4.8(-1.8)(+1.5) kpc, and a(perpendicular to) = 3.8 +/- 1.6 au, respectively. The two estimates of the planet mass are m(p) = 3.3(2.1)(+3.8) M circle plus and m(p) = 8(6)(+11) M circle plus. The measured lens-source relative proper motion mu = 6 mas yr(-1) will permit imaging of the lens in about 15 years or at first light on adaptive-optics imagers on next-generation telescopes. These will allow one to measure the host mass but probably will not be able to resolve the planet-host mass-ratio degeneracy.</P>

Effective suppression of C5a-induced proinflammatory response using anti-human C5a repebody

Hwang, D.E.,Choi, J.M.,Yang, C.S.,Lee, J.j.,Heu, W.,Jo, E.K.,Kim, H.S. Academic Press 2016 Biochemical and biophysical research communication Vol.477 No.4

The strongest anaphylatoxin, C5a, plays a critical role in the proinflammatory responses, causing the pathogenesis of a number of inflammatory diseases including sepsis, asthma, and rheumatoid arthritis. Inhibitors of C5a thus have great potential as therapeutics for various inflammatory disorders. Herein, we present the development of a high-affinity repebody against human C5a (hC5a), which effectively suppresses the proinflammatory response. A repebody scaffold composed of leucine-rich repeat (LRR) modules was previously developed as an alternative protein scaffold. A repebody specifically binding to hC5a was selected through a phage display, and its affinity was increased up to 5 nM using modular engineering. The repebody was shown to effectively inhibit the production of C5a-induced proinflammatory cytokines by human monocytes. To obtain insight into a mode of action by the repebody, we determined its crystal structure in complex with hC5a. A structural analysis revealed that the repebody binds to the D1 and D3 regions of hC5a, overlapping several epitope residues with the hC5a receptor (hC5aR). It is thus likely that the repebody suppresses the hC5a-mediated immune response in monocytes by blocking the binding of hC5a to its receptor. The anti-hC5a repebody can be developed as a potential therapeutic for C5a-involved inflammatory diseases.

방사선 중합에 의한 폴리프로필렌 부직포-아크릴산 공중합체의 합성과 금속 흡착 특성에 관한 연구

손원근,신경섭,황대성,황택성,황의환 忠南大學校 産業技術硏究所 1998 산업기술연구논문집 Vol.13 No.2

The PP-g-AAc copolymers were synthesized by the irradiation grafting reaction of acrylic acid onto polypropylene nonwoven fabrics. The physicochemical properties of PP-g-AAc copolymers, such as structure, thermal stability and morphology were investigated by using FT-IR, TGA and SEM analyzer. It was observed that the degree of grafting increased linearly with the increase of acrylic acid monomer concentration. After the adsorption of metal ions in PP-g-AAc copolymers, their morphology seemed like small brain, lump and sponge.