Effect of potassium addition on bimetallic PtSn supported θ-Al₂O₃ catalyst for n-butane dehydrogenation to olefins

Nagaraja, B.M.,Jung, H.,Yang, D.R.,Jung, K.D. Elsevier Science Publishers 2014 CATALYSIS TODAY - Vol.232 No.-

PtSn/θ-Al<SUB>2</SUB>O<SUB>3</SUB> catalysts with different amount of potassium (0.4, 0.7, 0.95, 1.2 and 1.45wt.%) were prepared by an impregnation method, and their catalytic activity in n-butane dehydrogenation was investigated at 823K, an atmospheric pressure and a GHSV of 18,000mL(g<SUB>cat</SUB>h)<SUP>-1</SUP>. The compositions listed in order of n-C<SUB>4</SUB><SUP>=</SUP> yields at 823K were as follows: K<SUB>0.95</SUB>(PtSn)<SUB>1.5</SUB>>(PtSn)<SUB>1.5</SUB>>K<SUB>0.4</SUB>(PtSn)<SUB>1.5</SUB>>K<SUB>0.7</SUB>(PtSn)<SUB>1.5</SUB>>K<SUB>1.2</SUB>(PtSn)<SUB>1.5</SUB>>K<SUB>1.45</SUB>(PtSn)<SUB>1.5</SUB>>K<SUB>0.9</SUB>(Pt)<SUB>1.5</SUB>. The K<SUB>0.9</SUB>(Pt)<SUB>1.5</SUB> and K<SUB>0.95</SUB>(Sn)<SUB>1.5</SUB> catalyst severely deactivated in n-butane dehydrogenation. The (PtSn)<SUB>1.5</SUB> (without K) catalyst showed the highest n-butane conversion, while K<SUB>0.95</SUB>(PtSn)<SUB>1.5</SUB> did the highest n-C<SUB>4</SUB><SUP>=</SUP> yield. The small amount of potassium on bimetallic PtSn/θ-Al<SUB>2</SUB>O<SUB>3</SUB> catalyst improved n-C<SUB>4</SUB><SUP>=</SUP> selectivity, but slightly decreased n-butane conversion, resulting in the increase of n-C<SUB>4</SUB><SUP>=</SUP> yield. The effect of potassium was caused by blocking the acid sites of Pt catalyst. The TPR and HAADF STEM-EDS study suggested the reduction procedure of the Pt, Sn and K species. However, the higher loaded potassium (1.2 and 1.45wt.%) doped (PtSn)<SUB>1.5</SUB> catalysts were rather highly deactivated because the sizes of Pt particles were increased by weakening the interaction between Pt and Sn. The n-C<SUB>4</SUB><SUP>=</SUP> selectivity of the (PtSn)<SUB>1.5</SUB> catalyst increased with respect to the reaction, while that of the potassium doped catalysts maintained the high n-C<SUB>4</SUB><SUP>=</SUP> selectivity from the beginning of the reaction. Also, different alkali metals (Ca, Na and Li) were tested for the comparison with K. The potassium doped catalyst showed the highest n-C<SUB>4</SUB><SUP>=</SUP> yield among the other alkali metals for n-butane dehydrogenation.

Effect of Different Spray Dried Plasmas on Growth, Ileal Digestibility, Nutrient Deposition, Immunity and Health of Early-Weaned Pigs Challenged with E. coli K88

Bosi, P.,Han, In K.,Jung, H.J.,Heo, K.N.,Perini, S.,Castellazzi, A.M.,Casini, L.,Creston, D.,Gremokolini, C. Asian Australasian Association of Animal Productio 2001 Animal Bioscience Vol.14 No.8

A total of 96 piglets were weaned at 19 and 13 days in Exp. 1 and 2, respectively, and allotted to one of four diets: three with different spray dried plasmas (SPs) and one with hydrolysed casein (HC). SPs were from pigs (SPP), mixed origin (SMP), and mixed origin with standardized level of immunoglobulins (SMPIG). All the diets contained 1.7% total lysine, 25% of the test protein source, 45% corn starch, 15% lactose, 2% sucrose, 7% soybean oil. At d 4 and d 2 in Exp. 1 and 2, respectively, piglets were perorally challenged with $10^{10}$ CFU E. coli K88. Growth performance, immunity, and health condition were measured for 15 days and 14 days in Exp. 1 and 2, respectively. To investigate apparent ileal digestibility and nutrient deposition, all piglets were sacrificed at d 14 in Exp. 2. In 1. 3 piglets died in HC diet and 1 in SPP diet. HC diet showed higher mortality (p<0.01) than other diets. In Exp. 2, no clinical sign of infection was detected, no difference for the content of E. coli K88 was found in feces at 4 and 6 days after the infection, and no E. coli K88 was found in the jejunum at the end of experiment. In both experiments, feed intake was lower for HC diet and ADG was 96, 106, 122 and 155 for HC, SPP, SMP and SMPIG diet, respectively (HC vs others, p<0.05; SMPIG vs other SP, p<0.01). Heal apparent digestibility of nitrogen in sacrificed piglets was higher for HC diet (p<0.05). After the challenge, K88-specific titers in saliva (Exp. 1) and in plasma (Exp. 2) were reduced in SMP and SMPIG. The piglets positive to the adhesion of the used E. coli strain to the intestinal brush borders had a significantly reduced growth (p<0.01) and a higher K88-specific IgA titer in plasma, in comparison with negative ones. This effect was independent of the diet. The data show the relevance of spray dried plasma sources and particularly of SP with standardized level of immunoglobulins for the feeding of early-weaned at the risk of infection by enterotoxigenic bacteria.

Inactivation of HDAC3 and STAT3 is Critically Involved in 1-Stearoyl-sn-Glycero-3-Phosphocholine-Induced Apoptosis in Chronic Myelogenous Leukemia K562 Cells

Jung, J. H.,Jeong, S. J.,Kim, J. H.,Jung, S. K.,Jung, D. B.,Lee, D.,Sohn, E. J.,Yun, M.,Lee, H. J.,Lee, H. J. HUMANA PRESS INC 2013 Cell biochemistry and biophysics Vol.67 No.3

DISCRETE SOBOLEV ORTHOGONAL POLYNOMIALS AND SECOND ORDER DIFFERENCE EQUATIONS

Jung, H.S.,Kwon, K.H.,Lee, D.W. Korean Mathematical Society 1999 대한수학회지 Vol.36 No.2

Let {Rn($\chi$)}{{{{ { } atop {n=0} }}}} be a discrete Sobolev orthogonal polynomials (DSOPS) relative to a symmetric bilinear form (p,q)={{{{ INT _{ } }}}} pqd$\mu$0 +{{{{ INT _{ } }}}} p qd$\mu$1, where d$\mu$0 and d$\mu$1 are signed Borel measures on . We find necessary and sufficient conditions for {Rn($\chi$)}{{{{ { } atop {n=0} }}}} to satisfy a second order difference equation 2($\chi$) y($\chi$)+ 1($\chi$) y($\chi$)= ny($\chi$) and classify all such {Rn($\chi$)}{{{{ { } atop {n=0} }}}}. Here, and are forward and backward difference operators defined by f($\chi$) = f($\chi$+1) - f($\chi$) and f($\chi$) = f($\chi$) - f($\chi$-1).

Surface characteristics and biological response of titanium oxide layer formed via micro-arc oxidation in K₃PO₄ and Na₃PO₄ electrolytes

Jung, Y.C.,Shin, K.R.,Ko, Y.G.,Shin, D.H. Elsevier Sequoia 2014 JOURNAL OF ALLOYS AND COMPOUNDS Vol.586 No.suppl1

The present work demonstrated the influence of phosphate electrolytes on surface characteristics and biological response of the titanium oxide layer formed via micro-arc oxidation coating. For this purpose, the present coatings were carried out on titanium samples using two different electrolytes containing Na<SUB>3</SUB>PO<SUB>4</SUB> and K<SUB>3</SUB>PO<SUB>4</SUB>. The surface roughness of the oxide layer formed in K<SUB>3</SUB>PO<SUB>4</SUB> electrolyte was higher than that in the Na<SUB>3</SUB>PO<SUB>4</SUB> electrolyte. This was attributed to the higher fraction of the micropores in the oxide layer prepared by the K<SUB>3</SUB>PO<SUB>4</SUB> electrolyte than that by the Na<SUB>3</SUB>PO<SUB>4</SUB> electrolyte. From the results of simulated body fluid test, the precipitation and growth of amorphous calcium phosphate on the oxide layer formed in the K<SUB>3</SUB>PO<SUB>4</SUB> electrolyte was superior to that in the Na<SUB>3</SUB>PO<SUB>4</SUB> electrolyte due to the enhanced surface roughness. In addition, in vitro cell adhesion was triggered in case of the oxide layer formed in the K<SUB>3</SUB>PO<SUB>4</SUB> electrolyte.

Thixoforging을 위한 알루미늄 합금의 압축 D/B구축

정경득(K.D.Jung),강충길(C.G.Kang) 한국정밀공학회 1999 한국정밀공학회 학술발표대회 논문집 Vol.1999 No.11월

The ''self spin valve'' in oxygen stoichiometric SrRu_1-xFe_xO_3-δ epitaxial thin films

Toreh, K.R.N.,Kim, D.H.,Dash, U.,Phan, T.L.,Lee, B.W.,Jin, H.W.,Lee, S.,Park, B.H.,Park, J.Y.,Cho, M.R.,Park, Y.D.,Acharya, S.K.,Yoo, W.,Jung, M.H.,Jung, C.U. Elsevier Sequoia 2016 Journal of alloys and compounds Vol.657 No.-

SrRu<SUB>1-x</SUB>Fe<SUB>x</SUB>O<SUB>3-δ</SUB> (x = 0.00, 0.05, 0.10, and 0.20) thin films were fabricated to study the intrinsic aspects of a ''self spin valve''. Using epitaxial strain and high oxygen partial pressure during thin film growth, single phase thin films with negligible oxygen vacancies were successfully grown, and problems related to A-site disorder and grain boundaries were minimized. Under application of an external magnetic field of up to 9 T, the resistivity of all films decreased, resulting in large negative magnetoresistance (up to ~14.4%), which was stronger at temperatures in the range 10-30 K. An abrupt metal-insulator transition at T~ 43 K was found in the x = 0.20 film, which was explained using a two-fluid model related to electron-electron interactions. From the model, two fitting parameters were found to be necessary for in-situ and homogenous defects, while three or unphysical fitting parameters were necessary for ex-situ and inhomogeneous defects.

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>

Structural and thermoelectric properties of hydrothermal-processed Ag-doped Fe₂O₃

Park, K.,Hong, H.Y.,Jung, G.W.,Kim, D.H.,Hakeem, D.A.,Iqbal, A. Elsevier 2018 Ceramics international Vol.44 No.13

<P><B>Abstract</B></P> <P>Fe<SUB>2-<I>x</I> </SUB>Ag<SUB> <I>x</I> </SUB>O<SUB>3</SUB> (0 ≤ <I>x</I> ≤ 0.04) nanopowders with various Ag contents were synthesized at different hydrothermal reaction temperatures (150 °C and 180 °C). Their structural properties were fully investigated through an X-ray diffraction, a Fourier transform infrared spectroscopy, and an X-ray photoelectron spectroscopy. The hydrothermal reaction temperature, time, and Ag content remarkably affected the morphological characteristics and crystal structure of the synthesized powders. The Fe<SUB>2-<I>x</I> </SUB>Ag<SUB> <I>x</I> </SUB>O<SUB>3</SUB> (0 ≤ <I>x</I> ≤ 0.04) powders synthesized at 150 °C for 6 h and the Fe<SUB>2-<I>x</I> </SUB>Ag<SUB> <I>x</I> </SUB>O<SUB>3</SUB> (0.02 ≤ <I>x</I> ≤ 0.04) powders synthesized at 180 °C for 12 h formed the orthorhombic α-FeOOH phase with a rod-like morphology, whereas the Fe<SUB>2-<I>x</I> </SUB>Ag<SUB> <I>x</I> </SUB>O<SUB>3</SUB> (0 ≤ <I>x</I> ≤ 0.01) powders synthesized at 180 °C for 12 h formed the rhombohedral α-Fe<SUB>2</SUB>O<SUB>3</SUB> phase with a spherical-like morphology. The Fe<SUB>1.98</SUB>Ag<SUB>0.02</SUB>O<SUB>3</SUB> fabricated by utilizing Fe<SUB>1.98</SUB>Ag<SUB>0.02</SUB>O<SUB>3</SUB> powders synthesized at 180 °C showed the largest power factor (0.64 ×10<SUP>−5</SUP> Wm<SUP>−1</SUP> K<SUP>−2</SUP>) and dimensionless figure-of-merit (0.0036) at 800 °C.</P>

Theoretical study on porphyrin based covalent organic polyhedra as a hydrogen storage

Kim, D.,Jung, D.H.,Guk, H.,Han, S.S.,Park, N.,Choi, K.,Choi, S.H. Pergamon Press ; Elsevier Science Ltd 2013 International journal of hydrogen energy Vol.38 No.14

We introduce a new covalent organic polyhedron (COP) containing porphyrinyl groups. The porphyrin based COP (PCOP) is designed by modeling and simulation using 6 tetraaldehyde molecules and 8 triamine molecules combined by 24 imine bonds. Probable molecular crystal structures of the modeled PCOP are suggested by the simulated annealing Monte Carlo simulation method. We found that the predicted crystal structures show large surface areas up to over 6000 m<SUP>2</SUP>/g and the surface area depends on how to pack PCOP molecules and the resulting pore structure. Grand canonical Monte Carlo simulations predict the hydrogen uptakes of these polymorphs of PCOP and the values are from 98 to 262 mg/g for gravimetric uptake and from 45 to 50 kg/m<SUP>3</SUP> for volumetric uptake at 77 K. Hydrogen uptakes of PCOP crystals are comparable to the best records of metal-organic frameworks (164.1 mg/g for NU-100 and 176 mg/g for MOF-210 at 77 K). Hence, PCOP is expected to be applicable to hydrogen storage.