• Journal of the Korean Vacuum Society
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• v.12 no.S1
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• pp.1-6
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• 2003

SiC-C films were deposited with r. f. magnetron sputtering on substrates followed by argon ion bombardment. These films were then permeated by hydrogen gas under the pressure of $3.23\times10^{7}$ Pa for 3 hours at temperature of 500K or bombarded with hydrogen ion beam at 5 keV and a dose of $1\times10^{18}$ ions/$\textrm{cm}^2$. SIMS, AES and XPS were used to analyze hydrogen related species, chemical bonding states of C, Si as well as contamination oxygen due to hydrogen participation in the SiC-C films in order to study the different behaviors of hydrogen in carbon-carbide films due to different hydrogen introduction. Related mechanism about the effects of hydrogen on the element of the SiC-C films was discussed in this paper.

• Bulletin of the Korean Chemical Society
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• v.13 no.5
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• pp.498-503
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• 1992

The protonation of RuH(NO)(Cyttp) resulted in the formation of $[RuH_2(NO)(Cyttp)]^+$ which is characterized as a classical cis-dihydried complex. This complex is fluxional and the intramolecular process involving a molecular hydrogen complex is proposed. This mechanism was further supported by the reactivity of this complex toward neutral 2-electron ligands. On the other hand, it failed to detect the existence of $[RuH_2(NO)(etp)]^+$ probably due to instability of the complex but the crystal structure of $[Ru(PMe_3)(NO)(etp)]^+$ formed by the protonation of RuH(NO)(etp) followed by the addition of $PMe_3$ was determined to have a trigonal bipyramidal structure with a linear NO in the equatorial plane and a facial etp ligand. The crystals are monoclinic, space group P21/n, with unit cell dimensions a = 14.130(2), b = 21.026 (3), c = 14.760 (1) ${\AA}$, ${\beta}$ = 97.88 $(l)^{\circ}$ V = 4344 ${\AA}^3$, Z = 4, R = 0.046 and $R_w$ = 0.056 for the 4779 intensities with $F_o^2 > 3{\sigma}(F_0^2)$ and the 440 variables.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.790-792
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• 2002

The resistive type superconducting fault current limiter(SFCL) is a current limiter using the Quench mechanism of superconductors. When Quench occurs in superconductors, the resistance of superconductors increases abruptly. In order to increase SFCL capacity, current limiting elements were connected in series. If the Quench current of each element was different, voltage distribution was imbalanced. This imbalance could be removed by arrangement including series and parallel connection of elements. Based on this result, an SFCL of 1.8kV/50A was designed and experimented, expecially, in terms of increasing the voltage rating.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.2
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• pp.290-301
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• 2014

The first purpose of this review is to outline some of the background information necessary to understand the mechanisms of action of fibre-degrading enzymes in non-ruminants. Secondly, the well-known and understood mechanisms are described, i) eliminating the nutrient encapsulating effect of the cell wall and ii) ameliorating viscosity problems associated with certain Non Starch Polysaccharides, particularly arabinoxylans and ${\beta}$-glucans. A third, indirect mechanism is then discussed: the activity of such enzymes in producing prebiotic oligosaccharides and promoting beneficial cecal fermentation. The literature contains a wealth of information on various non starch polysaccharide degrading enzyme (NSPase) preparations and this review aims to conclude by discussing this body of work, with reference to the above mechanisms. It is suggested that the way in which multi- versus single-component products are compared is often flawed and that some continuity should be employed in methods and terminology.

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2011.09a
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• pp.3-21
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• 2011

Laboratory experiments and numerical simulations using Particle Flow Code (PFC2D) were performed to study the effects of joint separation and joint overlapping on the full failure behavior of rock bridges under direct shear loading. Through numerical direct shear tests, the failure process is visually observed and the failure patterns are achieved with reasonable conformity with the experimental results. The simulation results clearly showed that cracks developed during the test were predominantly tension cracks. It was deduced that the failure pattern was mostly influenced by both of the joint separation and joint overlapping while the shear strength is closely related to the failure pattern and its failure mechanism. The studies revealed that shear strength of rock bridges are increased with increasing in the joint separation. Also, it was observed that for a fixed cross sectional area of rock bridges, shear strength of overlapped joints are less than the shear strength of non-overlapped joints.

• BMB Reports
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• v.47 no.4
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• pp.192-196
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• 2014

RNA polymerase II carboxyl-terminal domain (pol II CTD) phosphatases are a newly emerging family of phosphatases that are members of DXDX (T/V). The subfamily includes Small CTD phosphatases, like SCP1, SCP2, SCP3, TIMM50, HSPC129 and UBLCP. Extensive study of SCP1 has elicited the diversified roles of the small C terminal domain phosphatase. The SCP1 plays a vital role in various biological activities, like neuronal gene silencing and preferential Ser5 dephosphorylation, acts as a cardiac hypertrophy inducer with the help of its intronic miRNAs, and has shown a key role in cell cycle regulation. This short review offers an explanation of the mechanism of action of small CTD phosphatases, in different biological activities and metabolic processes.

• Journal of the Korean Chemical Society
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• v.47 no.3
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• pp.199-205
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• 2003

Complexes of uranyl ion $UO^{+2}_2$with Schiff-bases obtained by condensing glycylglycine with salicylaldehyde; 2-hydroxy-1-naphthaldehyde, 2,3-dihydroxybenzaldehyde, and 2,4-dihydroxybenzaldehyde have been synthesized and characterized through elemental analysis, conductivity measurements, magnetic susceptibility determinations, u.v., i.r. and $^1H$ nmr spectra as well as d.t.a., t.g. and d.s.c. techniques. Structures and mechanisms of thermal decomposition are proposed.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.3
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• pp.243-254
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• 1996

The main purpose of this study is to investigate the collection efficiency characteristics of a cylindrical ESP. To do that, it is necessary to analyze the electric field, gas flow field, and mechanism of particle movement by numerical simulation based on EHD model. For a gas flow field, Navier-Stokes equation involving the electric source term was solved by SIMPLE algorithm. In case of the electric field, the current continuity and electric field equations were solved by S.O.R. method. The analysis of particle movement was performed on the basis of PSI-CELL model from the Lagrangian viewpoint. The results showed that the influence on the gas flow field by the electric field is almost negligible in a cylindrical ESP. The particle drift velocity $V_P$ toward the collection surface is increased continuously by the electrostatic force due to the rise of particle charge as the particle is moving to the flow direction and the particle size becomes larger. The collection efficiency is to quitely higher with the increase of applied voltage for the same particle size, while becomes smaller as the inlet velocity is increased.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.156-157
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• 2006

The preparation of composite powders for plasma spraying by an in-house designed mechanofusion process is investigated. Results show that dry particle coating depends on the chemical and mechanical properties of powders. In metal/oxide and metal/oxide/carbide powder mixtures, fine ceramic particles coat the surface of the metallic coarser particles. A nearly rounded shape of the final composite particles is induced by the mechanical energy input with no formation of new phases. However with the carbide/metal powdered system, only an intimate mixture of components is achieved. It is suggested that the coating mechanism is governed by agglomeration and rolling phenomena.

• Advances in nano research
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• v.4 no.1
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• pp.45-50
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• 2016

Data of Raman spectroscopy from graphene and few-layer graphene (FLG) irradiated by SEM electron beam in the range of energies 0.2 -30 keV are presented. The obvious effect of damaging the nanostructures by all used beam energies for specimens placed on insulator substrates ($SiO_2$) was revealed. At the same time, no signs of structural defects were observed in the cases when FLG have been arranged on metallic substrate. A new physical mechanism of under threshold energy defect production supposing possible formation of intensive electrical charged puddles on insulator substrate surface is suggested.