• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2018년도 춘계학술대회 논문집
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• pp.142.2-142.2
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• 2018

One-dimensional metal oxide nanostructures have attracted considerable research activities owing to their strong application potential as components for nanosize electronic or optoelectronic devices utilizing superior optical and electrical properties. In which, semiconducting $SnO_2$ material with wide-bandgap Eg = 3.6 eV at room temperature, is one of the attractive candidates for optoelectronic devices operating at room temperature [1, 2], gas sensor [3, 4], and transparent conducting electrodes [5]. The synthesis and gas sensing properties of semiconducting $SnO_2$ nanomaterials have become one of important research issues since the first synthesis of SnO2 nanowires. In this study, $SnO_2$ nanowire networks were synthesized on a basis of a two-step process. In step 1, Sn spheres (30-800 nm in diameter) embedded in $SiO_2$ on a Si substrate was synthesized by a chemical vapor deposition method at $700^{\circ}C$. In step 2, using the source of these Sn spheres, $SnO_2$ nanowire (20-40 nm in diameter; $1-10{\mu}m$ in length) networks on a spherical Sn surface were synthesized by a thermal oxidation method at $800^{\circ}C$. The Au layers were pre-deposited on the surface of Sn spherical and subsequently oxidized Sn surface of Sn spherical formed SnO2 nanowires networks. Field emission scanning electron microscopy and high-resolution transmission electron microscopy images indicated that $SnO_2$ nanowires are single crystalline. In addition, the $SnO_2$ nanowire is also a tetragonal rutile, with the preferred growth directions along [100] and a lattice spacing of 0.237 nm. Subsequently, the $NO_2$ sensing properties of the $SnO_2$ network nanowires sensor at an operating temperature of $50-250^{\circ}C$ were examined, and showed a reversible response to $NO_2$ at various $NO_2$ concentrations. Finally, details of the growth mechanism and formation of Sn spheres and $SnO_2$ nanowire networks are also discussed.

• 전기전자학회논문지
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• 제10권2호통권19호
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• pp.103-108
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• 2006

본 논문에서는 상위 수준 합성에서 연산자들의 스위칭 최소화를 통한 저 전력 자원 할당 알고리즘을 제안했다. 본 논문에서는 이미 스케줄링 된 CDFG를 대상으로 전력 소모의 원인이 되는 스위칭 동작을 최소화하는 자원할당 알고리즘을 제안한다. 제안된 알고리즘은 DSP 분야의 회로나 필터를 대상으로 연산자가 소모하는 전력을 최소화 하고자 한다. 스케줄링 된 CDFG상에 있는 여러 개의 연산은 자원공유를 통하여 같은 기능 장치에 구현될 수 있다. 이런 경우 두 개의 연속적인 연산의 실행사이에 각 연산의 입력 변수들이 연속적으로 변화하기 때문에 기능장치의 스위칭동작이 변하게 된다. 이때 자원할당 과정에서 기능장치의 입력 신호들 사이의 스위칭동작과 상관관계를 고려하여 소비전력을 감소시킨다. 본 논문에서 제안하는 방법을 이용하여 자원할당을 할 경우 기존 방법과 비교했을 때 그 수행속도는 사용하는 연산자의 수와 최다 제어 단계에 따라서 빨라 질 수 있다. 그리고 소모하는 전력의 경우, 작게는 8.5%에서 9.3%까지 감소효과가 있다.

• 전기전자학회논문지
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• 제10권2호통권19호
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• pp.134-140
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• 2006

본 논문에서는 상위 수준 합성에서 연산자들의 스위칭 최소화를 통한 저 전력 자원 할당 알고리즘을 제안했다. 본 논문에서는 이미 스케줄링 된 CDFG를 대상으로 전력 소모의 원인이 되는 스위칭 동작을 최소화하는 자원할당 알고리즘을 제안한다. 제안된 알고리즘은 DSP 분야의 회로나 필터를 대상으로 연산자가 소모하는 전력을 최소화 하고자 한다. 스케줄링 된 CDFG상에 있는 여러 개의 연산은 자원공유를 통하여 같은 기능 장치에 구현될 수 있다. 이런 경우 두 개의 연속적인 연산의 실행사이에 각 연산의 입력 변수들이 연속적으로 변화하기 때문에 기능장치의 스위칭동작이 변하게 된다 이때 자원할당 과정에서 기능장치의 입력 신호들 사이의 스위칭동작과 상관관계를 고려하여 소비전력을 감소시킨다. 본 논문에서 제안하는 방법을 이용하여 자원할당을 할 경우 기존 방법과 비교했을 때 그 수행속도는 사용하는 연산자의 수와 최다 제어 단계에 따라서 빨라 질 수 있다. 그리고 소모하는 전력의 경우, 작게는 8.5%에서 9.3%까지 감소효과가 있다.

• 한국식품과학회지
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• 제51권6호
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• pp.558-564
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• 2019

Hypertriglyceridemia is one of the metabolic syndrome that is often observed as a result of lipid abnormalities. It is associated with other lipids, metabolic disorders, cardiovascular disease and liver disease. Korean red ginseng is known to affect obesity, dyslipidemia, liver disease and liver function, but the mechanism of its effect is not clear. This study examined the beneficial effects of hypertriglyceridemia and the mechanism of action of Jinan red ginseng extract (JRG) in hepatoma cells. To measure the levels of triglyceride accumulation, we studied the expression of proteins and mRNAs related to lipidogenesis in hepatoma cells (Huh7 and HepG2). JRG decreases the lipidogenic markers, peroxisome proliferator-activated receptor γ (PPARγ), CCAAT-enhancer-binding proteins α (C/EBPα) and C/EBPβ which are major regulators of triglyceride synthesis in hepatoma cells. We also found that JRG reduced sterol regulatory element binding proteins 1c (SREBP-1c), C/EBPα and C/EBPβ by regulating liver X receptor (LXR) and stearoyl CoA desaturase (SCD) expressions. In addition, the first-limited step of synthesis triglyceride (TG), glycerol-3-phosphate (G3P) is decreased by JRG. These results suggest that the anti-hypertriglyceride effect of JRG in hepatoma cells could be accompanied with the inhibition of lipidogenic transcription factors by regulating LXR and SCD expression.

• 한국분말재료학회지
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• 제12권1호
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• pp.17-23
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• 2005

Dense $WSi_2$-20vol.%SiC composite was synthesized by high-frequency induction-heated combustion synthesis(HFIHCS) method within 2 minutes in one step from elemental powder mixture of W, Si and C. Simultaneous combustion synthesis and densification were accomplished under the combined effects of an induced current and mechanical pressure. Highly dense $WSi_2$-20vol.%SiC with relative density of up to 97% was produced under simultaneous application of 60MPa pressure and the induced current. The average grain size of $WSi_2$ was about $5.2{\mu}m$. The hardness and fracture toughness values obtained were 1700kg/$mm^2$ and $4.4MPa{\cdot}m^{1/2}$, respectively.

• Archives of Pharmacal Research
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• 제7권2호
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• pp.145-151
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• 1984

A novel agglomeration technique, termed "Spherical Crystallization Process", which can transform directly the fine crystals produced in the crystallization or the reaction process into a spherical shape was developed. By this technique, needle like crystals such as salicylic acid were transformed into free flowing and directly compressible agglomerates. Sphericaly agglomerated aminophyline crystals were obtained directly from the reaction system, which could reduce the preparation processes, e. g. synthesis, crystallization and agglomeration, into only one step. Sodium theophyline monohydrate agglomerates were prepared by salting out, the rate process of which was described by a first order kinetics. Agglomerated crystals of ndw complex of indo-methacin-mepirizole were prepare with this technique; an improved therapeutic effect of the resultant crystals was expected. expected.

• 한국결정학회:학술대회논문집
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• 한국결정학회 2002년도 정기총회 및 추계학술연구발표회
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• pp.27-27
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• 2002

[Cp＊Rh(H₂O)₃](OTf)₂ (1) reacts with a stoichiometric amount of A and B [ A = Me₃SiN₃, B = 4,4'-bipridyl, (2a), A = Me₃SiNCO, B = 4,4'-bipridyl (2b)] in acetone at room temperature for 3 h to give the supramolecular complexes [Cp＊₄Rh₄(μ-A)₄(μ-B)₂] [A = Me₃SiN₃, B = 4,4'-bipridyl, (2a), A = Me₃SiNCO, B = 4,4'-bipridyl (2b)]. Complexes 2a and 2b have been structurally characterized by X-ray diffraction.

• Archives of Pharmacal Research
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• 제29권1호
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• pp.46-49
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• 2006

In this study, 2-N-arylimino-2,3-dihydro-1,3,4-thiadiazoles derivatives (6a-h) were synthetized. The mechanism of the studied reactions was discussed. The chemical structures of the compounds were elucidated by their IR, $^1H-NMR,\;^{13}C-NMR$, and Mass spectral data and elemental analyses. The compounds were tested for antimicrobial activity using diffusion agar technique.

• 대한화학회지
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• 제55권5호
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• pp.787-793
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• 2011

An efficient three-component one-step synthesis of 2,4,5-trisubstituted imidazoles by condensation reaction of 1,2-diketones or ${\alpha}$-hydroxyketones with aromatic aldehydes and ammonium acetate using Zinc (II) [tetra (4-methylphenyl)] porphyrin as a novel and reusable catalyst under ultrasound irradiation at ambient temperature is described. In this method, ${\alpha}$-hydroxyketones as well as 1,2-diketones were converted to their corresponding 2,4,5-trisubstituted imidazoles in excellent yields.

• Bulletin of the Korean Chemical Society
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• 제34권9호
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• pp.2645-2649
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• 2013

We have developed a one-step synthesis of benzofurans from o-iodophenol and various terminal alkynes, by using Pd catalyst supported on nano-sized carbon balls (NCB) under copper- and ligand free conditions. This recyclable catalyst could be reused more than 5 times in the same heteroannulation reaction. The results have demonstrated that diverse 2-substituted benzofurans with tolerant functional groups can be prepared simply and conveniently under these conditions.