• 제목/요약/키워드: bombardment

검색결과 406건 처리시간 0.038초

길경(Platycodi Radix) Butanol 분획물의 항염증 활성 성분 (Anti-Inflammatory Components of Platycodi Radix Butanol Fractions)

  • 김성연;이은방;정은자
    • 동아시아식생활학회지
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    • 제22권6호
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    • pp.772-781
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    • 2012
  • This study was conducted to examine the development of a new anti-inflammatory substance with potent anti-inflammatory activities that was derived from the Platycodi Radix butanol fraction. To accomplish this, the chemical structures and anti-inflammatory activities of the components were elucidated. Upon column chromatography of the tertiary subfraction, fractions 8-4-1 and 8-4-2 were identified as platycodin D and D3, respectively, following recrystallization, based on melting point (MP), infrared (IR), and positive fast atom bombardment (FAB)-mass and nuclear magnetic resonance (NMR) spectral data. Platycodin D and D3 exhibited strong anti-inflammatory activities in rats when administerd at oral doses of 12 mg/kg and 36 mg/kg, p.o., respectively. Platycodin D and D3 induced inhibitory effects on capillary vascular permeability in rats at oral doses of 16 mg/kg and 24 mg/kg, p.o., respectively, and potent inhibition of leukocyte emigration in a carboxymethyl cellulose (CMC)-pouch when administered at doses of 3 mg/rat and 7 mg/rat, s.c., respectively. These results verified the high antiinflammatory potency of the platycodin D and D3 components in Platycodi Radix.

Structural Analyses of the Novel Phosphoglycolopids Containing the Unusual very Long Bifunctional Acyl Chain, α,ω-13,16-Dimethyloctacosanedioate in Thermoanaerobacter ethanolicus

  • Lee, Sang-Hoo;Kang, Se-Byung;Kim, Jai-Neung;Jung, Seun-Ho
    • Bulletin of the Korean Chemical Society
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    • 제23권12호
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    • pp.1778-1784
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    • 2002
  • Novel membrane lipids containing the unusual very long chain fatty $acid{\alpha}{\omega}-1316-dimethyloctacosanedioate$, dimethyl. Ester (DME C30) was isolated and purified from thermophilic anaerobic eubacterium, Thermoanaerobacter ethanolicus. Structures of the lipids containing the bifunctional fatty acyl components were proposed by various analyses such as $^1H,\;^{13}C,\;^{31}P$ nuclear magnetic resonance (NMR), Fourier transform infrared(FTIR) spectroscopy, gas chromatography/mass spectrometry (GC/MS) and fast atom bombardment mass spectrometry (FAB/MS). Combined with the GC/MS, $^1H,\;and\;^{13}C$NMR data, we confirmed that the head groups of the lipids contained the glycerol and/or glucosamine molecules. $^{31}P$ NMR spectrum also showed that the lipids contained phosphate in a phosphodiester linkage. The proposed structures of these novel lipid components were the ones in which two head groups were linked by the membrane spanning fatty acyl component(DME C30)and regular chain fatty acids on glycerol moiety of each head group.

낮은 에너지로 실리콘에 이온 주입된 분포와 열처리된 인듐의 거동에 관한 시뮬레이션과 모델링 (Modeling and Simulation on Ion Implanted and Annealed Indium Distribution in Silicon Using Low Energy Bombardment)

  • 정원채
    • 한국전기전자재료학회논문지
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    • 제29권12호
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    • pp.750-758
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    • 2016
  • For the channel doping of shallow junction and retrograde well formation in CMOS, indium can be implanted in silicon. The retrograde doping profiles can serve the needs of channel engineering in deep MOS devices for punch-through suppression and threshold voltage control. Indium is heavier element than B, $BF_2$ and Ga ions. It also has low coefficient of diffusion at high temperatures. Indium ions can be cause the erode of wafer surface during the implantation process due to sputtering. For the ultra shallow junction, indium ions can be implanted for p-doping in silicon. UT-MARLOWE and SRIM as Monte carlo ion-implant models have been developed for indium implantation into single crystal and amorphous silicon, respectively. An analytical tool was used to carry out for the annealing process from the extracted simulation data. For the 1D (one-dimensional) and 2D (two-dimensional) diffused profiles, the analytical model is also developed a simulation program with $C^{{+}{+}}$ code. It is very useful to simulate the indium profiles in implanted and annealed silicon autonomously. The fundamental ion-solid interactions and sputtering effects of ion implantation are discussed and explained using SRIM and T-dyn programs. The exact control of indium doping profiles can be suggested as a future technology for the extreme shallow junction in the fabrication process of integrated circuits.

Twin Target Sputtering System with Ladder Type Magnet Array for Direct Al Cathode Sputtering on Organic Light Emitting Diodes

  • Moon, Jong-Min;Kim, Han-Ki
    • Journal of Information Display
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    • 제8권3호
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    • pp.5-10
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    • 2007
  • Twin target sputtering (TTS) system with a configuration of vertically parallel facing Al targets and a substrate holder perpendicular to the Al target plane has been designed to realize a direct Al cathode sputtering on organic light emitting diodes (OLEDs). The TTS system has a linear twin target gun with ladder type magnet array for effective and uniform confinement of high density plasma. It is shown that OLEDs with Al cathode deposited by the TTS show a relatvely lower leakage current density $({\sim}1{\times}10^{-5}mA/cm^2)$ at reverse bias of -6V, compared to that ($1{\times}10^{-2}{\sim}10^{-3}$ $mA/cm^2$ at -6V) of OLEDs with Al cathodes grown by conventional DC magnetron sputtering. In addition, it was found that Al cathode films prepared by TTS were amorphous structure with nanocrystallines due to low substrate temperature. This demonstrates that there is no plasma damage caused by the bombardment of energetic particles. This indicates that the TTS system with ladder type magnet array could be useful plasma damage free deposition technique for direct Al cathode sputtering on OLEDs or flexible OLEDs.

THE FABRICATION OF A PROCESS HEAT EXCHANGER FOR A SO3 DECOMPOSER USING SURFACE-MODIFIED HASTELLOY X MATERIALS

  • Park, Jae-Won;Kim, Hyung-Jin;Kim, Yong-Wan
    • Nuclear Engineering and Technology
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    • 제40권3호
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    • pp.233-238
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    • 2008
  • This study investigates the surface modification of a Hastelloy X plate and diffusion bonding in the assembly of surface modified plates. These types of plates are involved in the key processes in the fabrication of a process heat exchanger (PHE) for a $SO_3$ decomposer. Strong adhesion of a SiC film deposited onto Hastelloy X can be achieved by a thin SiC film deposition and a subsequent N ion beam bombardment followed by an additional deposition of a thicker film that prevents the Hastelloy X surface from becoming exposed to a corrosive environment through the pores. This process not only produces higher corrosion resistance as proved by electrolytic etching but also exhibits higher endurance against thermal stress above 9$900^{\circ}C$. A process for a good bonding between Hastelloy X sheets, which is essential for a good heat exchanger, was developed by diffusion bonding. The diffusion bonding was done by mechanically clamping the sheets under a heat treatment at $900^{\circ}C$. When the clamping jig consisted of materials with a thermal expansion coefficient that was equal to or less than that of the Hastelloy X, sound bonding was achieved.

Ionized Cluster Beam 증착방법을 이용한 Indium-Tin-Oxide(ITO) 박막의 제작과 그 특성에 관한 연구 (A Study on the Fabrication and Characteristics of ITO thin Film Deposited by the Ionized Cluster Beam Deposition)

  • 최성창;황보상우;조만호;김남영;홍창의;이덕형;심태언;황정남
    • 한국진공학회지
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    • 제5권1호
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    • pp.54-61
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    • 1996
  • Indium-tin oxide (ITO) films were deposited on the glass substrate by the reactive -ionized cluster beam deposition(ICBD) method. In the oxygen atmosphere, indium cluster formed through the nozzle is ionized by the electron bombardment and is accelerated to be deposited on the substrate. And tin is simultaneoulsy evaporated from the boron-nitride crucible. The chracteristics of films were examined by the X-ray photoelectron spectroscopy(XPS), glancing angle X-ray diffractrion(GXRD) and the electrical properties. were measured by 4-point-probe and Hall effect measurement system . From the XPS spectrum , it was found that indium and tin atoms combined with the oxygen to form oxide$(In_2O_3, SnO_2)$. In the case of films with high tin-concentration, the GXRD spectra show that the main $In_2O_3$ peak of (222) plane, but also sub peaks((440) peak etc.) and $SnO_2$ peaks were detected. From that results, itis concluded that the heavily dopped tin component (more than 14 at. %) disturbs to form $In_2O_3$(222) phase. Four-point-probe and Hall effect measurement show that, in the most desirable case, the transmittance of the films is more then 90% in visible range and its resistivity is $$\rho$=3.55 \times10^{-4}\Omega$cm and its mobility is $\mu$=42.8 $\textrm{cm}^2$/Vsec.

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D.C. 마그네트론 반응성 스퍼터링법에 의한 Sn-doped ${In_2}{O_3}$ 박막의 밀도와 전기적 특성과의 관계 (Relationship between Film Density and Electrical Properties on D.C. Magnetron Reactive Sputtered Sn-doped ${In_2}{O_3}$Films)

  • 이정일;최시경
    • 한국세라믹학회지
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    • 제37권7호
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    • pp.686-692
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    • 2000
  • Tin-doped In2O3 (ITO) films were fabricated using a d.c. magnetron reactive sputteirng of a In-10 wt% Sn alloy target in an Ar and O2 gas mixture. To understand the behavior of the carrier mobility in ITO films with O2 partial pressure, the resistivity, carrier concentration and mobility, film density, and intrinsic stress in the films were measured with O2 partial pressure. It was found experimentally that the carrier mobility increased rapidly as the film density increased. In the ITO film with the density close to theoretical one, the mean free path was the same as the columnar diameter. This indicated that the mobility in ITO films was strongly influenced by the crystall size. However, in the case where the film density was smaller than a theoretical density, the mean free paths were also smaller the columnar diameter. It was analyzed that the electron scattering at pores and holes within the crystalline was the major obstacle for electron conduction in ITO films. The measurement of intrinsic stress in ITO films also made it clear that the density of ITO films was controlled by the bombardment of oxygen neutrals on the growing film.

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유도결합 플라즈마를 이용한 마그네트론 스퍼터링으로 증착된 나노결정질 CrN 코팅막의 성장 (Growth Behavior of Nanocrystalline CrN Coatings by Inductively Coupled Plasma (ICP) Assisted Magnetron Sputtering)

  • 서대한;전성용
    • 한국세라믹학회지
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    • 제49권6호
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    • pp.556-560
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    • 2012
  • Nanocrystalline CrN coatings were deposited by DC and ICP-assisted magnetron sputtering on Si (100) substrates. The influences of the ICP power on the microstructural and crystallographic properties of the coatings were investigated. For the generation of the ICP, radio frequency was applied using a dielectric-encapsulated coil antenna installed inside the deposition chamber. As the ICP power increased from 0 to 500W, the crystalline grain size decreased. It is believed that the decrease in the crystal grain size at higher ICP powers is due to resputtering of the coatings as a result of ion bombardment as well as film densification. The preferential orientation of CrN coatings changed from (111) to (200) with an increase in the ICP power. The ICP magnetron sputtering CrN coatings showed excellent surface roughness compared to the DC magnetron sputtering coatings.

Ar/CF$_4$/Cl$_2$ 플라즈마에 의한 CeO$_2$ 박막의 식각 특성 연구 (A study on etch Characteristics of CeO$_2$ thin Film in an Ar/CF/C1$_2$ Plasma)

  • 장윤성;장의구;김창일;이철인;김태형;엄준철
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집
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    • pp.217-220
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    • 2001
  • The possibility of cerium dioxide (CeO$_{7}$ ) thin films as insulators of metal erroelectric insulator semiconductor (MFIS) structures have been studied. The etching CeO$_2$ thin films have been performed in an inductively coupled C1$_2$/CF$_4$/Ar plasma. The high etch rate of the CeO$_2$ thin film was 250 ${\AA}$/m at a 10% addition of Cl$_2$ into the Ar(80)/CF$_4$(20). The surface reaction of the etched CeO$_2$ thin films was investigated using X-ray photoelectron spectroscopy (XPS) analysis. There are Ce-Cl and Ce-F bonding by chemical reaction between Cl, F and Ce. These products can be removed by the physical bombardment of incident Ar ions.

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유도 결합 플라즈마($Cl_2$/Ar)를 이용한 $CeO_2$ 박막의 식각 특성 연구 (A Study on the Etching Characteristics of $CeO_2$ Thin Films using inductively coupled $Cl_2$/Ar Plasma)

  • 오창석;김창일;권광호
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 추계학술대회 논문집
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    • pp.29-32
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    • 2000
  • Cerium oxide thin film has been proposed as a buffer layer between the ferroelectric film and the Si substrate in Metal-Ferroelectric-Insulator-Silicon (MFIS ) structures for ferroelectric random access memory (FRAM) applications. In this study, CeO$_2$ thin films were etched with Cl$_2$/Ar gas combination in an inductively coupled plasma (ICP). The highest etch rate of CeO$_2$ film is 230 $\AA$/min at Cl$_2$/(Cl$_2$+Ar) gas mixing ratio of 0.2. This result confirms that CeO$_2$ thin film is dominantly etched by Ar ions bombardment and is assisted by chemical reaction of Cl radicals. The selectivity of CeO$_2$ to YMnO$_3$ was 1.83. As a XPS analysis, the surface of etched CeO$_2$ thin films was existed in Ce-Cl bond by chemical reaction between Ce and Cl. The results of XPS analysis were confirmed by SIMS analysis. The existence of Ce-Cl bonding was proven at 176.15 (a.m.u.).

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