• 한국대기환경학회지
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• 제23권5호
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• pp.575-584
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• 2007

The adsorption capability of iron phthalocyanine derivatives were investigated by means of X-ray diffractometor (XRD), IR (infrared) spectroscopy, scanning electron microscopy (SEM) and temperature programmed desorption (TPD). According to TPD results, iron phthalocyanine derivatives showed two desorption peaks at low temperature ($100{\sim}150^{\circ}C$) and high temperature ($350{\sim}400^{\circ}C$) indicating that there were two kinds of acidities. Tetracarboxylic iron phthalocyanine (Fe-TCPC) have a stronger desorption peak (chemical adsorption) at the high temperature and a weaker desorption peak (physical adsorption) at the low temperature than iron phthalocyanine (Fe-PC). The specific surface areas of Fe-TCPC and Fe-PC were $26.46\;m^2/g\;and\;11.77\;m^2/g$, respectively. The pore volumes of Fe-TCPC and Fe-PC were $0.14\;cm^3/g\;and\;0.06\;cm^3/g$, respectively. The adsorption capability of triethyl amine calculated by breakthrough curve at 220 ppm of equilibrium concentration was 29.2 mmoL/g for Fe-TCPC and 0.8 mmoL/g for Fe-PC. The removal efficiency of dimethyl sulfide of Fe-TCPC and Fe-PC in batch experiment of 225 ppm of initial concentration were 44.9% and 28.9%, respectively. The removal efficiency of trimethyl amine of Fe-TCPC and Fe-PC in batch experiment of 118 ppm of initial concentration were approximately 100.0% and 33.9%, respectively.

• 폴리머
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• 제28권2호
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• pp.194-200
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• 2004

돼지의 소장 점막하 조직은 면역반응이 없는 재료로 널리 사용되고 있다. 본 연구에서는 소장 점막하 조직을 1-ethyl-(3,3-dimethyl aminopropyl) carboimide hydrochloride(EDC)를 이용하여 경화시켰으며 동시에 스폰지 형태로 제조하여 조직공학적 담체와 상처 드레싱재료로서의 응용 가능성을 검토하였다. 다세포 구성분을 제거한 소장 점막하 조직 분말을 3% 아세트산에 용해하여 일정한 형태의 몰드 내에 붓고 동결 건조하였다 이 소장 점막하 조직 스폰지를 여러 농도의 EDC용액에 침지하여 가교반응을 실시하였다 이를 전자주사 현미경, 시차 주사열량계, 적외선 분광분석기, 다공도 테스트 및 흡수성 실험을 수행하여 특성을 결정하였다. 소장 점막하 조직 스폰지는 경화제의 농도가 50mM 이상에서 물리적 특성이 우수한 것으로 판단되었다. 일련의 실험을 통하여 경화된 소장 점막하 조직 스폰지가 조직공학적 담체와 상처치료 드레싱재료로 유용하게 사용될 수 있음을 확인하였다.

• 한국재료학회지
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• 제9권8호
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• pp.825-830
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• 1999

FTES/$O_2$-PECVD 방법에 의하여 증착된 SiOF 박막의 특성을 FT-IR, SPS, 그리고 ellipsometry로 분석하였다. 유전상수, breakdown field와 누설전류 밀도는 MIS(Au/SiOF/p-Si) 구조로 형성하여 C-V와 I-V특성곡선으로부터 측정하였다. SiOF박막의 step-coverage는 SEM 단면사진으로 조사하였다. FTES와 $O_2$의 유량을 각각 300sccm으로 반응로에 주입하였을 때 양질의 SiOF 박막이 형성되었다. 형성된 박막의 유전상수는 3.1로서 다른 산화막보다 더 낮은 값으로 나타났다. breakdown field와 누설전류밀도는 약 10MV/cm와 $8{\times}10^{9}A/\textrm{cm}^2$로 측정되었다. $0.3{\mu}{\textrm}{m}$ 금속 패턴에 $2500{\AA}$의 두께로 증착된 SiOF 박막은 전극간에 void가 없이 우수한 덮힘을 보였다.

• 한국재료학회지
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• 제8권9호
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• pp.865-870
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• 1998

생체내에서 매식되는 타이타늄의 표면에 골의 형성과 성장을 촉진시키기 위해 칼슘이온과 인산이온을 함유하는 용액에서 타이타늄의 표면처리를 행하였다. 표면처리방법으로는 pH 5.8, 7.0, 8.0의 인산칼슘 완충용액에 10분간 침적시킨 후 유사체액에 30일간 침적시켰다. 침적시킨 후의 타이타늄 표면에 형성된 피막의 특성을 주사전자현미경, X-ray 회절장치, Fourier 변환강도계등으로 확인하고 유사체액에만 침적한 시편의 표면특성과 비교하였다. 실험결과 인산완충용액에서의 침적에 의해 타니타늄 표면에 인산칼슘 형성이 촉진됨을 알 수 있었다. 형성된 층은 입자형의 미세구조를 지닌 하이드록시아파타이트나 $\beta$-TCP의 인산칼슘 층으로 확인되었다. 형성된 층의두께는 pH 8.0, 7.0 그리고 pH 5.8의 인산완충액에서의 침적 순으로 증가하였고, 그 밀도는 pH 7.0, pH8.0그리고 pH5.8의 인산완충액에서의 침적 순으로 증가하였다.

• 한국표면공학회지
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• 제46권4호
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• pp.139-144
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• 2013

c-BN(cubic boron nitride) is known to have extremely high hardness next to diamond, as well as very high thermal and chemical stability. The c-BN in the form of film is useful for wear resistant coatings where the application of diamond film is restricted. However, there is less practical application because of difficult control of processing variables for synthesis of c-BN film as well as unclear mechanism on formation of c-BN. Therefore, in the present study, the structural characterization of c-BN thin film were investigated using $B_4C$ target in r.f. magnetron sputtering system as a function of processing variables. c-BN films were coated on Si(100) substrate using $B_4C$ (99.5% purity). The mixture of nitrogen and argon was used for carrier gas. The deposition processing conditions were changed with substrate bias voltage, substrate temperature and base pressure. Fourier transform infrared microscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) were used to analyze crystal structures and chemical binding energy of the films. In the case of the BN film deposited at room temperature, c-BN was formed in the substrate bias voltage range of -400 V~ -600 V. Less c-BN fraction was observed as deposition temperature increased and more c-BN fraction was observed as base pressure increased.

• 한국표면공학회지
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• 제51권2호
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• pp.126-132
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• 2018

SnS thin films with different substrate temperatures ($150 {\sim}300^{\circ}C$) as process parameters were grown on soda-lime glass substrates by RF magnetron sputtering. The effects of substrate temperature on the structural and optical properties of SnS thin films were investigated by X-ray diffraction (XRD), Raman spectroscopy (Raman), field-emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), and Ultraviolet-visible-near infrared spectrophotometer (UV-Vis-NIR). All of the SnS thin films prepared at various substrate temperatures were polycrystalline orthorhombic structures with (111) planes preferentially oriented. The diffraction intensity of the (111) plane and the crystallite size were improved with increasing substrate temperature. The three major peaks (189, 222, $289cm^{-1}$) identified in Raman were exactly the same as the Raman spectra of monocrystalline SnS. From the XRD and Raman results, it was confirmed that all of the SnS thin films were formed into a single SnS phase without impurity phases such as $SnS_2$ and $Sn_2S_3$. In the optical transmittance spectrum, the critical wavelength of the absorption edge shifted to the long wavelength region as the substrate temperature increased. The optical bandgap was 1.67 eV at the substrate temperature of $150^{\circ}C$, 1.57 eV at $200^{\circ}C$, 1.50 eV at $250^{\circ}C$, and 1.44 eV at $300^{\circ}C$.

• 자원환경지질
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• 제15권4호
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• pp.189-204
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• 1982

The Geodo mine is located in the southern limb of the Hambaeg syncline. Geology of the area consists of Paleozoic-Mesozoic sedimentary Rocks and Cretaceous igneous rocks. The important igneous rocks presumably related to skarnization and ore mineralization in the area, are the early granodiorite and the late porphyritic granodiorite. Two mineralogical types of ore deposits are recognized in the area. They are the Fe-Cu deposits in the Myobong formation and the Au-Bi-Cu deposits in the Hwajeol formation. Contact metamorphism due to granodiorite intrusion includes hornfelsization, exoskarnization and endoskarnization. Wall-rock alterations related to the Fe mineralization are grouped into the hydrothermal replacement skarnization and the hydrothermal filling skarnization. Another hydrothermal alteration is associated with the Cu mineralization. Various mineralogical analyses have been applied for the identification of minerals. They include optical microscopy, chemical analysis, etching test, X-ray diffraction, and infrared absorption spectroscopic analyses. The ore minerals in these ore deposits are classified into two groups;hypogene and supergene minerals. Hypogene minerals consist of magnetite, pyrite, chalcopyrite, and chalcocite. Supergene minerals consist of chalcocite, bornite, and geothite. Ore minerals show various kinds of ore texture: open-space filling, exsolution, replacement, and cementation texture. The gangue minerals consist of quartz, diopside, epidote, garnet and plagioclase in the hornfelsic zone, garnet, diopside, scapolite, actinolite, sericite, chlorite, quartz, and calcite in the skarn zone, and, epidote, chlorite, sericite, quartz, and calcite in the late hydrothermal alteration zone. This study shows that the Fe-Cu deposits are of metasomatic pipe type with the later hydrothermal fillings, and the Au-Bi-Cu deposits are of hydrothermal fissure-filling type. The mineralization is probably related to the intrusion of porphyritic granite.

• Journal of Biosystems Engineering
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• 제39권3호
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• pp.235-243
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• 2014

Purpose: The aim of this study was to prepare and evaluate a natural material extracted from germinated brown rice (GBR). Herein, we evaluated whether the natural material could positively activate the biological effects seen during bone formation, including enhancement of metabolic activity, osteogenesis, and the expression of vascular endothelial growth factor (VEGF), one of the growth factors in human osteoblast-like cells. Methods: The natural material was created by a hot water extraction process after being soaked for 2~3 days in tap water and dried at $50^{\circ}C$. The material was characterized using field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Fourier transformed infrared (FTIR) spectroscopy. The biological behaviors of the material were also investigated; we performed tests to assess cell cytotoxicity, metabolic activity, osteogenic markers related to bone formation, and VEGF. Results: The EDX, XRD, and FTIR results for the natural material indicated the presence of organic compounds. The natural material caused positive increases in cell metabolic activity and mineralized bone formation without cytotoxicity. The protein levels in the extract for the $6.25{\mu}g/mL$, $12.25{\mu}g/mL$, $25{\mu}g/mL$, $50{\mu}g/mL$, and $100{\mu}g/mL$ groups were significantly different from that for the control. Conclusions: The GBR-based natural material was easy to prepare and had characteristics of a potential biomaterial. The biocompatibility of this natural material was evaluated using in vitro techniques; our findings indicate that this novel material is promising for agricultural and biological applications.

• 한국환경과학회지
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• 제25권12호
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• pp.1613-1622
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• 2016

Zeolite (FZ), prepared from fly ash, was immobilized with polyacrylonitrile (PAN) to fabricate PAN/FZ beads. The prepared PAN/FZ beads were characterized by scanning electron microscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy. The optimum ratio to prepare PAN/FZ beads was 0.3 g of PAN to 0.3 g of FZ. The diameter of the prepared PAN/FZ beads was about 3 mm. Sr and Cu ion adsorption experiments were conducted with PAN/FZ beads. A pseudo-second-order model fit the kinetic data for Sr and Cu ion adsorption by PAN/FZ beads well. The equilibrium data fitted well with the Langmuir isotherm model, and the maximum adsorption capacities were 96.5 mg/g and 74.6 mg/g for the Sr and Cu ions, respectively. Additionally, the values of thermodynamic parameters such as Gibbs free energy (${\Delta}G^o$), enthalpy (${\Delta}H^o$) and entropy (${\Delta}S^o$) were determined. The positive values of ${\Delta}H^o$ revealed the endothermic nature of the adsorption process and the negative values of ${\Delta}G^o$ were indicative of the spontaneity of the adsorption process.

• 한국환경과학회지
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• 제25권12호
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• pp.1623-1632
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• 2016

Zeolite (FZ) prepared using coal fly ash from an Ulsan industrial complex was immobilized with polysulfone (PS) to fabricate PS-FZ beads. The prepared PS-FZ beads were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. The optimum ratio for preparing PS-FZ beads was 1 g of PS to 2 g of FZ. The removal efficiencies of Sr and Cu ions by the PS-FZ beads increased as the solution pH increased and nearly reached a plateau at pH 4. A pseudo-second-order model morel fit the adsorption kinetics of both ions by the PS-FZ beads better than a pseudo-first-order model. The Langmuir isotherm model fit the equilibrium data well. The maximum adsorption capacities calculated from the Langmuir isotherm model were 46.73 mg/g and 62.54 mg/g for the Sr and Cu ions, respectively. Additionally, the values of thermodynamic parameters such as free energy (${\Delta}G^{\circ}$), enthalpy (${\Delta}H^{\circ}$) and entropy (${\Delta}S^{\circ}$) were determined. The results implied that the prepared PS-FZ beads could be interesting an alternative material for Sr and Cu ion removal.