• 한국수소및신에너지학회논문집
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• 제28권5호
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• pp.536-544
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• 2017

The effects of catalysts addition on the pyrolysis reaction of biomass have been studied in a thermogravimetric analyzer (TGA). The sample biomasses were Bamboo, Pine and Hinoki. The catalysts tested were K, Zn, Cu metal compounds. The pyrolysis reactions were tested in the nonisothermal condition from the room temperature to $550^{\circ}C$ at a heating rate $50^{\circ}C/min$ on the flowing of $N_2$ purge gases. Cellulose contents of Bamboo was higher than that of Pine and Hinoki. As the results, the pyrolysis reaction of volatile matter was finished near the temperature $450^{\circ}C$. The initial decomposition temperatures of the volatile matters ($T_i$) were $165^{\circ}C$ for Bamboo, $190^{\circ}C$ for Pine, and $193^{\circ}C$ for Hinoki. $T_i$ decreased with increasing the catalyst amounts in the sample biomasses. The temperature of maximum reaction rate ($T_{max}$) were $338^{\circ}C$ for Bamboo, $378^{\circ}C$ for Pine, and $377^{\circ}C$ for Hinoki. The effects of catalysts addition on the $T_{max}$ were to decreased it. The reducing effects about $T_{max}$ was the most effective for K metal compounds catalyst. The char amounts remained after pyrolysis at $550^{\circ}C$ were 26.2% for Bamboo, 20.7% for Pine, and 20.9% for Hinoki. The char amounts increased with the catalyst amounts.

• 한국산림과학회지
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• 제101권3호
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• pp.405-411
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• 2012

경상남도 진주시와 산청군에 위치한 성숙한 밤나무 재배지를 대상으로 여러 가지 토양 개량제 처리[(유기질비료 처리구: 20 kg/본; 복합비료 및 목탄 처리구: 복합비료 4 kg/본+목탄 2 kg/본; 석회비료 처리구: 3 kg/본; 혼합비료 처리구: 복합비료 1 kg/본+유기질비료 10 kg/본+목탄 1 kg/본; 대조구(무시비구)]가 토양 특성 및 잎 형질에 미치는 단기적 영향을 조사하였다. 밤나무 재배지에 토양용적밀도, 토양 유기탄소, 전 질소, 칼슘 및 마그네슘 함량은 양 개량제 처리에 따른 유의적인 변화가 없었다. 그러나 잎 건중량은 진주지역 석회비료 처리구($0.65\;g\;leaf^{-1}$), 산청지역 유기질비료 처리구($0.68\;g\;leaf^{-1}$)로 대조구(진주: $0.46\;g\;leaf^{-1}$; 산청: $0.53\;g\;leaf^{-1}$)에 비해 유의적으로 높았다. 잎면적의 경우 진주지역 석회비료 처리구가($79.1\;cm^2\;leaf^{-1}$)로 가장 크게 나타났으며, 산청지역 토양 개량제 처리구는 ($70.4\;cm^2\;leaf^{-1}{\sim}78.2\;cm^2\;leaf^{-1}$)로 대조구(진주: $56.2\;cm^2\;leaf^{-1}$; 산청: $60.5\;cm^2\;leaf^{-1}$)에 비해 유의적으로 증가하였다. 토양 개량제 처리에 따른 잎 내 질소 함량은 혼합비료 처리구가 2.51%, 복합비료+목탄 처리구가 2.50%로 대조구 .98%에 비해 유의적으로 높았다. 본 연구 결과에 따르면 토양 개량제 처리는 밤나무 재배지의 단기적인 토양 특성개선에는 효과가 크지 않았으나 잎 형질 개선에 효과가 있었으며, 잎 내 질소 분석은 밤나무 재배지의 토양 개량 효과를 판정할 수 있는 지표로 나타났다.

• Korean Chemical Engineering Research
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• 제48권1호
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• pp.58-67
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• 2010

본 연구에서는 국내 상용 순환유동층 보일러에서 연료로 사용하고 있는 저급 국내무연탄과 혼소용 연료로 이용할 예정인 목재펠릿의 각각의 연소 특성을 조사하기 위해 열중량 분석기(TGA)를 이용하여 비등온 실험(5, 10, 20, $30^{\circ}C/min$) 및 등온 조건으로 촤 연소 실험을 수행하였다. 목재펠릿의 경우는 승온 속도에 따라 차이가 있으나, 국내무연탄에 비해 낮은 온도인 $200{\sim}620^{\circ}C$ 사이에서 연소되었으며, 최대 반응속도를 나타내는 온도 또한 국내무연탄의 그것에 비해 매우 낮음을 알 수 있었다. 비등온 실험 결과를 Friedman 방법으로 해석한 결과, 무게감량이 가장 큰 2차 구간에서의 목재펠릿 및 국내무연탄의 활성화에너지는 44.12, 21.45 kcal/mol이었으며, 반응차수 및 빈도인자는 각각 5.153, 0.7453 및 $4.01{\times}10^{16}$, $1.39{\times}10^6(s^{-1})$임을 확인할 수 있었다. 또한 등온 조건으로 촤 연소 실험 결과, 화학반응 율속단계에서의 목재펠릿 및 국내무연탄의 활성화에너지는 각각 27.5, 51.2 kcal/mol이었으며, 빈도인자는 각각 $2.55{\times}10^{12}$, $1.49{\times}10^{10}(s^{-1})$임을 확인할 수 있었다. 국내무연탄에 비해 목재펠릿이 낮은 온도에서 연소 반응이 시작이 되고 반응차수 및 빈도인자가 높아 반응속도를 빠를 것으로 판단되어 혼소 시 연소 제어가 잘 이루어질 경우, 연소로 내의 연소 분위기가 향상될 것으로 예상된다.

• 한국안전학회지
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• 제24권6호
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• pp.63-71
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• 2009

In order to improve flame retardancy, the halogen free organic melamine phosphate(M-P) flame retardant was synthesized from melamine and phosphoric acid by the reaction of precipitation. The ignition test was carried out preparing hybrid flame retardant compound($H_bFRC$) consisting of organic M-P and inorganic Mg$(OH)_2$ as a flame retardant in the polyolefin resins. The flame retardancy and mechanical properties of flame retardant aluminum composite panel($H_bFRC$-ACP) were performed to investigate the possibility of the composite material, which was contained M-P, as a inner core for $H_bFRC$-ACP. For this study, the results of ignition test indicate that a char formation and drip suppressing effect, and combustion time reduced as the content of M-P increased. The limited oxygen index(LOI) values were measured 17.4vol% and 31.5vol% for LDPE only and $H_bFRC$-3(M-P content: 15wt%), respectively. And it was verified that the $H_bFRC$-3 was needed more oxygen quantity with the increase of M-P content when it combustion. Also, the results from thermogravimetric analysis were observed endothermic peak at $350^{\circ}C$ and $550^{\circ}C$, it was confirmed predominant thermal stability though the wide temperature range by the mixture of M-P and Mg$(OH)_2$. The LDPE-ACP (using only LDPE as a inner core), $35.13kW/m^2$ of heat release rate(HRR) and 13.43MJ/m2 of total heat release(THR) were measured while the $H_bFRC$-ACP, $10.44kW/m^2$ of HRR and 1.84MJ/m2 of THR were measured by results of cone calorimeter test. In case of $H_bFRC$-ACP, the average gas emission amount of CO and $CO_2$ could be decreased down to 25% and 20%, respectively, in comparison with LDPE-ACP. The mechanical properties such as tensile strength, bending strength and adhesion strength of $H_bFRC$-ACP were revealed slightly high values $54N/mm^2$, $152N/mm^2$ and 120N/25mm, respectively, compared with LDPE-ACP. It was confirmed that flame retardancy was improved with the synergy effect because of char formation by M-P and hydrolysis by Mg$(OH)_2$. The result of this study suggest that $H_bFRC$ can be applied for an adequate halogen free flame retardant composite material as a inner core for ACP.

• Carbon letters
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• 제4권3호
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• pp.126-132
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• 2003

Granular Activated Carbon (GAC) has been proven to be an excellent material for many industrial applications. A systematic study has been carried out of the kinetics of physical as well as chemical activation of phenolic resin chars. Physical activation was carried out using $CO_2$ and chemical activation using KOH as activating agent. There are number of factors which influence the rate of activation. The activation temperature and residence time at HTT varied in the range $550{\sim}1000^{\circ}C$ and $\frac{1}{2}{\sim}8$ hrs respectively. Kinetic studies show that the rate of chemical activation is 10 times faster than physical activation even at much lower temperature. Above study show that the chemical activation process is suitable to prepare granular activated carbon with very high surface area i.e.$ 2895\;m^2/g$ in short duration of time i.e. 1 to 2 hrs at lower temperature i.e. $750^{\circ}C$ from phenolic resins.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.282-282
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• 2006

Nanoporous organosilicate thin films were realized by the microphase separation of pore generating components mixed with an organosilicate matrix. The refractive index of such nanoporous organosilicate films can be tuned in the range of $1.40{\sim}1.22$. With a nanoporous single layer with n ${\sim}1.225,\;99.85\;%$ transmittance in the visible range was achieved. In order to overcome the limitation on the narrow wavelength for high transmittance imposed by single nanoporous thin films, bilayer thin films with different reflectance for each layer were prepared by inserting high refractive index layer with a refractive index of 1.447. It is demonstrated that the novel broadband antireflection coating with improved transmittance can be easily achieved by the nanoporous bilayer thin films described in present study.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.307-307
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• 2006

The reduction behavior of silver ions to silver nanoparticles is an important research topic in polymer/silver salt complex membranes for facilitated olefin transport, because it has a significant effect on the long-term stability of membrane performance. In this study, the effects of solvent on the formation of silver nanoparticles and long-term membrane performance in polymer/silver salt complex membrane were investigated. This effect was assessed for the complexes of poly(N-vinyl pyrrolidone) $(PVP)/AgBF_{4}$ with the use of ionic liquid (IL), acetonitrile (ACN) and water as a solvent. Membrane performance test shows that long-term stability is strongly dependent on the kind of solvent and arranged: IL > ACN >> water.

• 한국염색가공학회지
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• 제20권4호
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• pp.1-7
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• 2008

Methacryloxypropyl trimethoxysilane (MAPTMS), a hybrid organic-inorganic monomer, was photografted onto PET fabric using benzophenone (BP) as a photoinitiator. It was found that a UV energy of 43.2J/$cm^2$ was required to optimally photograft the MAPTMS onto PET fabrics which was applied with an aqueous formulation of 10% MAPTMS, 20% BP and 0.5% N-Methyldiethanol amine (MDEA). The MDEA additive was efficient in reducing atmospheric oxygen inhibition of polymer radicals which eliminated compulsory nitrogen inerting. The surface grafting of PET fabrics was verified by fourier transform infrared spectroscopy (FT-IR) and scanning electron spectroscopy (SEM). The grafted PET fabrics with the hybrid monomer showed higher thermal stability due to the introduced silane component in the monomer as ascertained by higher char content at 800$^{\circ}C$, which increased to 14.5% for the 15.8% grafting compared to 8.2% for the untreated.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2003년도 유체기계 연구개발 발표회 논문집
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• pp.541-546
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• 2003

Activated carbon was prepared from coffee wastes by chemical activation with $ZnCl_{2}$, NaOH and KOH. The coffee wastes was used as raw material. Preparation process involves the roasting of raw material and carbonization of roasted material followed by chemical activation. N2-BET surface areas of activated coffee char prepared by chemical activation was measured as $1,110{\sim}2,442m^{2}/g$. Removal of copper and chromium in solution by activated carbon was carried out and structural change of pore surface was observed by SEM.

• Macromolecular Research
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• 제17권11호
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• pp.901-906
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• 2009

Several aromatic optically active polyamides (PA)s were synthesized from 5-(2-phthalimidiylpropanoylamino)isophthalic acid with various aromatic diamines via direct polycondensation with triphenyl phosphite and pyridine in the presence of calcium chloride and N-methyl-2-pyrrolidone under microwave irradiation and conventional heating conditions. Under the optimized conditions, the reaction mixture was irradiated for 2 min. with a 100% irradiation power (900 W). The resulting polymers were obtained in high yield and moderate inherent viscosity ranging from 0.35 to 0.60 dL/g. All synthesized polymers showed excellent solubility in amide-type solvents. Thermogravimetric analysis revealed a 10% weight loss temperature and char yield at $600^{\circ}C$ in a nitrogen atmosphere of > $350^{\circ}C$ and > 58%, respectively, which suggests that the resulting PAs have good thermal stability.