• Title/Summary/Keyword: 3C120

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Kinetics of Ethyl Phenylcarbamate Synthesis by the Oxidative Carbonylation of Aniline (아닐린의 산화적 카르보닐화에 의한 에틸페닐카바메이트의 합성의 속도론적 고찰)

  • Park, Nae-Joung;Park, Jae-Keun
    • Applied Chemistry for Engineering
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    • v.3 no.4
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    • pp.710-716
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    • 1992
  • Ethylphenyl carbarmate(EPC) was synthesized by oxidative CO carbonylation of aniline in the presence of transition metal catalysts and alkali metal halide cocatalysts at $120^{\circ}C$ under the pressure of 79atm. Oxygen gas was used for oxidizing agent. Kinetics of the reaction was studied and activation energies with different catalysts were estimated. About 100% conversion to EPC and 95% selectivity was obtained in 5 hour reaction. 5% Pd/C was more effective than 5% Rh/C. Effectiveness of cocatalysts was in the order of KI>KBr>KCl. As the temperature increased from $75^{\circ}C$ to $120^{\circ}C$, the conversion rate increased. The reaction was apparent first order and the activation energies with 5% Pd/C and 5% Rh/C were 5.647 and 5.780 kcal/mol, respectively.

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A Study on the Strengths of Epoxy Resin Mortar under Heat Exposure (열을 받은 에폭시 수지 모르터의 강도에 관한 연구)

  • 연규석;강신업
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.24 no.4
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    • pp.92-98
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    • 1982
  • The major objective of this study was to investigate the heat resistance of epoxy resin mortar. For this purpose, these tests of compressive and bending strength were accomp- olished with various heating temperature (40˚C, 60˚C, 80˚C, 100˚C, 120˚C), and with various mixing ratio (1: 2, 1: 4, 1: 6, 1: 8, 1:10, 1:12, 1:14). The exprimental resin was to be Epi-Bis type epoxy resin, which is widely used as construction materials. The results obtained are summarized as follows; 1. The variations of color tone started to begin at 60˚C, and it has come out very heavy at 120˚C. It was assumed that the decrement of weight resulted from carbonization were about 0.22% at 100˚C, and about 0.34% at 120˚C. 2. The compressive and bending strength were increased with temperature rise up to 80˚C, but these were made rapid decrease when the given temperature was over. And so, the mean decrement of compressive and bending strength at 120˚C reached up to 35.5% and 26.4%, respectively. 3. The regression equation between compressive and bending strength for epoxy resin mortar under heat exposure were obtained as follows; od=0. 371oc+39. 23 (r=0. 986) And the estimated value of bending strength was corresponded to about 37 percent in comparing with that of the compressive strength. 4. Consquently, the heat resistance temperature of epoxy resin mortar was to be around 80˚C, and it was generally very low values. But it was regarded that the epoxy resin mortar will not be difficult with materials of civil engineering works and agricultural structures.

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Synthesis of Gamma Aluina Powder for Catalytic Support from Kaolin (카올린으로부터 촉매담체용 감마알루미나 분말의 합성)

  • Kang, H.K.;Park, H.C.;Choi, I.S.;Lee, H.;Son, M.M.
    • Korean Journal of Materials Research
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    • v.6 no.9
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    • pp.943-949
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    • 1996
  • 카올린에서 추출된 황산알루미늄 용액으로부터 촉매담체용 r-AI2O3분말 합성에 대하여 연구하였다. 황산알루미늄 용액을 교반중의 에탄올(ethanol)에 적하하여 단일상(single phase)의 AI2(So4)3 18H2O석출물을 제조하고 이 석출물의 하소로부터 r-AI2O3분말을 합성하였다. 이 분말을 100$0^{\circ}C$에서 2시간 하소하였을 때 열적안정성을 보였으나, 120$0^{\circ}C$-2시간 하소에서 $\alpha$-AI2O3 로 전이하였다. r-AI2O3의 열적안정성에 미치는 BaO 첨가의 영향을 조사 연구하였다. 첨가량은 r-AI2O3에 대해서 1.0-6.0wt%로 하였다. BaO를 4.0wt%첨가한 시료는 AI2O3-BaO.6AI2O3(hexa-aluminate)혼합상생성으로 인하여 120$0^{\circ}C$에서 r-AI2O3의 전이를 방지하는데 효과적이었다. BaO를 4.0wt%첨가한 시료와 BaO를 첨가하지 않은 시료에 대하여 r-AI2O3$\longrightarrow$ $\alpha$-AI2O3전이에 따른 비표면적을 조사하여 보았다. 120$0^{\circ}C$-2시간에서 BaO 4.0wt% 첨가한 시료와 BaO를 첨가하지 않은 시료의 비표면적은 각각 95$m^2$/g과 50$m^2$/g을 유지하였다.

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Effects of steaming on saponin compositions and antiproliferative activity of Vietnamese ginseng

  • Le, Thi Hong Van;Lee, Seo Young;Lee, Gwang Jin;Nguyen, Ngoc Khoi;Park, Jeong Hill;Nguyen, Minh Duc
    • Journal of Ginseng Research
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    • v.39 no.3
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    • pp.274-278
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    • 2015
  • Background: Steaming of ginseng is known to change its chemical composition and biological activity. This study was carried out to investigate the effect of different steaming time-scales on chemical constituents and antiproliferative activity of Vietnamese ginseng (VG). Methods: VG was steamed at $105^{\circ}C$ for 2-20 h. Its saponin constituents and antiproliferative activity were studied. The similarity of chemical compositions between steamed samples at $105^{\circ}C$ and $120^{\circ}C$ were compared. Results: Most protopanaxadiol and protopanaxatriol ginsenosides lost the sugar moiety at the C-20 position with 10-14 h steaming at $105^{\circ}C$ and changed to their less polar analogues. However, ocotillol (OCT) ginsenosides were reasonably stable to steaming process. Antiproliferative activity against A549 lung cancer cells was increased on steaming and reached its plateau after 12 h steaming. Conclusion: Steaming VG at $105^{\circ}C$ showed a similar tendency of chemical degradation to the steaming VG at $120^{\circ}C$ except the slower rate of reaction. Its rate was about one-third of the steaming at $120^{\circ}C$.

Effects of Density, Temperature, Size, Grain Angle of Wood Materials on Nondestructive Moisture Meters

  • Pang, Sung-Jun;Jeong, Gi Young
    • Journal of the Korean Wood Science and Technology
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    • v.47 no.1
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    • pp.40-50
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    • 2019
  • The aim of this study was to investigate the effects of density, temperature, size, and grain direction on measurement of moisture contents (MC) of wood materials non-destructively. The MC of different sizes of solid wood, glulam, and CLT from larch (larix kaempferi, $560kg/m^3$) and pine (pinus koraiensis, $430kg/m^3$) were measured using the dielectric type and resistance type meters. The specimens were conditioned in the environmental chamber to be equilibrium moisture content (EMC) of 12 % and 19 %. When density setting in dielectric type meter was increased from $400kg/m^3$ to $600kg/m^3$, the MCs of specimen (S-L-100-E) were decreased from 13.4 % to 11.3 %. However, when wood group (WG) setting in resistance type meter was changed from WG1 to WG4, the measured MCs were increased from 9.2 % to 12.3 %. When temperature setting in resistance type meters was changed from 0 to $35^{\circ}C$, the MC was decreased from 17.0 % to 13.0 %. The MCs measured by dielectric type meter for larger specimens (S-L-100-E_11.3 %, G-L-240-E_11.7 % and C-L-120-E_12.8 %) were higher than those of small size specimens (S-L-30-E_8.7 %, G-L-150-E_10.3 %, and C-L-90-E_9.7 %). The MCs measured by resistance type meter for larger specimens (G-L-240-E_11.6 % and C-L-120-E_13.3 %) were also higher than those of small size specimens (G-L-150-E_10.4 %, and C-L-90-E_11.8 %). The resistance type meter was not affected by the grain direction but the dielectric type meter were affected by the grain direction. The MC measured by resistance type meter for G-L-120-E perpendicular to grain direction was 11.5 % and the measured MC parallel to grain direction was 11.3 %. The MC measured by dielectric type meter parallel to grain direction (12.1 %) was higher than that measured perpendicular to grain direction (10.7 %).

Mechanical Properties of $Al_2O_3-AlN$ Particulate Composite ($Al_2O_3-AlN$계 입자복합체의 기계적 성질)

  • 김영우;박홍채;오기동
    • Journal of the Korean Ceramic Society
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    • v.33 no.1
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    • pp.101-109
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    • 1996
  • The mechanical propertieso f sintered AlN with the addition of alumina were investigated The flexural strength of the AlN dispersed ALON specimens was higher than that of ALON and fracture toughness showed similar tendency. The high-temperature flexural strength of specimens which 50 and 64.3 mol% alumina was added to AlN was constant up to 100$0^{\circ}C$ with about 290 and 420 MPa respectively but abruptly decreased at 120$0^{\circ}C$ In the specimens which contained 5 and 30mol% alumina the flexural strength increased to about 14% at 100$0^{\circ}C$ and did not decrease at 120$0^{\circ}C$ compared to at room temperature.

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Denaturation of Heat Treated Lysozyme under High Pressure Conditions (고압조건에서 가열 처리된 Iysozyme의 변성)

  • Cho, Rae-Kwang;Hong, Jin-Hwan
    • Korean Journal of Food Science and Technology
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    • v.23 no.3
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    • pp.366-369
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    • 1991
  • In order to elucidate texturization mechanism of extrudated protein, egg white lysozyme was heated under high pressure conditions, and its solubility and changes of molecular weight were investigated. Under high pressure conditions of $100,\;300\;and\;600\;kg/cm^2$, solubility decreased gradually with increasing temperature in the samples heated at $70,\;120\;and\;150^{\circ}C$ and decreased notably with increasing pressure at $200^{\circ}C$. Polymerization was found in the samples heated at $150\;and\;200^{\circ}C$ while a band which located below monomer(low-molecular) could be recognized. Molecular weight of the low-molecular was estimated to be about $6,000{\sim}9,000$ and no smaller peptide was recognized. The polymerization may have occured by disulfide crosslinking in the samples heated at $120^{\circ}C$ but other crosslinking may have played a role in those at $150\;and\;200^{\circ}C$.

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Two-step Acid Hydrolysis Method for Producing Fermentable Sugar from Lignocellulosic Biomass (발효당 생산을 위한 목질계 바이오매스의 2단 산당화)

  • Park, Jang Han;Kim, Jun Seok
    • Korean Chemical Engineering Research
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    • v.54 no.1
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    • pp.1-5
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    • 2016
  • For obtain fermentable sugar, we conducted acid hydrolysis with lignocellulosic biomass without enzyme. The lignocellulosic biomass used pinus rigida and Palm residues (EFB; empty fruit bunches). In the acid hydrolysis, we consider the hydrolysis condition to reduce a denatured sugar. So this study was conducted 2-step acid hydrolysis. First-step hydrolysis used high concentration (72 wt%) sulfuric acid at $80^{\circ}C$. At the condition, we obtained 11.49 wt%, 32 wt% glucose conversion for pinus rigida and EFB. After the step, the liquor was dilute until 9~15 wt% acid concentration and conducted second hydrolysis at $50{\sim}120^{\circ}C$. In the second hydrolysis, we obtained maximum glucose conversion (pinus rigida 86.8 wt% (39 g/L) and EFB 95.3 wt% (32.4 g/L)) at 9 wt% acid concentration and $120^{\circ}C$ for 80 min. All samples through the process are analyzed on the basis of mass balance.

Performance Experiment of H-120 Class Fire Damper for Offshore (해양플랜트용 H-120 Class 파이어 댐퍼의 성능 실험)

  • Jang, Sung Cheol;Hur, Nam-Soo;Kim, In-Whan
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.13 no.2
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    • pp.131-136
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    • 2014
  • In this paper, a fire resistance test was carried out in accordance with the change of the insulation conditions on the exposed side and unexposed side of a coaming to obtain the optimal insulation conditions for class H-120 insulation in connection with specimen1 of the preceding paper for an evaluation of the fireproof performance of fire dampers according to hydrocarbon fire conditions. In the test results, specimen2(88 mm, $171^{\circ}C$) met the class H-120 insulation conditions, but specimen3(76mm, $181^{\circ}C$) exceeded the thermal insulation acceptance criteria at 110 minutes. Therefore, specimen2(88 mm) represents the optimal insulation conditions as a possible lightweight materialas compared to specimen1. From a comparison of the test results, we concluded that the temperature increase of the coaming insulation surface was influenced by conductive heat from the bulkhead and that the coaming surface was influenced by radiant heat from the blade and coaming.

Evaluation of Autochemical Analyzer Toshiba 120 FR (자동화학 분석기 Toshiba 120 FR의 평가)

  • Park, Jum Gi
    • Korean Journal of Clinical Laboratory Science
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    • v.36 no.2
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    • pp.98-109
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    • 2004
  • The lower limit of detection, precision, setting method of target value, reportable range determination, recovery, linearity, and comparison study with another equipment was evaluated for the Toshiba-120FR chemistry autoanalyzer which was newly introduced at the Daejeon Veteran Hospital in Dec. 2003. Nineteen kinds of test for AST, ALT, ALP, LDH, GGT, TP, ALB, GLU, T-cho, T-bil, TG, UA, CAL, IP, AMY, HDL-C, LDL-C, Cre and BUN were performed to evaluate the lower limit of detection, precision, setting method of target value, reportable range determination, recovery, linearity, and comparison study with other equipment according to the NCCLS guidelines(EP5-A, EP6-P, EP9-A). The Toshiba-120FR autochemical analyzer showed good precision for all tested items. The data concerning the lower limit of detection, precision(total CV 0.47%~3.65%), setting method of target value, reportable range determination, recovery(93%~111%), linearity($R^2=0.997{\sim}0.999$), and comparison study(r=0.977~0.999) with other equipment was acceptable for all tested items. The results of evaluation for the Toshiba-120FR autochemical analyzer showed that this equipment could be used as an alternative to other equipment.

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