• 한국약용작물학회지
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• 제6권1호
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• pp.33-37
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• 1998

마의 껍질을 제거하거나 상처가 생겼을 때 발생하는 갈변현상을 억제할 수 있는 방법을 개발코자 실험을 수행한 결과는 다음과 같다. 1. 마는 박피후 시간이 경과할수록 갈변지수가 높아지는 경향를 보여 박피 후 15시간에 갈변지수가 장마는 38까지 증가한 반면 단마는 13이 었으며 이로서 장마가 단마보다 갈변이 빠르게 진행됨을 알 수 있었다. 2. 장마의 경우 NaCl 2M 처리시 갈변억제율이 48시간에 48%로 가장 높았고 특히 $80^{\circ}C$ 온탕처리의 경우 24시간까지 높은 억제율을 보였으나 이후 급격히 감소하는 경향을 보였다. 3. NaCl 1M 처리시 단마의 갈변은 43% 정도 억제 되었으나 NaCl 0.5M과 $70^{\circ}C$ 온탕처리는 비슷한 억제현상을 보였다. 그러나 $60^{\circ}C$ 온탕처리는 무처리보다 더 높은 갈변지수를 나타내었다.

• Applied Biological Chemistry
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• 제36권4호
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• pp.249-254
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• 1993

물과 70% 에탄올을 용매로 하여 추출온도, 시간, 용매첨가량, 추출횟수 등의 추출조건이 계피추출액의 무기성분과 물리적 성질에 미치는 영향을 조사하였다. 무기성분은 추출온도가 증가할수록 용출량이 많았고 추출시간 8시간 이상에서는 큰 변화가 없었으나 용매 첨가량 60배(v/w) 추출구에서 무기성분 함량이 증가하였으며 특히 물추출액에서는 Cu, Zn, Fe, Na 함량이, 70% 에탄올 추출액에서는 Fe, Mn, K의 용출량이 증가하였다. 285nm에서의 흡광도는 $60{\sim}80^{\circ}C$ 이상 추출에서는 감소하였다. Hunter Color value는 추출조건에 따라 a값의 변화가 가장 컸고 L값은 탁도와 유사한 경향으로 변화하여 추출온도, 시간, 용매량이 증가할수록 낮아졌다. pH는 횟수별 추출을 제외하고는 처리구간에 큰 변화가 없었다.

• 한국염색가공학회지
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• 제6권2호
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• pp.30-39
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• 1994

To study the printing behaviors of Polyester and cotton(P/C) fabrics printed with disperse and reactive dyes, the effects of alkalis on the fixation of reactive dyes and the alkali-stability of disperse dyes in various methods of fixation were examined. The anthraquinone disperse dyes which have diamino derivatives as substituents without hydroxy group, such as C.I. Disperse Violet 1(D.V.1), C.I. Disperse Violet 28(D.V.28) and C.I.Disperse Blue 60(D.B.60) showed good results of fixation without regard to the concentration of NaHCO$_3$. In case of high temperature steaming(HTS) and unsaturated steaming(US)/HTS, D.V. 1 was alkali-stable and effective for P/C printing. A good result was obtained with D.V.1 and C.I.Reactive Orange 13(R.O.13) paste of 4% $K_{2}CO_{3}$. It was found that the unfixed D.V.28 bearing chloro group can hinder the fixation of monochlorotriaxinyl reactive dyes, and D.B.60 made little stain on 100% cotton. In thermosol(Tm), the dye uptake of D.V.1 was not decreased so much, but those of D.V.28 and D.B.60 were greatly decreased.

• 한국태양에너지학회 논문집
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• 제24권1호
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• pp.7-12
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• 2004

Mixtures type PCM, $H_2O$-NaOH that has relatively large capacity of the latent heat and long duration of phase change temperature was developed and experimentally analyzed for the low temperature storage of the food and medical products. The results could be summarized as follows; 1. Borax as nucleating agent and acrylic polymer as thickening agent were added to $H_2O$ to prevent the supercooling and phase separation. 2. Phase change (solid$\leftrightarrows$liquid) duration of $H_2O$ added with NaOH was prolonged longer 50% than that of pure $H_2O$. 3. Phase change temperature of the latent heat material, $H_2O$-NaOH was $1.5\sim2^{\circ}C$ the maximum latent Heat was 279 kJ/kg at the NaOH addition of 1.3 wt.%. 4. The specific heat of $H_2O$-NaOH at the solid and liquid state was increased in proportion to the wt.% of NaOH, when NaOH of $1.15\sim1.60$ wt.% was added to $H_2O$, the specific heat of the solid state was increased from 3.19 kJ/kg to 5.84 kJ/kg and that of liquid state from 7.8 kJ/kg to 10.28 kJ/kg. 5. When NaOH of $1.15\sim1.60$ wt.% was added to $H_2O$, the total heat storage capacity composed of sensible and latent heat was $313\sim331.3$ kJ/kg and the maximum heat storage capacity was occurred at NaOH addition of 1.30 wt. %.

• 멤브레인
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• 제28권5호
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• pp.351-360
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• 2018

본 연구에서는 NaY 제올라이트 분리막의 프로필렌/프로판 분리 메카니즘을 규명하고자 하였다. 투과온도 증가 시에 프로필렌과 프로판 투과도는 증가하다 최고점을 보이고 감소하였고 약 $50-60^{\circ}C$ 부근에서 최대 선택도를 보였다. 혼합가스 프로판 투과도는 단일가스 투과도 보다 작았고, 프로필렌/프로판 혼합가스 선택도는 단일가스 투과선택도보다 우수하였다. 시간에 따른 혼합가스 투과거동 실험에서, 투과시간이 증가함에 따라서 프로필렌 투과도는 증가하는 반면, 프로판의 투과도는 감소하였고 선택도는 증가하였다. 위의 모든 실험결과는 NaY 제올라이트 분리막을 통한 프로필렌/프로판 분리는 선택적으로 흡착된 프로필렌의 프로판 투과 억제에 의해 일어나며 프로필렌 투과는 표면확산에 의해 지배된다는 것을 나타낸다. 프로필렌/프로판(89 : 11) 혼합가스에 대하여 분리막은 $50^{\circ}C$, 4 bar에서 선택도 12, 프로필렌 투과도 497 GPU를 나타내었다. 따라서 본 연구에서 제조된 NaY 제올라이트 모세관 분리막은 가격이 저렴하고 우수한 분리성능을 보이기 때문에 프로필렌/프로판 분리를 위한 유망한 분리막 소재임을 확인할 수 있었다.

• 한국산림과학회지
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• 제89권5호
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• pp.691-696
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• 2000

이분지털곰팡이(Syzygites megalocarpus)는 송이, 껄껄이그물버섯, 노란분말그물버섯, 냄새무당버섯, 암회색광대버섯아재비에서 출현하고 있었다. 이분지털곰팡이는 Malt Extract Agar, Mueller Hinton Medium, Potato Dextrose Agar에서 잘 자랐으며, 생육 최적온도는 $23^{\circ}C$ 내외, 최적 pH는 6.0 이었다. PDA배지에서 이분지털곰팡이는 2일째에 NaCl이 포함되지 않은 대조구에 비하여 5% NaCl에서는 생장이 36.5% 억제되었고 8% 이상 NaCl에서는 생장이 거의 없었다. 그러나 5일째에는 10% NaCl에서도 1.1cm 생장을 하는 것으로 관찰되었다. 송이균은 NaCl의 농도가 증가할수록 생장이 감소되어 2.5%에는 거의 생장하지 않았다. 따라서 이분지털곰팡이는 고농도의 NaCl에서도 생육이 가능하므로 송이 버섯에서 발생한 이분지털곰팡이를 NaCl 처리로 방제하기는 어려울 것으로 판단되었다.

• 대한기계학회논문집A
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• 제25권6호
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• pp.965-971
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• 2001

To estimate the reliability of 12Cr alloy steel, the material of turbine blade in the steam power plant, Its corrosion susceptibility and fatigue characteristics in NaCl and Na$_2$SO$_4$solution with the difference of concentration and temperature was investigated. The polarization tests recommended in ASTM G5 standard for corrosion susceptibility in the various corrosive solutions was estimated. It showed that the higher temperature, the faster corrosion rates and corrosion rates were the fastest in 3.5 wt.% NaCl and 1M Na$_2$SO$_4$solution. From these results, the degradation conditions were determined in distilled water, 3.5 wt.% NaCl and 1M Na$_2$SO$_4$solution at room temperature, 60$\^{C}$ and 90$\^{C}$ during 3, 6 and 9 months. Its surface had a few pits for long duration. But, it was not susceptible in sulfide and chloride condition of several temperatures. If the degraded 12Cr alloy steel and non-degraded one were compared with fatigue characteristics, Any differences were not found regardless of temperature and degradation period.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.190.1-190.1
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• 2014

The interfacial electronic structure of a bilayer of chloroaluminum phthalocyanine (ClAlPc) and pentacene grown on indium tin oxide (ITO) has been studied using synchrotron radiation-excited photoelectron spectroscopy. The energy difference between the highest occupied molecular orbital (HOMO) level of the pentacene layer and the lowest unoccupied molecular orbital (LUMO) level of the ClAlPc layer (EDHOMO - EALUMO) was determined and compared with that of C60/pentacene bilayers. The EDHOMO - EALUMO of a heterojunction with ClAlPc was found to be 1.4 eV, while that with C60 was 1.0 eV. This difference is discussed in terms of the difference of the ionization energy of each acceptor materials. We also obtained the complete energy level diagrams of ClAlPc/pentacene/ITO and C60/pentacene/ITO, respectively.

• 대한기계학회논문집
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• 제6권4호
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• pp.377-383
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• 1982

Acoustic emission (AE) of a high strength steel (SCM-4) was measured under stress corrosion cracking(SCC) test at a constant displacement in 3.5% artificial NaCl solution of 18.deg.C, 45.deg.C and 60.deg.C, respectively. The results are as follows; During the SCC test, AE is detected and AE count rate is approximately proportional to the crack growth rate. Even though crack is not propagated macroscopically, AE is detected. The crack growth rate of SCC and the AE count rate are higher for the solution of higher temperature, 45.deg.C and 60.deg.C, than for the solution of lower temperature, 18.deg.C. In the early stage of SCC, AE total counts mostly depend on crack growth. In the later stage, however, AE mostly depends on the film fracture and the dissolution of anode.

• 산업기술연구
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• 제20권A호
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• pp.39-44
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• 2000

Highly viscous biopolymer from alkali-tolerant Bacillus sp. was purified and its solution properties were investigated. The intrinsic viscosities for crude biopolymer and biopolymers purified by dialysis or CPC(cetylpyridinium chloride) treatment were 58.24, 73.60 and 42.18 dL/g, respectively. The intrinsic viscosity of biopolymer showed the maximum value at the neutral pH but it was decreased remarkably at the alkaline or acidic pH. Biopolymer exhibited the property of polyelectrolyte, showing the sharp decrease of intrinsic viscosity by the addition of NaCl. Intrinsic viscosity of dilute solution at the low NaCl concentration was exponentially dependent on temperature and its temperature dependency was increased with NaCl concentrations. The chain stiffness, coil overlap parameter, and critical concentration were 0.09, 5.25 and 0.07g/dL, respectively. Temperature dependency on intrinsic viscosity of biopolymer solution was different each other at $45^{\circ}C$. Flow activation energies at temperatures above $45^{\circ}C$ were constant, while those at temperatures below $45^{\circ}C$ increased with increase of added NaCl concentration.