• 한국패류학회지
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• 제24권3호
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• pp.243-251
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• 2008

진주의 감별기법상 UV-Vis의 흡수 스펙트럼 분석과 반사율 분석은 흑진주의 색깔이 자연 그대로인지 아니면 처리에 의한 결과인지를 구별하는데 중요한 요소가 된다. 또한 ED-XRF을 이용한 미량 원소 분석은 진주가 해수산인지 담수산인지 여부와 은염 또는 염색 처리 유무를 판단하는데 이용될 수 있다. 본 연구에서는 은염 또는 염색 처리되지 않은 여러 종류(담수양식진주, 아코야양식진주, 타히티흑양식진주)의 진주에 은염처리를 한 결과, 은 이온 고유의 스펙트럼이 진주 고유의 스펙트럼에 영향을 주어 UV-Vis흡수 스펙트럼이 변화되었다. 또한 반사율도 은염처리하기 전보다 낮아짐을 알 수 있었다. 특히 자연 색상의 타히티흑양식진주의 경우 400 nm, 500nm, 700 nm의 고유 흡수 스펙트럼을 갖고 있었으며, 자연색상의 담수흑양식진주의 경우 380-400 nm, 480-500 nm 두 개의 특징적인 흡수 스펙트럼으로 나타났다. 자연 색상의 담수흑진주에서는 자연 색상의 타히티흑진주와는 달리 700nm의 흡수 스펙트럼이 관찰되지 않았다. 직접 은염처리한 진주 9 개를 ED-XRF를 이용하여 분석한 결과, 처리시간이 증가함에 따라 진주 층에 침투된 은의 함량이 점차로 증가했음을 알 수 있었다. 또한 시중에서 구입한 흑진주 18 개를 분석한 결과, 은 이온의 상대 함유량이 약 0.1%를 경계로 은염 또는 염색 처리 여부를 판단하는 데 도움을 줄 수 있을 것으로 생각되었다.

• 전기학회논문지
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• 제57권9호
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• pp.1606-1611
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• 2008

Recently, The diagnosis techniques of electric facilities are developed on live line. This paper describes the discharge characteristics of polymer insulator(EPDM A type). Keeping the facilities in good working order, the goal of this paper will provide the information to enable user to easily judge conditions of facilities on the spot. The performance of polymer insulator is assessed from the KS C IEC 60270 and CEA LWIWG-01(96)(Tracking Wheel Test). As the results, UV generation patterns of polymer insulator grow like a jellyfish shape follow the ramping voltage. Discharging UVs are detected at about 31.25% of breakdown voltage. Just then, dimension of UV image is about $0.84cm^{2}$. The dimension of max. UV image is about $297.4cm^{2}$ at $160kV(V_{bd})$. The position of UV generation due to surface discharge of polymer insulator is the center of insulator in the early, then moved the ground side and the last, UV image moved through the junction part of source side. Surface of aged polymer insulator is cracked and faded due to arc. UV absorption spectrum of polymer insulator are appeared the C-H bond of scissoring vib. at $1014cm^{-1}$ and C=O bond of recombination structure. Also, recombined UV absorption peak such as C-H, N-H, and O-H is detected at the $3321cm^{-1}$. Through the paper, there are inspection data which are the relations between surface discharge of polymer insulator and UV detecting image.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 추계학술대회 논문집
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• pp.125-128
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• 1998

Electroluminescent(EL) devices based on organic thin films have attracted lots of interests in large-area light-emitting display. One of the problems of such device is a lifetime, where a degradation of the cell is possibly due to an organic layer's thickness, morphology and interface with electrode. In this study, light-emitting organic electroluminescent devices were fabricated using Alq$_3$(8-hydroxyquinolinate aluminum) and TPD(N,N'-diphenyl-N,N'-bis(3-methylphenyl)-[1-1'-biphenyl]-4,4'-diamine).Where Alq$_3$ is an electron-transport and emissive layer, TPD is a hole-transport layer. The cell structure is ITO/TPD/Alq$_3$/Al and the cell is fabricated by vacuum evaporation method. In a measurement of current-voltage characteristics, we obtained a turn-on voltage at about 9 V. And we used other buffer layer of PPy(Polypyrrole) with ITO/PPy/TPD/Alq$_3$/Al structure. We observed a surface morphology by AFM(Atomic Force Microscopy), UV/visible absorption spectrum, and PL(Photoluminescence) spectrum. We obtained the UV/visible absorption peak at 358nm in TPD and at 359nm in Alq$_3$, and at 225nm and the PL peaks at 410nm in TPD and at 510nm in Alq$_3$ and at 350nm. We also studied EL spectrum in the cell structure of ITO/TPD/Alq$_3$/Al and ITO/PPy/TPD/Alq$_3$/Al and we observed the EL spectrum peak at 510nm from our cell

• 한국식품과학회지
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• 제25권3호
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• pp.214-219
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• 1993

pH7.0으로 조절한 2M의 AsA 용액을 $85^{\circ}C$에서 25시간 갈변반응시켜서 생성된 물질 중 항산화효과를 지닌 물질을 분리하고 성질을 조사하였다. 투석내액 및 투석외액 갈변반응물질 모두 항산화성이 존재하였고 투석외액 갈변반응물질의 항산화효과가 더 크게 나타났다. 투석외액 갈변반응물질을 gel 여과하여 분리된 3가지 획분(A, B, C)중 갈변도가 가장 높고 환원력이 가장 낮은 획분(C)의 항산화효과가 가장 크게 나타났다. 항산화성이 중간정도인 획분(B)은 환원력의 세기와 갈변도가 세획분중 중간정도에 속하였고 환원력은 가장 높고 갈변도가 가장 낮은 획분(A)은 항산화효과가 가장 낮았다. UV-Visible spectrum에서 A획분과 B획분은 각각 266.1 및 257.4nm에서 최대흡광 peak를 나타냈으나 C획분은 274.8nm에서 약한 peak를 나타내었다. IR-spectrum 조사결과 A, B 및 C획분 모두 hydroxy 및 carboxylic group이 존재하였고 항산화성이 큰 B와 C분획은 carboxylic ester이었다.

• 한국식물병리학회지
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• 제13권1호
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• pp.63-68
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• 1997

In the screening of antiviral materials produced by actinomycetes, an isolate named B25 was fond to produce an antibiotic substance ASA, which showed a strong inhibitory activity against tobacco mosaic virus (TMV) infection. ASA was purified from culture broth of B25 by silica gel column chromatography, preparative TLC, and reversed phase HPLC. Also MS, IR, UV spectrum, and melting point of ASA were determined and analysed. ASA was white powder soluble in dimethyl sulfoxide, chloroform, and ethyl acetate, having absorption peaks at 223 and 328 nm in UV-VIS spectrum, and had a molecular weight of 548. ASA showed strong inhibitory effect on TMV infection when it was applied as a mixture of TMV to the upper surface of leaves of a local lesion host (Nicotiana tabacum c. Xanthi-nc). It also showed antimicrobial effect against yeast and some phytopathogenic fungi.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.316-316
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• 2010

Six metal-free organic dyes having thiophene (1), benzene-thiophene (2), thiophene-benzene (3), thiophene-pyridine(4), thiophene-thiophene (5), and pyridine (6) linkers between 9,9-dimethylfluorenyl terminal group and $\alpha$-cyanoacrylic acid anchor were synthesized. Among them, organic dye 5 showed the longest ${\lambda}}max$ value (424 nm) in UV-Vis absorption spectrum, better incident monochromatic photon-to-current conversion efficiency (IPCE), highest short circuit photocurrent density (JSC, 9.33 mA2/cm2), and highest overall conversion efficiency ($\eta$, 3.91%).

• 미생물학회지
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• 제10권3호
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• pp.109-116
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• 1972

Three strains among 120 adenineless mutants of Brevibacterium ammoniagenes described in the previous paper were screened out to accumulate UV absorbing substances in the culture broth. It was analyzed to be 5'-inosinic acid and hypoxanthine by means of two dimensional paper chromatography, UV absorption spectra and periodate oxidation. 5'-IMP was isolated from the culture broth of the mutant No. 203 with anion-exchange resin amberite IRA-400 and recrystallized from ethanol. It was proved identical to authentic sample by Infra-red absorption spectrum. The growth responses of the mutant No. 2013 were demonstrated to require adenine, but not with adenosine and 5'-AMP.

• 한국의류산업학회지
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• 제14권3호
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• pp.478-485
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• 2012

The dying properties of fabrics with Chaenomelis Fructus extract were studied through an investigation of the characteristic of Chaenomelis Fructus colorants, the effect of dyeing conditions (dye temperature, dyeing concentration, and times on dye uptakes), effect of mordant, effect of UV irradiation, and color change in addition, antimicrobial ability and deodorant ability were estimated. In the UV-Visible spectrum, the wavelength of maximum absorption of Chaenomelis Fructus extract was 280 nm and showed that tannin is the major pigment component. From the increase of absorbance by UV irradiation, it was assumed that catechol tannin color was developed through UV irradiation. An increased dyeing concentration resulted in a larger dye uptake. Dye uptake increased as the dyeing time and temperature increased. Chaenomelis Fructus extract showed relatively good affinity to silk than cotton. Mordant, Fe and Cu were effective to increase the dye uptake of cotton fabric in addition, the dye uptake of silk fabric mordanted with Fe and K improved. UV irradiation let the color of dyed fabrics develop regardless of the UV irradiation stage however, UV irradiation on the dyed fabric was more effective than on the extract for the color development. Dyed silk fabric showed very good antimicrobial abilities of 99.9% in addition, deodorant ability improved in the fabric dyed with Chaenomelis Fructus extract.

• Bulletin of the Korean Chemical Society
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• 제31권8호
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• pp.2175-2179
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• 2010

Quantum mechanical properties of unsymmetrical and unfunctionalized trans-stilbene derivatives 1-3, which had been prepared by solid-phase parallel syntheses, were characterized using mPW1PW91/6-311G(d,p) (hybrid HF-DF) calculations. The total electronic energies, normal vibrational modes, Gibbs free energies, and HOMOs and LUMOs of sixteen different structures from three different groups were analyzed. The energy differences between the HOMOs and LUMOs of the various unsymmetrical trans-stilbenes are in accord with the maximum absorption peaks of the experimental UV spectra of 1-3. The calculated normal vibrational modes of 21 were comparable with its experimental IR spectrum. The $\pi$-conjugation in the para-connected biphenyl group of 2 is better than the one in the metaconnected biphenyl group on the shorter side of 3.

• 한국전기전자재료학회논문지
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• 제15권7호
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• pp.627-633
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• 2002

Many isolated featureless domains were explicitly observed even at the air-water interface. We measured the surface pressure shift originating from the photo-isomerization of azobenzene units on the periphery of dendrimers. The maximum surface pressure was gradual1y increased and saturated by cyclic compression and decompression. By irradiation of 365 [nm] light, the surface pressure was increased, which was originated by the photo-isomerization process of the azobenzene group on the periphery from trans to cia form. The increase of the dipole moment ($\mu$), which may increase the interaction among Azo dendrimer molecules, made an important role on surface pressure shift. From the absorbance spectrum by UV irradiation and heat treatment, we can see that the absorbance in the UV region decreases with the increase of the UV irradiation time, but the peak at 350 m, characteristic of dendrimers in the LB monolayers, was not shifted until four irradiation cycles. This suggests that optical behavior and morphological change are affected by the functional group and the symmetric chain.