• 자원리싸이클링
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• 제16권5호
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• pp.46-50
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• 2007

[ $Eu^{2+},\;Nd^{3+}$ ]로 도핑된 $CaAl_2O_4$ 청색 형광체를 고상반응법으로 제조하였다. 1 mol% $Eu^{2+}$로 doping된 형광체에 다양한 조성의 $Nd^{3+}$를 co-doping함에 따라 고휘도, 장잔광 특성을 보였다. 제조한 형광체에 대하여 XRD, SEM, TEM, 빛발광 특성을 조사하였다. $CaAl_2O_4:Eu^{2+}:Nd^{3+}$의 넓은 밴드의 UV로 여기된 빛발광 특성이 $Eu^{2+}$의 $4f^65d^1$에서 $4f^7$ 상태로 천이에 의해 기인된 청색영역(${\lambda}_{max}=440\;nm$)에서 관찰되었다. $Nd^{3+}$로 co-doping한 형광체는 여기광을 차단하였을 때 장잔광 발광 특성을 나타내었다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.1093-1095
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• 2006

An orange-emitting phosphor for inorganic electroluminescent device has been studied. Cu and Cl were co-doped in Mn-doped ZnS for a high-performing phosphor. The effect of $Mn^{2+}-doping$ concentration as well as $Mg^{2+}-sensitizer$ addition on the luminescence characteristics has been investigated.

• 한국산업융합학회 논문집
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• 제5권3호
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• pp.277-282
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• 2002

THF/toluene용매내에서 pyridine이 포함된 porphyrin과 $Re(CO)_5Cl$의 반응에 의해 새로운 porphyrin square(1)을 합성하였다. 2-(Methylene 15-crown-5)-nicotinoyl chloride ester(2)는 $CH_2Cl_2$용매내애서 2-Hydroxymethyl-15-crown-5와 nicotinoyl chloride 로부터 합성하였다. 형광 실험에서 게스트(2)가 호스트 (1)에 더해짐으로써 luminescence 가 감소되는 것을 알았다. 호스트-게스트계에서 (2)의 농도가 감소함에 따라 결합상수 k는 $1.13{\times}10^7M^{-1}$이었다. 이 계에 $Na^+$ 농도를 증가시킴으로써 luminescence는 현저히 증가하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 제5회 영호남 학술대회 논문집
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• pp.133-136
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• 2003

New porphyrin square (1) was prepared by reaction of porphyrin containing pyridine and $Re(CO)_5Cl$ in THF/toluene solvent. 2-(Methylenel5-crown-5)-nicotinoly ester(2) was synthesized by reaction of 2-(Hydroxymethyl-15-crown-5 and nicotinoly chloride in $CH_2Cl_2$. In fluorescence quenching studies luminescence was quenched by addition of the guest(2) into host(l). In the host-guest system we could obtain binding constant (K=$1.13{\times}10^7M^{-1}$) at decreasing concentration of (2). But the luminescence was dramatically increased after $Na^+$ was added into the host-guest system.

• Preventive Nutrition and Food Science
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• 제10권2호
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• pp.145-150
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• 2005

This study was carried out to examine the properties of sample amount and storage conditions on the accumulated pulsed photostimulated luminescence (PPSL) signals of soybean paste powder. Difference amounts (0.1, 0.5 and 1 g) of soybean paste powder samples stored in normal room and darkroom conditions were measured. The PPSL signals of the soybean paste powders significantly increased with irradiation dose up to 10 kGy. The PPSL signals of irradiated soybean paste powder samples decreased with increasing storage periods. The decay rates were similar to regardless of storage conditions and sample amount. The PPSL signals of the irradiated soybean paste powder measured for 120 s were higher than those measured for 60 s. These results indicated that although the PPSL signal of all soybean paste powder samples decreased with increasing storage time, detection of irradiated samples was still possible after 12 months of storage regardless of sample amount and measurement times in both normal room and darkroom conditions.

• 반도체디스플레이기술학회지
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• 제6권4호
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• pp.29-32
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• 2007

Zinc gallate, $ZnGa_2O_4:Mn^{2+}$ co-doped with different concentrations of $Mg^{2+}$ (0.001- 0.5 mol%) was prepared by solid state synthesis method. These compositions were investigated for their photoluminescence and cathodoluminescence properties. The optimized composition $Zn_{0.990}Mg_{0.005}Ga_2O_4:Mn_{0.005}$ shows higher luminescence intensity compared to the parent phosphor. The intense green emission peak was found at 504 nm. The $Mg^{2+}$ doping does not affect much the decay time. It remains <10 ms for these compositions which make them potential candidate for application in TV screens.

• 방사선산업학회지
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• 제7권1호
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• pp.1-5
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• 2013

Photostimulated luminescence (PSL) and thermoluminescence (TL) analyses were applied to identify the cookie molds mixed with 2 mg of 10 kGy-irradiated minerals according to cookie processing methods and sonication time (0~60 min) for mineral separation. PSL analysis showed that photon counts of cookies, dried or baked, ranged intermediate levels between the lower and upper threshold (700~5,000 counts/60 s), thereby showing its unsuitablility for screening of irradiated cookie. The TL glow curve intensities, measured according to mineral separation time (5, 10, 20, 40 and 60 mins) from the cookies using a sonicator, were high enough to identify irradiation status and significantly increased with the time in dried cookies. Those of baked cookies, however, were relatively low and not linearly increased with the time, but still possible to identify them (p<0.05).

• 한국식품과학회지
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• 제42권2호
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• pp.136-141
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• 2010

최근 방사선 조사는 식품의 발아억제, 살충, 살균 및 숙도조절을 위한 화학약품 처리 등의 대체방안 뿐만 아니라 식품의 저장 및 가공기술로서 인정받고 있으며, 우리나라를 비롯한 약 40개국에서 상업적인 조사식품을 생산하고 있어 이에 대한 정확한 정보를 제공하기 위한 신뢰성 있는 검지기술이 요구되고 있다. 방사선 조사식품 검지법 대상 식품 중 건조향신료 19품목에 방사선 조사 최대 허용선량인 10 kGy까지 $^{60}Co$ 감마선을 단계별로 조사하고 이를 광자극발광법(Photostimulated Luminescence, PSL)을 이용하여 검지특성을 확인하였다. PSL 측정 결과, 건조향신료 19품목 중 14품목은 1 kGy 조사된 시료에서, 1 품목은 5 kGy에서 조사시료(positive)의 threshold value인 5000 이상의 photon count/60 sec로 측정되어 방사선 조사여부의 확인이 가능하였다. 하지만 후추류, 육두구, 계피의 경우는 특이적으로 PSL 측정에 낮은 감도를 보이거나 미네랄 함량이 낮아서 최대 허용선량인 10 kGy 조사시료에서조차 방사선 조사여부의 확인이 불가능하였으며, 이 품목의 경우 열발광분석법(Thermoluminescence, TL) 등을 이용한 방사선 조사여부의 판정이 필요하였다. 또한 식물의 잎을 이용하는 향신료는 비조사 시료와 1 kGy 및 10 kGy 조사시료를 혼합하였을 때, 1 kGy 선량으로 조사된 시료가 1% 혼합된 시료에서도 방사선 조사여부의 확인이 가능하였다.

• 한국식품과학회지
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• 제30권3호
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• pp.498-501
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• 1998

광자극발광기(PSL)를 식품의 방사선조사 여부 판별에 적용 가능한지를 검토하기 위하여, 고춧가루, 건조혼합향신료, 새우, 감자, 콩나물콩, 건조 무화과, 생밤, 건조오징어, 건조대구포 등을 $^{60}Co\;{\gamma}-$선을 사용하여 방사선을 조사하고 PSL photon counts를 측정하였다. 비조사 시료의 photon counts는 감자의 경우는 2,000 이하, 그 외의 시료의 경우는 모두 1,000 이하를 나타냈다. 조사 시료는 건조 무화과(0.5 kGy), 생밤(0.2 kGy), 건조오징어(0.5 kGy)를 제외하고는 1,000 이상을 나타냈으며, 조사량에 따라 photon counts가 대부분 증가하였다. 따라서 PSL은 식품을 방사선 조사했는지 여부를 일차 판별하는 데 사용할 수 있음이 확인되었다.

• Current Applied Physics
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• 제18권11호
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• pp.1403-1409
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• 2018

In the present study, the $SrMoO_4:Eu^{3+}$ phosphors has been synthesized through hydro-thermal co-precipitation method, and single factor and orthogonal experiment method was adopted to find optimal synthesis condition. It is interesting to note that hydro-thermal temperature is a prominent effect on the luminescent intensity of $SrMoO_4:Eu^{3+}$ red phosphor, followed by co-precipitation temperature, calcining time, and the doping amount of $Eu^{3+}$. The optimal synthesis conditions were obtained: hydro-thermal temperature is $145^{\circ}C$, co-precipitation temperature is $35^{\circ}C$, the calcining time is 2.5 h, and the doping amount of activator $Eu^{3+}$ is 25%. Subsequently, the crystalline particle size, phase composition and morphology of the synthesized phosphors were evaluated by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The results show that these phosphors possess a scheelite-type tetragonal structure, and the particle size is about $0.2{\mu}m$. Spectroscopic investigations of the synthesized phosphors are carried out with the help of photo-luminescence excitation and emission analysis. The studies reveal that $SrMoO_4:Eu^{3+}$ phosphor efficiently convert radiation of 394 nm-592 and 616 nm for red light, and the luminescence intensity of $SrMoO_4:Eu^{3+}$ phosphors is improved. $SrMoO_4:Eu^{3+}$ phosphors may be a potential application for enhancing the efficiency of white LEDs.