• 한국식품과학회지
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• 제27권1호
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• pp.30-35
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• 1995

전분 추출공정을 개선하기 위한 목적으로 감마선 조사기법을 이용하였다. 감마선 조사에 의해 옥수수 시료의 일반성분은 변화가 없었으며, 미생물 오염도는 크게 감소하여 메옥수수의 경우 1 kGy, 찰옥수수의 경우 5kGy의 조사로 모든 미생물을 완전히 사멸시킬 수 있었다. 수침 및 아황산 용액에서의 수분흡수 속도상수는 침지온도 및 감마선 조사선량과 비례하여 증가되었으며 실온에서 6개월간 저장후에도 감마선 조사효과가 뚜렷하였다. 또한 아황산 용액은 수침에 비해 옥수수의 수화에 매우 효과적이며, 감마선 조사의 병용으로 그 효과를 더욱 향상시킬 수 있었다. 아황산농도 0.2%, $50^{\circ}C$, 40시간의 침지조건에서의 전분추출에 있어서 메옥수수와 찰옥수수 모두 감마선 조사로 전분의 수율을 최고 38%와 22%씩 증가시킬 수 있었으며, 추축된 전분의 색도는 찰옥수수 10 kGy 전분만을 제외하고는 모두 시료간에 유의적인 차이가 나타나지 않았다.

• Macromolecular Research
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• 제11권5호
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• pp.352-356
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• 2003

The objectives of this study were to investigate the influence of gamma irradiation for sterilization on poly(D,L-lactide-co-glycolide) (PLGA) with different molecular weight and the effect of gamma irradiation on the release behavior of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU, carmustine) from PLGA wafer with various irradiation doses. The effect of gamma irradiation on PLGA was evaluated by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and electron paramagnetic resonance (EPR). The weight average molecular weight (M$_{w}$) and glass transition temperature (T$_{g}$) of PLGA decreased after gamma irradiation. The extent of M$_{w}$ reduction was dependent on irradiation dose and PLGA molecular weight. Using EPR spectroscopy, we successfully detected gamma irradiation induced free radicals in PLGA. The gamma irradiation increased the release rate of BCNU from PLGA wafer at applied irradiation doses except 2.5 Mrad of irradiation dose in this study.study.

• 한국안전학회지
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• 제13권4호
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• pp.172-179
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• 1998

The effects of $^{60}Co\;{\gamma}-Ray$ irradiation on TSC characteristics of TFE type polytetrafluoroethylene(PTFE) were investigated. The $\alpha$ peak on TSC curve of PTFE was decreased, while the $\beta$ peak was reversely increased by the increasing of $\gamma$-irradiation doses up to 80 krad(0.8 kGy). Moreover, $\alpha$ and $\beta$ peaks on TSC curve of the irradiated PTFE are changed with the increasing of the forming temperature and forming electric field. In annealing the irradiated PTFE specimens at room temperature in air, it was shown a continuous recovery of TSC characteristics with time, which is assumed the traped charge carriers are liberated from the shallow traps and undergoes a recombination process during room temperature decay.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1142-1143
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• 2008

As well known, the maximum power point tracking (MPPT) is an important role in photovoltaic (PV) power systems. MPPT finds and maintains the operation of PV at the maximum power point when the irradiation and cell-temperature change. In this paper, the studied system includes a PV array, a Buck-Boost DC/DC converter, a DC/AC inverter and it is connected to the three phase power system. The solar array operates as a non-linear voltage source. The P&O algorithm with power feed-back is used to control the operating point of PV array at the maximum power point. The effects of irradiation and cell-temperature on the dynamic responses are also considered.

• Current Research on Agriculture and Life Sciences
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• 제32권3호
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• pp.131-134
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• 2014

The thermal death kinetics of the Black timber bark beetle, Xylosandrus germanus, was investigated to develop a heat treatment for control of infested wood packing materials used to export goods. To determine the feasibility of microwave irradiation as an alternative control method, laboratory experiments irradiating wooden blocks of Douglas fir ($200{\times}200{\times}250mm$), which were artificially infested with adults, with 2.45 GHz of microwave energy. All (100%) Ambrosia beetle adults were killed by both hot water treatments and microwave irradiation at $52^{\circ}C$ and $58^{\circ}C$, respectively. Probit analyses estimated the internal wood temperature required to produce Probit (0.99) efficacy to be $64.7^{\circ}C$ (95% CI $62.4-69.9^{\circ}C$) at one minute after microwave treatment.

• 한국자원식물학회지
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• 제11권2호
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• pp.124-130
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• 1998

It failed occasionally to take a reasonable emergence rate since tobacco (Nicotiana tabacum L.) seeds were planted on late Jan. showing lowest temperature. This experiment was done to measure the effect of GA3 (concentration ; period) , light quality (red ; white ; dark) during or after its treatment, daily irradiation hours( 0 ; 8 ; 12 ;16) and germination termperature (20 or 10 $^{\circ}C$ ocnstant ; 20/1$0^{\circ}C$ alternating) on the germination rate. Red and white light given during grmination showed no differences between the other daily irradiation hours except that 8 hours red light delayed germination although their 12 hours irradiation had the gratest rate. The rate was increased with increased concentration to GA3 0.01 mM or increased imbibition period to 3 days although the rate of cv. NC 82 was less than that of cv. Burley 21 in the case of dark imbibition of GA3 but daily 12 hours irradiation during germination. Light quality forced during GA3 imbibition eliminated such effect of GA3 shown in the darkness so that only light quality pretreatment and termperature during germinition were affected on the rate. The germination rate of thecultivars was decreased in the order of red, white light, darkness meaning that it was highly influenced by the light quality during GA3 treatment. Regardless of GA3 or light quality treatment,on the other hand, the rate was greater in 20 $^{\circ}C$ constat than 1$0^{\circ}C$ constant and 20/1$0^{\circ}C$ alternating germination temperature having similar germinative patterns.

• Bulletin of the Korean Chemical Society
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• 제32권6호
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• pp.1957-1964
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• 2011

Various reaction conditions uding temperature, time and type and concentration of templates have been changed in order to facilely synthesize, especially with microwave (MW) heating, SAPO-34 molecular sieves. SAPO-34 molecular sieve can be synthesized rapidly with microwave irradiation from a gel containing tetraethylammonium hydroxide (TEAOH) as a template. However, other several templating molecules lead to SAPO-5 molecular sieve under microwave irradiation even though SAPO-34 is obtained by conventional electric synthesis from the same reactant gels. Moreover, SAPO-34 can be obtained more easily by increasing the TEAOH or silica concentration or by increasing the reaction temperature. SAPO-34 can be obtained within 5 min in a selected condition (high temperature of 210 $^{\circ}C$) with microwave heating, which may lead to a continuous production of the important material. SAPO-34 synthesized by microwave irradiation is homogeneous and small in size and shows acidity and a stable performance in the dehydration of methanol and 2-butanol to olefins, suggesting potential applications in acid catalysis.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2005년도 춘계학술발표대회 개요집
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• pp.106-108
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• 2005

The instrumented fuel irradiation test at a research reactor is needed to evaluate the performance of the developed nuclear fuel. The fuel elements can be designed to measure the center line temperature of fuel pellets during the irradiation test by using temperature sensor. The thermal sensor was composed of thermocouple and sensor sheath. Micro-laser welding technology was adopted to seal between seal tube and sensor sheath with thickness of 0.15 mm. The soundness of welding area has to be confirmed to prevent fission gas of the fuel from leaking out of the element during the fuel irradiation test. In this study, fundamental data for micro-laser welding technology was proposed to seal temperature sensor sheath of the instrumented fuel element. And, micro-laser welding for dissimilar metals between sensor sheath and seal tube was characterized by investigating welding conditions. Moreover, the micro-laser welding technology is closely related to advanced industry. It is expected that the laser material processing technology will be adopted to various a pplications in the industry.

• 조명전기설비학회논문지
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• 제26권11호
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• pp.30-39
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• 2012

The characteristics of I-V and P-V of solar cell nonlinearly changes according to irradiation, temperature and load. Therefore, to use efficiently PV system, operating point must be always operating at maximum power point. Also, PV system is semiconductor, so it generates loss by temperature. But because of conventional MPPT methods are not considering temperature, it has problem which decrease efficiency. This paper proposes temperature measurement based optimal voltage(TMOV) MPPT algorithm using temperature measurement based optimal voltage. It analyzes characteristics of solar cell according to irradiation and temperature and conventional MPPT methods. The TMOV control algorithm proposed in this paper is compared and analyzed conventional MPPT methods. The validity of this paper proves using this result.

• Nuclear Engineering and Technology
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• 제53권3호
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• pp.920-926
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• 2021

Capsules containing NaCl-MgCl₂ salt with 316L stainless steel or alloy N samples were irradiated in the Ohio State University Research Reactor for 21 nonconsecutive hours. A custom irradiation vessel was designed for this purpose, and details on its design and construction are given. Stainless steel samples that were irradiated during exposure had less corrosive attack than samples exposed to the same conditions without irradiation. Alloy N samples showed no significant effect of irradiation. This work shows a method for conducting in-reactor irradiation-corrosion experiments in static molten salts and presents preliminary data showing that neutron irradiation may decelerate corrosion of alloys in molten chloride salts.