• Food Science and Industry
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• v.43 no.1
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• pp.53-63
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• 2010

• Bulletin of the Korean Chemical Society
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• v.18 no.9
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• pp.1014-1017
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• 1997

1,3-Dipropyloxycalix[4]arene dibenzocrown ethers were synthesized in the fixed 1,3-alternate conformation by the reaction of 1,3-dipropyloxycalix[4]arenes with a dibenzo dimesylates. Complexation toward alkali metal ions using ISEs showed a high cesium selectivity. Conformational flexibility of the corresponding 1,3-alternate calixcrown ether (4) with respect to the NMR time scale is found to depend on the temperature and polarity of the NMR solvent.

• Bulletin of the Korean Chemical Society
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• v.16 no.7
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• pp.578-582
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• 1995

The resonance ionization mass spectrometry (RIMS) system with angular reflectron type time-of-flight mass spectrometer (AREF-TOFMS) has been developed and characterized. The system is applied for the ultratrace determination of Pb element. The 2-color 3-photon laser ionization scheme is adopted for the study and the mass resolution of the system is determined as T/ΔT=1680. The calibration curve for Pb is obtained in the range of 100 ppb to 0.01 ppb by using standard solutions. The minimal amount of detection for the present RIMS system is determined as less than 100 femtograms (10-13 gram).

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.5 no.4
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• pp.281-287
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• 1976

Solar Radiation is effected by the astronomical condition, the collector inclination, the air and the climate conditions before it reaches an earth surface. Based on the data which have been collected and recorded by the Central Meteorological Office and other resources, the effects of those conditions in Korea are analysed and appraised in this report.

• Nuclear industry
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• v.17 no.2 s.168
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• pp.40-43
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• 1997

제245차 원자력위원회 의결에 따라 추진된 원자력 사업 추진 체제 조정 작업이 96년 말로 완료됨에 따라, 그 동안 한국원자력연구소가 수행하던 원자력 사업이 모두 산업체로 이관되었다. 이에 따라 1월 3일에는 한국전력기술(주)의 $\ulcorner$원자로설계개발단$\lrcorner$이, 1월 9일에는 한국전력공사의 $\ulcorner$원자력환경기술원발단$\lrcorner$이 대전 대덕연구 단지에서 각각 개소식 및 개원식을 갖고 업무를 개시하였다. 이번 사업 추진 체제 조정으로 지난 10여년간 논란이 되어 온 우리 나라 원자력 산업계의 구조적인 문제점이 해소되어, 세계무역기구(WTO 출범 등 급변하는 무한경쟁 시대의 세계 무역 환경에 적절히 대응할수 있는 체제로의 전환이 이루어짐으로써, 국내 원자력산업은 국제 경쟁력을 확보할 수 있는 기반을 구축하게 되었다. 원자력 사업 추진 체제 조정 작업의 추진 배경, 추진 경위, 조정 결과 등을 요약$\cdot$정리해 본다.

• Journal of Sensor Science and Technology
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• v.33 no.1
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• pp.34-39
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• 2024

Energy harvesting technology that converts the wasted energy resources into electrical energy is emerging as a semipermanent power source for self-powered electronics and wireless low-power sensor systems. Among the various energy conversion techniques, flexible piezoelectric energy harvesters (f-PEHs), using materials with piezoelectric effects, have attracted significant interest because they can harvest a small mechanical energy into electrical signals without constraints of time and space in various environments. In this study, we used a flexible piezoelectric composite film fabricated by dispersing BaHf_xTi_(1-x)O₃ (x = 0, 0.01, 0.05, 0.1) piezoelectric powders inside a polymeric matrix to facilitate f-PEHs. The fabricated f-PEH with optimal Hf contents (x = 0.05) generated a maximum output voltage of 0.95 V and current signal of 130 nA with stable electrical/mechanical disabilities under periodically bending deformations. In addition, we demonstrated a cantilever-type f-PEH and investigated its potential as a sensor by characterizing the output performance under mechanical vibrations at various frequencies. This study provides the breakthrough for realizing self-powered energy harvesting and sensing systems by adopting the lead-free piezoelectric composites under vibrational environments.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2011.05a
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• pp.391-392
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• 2011

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2011.10a
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• pp.473-474
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• 2011

• 기계와재료
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• v.9 no.4 s.34
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• pp.6-14
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• 1997

• 기계와재료
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• v.19 no.1 s.71
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• pp.20-29
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• 2007