• 제목/요약/키워드: Science and Technology University

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A Senior High School Chemistry Laboratory Class Observed by University Students

  • Kamitani, Sachiyo;Arai, Yuka;Konishi, Yuki;Nakanishi, Shinsuke;Oshima, Takuya;Yamaguchi, Junko;Ishii, Arisa;Minagawa, Keiji;Yasuzawa, Mikito
    • 공학교육연구
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    • 제13권5호
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    • pp.15-19
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    • 2010
  • Upon request from the Tokushima Prefectural Senior High School of Science and Technology, two faculty staff members and eight students of The University of Tokushima visited the high school and set up a chemistry laboratory class for 59 students. Since the participating senior high school students were freshmen, four simple, safe and visual experiments were selected: 1) Water purification, 2) Surface modification, 3) Briggs-Rauscher reaction, and 4) Polymer synthesis and characterization. All experiments received a favorable reception as a follow-up questionnaire verified. Since the high school students enjoyed the experiments it is hoped that the results will strengthen the students' interest in chemistry. It was good opportunity for the observers; they recognized the difficulty of teaching students.

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High Repetition Wavelength-locked 878.6 nm LD Dual-end-pumped Nd:YVO4 1064 nm Laser

  • Li, Yue;Yu, Yong-Ji;Wang, Yu-Heng;Liu, Hang;Liu, He-Yan;Jin, Guang-Yong
    • Current Optics and Photonics
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    • 제2권6호
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    • pp.582-588
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    • 2018
  • A $Nd:YVO_4$ laser dual-end-pumped by a wavelength-locked 878.6 nm laser diode is presented. At the repetition rate of 500 KHz, the absorbed pump power of 58 W, an output power of 26.1 W at 1064 nm is obtained, corresponding to an optical-optical efficiency of 45%. The pulse width is 44.2 ns. Meanwhile, the effects of traditional 808 nm pumping and 878.6 nm dual-end-pumping on the output laser beam quality and pulse width are compared and analyzed in an experiment.

Wide-Tunable Mid Infrared Intra-cavity Optical Parametric Oscillator Based on Multi-period MgO:PPLN

  • Wang, Xiao-Chan;Wang, Yu-Heng;Zheng, Hao;Liu, Hong-Zhi;Yu, Yong-Ji;Wang, Zi-Jian
    • Current Optics and Photonics
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    • 제5권1호
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    • pp.59-65
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    • 2021
  • This paper reports a tunable diode-pumped folded intracavity Q-switched singly resonant optical parametric oscillator based on multi-period MgO:PPLN. A wide tuning mid-infrared parametric light from 2.78 ㎛ to 4.17 ㎛ was obtained in real time by changing the poled periods and temperatures. The maximum output power of 1.89 W at 3.2 ㎛, 1.53 W at 3.5 ㎛, 0.87 W at 3.8 ㎛ and 0.486 W at 4.1 ㎛ were achieved. The highest optical-optical conversion efficiency was 7.89%. During experiments, a range tunable output of 2.78-4.17 ㎛ in the mid-infrared range was achieved.

Thermal Spray of Nanostructured Materials

  • Hwang, S.Y.;Kim, J.H.;Kim, H.J.;Seong, B.G.;Jun, H.W.;Lee, H.W.;Seok, H.K.;Lee, C.;Yang, H.;Baik, K.H.
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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    • pp.55-55
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    • 2006
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