• Title/Summary/Keyword: electro-generation

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Second Order Nonlinear Optical Polyimides Containing Organic Chromophores with an Oxadiazole Segment (옥사디아졸 결합의 유기 발색단이 도입된 이차비선형 광학 이미드 고분자)

  • Do, Jung Yun;Kim, Bong Gun;Kwon, Ji-Yun
    • Applied Chemistry for Engineering
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    • v.18 no.1
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    • pp.77-83
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    • 2007
  • It is essential that second order nonlinear optical materials have low optical propagation losses in the wavelengths of second harmonic generation for practical applications in waveguides. Three dipolar chromophores substituted with nitro, cyano, and alkyl sulfone as an electron withdrawing group were prepared. The UV-Vis absorption spectra of the cyano and alkylsulfone chromophores showed a blue-shift compared to the nitro chromophore. The introduction of oxadiazole segment in the chromophore structure led to similar spectral shift. The blue-shift can produce low optical loses at second harmonics. The chromophores were successfully attached to a polyimide, yielding side chain polymers. The nonlinear optical property of the prepared optical polymers was determined by measuring electro-optic coefficient at 1.55 mm. The polymers exhibited high glass transition temperature of over $185^{\circ}C$ and thermal stability to $300^{\circ}C$ through differential scanning calorimeter analysis and thermal gravimetric analysis.

Evaluation of Muscle Fatigue Recovery Effect and Meridian Potential Change using Magnetic Acupuncture System (자화침 시스템을 이용한 경락전위 유발효과 및 근피로 회복 평가)

  • Kim, Soo-Byeong;Park, Sun-Woo;Ahn, Soon-Jae;Lee, Na-Ra;Lee, Seung-Wook;Min, Se-Eun;Kim, Young-Ho;Lee, Yong-Heum
    • Korean Journal of Acupuncture
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    • v.29 no.1
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    • pp.83-92
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    • 2012
  • Objectives : The purpose of this research was to develop the magnetic acupuncture system which used solenoid coil for magnetizing acupuncture needle. The system could generate the meridian electric potential (MEP) similar to the potential by manual acupuncture. Thus, we tried to confirm the therapeutic effect that is caused by the MEP generation. Methods : To confirm the MEP, we stimulated the magnetic acupuncture with at 2Hz, $92.7{\pm}2mT$, PEMFs (Pulsed Electro-Magnetic Fields) at ST37 and measured the evoked potential between ST36 and ST41. Also, we conducted a fatigue recovery test using isokinetic exercise in order to identify the therapeutic effect on musculoskeletal disorders. We chose LR9 as a stimulation point. To observe the state of fatigue, we measured the EMG and analyzed median frequency and peak torque for 20minutes. Results : We observed that MEP which incurred from magnetic acupuncture was higher than he reported MEP induced by manual acupuncture. Moreover, its modes were divided into two types by the direction of magnetic flux. When generating magnetic flux in the direction of acupoint, the positive peak voltage of the MEP was generated. In contrast, negative peak voltage of the MEP was generated whenever meganetic flux generated in the outward direction. As a result of fatigue recovery, the median frequency (MF) of the magnetic acupuncture group were recovered faster than that of the non-stimulation group. However, the peak torques of both groups were not restored until after 20 minutes. Conclusions : We confirmed that the magnetic acupuncture system can lead to the MEP similar to manual acupuncture. Moreover, the MEP had a therapeutic effect on the musculoskeletal disorders.

A Study on Cabbage Salting Brine Reuse Technology Combining an Electrochemical Method and Activated Carbon Adsorption (전기화학적 방법과 활성탄 흡착 연계 공정을 이용한 절임염수 재이용 기술 연구)

  • Lee, Eun-Sil;Kim, Daegi
    • Journal of the Korean Society for Environmental Technology
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    • v.19 no.6
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    • pp.536-542
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    • 2018
  • A system combining an electrochemical method and an adsorption system using activated carbon was assessed to facilitate the reuse of cabbage-salting brine. IrOx/Ti insoluble catalyst electrodes were used in the experiment. The results were analyzed to identify any changes in the residual chlorine concentration according to variations in the current density at a salinity of 10 %, as well as the capacity of the activated carbon to adsorb the residual chlorine and organic matter. For current densities of $500A/m^2$ and $1,000A/m^2$, the residual chlorine concentration did not increase, instead stabilizing once the current reached 0.33 Ah/L. To assess the adsorption efficiency according to the residual chlorine concentration, the unit amount of the adsorption can be estimated from $Y=0.0066+2.087{\times}10^{-4}b$. For both residual chlorine generation using an electrochemical method and chlorine removal through activated-carbon adsorption, the unit amount of adsorption was 0.33 g/g. The maximum amount of $COD_{Cr}$ organic matter adsorbed by the activated carbon was 0.021 g/g, while for $COD_{Mn}$, the value was 0.004 g/g.

Applying Rosen-type PZT plasma generation device for medical applications (로젠형 압전변압기를 적용한 의료융합 플라즈마기기)

  • Lee, Kang-yeon;Jung, Byung-Geun;Park, Jeong-sook;Park, Ju-Hoon;Jeong, Byeong-Ho
    • Journal of the Korea Convergence Society
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    • v.12 no.1
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    • pp.243-250
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    • 2021
  • In the medical field, applications of plasma are applied sterilize instruments mainly but with the advent of bio-plasma technology, the scope of application is expanding. Recently, In addition, high-density miniaturization with handheld is required for sophisticated procedures when irradiated directly or treated with non-standard conditions. Rosen-type PZT is a device with a structure that generates high voltage plasma by achieving voltage transformation through electro-mechanical coupling using piezoelectric effect.and is used in portable plasma generating devices as an advantage to increase energy density relatively. In this paper, Rosen-type PZT was modeled using equivalent circuits and was carried out and a plasma generating device for medical application was designed and prototype tested. Prototype plasma generating device generates an output voltage of 5.8 kV with 12V input power and is designed to operate at high voltage by applying the half-bridge topology power converter. The results of the study confirmed the availability of various medical devices, such as plasma jets or direct exposure equipment.

A Style Study on the Iranian Vampire Film (이란-뱀파이어 영화 <밤을 걷는 뱀파이어 소녀> 스타일 연구)