• Title/Summary/Keyword: ultrasonic process

검색결과 673건 처리시간 0.051초

물리·화학적 공정을 이용한 해수 동물성 플랑크톤 Aretemia sp.의 소독 (Inactivation of Seawater Zooplankton Aretemia sp. using Physical and Chemical Processes)

  • 정창;김동석;박영식
    • 한국환경과학회지
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    • 제24권9호
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    • pp.1181-1188
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    • 2015
  • In this study, we discussed about the application of the single physical and chemical treatment processes and the physical-chemical complex treatment processes on the inactivation of Artemia sp. in order to satisfy the USCG Phase II (United States Coast Guard). The results showed that initial disinfection rate of ultrasonic process in single batch process is higher than that of electrolysis. However, the inactivation rate showed slower than electrolysis. The inactivation rate of Artemia sp. on the single continuous treatment process ranked in the following order: homogenizer > electrolysis > ultrasonic process. Inactivation rate of Artemia sp. in continuous homogenizer-electrolysis complex process was reached at 100% immediately. A synergistic effect of ultrasonic-electrolytic complex process was found to be a small. The order of processes in a complex process did not affect the disinfection performance.

Ultrasonic Velocity and Absorption Measurements in Egg White

  • Kim, Jeong-Koo;Bae, Jong-Rim
    • The Journal of the Acoustical Society of Korea
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    • 제21권3E호
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    • pp.126-131
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    • 2002
  • Ultrasonic measurements are made in egg white to study the properties of the solution of the natural protein. The high-Q ultrasonic resonator method is used to get the ultrasonic absorption spectra over the range 0.2-10 ㎒ at 20℃. It is proportional to the 1.25th power of the frequency. The gelation process caused by heat is studied from the change in the velocity and the absorption. at 3 ㎒ using the pulse echo overlap technique over the range of 10-80℃. The absorption decreases with increasing temperature up to 60℃ where it turns up sharply and rapidly increases thereafter. The strong absorption in the gel region is described by the interaction between the solution and the network structure made of protein. Very slow variation in time elapse is observed after the temperature is quickly raised. It would be a real-time observation of the network building process and the characteristic time for the process is shown to be 400 min. A hysteresis phenomenon with respect to the temperature is observed. This phenomenon is associated with the memorizing effect of the network structure of protein of the gel.

초음파 성형시 진동전달 방향에 따른 미세패턴의 전사특성 고찰 (Replication Characteristics of Micro-Patterns according to the Vibration Transmission Direction in the Ultrasonic Imprinting Process)

  • 서영수;이기연;조영학;박근
    • 한국정밀공학회지
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    • 제29권11호
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    • pp.1256-1263
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    • 2012
  • The present study covers the ultrasonic patterning process to replicate micro-patterns on a polymer substrate. The ultrasonic patterning process uses ultrasonic waves to generate frictional heat between an ultrasonic horn and the polymer substrate, from which the surface region of the polymer substrate is softened sufficiently for the replication of micro-patterns. The ultrasonic patterning process can divided into two categories according to the direction of vibration transmission: direct patterning and indirect patterning. The direct patterning uses a patterned horn, and the ultrasonic vibration is transferred directly from the patterned horn to the substrate. On the contrary, the indirect patterning process uses a plain horn, and the micro-patterns are engraved on a mold that is located below the substrate. Thus, the micro-patterns are replicated as an indirect manner. In this study, these direct and indirect patterning processes are compared in terms of the replication characteristics. Additionally, the possibility of double-side patterning is also discussed in comparison with the conventional single-side patterning process.

2단계 침출 과정에서 발생되는 비산회로부터 초음파 활용하여 이트륨과 네오디뮴의 동시 추출 (Simultaneous Extraction of Yttrium and Neodymium from Fly Ash by Two-Step Leaching Process with Aid of Ultrasonic Wave)

  • Kim, Jae-Kwan;Park, Seok-Un
    • KEPCO Journal on Electric Power and Energy
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    • 제7권1호
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    • pp.153-159
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    • 2021
  • A two-step process for increasing the leaching efficiency of yttrium and neodymium from coal fly ash were investigated at solid loadings of 5.0 g ash ~1,000 g ash/l of 1.0 N~10.0 N H2SO4, temperature ranging from 30℃ to 90℃, ultrasonic leaching time of 1~10 hours, and ultrasonic power of 25~200 W. The yttrium and neodymium from coal fly ash were effectively leached into ion phases by step change of the first conventional dissolution at room temperature and then the second heating process with the aid of ultrasonic wave, and maximum leaching efficiency of yttrium and neodymium obtained were 66 % and 63 %, respectively. The activation energies for the leaching reaction of yttrium and neodymium at second heating process dependent on leaching time and temperature were derived to be 41.540 kJmol-1 and 507.92 kJmol-1, respectively. The optimum conditions for the maximum leaching of yttrium and neodymium were found to be the solid loading of 250 g ash/l of H2SO4, solvent concentration of 2.0 N H2SO4, and second step process of temperatures of 30℃ for 3 hours and then 90℃ for 4 hours with ultrasonic intensity of 100 W.

Study on the heat and mass transfer in ultrasonic assisting vacuum membrane distillation

  • Guo, Hao;Peng, Changsheng;Ma, Weifang;Yuan, Hetao;Yang, Ke
    • Membrane and Water Treatment
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    • 제8권3호
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    • pp.293-310
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    • 2017
  • An ultrasonic assisting vacuum membrane distillation (VMD) system was designed to promote the heat and mass transfer in membrane distillation (MD) process. Both the effects of operating conditions and ultrasonic parameters to permeation flux in this process were investigated; the heat and mass transfer mechanism was also being discussed in this paper. The results showed that the performance of VMD process was improved significantly by ultrasonic assisting. The permeation flux was boosted at a certain feed solution temperature, pressure at permeate side and feed solution velocity whether or not to PP and PTFE. The results also indicated that ultrasonic power and frequency also was the key factor affecting the mass and transfer efficiencies. The feed side transfer coefficient ($K_f$), corresponding to ultrasonic power ($K_f=4.406-0.026{\times}P+7.824{\times}10^{-5}{\times}P^2$) and ultrasonic frequency ($K_f=0.941+0.598{\times}f-0.012{\times}f^2+6.283{\times}10^{-5}f^3$), was obtained and employed in the modeling of ultrasonic assisting VMD process. The modeling results showed that the calculated value of $K_f$ aligned with experimental results well. Both variations of temperature polarization coefficient (TPC) and concentration polarization coefficient (CPC) were studied based on the obtained data. The results showed that both TPC and CPC were improved obviously by the ultrasonic parameters.

초음파 진동을 이용한 RFID 미세패턴 성형 (Fabrication of RFID Micro-pattern using Ultrasonic Vibration)

  • 오명석;이봉구;박명규
    • 한국생산제조학회지
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    • 제26권3호
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    • pp.344-349
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    • 2017
  • In this study, we developed a process technology to fabricate RFID tag antennas using a one-sheet inlay micro-pattern forming process by press-molding RFID tag antennas on insulation sheet layers, such as polymer films, using ultrasonic longitudinal vibration. In addition, a fine pattern applicable for RFID tag antennas was manufactured using a $25{\mu}m$ thick thin-plate square wire; this is in contrast to the method that uses a conventional round wire. The developed ultrasonic indentation process can be used to fabricate fine pattern of the RFID antenna using one piece of equipment. The simplified manufacturing process technology has a shorter manufacturing time and is more economical. The developed RFID tag antenna forming technique involves pressing the $25{\mu}m$ square wire directly on the thin sheet insulation sheet of maximum thickness $200{\mu}m$, using a 60 kHz ultrasonic tool horn.

수성 폴리머 도료를 이용한 초음파 스프레이 공정으로 형성된 폴리머 절연층 미세구조 특성 (Morphology Characteristics of Insulating Laser based on Aqueous Polymer Resin Fabricated by Ultrasonic Spray Coating Process)

  • 유정모;박채원;엄현진
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2016년도 추계학술대회 논문집
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    • pp.136-136
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    • 2016
  • Commonly used oil-based polymer resin has environmental and safety issues. Many researches for replacing the harmful solvent-borne resins to water-borne resins have been investigated to purify harmful environmental resources and follow the export and import of hazardous materials regulations. In this research, ultrasonic spray coatings of aqueous polymer resin were studied to fabricate thin insulating layer (${\sim}{\mu}m$) on the rectangular copper wire. It needs to have appropriate wettability between resin and substrate during the ultrasonic spray coating process to coat aqueous polymer uniformly. Furthermore, stabilities of coating solution and fabricating process are required to form thin insulating layer on the substrate. In here, physical characteristics such as viscosity of 6 types of commercial polymer dispersions and emersions were analyzed to confirm compatibility for ultrasonic spray coating process. These resins were dissolved in isopropyl alcohol, used for true solvent, and were diluted with ethanol, utilized for diluent. Also, solubilities, dispersion characteristics, and viscosities of these diluted polymer resin solutions were confirmed. Dispersion characteristic and viscosity of coating solution affects jetting of ultrasonic spray coating and these jetting characteristics influence morphologies of insulating layer. In conclusion, we have known that aqueous polymer solution should have outstanding dispersion characteristic and certain range of viscosity to fabricate thin polymer insulating layer uniformly with ultrasonic spray coating.

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Study on the Effects of Ultrasonic Wave for the Effective Hydrogen Generation by Electrical Discharge Plasma Process

  • Park Jae-Youn;Cong Nghi-Vu;Han Sang-Bo;Kim Jong-Seok;Park Sang-Hyun;Lee Hyun-Woo;Lee Su-Jung
    • 한국전기전자재료학회논문지
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    • 제19권6호
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    • pp.591-598
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    • 2006
  • The research was tried to investigate the hydrogen generation from water by the pulsed power plasma process. Hydrogen was generated by way of the electrical pulse power discharge process with the ultrasonic wave. The yield on the hydrogen generation was also studied with and without operating the ultrasonic generator, in which the applied high voltage was varied from 10 kV to 15 kV. Nitrogen and argon gases were used as working gases. As the results, the generation yield using the pure nitrogen gas is better than argon and mixed gases such as argon and nitrogen. Hydrogen concentration are significantly increased when the ultrasonic generator was operated with the electrical discharge simultaneously. It is increased with increasing the applied ultrasonic level as well.

초음파 테이블을 이용한 단결정 사파이어 웨이퍼의 ELID 연삭가공 특성 연구 (A Study on the ELID Grinding Properties of Single Crystal Sapphire Wafer using Ultrasonic Table)

  • 황진하;곽태수;이득우;정명원;이상민
    • 한국기계가공학회지
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    • 제12권4호
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    • pp.75-80
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    • 2013
  • Single crystal sapphire being used in high technology industry is a brittle material with a high hardness and excellent physical properties. ELID(Electrolytic In-Process Dressing) grinding technology was applied to material removal machining process of single crystal sapphire wafer. Ultrasonic vibration which added to material using ultrasonic table was adopted to efficient ELID grinding of sapphire materials. The evaluation of the ground surface of single crystal sapphire wafer was carried out by means of surface measuring by using AFM(Atomic Force Microscope), surface roughness tester and optical microscope device. As the results of experiment, it was shown that more efficient grinding was conducted when using ultrasonic table. In case of using #170 grinding wheel, surface roughness of ELID ground specimen in using ultrasonic table was superior to ELID ground specimen without ultrasonic table. However, In case of using #2000 grinding wheel, surface roughness of ELID ground specimen in using ultrasonic table was inferior to ELID ground specimen without ultrasonic table.

Development of a High Power Ultrasonic Transducer for Steel Pickling Process

  • Han, Chang-Soo;Kim, Jeong-Ha
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.65.3-65
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    • 2001
  • In order to apply for pickling line in cold rolling process, a high power magnetostrictive ultrasonic transducer was developed. The transducer is expected to overcome the shortcomings of conventional high power ultrasonic transducers. The transducer consists of Fe-Co-V alloy sheets for the magnetostrictive material, an ultrasonic horn made of Hastelloy to withstand acid solution, and electric driving circuit. In the development, the transducer was designed with the theoretical and numerical methods such as finite element method, and was characterized with experimental water tanks. The developed transducers turned out to be able to generate the sound pressure up to 20,000 Pa, and to be suitable for application ...

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