• Title/Summary/Keyword: dipping time

Search Result 196, Processing Time 0.024 seconds

Fabrication of Ozone Bubble Cleaning System and its Application to Clean Silicon Wafers of a Solar Cell

  • Yoon, J.K.;Lee, Sang Heon
    • Journal of Electrical Engineering and Technology
    • /
    • v.10 no.1
    • /
    • pp.295-298
    • /
    • 2015
  • Ozone micro-bubble cleaning system was designed, and made to develop a unique technique to clean wafers by using ozone micro-bubbles. The ozone micro-bubble cleaning system consisted of loading, cleaning, rinsing, drying and un-loading zones, respectively. In case of the cleaning the silicon wafers of a solar cell, more than 99 % of cleaning efficiency was obtained by dipping the wafers at 10 ppm of ozone for 10 minutes. Both of long cleaning time and high ozone concentration in the wet-solution with ozone micro-bubbles reduced cleaning efficiency because of the re-sorption of debris. The cleaning technique by ozone micro-bubbles can be also applied to various wafers for an ingot and LED as an eco-friendly method.

A Study on the Preparation of Poly(vinyl alcohol) Polarizing Film (폴리비닐알코올 편광필름 제조에 관한 연구)

  • 김삼수;우화령;류원석
    • Textile Coloration and Finishing
    • /
    • v.16 no.4
    • /
    • pp.19-25
    • /
    • 2004
  • Both poly(vinyl alcohol)$(PVA)-I_2$ and PVA-dye polarizing film were prepared using PVA with number-average degree of polymerization of 1,700, 2,300, 2,600. The optical property of used dye in this study closed to the that of iodine. The PVA-dye polarizing film was prepared through the dyeing process. In comparison of the result of the measurement of the heat and humidity resistance of two types polarizing films, it of PVA-dye polarizing film was higher than that of a conventional $PVA-I_2$polarizing film. The transmittance and the polarization efficiency of PVA-dye polarizing film was significantly influenced by dye concentration, dipping time, salt concentration, and temperature of dye bath. The PVA-dye polarizing film exhibited a high polarization efficiency of 99.3% and a good transmittance of 42.4%.

High-resolution Seismic Study Using Weigh-drop at the Boundary of Pungam Basin (중력추를 이용한 풍암분지 경계 부근에서의 고해상도 반사파 탐사)

  • Kim, Hyoun Gyu;Kim, Ki Young
    • Economic and Environmental Geology
    • /
    • v.31 no.6
    • /
    • pp.519-526
    • /
    • 1998
  • A high-resolution seismic survey was conducted at the northeastern boundary of Pungam basin, one of the Cretaceous sedimentary basins in Korea. A 100 kg weight was used as an energy source and was found to be better than a sledge hammer in mapping deeper geologic structures. Several processing techniques such as f-k filtering, predictive deconvolution, and time-variant filtering are useful to enhance the signal-to-noise ratio by suppressing unwanted seismic energy. Four seismic units are recognized where many vertical faults are developed. The boundary fault between sedimentary rocks and Precambrian gneiss is identified along with a fracture zone of approximately 30 m wide. Bedding planes of the sedimentary rocks dipping westward are interpreted to be limbs of a syncline or volcanic flow. There faults and tilted bedding planes indicate that the basin had undergone significant tectonic deformation.

  • PDF

Natural Dyeing Using Sasa quelpaertensis Nakai (제주조릿대를 이용한 천연염색)

  • Lee, Hye-Sun;Park, Ji-Hye
    • Textile Coloration and Finishing
    • /
    • v.19 no.1 s.92
    • /
    • pp.17-23
    • /
    • 2007
  • Dyeing properties using natural material named Sasa quelpaertensis Nakai were investigated under various conditions such as fabric type, pH, concentration, temperature, dyeing time and dipping count. Sasa quelpaertensis Nakai is a unique material in that it is raised only at Halla mountain in Jeju island and is known to have healing effect. Overall, wool fabrics were better than cotton fabrics in all aspects of the dyeing properties showing reddish yellow. For the fastness properties, robbins washing and perspiration fastness were excellent but lightfastness was poor as expected.

Analysis of the Sol-Gel Coating Process for the Preparation of Supported TiO2 Composite Membranes ($TiO_2$ 복합 분리막의 제조를 위한 졸-겔 코팅공정 분석)

  • 현상훈;최영민
    • Journal of the Korean Ceramic Society
    • /
    • v.29 no.5
    • /
    • pp.403-409
    • /
    • 1992
  • The titania membrane thickness coated on the porous alumina support by the sol-gel method was analyzed using the slipcasting model. The thickness of calcined membrane layers increased linearly from 1.3 to 3.8 ${\mu}{\textrm}{m}$ with the square root of the dipping time (4~40 min). Growth rates of the thickness of wet gels and calcined layers were well described quantitatively by the slipcasting model. Through the regression of experimental data using model equations, the permeability and the pressure drop across wet gels, and the thickness and their growth rate constants of wet gels and calcined layers could be determined. It was also known that the gellation concentration of the TiO2 sol used in this work and the porosity of wet gel layes were 25 mol/ι and 0.53, respectively.

  • PDF

Central nervous system depressant effect of hot water extract of Ocimum sanctum Linn. (Labiateae)

  • Alamgir, Mahiuddin;Choudhuri, Shahabuddin Kabir;Jabbar, Shaila;Rajia, Sultana;Khan, Mahmud Tareq Hassan
    • Advances in Traditional Medicine
    • /
    • v.2 no.2
    • /
    • pp.101-105
    • /
    • 2002
  • A battery of neuropharmacological experiments showed the hot water extract of Ocimum sanctum Linn. (Labiateae) had a depressant effect on the central nervous system (CNS), but the aqueous extract showed no effect on it. The hot water extract reduced the spontaneous locomotor activity, exploratory head dipping, propulsive locomotion and exploratory ambulation as well as prolonged the pentobarbital induced sleeping time. The depressant effect starts from 60 minutes after the drug administration and continued to 180 minutes. The drug may exert central depressant effect by interfering with the function of the cortex.

Characteristics of $RuO_2$/n-GaN Schottky Diode ($RuO_2$/n-GaN 구조의 Schottky Diode 특성)

  • Kim, Dong-Sik
    • 전자공학회논문지 IE
    • /
    • v.46 no.3
    • /
    • pp.1-5
    • /
    • 2009
  • In this paper, we study the electrical characteristics of $RuO_2$/n-GaN Schottky diodes fabricated by using electrochemical metallization. The solution for GaN Schottky electrodes of $RuO_2$ is perchloric acid($HClO_4$). Thickness of $RuO_2$ layer depend on supplied voltage and dipping time. We verified the possibility of the rectifying and non-rectifying devices' electrode which was depend on the thickness of $RuO_2$ layer.

The Analysis of Performance for OFDM over Mutipath Delay Spread Channel (다중경로 지연확산 채널상에서 OFDM에 대한 성능분석)

  • Won, Young-Jin
    • 전자공학회논문지 IE
    • /
    • v.46 no.4
    • /
    • pp.78-82
    • /
    • 2009
  • We analyze an analysis of the performance of OFDM(Orthogonal Frequency Division Multiplexing) under multipath channel conditions, and to allow for different OFDM configurations. In this paper, the effects on multipath delay spread, peak power dipping, channel noise and time synchronization errors for the OFDM Signals are analyzed.

Antimicrobial Properties of Paper Treated with Acidic Liquid from Carbonized Rice Hull (왕겨초액 처리지의 항균 특성)

  • Min, Choon-Ki;Jo, Joong-Yeon;Shin, Jun-Sub;Lee, Se-Eun
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.43 no.2
    • /
    • pp.72-76
    • /
    • 2011
  • Antimicrobial activities of the Acidic Liquid originated from Carbonized Rice Hull(ALCRH) and the paper treated with ALCRH were investigated to apply ALCRH to functional paper products as a natural antimicrobial agent. ALCRH showed antimicrobial activity for bacteria and yeast, with higher performance for bacteria than for yeast. Antimicrobial activity was not developed on paper coated with ALCRH by bar coater probably due to the evaporation of antimicrobial compounds of ALCRH from the paper surface with time. Saturation of paper with ALCRH was essential to develop antimicrobial activity on the paper. Dipping paper in ALCRH solution was recommended as one of the effective ways to make antimicrobial paper.

High Purity Extraction and Simultaneous High-performance Liquid Chromatography Analysis of Curcuminoids in Turmeric (강황에서 curcuminoids의 고순도 추출 및 고성능 액체 크로마토그래피 동시분석)

  • Lee, Kwang-Jin;Ma, Jin-Yeul;Kim, Young-Sik;Kim, Dong-Seon;Jin, Yinzhe
    • Journal of Applied Biological Chemistry
    • /
    • v.55 no.1
    • /
    • pp.61-65
    • /
    • 2012
  • Three major curcuminoids in turmeric (Curcuma longa), curcumin, demethoxycurcumin, and bisdemethoxycurcumin, were efficiently extracted by optimizing extraction condition and simultaneously analyzed and identified using reverse phase high-performance liquid chromatography, thin-layer chromatography, and liquid chromatography-mass spectrometry method. The highest yield of extraction amount 0.279 g, 9.30% was obtained by dipping method with extraction time of 7 h.