• 대한화학회지
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• 제57권3호
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• pp.316-321
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• 2013

Electrocoagulation (EC) technique is applied for the treatment of wastewater containing heavy metals ions such as nickle (Ni), lead (Pb) and cadmium (Cd) by using sacrificial anodes corrode to release active coagulant flocs usually aluminium or iron cations into the solution. During electrolytic reactions hydrogen gas evolve at the cathode. All the experiments were carried out in Batch mode. The tank was filled with synthetic wastewater containing heavy metals and efficiency of electro-coagulation in combination with aluminum and iron electrodes were investigated for removal of such metals. Several parameters, such as contact time, pH, electro-coagulant concentration, and current density were optimized to achieve maximum removal efficiency (%). The concentrations of heavy metals were determined by using Atomic Absorption Spectroscopy (AAS). It is found that the electro-coagulation process has potential to be utilized for the cost-effective removal of heavy metals from wastewater specially using iron electrodes in terms of high removal efficiencies and operating cost.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.407-408
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• 2005

High surface area electrodes for aluminum electrolytic capacitors are produced by AC electrochemical processes. Optimization of crystallographic etch pit growth on aluminium during AC etching of cathode film for aluminium as electrolytic capacitor has been established. In this work, we present the observations of pit distributions by galvanostatic measurements. The effects of electrolyte concentration, current density, frequency, various pre-treatments and etching time have been studied. The specimen was pretreated in 0.5M NaOH and 1M HCl at $40\sim60^{\circ}C$, and transferred into a cell containing 1M HCl, then various mol $H_2SO_4$ etchant was added. Pit size distributions were determined with scanning electron microscopy (SEM).

• Environmental Engineering Research
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• 제24권3호
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• pp.521-528
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• 2019

Electrochemical method was used for the fracturing flow-back fluid treatment in Guangyuan oilfield. After performing electrolysis, we found that the amount of $H_2$ gas produced by electrode was closely related to the combination mode of electrodes and electrode materials. Using an aluminium electrode resulted in a large $H_2$ production of each electrode combination, whereas inert anode and cathode materials resulted in low $H_2$ production. Then, the relationship between the gas production of $H_2$ and the treatment efficiency of fracturing flow-back fluid in Guangyuan oilfield was studied. Results showed that the turbidity removal and decolourisation rates of fracturing flow-back fluid were high when $H_2$ production was high. If the $H_2$ production of inert electrode was large, the energy consumption of this inert electrode was also high. However, energy consumption when an aluminium anode material was used was lower than that when the inert electrode was used, whereas the corresponding electrode combination production of $H_2$ was larger than that of the inert electrode combination. When the inert electrode was used as anode, the gas production type was mainly $O_2$, and $Cl_2$ was also produced and dissolved in water to form $ClO^-$. $H_2$ production at the cathode was reduced because $ClO^-$ obtained electrons.

• 대한소아치과학회지
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• 제23권3호
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• pp.717-728
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• 1996

The effects of electro-acupuncture on the pain threshold and the amplitude of dEMG(di-gastric EMG) evoked by the noxious electric stimulation on teeth and gingiva in dogs were studied. Experiments were carried out with 10 dogs weighing 5-8kg. Each animal was anestheticed with Entobar given intraperitoneally in an initial dose of 30mg/kg. Maintenance dose of 5mg/kg/hr was given through a cannula, in the femoral vein, as required to keep up light anesthesia. Bipolar stimulating wire electrodes, 0.1mm in diameter, insulated except for tips, were inserted into the upper canine and palatal gingiva. Rectangular aluminium plate electrodes (15$\times$5mm) were placed on acupuncture points, called Yin-Hsiang, located at both sides of the upper jaw. Rectangular biphasic current pulses of 2Hz, with a $250{\mu}sec$ duration, were delivered for 15 minutes. The dEMG activities were recorded from the anterior belly of the digastric muscle(one of the jaw opening muscles) using bipolar wire electrodes. The magnitude of the jaw opening reflex at different intensties of electro-acupuncture(1volt 4volt and 10volt) was estimated by averaging the 30 superimposed dEMGs recorded on an oscilloscope and audiomonitor. Data were analysed statistically with ANOV A and paired t-test. The obtained results were as follows: 1. Pain thresholds were increased 7.7 %, 15.4 %, 17.3 % in the teeth and 11.1 %, 19.0 %, 25.4 % in the gingiva as the intensities of electro-acupuncture increased incrementally. 2. Amplitudes of dEMG were decreaed 8.3%, 22.4%, 27.4% in the teeth and 9.8%, 36.5%, 42.2 % in the gingiva as the intensities of electro-acupuncture increased incrementally. 3. Inhibition of pain responses by the electroacupuncture was more effective in the gingiva than in the teeth.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.966-969
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• 2003

Thin film capacitors with Al-Polymer-Al sandwich structure were fabricated. The bottom and top aluminium (Al) electrodes were deposited by vacuum evaporation and copper phthalocyanine (CuPc), polyaniline-emeraldine base (Pani-EB) and cobalt phthalocyanine/polyaniline - emeraldine base (CoPc /Pani-EB) blend films (which can be used as buffer hole injection layer in OLEDs) were deposited by spin coating technique. X-ray diffractograms indicated amorphous nature of the polymer films whose thicknesses were measured by capacitance and Rutherford Backscattering Spectrometry (RBS) methods. AC conduction studies revealed that the conduction mechanism responsible in these films is variable range hopping of polarons. From D.C conduction studies, it is observed that, the nature of conduction is ohmic in the lower fields and at higher fields the dominating D.C conduction is of Poole-Frenkel type.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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• pp.1515-1517
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• 2001

In this work the electrical characteristics of organic TFTs with the semiconductor-insulator interfaces have been interested. Pentacene is used as an active semiconducting layer. The semiconductor layer of pentacene was thermally evaporated in vacuum at a pressure of about $2{\times}10^{-6}$ Torr and at a deposition rate of 0.3$\AA$/sec. Aluminium and gold were used for gate and source/drain electrodes. before pentacene is deposited on the insulator, the gate dielectric surfaces of two samples were rubbed with lateral and perpendicular to direction of the channel length respectively.

• Membrane and Water Treatment
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• 제5권4호
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• pp.251-263
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• 2014

The study contributes in the treatment of waste generated by the textile complex cotton of Draa Ben Khedda, Algeria. The azo dye "Direct Red Solophenyle 4GE" represents the base particle of the discharges and electrocoagulation with nanofiltration are used as a means of treatment. The solar photovoltaic is suitable for electrochemical process to reduce the energy cost. Several study parameters are considered in this work. The electrocoagulation batch gives the best reduction 37% for a dye concentration of 7.21 mg/L ($[NaCl]_{added}$=1g/L; $j=25.2mA/cm^2$). Coupling methods (electrocoagulation-nonofiltration) gives a complete discoloration rejecting concentration 52.4 mg/L (pHi = 7.6, $[NaCl]_{added}$=3g/L, $j=2.13mA/cm^2$). The result shows the coupling efficiency with a reduced amount of resulting slurry at the end of treatment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1590-1592
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• 2002

In this work the electrical characteristics of organic TFTs using organic insulator and flexible polyester substrate have been investigated. Pentacene and PVP(polyvinylphenol) are used as an active semiconducting layer and dielectric layer respectively. Pentacene was thermally evaporated in vacuum at a pressure of about $1{\times}10^{-6}$ Torr and at a deposition rate of $0.5{\AA}$/sec, and PVP was spin-coated. Aluminium and gold were used for gate and source/drain electrodes. 0.1mm thick flexible polyester substrate was used instead of glass or silicon wafer.

• 한국전자파학회논문지
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• 제13권10호
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• pp.1048-1053
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• 2002

본 논문에서는 2 GHz 대역의 격자형 및 평형 구조를 가지는 박막공진 여파기를 설계, 제작하고 분석하였다. 단위공진자의 앞전물질은 AIN를 사용하였고, 전극도체로는 백금을 사용하였으며, 하부도체와 기판사이에 공기층이 있는 구조로 제작되었다. 제작된 여파기들은 크기가 작고 낮은 삽입손실과 격자형의 경우 약 15 dB, 평형 구조의 경우 약 30 dB 정도의 선택도를 가진다. 격자형 및 평형 구조는 사다리형 구조와 같이 실리콘 기판위에 제작되었으며, 사다리형 구조에 비해 넓은 대역폭을 가지며 평형구조의 경우 이외의 튜닝과정 없이 RF 여파기로 사용될 수 있다.

• 조명전기설비학회논문지
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• 제12권2호
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• pp.85-90
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• 1998

본 논문에서는 AC 전압 하에서 자유 도전성 금속이물 혼입에 의한 SF6 가스로 압축된 GIS의 절연특성에 관하여 연구하였다. GIS 내에서 자유 도전성 금속이물이 혼입되면 절연파괴 전압을 낮추는 결정적인 역할을 할 수 있으므로, 금속이물의 재질과 크기에 따른 부상전계 및 절연파괴전압을 측정하였다. 구리, 철, 알루미늄의 선형 금속이물에서의 부상전계 계산값과 측정값을 비교, 분석하였다. 압축된 $SF_6$ 가스로 절연된 동축원통전극간에 금속이물의 혼입될 경우의 절연파괴전압은 금속이물의 없을 때보다 낮게 나타났으며, 금속이물의 재질과 크기에 상당히 의존하였다. 따라서 자유도전성 금속이물은 GIS의 절연파괴 특성에 매우 중요한 요소로 작용함을 알 수 있었다.