• 한국지반공학회지:지반
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• 제13권6호
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• pp.123-138
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• 1997

중금속으로 오염된 점성토의 정화에 대한 electrokinetic기술의 효율을 연구하기 위하여 포화 해성점토를 납으로 오염시켜 전기삼투시험을 수행하였다. 이를 위하여 실험조건으로서 납의 오염농도 500, 5,000, 50,000mg/kg, 공급전류 10, 50, 100mA, 가동시간 5, 15, 30일 및 3가지의 효율 향상기법을 적용하였다. 유입수와 유출수의 pH, 전기삼투유량 및 전기전도도를 시험중에 측정하고 또 시험 완료후에 공시체전 길이에 걸쳐 pH및 잔존 납농도를 측정하여 제시하였다. 시험결과에 의해서 electrokinetic 기술이 효과적인 방법이라는 결론을 얻었다. 또한 음극에 침강된 수산화납을 용해시키기위해 초산을 가하게 되면 정화효율이 향상된다는 사실을 알 수 있었다.

• 한국환경보건학회지
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• 제29권2호
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• pp.62-68
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• 2003

Differential pulse voltammetry (DPV) using nafion-coated glassy carbon electrodes modified with Tetren(tetraethylene pentamine)-glycerol showed sensitivity for determining lead (II) at low concentration. The Lead (II) was accumulated on the electrode surface by the formation of the complex in an open circuit, and the resulting surface was characterized by medium exchange, electrochemical reduction, and differential pulse voltammetry. Various experimental parameters, such as the composition of modifier, preconcentration time, pH of electrolyte (0.1 M acetate buffer), and parameters of differential pulse voltammetry, were optimized. The initial potential was applied for 50 s, the electrode was scanned from -0.9 to -0.3 V, and the anodic peak current was measured at -0.604 V $\pm$ 0.015 V (vs. Ag/AgCl). The calibration plot was obtained in the range 1.0$\times$10$^{-8}$ M~l.0$\times$10$^{-6}$ M with pH 4.5 buffer solution. The detection limit (3$\sigma$) it as low as 5.0$\times$ 10$^{-9}$ M. This method is applied to the determination of lead(II) in a certified reference material and the result agrees satisfactorily with the certified value.

• Toxicological Research
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• 제29권4호
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• pp.293-298
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• 2013

A method of detecting lead was developed using square wave anodic stripping voltammetry (SWASV) with DNA-carbon nanotube paste electrode (CNTPE). The results indicated a sensitive oxidation peak current of lead on the DNA-CNTPE. The curves were obtained within a concentration range of 50 $ngL^{-1}-20mgL^{-1}$ with preconcentration time of 100, 200, and 400 sec at the concentration of $mgL^{-1}$, ${\mu}gL^{-1}$, and $ngL^{-1}$, respectively. The observed relative standard deviation was 0.101% (n = 12) in the lead concentration of 30.0 ${\mu}gL^{-1}$ under optimum conditions. The low detection limit (S/N) was pegged at 8 $ngL^{-1}$ ($2.6{\times}10^{-8}M$). Results showed that the developed method can be used in real-time assay in vivo without requiring any pretreatment and pharmaceutical samples, and food samples, as well as other materials requiring water source contamination analyses.

• Korean Chemical Engineering Research
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• 제56권6호
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• pp.779-783
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• 2018

본 연구에서는 차량용 12 V 납축전지로 주로 사용되는 VRLA (Valve regulated lead acid) 배터리의 충/방전 특성과 노화에 따른 이의 변화를 수학적으로 모델링하였다. 기존에 리튬 이온 배터리의 거동 예측에 주로 이용되어 왔던 수학적 모델링 기법을 상용 70 Ah VRLA 배터리에 적용하였다. 정전류 충/방전에 따른 전압의 변화를 모델링 결과와 비교하였다. 비교 결과로부터 사용된 수학적 모델이 납축전지에도 높은 정확도로 적용될 수 있음을 알 수 있었다. 또한 이를 이용하여 납축전지의 노화를 예측할 수 있음을 확인하였다.

• 대한방사선기술학회지:방사선기술과학
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• 제44권6호
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• pp.615-621
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• 2021

In the medical field, radiation provides information for the diagnosis and treatment of diseases. As the use of radiation increases and the risk of exposure increases, interest in radiation protection is also rapidly increasing. Lead shielding material is mainly used, which has a risk of lead poisoning and absorption into the body. Tungsten mixed filament shielding sheets were fabricated with a size of 70 × 70 mm and a thickness of 1, 2, and 4 mm by using a 3D printer. In the general shooting experiment, the thickness of the shielding sheet is 1 ~ 5mm, the tube voltage is 60, 80, 100, 120 kVp and the tube current is 20, 40 mAs. In general photography, Tungsten showed better shielding rate compared to Brass, Copper, and Lead protective tools under all irradiation conditions, and in particular, Tungsten 5 mm showed 100% shielding rate. The 3D-printed tungsten mixed filament shielding is expected to be used as a new shield that can replace the existing lead protection tools as it shows a better shielding rate than the existing lead protection tools in Radiography.

• Current Photovoltaic Research
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• 제11권1호
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• pp.18-26
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• 2023

Tin perovskite solar cells have attracted a lot of attention due to their potential to address the toxicity of lead, which is the biggest barrier to commercialization of perovskite solar cells. Unlike other lead-free perovskite, tin perovskite have a direct bandgap, which is suitable for use as light harvesting, and relatively good stability, which has led to a lot of attention. Since the first tin perovskite solar cell was reported in 2014, it has achieved an impressive power conversion efficiency of 14.81%. However, this efficiency is still low compared to that of lead perovskite solar cells, and the stability of tin perovskite solar cells is also an issue that needs to be addressed. In this review, we will discuss the basic properties of the tin atom in comparison to the lead atom, and then discuss the crystal structure, phase transition, and basic properties of tin perovskite. We will then discuss the advantages, applications, challenges, and strategies of tin perovskite, In particular, we will focus on how to prevent the oxidation of tin, which is arguably the biggest challenge for using tin perovskite solar cells. At the end, we summarize the key factors that need to be addressed for higher efficiency and stability, emphasizing what is needed to commercialize tin perovskite solar cells.

• 한국전기전자재료학회논문지
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• 제18권4호
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• pp.370-374
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• 2005

AC loss of a superconducting conductor has a strong influence on the economic viability of a superconducting fault current limiter, which offers an attractive means to limit short circuit current in power systems. Therefore, the AC loss characteristics in several fault current limiting elements of a coil type have been investigated experimentally. The test result shows that AC losses measured in the fault current limiting elements depend on arrangement of a voltage lead. The AC loss of a bifilar coil is smallest among the fault current limiting elements of the coil type. The measured AC loss of the bifilar coil is much smaller than that calculated from Norris's elliptical model. However, the loss measured in a meander, which is frequently used in a resistive fault current limiter, agrees well to the theoretical one.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제55권8호
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• pp.396-402
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• 2006

Even the case DC circuit Breaker have good quality for interruption of high current like heavy load current, short-circuit current, the verification for small current breaking capability of circuit breaker should be performed. It comes from the reason DC small current breaking failure can be lead to break out second heavy fault condition and in the long run substation shutdown. In this paper, we can find the characteristics of DC small current and international test standard discription about small current breaking and one of the proper solution to get over it.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2006년도 High Temperature Superconductivity Vol.XVI
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• pp.26-26
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• 2006

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2003년도 춘계학술발표대회 요약집
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• pp.428.2-428.2
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• 2003