• Title/Summary/Keyword: Doping

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Effect of Doping State on Photoresponse Properties of Polypyrrole

  • Choi, Jongwan
    • Elastomers and Composites
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    • v.56 no.4
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    • pp.250-253
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    • 2021
  • Polypyrrole is an organic thermoelectric material which has been receiving extensive attention in recent years. Polypyrrole is applicable in various fields because its electrical properties are controllable by its doping concentration. In this study, the effects of the polypyrrole doping state on its photoresponse were investigated. The degree of doping was controlled by ammonia solution treatment. Then, the chemical structure as a function of the doping states was observed by Raman analysis. Moreover, the photocurrent and photovoltage characteristics for various doping states were measured by an asymmetrically irradiated light source. As the degree of doping increased, the electrical conductivity increased, which affected the photocurrent. Meanwhile, the photovoltage was related to the temperature gradient caused by light irradiation.

The Jurisprudence on Anti-Doping Rule Violation through Review of CAS Awards (CAS의 결정례로 본 도핑 위반 사건의 법리)

  • Kim, Hyun-Sook
    • Journal of Arbitration Studies
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    • v.28 no.1
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    • pp.77-97
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    • 2018
  • The Court of Arbitration for Sport (CAS) has been adjudicating on sports-related disputes since 1984. CAS can be regarded as world supreme court for sports settling down about 4200 cases including doping issues. Doping disputes are generally processed by CAS Appeals division and Anti-Doping Division. An appeal against the decision by sports-related bodies may be filed with CAS Appeals Division. Doping issues concerning Olympic games are on Anti-Doping Division, introduced from 2016 Olympic games and invested with complete authority by IOC. The Award of Maria Sharapova finds a player is responsible if found to have committed any Anti-Doping Rule Violation regardless of his/her intention or fault. It offers detailed jurisprudence on imposing such a specific period of ineligibility in view of the totality of the circumstances. The award of Xinyi Chen also confirms the Strict Liability Rule on anti-doping disputes. The player appealed there could be either accidental contamination of drinks, or doping laboratories' mistakes that affected the test results. But, all of them were rejected. Though dealing with doping disputes in a timely manner is important for seasonal sports events like Olympic games, it is necessary to prepare the acceptable and fair process for the players in the future.

Analysis of Glycerol with Isolation of Endogenous Interferences using "Dilute and Shoot" Strategy and High-Resolution Mass Spectrometry in Human Urine for Antidoping Testing

  • Kim, Yongseok;Min, Hophil;Sung, Changmin;Park, Ju-hyung;Son, Junghyun;Lee, Kang Mi;Kim, Ho Jun;Lee, Jaeick;Kwon, Oh-Seung;Kim, Ki Hun
    • Mass Spectrometry Letters
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    • v.7 no.4
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    • pp.111-115
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    • 2016
  • Glycerol was identified and isolated from endogenous interferences during analysis of human urine using high-resolution mass spectrometry (HRMS) for doping control. Urinary sample preparation was simple; the samples were diluted with an organic solvent and then analyzed using a liquid chromatography-mass spectrometry ("dilute and shoot" method). Although the interfering ion peaks were observed at the similar retention time of glycerol, the inference could be identified by isolation with HRMS and further investigation. Thus, creatinine was identified as the endogenous interference for glycerol analysis and it also caused ion suppression resulting in the decrease of glycerol signal. This study reports the first identification and efficient isolation of endogenous interferences in human urine for "dilute and shoot" method. The information about ion suppression could be novel to prevent overestimation or a false result for antidoping analysis.

LC-MS/MS Method for Simultaneous Analysis of Growth Hormone-Releasing Peptides and Secretagogues in Human Urine

  • Min, Hophil;Han, Boyoung;Sung, Changmin;Park, Ju-Hyung;Lee, Kang Mi;Kim, Ho Jun;Kim, Ki Hun;Son, Junghyun;Kwon, Oh-Seung;Lee, Jaeick
    • Mass Spectrometry Letters
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    • v.7 no.3
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    • pp.55-63
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    • 2016
  • Growth hormone (GH)-releasing peptides (GHRPs) and GH secretagogues (GHSs) are listed in the World Anti-Doping Agency (WADA) Prohibited List. In the present study, we developed and validated a method for the simultaneous analysis of seven GHRPs (alexamorelin, GHRP-1, -2, -4, -5, -6, and hexarelin) and three GHSs (anamorelin, ibutamoren, and ipamorelin) in human urine. Method validation was performed at minimum required performance levels specified by WADA technical documents (2 ng/mL) for all substances, and the method was validated with regard to selectivity (no interference), linearity (R2 > 0.9986), matrix effects (50.0%-141.2%), recovery (10.4%-100.8%), and intra- (2.8%-16.5%) and inter-day (7.0%-22.6%) precisions. The limits of detection for screening and confirmation were 0.05-0.5 ng/mL and 0.05-1 ng/mL, respectively.

Study of P-type Wafer Doping for Solar Cell Using Atmospheric Pressure Plasma (대기압 플라즈마를 이용한 P타입 태양전지 웨이퍼 도핑 연구)

  • Yun, Myoungsoo;Jo, Taehun;Park, Jongin;Kim, Sanghun;Kim, In Tae;Choi, Eun Ha;Cho, Guangsup;Kwon, Gi-Chung
    • Current Photovoltaic Research
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    • v.2 no.3
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    • pp.120-123
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    • 2014
  • Thermal doping method using furnace is generally used for solar-cell wafer doping. It takes a lot of time and high cost and use toxic gas. Generally selective emitter doping using laser, but laser is very high equipment and induce the wafer's structure damage. In this study, we apply atmospheric pressure plasma for solar-cell wafer doping. We fabricated that the atmospheric pressure plasma jet injected Ar gas is inputted a low frequency (1 kHz ~ 100 kHz). We used shallow doping wafers existing PSG (Phosphorus Silicate Glass) on the shallow doping CZ P-type wafer (120 ohm/square). SIMS (Secondary Ion Mass Spectroscopy) are used for measuring wafer doping depth and concentration of phosphorus. We check that wafer's surface is not changed after plasma doping and atmospheric pressure doping width is broaden by increase of plasma treatment time and current.

Method for Screening and Confirming Meldonium in Human Urine by High-Resolution Mass Spectrometry and Identification of Endogenous Interferences for Anti-Doping Testing

  • Kim, Yongseok;Jeong, Dawon;Min, Hophil;Sung, Changmin;Park, Ju-hyung;Son, Junghyun;Lee, Kang Mi;Kim, Ho Jun;Lee, Jaeick;Kwon, Oh-Seung;Kim, Ki Hun
    • Mass Spectrometry Letters
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    • v.8 no.2
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    • pp.39-43
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    • 2017
  • Meldonium is a drug for treating ischemia by expanding the arteries but it can also enhance the performance of sports players. The World Anti-Doping Agency (WADA) has included it in the list of prohibited substances since 2016. Meldonium is one of the challenging substances for anti-doping testing because it is difficult to recover by general liquid-liquid or solid phase extraction due to its permanent charge and high polarity. Therefore, high-performance liquid chromatography (HPLC) is currently used by injecting a diluted urine sample (known as the "dilute-and-shoot" strategy). There is no loss of target compounds in the extraction/cleanup procedure but its high matrix effect could interfere in their separation or detection from the endogenous urinary compounds. We report a single method using high-resolution mass spectrometry that can be used for both screening and confirmation, which follows the "dilute-and-shoot" strategy. In this method, the endogenous compounds' interfering peaks in the mass spectrum are separated at a high resolution of FWHM 140,000, and the results are suitable for substance detection following the WADA guidelines. The interferences in the obtained mass spectrum of the urine matrix are identified as acetylcholine, lysine, and glutamine by further analysis and database searching. Validation of the method is performed in routine anti-doping testing, and the limit of detection is 50 ng/mL. This method uses simple sample preparation and a general reverse phase HPLC column, and it can be easily applied to other substances.

The Doping Profile Modeling of Crystalline Silicon Solar Cell with PC1D simulation (PC1D 시뮬레이션을 이용한 결정질 실리콘 태양전지의 도핑 프로파일 모델링)

  • Choi, Sung-Jin;Yu, Gwon-Jong;Song, Hee-Eun
    • 한국태양에너지학회:학술대회논문집
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    • 2011.11a
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    • pp.149-153
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    • 2011
  • The PC1D is widely used for modeling the properties of crystalline silicon solar cell. Optimized doping profile in crystalline silicon solar cell fabrication is necessary to obtain high conversion efficiency. Doping profile in the forms of a uniform, gaussian, exponential and erfc function can be simulated using the PC1D program. In this paper, the doping profiles including junction depth, dopant concentration on surface and the form of doping profile (gaussian, gaussian+erfc function) were changed to study its effect on electrical properties of solar cell. As decreasing junction depth and doping concentration on surface, electrical properties of solar cell were improved. The characteristics for the solar cells with doping profile using the combination of gaussian and erfc function showed better open-circuit voltage, short-circuit current and conversion efficiency.

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Threshold Voltage Control through Layer Doping of Double Gate MOSFETs

  • Joseph, Saji;George, James T.;Mathew, Vincent
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.10 no.3
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    • pp.240-250
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    • 2010
  • Double Gate MOSFETs (DG MOSFETs) with doping in one or two thin layers of an otherwise intrinsic channel are simulated to obtain the transport characteristics, threshold voltage and leakage current. Two different device structures- one with doping on two layers near the top and bottom oxide layers and another with doping on a single layer at the centre- are simulated and the variation of device parameters with a change in doping concentration and doping layer thickness is studied. It is observed that an n-doped layer in the channel reduces the threshold voltage and increases the drive current, when compared with a device of undoped channel. The reduction in the threshold voltage and increase in the drain current are found to increase with the thickness and the level of doping of the layer. The leakage current is larger than that of an undoped channel, but less than that of a uniformly doped channel. For a channel with p-doped layer, the threshold voltage increases with the level of doping and the thickness of the layer, accompanied with a reduction in drain current. The devices with doped middle layers and doped gate layers show almost identical behavior, apart from the slight difference in the drive current. The doping level and the thickness of the layers can be used as a tool to adjust the threshold voltage of the device indicating the possibility of easy fabrication of ICs having FETs of different threshold voltages, and the rest of the channel, being intrinsic having high mobility, serves to maintain high drive current in comparison with a fully doped channel.

Heavy Doping Effects and Their Application to $N^+ -P$ Solar Cells (강한 도핑의 효과(Heavy Doping Effects)와 $N^+ -P$태양전지에의 응용)

  • 박성호;김충원;한백형
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.24 no.4
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    • pp.631-639
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    • 1987
  • In this paper, we investigate the heavy doping effects theoretically and model the heavy doping parameters as a function of doping concentration. To apply the heavy doping effects to devices, we also analyze n+ -p solar cells in consideration of these effects and investigate the dependence of open circuit voltage on the emitter design parameters. The heavy doping parameters modeled in this paper are in good agreement with experimental results, and the condition of an emitter in the maximum efficiency of solar cells is obtained from the characterization of it.

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Effect of Doping Elements on Superconducting Characteristics in Bi-system Ceramics (Bi계 세라믹에서 초전도체 특성에 미치는 도우핑 원소의 영향)

  • 양승호;박용필;김용주
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.07a
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    • pp.198-203
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    • 2000
  • This paper investigated the effects of doping elements on the Bi-Sr-Ca-Cu-O ceramics. The doping elements can be classified into four groups depending on their superconducting characteristics in the Bi-Sr-Ca-Cu-O structure. The first group of doping elements(Co, Fe, Ni and Zn) substitute into the copper site and can reduce the critical temperatures of the 2223 and 2212 phases. The second group of doping elements(Y and La) substitute into the Ca site and cause the disappearance of the 2223 phase and increase the critical temperatures in the 2212 phase. The third group of doping elements(P and K) have a tendency to decompose the superconducting phase and reduce the optimal sintering temperature. The fourth group of doping elements(B, Si, Sn and Ba) almost unaffected the superconductivity of the 2223 and 2212 phase.

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