• Title/Summary/Keyword: ADS 1.2

Search Result 216, Processing Time 0.025 seconds

Determination of the Langmuir and Temkin Adsorption Isotherms of H for the Cathodic H2 Evolution Reaction at a Pt/KOH Solution Interface Using the Phase-Shift Method

  • Chun Jang-H.;Jeon Sang-K.;Chun Jin-Y.
    • Journal of the Korean Electrochemical Society
    • /
    • v.9 no.1
    • /
    • pp.19-28
    • /
    • 2006
  • The phase-shift method for determining the Langmuir, Frumkin, and Temkin adsorption isotherms ($\theta_H\;vs.\;E$) of H for the cathodic $H_2$ evolution reaction (HER) at a Pt/0.1 M KOH solution interface has been proposed and verified using cyclic voltammetric, differential pulse voltammetric, and electrochemical impedance techniques. At the Pt/0.1 M KOH solution interface, the Langmuir and Temkin adsorption isotherms ($\theta_H\;vs.\;E$), the equilibrium constants ($K_H=2.9X10^{-4}mol^{-1}$ for the Langmuir and $K_H=2.9X10^{-3}\exp(-4.6\theta_H)mol^{-1}$ for the Temkin adsorption isotherm), the interaction parameters (g=0 far the Langmuir and g=4.6 for the Temkin adsorption isotherm), the rate of change of the standard free energy of $\theta_H\;with\;\theta_H$ (r=11.4 kJ $mol^{-1}$ for g=4.6), and the standard free energies (${\Delta}G_{ads}^{\circ}=20.2kJ\;mol^{-1}$ for $k_H=2.9\times10^{-4}mol^{-1}$, i.e., the Langmuir adsorption isotherm, and $16.7<{\Delta}G_\theta^{\circ}<23.6kJ\;mol^{-1}$ for $K_H=2.9\times10^{-3}\exp(-4.6\theta_H)mol^{-1}$ and $0.2<\theta_H<0.8$, i.e., the Temkin adsorption isotherm) of H for the cathodic HER are determined using the phase-shift method. At intermediate values of $\theta_H$, i.e., $0.2<\theta_H<0.8$, the Temkin adsorption isotherm ($\theta_H\;vs.\;E$) corresponding to the Langmuir adsorption isotherm ($\theta_H\;vs.\;E$), and vice versa, is readily determined using the constant conversion factors. The phase-shift method and constant conversion factors are useful and effective for determining the Langmuir, Frumkin, and Temkin adsorption isotherms of intermediates for sequential reactions and related electrode kinetic and thermodynamic data at electrode catalyst interfaces.

Clinical Analysis of 292 Cases of Tic Disorder in Oriental Medicine Clinic (한의원에 내원한 틱장애 환자 292례 증례분석)

  • Chun, Young-Ho;Kim, Won-Ill;Kim, Bo-Kyung
    • Journal of Oriental Neuropsychiatry
    • /
    • v.20 no.1
    • /
    • pp.119-146
    • /
    • 2009
  • Objectives : In this study, patients with tic disorders who visited an Oriental medicine clinic were examined for their demographic characteristics, characteristics of symptoms, relation to Attention-deficit Hyperactivity Disorder(ADHD) and peculiarity according to various variables such as motor and vocal tics. Methods : After surveying 292 patients who visited an Oriental medicine clinic with tic symptoms as main complaints for 17 months, SAS 9.1, a statistical program was used for statistical analysis. Results : 1. The BMI of male tic patients was significantly higher than female ones and it was similar to or higher than the normal group. 2. Patients who are eldest children were 1.7 times higher than those who are not eldest ones. 3. The most usual case of motor tics was the eye blink and the most one of vocal tics was a dry cough. 4. There was no significant difference between male and female patients for all symptoms of motor and vocal tics, but male patients had significantly more obsessions related to tics than female ones. 5. There was no significant difference in the age of initial occurrence of Transient tic disorder(TTD), Chronic tic disoder(CTD) and Tourette's disorder(TD). 6. For the general disorder of a tic and Conners' ADHD rating scale, there was no significance in TTD, CTD and TD. 7. 66% out of the total subjects of 197 cases were found to score more than 65 points in more than 1 items among 8 items such as the time, hearing, wrong alarm, mean response time and standard deviation in the response time, etc. of the ADHD diagnosis system(ADS). 8. The eye blink among motor tics was shown mainly by patients under 10 years old and the frown, movement of the head, shrug and movement of the arms were shown mainly by 11-19 years old patients. Conclusions : For the number, frequency, seriousness and inconvenience in life of tics, TD showed a significantly higher result than TTD and CTD.

  • PDF

Kinetics and Mechanism of the Oxidation of Sulfur Dioxide on Nickel Oxide-${\alpha}$-Ferric Oxide System (산화니켈-${\alpha}$ 형 산화철 상에서 이산화황의 산화 반응메카니즘)

  • Kyu Yong Lee;Yong Rok Kim;Sung Han Lee
    • Journal of the Korean Chemical Society
    • /
    • v.27 no.3
    • /
    • pp.183-188
    • /
    • 1983
  • The catalytic oxidation of $SO_2$ has been investigated in the presence of vacuum-activated 10 mol % Ni-doped ${\alpha}-Fe_2O_3$ under various partial pressures of $SO_2\;and\;O_2$ at temperatures from 320 to $440{\circ}C$. Over the temperature range $320{\sim}440{\circ}C$, the activation energy is 13.8 $kcal{\cdot}mol^{-1}$. The oxidation rates have been correlated with 1.5 order kinetics; first order with respect to $SO_2$ and 0.5 order with respect to $O_2$. From the kinetic data and conductivity measurements, the adsorption, oxidation mechanism of $SO_2$ and the defect structure of vacuum-activated 10 mol % Ni-doped {\alpha}-Fe_2O_3$ are suggested. $O_2\;and\;SO_2$ appear to be adsorbed essentially as ionic species. Two surface sites, probably an $O^{2-}$ lattice and an oxygen vacancy which is induced by Ni-doping, might be required to adsorb $SO_2\;and\;O_2$. The conductivity measurements and kinetic data indicate that the adsorption process of $SO_2\;{(SO_2+O^{2-}}_{(latt)}{\rightleftharpoons}{{SO_3}^-}_{(ads)}+e')$ is the rate-determining step.

  • PDF

Determination of Adsorption Isotherms of Hydroxide ata Platinum Electrode Interface Using the Phase-Shift Method and Correlation Constants

  • Chun, Jin-Y.;Chun, Jang-H.
    • Journal of the Korean Electrochemical Society
    • /
    • v.10 no.3
    • /
    • pp.219-228
    • /
    • 2007
  • The phase-shift method and correlation constants, i.e., the electrochemical impedance spectroscopy (EIS) techniques for studying linear relationships between the behaviors (${\varphi}\;vs.\;E$) of the phase shift ($0^{\circ}{\leq}-{\varphi}{\leq}90^{\circ}$) for the optimum intermediate frequency and those (${\theta}\;vs.\;E$) of the fractional surface coverage ($1{\geq}{\theta}{\geq}0$), have been proposed and verified to determine the Langmuir, Frumkin, and Temkin adsorption isotherms (${\theta}\;vs.\;E$) of H for the cathodic $H_2$ evolution reaction (HER) at noble and transition-metal/aqueous solution interfaces. At the Pt/0.1 MKOH aqueous solution interface, the Langmuir, Frumkin, and Temkin adsorption isotherms (${\theta}\;vs.\;E$), equilibrium constants ($K=5.6{\times}10^{-10}\;mol^{-1}\;at\;0{\leq}{\theta}<0.81$, $K=5.6{\times}10^{-9}{\exp}(-4.6{\theta})\;mol^{-1}\;at\;0.2<{\theta}<0.8$, and $K=5.6{\times}10^{-10}{\exp}(-12{\theta})\;mol^{-1}\;at\;0.919<{\theta}{\leq}1$, interaction parameters (g = 4.6 for the Temkin and g = 12 for the Frumkin adsorption isotherm), rates of change of the standard free energy ($r=11.4\;kJ\;mol^{-1}$ for g=4.6 and $r=29.8\;kJ\;mol^{-1}$ for g=12), and standard free energies (${\Delta}G_{ads}^0=52.8\;kJ\;mol^{-1}\;at\;0{\leq}{\theta}<0.81,\;49.4<{\Delta}G_{\theta}^0<56.2\;kJ\;mol^{-1}\;at\;0.2<{\theta}<0.8$ and $80.1<{\Delta}_{\theta}^0{\leq}82.5\;kJ\;mol^{-1}\;at\;0.919<{\theta}{\leq}1$) of OH for the anodic $O_2$ evolution reaction (OER) are also determined using the phase-shift method and correlation constants. The adsorption of OH transits from the Langmuir to the Frumkin adsorption isotherm (${\theta}\;vs.E$), and vice versa, depending on the electrode potential (E) or the fractional surface coverage (${\theta}$). At the intermediate values of ${\theta}$, i.e., $0.2<{\theta}<0.8$, the Temkin adsorption isotherm (${\theta}\;vs.\;E$) correlating with the Langmuir or the Frumkin adsorption isotherm (${\theta}\;vs.\;E$), and vice versa, is readily determined using the correlation constants. The phase-shift method and correlation constants are accurate and reliable techniques to determine the adsorption isotherms and related electrode kinetic and thermodynamic parameters. They are useful and effective ways to study the adsorptions of intermediates (H, OH) for the sequential reactions (HER, OER) at the interfaces.

침치료에 대한 환자진료 평가 프로그램-독일 보험회사들의 침효과에 대한 검증-

  • Melchart, Dieter
    • Journal of Pharmacopuncture
    • /
    • v.6 no.1
    • /
    • pp.33-34
    • /
    • 2003
  • 배경: 독일 의사와 보험회사 위원회 (The German Board of Physicians and Insurance Companies:Bundesausschuss der Arzte und Krankenkassen)가 앞으로 일부 적응증에 대한 침치료에 대해 공적 보험회사가 보험료를 지급해야 할 지에 대한 추가 결정을 하기 위해 침의 효과를 평가하기로 했다. 목적: 1) 침치료가 편두통의 예방, 긴장성 두통, 요통, 무릎과 고관절의 골관절염치료에 대조군 침치료보다 효과가 있는지 검증 2) 침치료가 편두통의 예방적 치료에 표준 약물 치료와 비슷하게 효과가 있는지 검증 3) 보건의료 서비스체계 안에서 주어진 조건에 대한 일상적 침치료의 질적인 부분을 서술하고, 안전성을 평가하며, 다른 침술학파간의 임상결과의 차이와 비용의 효용적 활용부분을 평가한다. 4) 위의 적응증에 해당하는 모든 임상실험연구를 찾아내어 기존의 고찰내용을 갱신한다. 방법: 1) 무작위 표본추출 임상 실험, 침치료, 거짓침 치료, 대기자 명단 대조군, 출발시점 4주, 28주 관찰 2) 무작위 표본추출 임상 실험, 침치료, 표준약물치료 대조군, 츨발시점 4주, 28주 관찰 3) 전향적 다중 의료기관 관찰 연구, 두 가지 다른 자료를 활용하여서, 치료 결과를 침 시술자에 의한 모든 환자 평가 자료와, 열 두 명의 환자 가운데 한 명의 환자로부터 직접 받은 평가 자료 (관찰 출발시점, 치료 출발 시점, 치료 시작 후 6 개월) 실험공간: 1) and 2) 높은 수준의 수련을 한 침 시술 의사가 시술하는 병원이나 일차 진료기관의 외래. 3) 보건 의료 서비스내 저급의 침 시술 의사 (140 시간 수강, 학점 이수 필수) 참가자: 1) $4{\times}320$ 편두통의 예방, 긴장성 두통, 요통, 무릎과 고관절의 골관절염 환자 2) 480 편두통 환자(긴장성 두통 환자 추가적) 3) 약 500,000 환자, 2년 반 동안: 대략 한 적응증 당 10,000 환자 치료법: 모든 침치료 자리는 체침만 허용함. 1) 진짜 침은 학파의 지침에 따른 심자, 거짓 침은 비특이적 자리의 표피만 찌르는 자침 (12-15회, 8주): 대기자 대조군은 12주 동안에 아무 치료도 받지 않는다. 2) Group 1(N=240): 최대 15회 치료, 12주 동안: Group II (N=240) 투약 Proponolol (80-240mg), Metoprolol (100-200mg) or Flunarizin (5-10mg) 하루, 16주 이상 3) 치료회수와 침자리의 선정은 참가자가 결정 주된 임상 결과 지표: 1) 군 간의 치료 전 및 치료 진행 도중 4주 마다의 두통을 느낀 날 수의 차이 (평균 혹은 이상의 편두통이나 긴장성 두통) 2) 요통환자 군간의 기능을 측정하는 FFbH-R (Funktionsfragebogen Hannover) 비교 3) 관절염 환자의 군간 WOMAC 지표 비교 4) 군 간의 24주 동안 두통을 느낀 날 수의 차이(평균 혹은 이상의 편두통이나 긴장성 두통) 5) 적응증, 부작용, 성공율에 대한 거시적 평가, 사용한 침수, 환자의 만족도, SES(?). ADS(?) 통증 장애 지표(PDI), 삶의 질 지표(SF36). 예비 결과 위의 결과가 큰 관찰 연구에 초점을 맞추면서 소개될 것임.

Modification of CPW Pad Design for High fmax InGaAs/InAlAs Metamorphic High Electron Mobility Transistors (높은 $f_{max}$ 를 갖는 InGaAs/InAlAs MHEMT 의 Pad 설계)

  • Choi, Seok-Gyu;Lee, Bok-Hyung;Lee, Mun-Kyo;Kim, Sam-Dong;Rhee, Jin-Koo
    • Proceedings of the IEEK Conference
    • /
    • 2005.11a
    • /
    • pp.599-602
    • /
    • 2005
  • In this paper, we have performed a study that modifies the CPW Pad configurations to improve an $f_{max}$ characteristic of metamorphic HEMT. To analyze the CPW Pad structures of MHEMT, we use the ADS momentum simulator developed by $Agilent^{TM}$. Comparing the employed structure (G/W = 40/100 m), the optimized structure (G/W = 20/25 m) of CPW MHEMT shows the increased $S_{21}$ by 2.5 dB, which is one of the dominant parameters influencing the $f_{max}$ of MHEMT. To compare the performances of optimized MHEMT with the employed MHEMT, DC and RF characteristics of the fabricated MHEMT were measured. In the case of optimized CPW MHEMT, the measured saturated drain current density and transconductance $(g_m)$ were 693 mA/mm and 647 mS/mm, respectively. RF measurements were performed in a frequency range of $0.1{\sim}110$ GHz. A high $S_{21}$ gain of 5.5 dB is shown at a millimeter-wave frequency of 110 GHz. Two kinds of RF gains, $h_{21}$ and maximum available gain (MAG), versus the frequency, and a cut-off frequency ($f_t$) of ${\sim}154$ GHz and a maximum frequency of oscillation ($f_{max}$) of ${\sim}358$ GHz are obtained, respectively, from the extrapolation of the RF gains for a device biased at a peak transconductance. An optimized CPW MHEMT structure is one of the first reports among fabricated 0.1 m gate length MHEMTs.

  • PDF

Effect of PCB Switching Noise on Radiated Emission from Enclosure Aperture (PCB에 인가된 스위칭 잡음이 함체 개구 방사에 미치는 영향)

  • Jang, Hyoung-Seok;Lee, Soong-Keun;Kim, Eun-Ha;Ryu, Seung-Real;Lee, Jae-Hyun;Park, Dong-Chul
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.22 no.1
    • /
    • pp.67-75
    • /
    • 2011
  • This paper investigates the radiated emission from the enclosure aperture, when the enclosure contains a 4-layer PCB and the PCB is driven by a pulse train additive with the switching noise from an active device. Radiated emission characteristics with and without switch noise cases, respectively, are analyzed by changing the PCB location and the slot direction. The equivalent circuit of a DC-DC converter is used to simulate the switching noise of active device. Also, MWS simulation results are directly connected to the ADS simulator as a 2-port block. The simulated results are compared with the measured ones.

A Study on Clothing Benefit and Its Related Variables of Male and Female Consumers in Their Twenties (20대 남녀소비자의 의복추구혜택과 관련변인에 관한 연구)

  • Ha, Jong-Kyung;Kim, Ju-Hee
    • Korean Journal of Human Ecology
    • /
    • v.18 no.4
    • /
    • pp.879-889
    • /
    • 2009
  • The purpose of this study was to analyze the dimensions of clothing benefits sought of male and female consumers in their twenties. It also aimed to investigate the demographic characteristics associated with customers types and the relationship among the related variables by the consumers types. The data were analyzed by factor analysis, one-way ANOVA, Duncan test, cluster analysis, and $X^2$-test. The results of this study are as follows: 1) The clothing benefits consisted of five factors, which were the pursuit of style, individuality, popular brand, vogue, and practicality. Based on these five factors, respondents were classified into four consumer types, which were style-and-trend-oriented, practicality-oriented, popular brand-oriented, and fashion indifference consumers. 2) In terms of the demographics, there were significant differences in age, gender, and total income among the consumer types of clothing benefits. 3) There was a significant difference in single brand loyalty in terms of the consumers types of clothing benefits. The popular brand-oriented group showed the highest mean in the single brand loyalty, while the practicality-oriented group did the lowest. 4) There were significant differences in the selection of the stores among consumers types of clothing benefits. Specifically, the style-and-trend-oriented group the most selected department stores, while practicality-oriented group chose fashion outlets or online shopping malls the most. Additionally, in terms of the information sources, the style-and-trend-oriented group the most frequently used magazine ads, while the popular-brand-oriented group preferred commercials on TV or radio, direct mail, or flyers from department stores. On the other hand, the fashion indifference group the most frequently used mass media.

Analysis of Newspaper Articles on Korean Style Medicinal Tea (한방차에 관한 신문기사 내용 분석)

  • Park, Soyeon;Lee, Sanglock;Chae, Seungbum;Lee, Sangjae
    • Journal of Society of Preventive Korean Medicine
    • /
    • v.21 no.2
    • /
    • pp.95-103
    • /
    • 2017
  • Objectives : The aim of this study is to analyze the news contents of Korean style medicinal tea and investigate how it is portrayed in the consumer market. Methods : Total of 355 articles are selected by inputting "Korean style medicinal tea" and analyzed; 108 articles for 2013, 107 articles for 2014, 140 articles for 2015. Results : 175 different tea were found from Jan. $1^{st}$ 2013 to Dec. $31^{st}$ 2015, with ginger tea the most frequently covered for 68 times. Among 175 tea, 117 had one ingredient and 58 had more than one ingredient. The most frequently covered category was "Disease and Health Promotion" followed by "Commercial Ads", "Korean style medicinal tea Culture", and others. From 355 articles, 188 provided the information on the efficacy of Korean style medicinal tea, 88 presented the pharmacological activity, 84 addressed the recipe, 80 explained the taste, and 31 included ancient literature. The most frequently covered tea were ginger tea, omija tea, gugija tea, jujube tea, mogwa tea. Autumn and winter had 109 articles, spring had 89, and summer had 86. Conclusions : This study showed the potential of Korean style medicinal tea as a successful future content. Most of the articles about Korean style medicinal tea contained information about the efficacy but practical information such as the recipe and drinking method were not addressed much. Therefore, future study is needed to investigate additional information about Korean style medicinal tea.

Developing the Korean National Archaeological Data Digital Archive: An Exploratory Study (국가 고고학 데이터 디지털 아카이브 개발을 위한 연구)

  • Rhee, Hea Lim
    • Journal of Korean Society of Archives and Records Management
    • /
    • v.18 no.2
    • /
    • pp.1-28
    • /
    • 2018
  • Because archaeological artifacts are often destroyed during physical excavation, the data archaeologists gather in the field is rich with research potential. Few in Korea have paid attention to digital archives for archaeological data or argued for their development. This paper considers the significance and necessity of archaeological data and digital archives for its preservation and access. It also raises awareness of the need to develop a Korean national archaeological data digital archive. The paper first overviews the nature of the archaeological discipline, data, and digital archives. Then it investigates well-known, global cases involving digital archiving of archaeological data. Based on these foundations, the paper discusses principal and prior challenges to developing a Korean national archaeological data digital archive.