• 한국대기환경학회지
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• 제27권4호
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• pp.379-386
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• 2011

Catalyst-assisted plasma system with a DBD (Dielectric Barrier Discharge) reactor was used to remove hydrogen sulfide, which is one of the odorous species in this study. The ${\gamma}-Al_2O_3$ and ${\beta}$-Zeolite catalysts impregnated by Ag, Cu and Mn species were employed as catalysts and their $H_2S$ removal characteristics under plasma irradiation were investigated. From the experimental study, we found that the $H_2S$ removal efficiency increases with decreasing space velocity in the system and increasing specific input energy. Furthermore, ${\beta}$-Zeolite catalysts are efficient to remove $H_2S$ than ${\gamma}-Al_2O_3$ catalysts. Especially, the catalysts impregnated by Ag have higher removal efficiency than other catalysts (Cu, Mn).

• 한국표면공학회지
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• 제52권6호
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• pp.326-333
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• 2019

The microporous carbon derived from PVDC-resin by a simple heat-treatment under an inert atmosphere exhibits a reasonable specific capacitance for a supercapacitor's electrode. However, the capacitance was rapidly decreased at high charge/discharge rate. The micropores present in an electrode surface hinder the entrance of an electrolyte ion onto the entire surface. To induce the meso-sized pores during the carbonization of PVDC-resin, Mg(OH)₂ was utilized as a hard template. The porous carbon made from the mixture of PVD-Cresin and Mg(OH)₂ include mesopores as well as micropores. The induced mesopores does not homogeneously distributed on the entire surface of the synthesized carbon. The PVDC-resin and Mg(OH)₂ are dissolved in the dimethylformamide for the hard template to evolve the pores on the synthesized carbon uniformly. The carbon made from PVDC-resin with solvent and a hard template contains mostly mesopores resulting in the high power performance. The reduced amount of solvent in the precursor derives the carbon with high specific surface area and high power density.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.2022-2024
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• 2005

Electrical double-layer capacitor (EDLC) is an electrochemical energy storage device in which electric charges only accumulated by a pure electrostatic attraction force are stored on the electrolyte-electrode interface in a form of double layer and separated by the electrolyte. The composite was prepared by mixing nanosize $TiO_2$ and activated carbon through a means of ultrasonic vibration in ethanol solution for 30 min in various mass ratios of $AC:TiO_2$ to form activated carbone-semiconducting oxide composites. Either 1.0 M $LiClO_4/EC-DEC$ or $Et_4NBF_4$/EC-DEC was used as the electrolyte. It was found that with modification of $TiO_2$, the specific capacitance of activated carbon measured at $1mA/cm^2$ was increased from 40 to 50 F/g. This method is unique in comparison the conventional method because it uses semiconducting TiO2 other than electrochemically active materials such as $RuO_2$. The increase in specific capacitance could be attributed to the decrease in electric polarization, caused by the introduction of $RuO_2$.

• 동의신경정신과학회지
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• 제30권3호
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• pp.119-128
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• 2019

Objectives: This study suggests the application of philosophical counseling in the clinical field of Korean medicine and analyze the specific case. Methods: Through the analysis of coexisting factors of Korean medicine and philosophical counseling, we establish the area of philosophical counseling that Korean medicine practitioner can apply in the medical field. We described effects of philosophical counseling on the patient's symptom and the progress after discharge through a counseling approach based on philosophical questions. Results: During philosophical counseling, the Korean medical doctor asks questions about the nature of suffering and encourages patients to gain insight into their problems. In answering the vital philosophical questions, the patient leads to a creative interpretation of future life directions. We described the method of specific approaches through the description of the two cases. Conclusions: The philosophical counseling is compatible with the concept of Korean medicine, therefore, a Korean medicine practitioner can induce the recovery of mind and body through the creative interpretation of the patient by asking the patient the appropriate question which causes reflective thinking.

• 대한금속재료학회지
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• 제49권5호
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• pp.419-424
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• 2011

Carbon nanotubes (CNTs) were directly synthesized on a copper (Cu) plate as a current collector by the catalytic thermal vapor deposition method for an electric double-layer capacitor (EDLC) electrode. The diameters of vertically aligned CNTs grown on the Cu plate were 20~30 nm. From cyclic voltammetry (CV) results, the CNTs/Cu electrode showed high specific capacitance with typical profiles of EDLCs. Rectangularshaped CV curves suggested that the CNTs/Cu electrode could be an excellent candidate for an EDLC electrode. The specific capacitances were in a range of 25~75 F/g with a scan rate of 10~100 mV/s and KOH electrolyte concentration 1~6 M, and were maintained up to 1000 charge/discharge cycles due to strong adhesion between the Cu substrate and the CNTs.

• 한국전기전자재료학회논문지
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• 제36권2호
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• pp.175-185
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• 2023

A hybrid supercapacitor is a promising energy storage device in view of its excellent capacitive performance. Commercial three-dimensional foam nickel (Ni) can be used as an ideal framework due to an interconnected network structure. However, its application as an electrode material for supercapacitors is limited due to its low specific capacity. Herein, we report a successful growth of MnO₂ on the surface of graphene by a one-step hydrothermal method; thus, forming a three-dimensional MnO₂-graphene-Ni hybrid foam. Our results show that the mixed structure of MnO₂ with nanoflowers and nanorods grown on the graphene/Ni foam as a hybrid electrode delivers the maximum specific capacitance of 193 F·g^-1 at a current density 0.1 A·g^-1. More importantly, the hybrid electrode retains 104% of its initial capacitance after 1,000 charge-discharge cycles at 1 A·g^-1; thus, showing the potential application as a stable supercapacitor electrode.

• 대한간호학회지
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• 제11권2호
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• pp.33-54
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• 1981

The purposes of this study were to determine the relevant nursing needs of patients following discharge; to identify the degree of their nursing needs; to identify types and status of discharge order and information given to patients; and to determine their specific nursing needs according to their diagnosis. In addition, opinions toward home care services provided by hospitals or by public health nurses and appointment plans with their physicians were also asked in order to determine the necessity of follow-up care for the patient after discharge. Nine hundred and eighty eight subjects were collected among patients being discharged from one national university hospital and four city hospitals. Data were collected from June,1979 to December,1979 using questionnaires and interviews. On the bases of these data the following findings were observed; 1) Almost 40 percents of total subjects discharged from the hospital with some or great degree of nursing needs in general. The most problematic nursing needs were needs for comfort which include needs for releaving pain, for sound sleep and rest, because these needs can only be met by professional help. More than 50% of total subjects have this problem. 2) Needs for mental health, general metabolism, general hygiene and activities and safety were observed in more than 20 percent of subjects. 3) Discharge orders on diet and oral medication were recorded in patients' charts in 70% of all cases. However, more than fifty percents of patients have not been told these information from doctors or nurses. Even though some of them might have had appointment plans with their physicians, they would not keep the appointments unless they completely understood the necessity of the follow-up care. If they have not had any appointment or would not visit the out-patient clinic, there is no method of caring them and prerenting funther discomfort or complications. Even in injection, ski care, dressing and bath, only one thirds of the subjects having recorded discharge orders understood what they need after discharge. The rest of cases have not known what to do for their further care. 4) More than 80 percents and 70 percents of total subjects agreed to a system of home care services provided by hospitals or public health nurses respectively. That is, regardless of sources of medical expenses, most of patients wanted to be taken care of at home following discharge. 5) While more than half of the patients having benefit of medical insurance or paying fully by themselves had appointment plans with their physicians, only one thirds of the patients fully or partially paid by government had appointment plans with their physicians. These results ex-plain that the appointment plan is directly associated with their economic power. This indicates that the home care services are more needed to the people with lower economical status. 6) Those who have been in the hospital more than 24 days wanted !o have home care services more than those who had less hospital days. They also had more appointment plans than other groups. 7) More than 70 percents of the subjects who had been in a university hospital and approximately 30 percents of the subjects in the city hospitals had appointment plans with their physicians. 8) Those who had the cerebrovascular disease, cancer or hypertension demanded more nursing needs such as needs for comfort, for general metabolism and for mental health. 9) Factors which were associated with the degree of patients' nursing needs were age, duration of hospitalization, opinion toward home care services given by public health nurses, hospital appointments and types of hospital. That is, the older they were and the longer the periods of hospitalization were, the higher were their nursing needs. The more they had nursing needs, the more they wanted to have nursing services and had appointment plans. It can be concluded that there is a great demand for a positive and systematic home care services to the people who have been discharged from hospitals following critical care. This program is definitely demanded for the low income groups of people with less education with the financial assistance of the government or other funding agencies.

• 공업화학
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• 제24권4호
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• pp.433-437
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• 2013

다공질 세라믹 막을 사용하는 플라즈마-촉매 반응기에서 휘발성유기화합물의 분해가 수행되었다. 저압차 촉매 지지체로 사용된 세라믹 막에 광촉매인 산화아연을 담지하여 휘발성유기화합물의 산화 성능을 개선하고자 하였다. 교류 고전압에 의해 구동되는 플라즈마가 다공질 세라믹 막 내에서 전개되면서 휘발성유기화합물의 분해에 이용되는 라디칼, 오존, 이온, 여기상태 분자 등 다양한 활성성분을 생성하게 된다. 반응기에 공급되는 고전압이 증가함에 따라 플라즈마가 점차 방사방향으로 전개되어, 일정 전압을 넘어서면 세라믹지지체 전체적으로 균일한 플라즈마가 생성되었다. 휘발성유기화합물 분해 성능 평가에는 에틸렌이 이용되었다. 전기에너지밀도, 반응기 입구 에틸렌 농도, 촉매 담지 여부, 기체 조성에 따른 에틸렌 분해효율이 조사되었다. 같은 에너지 밀도에서 비교하면 산화아연이 담지된 촉매에서의 에틸렌 분해 효율이 담지되지 않은 경우보다 더 높은 것으로 나타났으며, 기체 조성 변화 실험을 통해 폐가스의 주요 구성성분인 산소와 질소 모두 에틸렌의 분해를 개시하는데 중요한 역할을 함을 알 수 있었다. 일반적인 기상반응과 달리, 플라즈마 반응기에서의 에틸렌 분해 반응은 활성 성분의 양에 의해 지배되므로, 방전 전력이 동일할 경우 에틸렌 농도가 높아질수록 분해효율이 저하되었다.

• 전기화학회지
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• 제11권1호
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• pp.47-50
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• 2008

현재 상용화 되어있는 흑연의 저용량 문제를 해결하기 위해 실리콘이나 주석계 등 고용량 비탄소계 음극전극재료들이 연구되고 있다. 이 중 산화실리콘(SiO)은 초기 충전(환원)과정에서 Li이 삽입되면서 $Li_2O$생성으로 비가역 비용량이 발생하여 초기 싸이클에서 쿨롱효율이 낮고, 싸이클링에 따라 리튬 탈 삽입 과정의 비용량이 증가하는 특징으로 실제의 전지를 설계할 시 문제점을 가진다. 본 연구에서는 고용랑 특성을 나타내는 비탄소계 실리콘을 포함하는 리튬이차전지용 음극활물질과 흑연의 복합체를 제조하여 흑연으로 실리콘의 부피팽창을 완화시키고, 사이클 특성을 향상시키는 실리콘(SiO-Graphite) 재료를 개발하고, 산화실리콘과 흑연 복합체의 높은 비가역 용량의 해소와 싸이클에 따른 리튬 탈삽입 과정의 용량증가를 해소하기 위한 전처리를 통하여 초기 효율을 향상한 전극의 제조에 대하여 연구하였다.

• 공업화학
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• 제10권8호
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• pp.1192-1199
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• 1999

Ni/Cd 전지의 페이스트식 카드뮴전극에 있어서 방전시 생성되는 $Cd(OH)_2$의 구조를 전해액에 의하여${\gamma}-Cd(OH)_2$의 구조로 변화시켜 전극에 활물질을 고밀도로 충전시키므로써 전극의 특성을 향상시켰다. 전해액은 KOH 수용액에 NaOH를 농도별로 첨가하여 사용하였다. NaOH를 1.82 M 첨가한 전해액 내에서 충 방전한 전극의 활물질 이용률이 가장 높았으며, NaOH 첨가량의 증가에 의해 방전생성물인 $Cd(OH)_2$는 ${\beta}$상에서 ${\gamma}$상으로 변화하는 정도가 증가하였다. 방전시 NaOH가 참가된 전해액에서 생성된 ${\gamma}-Cd(OH)_2$구조의 활물질 비표면적은 NaOH가 첨가되지 않은 전해액에서 생성된 ${\beta}-Cd(OH)_2$ 구조의 활물질 비표면적에 비하여 170% 이상 증가하였다. 밀폐형 전지에서는 NaOH가 첨가된 전해액의 전지가 첨가되지 않은 전지에 비하여 1.0 C와 2.0 C rate의 고율 충 방전 조건에서 방전용량이 증가하였으며, 1.0 C rate의 cycle에서도 향상된 성능이 500 cycle까지 지속되었다.