• Carbon letters
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• 제8권4호
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• pp.280-284
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• 2007

Samples of active carbon of $1150\;m^2/g$ surface area were impregnated with ammoniacal salts of copper, chromium and silver, with and without triethylenediamine. The samples of impregnated carbon were aged at $50^{\circ}C$, with and without 90% RH (relative humidity), for a little more than one year and chemically evaluated periodically. Initially copper (II) and chromium (VI) reduced very fast in the samples in humid atmosphere to the extent of 30% and 60% respectively in four months. These values were found to be unaffected by the presence of triethylenediamine (TEDA) indicating that the chemical did not retard the reduction process of chromium (VI) and copper (II). However, in the absence of humidity the reduction of the impregnants was significantly less (10-12%, w/w) in four months. It was quite evident; therefore, that the moisture was mainly responsible for the reduction of chromium (VI) and copper (II) species in impregnated carbons. The prolonged ageing of the samples with and without triethylenediamme after four months with and without humid atmosphere showed that the extent of reduction of chromium (VI) was very low, i.e. 5-10% and of copper (II) was 2-25%. Silver is not reduced due to carbon, as it remained unchanged in concentration on storage. The impregnated carbon samples (100 g) without triethylenediamine, which were aged at room temperature for 5 years in absence of humidity and unaged when evaluated against cyanogen chloride (CNCl) at a concentration of 4 mg/L and airflow rate of 30 lpm showed a high degree of protection (80- 110 minutes).

• Korean Chemical Engineering Research
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• 제47권1호
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• pp.105-110
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• 2009

Indium zinc oxide($In_2O_3-ZnO$, IZO) 박막이 poly(ethylene terephthalate) 플렉시블 기판위에 rf 마그네트론 스퍼터링을 이용하여 $Ar/O_2$ 혼합 가스하에서 rf power, 공정압력 및 IZO 두께를 변화하여 증착되었다. 공정압력이 증가됨에 따라서 증착속도는 약간씩 증가되었고 투과도에는 거의 변화가 없었으나 저항도는 증가되었다. rf power의 증가에 대하여는 증착속도가 크게 증가하였고 투과도는 미소한 변화를 보였으며 저항도는 최저점을 보인 후에 증가하였다. 가장 낮은 저항을 보인 1 mTorr와 90 W의 공정조건에서 IZO 박막의 두께변화를 실시하여 최적의 두께를 찾고자 하였다. $1,500{\AA}$ 두께의 IZO 박막이 가장 낮은 저항도를 나타냈고 염료의 최대흡수 파장영역 주변에서 높은 투과도를 보였다. 두께가 다른 투명전극들을 이용하여 제조된 태양전지의 에너지 변환효율을 측정한 결과, $1,500{\AA}$ 두께의 IZO 전극을 사용한 셀에서 2.88%의 최대 변환효율을 보였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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• pp.1060-1062
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• 1999

Pulsed Nd:YAG laser is used widely for materials processing and instrumentation. It is very important to control the laser energy density in materials processing by a pulsed Nd:YAG laser. A pulse repetition rate and a pulse width are regarded as the most dominant factors to control the energy density of laser beam. In this study, the alternating charge-discharge system was designed to adjust a pulse repetition rate. And the parallel mesh is added to increase laser output power. This system is controlled by one chip microprocessor and allows to replace an expensive condenser for high frequency to a cheap condenser for low frequency. In addition, we have investigated the current pulse shape of flashlamp and the operating characteristics of a pulsed Nd:YAG laser. As a result, it is found that the laser output of the power supply using the parallel mesh and the alternating charge-discharge system is not less than that of typical power supply. As the pulse repetition rate rises from 10pps to 110pps by the step of 20pps at 1000V and 1200V, it is found that the laser efficiency decreases but the laser output power increases about 5W at each step.

• 센서학회지
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• 제7권2호
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• pp.103-110
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• 1998

강유전체 박막과 마이크로 가공기술을 이용하여 초전형 적외선 센서를 제작하였다. 초전형 적외선 센서는 $Pb_{l-x}La_{x}Ti_{1-x/4}O_{3}$ (x=0.05) (PLT) 강유전체 박막 커패시터를 RF 마그네트론 스퍼터링 방식으로 백감 전극이 증착된 MgO 기판상에 결정 성장시킨 구조를 갖고 있다. 스퍼터링된 PLT 박막은 높은 c-축 결정 구조를 가지므로 센서로 사용하기 위한 분극 처리 과정이 필요 없다. 이는 적외선 이미지 센서를 구현함에 있어서 수율 향상에 필수적인 요소이다. 또한 마이크로 가공 기술을 사용하여 센서의 열용량을 극소화함으로서 센서의 효율을 최대화하였다. 제작된 센서의 상부에 폴리이미드를 코팅하고 MgO 기판을 선택적으로 식각하여 코팅된 폴리이미드와 MgO가 강유전체 박막 커패시터를 지지하고 있는 구조를 구현하였다. 이렇게 제작된 센서의 감도는 상온에서 $8.5{\times}10^{8}cm{\cdot}\sqrt{Hz}/W$로 측정되었으며 이는 마이크로 가공 기술을 사용하지 않은 경우보다 약 100 배의 감도 향상을 가져왔다. 2차원 배열 구조를 갖는 센서를 가지고 인체의 유 무 뿐만 아니라 위치까지 감별할 수 있는 센싱 시스템을 구현하였다.

• 지구물리와물리탐사
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• 제1권2호
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• pp.110-115
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• 1998

전도성 황화광체의 탐사에는 현장작업의 편이성과 저렴한 조사 경비 및 성과의 신뢰성으로 자연전위탐사, VLF 전자탐사 및 전기비저항 쌍극자탐사법이 많이 사용되어 왔다. 금번 탐사는 전라북도 진안군 부귀면에 소재 하는 장금 광산의 맥상의 노두 광체를 대상으로 맥상 황화광체에 대한 물리탐사 탐사 반응을 검토하고 이를 시추탐사 결과와 대비, 고찰하여 보았다. 조사지역 부근의 지질은 유천층군의 퇴적 암류와 산성 화산암류로 구성되며 광상은 광염상 또는 맥상으로 황철석, 자류철석 및 방연석 등의 황화광물이 배태된다. 이들 맥상 광체에 의한 전형적인 이상대가 각각 포착되었는데, 자연전위탐사 결과 광체는 등전위선 분포가 조밀하고 전위 경도가 큰 쪽으로 경사지며, VLF 전자탐사 결과 광체의 부존 범위와 잘 일치되며 서쪽으로 경사지는 광체에 의한 반응임이 확인되었다. 쌍극자 전기비저항탐사 결과 역시 서쪽으로 경사지는 광체에 의한 반응이 확인되었다. 이에 대한 시추탐사 결과 광체는 주향 방향으로 약 50 m 연장되며 약 $70^{\circ}W$경사를 가진 맥상 광체임이 밝혀졌다.

• Plant Resources
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• 제3권2호
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• pp.110-117
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• 2000

The recycling method of enokitake cultural waste and the potentiality of second flush for enokitake were determined, because this fungus is not as prolific as the more commonly cultivated white rot fungi in the conversion of sawdust to mycelial mass. The mycelial growth of F. velutipes on several substrates, variously treated with rice bran was promoted at ratios of 10-20% (w/w) on all substrates, but suppressed at above ratios, although some difference was there. The mycelial densities generally increased correlated to the supplementation contents of rice bran. It could be concluded that F. velutipes preferred mild acidic to acidic conditions for mycelial growth, considering that the mycelial growth rate was highest on waste of pH 6.01, treated with 0.1 % Ca(OH)$_2$ and on populus mixed waste of pH 6.02, non treated. The ranges of substrate bulk densities, which was pertinent for mycelial linear growth were from B.D. (g/cc) 0.17 to 0.23 on waste and populus mixed waste all. The pertinent contents of rice bran supplementation in bottle cultivation was from 20 to 30% on waste and 20% on populus mixed waste, considering the requried duration for pinheading and fruiting yields. Standard bulk density for filling and utilizing the waste and populus mixed waste for commercial f. velutipes cultivation were B.D.(g/cc) 0.19 ~ 0.23, and 0.23~ 0.25, which could be conversed to 510~ 540g/900m1 and 520~ 570g/900m1, respectively, The second flush of F. velutipes was tried and the re-inoculation by sawdust and liquid spawn showed somewhat good results, indicating the potentiality of second crop and suggesting further research for it.

• Nuclear Engineering and Technology
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• 제48권1호
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• pp.164-168
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• 2016

Lean duplex stainless steels with 0.087 wt.% gadolinium (Gd) were inert arc-melted and cast in molds of size $10mm{\times}10mm{\times}20mm$. The micro-hardnesses of the rolling direction (RD), transverse direction (TD) and short transverse (ST) direction were $258.5H_V$, $292.3H_V$, and $314.7H_V$, respectively. A 33% cold rolled specimen had the crystallographic texture that (100) pole was mainly concentrated to the normal direction (ND) and (110) pole was concentrated in the center of ND and RD. The corrosion potential and corrosion rate in artificial seawater and $0.1M\;H_2SO_4$ solution were in the range of $105.6-221.6mV_{SHE}$, $0.59-1.06mA/cm^2$, and $4.75-8.25mV_{SHE}$, $0.69-1.68mA/cm^2$, respectively. The friction coefficient and wear loss of the 0.087 w/o Gd-lean duplex stainless steels in artificial seawater were about 67% and 65% lower than in air, whereas the wear efficiency was 22% higher. The corrosion and wear behaviors of the 0.087 w/o Gd-lean duplex stainless steels significantly depended on the Gd phases.

• 한국통신학회논문지
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• 제40권1호
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• pp.9-15
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• 2015

S급 전력 증폭기 응용을 위한 CMOS 대역 통과 델타 시그마 변조기(BPDSM)와 캐스코드 E급 전력 증폭기를 설계 및 제작 하였다. 대역 통과 델타 시그마 변조기는 1 GHz의 샘플링 주파수로 250 MHz의 입력 신호를 펄스폭 변조 방식의 디지털 신호로 변조하며 양자화 잡음을 효과적으로 제거하였다. 대역 통과 델타 시그마 변조기는 25 dB의 SQNR을 가지며 1.2 V 전원 전압에서 24 mW의 전력을 소비한다. 캐스코드 E급 전력 3.3V 전원에서 동작하며 최대 18.1 dBm의 출력 전력을 가지며 25%의 드레인 효율을 보였다. 두 회로 모두 동부 0.11 um RF CMOS 공정으로 제작되었다.

• Applied Biological Chemistry
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• 제26권2호
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• pp.110-118
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• 1983

병(病)든 콩의 줄기와 뿌리에서 분리(分離)한 bacteria균주(菌株) SAF-C는 운동성(運動性)이 있으며 동정(同定)한 결과(結果) Agrobacterium radiobacter임이 밝혀졌다 또 anilineblue 방법(方法)으로 이 균주중(菌株中) 수용성(水溶性) 다당(多糖)만을 거의 완전(完全)하게 생산(生産)하는 균주(菌株)를 선별(選別)하고 SAF-C.W라 하였다. 진탕배양에서 SAF-C.W의 높은 산성(酸性), 수용성다당(水溶性多糖)의 생산조건(生産條件)을 찾기 위하여 본 실험(實驗)이 행(行)하여졌다. 많은 양(量)의 다당(多糖)이 glucose 4%, $CaCO_3$ 0.3% 질소원(窒素源)으로 yeast extract, $(NH_4)_2HPO_4$ 및 distillers dried solubles(D.DS.)을 0.5% 포함(包含)하는 각각의 배지(培地)에서 생산(生産)되었으며, 그 생산율(生産率)은 22.9%, 10%, 9.6%이었다. 또 glucose 3%, D.D.S. 0.4% $K_2HPO_4$ 0.5%, $MgSO_4{\cdot}7H_2O$ 0.01%의 조성(組成)을 가지는 배지(培地)에서 다당수득율(多糖收得率) 25%를 기록(記錄)하였다.

• 패션비즈니스
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• 제12권5호
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• pp.94-110
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• 2008

The main objective of this research was to understand the characteristics of separation color coordination of contemporary female fashion through the analysis of 'pre-a-porter Collections' of four collections (i. e. cities) - Paris, Milan, New York, London - from the periods of 2004 S/S to 2008/9 A/W. The data collection of 265 was done by reviewing 'pre-a-porter Collections' magazine and total 265 observations were made. Statistical analysis of frequency and also qualitative interpretation of separation color coordination characteristics were completed. The main findings were; (1) In separation color coordination of contemporary women's fashion collections, there were three main types of color scheme which were classified into seven detailed categories of color combination. First was the achromatic color & one chromatic separation color scheme which was classified into four categories of - black & white, black & grey, white & grey, and grey & grey - color combination. Second was the chromatic colors & one achromatic separation color scheme which classified into two categories of achromatic & chromatic color & one achromatic separation color combination, and chromatic colors & one achromatic separation color combination. Third was chromatic colors and one chromatic separation color combination. (2) The achromatic colors and one chromatic separation color scheme showed two phases of reinforcing the strong and modern image, or softening the hard and dull image of achromatic color combination. In color schemes which used more than two chromatic colors, the separation color frequently converted the tedious and monotonous fashion image, which caused by identical or similarity in color or tone harmony, into more attractive and interesting. (3) In conclusion, through the various use and coordination of various color schemes, color harmony and separation colors, the separation color coordination in contemporary female fashion has been suggested the effective way of color combination which can lead the visual pleasure and the vitality along with the unity and the harmony. This characteristics can create various images and visual diversity for fashion. The types and the use of color scheme and separation color showed different trends in four collections.