液體膜에 의한 Cyclohexane과 n-Heptane 混合物의 分離에 있어서 界面活性劑가 미치는 影響

崔洙鉉,鄭泰秀 成均館大學校 科學技術硏究所 1994 論文集 Vol.45 No.2

In the separation of cyclohexane-n-heptane mixture by liquid membrane in a batch system, the effects of surfactants on the separation factor were investigated with the surfactant concentration ranging from 0.2 to 1.0wt%. The surfactants used were sodium lauryl sulfate, sodium laurylether sulfate and triethanolamine lauryl sulfate. The separation was most effective at the surfactant concentration of 0.4wt% and at the emulsification speed of 1200 rpm for all three surfactants. The separation was also most effective at the contact time of 20 mimutes for sodiurn lauryl sulfate and 15 minutes for sodium laurylether sulfate at the settling time of 10 minutes, while it was so for triethanolamine lauryl sulfate at the contact time of 20 minutes and the settling time of 15 minutes.

DLTS에 의한 열처리시킨 HB-GaAs에서의 깊은준위

崔玄泰,金仁洙,孫貞植,裵仁鎬,金相基 嶺南大學校 基礎科學硏究所 1993 基礎科學硏究 Vol.13 No.-

Deep levels in horizontal Bridgman(HB) undoped GaAs were investigated by DLTS system personally manufactured. In as grown sample, three electron traps of which activation energies are T1(E?-0.32eV), T2(E?-0.54eV) and T3(E?-0.82eV) were observed. As sample was annealed at 650℃, T3 level was separated into T3?(E?-0.74eV) and T3 level. When sample was annealed at 800℃, only T3* level was observed. For sample annealed at 900℃, T3* and T3 level were observed. From these results, EL2's origin is very complicated complex and explanation is very difficult, but the model of As??-V??-A??-V?? is enough to explain the EL2's behavior of annealing temperature.

一部 男子大學生들과 運動選手들의 一側優位性(左右差:手·足·體·眼)에 關한 比較硏究

백현중,윤태영,최중명,박순영 慶熙大學校 1991 論文集 Vol.20 No.-

This study is from March 1st, of 1988 to September 31, 1988. The subjects of study consists of students in general who are in attendance at university and all samples are selected at random. The total number of subjects counts to 187(sports man : 56, College students : 131) and the researcher measures and analyses the subjects' physique, physical strength, the test of dominance eye, the functional tests of hand, foot, body and eye. The results as follows : 1. Physical growth and development Mean values of body height are 177.19±5.01㎝ for sports man and 173.3±0.46㎝ for college student and superior to standard value of Korean. Mean values of body weight are 69.6.±6.17㎏ for sports man and 66.1±1.68㎏ for college student, and the mean values of chest girth are 91.86±4.83㎝ and 94.1±1.53㎝. Mean values of sitting height are 93.0±4.28㎝ and 93.3±1.05㎝. 2. Physical fitness Mean values of grin strength are 41.6±4.3 for right side and 44.0±6.0 for left side in sports man and 44.2±1.4 for right and 46.3±1.7 for left in college student. Mean values of arm strength are 29.7±3.9 for right and 31.8±2.9 for left in sports man 25.±1.4 or right and 28.7±1.9 for left in college student. Mean values of leg strength are 38.4±5.8 for right and 43.8±6.1 for left in sports man and 43.5±1.8 for right and 44.2±1.1 for left in college student. 3. Functional rate of foot, trunk, eye and hand As considered according to its functions, the rates of right foot, left foot, both of feet in both of the sports man and college student, total rates are each of 83.3%, 16.7%, 2.4% for sports man and 53.7%, 39.0%, 2.6% for college student. The rates of right side, left side, both of sides in both of the sports man and college student, the total rates are each of 53.3%, 37.4%, 6.7% for sports man and 39.1%, 46.1%, 5.1% for college student. The rates of right eye, left eye, both of eyes in both of the sports man and college student, the total rates are each of 53.6%, 31.7%, 4.1% for sports man and 53.3%, 20.8%, 22.7% for college student. The rates of right hand, left hand, both of hands in both of the sports man and college student, the total rates are each of 67.5%, 21.8%, 5.2% for sports man and 84.5%, 10.4%, 2.2% for college student, respectively. 4. Tests of dominance eye As considered according to tests of dominance eye, the results of right eye, left eye in both sports man and college student, results are each of 62.5%, 37.5% for sports man and 70.2%, 29.8% for college students, 67.9%, 32.1% for the total of sports man and college student, respectively.

이온주입이 금속의 일함수에 미치는 영향(Ⅰ)

김현경,강석태,황정남,이철주,최대선,정병두 연세대학교 자연과학연구소 1984 學術論文集 Vol.13 No.-

이온 주입이 일함수 차이에 미치는 영향을 연구하기 위하여 낮은 에너지 이온 가속기, 전자총과 기타 일함수 차이를 측정하기 위한 장치를 설계, 제작하였다. 제작된 이온 가속기의 집속 특성은 이론적인 값과 일치하였다. 즉, 집속 렌즈의 확대율이 이론값은 2.0인데 비하여 1.2로 상당히 작은 값이었다. 또한 집속 렌즈의 전압 V_L과 추출 전압 V_e에 의한 집속 특성 역시 이론값과 매우 잘 일치하였다 . 제작된 장치를 사용하여 다결정 Cu와 Ni의 일함수 차이를 측정한 결과 0.45eV임을 알았다. 그리고 전자선을 이용하여 억제 전위차로 일함수를 측정할때 입사 전자의 반사율을 고려해야 함을 알았다. Low energy ion accelerator, electron gun, and apparatus for measuring work function difference are designed and constructed in order to study the effect of ion implantation on the work function. The focusing properties of accelerator is coincided with theoretical results; the magnification of Einzel lens is found to be 1.2, while theoretical value is 2.0, and the focal properties as a function of V_L/V_e are in good agreement with theory. Using these systems, the work function difference between polycrystalline Cu and Ni is found to be 0.45eV, and the experimental retarding potential plots indicate close agreement with the theoretical values modified by electron reflection.

평판의 진동에 따른 음향방사MODE에 관한 연구

김예현,최현태,장호경 嶺南大學校 基礎科學硏究所 1991 基礎科學硏究 Vol.11 No.-

In structure, Efficiency of structure itself and operation efficiency are reduced by the noise radiated from vibration. In this paper, The vibration of plate and its sound radiation are studied. The measured value of odd mode is not corresponded to the theoratical value because its nodal lines pass through the excitation point. But, the measured value of even mode is corresponded to theoratical value. When the plate was excited by frenquency with two modes, the very complexed sound-radiation-mode was observed due to the coupling effect of two modes.

우관상동맥 개구부 완전 폐쇄가 동반된 대동맥 판상부 협착증 1례

임상현,김종진,김희열,진승원,전희경,노태호,채장성,김재형,홍순조,최규보,윤정섭,김치경 대한순환기학회 2000 Korean Circulation Journal Vol.30 No.4

나리屬 식물의 촉성 재배에 있어 엽초 제거가 생육에 미치는 영향

정우윤,최상태,박인환,김성태,박현근 慶北大學校 農業科學技術硏究所 2003 慶北大農學誌 Vol.21 No.-

The study aimed to identify leaf sheath through the investigation a characteristic of leaf by planting depth and leaf sheath function through the investigation of effect of leaf sheath removals on growth and flowering in forcing of Lilium cultivars. The number of leaf sheath of 'Jolanda', 'Dream Land', 'Casablanca' were 6, 5, 11 in 0㎝ planting depth and 6, 5, 14 in 6㎝ planting depth. The number of leaf sheath in 'Jolanda' and 'Dream Land' were little different in according to planting depth. The other hand, the number of leaf sheath in 'Casablanca' were increased 3 when it were planted in 6㎝ planting depth. As leaf sheath were removed, plant height and stem root growth were decreased in 'Le Reve' and 'Casablanca'. Whereas the growth of basal root and flower number varied among of Lillium and stem diameter, the days of flowering and flower size were little different.

DLTS에 의한 LPE GaAs 및 Al0.32Ga0.68As의 깊은준위 조사

金仁洙,崔玄泰,李哲旭,裵仁鎬,金末文 嶺南大學校 基礎科學硏究所 1993 基礎科學硏究 Vol.13 No.-

Deep levels in liquid phase epitaxy(LPE) GaAs and Al??Ga??As were investigated by deep level transient spectroscopy(DLTS) method. In LPE n-GaAs, The main electron trap observed was the T1(EL2) at Ec-0.82eV. For Al???Ga???As, two electron traps T2(Ec-0.32eV) and T3(Ec-0.82eV) were observed. The origins of EL2(Tl or T3) and DX center(T2) are As??-V?? complex and donor complex related impurity, respectively. After annealing at 795℃, the peak at low temperature decreased but peak at high temperature had broad shape and increased. The level observed at high temperature is EL2 family.

저열량영양식품 섭취에 따른 비만여성의 체중감량 효과에 관한 연구

박순영,최중명,김동현,최경식,최봉근,윤태영,유동준 한국보건통계학회 2002 보건정보통계학회지 Vol.27 No.1

In the method of obesity treatment, Dietary method, Exercise method, Behavior method, and Drug method, Dietary method is the most important control method of obesity. The aim of this study is that evaluate the weight reduction effect of the specific low calorie diet products (KSD I and 2) in obese women. Twenty five women who were volunteer participated in this study. They have no heart diseases and metabolic diseases. we classified two groups : obese group and standard group. Anthropometric indices were measured in all subject for four times. Venous blood sample were taken to determine the lipid profiles, glucose level, and liver function test. In obese group, body weight were reduced 2.85±1.46kg, but showed statistically non-signicicant. Body mass index were gradually reduced, 1.09±0.93kg/m^2(p<0.05).In blood analyses, total cholesterol were reduced 10.61 ±33.4mg/dℓ ( p<0.05). KSD 2 significantly inhibited maltase, sucrase and α-glucosidase from rat intestine, and porcine pancreatic lipase, although KSD I inhibited only the sucrase.

턴디슈용 SiC 코팅材의 특성에 관한 硏究

김행식,최태현,이용구,전병세 경남대학교 신소재연구소 1995 論文集 Vol.5 No.-

턴디쉬 내장용으로 사용할 내화재료의 여러 가지 특성들을 시험하였다. 납석 70%, 점토 10% 그리고 탄화규소 20%을 혼합하여 18 가지의 조성을 가지는 시험편을 제조하였다. 탄화규소는 각각 순도 85%와 65%인 유럽산, 일본산, 중국산을 택하여 최종 제품에 미치는 영향을 알아보았다. 여러 가지 시험의 결과 10% 탄화규소를 포함한 시험편의 경우 점토질 내화벽돌 보다 수명이 2배 정도 향상되었으며 차지당 용손 두께도 1.5∼1.7㎜/ch였다. Various properties of refractory materials for the tundish lining were examined. The refractory samples with 18 different composition were prepared by mixing powders of 70 wt.% pyrophyllite. 10 wt.% clay and 20 wt.% Sic. SiC was selected from three sources, European. Japanese and Chinese-made, having 85% and 65% purities, to examine their effects on the final properties. As a results of several testings. the sample with 10% SiC(European1 was best suitable for tundish lining as a refractory coating materials. The wear depth was 1.2-1.5 mm per charge at the wall and 1.7 mm per charge a t the slag line, having shown that this service life was about 2 times longer than the ordinary lining made of clay firebricks(SiO₂-Al₂O₃).