• 한국결정성장학회지
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• 제18권5호
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• pp.217-224
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• 2008

수평 전기로에서 $ZnIn_2Se_4$ 단결정을 합성하여 HWE(Hot Wall Epitaxy)방법으로 $ZnIn_2Se_4$ 단결정 박막을 반절연성 GaAs(100) 기판에 성장시켰다. $ZnIn_2Se_4$ 단결정 박막의 성장 조건을 증발원의 온도 $630^{\circ}C$, 기판의 온도 $400^{\circ}C$였고 성장 속도는 0.5 $\mu m/hr$였다. $ZnIn_2Se_4$ 단결정 박막의 결정성의 조사에서 10K에서 광발광(photoluminescence) 스펙트럼이 682.7nm ($1.816{\underline{1}}eV$)에서 exciton emission 스펙트럼이 가장 강하게 나타났으며, 또한 이중결정 X-선 요통곡선(DCRC)의 반폭치(FWHM)도 128 arcsec로 가장 작아 최적 성장 조건임을 알 수 있었다. Hall 효과는 van der Pauw 방법에 의해 측정되었으며, 온도에 의존하는 운반자 농노와 이동도는 293 K에서 각각 $9.41\times10^{16}/cm^{-3}$, $292cm^2/V{\cdot}s$였다. $ZnIn_2Se_4$/SI(Semi-Insulated) GaAs(100) 단결정 박막의 광흡수와 광전류 spectra를 293 K에서 10K까지 측정하였다. 광흡수 스펙트럼으로부터 band gap $E_g(T)$는 varshni공식에 따라 계산한 결과 $E_g(T)=1.8622\;eV-(5.23\times10^{-4}eV/K)T^2/(T+775.5K)$ 이었으며 광전류 스펙트럼으로부터 Hamilton matrix(Hopfield quasicubic mode)법으로 계산한 결과 crystal field splitting energy ${\Delta}cr$값이 182.7meV이며 spin-orbit energy ${\Delta} so$값은 42.6meV임을 확인하였다. 10 K일 때 광전류 봉우리들은 n= 1, 27일때 $A_{1}-$, $B_{1}-$와 $C_{27}-exciton$ 봉우리임을 알았다.

• 공업화학
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• 제9권6호
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• pp.870-877
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• 1998

본 연구에서는 임피던스 스펙트럼 분석법을 사용하여 중성운반체로 dibenzo-18-crown-6 (D18Cr6)와 valinomycin (Val)을 이용하여 $K^+$이온선택성 PVC막 전극의 막과 용액계면에서의 임피던스 특성을 검토하였다. PVC막에 대한 운반체의 종류와 함량, 가소제, 막두께, 기본전해질의 혼입(doping)여부 및 이온의 농도변화 등을 교류임피던스 분석법을 이용하여 측정하였고, 그 결과를 전극특성과 비교 검토하고 PVC막 전극에서의 전달특성을 규명하였다. 교류 임피던스의 특성을 측정하여 중성운반체로 D18Cr6와 Val을 포함하고 있는 PVC막 전극의 등가회로는 막의 벌크저항과 전기이중층 용량을 포함하는 기하학적용량을 병렬로 하고, 용액저항과 직렬로 구성되는 임피던스의 등가회로임을 확인할 수 있었다. 그러나 저농도 및 저주파수 영역에서 약간의 전하전이저항과 Warburg저항이 나타나 중첩되는 것을 알 수 있었다. $K^+$이온선택성 전극에서 운반체로서 D18Cr6가 Val중 D18Cr6가 기존의 Val보다 전극특성 및 임피던스 특성이 좋았으며 특히 D18Cr6에 기본전해질로 potassium tetraphenylborate (TPB)를 첨가한 경우 이상적인 전극을 제조할 수 있었다. 운반체의 최적 함량은 D18Cr6와 Val의 경우 3.23wt%부근이었고, 가소제는 DBP가 가장 적절하였다. 막두께가 얇아질수록 임피던스 특성이 좋아졌으나, 막두께가 최적 막두께 이하로 얇아지면 전극특성이 나빠짐을 알 수 있었다. D18Cr6의 경우 $K^+$이온에 대한 혼합용액법에 의한 선택계수 서열은 다음과 같았다. $NH_4{^+}>Ca^{2+}>Mg^{2+}>Na^+$.

• 센서학회지
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• 제11권5호
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• pp.309-318
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• 2002

수평 전기로에서 $CdIn_2S_4$ 다결정을 합성하여 HWE(Hot Wall Epitaxy)방법으로 $CdIn_2S_4$ 단결정 박막을 반절연성 GaAs (100)기판에 성장시켰다. $CdIn_2S_4$ 단결정 박막의 성장 조건은 증발원의 온도 $630^{\circ}C$, 기판의 온도 $420^{\circ}C$였고 성장 속도는 $0.5\;{\mu}m/hr$였다. $CdIn_2S_4$ 단결정 박막의 결정성의 조사에서 10 K에서 광발광(photoluminescence) 스펙트럼이 463.9 nm (2.6726 eV)에서 exciton emission 스펙트럼이 가장 강하게 나타났으며, 또한 이중 결정 X-선 요동 곡선(DCRC)의 반폭치(FWHM)도 127 arcsec로 가장 작아 최적 성장 조건임을 알 수 있었다. Hall 효과는 van der Pauw 방법에 의해 측정되었으며, 온도에 의존하는 운반자 농도와 이동도는 293K에서 각각 $9.01{\times}10^{16}/cm^3$, $219\;cm^2/V{\cdot}s$였다. $CdIn_2S_4$/SI(Semi-Insulated) GaAs(100) 단결정 박막의 광흡수와 광전류 spectra를 293K에서 10K까지 측정하였다. 광흡수 스펙트럼으로부터 band gap $E_g(T)$는 Varshni 공식에 따라 계산한 결과 $2.7116eV-(7.74{\times}10^{-4}eV/K)T^2$/(T+434K)이었으며 광전류 스펙트럼으로부터 Hamilton matrix(Hopfield quasicubic mode)법으로 계산한 결과 crystal field splitting ${\Delta}cr$값이 0.1291 eV이며 spin-orbit ${\Delta}so$값은 0.0248 eV임을 확인하였다. 10K일 때 광전류 봉우리들은 n = 1일때 $A_1$-, $B_1$-와 $C_1$-exciton 봉우리임을 알았다.

• Clinical and Experimental Reproductive Medicine
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• 제36권4호
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• pp.275-281
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• 2009

목 적: 본 연구는 반복적으로 체외수정시술/난자세포질내 정자주입술을 실패했던 환자에서 배아 이식시 옥시토신 길항제의 투여가 임신율 및 착상율에 미치는 영향을 알아보고자 하였다. 연구방법: 2회 이상의 체외수정시술/난자세포질내 정자주입술을 실패했던 40명의 환자들을 대상으로 전향적 무작위 연구를 진행하였다. 과배란유도 방법으로 생식샘자극호르몬분비호르몬 길항제 다회투여법이 사용되었다. 실험군에서는 옥시토신 길항제로 atosiban (vasopressin $V_{1A}$/oxytocin antagonist)을 배아 이식 한 시간 전에 atosiban 6.25 mg을 일회 정주한 뒤, 18 mg/hour의 속도로 지속적 정맥 주입하였다. 배아 이식이 끝난 뒤 atosiban을 6 mg/hour로 감속하여 2시간 동안 추가로 정맥 주입하였다. 실험군과 대조군간의 체외수정시술 결과를 비교 분석하였다. 결 과: 실험군과 대조군간의 평균 나이, 불임 기간 및 체질량 지수와 기저 혈중 난포자극호르몬 및 에스트라디올 농도, 기저 난포강 난포의 수에 통계적으로 유의한 차이는 없었다. 또한 투여된 재조합 인간 난포자극호르몬 (rhFSH)의 총 용량과 투여 기간, 발달된 난포의 개수 및 자궁내막의 두께 역시 통계학적 유의한 차이를 보이지 않았다. 수집된 난자 및 성숙 난자의 수와 수정된 난자와 1등급 혹은 2등급의 배아 및 이식된 배아의 수에도 두 군간의 통계학적으로 유의한 차이를 보이지 않았다. 착상율을 비교하였을 때 실험군은 16.9% (11/65), 대조군은 6.0% (4/67)로 나타났고, p=0.047로 두군 간에 통계학적으로 유의한 차이를 보였다. 임상적 임신율의 경우 실험군은 40.0%로 대조군의 20.0%에 비해 높게 나타나으나 통계학적 유의성엔 도달하지 못하였다. 또한 자궁외 임신 및 유산율에 있어서는 두 군 간에 유의한 차이를 보이지 않았다. 결 론: 체외수정시술/난자세포질내 정자주입술을 시행 받는 환자들에서 배아 이식 동안 옥시토신 길항제를 투여하는 것은 자궁의 수축을 감소시켜 착상율을 증가시킬 수 있을 것으로 생각된다.

• 복식
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• 제39권
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• pp.217-237
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• 1998

The present research is to study the make-up culture of Korea and its neighboring countries such as China and Japan during the period from the prehistoric age to the 19th cen-tury. The research was made by documents analysis. The results are summerised as follows : (1) A man has a basic instinct to beautify himself. There was not a significant difference between the make-up behavior of men and women in its primal stage. It was by the start of farming and the division of labor that made the make-up behavior as a feminine culture. The difference of sexual role caused the con-ceptual difference between manly beauty and womanly beauty. It was very natural for women to regard the make-up as the best way for showing their feminine beauty. In Korea, China and Japan, there were vari-ous kinds of primal actions such as tattooing, body-painting, and tooth make-up which were used in the purpose of body protection, incantation, ornament, and so on. Ass their ornamental purpose was becoming more important, these primal actions became the basis of the feminine make-up culture. Nowadays make-up, having mental and emo-tional function, is helpful to increasing self-satisfaction, promoting good personal relation-ship, and attracting attention from the other sex. It also has other functions of showing social status, wealth, age, sex, courage, power, and so on. (2) The representative make-up product used widely in the three countries was Boon (powder) which decides the overall color of face. The key point in the production of Boon was to increase its power of adsorption. The invention of Yunboon (power mixed with lead) solved this major problem of Boon. Yeonji which decides the color of cheek was the mixture of Boon and the powder of Honghwa (a kind of red-colored flower or tree). Mimook (eyebrow pencil) was developed to match up with the various and changing currencies of penciling eyebrows in each nation and times, Yeonji and Joosa (red sand) were used as Jinji (lip stick). The predominant color of Jinji was red. As miscellaneous methods of partial make-up, there were Kon-ji used in a wedding cer-emony in korea, Aek-hwang, Hwa-jeon, Sa-hong, and Myun-yup in China, and Chi-heuk, a peculial method of partial make-up in japan. (3) There were various factors which decided the characteristics of make-up culture usually reflects international atmosphere, the form of government, economic situation, re-ligious and social ideology, aesthetic sense, symbolizing meanings of colors, and so on. The up and down of an influentian country was one of the major factors which decided the characteristics of the make-up culture of its neighboring countries. When a country took a liberal form of government, it had diverse and splendid tendencies in its make-up culture. The better a nation's economic situation is, the more abandant and various its make-up culture is, and sometimes, the more eccentric and decadents it was. In the field of make-up production, the three countries had their own characteristics. But, as a whole, China was the leading nation who spread the culture and products of make-up to Korea and Japan. Though the Chinese make-up culture and products were usually spread to Japan through Korean, there was some evidence of direct exchanges between China and Japan through its dispatches of Kyun-Tang-Sa(Japanese delegation to the Tang Dynasty). While religion had a positive influence on the development of make-up culture by introducing new methods of make-up, Confucianism exercised strict control over the make-up cul-ture. The currencies in arts and changes of esthetic sense introduced new methods and booms to the make-up culture. Literature made people pay increasing attentions to the countenances of women and changed the standards of esthetic sense. We can find out that the social status of woman was also reflected in the make-up culture. As the social status of women became higher, the feminine make-up culture also developed more then ever. As mentioned above, the make-up cultures of the three countries reflected their social values, esthetic senses, and emotional feelings. Through their cultural exchanges, the three countries could develop various make-up products and methods.

• 한국결정성장학회지
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• 제21권3호
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• pp.99-104
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• 2011

단결정 성장을 위한 $MgGa_2Se_4$ 다결정은 수평 전기로에서 합성하였으며, 결정구조는 rhombohedral이고 격자상수 $a_0$는 3.953 ${\AA}$, $c_0$는 38.890 ${\AA}$였다. $MgGa_2Se_4$ 단결정박막은 HWE(Hot Wall Epitaxy) 방법으로 반절연성 GaAs(100)기판에 성장시켰다. 단결정박막의 성장 조건은 증발원의 온도 $610^{\circ}C$, 기판의 온도 $400^{\circ}C$에서 진행되었으며 성장 속도는 0.5 ${\mu}m/h$였다. 단결정박막의 결정성은 이중 결정 x-선 회절곡선의 반폭치와 X-선 회절무늬의 ${\omega}-2{\theta}$로부터 구하여 최적 성장 조건을 알 수 있었다. Hall 효과는 van der Pauw 방법에 의해 측정되었으며, 온도에 의존하는 운반자 농도와 이동도는 293 K에서 각각 $6.21{\times}10^{18}/cm^3$, 248 $cm^2/v{\cdot}s$였다. $MgGa_2Se_4$/SI(Semi-Insulated) GaAs(100) 단결정 박막의 광흡수 스펙트럼을 10 K에서 293 K까지 측정하였다. 광흡수 스펙트럼으로부터 구한 에너지 갭 $E_g(T)$는 varshni 공식 $E_g(T)=E_g(0)=({\alpha}T^2/T+{\beta})$을 잘 만족함을 알 수 있었다. 여기서 $E_g(0)=2.34\;eV$, ${\alpha}=8.81{\times}10^{-4}\;eV/K$, ${\beta}=251\;K$였다.

• IMMUNE NETWORK
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• 제3권1호
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• pp.1-7
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• 2003

Type II collagen (CII), major component of hyaline cartilage, has been considered as an auto-antigen in rheumatoid arthritis (RA). However, the clinical and biological significances with regard to the CII autoimmunity need to be clarified in human RA. The presence of antibodies to CII has been identified in sera, synovial fluid, and cartilage of patients with RA. In our study, the increased titer of IgG anti-CII in sera was well correlated with C-reactive protein, suggesting that this antibody may reflect the inflammatory status of RA. The titer of anti-CII antibodies (anti-CII Abs) tended to be higher in early stages of diseases. In our extending study, among 997 patients with RA, 269 (27.0%) were positive for circulatory IgG antibody to CII, those levels were fluctuated over time. It is hard to assess the significant amount of T cell responses to CII and CII (255~274) in RA. By using a sensitive method of antigen specific mixed lymphocyte culture, we can detect the presence of CII-reactive T cells in peripheral blood mononuclear cells of RA patients. Sixty seven (46.9%) of 143 patients showed positive CII reactive T cell responses to CII or CII (255~274). The frequencies of CII reactive T cells were more prominent in inflamed synovial fluid (SF) than in peripheral blood. These T cells could be clonally expanded after consecutive stimulation of CII with feeding of autologous irradiated antigen presenting cells (APC). Moreover, the production of Th1-related cytokine, such as IFN-${\gamma}$, was strongly up-regulated by CII reactive T cells. These data suggest that T cells responding to CII, which are probably presenting the IFN-${\gamma}$ producing cells, may play an important role in the perpetuation of inflammatory process in RA. To evaluate the effector function of CII reactive T cells, we investigated the effect of CII reactive T cells and fibroblasts-like synoviocytes (FLS) interaction on the production of pro-inflammatory cytokines. When the CII reactive T cells were co-cultured with FLS, the production of IL-15 and TNF-${\alpha}$ from FLS were significantly increased (2 to 3 fold increase) and this increase was clearly presented in accord to the expansion of CII reactive T cells. In addition, the production of IFN-${\gamma}$ and IL-17, T cell derived cytokines, were also increased by the co-incubation of CII reactive T cells with FLS. We also examined the impact of CII reactive T cells on chemokines production. When FLS were co-cultured with CII stimulated T cells, the production of IL-8, MCP-1, and MIP-1${\alpha}$ were significantly enhanced. The increased production of these chemokines was strongly correlated with increase the frequency of CII reactive T cells. Conclusively, immune response to CII was frequently found in RA. Activated T cells in response to CII contributed to increase the production of proinflammatory cytokines and chemokines, which were critical for inflammatory responses in RA. The interaction of CII-reactive T cells with FLS further augmented this phenomenon. Taken together, our recent studies have suggested that autoimmunity to CII could play a crucial role not only in the initiation but amplification/perpetuation of inflammatory process in human RA.

• 대한치과보철학회지
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• 제38권5호
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• pp.583-594
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• 2000

Dislodgement of a crown or extension bridge and the loosening of a retainer of a bridge is a serious clinical problem in fixed restoration. Generally these problems are considered to be associated with deformation of the restoration. During biting, the restoration is subjected to complex forces and deforms considerably within the limit of its elasticity. Deformation of the restoration under the occlusal force induces excessive stress in the cement film, which then leads to the cement fracture. Such a fracture may eventually cause loss of the restoration. Because most of the past retention tests for full veneer crown were done without fatigue loading, they were not exactly simulating intraoral environment. And the purpose of this study was to evaluate the effect of cyclic cantilever loading on the retentive strength of full veneer crowns depending on different type of cements and taper of prepared abutment. Steel dies with $8^{\circ}\;or\;16^{\circ}$ convergence angle were fabricated through milling and crowns with the same method. These dies and crowns were divided into 8 groups. Group 1 : $16^{\circ}$ taper die, cementation with zinc phosphate cement, without loading Group 2 : $16^{\circ}$ taper die, cementation with zinc phosphate cement, with loading Group 3 : $8^{\circ}$ taper die, cementation with zinc phosphate cement, without loading Group 4 : $8^{\circ}$ taper die, cementation with zinc phosphate cement, with loading Group 5 : $16^{\circ}$ taper die, cementation with Panavia 21, without loading Group 6 : $16^{\circ}$ taper die, cementation with Panavia 21, with loading Group 7 : $8^{\circ}$ taper die, cementation with Panavia 21 without loading Group 8 : $8^{\circ}$ taper die, cementation with Panavia 21, with loading After checking the fit of die and crown, the luting surface of dies and inner surface of crowns were air-abraded for 10 seconds. The crowns were cemented to the dies, with cements mixed according to the manufacturer's recommendations. A static load of 5kg was then applied for 10 minutes with static loading device. Twenty-four hours later, group 1, 3, 5, 7 were only thermocycled, group 2, 4, 6, 8 were subjected to cyclic loading after thermocycling. Retentive tests were performed on the Instron machine. From the finding of this study, the following conclusions were obtained 1. Panavia 21 showed significantly higher retentive strength than zinc phosphate cement for all groups (p<0.05). 2. There was a significant difference in the retentive strength between $8^{\circ}\;and\;16^{\circ}$ taper for zinc phosphate cement(p<0.05), but no significant difference for Panavia 21 (p>0.05). 3. Cyclic loading significantly decreased the retentive strength for all groups(p<0.05). 4. For zinc phosphate cement, there was 35% reduction of the retentive strength after loading in the $16^{\circ}$ taper die, 25% in the $8^{\circ}$ taper die, and for Panavia 21, 21% in the $16^{\circ}$ taper die, 18% in the $8^{\circ}$ taper die.

• 대한치과보철학회지
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• 제45권2호
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• pp.203-215
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• 2007

Statement of problem: Titanium and its alloy, with their excellent bio-compatibility and above average resistance to corrosion, have been widely used in the field of dentistry. However, the excessive oxidization of titanium which occurs during the process of firing on porcelain makes the bonding of titanium and porcelain more difficult than that of the conventional metal-porcelain bonding. To solve this problem related to titanium-porcelain bonding, several methods which modify the surfaces, coat the surfaces of titanium with various pure metals and ceramics, to enable the porcelain adhesive by limiting the diffusion of oxygen and forming the adhesive oxides surfaces, have been investigated. Purpose: The purpose of this study was to know whether the titanium-porcelain bonding strength could be enhanced by treating the titanium surface with gold and TiN followed by fabrication of clinically applicable porcelain-fused-to-titanium crown Material and method: The porcelain-fused-to-titanium crown was fabricated after sandblasting the surface of the casting titanium coping with $Al_2O_3$ and treating the surface with gold and TiN coating followed by condensation and firing of ultra-low fusing porcelain. To compare with porcelain-fused-to-titanium crowns, porcelain-fused-to-gold crowns were fabricated and used as control groups. The bonding strengths of porcelain-fused-to-gold crowns and porcelain-fused-totitanium crowns were set for comparison when the porcelain was fractured on purpose to get the experimental value of fracture strength. Then, the surface were examined by SEM and each fracturing pattern were compared with each other Result:Those results are as follows. 1. The highest value of fracture strength of porcelain-fused-to-titanium crowns was in the order of group with gold coating, group with TiN coating, group with $Al_2O_3$ sandblasting. No statistically significant difference was found among the three (P>.05). 2. The porcelain-fused-to-gold crowns showed the highest value in bonding strength. The bonding strength of crowns porcelain-fused-to-titanium crowns of rest groups showed bonding strength reaching only 85%-94% of that of PFG, though simple comparision seemed unacceptable due to the difference in materials used. 3. The fracturing patterns between metal and porcelain showed mixed type of failure behavior including cohesive failure and adhesive failure as a similar patterns by examination with the naked eye and SEM. But porcelain-fused-to-gold crowns showed high incidence of adhesive failure and porcelain-fused-to-titanium crowns showed high incidence of cohesive failure. Conclusion: Above results proved that when fabricating porcelain-fused-to-titanium crowns, treating casting titanium surface with gold or TiN was able to enhance the bonding strength between titanium and porcelain. Mean value of masticatory force was found to showed clinically acceptable values in porcelain bonding strength in all three groups. However, more experimental studies and evaluations should be done in order to get better porcelain bonding strength and various surface coating methods that can be applied on titanium surface with ease.

• 대한소아치과학회지
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• 제34권3호
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• pp.430-437
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• 2007

현재 혼합치열 분석 방법으로 가장 널리 사용되고 있는 Moyers의 예측표나 Tanaka와 Johnston의 예측방정식은 북유럽 인종의 백인 자료를 바탕으로 만들어졌기 때문에 한국인에게 적용하기에는 무리가 있다. 또한 최근에는 이들이 제시한 하악 전치에 기초한 방법이 미맹출 견치와 소구치 폭경의 합을 예측하기 위한 최적의 예측인자인지에 대해서도 의문이 제기되고 있다. 본 연구의 목적은 한국인 집단을 대상으로 미맹출 견치와 소구치의 근원심 폭경을 예측하기 위한 최적의 예측인자가 어떤 치아의 조합인지 밝히고, 그 조합을 이용한 예측 방정식을 제시하며, 새로운 예측 방정식의 임상 적용을 위해 그 타당성을 검증하는 것이다. 완전한 영구치열을 가진 성인 178명(남자 108명, 여자 70명, 평균 나이 21.63세)의 자료를 기초로 예측방정식을 도출하였으며, 53명의 청소년(남자 25명, 여자 28명, 평균 나이 14.22세)으로 검증집단을 구성하여 그 타당성을 검증하였다. 그 결과 다음과 같은 결론을 얻었다. 1. 한국인 혼합치열기 청소년에서 미맹출 견치와 소구치 폭경의 합을 예측하기 위한 최적의 치아 조합은 상악 중절치, 하악 측절치, 상악 제1대구치 폭경의 합이었다($r=0.65{\sim}0.80$). 2. 상악 중절치, 하악 측절치, 상악 제1대구치 폭경의 합을 기초로 하고 부가적인 설명 변수로 성별과 악궁을 포함시켜 계산한 예측 방정식은 다음과 같이 계산되었다. 남자, 상악: $Y\;=\;0.332{\times}X_0\;+\;6.195$ 남자, 하악: $Y\;=\;0.332{\times}X_0\;+\;5.269$ 여자, 상악: $Y\;=\;0.332{\times}X_0\;+\;5.929$ 여자, 하악: $Y\;=\;0.332{\times}X_0\;+\;5.003$ 예측 방정식의 설명력은 64%였으며 표준오차(SEE)는 0.71mm였다. 3. 새로운 예측 방정식을 검증 집단에 적용하여 검증한 결과, 약 97%에서 실제 측정한 견치와 소구치 폭경의 합과 예측치와의 차이가 1mm 이하였다.