레드 저마네이트 단결정의 초전성 및 자발분극 변화

김일원 울산대학교 1987 연구논문집 Vol.18 No.2

실온에서 부터 Curie 온도까지 레드 저마네이트(Pb??Ge₃O??) 단결정의 초전계수를 이론식으로 부터 구한 값과 실험값을 비교하였다. 실온에서 레드 저마네이트 단결정의 초전계수 값은 2.5×10??C/m²℃이었고, 자발분극은 4.6μC/㎠이었다. 레드 저마네이트 단결정의 온도변화에 따른 초전계수는 Gibbs 자유에너지 이론과 이력곡선으로 부터 계산된 이론값과 실험값이 잘 일치하였다. The pyroelectirc coefficients of Pb??Ge₃O?? single crystals were obtained from room temperature to Curie temperature. At room temperature, the pyroelectirc coefficient and spontaneous polarization of Pb??Ge₃O?? single crystals were 2.5×10?? C/m²℃ and 4.6μC/㎠, respectively. The temperature dependency of the pyroelectric coefficient of Pb??Ge₃O?? single crystal was in good agreement with the results calculated from hysteresis loop and the Gibbs free energy theory.

폴리머 에멀젼 혼입에 의한 시멘트의 모르타르의 물성 변화 : Addition of EVAc Emulsion EVAc 에멀젼 첨가

김창은,김기일,김원기 연세대학교 산업기술연구소 1989 논문집 Vol.21 No.1

시멘트 모르타르에 EVAc 에멀젼 및 계면활성제(Sodium Dodecylbenzenesulfonate)를 첨가하여 압축강도, 흡수율, 화학적 저항성, 수화발열속도, 전자현미경 등으로 그 물성을 관찰하였다. EVAc를 시멘트에 첨가할 경우 5-15wt%, SDBF는 0.03wt%를 첨가하고 혼수량을 flow value로써 기준하는 것이 최적조건임을 알 수 있었다. 그리고 EVAc emulsion을 첨가하므로서 혼수량 및 흡수율의 감소효과를 거둘수가 있었으며 또한 화학적 저항성도 증가되었다. EVAc emulsion을 과다 첨가할 경우에는 강도가 저하하나, 여기에 계면활성제(Sodium Dodecylbenzenesulfonate)를 가하면 강도가 증가하였으며, 한편 수화 속도는 지연되었다. Properties of the cement mortar which mixed with EVAc emulsion and surfactant(Sodium Dodecylbenzene Sulfonate;SDBF) have been investigated by considering conpressive strength, water absorption, corrosion resistance, hydration heat evolution rate, and SEM. As a result, proper conditions were in the case of adding 5-15 wt% EVAc and 0.03wt% SDBF into cement mortar and determining water consistency by flow value. EVAc addition resulted in decreasing water consistency and water absorption, and increasing corrosion resistance of cement mortar. Strength of cement mortar decreased by adding excess EVAc. But strangth was increased and hydration rate was slowed by SDBF addition.

Ramsay-Hunt Syndrome 환자 1례에 대한 증례보고

김일수,송인선,유호상,손원택,오민석,송태원 대전대학교 한방병원 2001 惠和醫學 Vol.10 No.1

Ramsey-Hunt Syndrome occurs when herpes zoster after the facial nerve. It causes vesicular eruption of the pinna, external auditory meaturs and ear drum, severe otalgia with associated facial paralysis and vertigo. We experienced a case of Ramsay Hunt syndrome and managed it with oriental medicine's teatment and therapy of western medicine

LinbO₃단결정의 가열현상에 따른 자발분극 변화 및 초전계수

김갑진,김일원 울산대학교 1987 연구논문집 Vol.18 No.2

LiNbO₃단결정의 자발분극 변화량 △Ps와 초전계수 ?????를 25℃∼300℃ 온도 영역에서 측정하였다. 전극은 시료의 양극면에 silver paste를 사용하여 0.15㎠ 되게 하였다. 일정한 stress상태에서 시료의 온도를 연속적으로 변화 시켰다. 온도변화에 따른 자발분극 변화량은 op amp를 이용하여 결정극면에 나타나는 전하를 콘덴서에 축적하여 측정 하였다. 결정극면에 전기장이 없을 때 자발분극 변화량은 연속적인 온도의 함수로 측정하였다. 측정한 초전계수와 계산한 secondary 초전계수를 비교한 결과 LiNbO₃단결정의 초전성은 primary 초전현상에 기인하였다. 온도영역 100℃∼150℃ 사이에서 congruent한 c-plate시료에 나타나는 초전성의 불규칙한 변화는 분역들의 재정돈에 기인함이 확인되었다. 25℃∼300℃가지 LiNbO₃단결정의 자발분극 변화량은 2,858×10??C/㎠ 이었고 50℃에서 초전계수는 6.32×10??C/㎠℃ 이였다. Measurements of spontaneous polarization, Ps, and pyroelectric coefficient, dPs/dΘ, of LiNbo₃have been made over the temperature range from 25℃ to 300℃. Several crystals of typical surface area of 0.15㎠ were electroded with silver paste on the faces normal to the polar axis. The crystals were mounted in an unclamped manner and the temperature was varied continuously from 25℃ to 300℃. The change of spontaneous polarization as a function of temperature was obtained by integration the charge which appear on the polar faces of the crystal with an operational amplifier. With this arrangement the field across the crystal is essentially zero at all times, and the spontaneous polarization change can be recorded continuously as a function of temperature. After evaluating and comparing data, it becomes evident that the major pyroelectric properties of LiNbO₃, particulary in the temperature range, 25℃-300℃, belong to primary effect. The anomalous change of pyroelectric effect in LiNbO₃as grown crystal of congruent c-plate in the temperature region between 100℃-150℃ was due to the domain rearrangements. The change of spontaneous polarization is found to be 2.858×10??C/㎠ at 25℃-300℃ and pyroelectric coefficient for the LiNbo₃is measure to be 6.32×10??C/㎠℃ at 50℃.

加味行滯湯 合 六味地黃湯이 水銀(Hg)에 의한 家兎 肝組織損傷에 미치는 影響

金元一,金宇煥 동의대학교 한의학연구소 1998 동의한의연구 Vol.2 No.-

This study was carried out to determine whether Kamihaengche-Tang plus Yukmijihwang-Tang(KCYH) exerts the protective effect against Hg-induced white rabbit liver cell injury. Cell injury was estimated by measuring alanine aminotransferase (ALT) release, and lipid peroxidation was estimated by measuring malondialdehyde, a product of lipid peroxidation, in rabbit liver slices. Hg increased ALT release in dose-dependent manner over the range of 0.1-1 mM concentrations. Similarly, the drug also increased lipid peroxidation, indicating that Hg-induced liver cell injury was attributed to lipid peroxidation. When 0.5% KCYH was added to incubation solution, the cell injury and lipid peroxidation induced by Hg were markedly prevented. When liver tissues were treated with 0.5 mM Hg, cellular glutathione content significantly decreased. The addition of 0.5% KCYH to the medium increased, but not statistically significant, Hg-induced reduction in glutathione content. These results indicate that KCYH exerts the protective effect against Hg-induced liver cell injury, and this effect is attributed ti antioxidant action. However, the precise mechanisms of antioxidant effect of KCYH remain to be defined.

비글개에서 분만 후 자궁수복의 연속적 초음파상

손형원, 김홍석, 김형진, 김일화, 이기창, 이청산, 강현구 충북대학교 동물의학연구소 2006 Journal of Biomedical and Translational Research Vol.7 No.2

본문참고

중학교 과학교육에서 천체운동의 개념형성학습에 관한 연구

김순,강용희,안병호,윤일희,정원우 慶北大學校 師範大學 科學敎育硏究所 1999 科學敎育硏究誌 Vol.23 No.-

We consider the effect of conceptual learning through exploratory activities concerning the concepts of motion of celestial bodies in the middle school science class. We are also trying to show an improved way of teaching for the effective conceptual learning. To measure the effect of conceptual learning, we prepared a questionnaire with 17 test items concerning basic concepts of motion of earth and planets. The test scores for the conceptual learning group was significantly higher than those of the conventional learning group. Educational implications of the planned conceptual learning through exploratory activities are discussed.

Agrobacterium을 이용한 고추의 형질전환체계개발

최근원,박영두,박승국,전영주,유일웅,김인태,백운돈 경희대학교 생명자원과학연구원 1997 硏究論文集 Vol.18 No.-

본 실험은 고추의 형질전환체 선발을 위한 최소의 항생제농도를 결정하고 그 결과를 이용하여 형질전환체를 유기하고 효율을 최대화하기 위하여 수행한 바 그 결과는 다음과 같다. 1. 항생제 감응성 검정결과 kanamycin 40㎎/ℓ와 hygromycin 20 ㎎/ℓ에서 신초형성이 완전히 억제되었다. 2. Agrobacterium 제거에 사용되는 carbenicillin과 cefotaxime 처리시 재분화에 아무런 영향을 미치지 않았으며 cefotaxime 200㎎/ℓ 처리에서는 무처리구보다 신초형성이 더 활발하였다. 3. 회복친인 135Q와 276F에서는 형질 전환시 높은 재분화율을 보였으나 형질전환율은 각각 10%와 11.1%의 낮은 빈도를 보였다. 4. 재분화된 신초들을 대상으로 histochemical GUS assay를 실시한 결과 부분적으로 푸른발색이 확인되었다. 5. GUS활성을 보인 신초들에 대한 NPTⅡprimer를 이용한 PCR검정에서 NPTⅡ 유전자의 존재가 확인되었다. A transformation system using Agrobacterium tumefaciens was developed with different genotypes of hot peppers (Capsicum annuum). Four antibiotics commonly used in Agrobacterium-mediated transformation were tested for their effects on shoot regeneration. Shoot induction was completely inhibited by kanamycin at 40㎎/ℓ and hygromycin at 20㎎/ℓ or higher, but not by carbenicillin and cefotaxime. Cotyledon explants of hot peppers were cocultivated with Agrobacterium turnefaciens LBA4404 which carries a binary. vector pBI121 harboring the neomycin phosphotransferase, type Ⅱ (NPT Ⅱ) gene and β-glucuronidase (GUS) gene. For selection of transformed cells, 40㎎/ℓ kanamycin were used because the sensitivity test showed that 40㎎/ℓ kanamycin completely inhibited shoot induction from nontransformed cells. Histochemical GUS assay showed the presence of the GUS gene and PCR analysis confirmed the NP TⅡ gene was integrated. Transformation frequency was about 10.0% and 11.1% of total regenerants from 135Q and 276F, respectively.

민감도 분석을 이용한 겹치기 필릿용접의 용접변수 선정에 관한 연구

정재원,김일수,김학형,손성우,전광석 한국공작기계학회 2008 한국공작기계학회 추계학술대회논문집 Vol.2008 No.-

Arc welding process is one of the most important technologies to join metal plates. Robotic welding offers the reduced manufacturing cost sought, but its widespread use demands a means of sensing and correcting for inaccuracies in the part, the fixturing, and the robot. A number of problems that need to be addressed in robotic arc welding processes include sensing, joint tracking, and lack of adequate mathematical models for parameter prediction and quality control. Problems with parameter settings and quality control occur frequently in the GMA(Gas Metal Arc) welding process because of the large number of interactive parameters that must be set and accurately controlled. The objectives of this paper are to realize the mapping characteristics of bead width using a sensitivity analysis and multiple regression method, and finally select the most accurate model in order to control the weld quality(bead reinforcement area, bead penetration area) for lap joint fillet welding.

고등학교 지구과학 실험·실습 요목 비교 분석

정원우,이윤종,기우항,김영호,양승영,강용희,안병호,임성규,윤일희,김중욱,윤성효,강동진 경북대학교 과학교육연구소 1997 科學敎育硏究誌 Vol.21 No.-

The purpose of this study is to investigate the status of the experimental and practical education in high school earth. The present status and reasonable management of the experimental and practical education in high school earth science have been grasped from the questionaires. To do this, eighty eight earth science teachers in Korea are administered questionaires. The frequency of the experimental and practical items in the seven kind of earth science text books were investigated. The problems and the reasonable management for experimental and practical education were proposed in this paper.