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.

심실중격결손증-치험 1예-

조광현,우종수,황윤호,이양행,박철호,김종성,김철호,이경순,조영일,박태인 인제대학교 1985 仁濟醫學 Vol.6 No.4

A successful treatment of infants and children with congenital heart defects depends upon several factors: diagnosis must be accurate, the operative technique, including techniques of perfusion and myocardial preservation, must be suited to the needs of patients and intensive cares, including accurate anesthesia, must be applied through all stages of investigation and treatment, i.e. before, during and after the operation. Recently we performed a open heart surgery successfully for a six-years old girl who had suffered from frequent upper respiratory tract infection and mild to moderate exertional dyspnea with congenital heart defects (ventricular septal defect, Kirklin type II, with patent foramen ovale). The operation and postoperative course were very smooth. And now we report this with review of literatures.

이온 주입이 금속의 일함수에 미치는 영향(Ⅱ)

백영환,김현경,강석태,황정남,이철주,최대선,정병두 연세대학교 자연과학연구소 1985 學術論文集 Vol.15 No.-

낮은 에너지 가속기를 제작하여 순도가 99.99%인 다결정 Ni에 Li^+ 이온을 7 keV의 에너지로 각 시료에 대한 이온주입율이 1.3×10^16atoms/㎠, 4.0×10^15atoms/㎠, 2.0×10^15atoms/㎠, 1.0×10^15atoms/㎠, 2.0×10^14atoms/㎠ 가 되도록 주입시킨 후 전자총과 억제 전위차형 에너지 분석기를 이용하여 일함수의 변화를 측정하였다. 이온 주입율이 2×10^15atoms/㎠보다 작을 때는 일함수가 1.9 eV까지 감소하였고 이온주입율이 4.0×10^15atoms/㎠보다 많을 때는 일함수가 2.8 eV까지 증가하였다. 이것은 Topping의 이론 및 Bauer의 실험결과와 일치함을 보였다. The changes in the work function of polycrystalline Ni with a purity of 99.99% due to Li^+ ions implanted using a low energy ion accelerator and retarding potential energy analyser(RPEA) have been studied. The implantation energy of the Li^+ ions is 7 keV and the implanted ion dose for the various samples are 1.3×10^16 atoms/㎠, 4.0×10^15 atoms/㎠, 2.0×10^15 atoms/㎠, 1.0×10^15 atoms/㎠ and 2.0×10^14 atoms/㎠. When the ion dose is less than 2×10^15 atoms/㎠ the, work function decreases to 1.9 eV, but when the ion dose is more than 4×10^15 atoms/㎠, the work function increses to 2.8 eV. These results are in good agreement with Topping's theory and Bauer's experiment.

다발성 골수종에서 신부전 발생의 위험인자 및 신기능 회복 예측인자

황현철 ( Hyun Chul Whang ),고은실 ( Eun Sil Koh ),김정관 ( Jeong Gwan Kim ),정성진 ( Sung Jin Chung ),신석준 ( Seok Joon Shin ),박철휘 ( Cheol Whee Park ),장윤식 ( Yoon Sik Chang ) 대한내과학회 2014 대한내과학회지 Vol.86 No.2

Background/Aims: Multiple myeloma (MM) is frequently accompanied by renal insufficiency, which has been regarded as a poor prognostic factor for MM. It is known that the incidence and characteristics of MM in Asia differ from those in Western countries. The aim of this study was to evaluate risk factors for renal impairment and to investigate reversible factors for renal failure in patients with MM. Methods: Patients newly diagnosed with MM from 2005 to 2008 were included. We investigated factors associated with renal insufficiency and those related to recovery from renal dysfunction after 12 weeks of treatment of MM. Results: Renal failure was recognized in 86 (39%) of 221 patients at diagnosis. In the binary logistic regression analysis, low hemoglobin (odds ratio [OR], 0.813; p = 0.02), high β2microglobulin (OR, 1.006; p < 0.01), and use of angiotensin-converting enzyme inhibitors (ACEi) (OR, 2.783; p < 0.04) at initial presentation were independent risk factors for renal failure in patients with multiple myeloma. After 12 weeks of treatment, 25 of 86 (29%) patients with renal failure had recovered renal function. Good response to chemotherapy (OR, 6.044; p < 0.01) and higher eGFR (OR, 1.084; p < 0.01) were associated with renal function recovery. Conclusions: Levels of hemoglobin and β2microglobulin, and use of ACEi were independent risk factors for the development of renal failure in MM patients. The response to chemotherapy and eGFR at diagnosis significantly influenced recovery of renal function. (Korean J Med 2014;86:190-197)

능동 감쇠층을 이용한 아크형태 쉘 모델에 대한 진동특성 연구

고성현(Seong Hyun Ko),박현철(Hyun Chul Park),박철휴(Chul Hue Park),황운봉(Woonbong Whang) 한국소음진동공학회 2002 한국소음진동공학회 학술대회논문집 Vol.2002 No.5

Venous Anastomosis with Dorsal Veins Using Additional Incisions after Wound Closure in Metacarpophalangeal Joint Level Replantation

Cho, Sang Hyun,Bahar-Moni, Ahmed Suparno,Whang, Jong Ick,Seo, Hyeung Gyo,Park, Hyun Sik,Kim, Ji Sup,Park, Hyun Chul The Korean Society for Microsurgery 2016 Archives of reconstructive microsurgery Vol.25 No.1

In cases of replantation, accurate closure of all structures, including bone, tendons, arteries, nerves, and veins is essential. Among these, the vein is a weaker structure and is damaged severely in most amputation cases. After fixation of bone, repair of tendons, nerves, and arteries, surgeons often experience difficulty in performing venous anastomoses. We found that in such cases, venous anastomosis is easy to perform using an additional incision after closure of the original wound. In a 33-year-old male patient with amputation of all four fingers at the metacarpophalangeal joint level, venous anastomoses were performed with dorsal veins using additional incisions after completion of the fixation of bones and repair of all other structures and closure of the skin due to surgical site tension.

여기상태의 원자를 투과한 Li 이온의 전하변환 단면적에 관한 연구

李鐵柱,高年奎,邊大鉉,黃正男 연세대학교 자연과학연구소 1979 學術論文集 Vol.3 No.-

본 실험에서는 10~60 keV의 에너지 범위에서 기저상태의 He, Ar 및 N_2와 여기 샹태의 He, Ar 및 N_2를 투과한 Li^+이온의 전자포획단면적 σ10와 σ10^*을 측정하였다. 기저상태의 표적물질에 대한 전하변환 단면적은 다른 사람들의 실험 결과 및 개량된 Rapp과 Francis의 이론값과 일치 하였다. 표적원자의 여기상태는 전자 충격법을 사용하여 생성시켰으며, 이때의 여기 단면적은 느린 전자검출법으로 측정하였다. 여기상태의 표적원자에 대한 전하변환 단면적 σ10^*는 기저상태에 대한 σ 보다, He에 대해서는 에너지가 적은 영역에서는 100배, 에너지가 많은 영역에서는 10배나 컸으며 Ar과 N^2에서는 30배에서 5배 정도 컸다. The electron capture cross sections σ10 and σ10^* of Li^+ in ground and metastable state He, Ar, and N_2 have been measured by the growth rate method in the energy range from 10 to 60keV. The cross section for ground state He, Ar and N_2 are in good agreement with other experimental results and with theoretical results from the Rapp and Franchis theory obtained by using an effective ionization potential and a modified impact parameter. The metastable stases of the target atoms were produced by the electron impact method and the excitation cross sections of He(2^3S_1), Ar(3^3P) and N_2 (A^3∑^+_u) were meaured by the trapped electron method. The σ10^* charge transfer cross sections for the metastable state are larger than the σ10 cross section for the ground state by a factor ranging from 10^2 in the lower energy region to 10 in the higher energy region in He, and from 30 to 5 in both Ar and N_2.

Detection of Hydrogen Produced in Molecule-Surface Interactions by Pd and FeNbTi Gate MOSFET

Lee, Chul-Chu,Chung, Won-Mo,Koh, Youn-Kyu,Whang, Chung-Nam,Kim, Hyun-Kyong 연세대학교 자연과학연구소 1981 學術論文集 Vol.7 No.-

Gate 금속으로 Pd와 FeNbTi를 사용하여 n-channel MOSFET를 제작하였고, 이들을 사용하여 물분자가 고온의 Pt 표면에 충돌할때 생성된 수소를 검출하였다. 이들 transistor의 threshold 전압변화는 공기중에 포함된 수소 분압에 따라 변화하였다. Pd-gate MOSFET는 40℃에서 50 ppm 이상의 수소량을 검출할 수 있었고 이때 반응 시간은 30초 정도이었다. FeNbTi-gate MOSFET의 수소검출감도는 Pd-gate MOSFET 보다 4배 정도 좋았다. 이들 transistor를 사용하여 물분자와 고온의 Pt표면과 상호작용에서 450 ppm 정도의 수소를 검출하였다. The n-channel MOSFETs with Pd and FeNbTi gates were designed and fabricated to detect hydrogen produced in water molecule-Pt surface interactions. The threshold voltages of these devices were found to be functions of the partial pressure of hydrogen in the ambient atmosphere. It was shown that the Pd-gate MOSFET has a sensitivity of 50 ppm hydrogen in air with a response time less than 30 sec at 40 ℃. The hydrogen detection sensitivity of the FeNbTi-gate MOSFET was found to be better than that of the Pd-gate MOSFET. About 450 ppm hydrogen produced in water molecule-hot Pt surface interaction was detected with the above devices.

臨床細菌學의 精度管理에 關한 硏究 : 細菌同定과 藥劑感受性檢査에 대하여 Identification and antimicrobial susceptibility test

郭賢淑,黃善哲,金仁仙,白承龍 고려대학교 의과대학 1980 고려대 의대 잡지 Vol.17 No.3

The clinical bacteriology concerns with the rapid and exact indentification of pathogenic bacteria from various clinical specimens. To obtain the correct results, quality assurance program, such as continuing education of the laboratory worker, documentation of laboratory procedures, control of media, susceptibility test, equipment and collections of stock organisms, and proficiency testing by government or any external agencies should be planned. Author tried both internal and external quality control program in clinical bacteriology of Korea University Hospital and 10 general hospitals, using 10 kinds of standard ATCC registered strains and already identified clinical isolates. The organisms were introduced in the condition of imitate blind specimens of single ATCC strain, or related species mixture. In addition, the antimicrobial susceptibility test was performed on S. aureus and E. coli ATCC strains. The results were as follows: 1. The correct identification of single ATCC strain was initially 52% in Korea University Hospital and 44% in 10 participating hospitals but the results improved to 82% and 70% in the fourth trials respectively. 2. The proficiencies of two strain mixture identification were less satisfactory than single strain identification and especially the identification of both organisms from two related species mixture was very poor. 3. The results of antimicrobial susceptibility test were relatively acceptable in S. aureus ATCC strain, but E. coli ATCC strain showed the results out of acceptable limits in Erythromycin, Chloramphenicol, Amphicillin and Cephalothin. 4. The proficiency according to the individual strain was about 60%, those of K. ozaenae, E. cloacae, and A. fecalis were less than 40%. 5. The proficiency of ATCC strains was high in E. coli, K. pneumoniae, and S. aureus, whereas the results of E. cloacae and S. marcescens were low.

Artifact-free Optical Spin-orbit Torque Magnetometry

Jung-Hyun Park,Joo-Sung Kim,Yong-Keum Park,Hyun-Seok Whang,Byoung-Chul Min,Sug-Bong Choe 한국자기학회 2019 한국자기학회 학술연구발표회 논문개요집 Vol.29 No.2