Nickel 化合物의 EXAFS에 관한 硏究

朴鍾允,李悳源,文昌淳 성균관대학교 기초과학연구소 1985 論文集 Vol.36 No.2

At Sufficiently high photoelectron kinetic energies, typically above 50 ev from the absorption edge, phase shifts are insensitive to chemical environment. Determination of φ_j(k) for an atom pair in a given model system of known distance r_j^m enable the determination of distance r_j^u in an "unknown" system containing the same atom pair. In the paper we are using NiSe as the known system and NiSe_2 as the unknown system. By the chemical transferability of phase shift, the distance between Ni and Se estimated 2.38 Å in Nise_2.

분기사각 덕트 내의 유동 특성에 관한 실험적 연구

이덕구,이행남,박길문 朝鮮大學校 機械技術硏究所 2001 機械技術硏究 Vol.4 No.1

The flow characteristics in dividing regions of rectangular duct system are precise, therefore their classification is very important not only in industry but also in hydrodynamics. By now, many studies of flow characteristics in dividing regions have been performed, but flow characteristics by visualizations in dividing regions have not been studied. The present Particle image velocimetry exhibits instant velocity distributions, kinetic energy distributions and vorticity, etc of the total flow fields due to the development of the accurate visualization with optical laser and optical equipment. Also, Particle image velocimetry is accurate with the flows characteristics of the dividing region as continuous analysis is done using input equipment. This study analyzes average velocity vector field, average kinetic energy and x-axis stress distribution of dividing regions with flow characteristics for visualization of Particle image velocimetry measurements in a dividing rectangular duct.

자동차용 시로코팬의 유동특성에 관한 연구

이행남,박길문,이덕구,정한별,김건일,설재림 朝鮮大學校 機械技術硏究所 2005 機械技術硏究 Vol.8 No.1

The sirocco fan is used to get low noise, and it has been applied to a lot of industry field like the heat engine, the fluid instrument power plant, the food industry, environment industry etc... because there are not problems even it is mixed with a any kind of liquid, gas, and solid. The flow characteristics in sirocco fan are investigated by PIV. The experiment using PIV measurement for Test section's flow characteristics acquired velocity distribution, Condition : when sirocco fan in automobile air controller maximum 1450RPM, and a revolution is a variation (l)950RPM, (2)l100RPM, (3) 1250RPM. The agreement a experiment shows the validity of this study and the results of this study would be useful to the engineers who design for the flow systems

커피, 녹차, 홍차, 맥주 및 우리 나라 전통차의 질산염 함량에 관한 연구

손상목,박양호,문덕경 단국대학교 1998 論文集 Vol.32 No.-

In order to calculate the daily intake amount of NO_3 for Korean, it is necessary to evaluate the basic information on average NO_3 content in beverage & drinks like another major sources for NO_3 such as vegetables, milk, grain, fruit and water. This experiment was aimed to find out the average content of NO_3 in favorite drinks for Koreans, the content of NO_3 in 5 sorts of tea, 7 coffees, 5 beers and 14 Korean traditional teas were investigated by 3 manufacturers in 5 duplications. The NO_3 content in Korean traditional tea show between 15 and 49ppm, but Brown rice-Green tea and Green tea have lower value than Red tea, Duchung tea and Jasmine tea. The lowest concentration among the Korean traditional tea shows in the Tea water boiled with burned rice(Sungryung tea). Chrysanthemum tea has the highest value among the imported teas, but Yongjeongmyeong tea has the lowest one. Red teas imported from Sri Lanka. USA show 30-33ppm which is similar to Korean red tea. The NO_3 content in de-caffeined coffee has the lowest value ever, but instant coffee such as Maxim coffee and Choice coffee show 44ppm and 47ppm respectively, whereas Raspberry coffee and Hazelunt coffee show relatively low concentration between 20 and 24ppm. But beers have lower value in NO_3 content compared to another beverage such as tea, coffee and Korean traditional tea. There is no difference between Korean produced or imported beer in terms of NO_3 content, but the lowest value was shown in Heinecken beer.

흡입관에 부착된 이젝터내의 유동특성에 관한연구

이행남,박길문,모양우,이덕구,설재림,김건일 朝鮮大學校 機械技術硏究所 2004 機械技術硏究 Vol.7 No.2

The ejector is used to get low pressure, and it has been applied to a lot of industry field like the heat engine, the fluid instrument power plant, the food industry, environment industry etc. because there are not any problem even it is mixed with kinds of liquid, gas, and solid. The flow characteristics in diffuser are investigated by PIV and CFD. The agreement between numerical analysis and experiment shows the validity of this study and the results of this study would be useful to the engineers who design for the flow systems for heating, ventilation, air conditioning and wastewater purification plants.

흡입관에 부착된 디퓨저 효과에 대한 연구

김도태,이행남,박길문,이덕구,설재림 朝鮮大學校 機械技術硏究所 2004 機械技術硏究 Vol.7 No.1

The diffuser is used to get low pressure, and it has been applied to a lot of industry field like the heat engine, the fluid instrument power plant, the food industry, environment industry etc... because there are not any problem even it is mixed with kinds of liquid, gas, and solid. The flow characteristics in diffuser are investigated by prv and CFD. The experiment using PIV measurement for mixing pipe's flow characteristics acquired velocity distribution, .Condition : when mixing pipe's diameter ratio is 1:2.3, and the flux is Q₁ = 1.136 l/s, Q₂ = 1.706 l/s, Q₃ = 2.276 l/s . Based on the PIV and the CFD results, the flow characteristics in ejector are discussed, and it shows the validity of this study.

변형률 측정을 이용한 추진기관용 Al 합금의 파괴인성 평가

김재훈,김덕회,임동규,박성욱,문순일 한국산업안전학회 2002 한국안전학회지 Vol.17 No.3

The fracture toughness is evaluated by using CT(compact tension) and 3PB(thress point bending) specimens of A1 alloys for propulsive engine. To evaluate the static fracture toughness, strain gage method is used. The static fracture toughness obtained from the strain measurement is compared with the results by ASTM standard and FEM analysis. For the reliable evaluation of fracture toughness, strain gages are attached at various positions.

원자로압력용기장 용접열영향부의 미세조직 변화가 Magnetic Barkhausen Noise 거동에 미치는 영향

김주학,윤의박,문종걸,박덕근,홍준화 韓國非破壞檢査學會 1998 한국비파괴검사학회지 Vol.18 No.4

최근 자기적 특성의 변화가 재료의 미세조직적 상태에 민감하다는 보고가 있다. 재료의 미세조직은 상(phase), 결정립의 크기, 석출물 등의 다양한 인자로 구성되며, 본 연구에서는 이러한 인자들을 이용하여 재료의 특성과 Barkhausen noise(BN)의 관계를 연관시키기 위한 시도를 하였다. ASTM A 508 Gr.3 원자로압력용기강을 대상으로 용접열영향부의 미세조직적인 변화를 일곱가지 대표적인 영역으로 구분하였고, 각 영역에서의 미세조직과 기계적특성의 변화를 파악한 후, 각 조건별로 BN을 측정하였다. 통상의 보자력이나 잔류자화 같은 자기적 성질은 큰 변화가 없었지만, BN은 미세조직의 상태에 따라 현격한 변화를 보였다. 결정립과 석출물의 크기가 증가함에 따라 BN은 증가하였고, tempered martensite 보다는 tempered bainite 조직에서 높은 BN을 나타냈다. Recent study has demonstrated that some magnetic properties are sensitive to the microstructural state of material. The ASTM A 508 Gr. 3 reactor pressure vessel steel has various microstructural changes including martensitic and bainitic phases, and various sizes of grain and precipitates in the weld heat-affected zone (HAZ). To correlate the microstructural state with Barkhausen noise (BN), specimens were prepared through simulating various weld thermal cycles using a thermal simulator. The conventional magnetic properties, i.e. coercive force, remanence and maximum induction, did not change significantly. whereas the BN amplitude and energy during a magnetization cycle changed markedly with microstructural state. The BN increased with increasing grain and carbide sizes, and the tempered bainite structure showed higher BN parameter than tempered martensite.

Efficacy of Intracytoplasmic Sperm Injection for Leukocytospermia

강희규,--,--,--,--,--,--,--,-- THE KOREAN SOCIETY FOR BIOMEDICAL LABORATORY SCIEN 2004 Journal of biomedical laboratory sciences Vol.10 No.1

White blood cells (WBCs) are present in most human ejaculates, but abnormally high concentration of seminal leukocytes map reflect an underlying pathological condition. The World Health Organization (WHO) has defined leukocytospermia as status of more than 10^(6) WBC/mL of semen. The purpose of this study was firstly, to compare the outcomes between conventional IVF and ICSl in leukocytospermia, and secondly, to investigate whether ICSI may be an alternation treatment for patients with leukocytospermia. Total 346 cycles of conventional IVF and ICSI candidates underwent IVF cycles at Eulji Hospital Infertility Clinic. Semen Parameters including concentration, motility, morphology of spermatozoa and concentration of leukocytes were assessed from the raw ejaculates. There was no difference in sperm concentration, motility and morphology. The rates of fertilization and good embryo development from ICSI were significantly higher than those from conventional IVF in leukocytospermia (60.4% & 32.5% respectively for ICSI group and 44.4% & 28.5%, respectively for IVF group, P<0.001). The pregnancy rate after ICSI was also higher than that from conventional IVF (34.0% vs 29.1%. P<0.05). These results indicate that the presence of seminal leukocyes (>1×10^(6) WBC/mL of semen) is adversely related with fertilization, embryo development and pregnancy rate. Therfore the measurement of seminal leukocytes in routine semen analysis appears to be of prognostic value with regard to male fertilizing potential. In conclusion. it is suggested that ICSI is an alternative choice of treatment for patients with leukocytospermia.

Observation of sperm-head vacuoles and sperm morphology under light microscope

Park, Yong-Seog,Park, Sol,Ko, Duck Sung,Park, Dong Wook,Seo, Ju Tae,Yang, Kwang Moon The Korean Society for Reproductive Medicine 2014 Clinical and Experimental Reproductive Medicine Vol.41 No.3

Objective: The presence of sperm-head vacuoles has been suspected to be deleterious to the outcomes of assisted reproductive technology (ART). It is difficult to accurately distinguish morphologically abnormal sperm with vacuoles under a light microscope. This study was performed to analyze the result of the observation of sperm-head vacuoles using Papanicolaou staining under a light microscope and whether the male partner's age affects these vacuoles. Methods: Sperm morphology with vacuoles was evaluated using Papanicolaou staining and observed under a light microscope ($400{\times)$) in 980 men. The normal morphology was divided into three categories (group A, <4% of normal morphology; group B, 4%-14% of normal morphology; and group C, >14% of normal morphology). The criteria for the sperm-head vacuoles were those given in the World Health Organization manual. For the analysis of the age factor, the participants were divided into the following groups: 26-30 years, 31-35 years, 36-40 years, 41-45 years, and 46-50 years. Results: The percentage of sperm-head vacuoles increased with normal sperm morphology (group A vs. groups B, C) (p<0.05). In the case of the age factor, a statistically significant difference was not observed across any of the age groups. Conclusion: A majority of the sperm-head vacuoles showed a statistically significant difference among normal morphology groups. Therefore, we should consider the probability of the percentage of sperm-head vacuoles not increasing with age but with abnormal sperm morphology. A further study is required to clarify the effect of the sperm-head vacuoles on ART outcomes.