몰리브덴 퍼어말로이의 자기저항 효과에 관한 연구

장충근,유중렬,송재용,윤만영,박재형,손대락 경북대학교 센서기술연구소 1991 센서技術學術大會論文集 Vol.2 No.1

자기저항센서를 제작하기 위하여 Mo-permalloy(Ni:79.43%, Fe:14.47%, Mo:5.7%, Mn:0.38%, C:0.013%)를 슬라이드 그라스에 진공증착하여 sensor element를 제작한 후 포화자속밀도(B_(s)), 보자력(H_(c)), 자기이방성상수(K//), 자기저항변화율(ΔR/R)을 조사하였다. 진공증착된 permalloy 박막의 포화자속밀도는 0.746T 이었으며, 자화주파수 1kHz에서 보자력은 2.90A/cm(//),1.98A/cm(⊥) 이었고, 열처리 후에 1.79A/cm(//). 1.37A/cm(⊥)로 감소되었다. 한편 이 소자의 자기이방성상수는 1.38X10^(4)erg/cm^(3) 이었으며 5x1^(0-3)T의 자장변화에 대만 저항변화율(ΔR/R)은 2.0% 이었다. 앞으로 이 소자의 온도특성, 잡음특성 및 내열성 등을 조사하고자 한다. To fabricate magnetoresistive sensor, Mo-permalloy(Ni:79.43%, Fe:14.47%, Mo:5.7%, Mn:0.38%, C:0.013%) was evaporated on the slide glass. Saturation magnetic induction(B_(s)), coercive field strength(H_(a)), magnetic anisotropy constant(K), and magnetoresistance were measured for the fabricated samples. The evaporated samples show that saturation magnetic induction was 0.746T, and coercive field strengthes were 2,90A/cm(//) and 1.98A/cm(⊥), and this values were reduced to 1.79A/cm(//) and 1.37A/cm(⊥) respectively after annealing. For the measurement of coercive field strength, magnetizing frequency of 1kHz was used. For the fabricated sensor element, magnetic anisotropic constant was 1.38X10^(4)erg/cm^(3) and magneto-resistance change(ΔR/R) was 2.0% under the magnetic field change of 5X10^(-3)T, We will continue study on the characteristics for the temperature, heat resistance, and noise.

Impacts of Fluid Dynamics Simulation in Study of Nasal Airflow Physiology and Pathophysiology in Realistic Human Three-Dimensional Nose Models

De Yun Wang, MD, PhD,Heow Peuh Lee,Bruce R. Gordon 대한이비인후과학회 2012 Clinical and Experimental Otorhinolaryngology Vol.5 No.4

During the past decades, numerous computational fluid dynamics (CFD) studies, constructed from CT or MRI images, have simulated human nasal models. As compared to rhinomanometry and acoustic rhinometry, which provide quantitative information only of nasal airflow, resistance, and cross sectional areas, CFD enables additional measurements of airflow passing through the nasal cavity that help visualize the physiologic impact of alterations in intranasal structures. Therefore, it becomes possible to quantitatively measure, and visually appreciate, the airflow pattern (laminar or turbulent), velocity, pressure,wall shear stress, particle deposition, and temperature changes at different flow rates, in different parts of the nasal cavity. The effects of both existing anatomical factors, as well as post-operative changes, can be assessed. With recent improvements in CFD technology and computing power, there is a promising future for CFD to become a useful tool in planning, predicting, and evaluating outcomes of nasal surgery. This review discusses the possibilities and potential impacts, as well as technical limitations, of using CFD simulation to better understand nasal airflow physiology.

Synthesis, Characterization, Luminescence and Biological Activity of Two Lanthanide Complexes Involving Mixed Ligands

De-Yun Ma,Hai-Fu Guo,Liang Qin,Jun Xu 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.9

Two new isostructural dinuclear complexes, Ln2(4-cpa)6(bpy)2 (Ln = Eu (1); Tb (2), 4-cpa = 4-chlorophenylacetate, bpy = 2,2'-bipyridine), have been hydrothermally synthesized and characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis (TGA), powder X-ray diffraction and single-crystal X-ray diffraction. The lanthanide ions are bridged by two bidentate and two terdentate carboxylate groups to give centrosymmetric dimers with Ln···Ln separations of 3.967(2) and 3.956(3) Å, respectively. Each metal atom is nine-coordinate and exhibits a distorted tricapped trigonal prismatic geometry. Three-dimensional fluorescence spectra show that both 1 and 2 emit bright red and green luminescence at room temperature, with long lifetimes of up to 0.369 ms (at 614 nm) and 0.432 ms (at 543 nm), respectively. Moreover, poor luminescence efficiency has been noted for complex 2. The 4-Hcpa ligand and complexes 1-2 have been screened for their phytogrowthinhibitory activities against Brassica napus L. and Echinochloa crusgalli L., and the results are compared with the activity of quizalofop-P-ethyl.

Time-Dependent Optimal Heater Control Using Analytic and Numerical Methods

Yun-De Shen,Zhen-Zhe Li,Dong-Ji Xuan,Kwang-Su Heo,Seoung-Yun Seol 한국정밀공학회 2010 International Journal of Precision Engineering and Vol.11 No.1

Thermoforming is one of the most versatile and economical processes to produce polymer products. The drawback of thermoforming is difficult to control thickness of final products. Temperature distribution affects the thickness distribution of final products, but temperature difference between surface and center of the sheet is difficult to be decreased because of low thermal conductivity of ABS material. In the first step, it was found out that timedependent variation of heat affects to the temperature difference between surface and center. An analytic solution was studied because the optimization time is remarkably large when optimal design is directly carried out using the analysis code developed in a previous study. Duhamel’s Theorem was used in order to solve a one-dimensional heat conduction with a time-dependent boundary condition when neglecting the effect of natural convection, but the analytic solution was difficult to be applied when the boundary condition is complicate or noncontinuous. In the following step, an optimal heating profile expressed by exponential function was recommended from 8 simple optimal cases using Duhamel’s Theorem, but the analysis results show that the effect of natural convection must be considered under the condition of setting the heat fluxes as suitable values. In order to consider the effect of natural convection with suitable heat inputs, Finite Difference Method was used. Through investigation, the optimal results using Finite Difference Method show that the temperature difference between surface and center of the sheet can be remarkably minimized with satisfying Temperature of Forming Window.

Significance of Susceptible Gene Expression Profiles in Nasal Polyposis

De Yun Wang, MD, PhD 대한이비인후과학회 2008 Clinical and Experimental Otorhinolaryngology Vol.1 No.4

Nasal polyposis (NP) is a common chronic inflammatory disease of the rhinosinus mucosa and a complex disease with strong genetic and environmental components. During the past 10 to 20 yr, many studies have been performed to determine differential gene expression profiles between NP and normal nasal tissues, in order to identify susceptible genes that are associated with NP-related traits. Despite achievement in the identification of candidate genes and their associated pathogenic pathways, the large challenges remain as the genetic and molecular alterations required for its development and progression are still unclear. Therefore, the development of novel, powerful tools for gene discovery, and a closer integration of genetics and medical biology would provide valuable insight into the pathogenesis of NP. Nasal polyposis (NP) is a common chronic inflammatory disease of the rhinosinus mucosa and a complex disease with strong genetic and environmental components. During the past 10 to 20 yr, many studies have been performed to determine differential gene expression profiles between NP and normal nasal tissues, in order to identify susceptible genes that are associated with NP-related traits. Despite achievement in the identification of candidate genes and their associated pathogenic pathways, the large challenges remain as the genetic and molecular alterations required for its development and progression are still unclear. Therefore, the development of novel, powerful tools for gene discovery, and a closer integration of genetics and medical biology would provide valuable insight into the pathogenesis of NP.

Synthesis, Characterization, Luminescence and Biological Activity of Two Lanthanide Complexes Involving Mixed Ligands

Ma, De-Yun,Guo, Hai-Fu,Qin, Liang,Xu, Jun Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.9

Two new isostructural dinuclear complexes, $Ln_2(4-cpa)_6(bpy)_2$ (Ln = Eu (1); Tb (2), 4-cpa = 4-chlorophenylacetate, bpy = 2,2'-bipyridine), have been hydrothermally synthesized and characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis (TGA), powder X-ray diffraction and single-crystal X-ray diffraction. The lanthanide ions are bridged by two bidentate and two terdentate carboxylate groups to give centrosymmetric dimers with $Ln{\cdots}Ln$ separations of 3.967(2) and 3.956(3) ${\AA}$, respectively. Each metal atom is nine-coordinate and exhibits a distorted tricapped trigonal prismatic geometry. Three-dimensional fluorescence spectra show that both 1 and 2 emit bright red and green luminescence at room temperature, with long lifetimes of up to 0.369 ms (at 614 nm) and 0.432 ms (at 543 nm), respectively. Moreover, poor luminescence efficiency has been noted for complex 2. The 4-Hcpa ligand and complexes 1-2 have been screened for their phytogrowth-inhibitory activities against Brassica napus L. and Echinochloa crusgalli L., and the results are compared with the activity of quizalofop-P-ethyl.

Comparison of Three Kinds of Explants in Culture of Russian Wildrye Grass

Lan Yun,Jin-Feng Yun,De-Fu Liu 한국초지조사료학회 2009 한국초지조사료학회 학술대회논문집 Vol.2009 No.08

Thee kinds of explants, young spikes, immature and mature embryos, was compared in callus induction, embryogenic callus formation, differentiation and plant regeneration of Russian wildrye. Callus induction efficient of young spikes is highest. The imature embryos formed more somatic embryogenesis, and with highest frequency of embryogenic callus.

Association of Polymorphisms in Stress-Related TNFα and NPY Genes with the Metabolic Syndrome in Han and Hui Ethnic Groups

Bu, De-Yun,Ji, Wen-Wu,Bai, Dan,Zhou, Jian,Li, Hai-Xia,Yang, Hui-Fang Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.14

Background: Metabolic syndrome (MS) is a cluster of complicated disorders caused by the interactive influencing factors of heredity and environment, which predisposes to many cnacers. Results from epidemic research indicate that stress is tightly related to the pathogenesis of MS and neoplasia. This paper aims to investigate the association between psychological stress and MS with respect to the tumor necrosis factor alpha (TNF${\alpha}$) and neuropeptide Y (NPY) genes in the Han and Hui ethnic groups. Methods: All subjects for this case-control study matched strict enrollment criteria (nationality, gender and age) and lived in the city of Wu Zhong of Ningxia Province in China. The enrolled group contained 102 matched pairs of Hui ethnic individuals and 98 matched pairs of Han ethnic individuals. Enrolled subjects completed the general Symptom Checklist-90 (SCL-90). The TNF${\alpha}$-308G/A variant and NPYrs16147 polymorphism were detected in case (81 males, 119 females) and control (81 males, 119 females) groups by polymerase chain reaction (PCR) amplification. Results: Nine factors of the SCL-90 were found to be statistically different (p<0.05) between case and control groups. The homozygous mutant genotype (AA) and the mutant allele (A) of the TNF${\alpha}$-308G/A gene were less frequently observed in the control population compared to the case group. The odds ratio (95% confidence interval) in "Allele" for MS was 2.28 (1.47-3.53), p=0.0001, while "OR" was 1.11 (0.83-1.47), p=0.15, for the NPYrs16147 gene polymorphism. Conclusions: Psychological stress has been positively associated with MS. A previous study from our group suggested there were differences in the level of psychological stress between Hui and Han ethnic groups. Furthermore, we found that the stress-related TNF${\alpha}$ gene was associated with MS for both Han and Hui ethnic groups. In contrast, NPY may be a possible contributor to MS and associated cancer for the Han ethnic group.

대형구조물의 일부경간 합성보 철골매입길이 산정에 대한 연구

윤여진 ( Yun Yeo-jin ),허주연 ( Hu Ju-yun ),듀 ( N. Jean De Dieu ),홍원기 ( Hong Won-kee ) 한국구조물진단유지관리공학회 2014 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.18 No.2

Research on the Relationship Between Serum Levels of Inflammatory Cytokines and Non-small Cell Lung Cancer

Song, Xiao-Yun,Zhou, Shi-Jie,Xiao, Ning,Li, Yun-Song,Zhen, De-Zhi,Su, Chong-Yu,Liu, Zhi-Dong Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.8

Aims: This study was conducted to evaluate the levels of TNF-${\alpha}$, IL-6, IL-8 and VEGF in serum of patients with non- small cell lung cancer, for assessing their possible diagnostic and prognostic roles. Methods: We enrolled 48 patients newly diagnosed with non-small cell lung cancer and 40 healthy controls. TNF- ${\alpha}$, IL-6 and IL-8 levels were measured in the serum of all the subjects with specific radioimmunoassay kits, while EGF was analyzed by sandwich enzyme immunoassay techniques. Results: A statistically significant difference was observed between lung cancer patients and the control group regarding the values of TNF-${\alpha}$, IL-6, IL-8 and VEGF in serum. Moreover, TNF-${\alpha}$, IL-8 and VEGF levels were higher in patients with advanced stages compared to early stages. In addition, higher serum levels of TNF-${\alpha}$, IL-6, IL-8 and VEGF were found in smokers than in non-smokers, both in patients and controls. Conclusion: Serum levels of TNF-${\alpha}$, IL-6, IL-8 and VEGF were all elevated in lung cancer patients, suggesting that inflammatory cytokines could be jointly used as a screening tool. Though TNF-${\alpha}$, IL-8 and VEGF levels were related to advanced disease, long-term survival studies of NSCLC patients should be performed to confirm whether they can act as biomarkers of advanced disease. In addition, smoking would be an important contributor to the processes of inflammation and lung cancer.