• Title/Summary/Keyword: Alpha phase

Search Result 1,603, Processing Time 0.031 seconds

Analysis of α + 40Ca and α + 58Ni Elastic Scatterings at Elab = 240 MeV

  • Kim, Yong Joo
    • New Physics: Sae Mulli
    • /
    • v.68 no.12
    • /
    • pp.1324-1330
    • /
    • 2018
  • The elastic scatterings for the ${\alpha}+^{40}Ca$ and the ${\alpha}+^{58}Ni$ systems at $E_{lab}=240MeV$ have been analyzed within the framework of the Coulomb-modified Glauber model using two kinds of Gaussian density parameters for the target nuclei. The first one is to use Gaussian density parameters obtained from the root-mean-square radius. The second one is to use parameters calculated by matching the Gaussian density to the two-parameter Fermi density. The results with surface-matched Gaussian densities provide reasonable agreement with the experimental data, but the results without matching do not. The oscillatory structures observed in the angular distributions of both system can be interpreted as being due to the strong interference between the near-side and the far-side scattering amplitudes. The differences between the phase shifts obtained from the two methods are examined. We also investigate the effect of these differences on the differential and reaction cross sections, the transmission functions and the strong absorption radii.

Induction of Selective Cell Death of Oral Squamous Carcinoma Cells by Integrin α2 Antibody and EGFR Antibody (인테그린 α2와 상피성장인자수용체 차단항체의 저해작용을 통한 구강편평상피암 세포의 선택적 제거)

  • Choi, Yeon-Sik;Kim, Gyoo-Cheon;Yoon, Sik;Hwang, Dae-Seok;Kim, Cheol-Hun;Jeon, Young-Chan;Byun, June-Ho;Shin, Sang-Hun;Kim, Uk-Kyu
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.35 no.3
    • /
    • pp.143-154
    • /
    • 2013
  • Purpose: This study was to find efficacy of integrin alpha2 (${\alpha}_2$) and epidermal growth factor receptor (EGFR) as tumor marker of oral squamous cell carcinoma (SCC) and clarify the selective cell death effect of anti-integrin ${\alpha}_2$ and anti-EGFR on SCC cells, additionally testify conjugated gold nanoparticles (GNP) with air plasma for selective cell death of oral SCC. Methods: Expression of integrin ${\alpha}_2$, EGFR on human SCC cells (SCC25) were examined by western blot. SCC25 cells were treated with anti-integrin ${\alpha}_2$, anti-EGFR and analysed by Hemacolor staining, immunoflorescence staining, FACS flow cytometry. Conjugated GNP with integrin ${\alpha}_2$, EGFR antibody were treated by air plasma on SCC cells. Results: Integrin ${\alpha}_2$ and EGFR were over-expressed on SCC25 cells than normal lung WI-38 cells. The cell viability rate of SCC25 cells treated with anti-integrin ${\alpha}_2$, anti-EGFR was lower than WI-38 cells. The concentration changes of nucleus, releasing cytochrome c and apoptosis inducing factor (AIF) from mitochondria to cytosol were observed. The changes of proteins related with apoptosis were observed. Increase of bax, bcl-xL, activation of caspase-3, -7, -9, and fragmentation of PARP, DFF45 and decrease of lamin A/C in SCC25 cells were observed. In FACS, increase of sub-$G_1$ and S phase was observed. Cell cycle related proteins, Such as cyclin D1, cyclin dependent kinase (CDK) 4, cyclin A, cyclin E, CDK 2, p27 were decreased. After SCC25 cells treated with conjugatged GNP-Integrin ${\alpha}_2$, GNP-EGFR, additionally air plasma, the cell death rate was significantly increased. Conclusion: Integrin ${\alpha}_2$, EGFR were over-expressed in oral SCC cells. Anti-integrin ${\alpha}_2$, anti-EGFR in SCC25 cells induced apoptosis selectively. When GNP-anti integrin ${\alpha}_2$, GNP-anti EGFR were treated with air plasma on SCC25 cells, cancer cells were died more selectively. GNP-anti integrin ${\alpha}_2$, GNP-anti EGFR with air plasma could be treatment choice of oral SCC.

Magnetic Properties of Nanocrystalline $Fe_{76-x}Cu_1Mo_xSi_{14}B_9$(x=2,3) Alloys ($Fe_{76-x} Cu_1Mo_xSi_14B_9(x=2, 3)$ 초미세 결정합금의 자기적 특성)

  • Pi, W.K.;Noh, T.H.;Kim, H.J.;Kang, I.K.
    • Journal of the Korean Magnetics Society
    • /
    • v.1 no.1
    • /
    • pp.12-16
    • /
    • 1991
  • The effect of annealing on the magnetic properties and the microstructures of the amorphous $Fe_{76-x}Cu_1Mo_xSi_{14}B_9$(x=2,3) alloys were investigated. When annealed at 500${^{\circ}C}$ for 1hr, $8{\sim}9{\times}10^3$ of the effective permeability and 3~4 A/m of the coercive force were achieved upon crystallization to $\alpha$-Fe phase. And the average diameter of the $\alpha$-Fe grains was about 20nm. For the nanovrystalline ferromagnets. the fine grain size is the important requirement to obtain a good soft magnetic property. In this work, in order to get the finer grain size of $\alpha$-Fe phase, two-step annealing treatment was given. That is, following the low-temperature at $400{^{\circ}C}$ for 1~3hr, the high-temperature annealing at $500{^{\circ}C}$ for 1hr was carried out. As the low-temperature annealing time increased, the effective permeability increased to $1.2{\sim}1.7{\times}10^4$ and the coercive force decreased to about 2 A/m. And the grain size was observed to be smaller than 10nm. The increased permeability and the decreased coercive force were attributed to the reduced average crystalline anisotropy by the refinement of $\alpha$-Fe(Si) grains.

  • PDF

A Study on the Change in Microstructures of Traditional Forged High Tin Bronzes by Quenching (담금질 조건에 따른 방짜유기의 미세조직 변화 연구)

  • Lee, Jae-Sung;Jeon, Ik-Hwan;Park, Jang-Sik
    • Journal of Conservation Science
    • /
    • v.27 no.4
    • /
    • pp.421-430
    • /
    • 2011
  • Thermal conditions in practice at the traditional bronze workshop of the Korean Folk Village in Yongin were examined along with the microstructures of some high tin bronze objects made there. Laboratory experiments approximating the conditions of the workshop were also carried out and the results were compared. The operating temperature of the workshop furnace was measured to range from $750^{\circ}C$ to $850^{\circ}C$ while the surface temperature of an object, upon its removal from the furnace for additional thermo-mechanical treatments, was generally in the range of $600^{\circ}C$ to $685^{\circ}C$. This variation in working temperatures was reflected in varying microstructures developed upon quenching. The products of the Folk Village were found to consist of microstructures where the ${\alpha}$ grains of the Cu-Sn system were distributed in the background of different phases including the ${\beta}$-martensite phase, retained ${\gamma}$ phase, ${\alpha}+{\delta}$ eutectoid or their mixtures. This variability, which is also identified in objects made in ancient times as well as in our laboratory experiments, suggests that the actual thermal conditions given during the quenching treatments are much more complicated than is inferred from the temperature measurements. This paper will present detailed accounts of the thermo-mechanical treatments as observed in the high tin bronze workshop of the Korean Folk Village and discuss the evolution of varying microstructures in terms of the substantial variability involved in the implementation of the traditional forged high tin bronze technology of Korea.

Retention Behavior and Separation of Phenol Derivatives through Cyclodextrin Complexes in Reversed-Phase Liquid Chromatography (역상 액체 크로마토그래피에서 씨클로덱스트린 착물을 이용한 페놀유도체들의 머무름 거동 및 분리)

  • Moon, Young-Ja;Kang, Sam-Woo
    • Analytical Science and Technology
    • /
    • v.11 no.3
    • /
    • pp.179-188
    • /
    • 1998
  • The capacity factor of fifteen phenol derivatives was determined with respect to the concentration of ${\alpha}$- or ${\beta}$-cyclodextrin [CD], the type as well as the content of organic solvent in the mobile phase, and the temperature. The effect of the inclusion complex formation between solutes and ${\alpha}$- or ${\beta}$-cyclodextrin on their retention and selectivity has been investigated. The inclusion effect of ${\beta}$-cyclodextrin was the most effective in aqueous methanol, whereas only a poor effect was observed in aqueous tetrahydrofuran and aqueous acetonitrile. A plot of the reciprocal of the capacity factor against $[CD]_T$ gives a straight line and the dissociation constant, $K_D$ of the inclusion complex can be calculated from the slope. It was possible to estimate the $k_D$ values in 100% water from a linear plot of $pK_D$ vs. water content in the solution by extrapolation. The separation factor, ${\alpha}$, of two compounds has been found to be affected not only by the $[CD]_T$ but also by their $K_D$ values. Under optimum conditions, some mixtures of phenol derivatives were able to separate successfully.

  • PDF

Mossbauer Studies of the $H_2$ Reduction Effects On Magnetic Properties of Sr-Ba Substituted Hexgonal Ferrite (치환형 Sr-Ba 육방 페라이트들의 자기적 성질에 수소환원이 미치는 효과에 관한 Mossbauer 분광학적 연구)

  • 박재윤;권명회;이재광
    • Journal of the Korean Magnetics Society
    • /
    • v.9 no.1
    • /
    • pp.35-40
    • /
    • 1999
  • Sr substituted materials for some barium in M-type barium ferrite powder and Co-Ti substituted Sr-Ba hexagonal ferrite powder were prepared by citrate sol-gel method and 2 MOE sol-gel method these hexaferrite particles were reduced for 1hr in the hydrogen gas. The reduction temperatures were varied in the range of 250 $^{\circ}C$ to 500 $^{\circ}C$. X-ray diffraction patterns were measured using diffractometer with Cu $K_{\Alhpa}$ radiation. Mossbauer absorption spectra were measured with a constant acceleration spectrometer. We have focused on studying the origin of increasing $M_s$ by M$\"{o}$ssbauer spectroscopy. Ferrite particles which were sintered at 105$0^{\circ}C$ were found to be typical magnetoplumbite structure and single phase. XRD patterns with varying the reduction temperatures in $Sr_{0.5}Ba_{0.5}Fe_{10}O_{19}$ indicates ferrites particles become composite hexaferrites containing $\alpha$-Fe at T_{red}=350 \;$^{\circ}C$$. On the otherhand, it was found that $Co^{2+}$ ions and $Ti^{4+}$ ions in $Sr_{0.7}Ba_{0.3}Fe_{10}CoTiO_{19}$ prevent from changing $Fe^{3+}$ ions to $\alpha$-Fe during the $H_2$ reduction. Comparing Mossbauer results with XRD results, we have determined most of $\alpha$-Fe are reduced from $4f_{vi}$ sites and 12k sites of $Fe^{3+}$ ions. These $\alpha$-Fe phase bring the induced anisotropy and increase saturation magnetization $M_s$.TEX>.

  • PDF

A Study of Altered IL-6 and TNF-α Expression in Peritoneal Fluid of Patients with Endometriosis (자궁내막증 환자의 복강 액내 IL-6와 TNF-α의 변화 양상에 관한 연구)

  • Kang, Jeong-Bae;Lee, Young-Kyeong
    • Clinical and Experimental Reproductive Medicine
    • /
    • v.33 no.1
    • /
    • pp.45-52
    • /
    • 2006
  • Objective: Our purpose was to investigate the relationship between the levels of IL-6 and tumor necrosis factor-${\alpha}$ in the peritoneal fluid of women with and without endometriosis and infertile women. Methods: This study is prospective and case-control study in University hospital, enrolled thirty-four women with laparoscopic findings of minimal to severe endometriosis, and thirty-seven women with no visual evidence of pelvic endometriosis and with benign gynecologic disease. IL-6 and tumor necrosis factor-${\alpha}$ levels in peritoneal fluid were determined using commercial ELISA. IL-6 and tumor necrosis factor-${\alpha}$ concentrations were compared among women with and without endometriosis, and with infertile and fertile women, and then also compared according the revised American Fertility Society classification. Results: IL-6 and tumor necrosis factor-${\alpha}$ concentrations were higher than in the peritoneal fluid of women with endometriosis than in matched normal controls. Cyclic variations in IL-6 concentrations were seen in peritoneal fluid from patients with endometriosis: the concentrations in the secretory phase were significantly higher than those in the proliferative phase. The concentrations were higher than among of infertile women than in fertile women. A significant correlation between IL-6 and tumor necrosis factor-${\alpha}$ concentrations and endometriosis stage III and IV was noted. Conclusion: Increased levels of IL-6 and tumor necrosis factor-${\alpha}$ in patients with endometriosis in the peritoneal fluid may be relate to the pathogenesis of endometriosis suggesting that partially contribute to the disturbed immune regulation observed in patients with endometriosis.

Phase and microstructure of hot-pressed SiC-AlN solid solutions (열간가압소결에 의한 SiC-AIN 고용체의 상 및 미세구조)

  • Chang-Sung Lim;Chang-Sam Kim;Deock-Soo Cheong
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.6 no.2
    • /
    • pp.238-246
    • /
    • 1996
  • High-density SiC-AIN solid solutions were fabricated from powder mixtures of $\beta$-SiC and AIN by hot-pressing in the 1870 to $2030^{\circ}C$ temperature range. The reaction of AIN and $\beta$-SiC (3C) powder transformed to the 2 H (wurzite) structure appeared to depend on the temperature and SiC/A1N ratio and seeds present. The crystalline phases consisted of a SiC-rich solid-solution phase and an A1N-rich solid-solution phase. At $2030^{\circ}C$ for 1 h, for a composition of 50 % AIN/50 % SiC with a seeding of $\alpha$-SiC, the complete solid solution could be obtained and the microstructures are equiaxed with a relatively homogeneous grain size of 2 H phases. The variation of the seeding of $\alpha$-SiC in SIC-A1N solid solutions could be attributed to the transformation behaviour and differences in size and shape of the grains, as well as to other factors, such as grain size distributions, compositional inhomogeneity, and structural defects.

  • PDF

Isolation, Identification, and Characterization of Bacillus spp. from the Traditionally fermented Cheonggukjangs in the Gyeonggi and the Gangwon Provinces (경기.강원 지역의 전통발효 청국장으로부터 Bacillus균주의 분리 동정 및 특성 분석)

  • Lee, Nam-Keun;Jeon, Eun-Hee;Lee, Hyo-Jin;Cho, Il-Jae;Hahm, Young-Tae
    • Applied Biological Chemistry
    • /
    • v.49 no.4
    • /
    • pp.276-280
    • /
    • 2006
  • Traditionally fermented Cheonggukjangs were collected from Gyeonggi and Gangwon provinces and 22 strains were isolated and identified by using 165 rDNA sequences. Most of the identified strains were Bacillus subtilis and B. licheniformis, B. subtilis and B. licheniformis are dominant in the Gyeonggi area and B. licheniformis in the Gangwon area. In the growth pattern of the isolated strains, the duration of lag phase was generally 5 to 7 hours and stationary phase was reached after 23 to 40 hours of incubation. Total cell populations at the stationary phase were between $1{\times}10^6\;CFU/ml$ and $5{\times}10^7\;CFU/ml$. The fermenting ability of carbohydrates of isolates showed some differences among the regions. The isolated strains from Yong-In, Gyeonggi showed higher fermenting abilities with D-xylose, xylitol, D-tagatose and Methyl-$\alpha$-D-mannopyranoside. D-lactose, D-tagatose, D-xylose, Methyl-$\alpha$-D-mannopyranoside, amygdalin, arbutin, esculin and 2-keto-gluconate were well fermented with the An-Seong's strains; L-rhamnose, inositol, D-mannitol, D-sorbitol, celibiose and gluconate with the Kawang-Ju's stains; and D-lactose with the Odaesan's strains.

A Study on Properties Cu-Sn Matrix Used in Diamond Wheel for Grinding Glass (Diamond Wheel용 Cu-Sn 기지의 유리연삭에 미치는 특성에 관한 연구)

  • Choi, Sung-Kook;Suh, Hyung-Suck;Choe, Jeong-Cheol
    • Journal of Korea Foundry Society
    • /
    • v.12 no.4
    • /
    • pp.317-325
    • /
    • 1992
  • Diamond is the hardest material known to humans, also possesses the highest thermal conductivity and a very low thermal expansion coefficient. Therefore, these properties of diamond make them logical choices for many difficult grinding application. Bonding material is a very important factor to performance of a grinding wheel. Grinding glass constitutes one of the major application areas of diamond grinding wheels, and Cu-Sn tin bronze matrix is widely used as a metal bond of diamond wheel in grinding glass but these studies are rarely reported. The bronze test pieces excluding diamond are sintered by the method of hot sizing respectively at $600^{\circ}C$, $650^{\circ}C$, $700^{\circ}C$, with a composition(Cu-10wt%Sn) on ${\alpha}$ phase and two compositions(Cu-20wt%Sn and Cu-23wt%Sn) on ${\alpha}+{\beta}$ phase. The rupture strength of Cu-10wt%Sn is highest. The bronze bonded diamond wheels are manufactured by same conditions as the bronze test pieces. The results of grinding ratio of wheels are highest in case of Cu-10wt%Sn bonded wheel sintered at $650^{\circ}C$ and grinding power is highest in same composition sintered at $700^{\circ}C$.

  • PDF