• Title/Summary/Keyword: L-profiles

Search Result 862, Processing Time 0.036 seconds

HYDROGEN EMISSION SPECTRA OF QUIESCENT PROMINENCES

  • Kim, Kap-Sung
    • Journal of The Korean Astronomical Society
    • /
    • v.23 no.1
    • /
    • pp.71-82
    • /
    • 1990
  • Theoretical calculations of the combined radiative transfer and statistical equilibrium equation including the charge-particle conservations have been earned out for a multilevel hydrogen atom in quiescent prominences. Cool and dense models show the steep changes of population and radiation field in the vicinity of the surface, while these physical quantities remain unchanged for models with temperature of 7,300K, regardless of total densities. Ionization rate of hydrogen atom related with metallic line formation varies in considerable amounts from the surface to the center of model prominences cooler than 6,300K. However, such cool models cannot release enough hydrogen line emissions to explain observed intensities. Prominence models with a temperature higher than 8,000K can yield the centrally reversed Lyman line profiles confirmed by satellite EUV observations. We find that queiscent prominence with a density between $2{\times}10^{11}$ and $10^{12}cm^{-3}$ should be in temperature range between 6,300K and 8,300K, in order to explain consistently observed H alpha, beta line emissions and $n_p/n_l$ ratio.

  • PDF

Inelastic response of wide flange steel beams curved by symmetrical weak axis bending using two-point loads

  • Gergess, Antoine N.;Sen, Rajan
    • Steel and Composite Structures
    • /
    • v.17 no.6
    • /
    • pp.951-965
    • /
    • 2014
  • Point bending is commonly used for cambering and curving steel girders to large radii. In this system, a hydraulic ram or press is used to apply concentrated loads at selected points to obtain the required vertical (cambering) or horizontal (curving) curved profile from induced permanent deformations. This paper derives closed form solutions that relate loads to permanent deformations for horizontally curving wide flange steel beams based on their post-yield response. These solutions are presented in a parametric form to identify the relationship between key variables and their impact on the accuracy of the curving operation. It is shown that point bending could yield parabolic curved profiles that are within 1% of a desired circular curve if the span length to radius of curvature ratio (L / R) is less than 1.5 and the point loads are spaced at one third the beam length. Safe limits are then established on loads, strains and curvatures to avoid damaging the steel section. This leads to optimization of the point bending operation for inducing a circular profile in wide flange steel beams of any size.

Formulation of Erythromycin Enteric-coated Pellets (에리스로마이신 장용성 펠렛의 제제 설계)

  • 이승우;박은석;지상철
    • YAKHAK HOEJI
    • /
    • v.39 no.6
    • /
    • pp.593-599
    • /
    • 1995
  • Erythromycin was formulated as enteric-coated pellets in order to reduce degradation in stomach and gastromtestmal irritation, and to maximize the absorption in intestine followmg its oral administration. Core pellets were prepared using fluid-bed granulator with two different methods (powder layering and solvent spraying) and enteric-coated with two different coating polymers (HPMCP and Eudragit E30D). Physical characteristics md dissolution rates of core pellets and enteric-coated pellets were evaluated to optimize the formulation. Powder layering method resulted in shorter initial dissolution time than solvent spraying method, but physicochmical properties of the product were worse than solvent spraying method with respect to hardness, ftiability and density. The dissolution rate of the drug was increased with the addition of surfactants, showing concentration-dependence. The scanning electron microscopic observation of pellets revealed significant differences on the surface appearances prepared with solvent spraying method. The core pellet made with powder layering method had crystals on the surface, which resulted in poor physical properties of the pellets. The dissolution profiles of erythromycin pellets coated with HPMCP or Eudragit L30D were close to that of commercially available erythromycin enteric-coated product.

  • PDF

Effect of Glutamine on the Diclofenac Induced Bacterial Translocation and Lipid Peroxidation (Diclofenac에 의해 유발된 장내세균전위와 지질과산화에 대한 글루타민의 효과)

  • Kim, Eun-Jeong;Kim, Jeong-Wook
    • YAKHAK HOEJI
    • /
    • v.49 no.2
    • /
    • pp.128-133
    • /
    • 2005
  • The aim of this study was to examine whether administration of glutamine are able to prevent the NSAID induced bacterial translocation and lipid peroxidation in the rats. The an imals with glutamine were fed with L-glutamine for 5 days before diclofenac administration (100 mg/kg orally). 48 hour after diclofenac administration, intestinal permeability, serum biochemical profiles, and malondialdehyde levels of ileum were measured for evaluation of gut damage. Also, enteric aerobic bacterial counts, number of gram-negatives in mesenteric Iymph nodes, liver, spleen and kidney and malondialdehyde levels in liver, spleen, kidney and plasma were measured. Diclofenac caused the gut damage, enteric bacterial overgrowth, increased bacterial translocation and increased lipid peroxidation. Co-administration of glutamine reduced the gut damage, enteric bacterial overgrowth, bacterial translocation and lipid peroxidation induced by diclofenac. This study suggested that glutamine might effectively prevent non-steroidal anti-inflammatory drug induced bacterial translocation and lipid peroxidation in the rat.

THERMALLY INDUCED PHASE SEPARATION IN TERNARY POLYMER SOLUTION

  • Jung, Bum-Suk;Kang, Yong-Soo;Jones, Richard-A.L.
    • Proceedings of the Membrane Society of Korea Conference
    • /
    • 1999.07a
    • /
    • pp.79-82
    • /
    • 1999
  • Using Small Angle Light Scattering (SALS), the effect of quench depth on the kinetics of phase separation for ternary solution blends was investigated. The system was composed of two polymers (polystyrene and polybutadiene) and a solvent (toluene). The analyses of the early stage of phase separation were based of the Cahn-Hilliard theory [1,5]. Apparent diffusion coefficients and the fastest mode of fluctuations were evaluated, when quench depth of the system were varied near the critical composition of polymer. In the late stage of phase separation, the domain growth showed a power law with the 1/3 exponent, i.e. $q_m(t)~t^{-1/3}$. For comparison between real images and scattering profiles with time, the image of phase domains with time were obtained by using Laser Confocal Scanning Microscopy (LSCM).

  • PDF

A Pharmacogenomic Study on Regional Dependent gene Expression and Drug Permeability in Rat Intestine

  • Shin, Ho-Chul;Chung, Moon-Koo;Han, Sang-Seop;Duxin Sun;Gordon L. Amidon
    • Proceedings of the Korean Society of Toxicology Conference
    • /
    • 2003.10b
    • /
    • pp.155-156
    • /
    • 2003
  • RNA was isolated from mucosal tissue of the duodenum, jejunum, ileum and colon after perfusion. The gene expression profiles were measured using Affymetrix GeneChip(R) analysis. Prodrug valacyclovir permeability was 5-fold and 2-fold higher than the parent drug acyclovir in the jejunum and ileum, respectively.(omitted)

  • PDF

Stability of antineoplaston A10 in Aqueous Solution

  • Oh, In-Joon;Lee, Jeong-Min;Lee, Yong-Bok;Shin, Sang-Chul;Choi, Bo-Gil
    • Archives of Pharmacal Research
    • /
    • v.18 no.2
    • /
    • pp.75-78
    • /
    • 1995
  • The analysis method nad stability test of antineoplaston A10, a new anticancer drug candidate, were established. A10 and phenylacetyl- L-glutamine, one of the degradation products, can be detected by high-performance liquid chromatography. The degradation kinetics of antineoplaston A10 in aqueous solutions from pH 1 to 10 buffers were carried out at 40, 50 and 60.deg.C. Pseudo-first order kinetics were obtained throughout the entire pH ranges studied. The pH-rate profiles showed that antineoplaston A10 was very unstable in alkaline conditions and most stable at pH 4.

  • PDF

Evaluation of Blood Profile and Meat Color Using Houttuynia cordata Pellet in Duck Diets (오리사료에 어성초 펠렛 첨가 급여로 오리혈액성상과 육색도에 미치는 영향 평가)

  • Jeong, Yeon-Woo
    • Journal of Environmental Science International
    • /
    • v.30 no.5
    • /
    • pp.425-428
    • /
    • 2021
  • The present study evaluated the blood profile and meat color of ducks with Houttuynia cordata (H. cordata) pellets in their diets. In total, 120 pekin ducks (1-d-old) were used in a 42 d growth trial. Ducks were randomly allocated to six pens and exposed to three replicates of two treatments: (1) controls as basal diet and (2) basal diet + 2% H. cordata pellets (T1). Total-cholesterol, HDL-cholesterol, triglyceride contents or L* and b* vaules revealed significant difference (p>0.05) in compared with those in the controls; however, dietary supplementation of H. cordata pellets did not affect (p>0.05) LDL-cholesterol, VLDL-cholesterol and a* values. In conclusion, the inclusion of 2% H. cordata pellets improved HDL-cholesterol and meat color in duck breast and thigh meats, which further reduced other cholesterol values.

Chemical Weathering Characteristics of Red Saprolites at Granitic Hills in Yeongam, Southwestern Korea (한반도 남서부 영암의 화강암 구릉대 적색토의 화학적 풍화 특색)

  • Kim, Young-Rae
    • Journal of the Korean Geographical Society
    • /
    • v.47 no.3
    • /
    • pp.315-327
    • /
    • 2012
  • Red saprolites are appeared in granitic hills in Yeongam, Southern Korean Peninsula. These red saprolites were analyzed for their geochemistry, including CIA, A-CN-K and A-CNK-FM ternary plots, to understand the chemical weathering trend and rubefaction of the saprolites. These saprolites were compared with laterite profiles in Cameroon formed under humid tropical conditions. The red saprolites in Yeongam show commonly massive loss of CaO, $Na_2O$, but $K_2O$ is being slow. The red saprolites in Yeongam relative to laterite and kaolinite profiles of Cameroon and Spain show weak chemical alteration owing to slow removal of $K_2O$, but high mafic constituents, $Fe_2O_3$ and MgO, for most of the samples. In the saprolites of Yeongam, mafic oxides become enriched because of the fast and massive removal of alkali constituents, such as CaO, $Na_2O$ and $K_2O$, relative to other elements, resulting in rubefaction of the saprolites. It is found that the rubefaction of the saprolites is not necessarily proportional to chemical weathering intensity.

  • PDF