• Title/Summary/Keyword: primary phase

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Isolation and Culture Characteristics of a Bacterial Symbiont from Entomopathogenic Nematode Steinernema galseri (Steinernema glaseri 곤충병원선충으로부터 공생박테리아의 분리 및 배양특성)

  • 박선호;유연수
    • KSBB Journal
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    • v.14 no.2
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    • pp.198-204
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    • 1999
  • Asymbiotic bacterium with highly effective toxins was isolated from entomopathogenic nematode Steinernema glaseri which has been widely used against various soil-inhabiting pests. The symbiont of S. glaseri was identified as Xenorhabdus nematophilus sp. by using several biochemical and physiological tests. When this strain was released into the hemolymph of insect larva, it produced highly toxic substances and killed the larva within 2 days. Two colony forms that differed n some biochemical characteristics were observed when cultures in vitro. Phase l colonies were mucid and difficult to be dispersed in liquid. Phase II was not mucoid and was easily dispersed in liquid. It did not adsorb neutral red or bromothymol blue. Rod-shaped cell size was highly variable between two phases, ranging 2-10 ${\mu}{\textrm}{m}$. It was also found that only infective-stage nematodes can carry only primary-phase Xenorhabdus in their intestine.

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Study on Two-Phase Flow generated by Two Jets with Height Difference (높이차가 존재하는 두 분류의 2상유동에 관한 연구)

  • 박상규;양희천;이용호
    • Journal of Advanced Marine Engineering and Technology
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    • v.24 no.1
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    • pp.88-93
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    • 2000
  • In this study, the mixing process of two-phase flow generated by two jets with height difference is analyzed. The primary jet is jetted on the condition of the state mixed pulverized solid particles with air. The height difference between the main jet and the secondary jet is changed into three kinds(0, 32.5, 47.5mm). The velocity vector field, concentration field and turbulent properties of solid particles are measured by using 3-Dimensional Particles Dynamics Analyzer. As the height difference of two jets through the two nozzles increases, the solid particle recirculation zone and the dense zone in the combustion chamber become large. The solid particle concentration at the center of the combustion chamber gets dense because the particle velocity remains slow due to the existence of the solid particle recirculation zone. The particle concentration in the combustion chamber can also be influenced by the hight difference of two jets.

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Seminiferous Epithelium Cycle of Crocidura shantungensis

  • Jeong Seung-Don;Lee Jung-Hun
    • Biomedical Science Letters
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    • v.11 no.4
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    • pp.545-553
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    • 2005
  • The present study provides descriptions of the cellular associations of the seminiferous epithelium cycle in the Crocidura shantungensis. The cycle of the seminiferous epithelium was divided into 14 stages, and developing spermatids were subdivided into 15 steps. The Golgi phase occurs the first two steps, and the cap phase had the next four consecutive steps. The acrosomal and maturation phases were consisted of steps $7\~14$, and the remaining one step consisted the spermiation phase. The Ad type of spermatogonia was observed whole stages, and Ap, In and B spermatogonia were observed from stage II to stage VI. The preleptotene, leptotene and zygotene of primary spermatocytes were observed from VII to XIV stages, and pachytene spermatocyte was observed from I to XII stages. The diplotene spermatocyte was observed XIII stages, and meiotic figures and secondary spermatocytes were observed stage XIV. Our results provide the foundation for a variety of future studies of the spermiogenesis of C. shantungensis.

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A New Method of Phase Transformation (새로운 위상변성 방법)

  • Sang Se Oh
    • 전기의세계
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    • v.13 no.3
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    • pp.38-41
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    • 1964
  • This thesis is aimed to obtain efficiently economically any desired phases and single phase transformer without unbalance by using only a new transformer, applying the theory of rotating magnetic field. The brief construction and principle is as floow: two pieces of similar ring cores, triangular cores or polygonal cores are located on the upper and lower sides with equidistance. And the some number of similar leg cores, shaped a square-pillar or a sylinder, are arranged at equidistant of the core section. Ring windings or polyphase windings of AC machines are adopted as a winding method on the upper and lower cores. Three phase AC is applied to the primary windings on these cores so that the rotating magnetic field is induced on the cores and this magnetic fluxes pass through each of the secondary windings on the leg-cores with some difference in time.

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Preparation of $BaTiO_3$ Fine Powders by Spray Pyrolysis Using Ultrasonic Atomization Technique (초음파 분무 열분해법에 의한 $BaTiO_3$ 미분말의 제조)

  • 조형진;이종흔;박순자
    • Journal of the Korean Ceramic Society
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    • v.28 no.11
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    • pp.851-858
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    • 1991
  • Spherical fine BaTiO3 powders with an average diameter of 0.3${\mu}{\textrm}{m}$ to 0.9${\mu}{\textrm}{m}$ are prepared at 100$0^{\circ}C$ by the ultrasonic spray pyrolysis of solutions containing Ba(NO3)2 and TiCl4. Experimental variables are adjusted to produce BaTiO3 powders and its effect on the phase, the size and the morphology of the particles are investigated by XRD, SEM, TEM. Each particle consists of small primary particles and has a hollow around its center. The dependence of particle diameters on the concentrations of source solutions indicates that metal salt precursors are dried to precipitate solid particles and decompose to form BaTiO3 phase without gas phase reactions.

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Potential Immunotherapeutics for Immunosuppression in Sepsis

  • Shin, Jinwook;Jin, Mirim
    • Biomolecules & Therapeutics
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    • v.25 no.6
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    • pp.569-577
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    • 2017
  • Sepsis is a syndrome characterized by systemic inflammatory responses to a severe infection. Acute hyper-inflammatory reactions in the acute phase of sepsis have been considered as a primary reason for organ dysfunction and mortality, and advances in emergency intervention and improved intensive care management have reduced mortalities in the early phase. However it has been recognized that increased deaths in the late phase still maintain sepsis mortality high worldwide. Patients recovered from early severe illness are unable to control immune system with sepsis-induced immunosuppression such as immunological tolerance, exhaustion and apoptosis, which make them vulnerable to nosocomial and opportunistic infections ultimately leading to threat to life. Based on strategies to reverse immunosuppression, recent developments in sepsis therapy are focused on molecules having immune enhancing activities. These efforts are focused on defining and revising the immunocompromised status associated with long-term mortality.

Conceptual Design of a Single Phase 33 MVA HTS Transformer with a Tertiary Winding (3차 권선을 고려한 단상 33MVA 고온초전도 변압기의 개념설계)

  • Lee, S.W.;Kim, W.S.;Hahn, S.Y.;Hwang, Y.I.;Choi, K.D.
    • Progress in Superconductivity
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    • v.7 no.2
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    • pp.162-166
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    • 2006
  • We have proposed a 3 phase, 100 MVA, 154 kV class HTS transformer substituting for a 60 MVA conventional transformer. The power transformer of 154 kV class has a tertiary winding besides primary and secondary windings. So the HTS transformer should have the 3rd superconducting winding. In this paper, we designed conceptually the structure of the superconducting windings of a single phase 33 MVA transformer. The electrical characteristics of the HTS transformer such as % impedance and AC loss vary with the arrangement of the windings and gaps between windings. We analyzed the effects of the winding parameters, evaluated the cost of each design, and proposed a suitable HTS transformer model for future power distribution system.

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A study on the thrust characteristics of three phase linear induction motor by frequency variation (주파수변환에 의한 3상 선형유도전동기의 추력 특성에 관한 연구)

  • Im, Dal-Ho;Kim, Hak-Lyun;Kang, Do-Hyun
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.73-76
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    • 1988
  • In this paper, the governing equation of the three phase linear induction motor is induced by the method that current in the primary winding is assumed as a current sheet. The steady state flux and the flux that is produced by end effect are mathematically analysed by electromagnetic equation. Each thrust of these flux is respectively induced. So in this paper, it is proved that linear motor is highly affected by end effect at high speed and speed-thrust characteristics of three phase linear induction motor are shown by frequency variation in the actual model.

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Effect of pH on the Preparation of Spherical Fine Zirconia Powders Using Gas-Liquid Phase Reaction (기액반응법을 이용한 구형 지르코니아 미분체 제조시 pH의 영향)

  • 김창현;이대희;이창섭;이병교
    • Journal of the Korean Ceramic Society
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    • v.34 no.10
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    • pp.1009-1014
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    • 1997
  • Ammonia gas was blown into the solution of zirconium ion to induce precipitation of supersaturated zirconium ion at gas-liquid interface with increase in pH. The influence of pH on the phase and particle size of precipitate and calcined powders has been investigated. At pH 4.5 of zirconium solution, maximum yield of 98.7% was obtained. Above pH 4.5, there was no more increase of yield. Above pH 5.5, large aggregates consisting of primary particles were observed in precipitate and calcined powders. At pH 4.5, almost aggregate-free fine spherical zirconia powders were obtained.

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The Simulation of Semicale Natural Circulation Test 5-NC-3,S-NC-4 Using RELAP5/Mod3.1

  • Kim, S. N.;W. H. Jang
    • Nuclear Engineering and Technology
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    • v.30 no.5
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    • pp.424-434
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    • 1998
  • RELAP5/Mod3.1 code was assessed with the semiscale experiment S-NC-3, and S-NC-4, which simulated the two-phase natural circulation and reflux condensation for the SBLOCA of PWR, respectively . Test S-NC-3 and S-NC-4 calculation results showed that RELAP5/Mod3.1 quite well describes the influence of steam generator secondary side heat transfer degradation on both two-phase natural circulation and reflux condensation. A comparison between the calculated and measured two-phase mass flow rate in test S-NC-3 shows good agreement for primary mass inventory more than 92%. And RELAP5/Mod3.1 have a good mass flow rate prediction capability for the transient such as S-NC-4 except some flow oscillations. The reflux flow rate for S-NC-4 test is under predicted, and the overall results verify that the correct prediction of the reduced liquid level appears to be required for the correct calculation of the overall phenomena.

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