• Title/Summary/Keyword: 소화한계

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Cellular Immune Response of the Grasshopper, Euprepocnemis shirakii Bolivar Following Injection of Bacillus subtilis (세균(Bacillus subtilis)에 대한 등검은메뚜기(Euprepocnemis shirakii Bolivar)의 세포성 면역반응)

  • 장병수;문명진한성식여성문
    • The Korean Journal of Zoology
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    • v.35 no.3
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    • pp.383-394
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    • 1992
  • 비병원성 세균인 고acirlus subtilis(ATCC6633)를 등검은메뚜기(Euprepocnemis shr'rakii Bolivar)의 성충 복강에 주입한 후, 혈구의 반응양상을 투과전자현미경으로 관찰하였다. 세균에 대한 혈구의 면역반응은 plasmatocyte와 granulocyte에 의한 식 세포작용(phagocytosis)의 형태로 이루어졌으며, 결절형꽁(nodule formation)은 일어나지 않았다. 식 세포작용의 초기 반응은 혈구의 세포질 돌기가 돌출되 면서 이물질을 둘러싼 후, 원형질막과의 융합에 의해 식포가 형성되었고, 식포의 주변부에서는 일차 리소조옴의 집적이 관찰되었으며, 이런 과정은 세균 주입후, 10분 이내에 완료되었다. 일차 리소조옴은 세균 주입 후 1시간 이내에 식포의 한계막과 융합하여 이차 리소조옴을 형성하였으며, 소화된 이물질은 9시간 이내에 exocytosis에 의해 배출 되었다.

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Oscillatory Instabilities of Edge Flames in Solid Rocket Combustion (고체연료로켓에서 에지화염의 맥동 불안정성)

  • Kim Kang-Tae;Park Jun-Sung;Park Jeong;Kim Jeong-Soo;Keel Sang-In;Cho Han-Chang
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2006.05a
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    • pp.275-278
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    • 2006
  • Systematic experiments in $CH_4/Air$ counterflow diffusion flames diluted with He have been undertaken to study the oscillatory instability in which lateral heat loss could be remarkable at low global strain rate. The oscillatory instability arises for Lewis numbers greater than unity and occurs near extinction condition. The dynamic behaviors of extinction in this configuration can be classified into three modes; growing, harmonic and decaying oscillation mode near extinction. As the global strain rate decreases, the amplitude of the oscillation becomes larger. This is caused by the increase of lateral heat loss which ran be confirmed by the reduction of lateral flame size. Oscillatory edge flame instabilities at low global strain rate are shown to be closely associated with not only Lewis number but also heat loss (radiation and lateral heat loss).

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Value-added Chemicals Derived from Propane Using Heterogeneous Catalysts (불균일계 촉매를 통한 프로판 고부가화)

  • Yoon, Ji-Sun;Suh, Dong-Jin;Park, Tae-Jin;Cho, Young-Sang;Suh, Young-Woong
    • Clean Technology
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    • v.14 no.2
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    • pp.71-86
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    • 2008
  • In this review we discussed the effective ways to catalytically derive value-added chemicals from propane which has been utilized only as an energy source so far. Among various propane-derived products, the most valuable chemicals such as propylene and acrylonitrile were mainly focused herein. Propylene could be manufactured through oxidative dehydrogenation of propane using $O_2,\;CO_2$, etc. as an oxidant for the purpose of overcoming thermodynamic limitations of propane dehydrogenation. On the other hand, propane ammoxidation would be an alternative to propylene ammoxidation for producing acrylonitrile since propane is much cheaper than propylene as a starting material. Although effective $MoVTeNbO_x$ catalysts have been developed fur propane ammoxidation in recent years, more detailed studies should be thoroughly performed. In carrying out both oxidative dehydrogenation and ammoxidation of propane fur a long period, the most critical issue is definitely considered to find out the most active and selective catalysts, which makes it possible to commercialize both reactions into economically viable processes.

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A taxonomic Study of Lysimachia sect. Spicatae (Primulaceae) Based on Morphological Characters (형태학적 형질에 의한 까치수염속(Lysimachia) Spicatae절 식물의 분류학적 연구)

  • Kim, Jin Man;Tae, Kyoung-Hwan;Kim, Joo-Hwan
    • Korean Journal of Plant Taxonomy
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    • v.37 no.1
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    • pp.61-78
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    • 2007
  • The general morphological characters of Lysimchia sect. Spicatae were reviewed. From the results, numerical analyses were conducted based on 34 morphological characters from 14 populations of three species in Korea in order to investigate the key characters among the treated taxa and taxonomic delimitation and to discuss the systematic relationship. Habitat, leaf apices, presence or absent of hair on leaves, stipules, stems and bracts, branch of stems, kind of hair on floral axis and pedicels, shape of florescens were important diagnostic characters to identify the species. The relationship between Lysimachia clethoides and L. barystachys was more close than that of L. fortunei based on the quantitative characters. Also, a new key was made up from the result.

Research Trends of Technology Using Oxygen for Dehydrogenation of Light Alkanes (경질알칸의 탈수소 반응을 위한 산소활용기술 연구 동향)

  • Koh, Hyoung Lim
    • Applied Chemistry for Engineering
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    • v.27 no.2
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    • pp.128-134
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    • 2016
  • Due to the great development made in converting the shale gas into the more valuable products, research and commercialization for production technology of olefins like propylene, butenes, butadiene from light alkanes have been intensively investigated. Especially the technology using oxygen like oxidative dehydrogenation or selective hydrogen combustion to overcome thermodynamic limit of direct dehydrogenation conversion has been extensively studied and some cases of applying this technology to the plant scale was reported. In this review, we have categorized the technology into two parts; gas phase oxygen utilization technology and lattice oxygen utilization technology. The trends, results and future direction of the technology are discussed.

Ettect of Diets Containing Dried Whey and Chitin on Growth Rate of Broiler Chicks (Dried Whey와 Chitin의 첨가(添加)가 Broiler Chick의 성장(成長)에 미치는 영향(影響)에 관한 연구(硏究))

  • Lee, Mee-Sook;Mo, Su-Mi
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.14 no.2
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    • pp.192-201
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    • 1985
  • Two experiments, utilizing 204 broiler chicks of the Maniker strain, were conducted to study the effects of dried whey and chitin on the growth of chicks. In the first experiment, diets containing 5%, 10%, or 15% dried whey, or a control diet with no whey, were fed to chicks from 1 day to 4 weeks of age. There were no significant differences among the dietary groups, with respect to the rate of growth or protein or feed efficiency. In the second experiment, chicks were fed with diets containing no whey, 2% chitin, 20% dried whey, or 20% dried whey plus 2% chitin, from 1 day to 4 weeks of age. Adverse effects (diarrhea, crooked toes and enlarged cecum) were observed in the group fed 20% dried whey. The protein efficiency ratio (PER) and feed efficiency ratio (FER) tended to improve in the dietary groups with dried whey, as compared to the control group. No significant differences were observed in the total carcass nitrogen and lipid levels of dietary groups. But the chitin-supplemented diets tended to improve on the growth rate compared to the groups without chitin. The results of the two experiments suggest that the growing broiler chick can tolerate up to 15% dried whey in the diet, without any harmful effect on growth. Also, chitin may improve the poorer growth rate of chicks fed dried whey, but not all of the adverse effects of whey.

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Numerical Study on the Reacting Flow Field abound Rectangular Cross Section Bluff Body (사각 둔각물체 주위의 반응유동장에 대한 수치적 연구)

  • Lee, Jung-Ran;Lee, Eui-Ju
    • Fire Science and Engineering
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    • v.27 no.6
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    • pp.64-69
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    • 2013
  • The Numerical simulation was performed on the flow field around the two-dimensional rectangular bluff body in order to simulate an engine nacelle fire and to complement the previous experimental results of the bluff body stabilized flames. Fire Dynamic Simulator (FDS) based on the Direct Numerical Simulation (DNS) was employed to clarify the characteristics of reacting flow around bluff body. The overall reaction was considered and the constant for reaction was determined from flame extinction limits of experimental results. The air used atmosphere and the fuel used methane. For both fuel ejection configurations against an oxidizer stream, the flame stability and flame mode were affected mainly by vortex structure near bluff body. In the coflow configuration, air velocity at the flame extinction limit are increased with fuel velocity, which is comparable to the experiment results. Comparing with the isothermal flow field, the reacting flow produces a weak and small recirculation zone, which is result in the reductions of density and momentum due to temperature increase by reaction in the wake zone.

Study on the Innovation Process of the Satellite Industry (인공위성 산업의 기술혁신 과정에 관한 연구)

  • Seol, Myung Hwan;Choi, Jong-In
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.9 no.6
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    • pp.117-128
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    • 2014
  • This is the case study of SATREC INITIATIVE company which is the unique domestic production of commercial satellites. We examined the path and pattern for accumulation of technological capability and technology learning process. This case study show that the process of technological innovation and their influencing factors. First, the technological learning of the satellite industry follows the stage of technological acquisition, absorption, improvement and is embodied by the technological capability. Second, accumulated technological capability of the satellite industry influences the technology innovation. Third, the top management team(TMT) affects the technological learning and technological capability. Fourth, TMT has a moderating role between the technological capability and the performance of technological innovation. Finally, technological innovations in the small and venture business would be the source of technological capability and technological learning. The implications of this study are as follows. TMT has the very important role for the technological innovation and affect the technology development and the production. Also technology-based companies must gain a competitiveness advantage through technological learning and technological innovations for sustainable growth.

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A taxonomic study of the external morphology of the Korean Oldenlandia L. (Rubiaceae) (외부형태 형질에 의한 한국산 백운풀속(Oldenlandia L.)의 분류학적 연구)

  • Nam, Bo Mi;Jang, Yong Seok;Park, Myung Soon;Eom, Jeong Ae;Chung, Gyu Young
    • Korean Journal of Plant Taxonomy
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    • v.40 no.3
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    • pp.145-152
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    • 2010
  • The external morphological characters of the Korean Oldenlandia were reviewed, and numerical analysis of 25 quantitative characters carried out to evaluate the delimitation of the taxa. Among the qualitative characters, the leaf shape, inflorescence, pilose of insde corolla, expansion of capsule apex, and seed shape were used to delimit 5 species of Korean Oldenlandia. As the result of principal component analysis of quantitative characters, O. corymbosa, O. hirsuta and O. strigulosa were evidently separated on a two-dimensional plot by PC1 and PC2, and O. brachypoda and O. diffusa slightly overlapped. However, O. brachypoda was distinctly delimited from O. diffusa by the shape of calyx lobe, the lengths of pedicel, filament and stigma. Also each of those two species was in a group of its own by cluster analysis.

Numerical Study on the Effect of Range Surrounding Environment on Detecting Time for Cooking Oil Fire in Kitchen (주방내 조리용 기름 화재 발생시 레인지 주변 환경이 감지 시간에 미치는 영향에 대한 수치해석적 연구)

  • Lee, Jin-Woo;Ko, Gwon-Hyun;Ryou, Hong-Sun;Jang, Yong-Jun;Jung, Woo-Sung
    • Fire Science and Engineering
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    • v.24 no.1
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    • pp.134-139
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    • 2010
  • According to the "Yearbook of disaster response, fire safety and fire statistics (NEMA: National Emergency Management Agency)", approximately 34% of all fire is interior fire such as hotel, restaurant and residence and more than 53% of which is occurring in the kitchen. The evaluation of fire extinguishing system in the kitchen is performed in accordance with the "Korea Fire Equipment Inspection Standard (KOFEIS 0101-1)" which is using one environmental condition. However, only using one environmental condition is not enough to evaluate the performance of the automatic fire extinguisher in kitchen fire. So the study of fire detecting characteristic about various environmental condition needs. In this study, the numerical analysis is carried out about detecting time characteristic for various range's surrounding environment. As a result, it showed up to 100 s difference in the detection time depending on the position of the range. And detecting time also showed difference for on-off hood operation. From this results, it can be verify and improve the evaluation standard for the fire extinguishing system in kitchen fire.