• 제목/요약/키워드: Middle wall

검색결과 375건 처리시간 0.022초

The Middle Lamella Remainders on the Surface of Various Mechanical Pulp Fibres

  • Li, Kecheng;Tan, Xuequan;Yan, Dongbo
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.1
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    • pp.51-59
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    • 2006
  • The surface of various mechanical pulp fibres including thermomechanical pulp (TMP), chemithermomechanical pulp (CTMP), and alkaline peroxide mechanical pulp (APMP) fibres, were characterized using SEM, AFM, and XPS. With SEM and AFM, middle lamella material was observed to be non-fibrillar, patch-like, while fibre secondary wall was observed to have a microfibrillar structure. It was found that after the first-stage refiner, lignin-rich middle lamella remainders are present on the fibre surface of all three pulps, although most of the fibre surfaces expose microfibrillar structure. After the final-stage refining, large amounts of granules are present on the TMP fibre surface. In contrast, most middle lamella remainders remain on the surface of CTMP fibres after final stage refining and even after peroxide bleaching. XPS results have confirmed that the non-fibrillar surface material is the lignin-rich middle lamella remainder., and the remainders of middle lamella contribute to the high surface lignin concentration.

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지형, 지세가 성곽축성 높이에 미친 영향 -수원화성을 중심으로- (The Effects of Geographical Features and Configuration on the Height of Castle Wall - The Case of Hwasong in Suwon City)

  • 박춘균;이재근
    • 한국조경학회지
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    • 제28권1호
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    • pp.1-10
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    • 2000
  • The main purpose of this research is to show the consideration of the geographical effects related with its features and configuration on the height of the wall in Hwasong. The method of this research is based on old documentary records and actual measuring. The result of this research is to take advantage of nature geographical features and configuration. First the castle of wall construction is based on outside defensive protection, mainly it was made of stones or bricks. And took advantage of its natural environment. According to circumstance, there were two kinds of general method to build the wall., Second It was considered, They had so many difficulty to move stones to build wall, especially to rugged hilly steep mountain. Third There were three kinds of stones to build wall, Bottom stones were piled with Big stones, because of its stability. Third There were three kinds of stones to build wall, Bottom stones were piled with Big stones, because of its stability. On top of the wall was built with small stones it shows good harmony with small, middle, big size stones. It is considered not only stability but also beauty of appearance. Fourth Placing ChiSung was able to adjust height of wall low at the same time it was also taken advantage of a active defensive power. The suggestion of this research is to take advantage f nature geographical features and at the same time it was a perfect way to save the cost of construction. The further research of this should be continued to deepen because, it is the early stage, so it is maningful of eoffering a guidance for the furder research. in this research has a number of important question remain unsolved.

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석탄화력발전소 보일러의 멤브레인벽을 위한 등가 쉘요소의 직교이방성 탄성상수 결정 방법 (Method for Determining Orthotropic Elastic Constants of Equivalent Shell Elements for the Boiler Membrane Wall of Coal-Fired Power Plants)

  • 이부윤
    • 한국기계가공학회지
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    • 제19권3호
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    • pp.77-85
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    • 2020
  • In this study, we proposed a method to replace the solid finite element model of the boiler membrane wall for coal-fired power plants using an equivalent shell model. The application of a bending load to the membrane wall creates greater displacement at both ends of the central portion when compared with the middle when an isotropic elastic constant is used in the shell model. This is inconsistent with the results of the solid model where the central portion is uniformly deformed. Here, we presented a method to determine the orthotropic elastic constants of the shell model in terms of bending stiffness and vibration characteristics to solve this problem. Our analysis of the orthotropic shell model showed that the error ratio was 0.9% for the maximum displacement due to the bending load, 0.3% for the first natural frequency, and 2.5% for the second natural frequency when compared with the solid model. In conclusion, a complicated boiler membrane wall composed of a large number of pipes and fins can be replaced with a simple shell model that shows equivalent bending stiffness and vibration characteristics using our proposed method.

전통주택의 다락에 관한 연구 - 전북지방을 중심으로 - (A Study on the Loft in Korean Traditional Houses - Focused on the Chun-Buk Province -)

  • 최인호
    • 한국주거학회논문집
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    • 제8권2호
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    • pp.1-15
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    • 1997
  • This study is purpose to analyze and adjust structure and composition methodology for Loft of korean traditional houses and than studying correlation about housing plan, according to middle-story structure like Loft form housing architecture. The Loft is composited to level by condition of location, using a rise of stair by expanding of span by function. We can divide to condition of location flatland and slant. In the flatland case, Loft is so heating that the kitchen floor make a lowly and in the slant case, Loft is composited a part of wing using height attitude of floor when the house build type and ㅁ type. Through this study. the Loft is various form of this structural forming then is affect the house facade. The composite of wall is come with the existence of Loft and the wall divided by the lintel and wall line.

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Free vibration of core wall structure coupled with connecting beams

  • Wang, Quanfeng
    • Structural Engineering and Mechanics
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    • 제10권3호
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    • pp.263-275
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    • 2000
  • In this paper, a core wall structure coupled with connecting beams is discretized and modeled as an equivalent thin-walled member with closed section, while the connecting beams between openings are replaced by an equivalent shear diaphragm. Then, a numerical method (finite member element method, FMEM) for dynamic analysis of the core wall structure is proposed. The numerical method combines the advantages of the FMEM and Vlasov's thin-walled beam theory and the effects of torsion, warping and, especially, the shearing strains in the middle surface of the walls are considered. The results presented in this paper are very promising compared with the ones obtained from finite element method.

김치의 조직에 미치는 솔잎 물추출물의 첨가 효과 (Effect of Addition of Water Extract of Pine Needle on Tissue of Kimchi)

  • 김순동;오영애;김경희
    • 한국식품영양과학회지
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    • 제27권3호
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    • pp.461-470
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    • 1998
  • The effects of addition of water extract of pine needle(WEPN) on texture and cell wall polysac-charides content of kimchi during fermentation at 1$0^{\circ}C$ were investigated. Textural properties of hardness, gumminess and cohesiveness of kimchi were higher for WEPN-added kimchi than for the control during the entire fermentation periods, while its adhesiveness was lower. Alcohol insoluble substance, among cell wall polysaccharide fractions of kimchi was higher in WEPN-added kimchi than in the control but water soluble materals was high in control during fermentation periods. The separation phenomenon of middle lamella of control kimchi tissue was observed at 14th days of fermentation but WEPN-added kimchi showed at 21th days fermentation. The vasular of kimchi tissue was more destroyed in control than in WEPN-added kimchi.

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Lateral loading test for partially confined and unconfined masonry panels

  • Tu, Yi-Hsuan;Lo, Ting-Yi;Chuang, Tsung-Hua
    • Earthquakes and Structures
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    • 제18권3호
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    • pp.379-390
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    • 2020
  • Four full-scaled partially confined and unconfined masonry panels were tested with monotonic lateral loads. To study the effects of vertical force and boundary columns, two specimens with no boundary columns were subjected to different vertical forces, while two wing-wall specimens had the column placed eccentrically and in the middle, respectively. The specimens with no boundary columns exhibited ductile rocking behavior, where the lateral strength increased with increasing vertical compression. The wing-wall specimens with columns behaved as strut-and-tie systems. The column-panel interaction resulted in greater strength, lower deformation capacity and differences in failure modes. A comparison with analytical models showed that rocking strength can be accurately estimated using vertical force and the panel aspect ratio for panels with no boundary columns. The estimation for lateral strength on the basis of a panel section area indicated scattered error for wing-wall specimens.

벽걸이형 스피커 거치대 형상에 따른 구조강도 해석 (Structural strength analysis according to the configuration of speaker placer with wall hanger type)

  • 조재웅;한문식
    • 한국기계가공학회지
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    • 제12권1호
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    • pp.1-8
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    • 2013
  • This study investigates life and damage due to structural and fatigue load at speaker placer with wall hanger type. As the small stress and deformation are shown at the models of A, B and C shapes on structural analysis, there is no problem at installing speaker placer. As the largest stress is happened at the middle part of joint on the models of A, B and C shapes, this part must be considered at the design. A shape is thought to have most fatigue damage among 3 shape models. C shape model has most excellent, but A model has least at fatigue durability. This study result is applied with the design of speaker placer and it can be useful at predicting prevention and durability against its damage.

Strengthening of deficient RC frames with high strength concrete panels: an experimental study

  • Baran, Mehmet;Susoy, Melih;Tankut, Tugrul
    • Structural Engineering and Mechanics
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    • 제37권2호
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    • pp.177-196
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    • 2011
  • An economic, structurally effective and practically applicable strengthening technique was developed for reinforced concrete (RC) framed buildings. The idea of the technique is to convert the existing hollow brick infill wall into a load carrying system acting as a cast-in-place RC infill wall by bonding relatively thin high strength precast concrete PC panels to the plastered hollow brick infill. For this purpose, a total of eight one-third scale, one bay, one story frames were tested under reversed-cyclic lateral loads. Test frames were designed and constructed with common deficiencies observed in practice. Four different panel types were used for strengthening. Test results showed that both strength and stiffness of the frames were significantly improved by the introduction of PC panels. Experimental results were compared with the analytical approaches suggested by the authors.

복숭아의 품종과 숙도에 따른 세포벽 성분, 효소활성 및 조직의 변화 (Changes in the Cell Wall Components, Enzyme Activities and Cell Structure of Peach during Maturation)

  • 김미현;신승렬
    • 한국식품저장유통학회지
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    • 제1권2호
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    • pp.107-116
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    • 1994
  • This paper was carried out to Investigate changes in the activities of cell-degrading enzymes, cell wall components and cell structure of peach during maturation and storage for valuation of quality. The firmness of peach was decreased during maturation and storage, and was remarkably decreased in Daegubo than Yumyung. Polygalacturonase and $\beta$-galactosidase activities of peach were increased during maturation and storage, and were remarably increased in soft peach and in mature and soft peach, respectively. Contents of alcohol-insoluble substance, cell wall, and total and insoluble pectin of peach were decreased during maturation and storage, but cellulose and soluble pectin were increased. Intracellular space was enlarged during maturation and middle lamella was gradually degraded during maturation.

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