Mechanism of Cumulative Damage to Short Fiber type C/SiC under Tension

A cumulative damage mechanism for short fiber type C/SiC during shear loading–unloading testing was examined and quantified using Iosipescu specimens parallel in the in-plane and through-thickness plane, and by using modified fracture and damage mechanics theory referring to measured damage characteristics (crack length, number and angle). A nonlinear stress–strain relation was found for both specimens. Decrease in the apparent modulus was confirmed with increased peak stress, although permanent strain increased. Inelastic strain of the decomposed tensile direction derived from shear stress was greater than that of the compressive one. Cracks propagated perpendicularly to the tensile direction, intruding on the boundary of the transverse fibers and connecting to other cracks. The theoretical damage mechanics model succeeded to predict the stress–strain relation, proposing that the shear mechanical properties are predictable by measuring the damage characteristics.

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Analysis of Additive Alignment in a 90∘ Elbow Channel

International Journal of Air-Conditioning and Refrigeration ◽

10.1142/s2010132520500327 ◽

2020 ◽

Vol 28 (04) ◽

pp. 2050032

Author(s):

Hoang Minh Khoa Nguyen ◽

Dong-Wook Oh

Keyword(s):

Flow Visualization ◽

Fiber Type ◽

Weight Ratio ◽

High Strength ◽

Short Fiber ◽

Industrial Applications ◽

Injection Molding Process ◽

Molding Process ◽

Corner Region ◽

Liquid Polymer

Short-fiber reinforced polymer composites have been widely used in industrial applications due to high strength-to-weight ratio, versatile manufacturing process, and etc. The alignment of fiber type additives plays an important role in the mechanical properties of a composite material. In this paper, an injection molding process was imitated with a liquid polymer composite flow inside a [Formula: see text] elbow channel. We performed a flow visualization experiment and analyzed the additive alignment of carbon fiber flowing in the polydimethylsiloxane (PDMS) medium. By analyzing the flow visualization images, the angle changes at the corner region of the elbow channel were calculated. At the corner region, the change of passage direction leads to the change of fiber orientation. It was observed that near to the convex region, fibers have angle change values larger than the fibers traveling near to the concave region.

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Short-Fiber-Reinforced Elastomer Composites

Rubber Chemistry and Technology ◽

10.5254/1.3535189 ◽

1977 ◽

Vol 50 (5) ◽

pp. 945-958 ◽

Cited By ~ 106

Author(s):

J. E. O'Connor

Keyword(s):

Fiber Type ◽

Cellulose Fibers ◽

Short Fiber ◽

Bonding Agents ◽

Fiber Dispersion ◽

Adhesion Promoters ◽

Fiber Aspect Ratio ◽

Matrix Adhesion ◽

Glass Carbon ◽

Fiber Matrix

Abstract The reinforcement of elastomers with short fibers results in composites with a wide variety of properties. The performance and properties are a function of fiber type, fiber content, fiber aspect ratio, fiber orientation, fiber dispersion, fiber-matrix adhesion, processing methods, and properties of the elastomer matrix. A composite with almost any desired property can be obtained by manipulation of these parameters. Of the five fibers studied in this work, glass and carbon are the poorest for increasing mechanical properties. The cellulose, aramid, and nylon fibers all reinforce elastomers to give composites of approximately the same magnitude in properties. Alignment of reinforcing fibers by milling creates a significant anisotropy in the composite properties. The degree of fiber alignment is best for glass, carbon, and cellulose fibers. The uniformity of fiber dispersion is again best for glass, carbon, and cellulose fibers. Aramid and nylon fibers tend to clump together and do not disperse easily. Fiber-to-matrix adhesion is a problem. No evidence of consistently good fiber-matrix adhesion is observed except for the precoated cellulose fibers. The interaction between fiber and elastomer can only improve with a coating or sizing that is compatible with both the fiber and its matrix. Adhesion-promoting bonding agents also improve fiber-matrix adhesion. However, each fiber and/or elastomer may be influenced differently by a bonding agent. Adhesion promoters specific to the type of composite being prepared must be sought in order to obtain optimum properties.

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Influence of sinusoidal strain and fiber type to stress and surface temperature of short fiber-rubber composite under dynamic fatigue.

Sen i Gakkaishi ◽

10.2115/fiber.44.12_606 ◽

1988 ◽

Vol 44 (12) ◽

pp. 606-612 ◽

Cited By ~ 2

Author(s):

Satoshi Mashimo ◽

Masayoshi Nakajima ◽

Yoshio Yamaguchi ◽

Michio Ashida

Keyword(s):

Surface Temperature ◽

Fiber Type ◽

Short Fiber ◽

Rubber Composite ◽

Dynamic Fatigue

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Development of Soft Pneumatic Actuators Using High-Strain Elastic Materials with Stress Anisotropy of Short Fibers

Proceedings ◽

10.3390/iecat2020-08526 ◽

2020 ◽

Vol 64 (1) ◽

pp. 41

Author(s):

Akihiro Kojima ◽

Manabu Okui ◽

Taro Nakamura

Keyword(s):

Fiber Type ◽

Artificial Muscle ◽

Axial Direction ◽

Short Fiber ◽

Working Fluid ◽

Artificial Muscles ◽

Rubber Tube ◽

Fiber Reinforced ◽

Soft Robots ◽

Soft Actuators

In recent years, soft robots, such as those with high human affinity and those that excellently imitate the movements of natural creatures, have gained considerable attention. In soft robots, structurally flexible soft actuators need to be used, not conventional motors or hydraulic/pneumatic cylinders. Various types of soft actuators have been developed depending on the driving principle. A pneumatic rubber artificial muscle is a kind of soft actuator that acquires power through injection of a working fluid, such as air, into an elastic structure, such as rubber. In this study, the authors developed an actuator, namely, the straight-fiber-type artificial muscle, which exhibits excellent contraction characteristics. This artificial muscle consists of a rubber tube that contains reinforcing fibers arranged in the axial direction. When air pressure is applied to the rubber tube, the artificial muscle expands only in the radial direction and contracts in the axial direction due to the restraining effect of the reinforcing fiber. While this artificial muscle exhibits excellent contraction properties, it has some drawbacks. One is the difficulty in enclosing the reinforced fibers that have accumulated in the rubber tube, making this artificial muscle difficult to manufacture. In this study, we investigated short-fiber-reinforced artificial muscles that can be easily manufactured. First, a short-fiber-reinforced rubber was prepared, and anisotropy was evaluated via a tensile test. Then, the short-fiber-reinforced artificial muscles were prepared, and their contractions rates were evaluated. The results confirmed that a short-fiber-reinforced rubber can be useful for the manufacture of artificial muscles.

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Biological and Surface Properties of C-Type Virus Particles Produced by Novikoff Ascites Hepatoma Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079395 ◽

1977 ◽

Vol 35 ◽

pp. 388-389

Author(s):

D.C. Hixson ◽

J.C. Chan ◽

J.M. Bowen ◽

E.F. Walborg

Keyword(s):

Surface Properties ◽

Ricinus Communis ◽

Rat Kidney ◽

Leukemia Virus ◽

Viral Envelope ◽

Virus Particles ◽

Chemically Induced ◽

Sarcoma Virus ◽

Hepatocarcinoma Cells ◽

Type C

Several years ago Karasaki (1) reported the production of type C virus particles by Novikoff ascites hepatocarcinoma cells. More recently, Weinstein (2) has reported the presence of type C virus particles in cell cultures derived from transplantable and primary hepatocellular carcinomas. To date, the biological function of these virus and their significance in chemically induced hepatocarcinogenesis are unknown. The present studies were initiated to determine a possible role for type C virus particles in chemically induced hepatocarcinogenesis. This communication describes results of studies on the biological and surface properties of type C virus associated with Novikoff hepatocarcinoma cells.Ecotropic and xenotropic murine leukemia virus (MuLV) activity in ascitic fluid of Novikoff tumor-bearing rats was assayed in murine sarcoma virus transformed S+L- mouse cells and S+L- mink cells, respectively. The presence of sarcoma virus activity was assayed in non-virus-producing normal rat kidney (NRK) cells. Ferritin conjugates of concanavalin A (Fer-Con wheat germ agglutinin (Fer-WGA), and Ricinus communis agglutinins I and II (Fer-RCAI and Fer-RCAII) were used to probe the structure and topography of saccharide determinants present on the viral envelope.

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Recent Studies on a Murine Leukemia Virus Grown in Tissue Culture

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100060544 ◽

1967 ◽

Vol 25 ◽

pp. 106-107

Author(s):

L. Z. de Tkaczevski ◽

E. de Harven ◽

C. Friend

Keyword(s):

Tissue Culture ◽

Solid Tumors ◽

Murine Leukemia Virus ◽

Leukemia Virus ◽

Supernatant Fluid ◽

Virus Particles ◽

Friend Leukemia ◽

Type C ◽

Leukemia Viruses ◽

Murine Leukemia

Despite extensive studies, the correlation between the morphology and pathogenicity of murine leukemia viruses (MLV) has not yet been clarified. The virus particles found in the plasma of leukemic mice belong to 2 distinct groups, 1 or 2% of them being enveloped A particles and the vast majority being of type C. It is generally believed that these 2 types of particles represent different phases in the development of the same virus. Particles of type A have been thought to be an earlier form of type C particles. One of the tissue culture lines established from Friend leukemia solid tumors has provided the material for the present study. The supernatant fluid of the line designated C-1A contains an almost pure population of A particles as illustrated in Figure 1. The ratio is, therefore, the reverse of what is unvariably observed in the plasma of leukemic mice where C particles predominate.

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Structural Organization and Distribution of Fiber Types in Extraocular Muscles of Cats

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100093420 ◽

1972 ◽

Vol 30 ◽

pp. 34-35

Author(s):

Asish C. Nag ◽

Lee D. Peachey

Keyword(s):

Fiber Type ◽

Light And Electron Microscopy ◽

Small Diameter ◽

Extraocular Muscles ◽

Fiber Types ◽

Distinctive Features ◽

Superior Rectus ◽

Adult Cats ◽

Different Diameters ◽

Orbital Region

Cat extraocular muscles consist of two regions: orbital, and global. The orbital region contains predominantly small diameter fibers, while the global region contains a variety of fibers of different diameters. The differences in ultrastructural features among these muscle fibers indicate that the extraocular muscles of cats contain at least five structurally distinguishable types of fibers.Superior rectus muscles were studied by light and electron microscopy, mapping the distribution of each fiber type with its distinctive features. A mixture of 4% paraformaldehyde and 4% glutaraldehyde was perfused through the carotid arteries of anesthetized adult cats and applied locally to exposed superior rectus muscles during the perfusion.

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Spontaneous Production of Type C Virus Particles in a Culture Derived from Rat Embryo Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010009470x ◽

1972 ◽

Vol 30 ◽

pp. 288-289

Author(s):

Elizabeth S. Priori ◽

T. Shigematsu ◽

B. Myers ◽

L. Dmochowski

Keyword(s):

Virus Particle ◽

Mouse Embryo ◽

Calf Serum ◽

Embryo Cell ◽

Virus Particles ◽

Extracellular Virus ◽

Mouse Embryo Cell ◽

Mature Virus Particle ◽

Embryo Cells ◽

Type C

Spontaneous release of type C virus particles in long-term cultures of mouse embryo cells as well as induction of similar particles in mouse embryo cell cultures with IUDR or BUDR have been reported. The presence of type C virus particles in cultures of normal rat embryos has not been reported.NB-1, a culture derived from embryos of a New Zealand Black (NB) rat (rats obtained from Mr. Samuel M. Poiley, N.C.I., Bethesda, Md.) and grown in McCoy's 5A medium supplemented with 20% fetal calf serum was passaged weekly. Extracellular virus particles similar to murine leukemia particles appeared in the 22nd subculture. General appearance of cells in passage 23 is shown in Fig. 1. Two budding figures and one immature type C virus particle may be seen in Fig. 2. The virus particles and budding were present in all further passages examined (currently passage 39). Various stages of budding are shown in Figs. 3a,b,c,d. Appearance of a mature virus particle is shown in Fig. 4.

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