• Title/Summary/Keyword: Carbon fibre

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Carbon Fibre Mesh for the Repair of Abdominal Hernias in Bovines and Caprines: A Review of Nine Clinical Cases

  • Kumar, Naveen;Sharma, A.K.;Maiti, S.K.;Gangwar, A.K.;Kumar, N.
    • Carbon letters
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    • v.8 no.4
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    • pp.269-273
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    • 2007
  • During a 4-year period (2001-2005) 09 animals were surgically treated because of abdominal wall defects (hernia). Out of 9 animals 8 were bovines and one caprine. In each case the defect was repaired with carbon fibre mesh. All the cases were successfully treated and no complication was observed up to six months postoperatively.

A Novel Route to Realise High Degree of Graphitization in Carbon-carbon Composites Derived from Hard Carbons

  • Mathur, R.B.;Bahl, O.P.;Dhami, T.L.;Chauhan, S.K.
    • Carbon letters
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    • v.4 no.3
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    • pp.111-116
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    • 2003
  • Carbon/carbon composites were developed using PAN based carbon fibres and phenolic resin as matrix in different volume fractions and heat treated to temperatures between $1000^{\circ}C$ to $2500^{\circ}C$. Although both the starting precursors are nongraphitizing hard carbons individually, their composites lead to very interesting properties e.g. x-ray diffractograms show the development of graphitic phase for composites having fibre volume fractions of 30~40%. Consequently the electrical resistivity of such composites reaches a value of $0.8\;m{\Omega}cm$, very close to highly graphitic material. However, it was found that by increasing the fibre volume fraction to 50~60%, the trend is reversed. Optical microscopy of the composites also reveals the development of strong columnar type microstructure at the fibre (matrix interface due to stress graphitization of the matrix. The study forcasts a unique possibility of producing high thermal conductivity carbon/carbon composites starting with carbon fibres in the chopped form only.

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Inhomogeneity of Hot Rolling Texture in Cu/Nb Added Ultra Low Carbon Steels

  • Jiang, Ying-Hua;Park, Young-Koo;Lee, Oh-Yeon
    • Korean Journal of Materials Research
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    • v.17 no.12
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    • pp.634-636
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    • 2007
  • The texture and microstructure in Cu/Nb added ultra low carbon steels through the different thickness layer were studied after hot rolling. It was found that the two ultra low carbon steels all show the inhomogeneity of hot rolling texture and the Cu-added ultra low carbon steel was far more inhomogeneous than Nb-added one. In the center layer, the strong ${\alpha}\;fibre,\;{\gamma}\;fibre$ textures and the shear textures including 001<110>, 111<112> were founded. Near the surface, the ${\alpha}\;fibre$ texture and the orientation texture caused by a typical plane-strain deformation condition of bcc metals were observed.

Experimental and microstructural evaluation on mechanical properties of sisal fibre reinforced bio-composites

  • Kumar, B. Ravi;Hariharan, S.S.
    • Steel and Composite Structures
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    • v.33 no.2
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    • pp.299-306
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    • 2019
  • The natural fibre composites are termed as bio-composites. They have shown a promising replacement to the current carbon/glass fibre reinforced composites as environmental friendly materials in specific applications. Natural fibre reinforced composites are potential materials for various engineering applications in automobile, railways, building and Aerospace industry. The natural fibre selected to fabricate the composite material is plant-based fibre e.g., sisal fibre. Sisal fibre is a suitable reinforcement for use in composites on account of its low density, high specific strength, and high hardness. Epoxy is a thermosetting polymer which is used as a resin in natural fibre reinforced composites. Hand lay-up technique was used to fabricate the composites by reinforcing sisal fibres into the epoxy matrix. Composites were prepared with the unidirectional alignment of sisal fibres. Test specimens with different fibre orientations were prepared. The fabricated composites were tested for mechanical properties. Impact test, tensile test, flexural test, hardness test, compression test, and thermal test of composites had been conducted to assess its suitability in industrial applications. Scanning electron microscopy (SEM) test revealed the microstructural information of the fractured surface of composites.

Interface and Microstructure Development in Carbon/Carbon Composites

  • Mathur, R.B.;Bahl, O.P.;Dhami, T.L.;Chauhan, S.K.;Dhakate, S.R.;Rand, B.
    • Carbon letters
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    • v.5 no.2
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    • pp.62-67
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    • 2004
  • Performance of carbon-carbon composites is known to be influenced by the fibre matrix interactions. The present investigation was undertaken to ascertain the development of microstructure in such composites when carbon fibres possessing different surface energies (T-300, HM-35, P120 and Dialed 1370) and pitch matrices with different characteristics (Coal tar pitch $SP110^{\circ}C$ and mesophase pitch $SP285^{\circ}C$) are used as precursor materials. These composites were subjected to two different heat treatment temperatures of $1000^{\circ}C$ and $2600^{\circ}C$. Quite interesting changes in the crystalline parameters as well as the matrix microstructure are observed and attempt has been made to correlate these observations with the fibre matrix interactions.

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Chromate Removal from Wastewater using Micellar Enhanced Ultrafiltration and Activated Carbon Fibre Processes; Validation of Experiment with Mathematical Equations

  • Bade, Rabindra;Lee, Seung-Hwan
    • Environmental Engineering Research
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    • v.13 no.2
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    • pp.98-104
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    • 2008
  • In this study, chromate and cetylperidinium chloride (CPC) removal from artificial wastewater was monitored by using micellar enhanced ultrafiltration (MEUF) and activated carbon fibre (ACF) adsorption hybrid processes. For the efficient chromate removal, molar concentration of the CPC should be five times that of chromate and it should be at least one critical micelle concentration (CMC). The MEUF was found to be effective in the chromate removal while ACF in the CPC adsorption to produce chromate and CPC free effluents. The chromate and CPC removal was 99.8% from MEUF-ACF process. Effluent chromate concentration was exponentially correlated with molar ratio of CPC to chromate and pH.

Novel Flexible Supercapacitors Fabricated by Simple Integration of Electrodes, Binders, and Electrolytes into Glass Fibre Separators

  • Yoo, Joung Eun;Bae, Joonho
    • Journal of the Korean Electrochemical Society
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    • v.17 no.4
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    • pp.237-244
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    • 2014
  • We report novel and simple structure of supercapacitors fabricated by using flexible glass fibre separators as templates. This method does not require separate electrodes, binders and high pressure/temperature to build the supercapacitor unit cells as required by the conventional technology. The supercapacitors were fabricated by drop-casting solution mixtures of carbonaceous active materials/gel electrolytes onto two sides of glass fibre separators. Two carbonaceous materials (nanoscaled activated carbons, multi-walled carbon nanotubes) were investigated as electrode materials. The electrochemical measurements reveal that the separatorbased supercapacitors using ACs successfully demonstrated significant mass specific capacitance ($22.3F\;g^{-1}$) and energy density ($9.7Wh\;kg^{-1}$), indicating this method can be useful in fabricating flexible, wearable and stretchable energy storage devices in more straightforward and cost-effective way than current technology.

Operational behaviour and reliability measures of a viscose staple fibre plant including deliberate failures

  • Sengar, Surabhi;Singh, S.B.
    • International Journal of Reliability and Applications
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    • v.13 no.1
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    • pp.1-17
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    • 2012
  • This Paper deals with the stochastic behavior and failure analysis of a Viscose Staple Fibre Plant which produces fibre for making clothes. The fibre making plant is a complex system with various subsystems as: Vendor (supplies Charcoal and Sulphur, raw materials for the process), Carbon di sulphide Plant, Acid Plant, Pulp Plant and Processing Plant. The considered system can completely fail due to failure of any of the subsystems. The Carbon di Sulphide Plant can fail in two different ways, due to lack of Sulphur or Charcoal. Processing Plant has the configuration 5-out-of-10: d and 6-out-of-10: f. It is also assumed that the system can fail due to workers strike and catastrophic failure. All failures follow exponential time distribution whereas all repairs follow general time distribution. Preventive Maintenance policy has been applied to reduce the failure in the system. Various reliability characteristics such as transition state probabilities, steady state behavior, reliability, availability, M.T.T.F and the cost analysis have been obtained using supplementary variable technique and Gumbel-Hougaard copula methodology.

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Mechanical properties of steel-CFRP composite specimen under uniaxial tension

  • Uriayer, Faris A.;Alam, Mehtab
    • Steel and Composite Structures
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    • v.15 no.6
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    • pp.659-677
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    • 2013
  • This paper introduces new specimens of Steel-Carbon Fibre Reinforced Polymer composite developed in accordance with standard test method and definition for mechanical testing of steel (ASTM-A370). The main purpose of this research is to study the behaviour of steel-CFRP composite specimen under uniaxial tension to use it in beams in lieu of traditional steel bar reinforcement. Eighteen specimens were prepared and divided into six groups, depending upon the number of the layers of CFRP. Uniaxial tensile tests were conducted to determine yield strength and ultimate strength of specimens. Test results showed that the stress-strain curve of the composite specimen was bilinear prior to the fracture of CFRP laminate. The tested composite specimens displayed a large difference in strength with remarkable ductility. The ultimate load for Steel-Carbon Fibre Reinforced Polymer composite specimens was found using the model proposed by Wu et al. (2010) and nonlinear FE analysis. The ultimate loads obtained from FE analysis are found to be in good agreement with experimental ones. However, ultimate loads obtained applying Wu model are significantly different from experimental/FE ones. This suggested modification of Wu model. Modified Wu's model which gives a better estimate for the ultimate load of Steel-Carbon Fibre Reinforced Polymer (SCFRP) composite specimen is presented in this paper.

Relationship between the structure and composition of rumen microorganisms and the digestibility of neutral detergent fibre in goats

  • Liu, Kaizhen;Wang, Lizhi;Yan, Tianhai;Wang, Zhisheng;Xue, Bai;Peng, Quanhui
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.1
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    • pp.82-91
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    • 2019
  • Objective: This experiment was conducted to compare the structure and composition of ruminal microorganisms in goats with high and low neutral detergent fibre (NDF) digestibility. Methods: Nineteen crossbred goats were used as experimental animals and fed the same total mixed rations during the 30-day pre-treatment and 6-day digestion trialperiods. All faeces were collected during the digestion period for measuring the NDF digestibility. Then, high and the low NDF digestibility individuals were chosen for the high NDF digestibility group (HFD) and low NDF digestibility group (LFD), respectively. Rumen contents were collected for total microbial DNA extraction. The V4 region of the bacterial 16S rRNA gene was amplified using universal primers of bacteria and sequenced using high-throughput sequencer. The sequences were mainly analysed by QIIME 1.8.0. Results: A total of 18,694 operational taxonomic units were obtained, within 81.98% belonged to bacteria, 6.64% belonged to archaea and 11.38% was unassigned microorganisms. Bacteroidetes, Firmicutes, and Proteobacteria were the predominant microbial phyla in both groups. At the genus level, the relative abundance of fifteen microorganisms were significantly higher (p<0.05) and six microorganisms were extremely significantly higher (p<0.01) in LFD than HFD. Overall, 176 core shared genera were identified in the two groups. The relative abundance of 2 phyla, 5 classes, 10 orders, 13 families and 15 genera had a negative correlation with NDF digestibility, but only the relative abundance of Pyramidobacter had a positive correlation with NDF digestibility. Conclusion: There were substantial differences in NDF digestibility among the individual goats, and the NDF digestibility had significant correlation with the relative abundance of some ruminal microorganisms.