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Effect of Cation Distribution and Structural Properties on Permeability of Ni-Mg Ferrite with Li2CO3 Additive
Mohammad Rabiul Hassan,
Mohammad Torikul Islam,
Mohammad Belal Hossain,
Sumi Umme Honney,
Mohammed Nazrul Islam Khan
Issue:
Volume 3, Issue 1, June 2019
Pages:
1-8
Received:
29 November 2018
Accepted:
16 January 2019
Published:
31 January 2019
DOI:
10.11648/j.cm.20190301.11
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Abstract: The structural properties and permeability of polycrystalline Ni0.6Mg0.4Fe2O4 ferrite are studied with the addition of Li2CO3 at 0%, 2%, 4%, and 6%. The samples were synthesized by the conventional ceramic method at 1300C sintering temperature for 6 hours. X-ray diffraction method is applied to understand the crystal structure of the following ferrite and it is confirmed that the samples have absolute single phase cubic spinel structure. The lattice constant of the ferrite varies with the increasing of Li2CO3 content. The microstructure analysis of the samples is carried out by SEM micrographs. From SEM images it is observed that the ferrite is in regular in shape and the grains are well connected with each other. The average grain sizes of the sample increased with increasing Li2CO3 content. Crystalline size of the sample follows the same manner of grain size of the samples. The Curie temperature is measured by using inductance analyzer. Curie temperature increased at 2% addition of Li2CO3 and the further increase in Li2CO3 leads to decrease in the Curie temperature whereas permeability shows just opposite attitude of Curie temperature in this study. Complex permeability and relative quality factor are also measured as a function of temperature and frequency respectively.
Abstract: The structural properties and permeability of polycrystalline Ni0.6Mg0.4Fe2O4 ferrite are studied with the addition of Li2CO3 at 0%, 2%, 4%, and 6%. The samples were synthesized by the conventional ceramic method at 1300C sintering temperature for 6 hours. X-ray diffraction method is applied to understand the crystal structure of the following fer...
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Numerical Simulation of Flow Processes in Extrusion Tools for Partly Crosslinked and Highly Filled Plastic Melts
Kalman Geiger,
Gerhard Alfred Martin,
Andreas Sobotta
Issue:
Volume 3, Issue 1, June 2019
Pages:
9-21
Received:
22 October 2018
Accepted:
1 February 2019
Published:
28 February 2019
DOI:
10.11648/j.cm.20190301.12
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Abstract: The complex flow behaviour of partly crosslinked or highly filled polymer melts will be described with a new heuristic flow law, which takes into account the pseudoplastic flow behaviour in the regime of the viscosity curve for low and for high shear rates. The CARPOW law is a combination of the often used power and Carreau law. It describes the flow behaviour of partly crosslinked or highly filled polymer melts for the shear rate ranges in extrusion and injection molding tools. The evaluation and the presentation of the rotational and the capillary rheometrical viscosity measurements are detailed described. For highly filled or for partly crosslinked plastic melts a new defined consistency parameter is defined. It characterizes the flow obstruction in the CARPOW law. Further the temperature invariant representation of the CARPOW law is shown. This new flow law is applied for a partly crosslinked and a highly filled polymer system. The design of the extrusion tools should consider the flow behaviour described by the CARPOW law. Only with this flow law the design of tooling in the case of partly crosslinked or highly filled polymer melts is correct. Two praxis relevant examples demonstrate the calculation for an extrusion die using this new flow law.
Abstract: The complex flow behaviour of partly crosslinked or highly filled polymer melts will be described with a new heuristic flow law, which takes into account the pseudoplastic flow behaviour in the regime of the viscosity curve for low and for high shear rates. The CARPOW law is a combination of the often used power and Carreau law. It describes the fl...
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Development and Characterization (Thermo-Mechanical and Morphological) of Completely Biodegradable Composites of Polypropylene (PP) Reinforced Short Natural Fiber Jute
Md. Nazrul Islam,
M. A. Gafur,
Md. Sahadat Hossain
Issue:
Volume 3, Issue 1, June 2019
Pages:
22-29
Received:
17 October 2018
Accepted:
9 November 2018
Published:
12 April 2019
DOI:
10.11648/j.cm.20190301.13
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Abstract: The composites of biodegradable Polypropylene (PP) reinforced with short jute fiber were prepared by melt mixing followed by hot press molding. The composites were prepared with the aim to develop new biodegradable materials for different applications. Jute fiber is well known for its biodegradable properties but PP is not biodegradable material. The combination of the two materials will lead to the biodegradable properties in some extent as well as higher mechanical properties. The mechanical properties, thermal properties, micro structural analysis and morphologies of the composites were studied via UTM (Universal Testing Machine), Thermo gravimetric analysis (TGA) and Scanning electron microscopy (SEM) respectively. The mechanical properties like tensile strength (TS), tensile modulus (TM), flexural strengths (FS) and flexural modulus (FM) were measured for both treated and untreated specimens and compared. The results show that alkali treated jute reinforced composites have much better properties than the untreated one. The TS, TM, FS and FMwere decreased with increasing of untreated fiber and increased with the increasing of treated fiber in PP-Jute composites (PPJC). The changes in the mechanical properties were broadly related to the accompanying modifications and interfacial bonding of PPJC. Scanning Electron Microscopic image observations indicated good interfacial contact between the short jute fiber and PP matrix. Thermal analysis (TG /DTG) revealed that the introduction of short jute fiber led to a slightly improved thermo oxidative stability of PP-Jute composites.
Abstract: The composites of biodegradable Polypropylene (PP) reinforced with short jute fiber were prepared by melt mixing followed by hot press molding. The composites were prepared with the aim to develop new biodegradable materials for different applications. Jute fiber is well known for its biodegradable properties but PP is not biodegradable material. T...
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Biosynthesis, Characterization and Photocatalytic Activity of Copper/Copper Oxide Nanoparticles Produced Using Aqueous Extract of Lemongrass Leaf
Issue:
Volume 3, Issue 1, June 2019
Pages:
30-35
Received:
4 December 2018
Accepted:
30 January 2019
Published:
12 April 2019
DOI:
10.11648/j.cm.20190301.14
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Abstract: The paper presents a green, simple and eco-friendly method to synthesize copper/copper oxide nanoparticles (Cu/CuO-NPs) from CuSO4 solution using aqueous extract of lemongrass leaf as the reducing and capping agent. The influence of some factors such as the volume ratio of lemongrass leaf extract and CuSO4 solution, pH and temperature to the synthesis of Cu/CuO-NPs were investigated. The results showed that the formation of stable Cu/CuO-NPs was rapid. CuSO4 solution changed from light blue to yellowish green colour after adding aqueous extract of lemongrass leaf. The formation of Cu/CuO-NPs was confirmed by UV-Vis spectroscopy. In this research, transmission electron microscopy (TEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD) techniques were used to determine the morphology and crystalline phase of Cu/CuO-NPs. The obtained Cu/CuO-NPs were spherical, with the size ranging from 5.67 to 9.10 nm. The photocatalytic activity of the synthesized Cu/CuO-NPs was examined via degradation process of methylene blue under sunlight irradiation.
Abstract: The paper presents a green, simple and eco-friendly method to synthesize copper/copper oxide nanoparticles (Cu/CuO-NPs) from CuSO4 solution using aqueous extract of lemongrass leaf as the reducing and capping agent. The influence of some factors such as the volume ratio of lemongrass leaf extract and CuSO4 solution, pH and temperature to the synthe...
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