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Nitrate Removal from Groundwater Using Sodium Alginate Doped with Nano-Hydroxyapatite
Salah Abo-El-Enein,
Yahia Gedamy,
Amr Ecresh
Issue:
Volume 6, Issue 6, December 2017
Pages:
102-114
Received:
16 March 2017
Accepted:
12 April 2017
Published:
26 October 2017
Abstract: In the present work, the hydroxyapatite/alginate nano-composite adsorbent was prepared by incorporating nano-sized hydroxyapatite (nHAp) into alginate polymer and uses this adsorbent for removal of nitrate from groundwater. The synthesized nano-composite and pure alginate as well as the pure hydroxyapatite were characterized with Fourier Transform Infrared (FT-IR) spectroscopy to ascertain the functional groups. The adsorption characteristics of nitrate from groundwater on the HAp/Alg nano-composite were optimized under different operational parameters like contact time, pH, adsorbent dosage, initial concentration of nitrate and temperature in batch system. Maximum equilibrium capacity reached 99% of nitrate removal by using the HAp/Alg nano-composite after 240min at pH 3; adsorbent dosage, 2g; initial concentration, 100mg/l and temperature, 20°C. The kinetics studies revealed that the pseudo-second-order kinetic model was able to describe the dynamic behavior of the adsorption process by composite adsorbents used in this work. Also, the Langmuir isotherm model is very well fitted to the equilibrium data. The mechanism of NO3- ions adsorption by the nano-composite adsorbent was described. So, it is concluded that HAp/Alg nano-composite is a relatively efficient and low cost as well as the results validated the feasibility of HAp/Alg nano-composite for highly effective removal of nitrate from an aqueous solution.
Abstract: In the present work, the hydroxyapatite/alginate nano-composite adsorbent was prepared by incorporating nano-sized hydroxyapatite (nHAp) into alginate polymer and uses this adsorbent for removal of nitrate from groundwater. The synthesized nano-composite and pure alginate as well as the pure hydroxyapatite were characterized with Fourier Transform ...
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Obtaining a Gypsum-Cement Blend, to Be Used as Filling, with Low Hardening Temperature
Gabriela Abad-Farfán,
Tito Fernando Muñoz-Cuenca,
Paúl Bolivar Torres-Jara,
Efrén Vázquez-Silva
Issue:
Volume 6, Issue 6, December 2017
Pages:
115-121
Received:
7 September 2017
Accepted:
26 September 2017
Published:
7 November 2017
Abstract: When a beam, made of material whose properties would be affected at temperatures above 37°C and with irregular geometry at its ends, is subjected to a bending test; it is necessary to guarantee the stability of its support points to achieve success in the execution of the test. This paper presents a study on the properties of a particular composite material that is used as a filling for certain hollow supports with the aim to provide stability to the ends of the beam when the load is applied. Although the mixture employed reacts exothermically, it does not exceed the maximum temperature level above which the mechanical properties of the constituent material of the beam would be affected. In addition, the strength of the mixture is such that it is able to withstand the compression stresses that are generated during the test.
Abstract: When a beam, made of material whose properties would be affected at temperatures above 37°C and with irregular geometry at its ends, is subjected to a bending test; it is necessary to guarantee the stability of its support points to achieve success in the execution of the test. This paper presents a study on the properties of a particular composite...
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Experimental Investigation on the Properties of Compressed Earth Blocks Stabilised with a Liquid Chemical
Issue:
Volume 6, Issue 6, December 2017
Pages:
122-128
Received:
28 September 2017
Accepted:
10 October 2017
Published:
7 November 2017
Abstract: Soil blocks are usually stabilised with cementing materials, fibres or chemicals to improve their performance properties for construction purpose. This study investigates the properties of compressed earth blocks stabilised with a liquid chemical (Pidiproof LW+). Experiment was conducted using 0.5, 1 and 1.5% weight contents of Pidiproof LW+ to produce compressed earth blocks and cured at 7, 14, 21 and 28 days. The blocks were tested for density, absorption coefficient, compressive strength and splitting tensile strength. It was found that with the exception of density test, the chemical inclusion in the other tests significantly improved the performance properties of the compressed earth blocks. Furthermore, the higher chemical content (1.5%) inclusion in the compressed earth block provided better performance properties. The paper concludes that the inclusion of the liquid chemical in the compressed earth blocks generally improved the performance properties of the blocks. Recommendation is made to the use of other chemicals for applicability in earthen construction.
Abstract: Soil blocks are usually stabilised with cementing materials, fibres or chemicals to improve their performance properties for construction purpose. This study investigates the properties of compressed earth blocks stabilised with a liquid chemical (Pidiproof LW+). Experiment was conducted using 0.5, 1 and 1.5% weight contents of Pidiproof LW+ to pro...
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Recent Advances in Carbon Nanotube-Polymer Composites
Issue:
Volume 6, Issue 6, December 2017
Pages:
129-148
Received:
24 September 2017
Accepted:
24 October 2017
Published:
24 November 2017
Abstract: Carbon nanotubes demonstrate remarkable mechanical, thermal, and electrical properties, which allow a number of exciting potential applications. In this article, the most recent progress in research on the development of carbon nanotube-polymer composites is critically reviewed, with emphasis on recent advances in the principles and techniques for carbon nanotube functionalization. Various functionalization approaches and their role in the preparation of carbon nanotube-polymer composites with improved mechanical and electrical properties are discussed. The interaction between carbon nanotubes and polymers is also reviewed. Various techniques of carbon nanotube-polymer interaction measurements, including experimental and modelling studies, are described. Different methods of interaction improvement, mainly categorized under covalent and noncovalent interactions, are also described afterwards. An optimum carbon nanotube-polymer interaction is a crucial factor towards reaching the full potential of carbon nanotubes in nanocomposites. Potential topics of oncoming focus along with the potential applications of carbon nanotube-polymer composites are highlighted.
Abstract: Carbon nanotubes demonstrate remarkable mechanical, thermal, and electrical properties, which allow a number of exciting potential applications. In this article, the most recent progress in research on the development of carbon nanotube-polymer composites is critically reviewed, with emphasis on recent advances in the principles and techniques for ...
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Evaluation of Tensile Strength of Jute Fiber Reinforced Polypropylene Composite
Issue:
Volume 6, Issue 6, December 2017
Pages:
149-153
Received:
9 October 2017
Accepted:
24 October 2017
Published:
24 November 2017
Abstract: Natural fiber (such as flax, hemp, jute, kenaf, etc.) reinforced polymer resin composites are biodegradable composites as they are using fibers from renewable sources. It is also better than synthetic fibers (such as glass, carbon, ceramic fibers, etc.) in a sense of environmental cause. In this research work, jute fiber reinforced polypropylene matrix composites have been developed using hot compression molding technique. Various process parameters are used such as fiber condition (untreated and alkali treated), fiber sizes (1, 2 and 4 mm) and percentages (5%, 10% and 15% by weight) in this research work. Tensile test and optical microscopy are used for characterization. Effect of tensile strength has a linear relation with fiber size and fiber percentage but after a certain size and percentage, the tensile strength shows an inverse relation with the fiber length and fiber percentage. There is no significant change has been observed for treated and untreated jute fiber reinforcement.
Abstract: Natural fiber (such as flax, hemp, jute, kenaf, etc.) reinforced polymer resin composites are biodegradable composites as they are using fibers from renewable sources. It is also better than synthetic fibers (such as glass, carbon, ceramic fibers, etc.) in a sense of environmental cause. In this research work, jute fiber reinforced polypropylene ma...
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Application of Plasma Erosion Technique for Faster Degradation of Coatings and Prediction of Their Durability
Issue:
Volume 6, Issue 6, December 2017
Pages:
154-158
Received:
8 March 2017
Accepted:
8 April 2017
Published:
29 November 2017
Abstract: Assessment of durability of coatings is crucial for researcher especially for design of paints which would have service life warranty. As natural exposure takes several months for such studies, there is tendency today to use faster techniques like UV testers and Xenon arc weatherometers. Although these techniques are several times faster than natural exposure, it takes few weeks for coating chemist to observe any degradation. Among quicker techniques, plasma erosion is found to be useful one. Oxygen plasma produces extremely rapid degradation and few hours of exposure to plasma provides effects of several years of natural weathering. Advantages of the technique are speed and plasma equipments are cheaper than weatherometer. Results obtained with plasma erosion technique are found to have good correlation with results of exposure under Xenon arc source.
Abstract: Assessment of durability of coatings is crucial for researcher especially for design of paints which would have service life warranty. As natural exposure takes several months for such studies, there is tendency today to use faster techniques like UV testers and Xenon arc weatherometers. Although these techniques are several times faster than natur...
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Effect of Rice Husks Concrete Preformed Coffers and Bricks Use on Building Structural Elements
Yawovi Mawuénya Xolali Dany Ayité,
Irina Pachoukova,
Koffi-Sa Bédja
Issue:
Volume 6, Issue 6, December 2017
Pages:
159-164
Received:
4 November 2017
Accepted:
16 November 2017
Published:
27 December 2017
Abstract: This article highlights the effect of rice husks concrete preformed coffers and bricks use on building structural elements (joists, beams, columns and footings). For this purpose, 15 cm thick of preformed coffers, hollow and solid bricks are made from cement - rice husks, cement - rice husks - sand and sand –cement mixtures to determine their characteristics: density, surface weight, brick compressive strength and preformed coffer bending strength. These characteristics were used to calculate building structural elements (joist, beam, column and footing). The results show that the preformed coffers and bricks of rice husks concrete are lighter than those made of sand - cement mortar. The compressive or bending strengths of these elements are similar. The use of rice husks concrete preformed coffers reduces dimensions and reinforcing steels of building structural elements.
Abstract: This article highlights the effect of rice husks concrete preformed coffers and bricks use on building structural elements (joists, beams, columns and footings). For this purpose, 15 cm thick of preformed coffers, hollow and solid bricks are made from cement - rice husks, cement - rice husks - sand and sand –cement mixtures to determine their chara...
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