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Tehran, Iran

Iranian Research Organization for Science and Technology is a comprehensive science policy research center directly attached to the Ministry of Science, Research and Technology of Iran which was approved and ratified by Revolutionary Council of Iran in 1980. IROST as the biggest research center in Iran, is chiefly engaged in development of strategies, policies, R&D systems, management, foresight and evaluation of related Science and Technology development and S&T for economic progress.IROST has made great advances in providing alternative sources of energy, namely solar energy, biodiesel from microalgae and bi-ethanol from agricultural waste. IROST has also made progress in pharmacological fields.IROST undertakes commissioned research with International Organizations such as, United Nations Educational, Scientific and Cultural Organization World Intellectual Property Organization United Nations Development Programme Organisation of Islamic Conference Standing Committee on Scientific & Technological Cooperation Commission on Science and Technology for Sustainable Development in the South Third World Academy of Science Islamic Educational, Scientific and Cultural Organization International Federation of Inventors' Associations Asian Pacific Center for Transfer of Technology Indian Ocean Rim Association for Regional Cooperation ↑ Wikipedia.


Ashori A.,Iranian Research Organization for Science and Technology
Journal of Polymers and the Environment | Year: 2010

Hybrid composites of thermoplastic biofiber reinforced with waste newspaper fiber (NF) and poplar wood flour (WF) were prepared. The weight ratio of the lignocellulosic materials to polymer was 30:70 (w:w). Polypropylene (PP) and maleic anhydride grafted polypropylene (MAPP) were also used as the polymer matrix and coupling agent, respectively. The mechanical properties, morphology and thermal properties were investigated. The obtained results showed that tensile and flexural modulus of the composites were significantly enhanced with addition of biofibers in both types (fiber and flour), as compared with pure PP. However, the increasing in WF content substantially reduced the tensile, flexural and impact modulus, but improved the thermal stability. This effect is explained by variations in fiber morphological properties and thermal degradation. Increasing fiber aspect ratio improved mechanical properties. The effect of fiber size on impact was minimal compared to the effects of fiber content. Scanning electron microscopy has shown that the composite, with coupling agent, promotes better fiber-matrix interaction. The largest improvement on the thermal stability of hybrid composites was achieved when WF was added more. In all cases, the degradation temperatures shifted to higher values after addition of MAPP. This work clearly showed that biofiber materials in both forms of fiber and flour could be effectively used as reinforcing elements in thermoplastic PP matrix. © 2009 Springer Science+Business Media, LLC. Source


Ashori A.,Iranian Research Organization for Science and Technology
Polymer Engineering and Science | Year: 2014

The objective of this study was to prepare chitosan and starch composite films by the addition of 0-3 wt% graphene nanosheets. The film's tensile strength (TS), tensile modulus (TM), elongation at break (E), moisture uptake (Mu), and water vapor transmission rate (WVTR) were investigated. The surface morphology of the composite films was studied using scanning electron microscopy (SEM). Regardless of biopolymer type, both the TS and TM of the composite films first increased and then decreased with graphene loading. Composite film made with native (unmodified) starch showed lower TS and TM than those with chitosan. Composite films exhibit lower E values than pure chitosan and starch; this is attributed to the increase in the hardness of the films. SEM micrographs indicated that, the surface roughness and phase separation increased with increasing graphene content. This is due to the aggregation of graphene nanosheets, leading to the reduced compatibility of biopolymers. The addition of graphene considerably decreased WVTR and Mu of the composite films. These results indicated that graphene is a promising reinforcing agent for biopolymer composite films. © 2013 Society of Plastics Engineers. Source


Ashori A.,Iranian Research Organization for Science and Technology | Sheshmani S.,Islamic Azad University at Tehran
Bioresource Technology | Year: 2010

In this research, hybrid composite materials were made from the combination of recycled newspaper fiber (RNF) and poplar wood flour (PWF) as reinforcement, recycled polypropylene (RPP) as polymer matrix, and maleated polypropylene (MAPP) as coupling agent, by using injection molding. The effects of weight fractions of fibers and coupling agent concentration on the physical properties of the composites in terms of water absorption and thickness were studied. Composites containing more fraction of RNF exhibited maximum water absorption during the whole duration of immersion. This effect can be explained by the presence of a high amount of holocellulose present in the RNF, compared to the PWF. The addition of MAPP exhibited a beneficial effect on both the water absorption and thickness swelling by improving the quality of adhesion between polymer and fibers. © 2010 Elsevier Ltd. All rights reserved. Source


Nourbakhsh A.,Iranian Research Institute of Forests and Rangelands | Ashori A.,Iranian Research Organization for Science and Technology
Bioresource Technology | Year: 2010

This article presents the application of agro-waste materials (i.e., corn stalk, reed stalk, and oilseed stalk) in order to evaluate and compare their suitability as reinforcement for thermoplastics as an alternative to wood fibers. The effects of fiber loading and CaCO3 content on the mechanical properties were also stud- ied. Overall trend shows that with addition of agro-waste materials, tensile and flexural properties of the composites are significantly enhanced. Oilseed fibers showed superior mechanical properties due to their high aspect ratio and chemical characteristics. The order of increment in the mechanical properties of the composites is oilseed stalk > corn stalk > reed stalk at all fiber loadings. The tensile and flexural proper- ties of the composite significantly decreased with increasing CaCO3 content, due to the reduction of interface bond between the fiber and matrix. It can be concluded from this study that the used agro-waste materials are attractive reinforcements from the standpoint of their mechanical properties. © 2009 Elsevier Ltd. All rights reserved. Source


Ashori A.,Iranian Research Organization for Science and Technology | Nourbakhsh A.,Iranian Research Institute of Forests and Rangelands
Bioresource Technology | Year: 2010

In this work, the effects of wood species, particle sizes and hot-water treatment on some physical and mechanical properties of wood-plastic composites were studied. Composites of thermoplastic reinforced with oak (Quercus castaneifolia) and pine (Pinus eldarica) wood were prepared. Polypropylene (PP) and maleic anhydride grafted polypropylene (MAPP) were used as the polymer matrix and coupling agent, respectively. The results showed that pine fiber had significant effect on the mechanical properties considered in this study. This effect is explained by the higher fiber length and aspect ratio of pine compared to the oak fiber. The hot-water treated (extractive-free) samples, in both wood species, improved the tensile, flexural and impact properties, but increased the water absorption for 24 h. This work clearly showed that lignocellulosic materials in both forms of fiber and flour could be effectively used as reinforcing elements in PP matrix. Furthermore, extractives have marked effects on the mechanical and physical properties. © 2009 Elsevier Ltd. All rights reserved. Source

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