Seyed Hamidreza Ghaffar

Bio: Seyed Hamidreza Ghaffar is an academic researcher from Brunel University London. The author has contributed to research in topics: Materials science & Compressive strength. The author has an hindex of 16, co-authored 39 publications receiving 1002 citations.

Structural analysis for lignin characteristics in biomass straw

Abstract: Agricultural by-products are the most promising feedstock for the generation of renewable, carbon neutral substitutes for synthetic materials (e.g. biofuel, building materials). The demand for efficient utilisation of lignin biomass has induced detailed analyses of its fundamental chemical structures and development of analysing technologies. This paper reviews the structural analysis techniques for straw lignin together with the morphology of the lignin biomass and the study of the form and structure of organisms and their specific structural features. The review showed that the studies on lignin could be divided into the qualitative and quantitative analyses; different analytical methods could provide significantly different results that are even sometimes not directly comparable. Among many techniques reviewed, the magnetic resonance techniques have proved to be efficient analytical tools for the structural elucidation of these complex biopolymers. Quantitative and qualitative structural analysis of lignin indicated a great potential for industrial crops optimisation due to in-depth microstructure interpretation, and detailed and accurate chemical composition although the composition and structure of straw lignin have been discovered highly complex and varied considerably within and among plants. The structure of lignin has remained one of the most difficult biopolymers to characterise, however recent advances in analytical chemistry and spectroscopy have dramatically improved the understanding of this natural resource, and further value added utilisations are being expected for the lignin and its related biomass.

American Society for Testing and Materials

Abstract: The American Society for Testing and Materials (ASTM) is an independent organization devoted to the development of standards.

Paving the Way for Lignin Valorisation: Recent Advances in Bioengineering, Biorefining and Catalysis.

Abstract: Lignin is an abundant biopolymer with a high carbon content and high aromaticity. Despite its potential as a raw material for the fuel and chemical industries, lignin remains the most poorly utilised of the lignocellulosic biopolymers. Effective valorisation of lignin requires careful fine-tuning of multiple "upstream" (i.e., lignin bioengineering, lignin isolation and "early-stage catalytic conversion of lignin") and "downstream" (i.e., lignin depolymerisation and upgrading) process stages, demanding input and understanding from a broad array of scientific disciplines. This review provides a "beginning-to-end" analysis of the recent advances reported in lignin valorisation. Particular emphasis is placed on the improved understanding of lignin's biosynthesis and structure, differences in structure and chemical bonding between native and technical lignins, emerging catalytic valorisation strategies, and the relationships between lignin structure and catalyst performance.

Progress Report on Natural Fiber Reinforced Composites

Abstract: This century has witnessed remarkable achievements in green technology in material science through the development of natural fiber reinforced composites. The development of high-performance engineering products made from natural resources is increasing worldwide day by day. There is increasing interest in materials demonstrating efficient use of renewable resources. Nowadays, more than ever, companies are faced with opportunities and choices in material innovations. Due to the challenges of petroleum-based products and the need to find renewable solutions, more and more companies are looking at natural fiber composite materials. The primary driving forces for new bio-composite materials are the cost of natural fibers (currently priced at one-third of the cost of glass fiber or less), weight reduction (these fibers are half the weight of glass fiber), recycling (natural fiber composites are easier to recycle) and the desire for green products. This Review provides an overview of natural fiber reinfocred composites focusing on natural fiber types and sources, processing methods, modification of fibers, matrices (petrochemical and renewable), and their mechanical performance. It also focuses on future research, recent developments and applications and concludes with key issues that need to be resolved. This article critically summarizes the essential findings of the mostly readily utilized reinforced natural fibers in polymeric composite materials and their performance from 2000 to 2013.