Home / Advanced Search

  • Title/Keywords

  • Author/Affliations

  • Journal

  • Article Type

  • Start Year

  • End Year

Update SearchingClear
  • Articles
  • Online
Search Results (190)
  • Open Access

    ARTICLE

    The Effects of Gamma Irradiation on Molecular Weight, Morphology and Physical Properties of PHBV/Cloisite 30B Bionanocomposites

    Kahina Iggui1,2,*, Mustapha Kaci1, Mohamed Mahlous3, Nicolas Le Moigne4, Anne Bergeret4

    Journal of Renewable Materials, Vol.7, No.9, pp. 807-820, 2019, DOI:10.32604/jrm.2019.06778

    Abstract In this paper, the effects of gamma irradiation on Cast poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and PHBV/Cloisite 30B (C30B) (3 wt%) bionanocomposite prepared by melt compounding, were evaluated at various doses, i.e., 5, 15, 20, 50 and 100 kGy at room temperature in air. Changes in molecular weight, morphology and physical properties were investigated. The study showed that the main degradation mechanism occurring in gamma irradiation in both Cast PHBV and C-PHBV/3C30B bionanocomposite is chain scission, responsible for the decrease of molecular weight. Differential scanning calorimetry (DSC) data indicated a regular decrease in crystallization temperature, melting temperature and crystallinity index for all irradiated… More >

  • Open Access

    ARTICLE

    Synthesis of a Fully Biobased Polyfunctional Vinyl Oligomer and Their UV Cured Films Prepared via Thiol-ene Coupling

    Changqing Fu1,2, Jiahui Wang1,2, Lie Chen1,2, Liang Shen1,2,*

    Journal of Renewable Materials, Vol.7, No.8, pp. 795-805, 2019, DOI:10.32604/jrm.2019.07503

    Abstract In this paper, a fully bio-based vinyl oligomer with high functionalities was successfully prepared from rapeseed oil by three modification steps: epoxidation of rapeseed oil, solvent-free and catalyst-free ring opening by 10-undecylenic acid followed by esterification with 10-undecenoyl chloride. Then, the renewable polymers were prepared by photo-polymerization of these modified vegetable oils with typical thiol monomers: pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tris (3-mercaptopropionate) and 1,2-ethanedithiol. The synthesis of the vinyl oligomer was monitored by nuclear magnetic resonance and Fourier-transform infrared spectroscopy. The average number of the carbon-carbon double bonds of the resulting vinyl oligomer is high to be 7.2. The kinetic… More >

  • Open Access

    ARTICLE

    Studies on Physical Chemistry of Rubber-Rice Husk Ash Composites

    V. Subrahmanian1,*, M. Albert Noble Einstien2

    Journal of Renewable Materials, Vol.7, No.2, pp. 171-192, 2019, DOI:10.32604/jrm.2019.00090

    Abstract Nowadays an alternate source of filler from renewable and plant derivatives are being thought of in rubber industries due to their reliability, environmental and economic benefits. Rice Husk Ash (RHA) a byproduct of the rice milling industry is obtained on partial and as well as full combustion of the rice husks. This ash is a good source of silica, silicates and needle shaped carbon and hence can be used as filler for cements. In the present study, a detailed investigation was carried out to understand the RHA as reinforcing material using mechanical properties and fractography using SEM. The rubbers studied… More >

  • Open Access

    ARTICLE

    Novel Membranes Regenerated from Blends of Cellulose/Gluten Using Ethylenediamine/Potassium Thiocyanate Solvent System

    Yang Yu1, Ramiz Boy1,2,*, Richard Kotek1

    Journal of Renewable Materials, Vol.7, No.1, pp. 41-55, 2019, DOI:10.32604/jrm.2019.00105

    Abstract Current industrial methods for dissolution of cellulose in making regenerated cellulose products are relatively expensive, toxic and dangerous and have environmental problems coming with the hazard chemical wastes. To solve these problems, a novel ethylenediamine and potassium thiocyanate (ED/KSCN) solvent system was developed, that is economical, ecofriendly, and highly efficient. The ED/KSCN solvent system was proven to be a suitable solvent for fabricating cellulose (blended with other polymers) membranes. In this study, gluten was used to develop nonporous membranes with cellulose. The method of casting these membranes provided better ones than the former researchers’ techniques. These composite membranes’ physical and… More >

  • Open Access

    ARTICLE

    Enzymatic Synthesis of Polycaprolactone: Effect of Immobilization Mechanism of CALB on Polycaprolactone Synthesis

    Yasemin Kaptan, M.Sc.1,*, Yüksel Avcıbaşı-Güvenilir1

    Journal of Renewable Materials, Vol.6, No.6, pp. 619-629, 2018, DOI:10.32604/JRM.2018.00142

    Abstract Surface-modified rice husk ash was used as an inorganic support material for immobilization of Candida antarctica lipase B. (3-aminopropyl) trimethoxysilane was used for surface modification. Immobilization of CALB was performed via both physical adsorption and cross-linking. PCL synthesis was carried out by using these immobilized enzymes, free enzyme and Novozyme 435®. Molecular weight distribution of polymer samples was obtained by gel permeation chromatography (GPC) and chain structures of the polymer samples were observed by hydrogen nuclear magnetic resonance (1H-NMR). The highest monomer conversion is generally obtained by using cross-linked enzyme, around 90%. PDI values for all polymer samples were approximately… More >

  • Open Access

    ABSTRACT

    Segmentation and simulation of objects represented in images using physical principles

    Patrícia C.T. Gonçalves1,2, João Manuel R.S. Tavares1, R.M. Natal Jorge1

    The International Conference on Computational & Experimental Engineering and Sciences, Vol.9, No.3, pp. 203-204, 2009, DOI:10.3970/icces.2009.009.203

    Abstract The main goals of the present work are to automatically extract the contour of an object and to simulate its deformation using a physical approach. In this work, to segment an object represented in an image, an initial contour is manually defined for it that will then automatically evolve until it reaches the border of the desired object. In this approach, the contour is modelled by a physical formulation using the finite element method, and its temporal evolution to the desired final contour is driven by internal and external forces. The internal forces are defined by the intrinsic characteristics of… More >

  • Open Access

    ARTICLE

    Particleboard Based on Rice Husk: Effect of Binder Content and Processing Conditions

    E. M. Ciannamea, D. C. Marin, R. A. Ruseckaite, P. M. Stefani*

    Journal of Renewable Materials, Vol.5, No.5, pp. 357-362, 2017, DOI:10.7569/JRM.2017.634125

    Abstract In the development of materials based on renewable resources, the search for lignocellulosic substitutes for wood is one of the biggest challenges that academia and the particleboard and wood industries are facing. In this article, particleboards were processed using rice husk, an agricultural waste, as a substitute for wood. Rice husk without any further treatment was processed into particleboards using phenol-formaldehyde resin as binder. The effect of the processing parameters, pressure and binder content (BC) on the density, water absorption (WA), thickness swelling (TS), modulus of rupture (MOR) and modulus of elasticity (MOE) was analyzed. The performance of the obtained… More >

  • Open Access

    ARTICLE

    Variation of Physical Properties of Rigid Polyurethane Foams Synthesized from Renewable Sources with Different Commercial Catalysts

    Daniel Brenes-Granados1, Jorge M. Cubero-Sesin1,2, Felipe Orozco Gutiérrez3, Jose Vega-Baudrit3, Rodolfo Gonzalez-Paz3*

    Journal of Renewable Materials, Vol.5, No.3-4, pp. 280-289, 2017, DOI:10.7569/JRM.2017.634118

    Abstract In this work, rigid polyurethane foams were synthesized from renewable sources using different catalysts to study their effect on the mechanical, thermal, chemical and surface properties of the foams. A commercial foam pattern was used as the reference pattern to compare the aforementioned properties. Concentrations of the commercial catalysts were optimized to obtain foams with similar mechanical properties to the commercial foam. Morphological characterization of the foams was performed by scanning electron microscopy (SEM). Fourier transform infrared (FTIR) spectroscopy was employed to investigate the characteristic functional groups. Thermal characterization was performed by means of differential scanning calorimetry (DSC) and thermogravimetric… More >

  • Open Access

    ARTICLE

    Fast Force Loading Disrupts Molecular Binding Stability in Human and Mouse Cell Adhesions

    Yunfeng Chen1,2,3,†,*, Jiexi Liao4,†, Zhou Yuan1, Kaitao Li4, Baoyu Liu4, Lining Arnold Ju4,5,6, Cheng Zhu1,2,4,*

    Molecular & Cellular Biomechanics, Vol.16, No.3, pp. 211-223, 2019, DOI:10.32604/mcb.2019.07267

    Abstract Force plays critical roles in cell adhesion and mechano-signaling, partially by regulating the dissociation rate, i.e., off-rate, of receptor-ligand bonds. However, the mechanism of such regulation still remains elusive. As a controversial topic of the field, when measuring the “off-rate vs. force” relation of the same molecular system, different dynamic force spectroscopy (DFS) assays (namely, force-clamp and force-ramp assays) often yield contradictive results. Such discrepancies hurdled our further understanding of molecular binding, and casted doubt on the existing theoretical models. In this work, we used a live-cell DFS technique, biomembrane force probe, to measure the single-bond dissociation in three receptor-ligand… More >

  • Open Access

    REVIEW

    Biophysical approaches for studying the integrity and function of tight junctions

    S.R.K. Vedula1, T.S. Lim2, P.J. Kausalya3, W. Hunziker3, G. Rajagopal2, C.T. Lim1,4

    Molecular & Cellular Biomechanics, Vol.2, No.3, pp. 105-124, 2005, DOI:10.3970/mcb.2005.002.105

    Abstract Cell-cell adhesion is an extremely important phenomenon as it influences several biologically important processes such as inflammation, cell migration, proliferation, differentiation and even cancer metastasis. Furthermore, proteins involved in cell-cell adhesion are also important from the perspective of facilitating better drug delivery across epithelia. The adhesion forces imparted by proteins involved in cell-cell adhesion have been the focus of research for sometime. However, with the advent of nanotechnological techniques such as the atomic force microscopy (AFM), we can now quantitatively probe these adhesion forces not only at the cellular but also molecular level. Here, we review the structure and function… More >

Displaying 161-170 on page 17 of 190. Per Page