scholarly journals Physical and Acoustical Properties of Corn Husk Fiber Panels

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Nasmi Herlina Sari ◽  
I. N. G. Wardana ◽  
Yudy Surya Irawan ◽  
Eko Siswanto
Keyword(s):  
Sound Absorption ◽  
Natural Fibers ◽  
Physical And Mechanical Properties ◽  
Tensile Tests ◽  
Scanning Electron Micrographs ◽  
Acoustical Properties ◽  
Corn Husk ◽  
Morphological Aspects ◽  
Scanning Electron ◽  
Better Than

This research focuses on the development of a sustainable acoustic material comprising natural fibers of corn husk that were alkali modified by 1%, 2%, 5%, and 8% NaOH. The morphology and the acoustical, physical, and mechanical properties of the resulting fibers were experimentally investigated. Five different types of sample were produced in panel form, the acoustical properties of which were studied using a two-microphone impedance tube test. The porosity, tortuosity, and airflow resistivity of each panel were investigated, tensile tests were conducted, and the morphological aspects were evaluated via scanning electron microscopy. The sound absorption and tensile properties of the treated panels were better than those of raw fiber panels; the treated panels were of high airflow resistivity and had low porosity. Scanning electron micrographs of the surfaces of the corn husk fibers revealed that the different sound absorption properties of these panels were due to roughness and the lumen structures.

scholarly journals Characterisation of interfacial adhesion in hemp composites after H2O2 and non-thermal plasma treatments

2021 ◽  
pp. 002199832110154
Author(s):  
Romain Barbière ◽  
Fabienne Touchard ◽  
Laurence Chocinski-Arnault ◽  
Elodie Fourré ◽  
Eric Leroy ◽  
...  
Keyword(s):  
Thermal Plasma ◽  
Interfacial Shear Strength ◽  
Tensile Tests ◽  
Micro Ct ◽  
Interface Adhesion ◽  
Morphological Aspects ◽  
Non Thermal Plasma ◽  
A Current ◽  
Selection Of ◽  
Better Than

Interface optimisation for continuous hemp reinforcements in epoxy resin is a current challenge for the development of biocomposites. A chemical treatment based on hydrogen peroxide and a physical one using a non-thermal plasma have been tested to optimise interface adhesion, by varying several parameters. FTIR analysis and FE-SEM observations have shown the effects of the treatments on chemical and morphological aspects of the treated yarns. Tensile tests on hemp yarns have allowed the selection of the treatment parameters leading to the best strength. Fragmentation tests results showed that the two treatments lead to a decrease in the fragment lengths and thus, an enhancement of the Interfacial Shear Strength (IFSS) values in comparison with the untreated yarn. This is confirmed by the micro-CT observations of the debonding lengths in the vicinity of each yarn fragment extremity. Finally, the plasma treated samples exhibit a better interface adhesion quality (IFSS = 44.7 ± 4 MPa) than the chemically treated ones (IFSS = 24.2 ± 4 MPa), which are better than the non-treated ones (IFSS = 13.5 ± 4 MPa).

Scanning Electron Microscopy Using Cathodoluminescence

1967 ◽  
Vol 25 ◽  
pp. 122-123 ◽  
Author(s):  
R. F. W. Pease ◽  
T. L. Hayes
Keyword(s):  
Electron Microscope ◽  
Ultra Violet ◽  
Scanning Electron Micrographs ◽  
Secondary Electrons ◽  
Probe Diameter ◽  
Similar Information ◽  
Molecular Information ◽  
Optical Focusing ◽  
Scanning Electron ◽  
Better Than

It is desirable to derive molecular information from many specimens with a resolution better than can be achieved with a light microscope. In the conventional electron microscope such information is usually only obtained indirectly by staining the specimen with a stain containing a heavy metal.In the scanning electron microscope (SEM), the optical focusing is independent of the contrast process; this allows a wide variety of contrast mechanisms e.g. secondary electrons emission which gives information of surface topography and voltage, and X ray emission which reveals atomic content.Some specimens emit light when bombarded with electrons. This process, cathodoluminescence, is characteristic of the molecular content of biological specimens and therefore we are investigating using this emitted light to build up scanning electron micrographs. Although similar information can be obtained using ultra violet fluoresence microscopy, the scanning electron technique offers the possibility of improved resolution since this is limited fundamentally by the electron probe diameter which can be 50Å or smaller.

Natural-Fiber-Reinforced Polymer Composites for Automotive Parts Manufacturing

2019 ◽  
Vol 793 ◽  
pp. 9-16 ◽  
Author(s):  
Bernado Oliver-Borrachero ◽  
S. Sánchez-Caballero ◽  
Octavio Fenollar ◽  
M.A. Sellés
Keyword(s):  
Composite Materials ◽  
Natural Fiber ◽  
Natural Fibers ◽  
Physical And Mechanical Properties ◽  
Tensile Tests ◽  
Finite Element Software ◽  
Automotive Components ◽  
Fiber Reinforced Polymer Composites ◽  
Automotive Parts ◽  
Parts Manufacturing

Composite materials are widely used in the industry for their physical and mechanical properties. The objective of this work is the characterization of some composite materials with natural fibers, in order to determine the suitability in a later use in automotive components. For this purpose, we intend to obtain a model of tensile tests using finite element software, in order to be able to dimension real components.

Revision of the Afrotropical flea beetle genus Collartaltica Bechyné with description of two new species (Coleoptera, Chrysomelidae, Alticinae)

2004 ◽  
Vol 35 (3) ◽  
pp. 285-298 ◽  
Author(s):  
◽  
Keyword(s):  
New Species ◽  
Flea Beetle ◽  
Cladistic Analysis ◽  
Scanning Electron Micrographs ◽  
Male And Female ◽  
Line Drawings ◽  
Morphological Aspects ◽  
Afrotropical Region ◽  
Two New Species ◽  
Scanning Electron

AbstractThe known species of the flea beetle genus Collartaltica Bechyné, endemic to the Afrotropical Region, are revised. A brief diagnosis of the genus is given and two new species, C. meridionalis sp.n. and C. alluaudi sp.n., respectively from the Southern Africa and Kenya, are described. Line drawings of male and female genitalia and scanning electron micrographs of particular morphological aspects of the species considered are also included. Finally, a cladistic analysis of this genus using maximum parsimony is presented.

Electron Microscopic Observation of the Longitudinal Organization of Poly (p-Phenylene Terephthalamide) Fibers

1982 ◽  
Vol 40 ◽  
pp. 680-681
Author(s):  
Li Li-Sheng ◽  
L.F. Allard ◽  
W.C. Bigelow
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Microscopic Observation ◽  
Electron Microscopic Observation ◽  
Electron Microscopic ◽  
Aromatic Polyamides ◽  
Radial Arrangement ◽  
Scanning Electron ◽  
Better Than

The aromatic polyamides form a class of fibers having mechanical properties which are much better than those of aliphatic polyamides. Currently, the accepted morphology of these fibers as proposed by M.G. Dobb, et al. is a radial arrangement of pleated sheets, with the plane of the pleats parallel to the axis of the fiber. We have recently obtained evidence which supports a different morphology of this type of fiber, using ultramicrotomy and ion-thinning techniques to prepare specimens for transmission and scanning electron microscopy.

Resolution and measurement in the scanning electron microscope

1987 ◽  
Vol 45 ◽  
pp. 534-537 ◽  
Author(s):  
Michael T. Postek
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Engineering Design ◽  
Resolving Power ◽  
Practical Applications ◽  
Instrument Resolution ◽  
Accurate Definition ◽  
Definition Of ◽  
Scanning Electron ◽  
Better Than

The term ultimate resolution or resolving power is the very best performance that can be obtained from a scanning electron microscope (SEM) given the optimum instrumental conditions and sample. However, as it relates to SEM users, the conventional definitions of this figure are ambiguous. The numbers quoted for the resolution of an instrument are not only theoretically derived, but are also verified through the direct measurement of images on micrographs. However, the samples commonly used for this purpose are specifically optimized for the measurement of instrument resolution and are most often not typical of the sample used in practical applications.SEM RESOLUTION. Some instruments resolve better than others either due to engineering design or other reasons. There is no definitively accurate definition of how to quantify instrument resolution and its measurement in the SEM.

Scanning Secondary Electron Microscopy of Myofibrils Using Transmission Techniques

1975 ◽  
Vol 33 ◽  
pp. 556-557
Author(s):  
M. K. Lamvik
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Carbon Films ◽  
Photographic Recording ◽  
Transmission Electron ◽  
Thin Carbon ◽  
The Common ◽  
Scanning Electron ◽  
Better Than ◽  
Cellular Organelles

When observing small objects such as cellular organelles by scanning electron microscopy, it is often valuable to use the techniques of transmission electron microscopy. The common practice of mounting and coating for SEM may not always be necessary. These possibilities are illustrated using vertebrate skeletal muscle myofibrils.Micrographs for this study were made using a Hitachi HFS-2 scanning electron microscope, with photographic recording usually done at 60 seconds per frame. The instrument was operated at 25 kV, with a specimen chamber vacuum usually better than 10-7 torr. Myofibrils were obtained from rabbit back muscle using the method of Zak et al. To show the component filaments of this contractile organelle, the myofibrils were partially disrupted by agitation in a relaxing medium. A brief centrifugation was done to clear the solution of most of the undisrupted myofibrils before a drop was placed on the grid. Standard 3 mm transmission electron microscope grids covered with thin carbon films were used in this study.

scholarly journals Characterization of Beeswax, Candelilla Wax and Paraffin Wax for Coating Cheeses

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 261
Author(s):  
Adolfo Bucio ◽  
Rosario Moreno-Tovar ◽  
Lauro Bucio ◽  
Jessica Espinosa-Dávila ◽  
Francisco Anguebes-Franceschi
Keyword(s):  
Physical And Mechanical Properties ◽  
Tensile Tests ◽  
Paraffin Wax ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Absorption Bands ◽  
Dimensional Changes ◽  
Ductile Behavior ◽  
Candelilla Wax

A study on the physical and mechanical properties of beeswax (BW), candelilla wax (CW), paraffin wax (PW) and blends was carried out with the aim to evaluate their usefulness as coatings for cheeses. Waxes were analyzed by X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), differential scanning calorimetry (DSC), permeability, viscosity, flexural and tensile tests and scanning electron microscopy. Cheeses were coated with the waxes and stored for 5 weeks at 30 °C. Measured parameters were weight, moisture, occurrence and degree of fractures, and dimensional changes. The crystal phases identified by XRD for the three waxes allowed them to determine the length of alkanes and the nonlinear compounds in crystallizable forms in waxes. FTIR spectra showed absorption bands between 1800 and 800 cm−1 related to carbonyls in BW and CW. In DSC, the onset of melting temperature was 45.5 °C for BW, and >54 °C for CW and PW. Cheeses coated with BW did not show cracks after storage. Cheeses coated with CW and PW showed microcraks, and lost weight, moisture and shrunk. In the flexural and tensile tests, BW was ductile; CW and PW were brittle. BW blends with CW or PW displays a semi ductile behavior. Cheeses coated with BW blends lost less than 5% weight during storage. The best waxes were BW and the blends.

Optimization and Modeling of Sound-Absorption Properties of Natural Fibers for Acoustical Application

2021 ◽  
pp. 1-17
Author(s):  
Seyed Ehsan Samaei ◽  
Ebrahim Taban ◽  
Umberto Berardi ◽  
Seyyed Mohammad Mousavi ◽  
Mohammad Faridan ◽  
...  
Keyword(s):  
Sound Absorption ◽  
Natural Fibers ◽  
Absorption Properties

Effect of Castor Oil Impregnation on the Physical and Mechanical Properties of Bacterial Cellulose

2012 ◽  
Vol 3 (1) ◽  
pp. 13-26
Author(s):  
Myrtha Karina ◽  
Lucia Indrarti ◽  
Rike Yudianti ◽  
Indriyati
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Bacterial Cellulose ◽  
Young’S Modulus ◽  
Castor Oil ◽  
Young's Modulus ◽  
Physical And Mechanical Properties ◽  
Scanning Electron Micrographs ◽  
Elongation At Break ◽  
Acetone Water

The effect of castor oil on the physical and mechanical properties of bacterial cellulose is described. Bacterial cellulose (BC) was impregnated with 0.5–2% (w/v) castor oil (CO) in acetone–water, providing BCCO films. Scanning electron micrographs revealed that the castor oil penetrated the pores of the bacterial cellulose, resulting in a smoother morphology and enhanced hydrophilicity. Castor oil caused a slight change in crystallinity indices and resulted in reduced tensile strength and Young's modulus but increased elongation at break. A significant reduction in tensile strength and Young's modulus was achieved in BCCO films with 2% castor oil, and there was an improvement in elongation at break and hydrophilicity. Impregnation with castor oil, a biodegradable and safe plasticiser, resulted in less rigid and more ductile composites.

Sign in / Sign up

Export Citation Format

Share Document