scholarly journals Deformation behavior of wet lignocellulosic fibers

Holzforschung ◽  
2007 ◽  
Vol 61 (3) ◽  
pp. 261-266 ◽  
Author(s):  
Robert M. Lowe ◽  
Derek H. Page ◽  
John F. Waterhouse ◽  
Jeff Hsieh ◽  
Naveen Cheluka ◽  
...  
Keyword(s):  
Deformation Behavior ◽  
Step Height ◽  
Pulp Fibers ◽  
Lignocellulosic Fibers ◽  
Light Interference ◽  
Glass Slides ◽  
Main Effect ◽  
Wet Pressing ◽  
Analysis Computer ◽  
Dilute Suspension

Abstract The deformation behavior of wet lignocellulosic fibers was examined by applying a dilute suspension of dyed pulp fibers to a filter paper and then wet pressing the fibers onto glass slides. The geometry of single fiber crossing was determined using light interference and an image analysis computer program. The effects of pulp type, refining, wet pressing, drying and bleaching on the deformation behavior of pulp fibers were explored. The main effect of refining fibers was to reduce the step height for fiber-fiber crossings for both bleached and unbleached pulps by increasing the tendency of the cell wall to collapse and deform. All the pulps and treatments investigated maintained a relatively constant value for the step height/free span ratio.

Research on Characterization Methods of Nano Dimension Standards

2013 ◽  
Vol 662 ◽  
pp. 88-94
Author(s):  
Yuan Li ◽  
Jun Jie Wu ◽  
Li Hua Lei ◽  
Guo Fang Fan ◽  
Yun Xia Fu
Keyword(s):  
Standard Deviation ◽  
White Light ◽  
Step Height ◽  
Optical Methods ◽  
Characterization Methods ◽  
Average Value ◽  
Light Interference ◽  
Atomic Force ◽  
White Light Interference ◽  
1D Grating

This paper develops one method to characterize nano dimension standards using Scanning White Light Interference Sensor (SWLIS) based on Nano Measurement Machine (NMM). The experimental results show the average value of SHS8-440 low step height standard is 44.15 nm and SHS8-100.0 high step height standard is 100.29 μm, with a standard deviation of 0.30 nm and 0.03 μm, respectively. Also, SWLIS is performed to measure and characterize step height standards, which cover most of the conventional step height standards produced by VLSI Standards Incorporated (VLSI). Additionally, atomic force microscope (AFM) is used as a beneficial supplement due to low lateral resolution of optical methods. The average value of TGZ1_PTB 1D grating from NT-MDT Company is 3000.2 nm with a standard deviation of 0.3 nm by AFM.

Further understanding the response mechanism of lignin content to bonding properties of lignocellulosic fibers by their deformation behavior

RSC Advances ◽  
2016 ◽  
Vol 6 (110) ◽  
pp. 109211-109217 ◽  
Author(s):  
Zhiqiang Li ◽  
Hongjie Zhang ◽  
Xin Wang ◽  
Fengshan Zhang ◽  
Xiaoliang Li
Keyword(s):  
Deformation Behavior ◽  
Lignin Content ◽  
Response Mechanism ◽  
Bulk Properties ◽  
Lignocellulosic Fibers ◽  
Bonding Properties

The deformation behavior of lignocellulosic fibers was used to further understand the contradiction between their bonding and bulk properties.

Study on Spatial Frequency Domain Algorithm and White Light Interference System Based on NMM

2015 ◽  
Vol 738-739 ◽  
pp. 904-910
Author(s):  
Li Jian ◽  
Li Hua Lei ◽  
Dong Sheng Li ◽  
Yun Xia Fu ◽  
Yuan Li ◽  
...  
Keyword(s):  
Spatial Frequency ◽  
Frequency Domain ◽  
White Light ◽  
Three Dimensional ◽  
Step Height ◽  
Light Interference ◽  
Interference System ◽  
Measuring Machine ◽  
White Light Interference ◽  
Spatial Frequency Domain

White light interference technique for topography measurement effectively avoids phase ambiguity in phase-shifting interferometry. The spatial frequency domain algorithm based on scanning white light interference technique has the advantage of insensitivity to noise and higher calculation accuracy compared with other methods. The white light interference sensor is constructed based on nano positioning and nano measuring machine (NMM), the calibrated step height standard of 100±3nm is measured. The spatial frequency domain algorithm is adopted for data processing, the repetitive test result of 97.9nm and standard deviation of 0.48nm are achieved. To verify the measuring ability of complex device, the number ‘242’ on ink box is measured and three-dimensional reconstruction is conducted. The high precision and traceable measurements of micro/nano scale step height standard and complex devices are realized by the white light interference system based on NMM with steady frequency laser interferometer built-in.

A NOVEL STUDY ON SURFACE MODIFICATION OF PALMYRA FIBERS FOR ENHANCING MECHANICAL AND THERMAL PROPERTIES

2019 ◽  
Vol 27 (02) ◽  
pp. 1950104
Author(s):  
T. RAGHAVENDRA ◽  
K. PANNEERSELVAM
Keyword(s):  
Tensile Strength ◽  
Natural Fiber ◽  
Crystallinity Index ◽  
Mechanical And Thermal Properties ◽  
X Ray Diffraction ◽  
Energy Dispersion Spectroscopy ◽  
Lignocellulosic Fibers ◽  
Degradation Temperature ◽  
Main Effect ◽  
Increasing Temperature

Natural fiber reinforcing in engineering thermoplastics (Nylon melting point around 230∘C) is challenging, due to the lower degradation temperature ([Formula: see text]C) of lignocellulosic fibers. Further, increasing temperature (beyond 200∘C) results in weakening of its mechanical properties. In this investigation, camphor soot reinforced palmyra fibers (CSRPF) are manufactured by osmosis with the help of design of experiments (DOE) and are examined for different time (4, 8 and 12[Formula: see text]h), temperature (30∘C, 40∘C and 50∘C) and camphor soot concentrations (0.5, 1.0 and 1.5[Formula: see text]wt.%) using L9 orthogonal array. The osmosis rate of modified fibers was calculated and tested for their tensile strength as the osmosis rate and tensile strength are the main objective functions. Based on DOE and taguchi-ANOVA analysis, optimal parameters were obtained through main effect plots and Anova results. Further, an optimal combination of parameters for CSRPF was characterized for thermogravimetric analysis (TGA), Fourier transform infrared radiation (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersion spectroscopy (EDS) to inspect and compare it with neat palmyra fibers. There was considerable improvement in the CSRPF tensile strength about 84[Formula: see text]Mpa with respect to neat palmyra fibers which is 58[Formula: see text]MPa. TGA reveals the degradation temperature of neat palmyra fiber is about 225∘C and it is enhanced in case of CSRPF about 265∘C which accounts for 15% enhanced thermal stability. The crystallinity index (CI) of CSRPF was reduced marginally compared to the neat palmyra fibers. FTIR analysis showed the peak drift marginally to the left in CSRPF due to the coating of camphor soot particles. The microstructure of both neat and CSRPF are examined using SEM and EDS which shows that 93.71% carbon was present in the cross section of CSRPF compared to the neat palmyra fiber (62.58%).

Plastic deformation of θ ' in Al-4%Cu alloy

1978 ◽  
Vol 36 (1) ◽  
pp. 576-577
Author(s):  
Shrikant P. Bhat
Keyword(s):  
Deformation Behavior ◽  
Room Temperature ◽  
Electron Microscopic Observation ◽  
Bulk Alloy ◽  
Electron Microscopic ◽  
Cu Alloy ◽  
Cu Alloys ◽  
Orowan Mechanism ◽  
The Subject ◽  
Cyclic Straining

deformation behavior of Al-Cu alloys aged to contain θ ' has been the subject of many investigations (e.g., Ref. 1-5). Since θ ' is strong and hard, dislocations bypass θ ' plates (Orowan mechanism) at low strains. However, at high strains the partially coherent θ ' plates are probably sheared, although the mechanism is complex, depending on the form of deformation. Particularly, the cyclic straining of the bulk alloy is known to produce gross bends and twists of θ '. However, no detailed investigation of the deformation of θ ' has yet been reported; moreover, Calabrese and Laird interpreted the deformation of θ ' as largely being elastic.During an investigation of high temperature cyclic deformation, the detailed electron-microscopic observation revealed that, under reversed straining conditions, θ ' particles are severely distorted--bent and twisted depending on the local matrix constraint. A typical electronmicrograph, showing the twist is shown in Fig. 1. In order to establish whether the deformation is elastic or plastic, a sample from a specimen cycled at room temperature was heated inside the microscope and the results are presented in a series of micrographs (Fig. 2a-e).

Observation of secondary slip systems in tungsten bicrystals

1984 ◽  
Vol 42 ◽  
pp. 478-479
Author(s):  
J. R. Fekete ◽  
R. Gibala
Keyword(s):  
Stress Field ◽  
Grain Boundaries ◽  
Deformation Behavior ◽  
Stress Axis ◽  
Polycrystalline Materials ◽  
Slip Systems ◽  
Metallic Materials ◽  
Twist Boundary ◽  
Secondary Slip ◽  
Plane Normal

The deformation behavior of metallic materials is modified by the presence of grain boundaries. When polycrystalline materials are deformed, additional stresses over and above those externally imposed on the material are induced. These stresses result from the constraint of the grain boundaries on the deformation of incompatible grains. This incompatibility can be elastic or plastic in nature. One of the mechanisms by which these stresses can be relieved is the activation of secondary slip systems. Secondary slip systems have been shown to relieve elastic and plastic compatibility stresses. The deformation of tungsten bicrystals is interesting, due to the elastic isotropy of the material, which implies that the entire compatibility stress field will exist due to plastic incompatibility. The work described here shows TEM observations of the activation of secondary slip in tungsten bicrystals with a [110] twist boundary oriented with the plane normal parallel to the stress axis.

Processing Immunoperoxidase Labeled Cell Monolayers and Cryostat Sesctions For Electron Microscopy

1985 ◽  
Vol 43 ◽  
pp. 714-715
Author(s):  
K. Chien ◽  
R. Van de Velde ◽  
I.P. Shintaku ◽  
A.F. Sassoon
Keyword(s):  
Cell Monolayer ◽  
Cell Types ◽  
Surface Antigens ◽  
Immunoperoxidase Method ◽  
Reaction Step ◽  
Hot Plate ◽  
Air Drying ◽  
New Approach ◽  
Cell Monolayers ◽  
Glass Slides

Immunoelectron microscopy of neoplastic lymphoma cells is valuable for precise localization of surface antigens and identification of cell types. We have developed a new approach in which the immunohistochemical staining can be evaluated prior to embedding for EM and desired area subsequently selected for ultrathin sectioning.A freshly prepared lymphoma cell suspension is spun onto polylysine hydrobromide- coated glass slides by cytocentrifugation and immediately fixed without air drying in polylysine paraformaldehyde (PLP) fixative. After rinsing in PBS, slides are stained by a 3-step immunoperoxidase method. Cell monolayer is then fixed in buffered 3% glutaraldehyde prior to DAB reaction. After the DAB reaction step, wet monolayers can be examined under LM for presence of brown reaction product and selected monolayers then processed by routine methods for EM and embedded with the Chien Re-embedding Mold. After the polymerization, the epoxy blocks are easily separated from the glass slides by heatingon a 100°C hot plate for 20 seconds.

Detection of atrial natriuretic peptides (ANP) in rat atria by immunogold-silver staining (IGSS)

1994 ◽  
Vol 52 ◽  
pp. 304-305
Author(s):  
Robyn Rufner ◽  
Gerhard W. Hacker ◽  
Michele Forte ◽  
Nancyleigh E. Carson ◽  
Cristina Xenachis ◽  
...  
Keyword(s):  
Natriuretic Peptides ◽  
Silver Staining ◽  
Sodium Thiosulfate ◽  
Atrial Natriuretic Peptides ◽  
Paraffin Sections ◽  
Glass Slides ◽  
Metallic Salts ◽  
Wistar Kyoto ◽  
Right Atria

The use of immunogold-silver staining (IGSS) to enhance label penetration and Localization for immunocytochemistry or in situ hybridization utilizing a variety of metallic salts has been documented. In this morphological study, the effects of silver acetate, silver lactate and silver nitrate were evaluated for immunogold-labeling of a trial natriuretic peptides (ANP) in rat right atria.Eight Wistar Kyoto retired breeders were sedated with pentobarbital, perfused with either 4% paraformaldehyde (LM) or Karnovsky's fixative (EM), and right atria were dissected, processed, embedded in paraffin or epon, respectively and sectioned according to conventional methods. For light microscopy, an indirect IGSS method according to Hacker (3) was performed. Paraffin sections on glass slides were washed in ddH2O, immersed in Lugol's iodine, washed in ddH2O and treated with 2.5% aqueous sodium thiosulfate for 20 sec. After additional washes in ddH2O and TBS-0.1% fish gelatin, 10% normal goat serum (PBS with 1% BSA) was applied for 20 min before an overnight incubation at 4°C with a polyclonal α-ANP primary antibody (Peninsula Labs, 1:1000 in TBS/BSA).

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