Optimizing cellulose fibrillation for the production of cellulose nanofibrils by a disk grinder

Holzforschung ◽  
2015 ◽  
Vol 69 (8) ◽  
pp. 993-1000 ◽  
Author(s):  
Chuanshuang Hu ◽  
Yu Zhao ◽  
Kecheng Li ◽  
J.Y. Zhu ◽  
Roland Gleisner
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Energy Consumption ◽  
Cellulose Nanofibrils ◽  
Solid Loading ◽  
Cumulative Energy ◽  
Microscopy Imaging ◽  
Rotating Speed ◽  
Wide Range ◽  
Scanning Electron

Abstract The fibrillation of a bleached kraft eucalyptus pulp was investigated by means of a laboratory-scale disk grinder for the production of cellulose nanofibrils (CNF), while the parameters disk rotating speed, solid loading, and fibrillation duration were varied. The cumulative energy consumption was monitored during fibrillation. The degree of polymerization (DP) and water retention value (WRV) of the resultant cellulose fibrils were determined as measures of the degree of fibrillation, which was also visualized by scanning electron microscopy, field emission-scanning electron microscopy, and transmission electron microscopy imaging. A higher rotating speed than 1500 rpm did not improve the fibrillation judged by DP and WRV measurements. Solid loading has an insignificant effect on fibrillation in a wide range. The energy consumption (E) was determined as a function of the DP and WRV. The optimal grinding conditions were between 1200 and 1500 rpm at 2.0%–2.2% solid loading.

scholarly journals Intraocular lens biofilm formation supported by scanning electron microscopy imaging

2019 ◽  
Vol 67 (10) ◽  
pp. 1708
Author(s):  
Dipankar Das ◽  
Harsha Bhattacharjee ◽  
Krishna Gogoi ◽  
JayantaK Das ◽  
Puneet Misra ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Intraocular Lens ◽  
Biofilm Formation ◽  
Microscopy Imaging ◽  
Scanning Electron

Characterization of Friction Stir Welding on Aluminum

2009 ◽  
Vol 68 ◽  
pp. 167-174 ◽  
Author(s):  
Jerry Wong ◽  
Patricia del C. Zambrano ◽  
Martha Patrizia Guerrero-Mata ◽  
Victor Mucino ◽  
Rafael Colás
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Carrying Capacity ◽  
Feeding Rate ◽  
Load Carrying Capacity ◽  
Rotating Speed ◽  
Friction Stir ◽  
Load Carrying ◽  
Scanning Electron

A series of linear and spot stir welding friction tests were carried out on aluminum samples of 1 mm in thickness and area of 100 mm x 27 mm. The tool rotating speed was varied from 2000 to 4000 RPM and the feeding rate from 45 to 67.8 mm/min. The temperature distribution during welding was measured by thermocouples inserted within the aluminum strips. The microstructure of the welded nuggets and the HAZ were analyzed by optical and scanning electron microscopy. Some samples were tested intension to measure the load carrying capacity of the welded bead. Preliminary analyses indicate that the temperature at the heat affected zone increases with the rotating speed.

Delamination Behavior of Cu-Low-k Stack Under Different Slurries

2003 ◽  
Vol 767 ◽  
Author(s):  
A. K. Sikder ◽  
S. Thagella ◽  
P. B. Zantye ◽  
Ashok Kumar
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Chemical Mechanical Polishing ◽  
Wear Behavior ◽  
Polished Surface ◽  
Cu Metallization ◽  
Wide Range ◽  
Low K ◽  
Delamination Behavior ◽  
Scanning Electron

AbstractLower mechanical strength, reduced cohesive strength and lack of compatibility with other interconnect materials, are the major challenges involved in chemical mechanical polishing (CMP) of Cu metallization with ultra low-k materials as interlayer dielectrics. In this study we have investigated the polishing behavior of patterned Cu samples with underneath different low-k materials using two different slurries and a wide range of machine parameters. CMP micro tribometer was used to polish the samples with different rotations of platen (50 to 250 RPM) and down forces (1-6 PSI). Friction co-efficient and wear behavior were also investigated at different conditions. Optical and scanning electron microscopy was used to investigate the polished surface. It was observed that the two different Cu slurries used for polishing have marked effects on the polishing of Cu-low-k stack with respect to wear and delamination.

scholarly journals Correlation of X-ray Computed Nanotomography and Scanning Electron Microscopy Imaging of Collagen Scaffolds

2018 ◽  
Vol 24 (S2) ◽  
pp. 104-105
Author(s):  
Dominika Kalasova ◽  
Veronika Pavlinakova ◽  
Tomas Zikmund ◽  
Lucy Vojtova ◽  
Jozef Kaiser
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Collagen Scaffolds ◽  
Microscopy Imaging ◽  
X Ray ◽  
X Ray Computed ◽  
Scanning Electron

scholarly journals Dry Sliding Tribological Properties of a Hard Anodized AA6082 Aluminum Alloy

Metals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 207
Author(s):  
Eleonora Santecchia ◽  
Marcello Cabibbo ◽  
Abdel Magid Salem Hamouda ◽  
Farayi Musharavati ◽  
Anton Popelka ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Wear Behavior ◽  
Structure Characterization ◽  
Dry Sliding Wear ◽  
Dry Sliding ◽  
Alumina Layer ◽  
Wide Range ◽  
Wear Tests ◽  
Scanning Electron

The applications of aluminum and its alloys are still limited by low hardness and low wear resistance properties. Surface modifications, such anodizing and plasma electrolytic oxidation, represent a feasible way to overcome these drawbacks. In this study, discs of AA6082 were subjected to the so-called G.H.A. hard anodizing process leading to an anodized layer having a honeycomb-like structure. Samples having alumina layer thicknesses of 10, 50 and 100 μm were subjected to unidirectional dry sliding wear tests, using bearing steel and silicon nitride as counterbody materials. Surface and structure characterization of the samples were performed before and after the tribological tests, using a wide range of techniques; atomic force microscopy and scanning electron microscopy techniques were used before the wear tests. The wear scars were characterized by scanning electron microscopy, energy dispersive spectroscopy and Fourier transform infrared spectroscopy techniques. Results show that the different thickness of the anodized layer does not affect the pores dimensions but has an influence on the micrometric domains in which the pores are divided. These features coupled with the wear test conditions, show to have a strong influence on the wear behavior. The thinnest sample showed also the best performance against the ceramic counterbody.

scholarly journals In Vitro Effect of Modified Polyetheretherketone (PEEK) Implant Abutments on Human Gingival Epithelial Keratinocytes Migration and Proliferation

Materials ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1401 ◽  
Author(s):  
Liza L. Ramenzoni ◽  
Thomas Attin ◽  
Patrick R. Schmidlin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Tetrazolium Salt ◽  
Microscopy Imaging ◽  
Implant Abutments ◽  
And Migration ◽  
Vitro Effect ◽  
Scanning Electron ◽  
Proliferation And Migration

Improving soft tissue attachment to implant abutments is a crucial factor for enduring health and maintenance of soft peri-implant tissue health. In this in vitro study we aimed to compare the biocompatibility of three different abutment surfaces: titanium, zirconia and modified polyetheretherketone (PEEK). Surface topography, roughness and wettability were investigated with scanning electron microscopy, profilometer and contact angle meter, respectively. Human gingival epithelial keratinocytes were examined for viability, morphology, proliferation and migration by using tetrazolium salt colorimetric assay, scanning electron microscopy imaging, immunofluorescence bromodeoxyuridine analysis and scratch wound healing assays. Roughness measurements revealed differences between the investigated surfaces. Keratinocytes cultured on all examined surfaces indicated adhesion and attachment by means of scanning electron microscopy imaging. Cell viability assays showed no significant differences between the groups (p > 0.05). The modified PEEK surface similarly improved surface roughness in comparison to titanium and zirconia, which resulted in greater and equivalent cell proliferation and migration. The study methodology showed here may emphasize the importance of cell interactions with different abutment materials, which in part increases the changes of implant success. PEEK, titanium and zirconia surface types used in this study showed mostly similar epithelial biological responses.

Sign in / Sign up

Export Citation Format

Share Document