scholarly journals Surface Wetting and Energy Properties of Cellulose Acetate, Polyester and Polypropylene Fibers

1999 ◽  
Vol os-8 (1) ◽  
pp. 1558925099OS-80
Author(s):  
Bhupender S. Gupta ◽  
Hyun Suk Whang
Keyword(s):  
Cellulose Acetate ◽  
Contact Angles ◽  
Work Of Adhesion ◽  
Surface Wetting ◽  
Cross Sectional ◽  
Fiber Size ◽  
Receding Contact ◽  
Sectional Shape ◽  
Wetting Behaviors ◽  
Wetting Force

Using a dynamic wetting force device, involving a sensitive Wilhelmy balance, surface wetting behaviors of polyester, polypropylene, and cellulose acetate fibers, the last two in several different sizes and cross-sectional shapes, were examined. Assessed were the values of the advancing and the receding contact angles and the work of adhesion with water as the fluid. Conducting tests with deionized water and methylene iodide allowed us to assess the value of the total surface energy along with the values of the polar and the dispersion components of it. In a limited number of tests, the surface properties of polyester and polypropylene films were also determined and compared with those of the fibers. The results generally showed that the energy was largely dispersive, hysteresis in contact angles was low, and while the fiber size and cross-sectional shape did not influence the contact angles or the energy, the surface roughness and crystallinity played significant roles.

Wettability and Interfacial Interactions of Amorphous Titanium Treated by Ion Implantation

1997 ◽  
Vol 11 (19) ◽  
pp. 829-839 ◽  
Author(s):  
N. S. Athanasiou
Keyword(s):  
Dynamic Contact ◽  
Contact Angles ◽  
Work Of Adhesion ◽  
Dispersive Surface Energy ◽  
Angle Measurements ◽  
Three Samples ◽  
Contact Angle Measurements ◽  
Receding Contact ◽  
Titanium Grade ◽  
Dynamic Angle

This work concerns with an investigation of the wettability properties of C +, O + and Cr + implanted titanium (grade 2) plates using multienergetically implantation with a resulting dose of 1 × 1017 ions/cm 2 and energies in the order of 50 to 180 keV. Dynamic contact angles were investigated using the Wilhelmy technique with the standard stage speed 20×10-6 m/s in distilled water at T = 293 ± 1 K, performed by the Cahn Dynamic Angle Analyzer (DCAA). For each measurement three samples with the same geometrical and implantation parameters were used. For each sample three tests were performed. We found, that the average receding contact angles lie in the range of 49.45 to 61.67 degrees. Using the results of the interaction energy calculations in receding cycle, we found that the work of adhesion is almost similar in the case of titanium (117.2 mJ/m2) and C + implanted titanium (119.6 mJ/m2). Smaller values (approx. 107 mJ/m2) were obtained in the case of O + and Cr + implanted titanium. On the other hand, comparison with results obtained on unimplanted and N +, O + and Cr + implanted titanium alloy (Ti-6Al-4V) prepared at the same conditions, shows that the corresponding work of adhesion (ranged from 135 to 145 mJ/m2) is relatively higher than those of unmodified and modified titanium. Additionally, the resulting dispersive surface energy (ranged from 75 to 87.20 mJ/m2) based on advancing contact angle measurements on unimplanted and implanted titanium, is in good agreement with experimental data obtained in Mn, Fe or Ag metals.

On the cross-sectional shape of the cellulose crystallites in the tunicate Halocynthia papillosa

1990 ◽  
Vol 48 (3) ◽  
pp. 566-567
Author(s):  
J.-F. Revol ◽  
Y. Van Daele ◽  
F. Gaill
Keyword(s):  
Contrast Imaging ◽  
Animal Kingdom ◽  
Bright Field ◽  
Field Mode ◽  
Cross Sectional ◽  
Ultrathin Sections ◽  
The Cross ◽  
Sectional Shape ◽  
Valonia Ventricosa ◽  
C Nmr

The only form of cellulose which could unequivocally be ascribed to the animal kingdom is the tunicin that occurs in the tests of the tunicates. Recently, high-resolution solid-state l3C NMR revealed that tunicin belongs to the Iβ form of cellulose as opposed to the Iα form found in Valonia and bacterial celluloses. The high perfection of the tunicin crystallites led us to study its crosssectional shape and to compare it with the shape of those in Valonia ventricosa (V.v.), the goal being to relate the cross-section of cellulose crystallites with the two allomorphs Iα and Iβ.In the present work the source of tunicin was the test of the ascidian Halocvnthia papillosa (H.p.). Diffraction contrast imaging in the bright field mode was applied on ultrathin sections of the V.v. cell wall and H.p. test with cellulose crystallites perpendicular to the plane of the sections. The electron microscope, a Philips 400T, was operated at 120 kV in a low intensity beam condition.

Automated 3D measurement of fiber cross section morphology in handsheets

2012 ◽  
Vol 27 (2) ◽  
pp. 264-269 ◽  
Author(s):  
Christian Lorbach ◽  
Ulrich Hirn ◽  
Johannes Kritzinger ◽  
Wolfgang Bauer
Keyword(s):  
Image Analysis ◽  
Cross Section ◽  
Cross Sections ◽  
Image Plane ◽  
3D Measurement ◽  
Cross Sectional ◽  
Fiber Cross Section ◽  
Fiber Wall ◽  
Sectional Shape ◽  
Cross Section Geometry

Abstract We present a method for 3D measurement of fiber cross sectional morphology from handsheets. An automated procedure is used to acquire 3D datasets of fiber cross sectional images using an automated microtome and light microscopy. The fiber cross section geometry is extracted using digital image analysis. Simple sample preparation and highly automated image acquisition and image analysis are providing an efficient tool to analyze large samples. It is demonstrated that if fibers are tilted towards the image plane the images of fiber cross sections are always larger than the true fiber cross section geometry. In our analysis the tilting angles of the fibers to the image plane are measured. The resulting fiber cross sectional images are distorted to compensate the error due to fiber tilt, restoring the true fiber cross sectional shape. We use an approximated correction, the paper provides error estimates of the approximation. Measurement results for fiber wall thickness, fiber coarseness and fiber collapse are presented for one hardwood and one softwood pulp.

scholarly journals Study on contact angles and surface energy of MXene films

RSC Advances ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 5512-5520
Author(s):  
Hang Zhou ◽  
Fuqiang Wang ◽  
Yuwei Wang ◽  
Changping Li ◽  
Changrui Shi ◽  
...  
Keyword(s):  
Surface Energy ◽  
Contact Angles ◽  
Time Dependent ◽  
Wetting Behaviors

This work sheds light on the process- and time-dependent wetting behaviors and surface energy of MXene films.

Study of Correctly Expanded Sonic Jet with Air Tabs

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Arun Prasad R ◽  
Thanigaiarasu S ◽  
Sembaruthi M ◽  
Rathakrishnan E
Keyword(s):  
Numerical Study ◽  
Cross Sectional ◽  
Potential Core ◽  
Convergent Nozzle ◽  
Jet Mixing ◽  
Pressure Profiles ◽  
Constant Diameter ◽  
Sonic Jet ◽  
Sectional Shape ◽  
Length Reduction

AbstractThe present numerical study is to understand the effect of air tabs located at the exit of a convergent nozzle on the spreading and mixing characteristics of correctly expanded sonic primary jet. Air tabs used in this study are two secondary jets issuing from constant diameter tubes located diametrically opposite at the periphery of the primary nozzle exit, normal to the primary jet. Two air tabs of Mach numbers 1.0 to 1.4, in steps of 0.1 are considered in this study. The mixing modification caused by air tabs are analysed by considering the mixing of uncontrolled (free) primary jet as a reference. Substantial enhancement in jet mixing is achieved with Mach 1.4 air tabs, which results in 80 % potential core length reduction. The total pressure profiles taken on the plane (YZ) normal to the primary jet axis, at various locations along the primary jet centreline revealed the modification of the jet cross sectional shape by air tabs. The stream-wise vortices and bifurcation of the primary jet caused by air tabs are found to be the mechanism behind the enhanced jet mixing.

Experimental investigation and optimization on field shaper structure parameters in magnetic pulse welding

2021 ◽  
pp. 095440542110148
Author(s):  
Yingzi Chen ◽  
Zhiyuan Yang ◽  
Wenxiong Peng ◽  
Huaiqing Zhang
Keyword(s):  
Magnetic Field ◽  
High Speed ◽  
Light Metal ◽  
Magnetic Pulse ◽  
Cross Sectional ◽  
Magnetic Pulse Welding ◽  
Pulse Welding ◽  
Sectional Shape ◽  
Welding System ◽  
The Magnetic Field

Magnetic pulse welding is a high-speed welding technology, which is suitable for welding light metal materials. In the magnetic pulse welding system, the field shaper can increase the service life of the coil and contribute to concentrating the magnetic field in the welding area. Therefore, optimizing the structure of the field shaper can effectively improve the efficiency of the system. This paper analyzed the influence of cross-sectional shape and inner angle of the field shaper on the ability of concentrating magnetic field via COMSOL software. The structural strength of various field shapers was also analyzed in ABAQUS. Simulation results show that the inner edge of the field shaper directly affects the deformation and welding effect of the tube. So, a new shape of field shaper was proposed and the experimental results prove that the new field shaper has better performance than the conventional field shaper.

Blast Wave Shaping by Altering Cross‐Sectional Shape

2021 ◽  
Author(s):  
Kelly Williams ◽  
Martin J. Langenderfer ◽  
Gayla Olbricht ◽  
Catherine E. Johnson
Keyword(s):  
Blast Wave ◽  
Cross Sectional ◽  
Sectional Shape

Facile manipulation of receding contact angles of a substrate by roughening and fluorination

2015 ◽  
Vol 355 ◽  
pp. 127-132 ◽  
Author(s):  
Yueh-Feng Li ◽  
Cyuan-Jhang Wu ◽  
Yu-Jane Sheng ◽  
Heng-Kwong Tsao
Keyword(s):  
Contact Angles ◽  
Receding Contact

Eccentric ergometry: increases in locomotor muscle size and strength at low training intensities

2000 ◽  
Vol 278 (5) ◽  
pp. R1282-R1288 ◽  
Author(s):  
P. C. LaStayo ◽  
D. J. Pierotti ◽  
J. Pifer ◽  
H. Hoppeler ◽  
S. L. Lindstedt
Keyword(s):  
Energy Demand ◽  
Size Composition ◽  
Muscle Size ◽  
Trained Group ◽  
Cross Sectional ◽  
Functional Changes ◽  
Cycle Ergometers ◽  
Muscle Adaptations ◽  
Fiber Size ◽  
Skeletal Muscle Adaptations

Lengthening (eccentric) muscle contractions are characterized by several unusual properties that may result in unique skeletal muscle adaptations. In particular, high forces are produced with very little energy demand. Eccentrically trained muscles gain strength, but the specific nature of fiber size and composition is poorly known. This study assesses the structural and functional changes that occur to normal locomotor muscle after chronic eccentric ergometry at training intensities, measured as oxygen uptake, that do not influence the muscle when exercised concentrically. Male subjects trained on either eccentric or concentric cycle ergometers for 8 wk at a training intensity starting at 54% and ending at 65% of their peak heart rates. The isometric leg strength increased significantly in the eccentrically trained group by 36%, as did the cross-sectional area of the muscle fiber by 52%, but the muscle ultrastructure remained unchanged. There were no changes in either fiber size, composition, or isometric strength in the concentrically trained group. The responses of muscle to eccentric training appear to be similar to resistance training.

Sign in / Sign up

Export Citation Format

Share Document