Measurement of 3-D Orientation and 3-D Orientation Tensors in Polymer/Nanofiber Composites

2007 ◽  
Author(s):  
Monon Mahboob ◽  
Stephen E. Bechtel
Keyword(s):  
Fiber Orientation ◽  
Special Section ◽  
Three Dimensional ◽  
Processing Technique ◽  
Distribution Functions ◽  
Probability Distribution Functions ◽  
Transmission Electron ◽  
Polymer Nanofiber ◽  
Orientation Tensors ◽  
Novel Method

We present a novel method to compute the three dimensional orientation tensors of carbon nanofibers in CNF/polymer composites. Performance properties of nanofiber composites are significantly affected by fiber orientation patterns. So an accurate description of the fiber orientation is necessary to validate models relating processing technique and properties of the final composites. Orientation tensors and probability distribution functions (PDF) are commonly used to describe orientation patterns. But physical dimensions of nanofibers and the imaging technique (Transmission Electron Microscopy, TEM) make all currently available methods of image analysis useless to accurately computing these descriptions in 3-dimensions. In this study TEM sections are cut with specific thickness and angle that result in majority of the fibers being cut at both ends. Fiber projection dimensions measured from this special section provide the complete three dimensional orientation of each fiber. This method is benchmarked by using simulated 3D samples in AutoCAD.

A Novel Method to Analyze the Deep Trench Capacitors in DRAM

2000 ◽  
Author(s):  
Jack Lee ◽  
Kuo-Hui Huang ◽  
Jen-Lang Lue
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cross Section ◽  
Three Dimensional ◽  
Top Down ◽  
Deep Trench ◽  
Etching Solution ◽  
Transmission Electron ◽  
Novel Method ◽  
Scanning Electron

Abstract A novel method has been developed to reveal the entire three dimensional (3D) deep trench (DT) capacitors for inspection in DRAM, especially NO capacitor dielectrics, ASG residues at corners, morphology etc., for process evaluation and failure analysis. It offers an alternative to conventional cross-section polishing, top down polishing or FIB milling methods. A DRAM chip was ground and polished down to a certain level from the chip backside. An etching solution was then applied to enhance the DTs appearance. 3D DTs can be inspected in scanning electron microscopy (SEM). The entire DTs or specific DT also can be lifted out for detailed investigation in transmission electron microscopy (TEM). The innovation of this technique is to provide a quick 3D observation in SEM, and much more flexibility to an entire DT inspection in TEM, which were not presented before.

scholarly journals Three-dimensional Monte Carlo simulations of the dynamics of macromolecular particles in solutions flowing in mesopores

2010 ◽  
Vol 8 (5) ◽  
pp. 1009-1013 ◽  
Author(s):  
Ali Atwi ◽  
Antoine Khater ◽  
Abbas Hijazi
Keyword(s):  
Monte Carlo ◽  
Probability Distribution ◽  
Numerical Simulations ◽  
Solid Surface ◽  
Dynamic Equilibrium ◽  
Three Dimensional ◽  
Distribution Functions ◽  
Depletion Layer ◽  
Probability Distribution Functions ◽  
Equilibrium Probability

AbstractNumerical simulations are developed to calculate the dynamic equilibrium probability distribution functions (PDF) for macromolecular rod-like particles suspended in a fluid under hydrodynamic flow inside mesopores. The simulations take into account the effects of Brownian and hydrodynamic forces acting on the particles, as well as diffusive collisions of the particles with the solid surface boundaries. An algorithm is developed for this purpose based on Jeffery’s equations for the dynamics of ellipsoidal objects in bulk fluids, and on a mechanism of restitution for the diffusive collisions. The results are presented with a focus on the depletion layer next to two types of solid boundaries, ideally flat and rough. They demonstrate the significance of numerical simulations in 3D compared to previous results based on a 2D approach. In particular, we are able to obtain a complete topography for the PDFs segmented as a hierarchy in the depletion layer.

scholarly journals Three-dimensional mitochondrial arrangement in ventricular myocytes: from chaos to order

2006 ◽  
Vol 291 (6) ◽  
pp. C1148-C1158 ◽  
Author(s):  
Rikke Birkedal ◽  
Holly A. Shiels ◽  
Marko Vendelin
Keyword(s):  
Ventricular Myocytes ◽  
Quantitative Description ◽  
Three Dimensional ◽  
Distribution Functions ◽  
Three Dimensions ◽  
Organizational Changes ◽  
Adult Rat ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
Confocal Images ◽  
Novel Method

We have developed a novel method to quantitatively analyze mitochondrial positioning in three dimensions. Using this method, we compared the relative positioning of mitochondria in adult rat and rainbow trout ( Oncorhynchus mykiss) ventricular myocytes. Energetic data suggest that trout, in contrast to the rat, have two subpopulations of mitochondria in their cardiomyocytes. Therefore, we speculated whether trout cardiomyocytes exhibit two types of mitochondrial patterns. Stacks of confocal images of mitochondria were acquired in live cardiomyocytes. The images were processed and mitochondrial centers were detected automatically. The mitochondrial arrangement was analyzed by calculating the three-dimensional probability density and distribution functions describing the distances between neighboring mitochondrial centers. In the rat (8 cells with a total of 7,546 mitochondrial centers), intermyofibrillar mitochondria are highly ordered and arranged in parallel strands. These strands are separated by ∼1.8 μm and can be found in any transversal direction relative to each other. Neighboring strands exhibit the same mitochondrial periodicity. In contrast to the rat, trout ventricular myocytes (22 cells; 5,528 mitochondrial centers) exhibit a relatively chaotic mitochondrial pattern. Neighboring mitochondria can be found in any direction relative to each other. Thus, two potential subpopulations of mitochondria in trout are not distinguishable by their pattern. The developed method required minor interaction in the filtering of the mitochondrial centers. It is therefore a practical approach to describe intracellular organization and may also be used for analysis of time-dependent organizational changes. The obtained quantitative description of mitochondrial organization is a requisite for accurate mathematical analysis of mitochondrial systems biology.

scholarly journals Information Geometric Investigation of Solutions to the Fractional Fokker–Planck Equation

Mathematics ◽  
2020 ◽  
Vol 8 (5) ◽  
pp. 668
Author(s):  
Johan Anderson
Keyword(s):  
Probability Distribution ◽  
Numerical Solutions ◽  
Planck Equation ◽  
Langevin Dynamics ◽  
Distribution Functions ◽  
Anomalous Transport ◽  
Time Dependent ◽  
Probability Distribution Functions ◽  
Novel Method ◽  
Fokker Planck

A novel method for measuring distances between statistical states as represented by probability distribution functions (PDF) has been proposed, namely the information length. The information length enables the computation of the total number of statistically different states that a system evolves through in time. Anomalous transport can presumably be modeled fractional velocity derivatives and Langevin dynamics in a Fractional Fokker–Planck (FFP) approach. The numerical solutions or PDFs are found for varying degree of fractionality ( α ) of the stable Lévy distribution as solutions to the FFP equation. Specifically, the information length of time-dependent PDFs for a given fractional index α is computed.

scholarly journals Study of Meltblown Structures Formed by Robotic and Meltblowing Integrated System: Impact of Process Parameters on Fiber Orientation

2002 ◽  
Vol os-11 (4) ◽  
pp. 1558925002OS-01
Author(s):  
Raoul Farer ◽  
Tushar K. Ghosh ◽  
Abdelfattah M. Seyam ◽  
Eddie Grant ◽  
Subhash K. Batra
Keyword(s):  
Fiber Orientation ◽  
Three Dimensional ◽  
Orientation Distribution ◽  
Distribution Functions ◽  
Integrated System ◽  
Rotating Drum ◽  
Throughput Rate ◽  
Approach Angle ◽  
Fiber Orientation Distribution ◽  
Parametric Studies

A novel system that forms two-dimensional (2D) structures on a rotating drum and three-dimensional (3D) structures on 3D molds through proper integration of a laboratory scale meltblown unit with a small die and six-axis robot is briefly described. The system advantages over traditional systems are demonstrated. Parametric studies evaluating the effect of take-up speed, die-to-collector-distance (DCD), polymer throughput rate, and attenuating air pressure on the fiber orientation distribution functions (ODFs) of 2D structures formed by the system are reported. An additional new parameter termed “fiber-stream approach-angle” is introduced and its impact on the ODF of 2D structures is also reported. Under the experimental range studied, the ODFs were significantly impacted by the parameters studied. The fiber-stream approach angle showed the highest impact, among the parameter studied, on the ODF.

Three-Dimensional Reconstruction Using Stereo Pairs from Serial Thick Sections

1977 ◽  
Vol 35 ◽  
pp. 562-563
Author(s):  
Robert Glaeser ◽  
Thomas Bauer ◽  
David Grano
Keyword(s):  
Three Dimensional ◽  
Dimensional Structure ◽  
Serial Sections ◽  
Thin Sections ◽  
3 Dimensional ◽  
Transmission Electron ◽  
Freeze Dried ◽  
Dimensional Reconstruction ◽  
Stereo Imagery ◽  
Whole Mounts

In transmission electron microscopy, the 3-dimensional structure of an object is usually obtained in one of two ways. For objects which can be included in one specimen, as for example with elements included in freeze- dried whole mounts and examined with a high voltage microscope, stereo pairs can be obtained which exhibit the 3-D structure of the element. For objects which can not be included in one specimen, the 3-D shape is obtained by reconstruction from serial sections. However, without stereo imagery, only detail which remains constant within the thickness of the section can be used in the reconstruction; consequently, the choice is between a low resolution reconstruction using a few thick sections and a better resolution reconstruction using many thin sections, generally a tedious chore. This paper describes an approach to 3-D reconstruction which uses stereo images of serial thick sections to reconstruct an object including detail which changes within the depth of an individual thick section.

Effect of Contraceptive Steroids on the Endometrium of Guinea Pig: SEM study

1977 ◽  
Vol 35 ◽  
pp. 668-669
Author(s):  
Mai M. Said ◽  
Ramesh K. Nayak ◽  
Randall E. McCoy
Keyword(s):  
Guinea Pig ◽  
Reproductive Tract ◽  
Three Dimensional ◽  
Female Reproductive Tract ◽  
Human Female ◽  
Surface Ultrastructure ◽  
Transmission Electron ◽  
Sem Study ◽  
Uterine Mucosa ◽  
Group 1

Burgos and Wislocki described changes in the mucosa of the guinea pig uterus, cervix and vagina during the estrous cycle investigated by transmission electron microscopy. More recently, Moghissi and Reame reported the effects of progestational agents on the human female reproductive tract. They found drooping and shortening of cilia in norgestrel and norethindrone- treated endometria. To the best of our knowledge, no studies concerning the effects of mestranol and norethindrone given concurrently on the three-dimensional surface features on the uterine mucosa of the guinea pig have been reported. The purpose of this study was to determine the effect of mestranol and norethindrone on surface ultrastructure of guinea pig uterus by SEM.Seventy eight animals were used in this study. They were allocated into two groups. Group 1 (20 animals) was injected intramuscularly 0.1 ml vegetable oil and served as controls.

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