TRANSPORT PHENOMENA IN PERCOLATING STRUCTURES: A KEY FOR THE ANALYSIS AND REINTERPRETATION OF SOME PRACTICAL MODELING PROBLEMS

The percolating morphology is adopted as a reference conceptualization to evaluate the “fractality” effect on the transport phenomena in disordered systems. The relevance of this approach is demonstrated using two practical case studies: conducting polymers and porous media. In the first case, a conceptual model for conducting polymers is proposed in terms of a random resistor network subjected to percolation disorder. The effect of topological and morphological disorder on the conducting behavior of an idealized system is investigated and some insights, are given as to the way in which conducting polymers could be designed. In the second case, the examination of effective transport properties in percolation-like porous structures enables us to reinterpret the classical guidelines for the characterization of fluid flow through porous beds.

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In vivo and in vitro characterization of immediate release dosage forms containing n-acetylcysteine using the dynamic open flow-through test apparatus

10.26226/morressier.57d6b2b7d462b8028d88dd29 ◽

2016 ◽

Author(s):

Maximilian Sager

Keyword(s):

Immediate Release ◽

Dosage Forms ◽

Test Apparatus ◽

Open Flow ◽

In Vitro Characterization ◽

Flow Through

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Physical Failure Analysis Techniques for Front-End-of-Line Defect Analysis

ISTFA 2016: Conference Proceedings from the 42nd International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2016p0182 ◽

2016 ◽

Author(s):

Dirk Doyle ◽

Lawrence Benedict ◽

Fritz Christian Awitan

Keyword(s):

Cross Section ◽

Focused Ion Beam ◽

Ion Beam ◽

Gate Oxide ◽

Top Down ◽

New Techniques ◽

First Case ◽

Transmission Electron ◽

Scanning Transmission

Abstract Novel techniques to expose substrate-level defects are presented in this paper. New techniques such as inter-layer dielectric (ILD) thinning, high keV imaging, and XeF2 poly etch overflow are introduced. We describe these techniques as applied to two different defects types at FEOL. In the first case, by using ILD thinning and high keV imaging, coupled with focused ion beam (FIB) cross section and scanning transmission electron microscopy (STEM,) we were able to judge where to sample for TEM from a top down perspective while simultaneously providing the top down images giving both perspectives on the same sample. In the second case we show retention of the poly Si short after removal of CoSi2 formation on poly. Removal of the CoSi2 exposes the poly Si such that we can utilize XeF2 to remove poly without damaging gate oxide to reveal pinhole defects in the gate oxide. Overall, using these techniques have led to 1) increased chances of successfully finding the defects, 2) better characterization of the defects by having a planar view perspective and 3) reduced time in localizing defects compared to performing cross section alone.

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Polymer Chemistry

10.1093/oso/9780198503095.001.0001 ◽

2004 ◽

Keyword(s):

Conducting Polymers ◽

Liquid Crystalline ◽

Polymer Chemistry ◽

Chain Growth ◽

Crystalline Polymers ◽

Wide Range ◽

Cyclic Oligomers ◽

Step Growth

Polymer Chemistry: A Practical Approach in Chemistry has been designed for both chemists working in and new to the area of polymer synthesis. It contains detailed instructions for preparation of a wide-range of polymers by a wide variety of different techniques, and describes how this synthetic methodology can be applied to the development of new materials. It includes details of well-established techniques, e.g. chain-growth or step-growth processes together with more up-to-date examples using methods such as atom-transfer radical polymerization. Less well-known procedures are also included, e.g. electrochemical synthesis of conducting polymers and the preparation of liquid crystalline elastomers with highly ordered structures. Other topics covered include general polymerization methodology, controlled/"living" polymerization methods, the formation of cyclic oligomers during step-growth polymerization, the synthesis of conducting polymers based on heterocyclic compounds, dendrimers, the preparation of imprinted polymers and liquid crystalline polymers. The main bulk of the text is preceded by an introductory chapter detailing some of the techniques available to the scientist for the characterization of polymers, both in terms of their chemical composition and in terms of their properties as materials. The book is intended not only for the specialist in polymer chemistry, but also for the organic chemist with little experience who requires a practical introduction to the field.

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First case of Kingella kingae spondylodiscitis in an elderly man with a molecular characterization of the responsible strain

Infectious Diseases Now ◽

10.1016/j.idnow.2020.10.003 ◽

2021 ◽

Author(s):

Marie Doussiere ◽

Morgane Choquet ◽

Franck Grados ◽

François Peltier ◽

Jean-Philippe Lanoix ◽

...

Keyword(s):

Molecular Characterization ◽

Kingella Kingae ◽

First Case

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Crystalline shielding mitigates structural rearrangement and localizes memory in jammed systems under oscillatory shear

Science Advances ◽

10.1126/sciadv.abe3392 ◽

2021 ◽

Vol 7 (20) ◽

pp. eabe3392

Author(s):

Erin G. Teich ◽

K. Lawrence Galloway ◽

Paulo E. Arratia ◽

Danielle S. Bassett

Keyword(s):

Local Structure ◽

Disordered Systems ◽

Amorphous Materials ◽

Structural Rearrangement ◽

Oscillatory Shear ◽

Disordered Materials ◽

Rheological Measurements ◽

Particle Level ◽

Individual Particles

The nature of yield in amorphous materials under stress has yet to be fully elucidated. In particular, understanding how microscopic rearrangement gives rise to macroscopic structural and rheological signatures in disordered systems is vital for the prediction and characterization of yield and the study of how memory is stored in disordered materials. Here, we investigate the evolution of local structural homogeneity on an individual particle level in amorphous jammed two-dimensional (athermal) systems under oscillatory shear and relate this evolution to rearrangement, memory, and macroscale rheological measurements. We define the structural metric crystalline shielding, and show that it is predictive of rearrangement propensity and structural volatility of individual particles under shear. We use this metric to identify localized regions of the system in which the material’s memory of its preparation is preserved. Our results contribute to a growing understanding of how local structure relates to dynamic response and memory in disordered systems.

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Spectral Decomposition of the Flow and Characterization of the Sound Signals through Stenoses with Different Levels of Severity

Bioengineering ◽

10.3390/bioengineering8030041 ◽

2021 ◽

Vol 8 (3) ◽

pp. 41

Author(s):

Fardin Khalili ◽

Peshala T. Gamage ◽

Amirtahà Taebi ◽

Mark E. Johnson ◽

Randal B. Roberts ◽

...

Keyword(s):

Pressure Fluctuations ◽

High Energy ◽

Sound Sources ◽

Severity Level ◽

Non Invasive ◽

Flow Through ◽

Severity Of The Disease ◽

Proper Orthogonal ◽

Different Levels

Treatments of atherosclerosis depend on the severity of the disease at the diagnosis time. Non-invasive diagnosis techniques, capable of detecting stenosis at early stages, are essential to reduce associated costs and mortality rates. We used computational fluid dynamics and acoustics analysis to extensively investigate the sound sources arising from high-turbulent fluctuating flow through stenosis. The frequency spectral analysis and proper orthogonal decomposition unveiled the frequency contents of the fluctuations for different severities and decomposed the flow into several frequency bandwidths. Results showed that high-intensity turbulent pressure fluctuations appeared inside the stenosis for severities above 70%, concentrated at plaque surface, and immediately in the post-stenotic region. Analysis of these fluctuations with the progression of the stenosis indicated that (a) there was a distinct break frequency for each severity level, ranging from 40 to 230 Hz, (b) acoustic spatial-frequency maps demonstrated the variation of the frequency content with respect to the distance from the stenosis, and (c) high-energy, high-frequency fluctuations existed inside the stenosis only for severe cases. This information can be essential for predicting the severity level of progressive stenosis, comprehending the nature of the sound sources, and determining the location of the stenosis with respect to the point of measurements.

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Characterization of the water flow through concrete based on parameter estimation from infiltration tests

Cement and Concrete Research ◽

10.1016/j.cemconres.2005.11.015 ◽

2006 ◽

Vol 36 (9) ◽

pp. 1575-1582 ◽

Cited By ~ 9

Author(s):

Vicente Navarro ◽

Ángel Yustres ◽

Luís Cea ◽

Miguel Candel ◽

Ricardo Juncosa ◽

...

Keyword(s):

Parameter Estimation ◽

Water Flow ◽

Flow Through ◽

Infiltration Tests

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B.05 Hemi-laryngopharyngeal spasm (HELPS) syndrome: The discovery, cure, and characterization of a new neurological condition

Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques ◽

10.1017/cjn.2017.76 ◽

2017 ◽

Vol 44 (S2) ◽

pp. S11-S11

Author(s):

C Honey ◽

M Morrison

Keyword(s):

Surgical Care ◽

Review Of The Literature ◽

The Past ◽

First Case ◽

Patient Reported ◽

Operative Outcome ◽

Small Cohort ◽

The Common ◽

Similar Motor

Background: We published the world’s first case of hemi-laryngpharyngeal spasm (HELPS) syndrome cured by microvascular decompression (MVD) of the Xth cranial nerve in 2016. We now present a small cohort of patients (n=3) successfully treated with surgery in order to better delineate the common characteristics of this syndrome, diagnostic tests of choice, nuances of their surgical care and outcomes of their treatment. Methods: The history and physical examination of three patients with HELPS syndrome are presented. Pre-operative laryngoscopy, neuroimaging, response to botox and intra-operative videos are detailed. Post-operative outcome and complications are presented. Results: Each patient reported similar motor (choking) and sensory (coughing) features in their history. Episodic choking relentlessly progressed over the years until it occurred while sleeping and with frightening severity prompting tracheostomy in one patient and intubation in another. A “tickling” sensation deep in the throat triggered episodic coughing that worsened over the years until it occurred while sleeping and with frightening severity (syncope and incontinence). Conclusions: A review of the literature suggests that patients with similar symptoms, often called episodic laryngospasm in the past, have been treated with psychotherapy or antacids. With the recognition that a clearly defined subset of these patients have HELPS syndrome, we can offer them the potential of a neurosurgical cure.

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