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Displaying 176 - 200 of 1719

Moisture Uptake Characterization in Nanocellulose Using Microwave Cavity

August 17, 2017
Author(s)
Caglar Emiroglu, Bharath N. Natarajan, Jeffrey W. Gilman, James Alexander Liddle, Jan Obrzut
Cellulose nanocrystal films with different helical modulation lengths are characterized. Films are obtained by tuning the rate of evaporation and surface functionalization. Dielectric constant measurements are performed and the water confinement is

Surface interaction parameter measurement of solvated polymers via model end-tethered chains

August 11, 2017
Author(s)
Richard J. Sheridan, Sara V. Orski, Ronald L. Jones, Sushil K. Satija, Kathryn L. Beers
We present a method for the direct measurement of the relative energy of interaction between a solvated polymer and a solid interface. By tethering linear chains covalently to the surface, we ensured the idealized and constant configuration of polymer

Raman Identification of Multiple Melting Peaks of Polyethylene

August 1, 2017
Author(s)
Ying Jin, Anthony P. Kotula, Chad R. Snyder, Angela R. Hight Walker, Kalman D. Migler, Young J. Lee
Multiple melting peaks of high-density polyethylene produced by complex thermal pre-treatment are investigated with variable temperature Raman spectroscopy and differential scanning calorimetry (DSC). We examine the origin of the observed multiple melting

Fast-Responding Bio-Based Shape Memory Thermoplastic Polyurethanes

July 14, 2017
Author(s)
Zoran S. Petrovic, Jelena Milic, Fan Zhang, Jan Ilavsky
Fast response shape-memory polyurethanes were prepared from bio-based polyols, diphenyl methane diisocyanate and butane diol. The bio-based polyester polyols were synthesized from 9-hydroxynonanoic acid, a product obtained by ozonolysis of fatty acids

Universal Interrelation Between Measures of Particle and Polymer Size

July 6, 2017
Author(s)
Luis F. Vargas Lara, Marc L. Mansfield, Jack F. Douglas
The characterization of many objects often involves the determination of a basic set of particle size measures derived mainly from scattering and transport property measurements. For polymers, these basic properties often include the radius of gyration Rg

Rheology of ballistic clay: the effect of temperature and shear history

May 9, 2017
Author(s)
Ran Tao, Kirk D. Rice, Aaron M. Forster
Ballistic clay is used as a backing material for standards-based ballistic resistance tests for the purposes of providing a measure of the energy transferred to the body when a threat is defeated. However, this material exhibits complex thermomechanical

Dielectric Characterization of Confined Water in Chiral Cellulose Nanocrystal Films

April 10, 2017
Author(s)
Bharath N. Natarajan, Caglar Emiroglu, Jan Obrzut, Douglas M. Fox, Beatriz Pazmino, Jack F. Douglas, Jeffrey W. Gilman
A known deterrent to a large scale development and use of cellulose nanocrystals (CNCs) is their affinity for moisture, which has a profound effect on dispersion, wetting, interfacial adhesion, matrix crystallization and water uptake. To quantify the

Light-stimulated Permanent Shape Reconfiguration in Crosslinked Polymer Microparticles

April 7, 2017
Author(s)
Lewis M. Cox, Xiaohao Sun, Chen Wang, Nancy Sowan, Jason Killgore, Rong Long, Hengan Wu, Christopher N. Bowman, Yifu Ding
Covalent adaptable networks (CANs) are cross-linked polymer networks capable reconfiguring their network topology, enabling stress relaxation and shape changing behaviors. Reversible addition-fragmentation chain transfer (RAFT) is one specific mechanism by

Label-free hyperspectral dark-field microscopy towards quantitative scatter imaging

March 27, 2017
Author(s)
Philip Cheney, David McClatchy III, Stephen Kanick, Paul Lemaillet, David W. Allen, Daniel Samarov, Brian Pogue, Jeeseong C. Hwang
A hyperspectral dark-field microscopy technique has been developed for imaging spatially distributed diffuse reflectance spectra from light-scattering samples. In this report, quantitative scatter spectroscopy was demonstrated with a uniform scattering

Polydimethylsiloxane tissue-mimicking phantoms for quantitative optical medical imaging standards

March 24, 2017
Author(s)
Jeeseong Hwang, Hyun J. Kim, Paul Lemaillet, Dirk Grosenick, Thomas Gladytz, David McClatchy III, Kimberly A. Briggman, Brian Pogue
We report on a procedure to build and characterize solid tissue-mimicking phantoms of polydimethylsiloxane (PDMS) polymers. Controlled inclusion of light scattering titanium dioxide (TiO2) nanoparticles enables the creation of phantoms having tunable light

A Combinatorial Study of Metal Gate/HfO2-MOSCAPS

February 19, 2017
Author(s)
Martin L. Green, Kao-Shuo Chang, Ichiro Takeuchi, T Chikyow
Combinatorial methodology is a rapid technique for surveying new gate dielectrics and gate metal electrodes for the very complex advanced CMOS gate stack. Here, we report on a typical metal gate electrode alloy system, the Ni-Ti-Pt ternary. We have

A Re-Examination of a Specific Surface Area Research Material

February 19, 2017
Author(s)
Dennis B. Minor
Specific surface area(SSA) analysis is one of the most common, quick, and inexpensive techniques used in analytical laboratories to characterize a variety of solid materials using a variety of gases. The technique is not labor intensive, can yield results

Abrasive Machining of Glass-Infiltrated Alumina with Diamond Burs

February 19, 2017
Author(s)
L Yin, L K. Ives, S Jahanmir, E D. Rekow, E Romberg
The abrasive machining characteristics of a glass-infiltrated dry-pressed alumina used for fabrication of all-ceramic dental crowns are investigated using a high-speed dental handpiece and diamond burs containing supercoarse (180 m), fine (40 m), and

ACerS-NIST Phase Equilibria Diagrams Volume XIV Oxides

February 19, 2017
Author(s)
Robert S. Roth, Terrell A. Vanderah
This volume is the fourteenth of the topically-oriented series of phase diagram compilations and the tenth to appear since the National Institute of Standards (NIST) and the American Ceramic Society (ACerS) embarked on a jointly-sponsored expanded Ceramic

An Exception to Amontons' Law: The Friction of Carbon Surfaces in Air

February 19, 2017
Author(s)
P M. McGuiggan
The friction of carbon has been of much interest in recent years due to its good tribological properties. These properties include high wear resistance, high hardness, low friction coefficients, and low corrosion. 1 In computer hard disks, the magnetic

Angular-Momentum Resolved Partial Density of States of Rutile TiO 2 : Theory and Experiment

February 19, 2017
Author(s)
Joseph Woicik, E J. Nelson, L Kronik, M Jain, J R. Chelikowsky, D Heskett, L E. Berman, G S. Herman
Using the method of site-specific valence x-ray photoelectron spectroscopy (SSVKPS), we have experimentally determined the Ti and O partial density of occupied valence states of rutile TiO2. Excellent agreement with ab initio local density approximation

Anomalous Lattice Expansion of Coherently Strained SrTiO 3 Thin Films Grown on Si(001) by Kinetically Controlled Sequential Deposition

February 19, 2017
Author(s)
Joseph Woicik, H Li, P Zschack, E Karapetrova, P Ryan, C R. Ashman, C S. Hellberg
X-ray diffraction has been used to study the epitaxy and lattice expansion of SrTiO3 thin films grown on Si(001) by kinetically controlled sequential deposition (KCSD). Unlike films grown by traditional molecular beam epitaxy (MBE), these films have an in

Applications of Ceramics for Healthcare: The Future Has Begun

February 19, 2017
Author(s)
Grady S. White
Dramatic improvements in our understanding of how biological systems work, diseases initiate, and illnesses progress have given rise to the expectation that many of these ailments can be cured, perhaps even in their precursor states, as new tools are
Displaying 176 - 200 of 1719