U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications

NIST Authors in Bold

Displaying 751 - 775 of 2122

Molecular Sieving of Ethylene from Ethane using a Rigid Metal-Organic Framework

November 26, 2018
Author(s)
Rui-Biao Lin, Libo Li, Hao-Long Zhou, Hui Wu, Chaohui He, Shun Li, Rajamani Krishna, Jinping Li, Wei Zhou, Banglin Chen
There are great challenges in developing efficient adsorbents to replace currently used and energy-intensive cryogenic distillation processes for olefin/paraffin separations, due to the similar physical properties of the two molecules. We report an

Analysis of Small Angle Neutron Scattering Spectra from Deformed Polymers with Spherical Harmonic Expansion Method and a Network Model

November 13, 2018
Author(s)
Zhi-Yuan Wang, Dejia Kong, Lincan Yang, Hongwei Ma, Fengmei Su, Kanae N. Ito, Yun Liu, Xuewu Wang, Zhe Wang
In this paper, we combine the recently proposed spherical harmonic expansion (SHE) method [Phys. Rev. X 2017, 7, 031003] with a modified network model to analyze the small-angle neutron scattering (SANS) spectra from deformed entangled polymers. Focusing

Hierarchically Patterned Elastomeric and Thermoplastic Polymer Films through Nanoimprinting and Ultraviolet Light Exposure

November 13, 2018
Author(s)
Jack F. Douglas, Ying Chen, Manish Kulkarni, Allan Marshall, Alamgir Karim, ZiLu Wang, Xiaoteng Wang, Abdullah Al-Enizi, Ahmed Elzatahry, Andrey V. Dobrynin
We develop a simple and generally applicable method to fabricate hierarchical interfacial patterns in elastomer and thermoplastic polymer films through a combination of nanoimprinting and UVO microlithography. Using this method, tunable and hierarchically

Thermal Pulse for Rapid Surface Processing of Solid-State Electrolytes

November 10, 2018
Author(s)
Chengwei Wang, Hua Xie, Weiwei Ping, Jiaqi Dai, Jamie Weaver, Guolin Feng, Yonggang Yao, Shuaiming He, Howard Wang, Karen Gaskell, Liangbing Hu
Surface contamination and degradation are two main issues leading to performance decay of ceramic-based solid-state electrolytes (SSEs). The typical strategies used to clean surface contaminants and restore ceramic materials involve mechanical polishing or

Control of polarity in multilayer MoTe2 field-effect transistors by channel thickness

November 9, 2018
Author(s)
Albert Davydov, Mona Zaghloul, Sergiy Krylyuk, Ratan K. Debnath, Asha Rani, Kyle J. DiCamillo, Payam Taheri
In this study, electronic properties of field-effect transistors (FETs) fabricated from exfoliated MoTe2 single crystals are investigated as a function of channel thickness. The conductivity type in FETs gradually changes from n-type for thick MoTe2 layers

A Metal?Organic Framework with Suitable Pore Size and Specific Functional Site for the Removal of Trace Propyne from Propylene

November 7, 2018
Author(s)
Libo Li, Hui-Min Wen, Chaohui He, Rui-Biao Lin, Rajamani Krishna, Hui Wu, Wei Zhou, Jinping Li, Banglin Chen
Removal of trace propylene (C 3H 4) from propylene/propyne (C 3H 4/C 3H 6) mixtures is more complicated and challenging than that of acetylene/ethylene (C 2H 2/C 2H 4) in view of their closer molecular sizes and physical properties. Research on C 3H 4C 3H

Tuning the Relaxation of Nano-Patterned Polymer Films with Polymer-Grafted Nanoparticles: Observation of Entropy-Enthalpy Compensation

November 6, 2018
Author(s)
Sonal Bhadauriya, Xiaoteng Wang, Jack F. Douglas, Praveen Pitliya, Jianan Zhang, Dharmaraj Raghavan, Michael R. Bockstaller, Christopher Stafford, Alamgir Karim
Polymer films provide a versatile "plastic" material in which complex functional relief patterns can be imprinted with a resolution down to tens of nanometers. However, the utility of such patterned materials is limited by the tendency of imprinted

Tuning the Relaxation of Nanopatterned Polymer Films with Polymer-Grafted Nanoparticles: Observation of Entropy–Enthalpy Compensation

November 6, 2018
Author(s)
Jack F. Douglas, Xiaoteng Wang, Sonal Bhadauriya, Ren Zhang, Praveen Pitliya, Dharmaraj Raghavan, Alamgir Karim
We show that the previously observed polymeric clustering of nanoparticles (NPs) with grafted chains within polymer matrices can be pattern-directed by nanoimprinting ultrathin nanocomposite films so that the NPs segregate to thicker film regions where

Chemical Selection of Emission State Configuration in a Quantum Light Emitter

November 1, 2018
Author(s)
Ming Zheng, Geyou Ao, Stephen K. Doorn
Covalently-introduced photoluminescent sp3 defects generate new emitting states and dramatically expand optical functionality of single-wall carbon nanotubes, opening routes to enhanced imaging, photon upconversion, and room-temperature single photon

Compositional Imaging and Analysis of Late Iron Age Glass from the Broborg Vitrified Hillfort, Sweden

October 31, 2018
Author(s)
Jamie Weaver, Scott A. Wight, Carolyn Pearce, John McCloy, Thomas Lam, Rolf Sjoblom, David Peeler, Michael Schweiger, Albert Kruger, Scott Whittaker, Edward Vicenzi
Numerous Iron Age hillforts were constructed throughout Europe on high ground to serve ancient settlements. The edifice walls of a small fraction of hillforts were vitrified as a result of high temperature activity, most likely to reinforce the walls

Ethane/Ethylene Separation in a Metal-Organic Framework with Iron-Peroxo Sites

October 26, 2018
Author(s)
Libo Li, Rui-Biao Lin, Rajamani Krishna, Hao Li, Shengchang Xiang, Hui Wu, Jinping Li, Wei Zhou, Banglin Chen
The separation of ethane from its corresponding ethylene is a very important challenging and energy-intensive process in the chemical industry. Herein we report a microporous metal-organic framework Fe 2(O 2)(dobdc) (dobdc 4-: 2,5-dioxido-1,4

Flow fluctuations in wormlike micelle fluids

October 22, 2018
Author(s)
Paul NMN Salipante, Steven Meek, Steven D Hudson
We investigate the unstable flow of wormlike micelle solutions in pressure driven capillary flow, with a focus on the effect of entrance geometry on the fluid fluctuations. The flow is measured at different points in the capillary using particle image

Long-Range Electric Field Control of Permalloy Layers in Strain-Coupled Composite Multiferroics

October 18, 2018
Author(s)
Michelle E. Jamer, Colin R. Rementer, Anthony Barra, Alexander Grutter, Kevin Fitzell, Daniel Gopman, Julie Borchers, Gregory P. Carman, Brian Kirby, Jane P. Chang
Artificial composite multiferroic materials can be created by interfacing magnetostrictive and piezoelectric materials, allowing for electric field control of magnetic properties. For multilayer device applications, addition of weakly magnetostrictive

Boosting Ethane/Ethylene Separation within Isoreticular Ultramicroporous Metal-Organic Frameworks

October 11, 2018
Author(s)
Rui-Biao Lin, Hui Wu, Libo Li, Xiao-Liang Tang, Zhiqiang Li, Junkuo Gao, Hui Cui, Wei Zhou, Banglin Chen
The separation of ethane from its analogous ethylene is of great importance in the petrochemical industry, but very challenging and energy-intensive. Adsorptive separation using C cH 6-selective porous materials can directly produce high purity C 2H 4 in a

reductus: A Stateless Python Data-Reduction Service with a Browser Frontend

October 1, 2018
Author(s)
Brian B. Maranville, William D. Ratcliff, Paul A. Kienzle
The online data reduction service reductus transforms measurements in experimental science from laboratory coordinates into physically meaningful quantities with accurate estimation of uncertainties based on instrumental settings and properties. This

Microscopic Identification of Micro-Organisms on Pre-Viking Swedish Hillfort Glass

September 30, 2018
Author(s)
Bruce Arey, Edward Vicenzi, Rolf Sjoblom, Robert Koestler, Paula DePriest, Thomas Lam, David Peeler, John McCloy, Albert Kruger, Jamie Weaver
Borborg Hillfort is a vitrified hillfort located in the Husby-Långhundra parish in Uppland Sweden (Fig. 1A). The site dates to the Great Migration Period, around 740 ± 100 CE. [1]. Two types of glasses have been identified within the ramparts – one that is

Reversible Flat to Rippling Phase Transition in Fe Containing Layered Battery Electrode Materials

September 26, 2018
Author(s)
Xi Chen, Sooyeon Hwang, Robin Chisnell, Yichao Wang, Fan Wu, Sooran Kim, Jeffrey W. Lynn, Dong Su, Xin Li
The Jahn-Teller effect in solid-state chemistry relates the symmetry of electronic configuration to the atomic arrangement around the individual transition metal ion. The collective behavior of many such Jahn-Teller active entities is of great interest in

Approaches for the Quantitative Analysis of Oxidation State in Cerium Oxide Nanomaterials

September 21, 2018
Author(s)
Christopher M. Sims, Russell A. Maier, Aaron C. Johnston-Peck, Justin M. Gorham, Vincent A. Hackley, Bryant C. Nelson
Cerium oxide nanomaterials (nanoceria, CNMs) are receiving increased attention from the research community due to their unique chemical properties, most prominent of which is their ability to alternate between the Ce3+ and Ce4+ oxidation states. While many

Natural Alteration of 6Li Neutron Shielding Glass

September 21, 2018
Author(s)
Jamie L. Weaver, Danyal J. Turkoglu
Li-6 alumino-silicate glass, a neutron shielding material, has been studied to determine if and to what extent it alters under natural conditions. Analyses included neutron depth profiling, prompt gamma activation analysis, x-ray diffraction, and scanning

On the mechanisms and the characterization of the pulsed electron grafting of styrene onto poly(tetrafluoroethylene-co-hexafluoropropylene) to synthesize a polymer electrolyte membrane

September 21, 2018
Author(s)
Byung N. Kim, Alia Weaver, Marina Chumakov, Ileana M. Pazos, Dianne L. Poster, Karen Gaskell, Do H. Han, Gunther Scherer, Michael A. Yandrasits, Byung C. Lee, Mohamad Al-Sheikhly
During the pulsed-electron beam direct grafting of neat styrene onto poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) substrate, the radiolytically-produced styryl and carbon-centered FEP radicals undergo various desired and undesired competing

Structure, Rheology, and Microrheology of Wormlike Micelles made of PB-PEO Diblock Copolymers

September 21, 2018
Author(s)
Antonio Tavera-Vazquez, Brisa Arenas-Gomez, Cristina Garza, Yun Liu, Rolando Castillo
A diblock copolymer made of poly(but-2-ene-1,4-diyl)-block-poly(oxyethylene), with a degree of polymerization of the polybutadiene and polyethylene blocks of 37 and 57, respectively, self-assembles in water as worm-like micelles determined with small angle
Displaying 751 - 775 of 2122