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.

Chemistry

Analytical chemistry

Search Publications

Search Title, Abstract, Conference, Citation, Keyword or Author
  • Published Date
Displaying 1301 - 1325 of 2094

The Calculation of Natural Gas Viscosity

August 14, 2009
Author(s)
Aaron N. Johnson, William Johansen
The calculation of natural gas viscosity has been implemented many different ways including the use of constants. Different methods of calculating natural gas viscosity may produce values with differences as large as 50%. Increasing natural gas prices

Formation of Silicon-Based Molecular Electronic Structures Using Flip-chip Lamination

August 11, 2009
Author(s)
Mariona Coll Bau, Lauren H. Miller, Lee J. Richter, Daniel R. Hines, Curt A. Richter, Christina A. Hacker
The use of organic molecules to impart electrical surface properties has been a subject of intense research not only from a fundamental perspective but for many technological applications. In particular, organic molecules have been proposed as active

Reference measurements of Hydrogen's Dielectric Permittivity

August 10, 2009
Author(s)
James W. Schmidt, Michael R. Moldover, Eric F. May
We used a quasi-spherical cavity resonator to measure the relative dielectric permittivity ε r of H 2 at frequencies from 2.4 GHz to 7.3 GHz, at pressures up to 6.5 MPa, and at the temperatures 273 K and 293 K. The resonator was calibrated using auxiliary

High Definition Flow

August 1, 2009
Author(s)
John D. Wright, Michael R. Moldover
From pharmaceutical production to the natural gas market, exact flow measurements are critical. Here's how NIST helps keep us all on the same page.

Purity determination as needed for the realisation of primary standards for elemental determination - status of international comparability

July 9, 2009
Author(s)
Gregory C. Turk, Heinrich Kipphardt, Ralf Matschat, Jochen Vogl, Tamara Gusarova, Michael Czerwensky, Hans-Joachim Heinrich, Akiharu Hioki, Leonid A. Konopelko, Brad Methven, Tsutomu Miura, Ole Petersen, Gundel Riebe, Ralph Sturgeon, Lee L. Yu
Within the National Metrology Institutes (NMIs) and designated laboratories, an interlaboratory comparison, CCQM-P107, was conducted to verify the degree of international comparability concerning the results of purity analysis. The mass fractions of Ag, Bi

A Volcano Curve: Optimizing Methanol Electro-oxidation on Pt decorated Ru Nanoparticles

June 26, 2009
Author(s)
Christopher D. Zangmeister, Savelas A. Rabb, Du Bingchen, YuYe Tong
Controlled Pt adlayers were deposited on commercial Ru nanoparticles (NPs) using an industrially scalable one-pot ethylene glycol (EG) reduction based method and were characterized by X-ray diffraction (XRD), electrochemical (EC) CO stripping voltammetry

Combinatorial Study of Thin Film Metal Hydride by Prompt Gamma Activation Analysis

June 19, 2009
Author(s)
Raymond Cao, Jason Hattrick-Simpers, Richard Bindel, Bryan E. Tomlin, Rolf L. Zeisler, Rick L. Paul, Leonid A. Bendersky, Robert G. Downing
Cold neutron prompt gamma activation analysis (PGAA) was used to determine the amount of hydrogen in thin film Mg hydrides with varying hydrogenation times. The results suggest that the hydrogenation in the Mg thin films remains unsaturated even after 48

Selective Binding of RNAse B Glycoforms by Polydopamine-immobilized Concanavalin A

June 10, 2009
Author(s)
Todd A. Morris, Alexander W. Peterson, Michael J. Tarlov
Glycoanalysis is important in the manufacture and quality control of protein therapeutics. An emerging method for glycoanalysis is the use of lectin arrays. Critical to the performance of these arrays is the immobilization of the lectin molecules

Generating and Using Data of Higher Dimension for Gas-Phase Chemical Sensing

May 29, 2009
Author(s)
Baranidharan Raman, Joshua L. Hertz, Kurt D. Benkstein, Douglas C. Meier, Casey Mungle, Stephen Semancik
Methods to acquire and analyze rich data streams from sensors are helpful, if not required, to track chemical components within complex gas-phase environments. We describe a MEMS-based microsensor technology that populates multi-element arrays with

SERS not to be taken for granted in the presence of oxygen

May 15, 2009
Author(s)
Melek Erol, Yun Han, Scott K. Stanley, Christopher Stafford, Henry Du, Svetlana Sukhishvili
In this communication, we report that oxidation of the Ag nanoparticle (Ag NP) surface under ambient conditions has a dramatic effect on the adsorption and SERS detection limit of nitroaromatic molecules in aqueous solutions. We show for the first time

A New Evaluation of the Half-life of 241Pu

April 14, 2009
Author(s)
Roger Wellum, Andre Verbruggen, Ruediger Kessel
A new evaluation of the half-life of 241Pu has been made by developing earlier methods and techniques and employing further measurements of the isotopic ratio of an initially enriched 241Pu material. A correction to the previous value has had to be made

Comparison of five extraction methods for measuring PCBs, PBDEs, organochlorine pesticides, and lipid content in serum

April 7, 2009
Author(s)
Jennifer M. Lynch, Aurore Guichard, Jennifer Yordy, Michele M. Schantz, John R. Kucklick, Robert R. Swarthout, Brianna K. Carlson
An increasing number of studies use blood obtained non-invasively to monitor organohalogen contaminants. However, blood can be a difficult tissue to analyze for organohalogen pollutants due to interferences from co-extracted proteins. We compared five

International NMR-based Environmental Metabolomics Intercomparison Exercise

April 7, 2009
Author(s)
Daniel W. Bearden, Mark Viant, Jacob Bundy, Ian Burton, Tim Collette, Drew Ekman, Tobias Karakach, Ching Y. Lin, Simone Rochfort, Jeff de Ropp, Quincy Teng, Ron Tjeerdema, John Walter, Huifeng Wu
Several fundamental requirements must be met so that NMR-based metabolomics can be formally adopted into environmental monitoring and chemical risk assessment. Here we report an intercomparison exercise which has evaluated the accuracy, precision and
Was this page helpful?