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Michele M. Schantz, Rebecca S. Pugh, Stacy S. Schuur, Stephen A. Wise
The stability of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and chlorinated pesticides in frozen mussel tissue Standard Reference Materials (SRMs) stored at -80 °C was assessed by analyzing samples of SRM 1974, SRM 1974a
Miki Watanabe, Katherine Meyer, Tyler Jackson, Tracey Johnston, Ed Johnson, Dan Bearden
Zebra mussel, Dreissena polymorpha, in the Great Lakes is being monitored as a bio-indicator organism for environmental health effects by the National Oceanic and Atmospheric Administration's Mussel Watch program. In order to monitor the environmental
The National Institute of Standards and Technology (NIST) has established a Vitamin D Metabolites Quality Assurance Program (VitDQAP) in collaboration with the National Institutes of Health (NIH) Office of Dietary Supplements. Participants in the seventh
Vladimir Aksyuk, Basudev Lahiri, Glenn Holland, Andrea Centrone
Surface-enhanced infrared absorption (SEIRA) spectroscopy exploits the locally enhanced field surrounding plasmonic metamaterials to increase the sensitivity of infrared spectroscopy. Light polarization and incident angle are important factors for exciting
Bruce D. Ravel, Wantana Klysubun, Christoph Hauzenberger, Prapong Klysubun, Yuying Huang, Weeraya Wongtepa, Panidtha Sombunchoo
Two samples of the blue glass produced in the middle 19th century from the Temple of the Emerald Buddha in Bangkok, Thailand, were studied in order to understand the origin of its blue color. The oxide components and trace elements are quantitatively
Accurate characterization of the molar mass and size of polysaccharides is an ongoing challenge, oftentimes due to architectural diversity but also to the broad molar mass (M) range over which a single polysaccharide can exist and to the ultra-high M of
This paper presents superconformal feature filling during zinc electrodeposition in a sulfate electrolyte. Localized bottom-up filling of Through Silicon Vias (TSVs) with no deposition on the sidewalls or the field around them is presented in electrolytes
Siddharth Hazra, Jack L. Beuth, Grant A. Myers, Frank W. DelRio, Maarten de Boer
We present the design and extensive validation of a micromachined gripper array that enables reliable transmission of forces up to 10 milliNewtons. The gripper is constructed with polycrystalline silicon, a brittle material. Two ingressive snap-and-lock
A new microscale platform is reported which is based on microfabrication methods that integrate thermal control and multi-electrode components to enable rapid temperature-dependent electrochemical measurements on small volume fluid samples. We demonstrate
Dagistan Sahin, Vladimir Radulovic, Richard M. Lindstrom, Andrej Trkov
It has been difficult to characterize the thermal to epithermal neutron flux ratio (f) and the measure of the nonideal epithermal neutron flux distribution (α) for the RT-2 pneumatic rabbit facility at the NIST National Bureau of Standards Reactor (NBSR)
Lucy J. Carpenter, Stefan Reimann, Andreas Engel, Stephen Montzka, James B. Burkholder, Cathy Clerbaux, Bradley Hall, Shari A. Yvon-Lewis, Donald R. Blake, Marcel Dorf, Geoffre S. Dutton, Paul J. Fraser, Lucien Froidevaux, Fran?ois Hendrick, Jianxin Hu, Ashley Jones, Paul B. Krummel, Lambert J. Kuijpers, Michael J. Kurylo, Qing Liang, Emmanuel Mahieu, Jens M?hle, Simon O?Doherty, Keiichi Ohnishi, Vladimir L. Orkin, Klaus Pfeilsticker, Matt Rigby, Isobel J. Simpson, Yoko Yokouchi
Changes in the global atmospheric abundance of a substance are determined by the balance between its emissions and removal. Declines observed for ozone-depleting substances (ODSs) controlled under the Montreal Protocol are due to global emission reductions
Laura Espinal, Martin L. Green, Dean M. DeLongchamp, Watcharop Chaikittisilp, Jarod C. Horn, Miles Sakwa-Novak, Cherno Jaye, Daniel A. Fischer, Nicholas Brunelli, Christopher Jones
Near edge x-ray absorption fine structure (NEXAFS) spectroscopy was used to study the adsorption of CO2 in a hyperbranched aminosilica (HAS) compound, a porous solid state material with great potential for carbon capture applications. After dosing a
Walter R. Miller Jr., George C. Rhoderick, Franklin R. Guenther
Between June 2010 and June 2011, the National Institute of Standards and Technology gravimetrically prepared a suite of 20 carbon dioxide [CO2] in air primary standard mixtures [PSMs]. Ambient mole fraction levels were obtained through six levels of
The microwave spectrum of the molecular complex of acetonitrile (CH3CN) with water (H2O) has been studied with a pulsed-beam Fourier Transform Microwave Spectrometer (FTMW) from a gas sample of 1 % by volume of CH3CN in Ar flowed over a water sample. The
Walter J. Lafferty, Jean-Marie Flaud, Fridolin Kwabia
Absolute individual line intensities of numerous transitions of the fundamental ν15, ν12 and ν5 bands of oxirane (ethylene oxide, cyc-C2H4O) have been measured in the 790-940 cm-1 region using seven high-resolution Fourier transform spectra recorded at 0
Pedatsur Neta, Mahnaz Farahani, Yamil Simon, Yuxue Liang, Xiaoyu Yang, Stephen E. Stein
While determining the fragmentation pathways of positive ions of drugs, pesticides, metabolites, and other compounds, using electrospray ionization mass spectrometry, we noticed that certain product ions react with water in the collision cell. This
Michael R. Moldover, James W. Schmidt, Keith A. Gillis, James B. Mehl, John D. Wright
Using microwave techniques that are scalable to very large volumes, we measured the interior volume of a 0.3 m 3, commercially-manufactured, pressure vessel with an uncertainty of 0.05 %, as confirmed by independent, more-accurate, gas-expansion
Justin M. Shaw, Patrik Grychtol, Dmitriy Zusin, Ronny J. Knut, Tenio Popmintchev, Hans T. Nembach, Avner Fleischer, Henry Kapteyn, Margaret Murnane, Ofer Kfir, Oren Cohen
Circularly-polarized extreme UV and X-ray radiation provides valuable access to the structural, electronic and magnetic properties of materials. To date, this capability was available only at large-scale X-ray free-electron lasers or synchrotrons. Here we
The location, number, and migrating behavior of the sextets in the cata-condensed benzenoid polycyclic aromatic hydrocarbons with available bay regions have been determined by a new methodology called the extended Y-rule. The precursor of this rule is the
We demonstrate all-optical multilogic gate operations and transistor functionalities using a Kerr phase gate method in a room-temperature 85Rb vapor. Two symmetric Mach-Zehnder interferometers are constructed in the same vapor cell in which a Raman gain
The coupling of ultrasonic nebulization and extractive electrospray ionization (EESI) for the mass spectrometric (MS) detection and analysis of inorganic compounds from discrete liquid samples was demonstrated. The rapid detection, high throughput
Alexander Peterson, Michael Halter, Alessandro Tona, Anne Plant
Background Surface plasmon resonance imaging (SPRI) is a label-free technique that can image refractive index changes at an interface. We have previously shown that SPRI can be used to study the dynamics of cell-substratum interactions. However
Jeffrey W. Hudgens, Steven M. Swift, Ryan D. Heselpoth, Patrick M. Bales, Daniel C. Nelson
Alginate is a polysaccharide produced by certain seaweeds and bacteria that consists of mannuronic acid and guluronic acid residues. Seaweed alginate is used in food and industrial chemical processes, while the biosynthesis of bacterial alginate is
Julien C. Gigault, Thao M. Nguyen, John M. Pettibone, Vincent A. Hackley
In this work we have developed and validated a methodology for determining the size distribution in polydisperse cationic nanoparticle (NP) samples using asymmetric-flow field flow fractionation (A4F), where known compositional influence of previously used
We present measurements of approximately 70 isolated, self-broadened, water vapor lines which are assigned to the (1,0,1)(0,0,0), (0,0,2)(0,0,0), (1,2,0)(0,0,0), and (2,0,0)(0,0,0) vibrational bands and which occur in the transparency window region