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.

Journals

Separation of Different Physical Forms of Plasmid DNA Using a Combination of Low Electric Field Strength and Flow in Porous Media: Effect of Different Field Gradients and Porosity of the Media

March 1, 2000

Author(s)

Kenneth D. Cole, C M. Tellez-Rodriguez, R W. Blakesley

The retention of different physical forms of DNA by an electric field in a chromatography system was studied. We were able to effectively separate the...

Comparison of generalized born and Poisson models: Energetics and dynamics of HIV protease

March 1, 2000

Author(s)

Lindra David, R Luo, M K. Gilson

Micromachined 28 GHz Power Divider in CMOS Technology

March 1, 2000

Author(s)

Mehmet Ozgur, Michael Gaitan, Mona E. Zaghloul

Excited States at Surfaces: Fano Profiles in STM Spectroscopy of Adsorbates

March 1, 2000

Author(s)

John William Gadzuk, M Plihal

The Fano-Anderson model for a discrete state embedded within a continuum is revisited within the context of excitation and decay processes which lead to some...

Monolithic Folded Resonator for Evanescent Wave Cavity Ringdown Spectroscopy

March 1, 2000

Author(s)

A C. Pipino

An optical resonator is characterized that employs both ultra-high-reflective coated surfaces and total-internal reflection to enable cavity ring-down...

Software Standards Development - Wherever - However - The Bugs are Free

March 1, 2000

Author(s)

Michael D. Hogan

The perceived tradeoff between the speed of development and the technical soundness of the resulting standards may not be relevant to the development of complex...

Variable Waveform Excitation of Ceramic-Element Transducers for ASTM E127-Type Reference Block Calibration

March 1, 2000

Author(s)

John A. Slotwinski, C R. Snydor, Ana Lopez-Sanchez

Nominally identical ceramic-element ultrasonic transducers have been used successfully to calibrate ASTM E127-type flat-bottom-hole (FBH) aluminum reference...

Fluorescence Anisotropy Sensor and Its Application to Polymer Processing and Characterization

March 1, 2000

Author(s)

Anthony J. Bur, S C. Roth, C L. Thomas

An optical sensor containing polarizing optical components has been constructed for the purpose of monitoring fluorescence anisotropy during polymer processing...

Adaptive Use of Prior Information in Inverse Problems: An Application to Neutron Depth Profiling

March 1, 2000

Author(s)

M Levenson, Kevin J. Coakley

A flexible class of Bayesian models is proposed to solve linear inverse problems. The models generalize linear regularization methods such as Tikhonov...

Effects of Domain Interfaces on the Rheological Properties of Polybutadiene / Polyisoprene Blends

March 1, 2000

Author(s)

H Jeon, A Nakatani, Charles C. Han, R H. Colby

The viscoelastic properties of a near critical polybutadiene(PB)/polyisoprene(PI) blends were investigated in oscillatory shear above and below the lower...

Interfacial Roughness Effects on Interlayer Coupling in Spin Values Grown on Different Seed Layers

March 1, 2000

Author(s)

D Parks, P J. Chen, William F. Egelhoff Jr., Romel Gomez

We have studied the behavior of interlayer coupling in giant magnetoresistance (GMR) spin valves as a function of seed valves as a function of seed layer...

Cancellation of Laser Dither Modulation From Optical Frequency Standards

March 1, 2000

Author(s)

M S. Taubman, J L. Hall

We demonstrate the removal of the dither modulation from an iodine-stabilized He-Ne laser by using a frequency-modulated acousto-optic modulator and feed...

Accurate f-Values for Ultraviolet Transitions From the 3d⁵ (⁶S) 4p Levels in Mn II

March 1, 2000

Author(s)

R Kling, Ulf Griesmann

We have measured branching fractions for ultraviolet electric dipole transitions from upper levels belonging to the 3d 5( 6S)4p 5P and 3d 5 ( 6S)4p 7P terms of...

Pulsed Terahertz Spectroscopy of DNA, Bovine Serum Albumin and Collagen Between 0.1 and 2.0 THz

March 1, 2000

Author(s)

A G. Markelz, A. E. Roitberg, Edwin J. Heilweil

We report the first use of pulsed terahertz spectroscopy to examine low frequency collective vibrational modes of biomolecules. Several absorption features were...

Core and Final-State Excitonic Effects and Resonant Inelastic X-Ray Scattering in s-p Bonded Solids

March 1, 2000

Author(s)

Eric L. Shirley

The much-discussed electron-hole attraction in resonant inelastic x-ray scattering is analyzed. Its effects on fluorescence yields and emission features are...

Cross Sections for Singly Differential and Total Ionization of Helium by Electron Impact

March 1, 2000

Author(s)

Yong Sik Kim, W R. Johnson, M E. Rudd

The Binary-Encounter Dipole (BED) model for electron-impact ionization is applied to helium using the continuum dipole oscillator strength calculated from the...

Vapor Pressure of Heptane from the Triple Point to the Critical Point

March 1, 2000

Author(s)

L A. Weber

We have used a metal ebulliometer to make measurements of the vapor pressure of heptane. Measurements spanned the temperature range from 335 K to 503 K, and...

Folding and Assembly of Rhodopsin from Expressed Fragments

March 1, 2000

Author(s)

K D. Ridge, N G. Abdulaev

The dim-light photoreceptor rhodopsin is a prototypical member of the family of seven-transmembrane helix receptors that are coupled to guanine nucletide...

Polymeric Silsesquioxanes: Degree-of-Intramolecular-Condensation Measured by Mass Spectrometry

March 1, 2000

Author(s)

William E. Wallace, Charles M. Guttman, Joseph M. Antonucci

The degree-of-condensation, defined as the number of residual silanol (SiOH) groups per oligomer, for a variety of silsesquioxane polymers was measured by...

Switched-Coupler Measurements for High Power FR Calibrations

March 1, 2000

Author(s)

J. W. Allen

Calibration of RF power sensors at levels greater than 10 mW and uncertainties on the order of 2 % need not require complex calorimetric methods. Using a series...

The Orientation of Semifluorinated Alkanes Attached to Polymers at the Surface of Polymer Films

March 1, 2000

Author(s)

Jan Genzer, E Sivaniah, E K. Kramer, J G. Wang, H Kerner, M Xiang, K Char, Christopher K. Ober, B M. DeKoven, Robert A. Bubeck, M K. Chaudhury, S Sambasivan, Daniel A. Fischer

The surface molecular orientation of a liquid crystalline (LC) layer made up a semi-fluorinated (SF) single side-groups [-CO-(CH 2) x-1-(CF 2) yF] (single SF...

Effects of Microstructural Evolution on the Thermal Diffusivity of α-Al₂O₃ Prepare from Nanosize γ-Al₂O₃ Powder

March 1, 2000

Author(s)

E J. Gonzalez, Grady S. White, L Wei

The thermal conductivity of porous α-Al 2O 3 specimens prepared using nanosize γ-Al 2O 3 powder or conventional sub-micro a}-alumina powders was studied. Plots...

Contact Damage in Porcelain/Pd-Alloy Bilayers

March 1, 2000

Author(s)

H Zhao, X Z. Hu, M T. Bush, Brian R. Lawn

An analysis is made of contact damage in brittle coatings on metal substrates, using as a case study a dental porcelain coating of thickness between 0.1 and 1...

Single-Crystalline Ceramic Whisker-Reinforced Carboxylic Acid-Resin Composites With Fluoride Release

March 1, 2000

Author(s)

H H. Xu, F Eichmiller, Joseph M. Antonucci, Glenn M. Flaim

Currently available glass ionomer, resin-modified glass ionomer and compomer materials are susceptible to brittle fracture and, therefore, are inadequate for...

Size and Confinement Effects on the Glass Transition Behavior of Polystyrene/O-Terphenyl Polymer Solutions

March 1, 2000

Author(s)

J K. Park, G B. McKenna

Polystyrene(PS)/o-terphenyl (oTP) solutions confined to nano-meter scale pores were studied by differential scanning calorimetry (DSC) to investigate size and...

Excitation of a Dipole Topological State in a Strongly Coupled Two-Component Bose-Einstein Condensate

March 1, 2000

Author(s)

Juana S. Williams, R Walser, J W. Cooper, Eric A. Cornell, M J. Holland

Two internal hyperfine states of a Bose-Einstein condensate in a dilute magnetically trapped gas of 87Rb atoms are strongly coupled by an external field that...

Guiding Laser-Cooled Atoms in Hollow-Core Fibers

March 1, 2000

Author(s)

D Mueller, Eric A. Cornell, D Z. Anderson, E. Abraham

Laser-cooled atoms from a low-velocity atomic source are guided in a hollow-core optical fiber using the evanescent-wave dipole force from blue-detuned laser...

Development of Oxygen Scavenger Additives for Future Jet Fuels. A Role for Electron-Transfer-Initiated Oxygenation (ETIO) of 1,2,5-Trimethylpyrrole?

March 1, 2000

Author(s)

B Beaver, V Sharief, Y Teng, R DeMunshi, J P. Guo, E Katondo, D Gallagher, David M. Bunk, J Grodkowski, Pedatsur Neta

Model autoxidative, radiolytic and product studies are presented which explore the potential of 1,2,5-trimethylpyrrole (TMP) as an oxygen scavenger additive for...

Cobalt-Corrin Catalyzed Photoreduction of CO₂

March 1, 2000

Author(s)

J Grodkowski, Pedatsur Neta

A first attempt to use cobalt corrins (B 12) as homogeneous catalysts for photoreduction of CO 2 to CO and formic acid demonstrates that the corrins act as...

NMR Evidence for an Unusually Low N1 pK_a for Uracil Bound to Uracil DNA Glycosylase: Implications for Catalysis

March 1, 2000

Author(s)

A C. Drohat, J T. Stivers

The first step of the DNA base-excision repair pathway is the removal of the damaged base by cleavage of the N-glycosidic bond through the action of a DNA...

Was this page helpful?