Accurate centre-of-mass corrections for geodetic spherical satellites are expected to contribute to accurate determination of the scale of the earth, i.e. , ...
NASA Website
Jul 10, 2011 ... The secondary purpose was to provide a means of accurately determining the mass of feces, vomitus and food residue generated in flight. ...
Diesel, gas turbine and liquid rocket engines requires the accurate knowledge of mass diffusion, Dij, and thermal diffusion, a~ij, coefficients. ...
Ion Composition Elucidation (ICE) utilizes selected ion recording with a double focusing mass spectrometer to simultaneously determine exact masses and relative isotopic abundances from mass peak profiles. These can be determined more accurately and at higher sensitivity ...
EPA Science Inventory
Exact mass measurements were obtained for a variety of potassium- and tetra-n-butylammonium organotrifluoroborates using commercially available organic sulfate salts as internal reference standards. Accuracies were determined within 5 ppm using a sector ESI mass spectrometer operating in the negative ionization mode.
PubMed Central
A method for obtaining protein molecular masses with an accuracy of approximately {plus minus}0.01% by matrix-assisted laser desorption using an internal calibrant is described. The technique allows accurate mass determinations of protein sample sizes as small as 1 pmol. High concentrations of organic and inorganic ...
Energy Citations Database
A knowledge of permeability is required to accurately assess and/or predict seepage conditions within a rock mass. This report reviews techniques available for measuring rock mass permeability and provides guidance concerning their application and interpr...
National Technical Information Service (NTIS)
Analytical research in the application of mass spectrometric techniques to the accurate determination of the molecular formula and hence the elemental composition of unknown samples is described. Specifically, it has been shown that these techniques can b...
Application of the spectrometric isotope dilution technique for the accurate determination of parts per million range of uranium in rock samples is described. The various aspects of the method like sample dissolution, ion exchange separation, mass spectro...
Sep 3, 2010 ... The analysis will be completely specific and exhibit no ... Current technologies , including gas chromatography, mass spectrometry, ...
determine whether, and on what time scale, global warming might lead to ... of the discretisation grids for numerical solutions to be based on accurate ...
Accurate, confirmed mass excess values have been determined for the nuclei60, 62Fe,68Ni,69Cu, and73, 75Ga by the Q-value method. The mass of74Zn requires further study. Good agreement was found between experimentally determined mass values and those from ...
NASA Astrophysics Data System (ADS)
For the past decade, we have used double focusing mass spectrometers to determine compositions of ions observed in mass spectra produced from compounds introduced by GC based on measured exact masses of the ions and their +1 and +2 isotopic profiles arising from atoms of ...
After a dispersive event, rapid determination of elemental compositions of ions in mass spectra is essential for tentatively identifying compounds. A Direct Analysis in Real Time (DART)� ion source interfaced to a JEOL AccuTOF� mass spectrometer provided exact masses accurate to ...
Saturated groundwater flow can often be described by the law of mass conservation and Darcy's law, i.e. by a potential flow problem. An accurate approximation of the specific discharge can be determined by the mixed finite element method. In this article ...
High-precision pulsar timing relies on a solar system ephemeris in order to convert times of arrival (TOAs) of pulses measured at an observatory to the solar system barycenter. Any error in the conversion to the barycentric TOAs leads to a systematic variation in the observed timing residuals; specifically, an incorrect planetary mass leads to a predominantly sinusoidal ...
placed at the center. For these measurements, myoglobin was used as the calibrant. The samples were also mixed with myoglobin and run again for more accurate mass determination with an internal calibration experiments in the following way. The mass spectra of the mixture of the gliadin sample with the myoglobin
E-print Network
For the calculation of wet cooling towers by the Merkel main equations of by the more accurate Poppe method numerical values are needed for the thermal and mass transfer coefficients. So far these coefficients were determined experimentally and it was tri...
Mass determination of cometary nuclei using nongravitational forces is reviewed and it is shown that accurate results can be reached if proper account can be taken of the influence of gas production perihelion asymmetry on the nongravitational effect. Thi...
The mathematical modeling and comparison of manikin headforms and helmet systems requires that the mass properties be accurately determined. The specific properties that must be known are the weight, center of gravity location, magnitudes of the principal...
There is increased interest in accurately assessing the total dietary intake of vitamins from all sources, including foods and dietary supplements. Isotope dilution mass spectrometry (IDMS) can be a definitive analytical method for very accurate concentration determinations. A liquid chromatographic...
Technology Transfer Automated Retrieval System (TEKTRAN)
Many beyond the standard model theories include a stable dark matter candidate that yields missing or invisible energy in collider detectors. If observed at the CERN Large Hadron Collider, we must determine if its mass and other properties (and those of its partners) predict the correct dark matter relic density. We give a new procedure for ...
PubMed
A novel diagnostic method is described that utilizes a thrust stand mass balance (TSMB) to directly measure time-accurate mass flow from a solid-fuel thruster. The accuracy of the TSMB mass flow measurement technique was demonstrated in three ways including the use of an idealized numerical simulation, verifying a ...
The masses of six neutron-deficient rare holmium and thulium isotopes close to the proton drip line were determined with the SHIPTRAP Penning trap mass spectrometer. For the first time the masses of the proton-unbound isotopes {sup 144,145}Ho and {sup 147,148}Tm were directly measured. The proton separation ...
The density determination of a small solid object with a mass of only a few hundred milligrams is always a difficult and often an ellusive measurement. The advent of highly accurate hydrostatic weighing techniques and the density scale based on solid obje...
The atomic weight of a reference sample of silver has been determined by mass spectrometry with an uncertainty of one part in 10 to the 6th power. Accurately known quantities of chemically pure (107)Ag and (109)Ag were mixed to produce standards of known ...
This patent describes a method of controlling heat input into a coke oven to obtain a desired temperature of the coke mass of the oven at the time of pushing. The steps are: (1) determine the moisture content and heat of carbonization of a sample of coal scheduled for transfer into the oven; (2) determine a coal ...
Object is measured for mass and center of mass with accuracies of 0.01% and 0.14 respectively, using
NASA Technical Reports Server (NTRS)
The object of the paper is to show how to make highly accurate mass measurements using an appropriate electronic balance without the use of external mass standards. The method eliminates the need for a set of external mass standards and, therefore the need to have these mass standards ...
The Penning trap mass spectrometer SMILETRAP is designed for precision mass measurements using the merits of highly charged ions. In this paper we describe the feature of SMILETRAP and give examples of mass measurements involving , , and ions. These emphasize the importance of accurate masses ...
The combination of high-precision gamma-ray measurements with precision mass determinations allows determination of fundamental constants, such as the neutron mass and the molar Planck constant. The basic principle of these measurements will be discussed. Experimental results from measurements with 29Si, 36Cl, and ...
There is increased interest in accurately assessing the total dietary intake of vitamins from all sources, including foods and dietary supplements. Isotope dilution can be a definitive analytical method for very accurate concentration determinations. Thus, a liquid chromatographic (LC) isotope dilut...
Stellar pulsation theory provides a means of determining the masses of pulsating classical Cepheid supergiants-it is the pulsation that causes their luminosity to vary. Such pulsational masses are found to be smaller than the masses derived from stellar evolution theory: this is the Cepheid ...
Although it has been over 50 years since the neutrino was postulated by Pauli and nearly 35 years since the first experimental evidence of neutrinos was observed by Reines and Cowan, the question of whether the neutrino has a non-zero mass still remains unanswered. Today, more than a dozen experiments observing the beta-decay of tritium are underway in the quest for an answer ...
... Accession Number : ADP000252. Title : An Accurate Determination of the Thermal Conductivity of Argon at High Temperatures,. ...
DTIC Science & Technology
... Title : ACCURATE DETERMINATION OF THE MOMENT OF INERTIA AND CENTER OF GRAVITY POSITION OF WIND TUNNEL MODELS. ...
Observations of H2O masers from circumnuclear disks in active galaxies for the Megamaser Cosmology Project (MCP) allow accurate measurement of the mass of supermassive black holes (BH) in these galaxies. We present the Very Long Baseline Interferometry images and kinematics of water maser emission in six active galaxies: NGC 1194, NGC 2273, NGC 2960 (Mrk ...
Today, it is necessary to identify relevant compounds appearing in discovery and development of new drug substances in the pharmaceutical industry. For that purpose, the measurement of accurate molecular mass and empirical formula calculation is very important for structure elucidation in addition to other available analytical methods. In this work, the ...
A major activity in the 20 year collaboration between the Analytical Chemistry Division at NIST and the College of American Pathologists (CAP) has been the development of highly accurate and precise 'definitive' methods for important clinical analytes in ...
The atomic weight of a reference sample of silver has been determined by mass spectrometry, with an uncertainty of one part in 10 to the 6th power, using a single filament silica gel procedure. Accurately known quantities of chemically pure 107 Ag and 109...
Stellar multiplicity is a fundamental astrophysical property. In addition to being the only physical basis for accurate mass determination, this parameter is believed to influence important aspects such as planet formation and stability. Contrary to earli...
Hazard assessment following challenge by ambient aerosols requires accurate estimation of exposure, that is, determination of the total mass of particulate matter deposited within the respiratory tract, and its intercompartmental distribution. Aerosol dep...
Hazard assessment following challenge by ambient aerosols requires accurate estimation of exposure, that is, determination of the total mass of particulate matter deposited within the respiratory tract, and its intercompartmental distribution. Aerosol deposition studies utilizing...
An accurate determination of the bone mineral mass of lumbar vertebrae is needed as a measurement of bone demineralization in weight-bearing bones in addition to the more routinely performed measurements of the extremities. A system was developed utilizin...
A review is given of nonleptonic decays of D mesons. Measurements of the psi (3772), the accurate determination of D masses and their consequences, inclusive measurements and tagged events are given. 36 references. (ERA citation 03:034070)
Work on the determination of the polymeric composition of LiF vapor in equilibrium with the condensed phase was continued using beam modulation mass spectrometry. It was found that accurate experimental measurements could not be made for LiF and Li3F2 bec...
The determination and rational assessment of groundwater flow around a repository depends upon the accurate analysis of several interdependent and coupled phenomenological events occuring within the rock mass. In particular, the groundwater flow pathways ...
The Naval Research Laboratory has pioneered a fast and accurate method of processing standard data on spacecraft orbits ('two-line element sets' or TLEs) to determine the total mass density of the highest layer of the Earth's atmosphere, known as the ther...
A summary is given of the results presented at the 2nd Workshop on (tau) lepton physics (Ohio State University, September 1992). They highlight a precise determination of the (tau) mass, new accurate results of the (tau) lifetime, much improved measuremen...
The M dwarf stars impact a significant range of topics in contemporary astrophysics. Their sheer numbers inevitably influence galactic dynamics and structure. The eventual accurate determination of their mass function at faint magnitudes will provide a cr...
The new mass spectrometric determination of the atomic weight of thallium has been completed. A high precision assay technique was developed so that accurately known quantities of the 203Tl and 205Tl separated isotopes could be mixed to produce standards ...
Penning trap mass measurements of neutron-deficient Cd isotopes Cd99-109 have been performed with the ISOLTRAP mass spectrometer at ISOLDE/CERN, all with relative mass uncertainties below 3�10-8. A new mass evaluation has been performed. The mass of Cd99 has been ...
Total mercury mass in oil shale retort offgas was quantified in a series of laboratory retorting experiments and in a simulated modified in-situ (MIS) retorting experiment. Accurate quantitative determinations of offgas Hg mass were made possible by the use of a continuous on-lin...
The Volterra method of the multiplicative integral is used to determine the isotopic density, mass, and energy production in linear systems. The solution method, assumptions, and limitations are discussed. The method allows a rapid accurate calculation of the change in isotopic density, mass, and energy production ...
We combine results from interferometry, asteroseismology and spectroscopic analyses to determine accurate fundamental parameters (mass, radius and effective temperature) of 10 bright solar-type stars covering the H-R diagram from spectral type F5 to K1. Using �direct� techniques that are only weakly model-dependent we ...
MALDI tissue imaging of tissues has become a promising technique for tracking biomarkers while determining their location and structural characterization. We have now developed specific targeting probes (oligonucleotides, antibodies), named Tag-Mass. This approach is based on probes modified with a photocleavable linker coupled with a tag cleaved and ...
The structural elucidation of small molecules using mass spectrometry plays an important role in modern life sciences and bioanalytical approaches. This review covers different soft and hard ionization techniques and figures of merit for modern mass spectrometers, such as mass resolving power, mass accuracy, ...
Placement of sensors is one of the most important tasks performed during pretest planning. The purpose of this work was to develop and investigate the use of an iterative Guyan expansion for mass weighting of target modes for sensor placement analogous to the common iterative Guyan reduction technique. The goal was to determine the appropriate ...
Using a novel orbitrap mass spectrometer, the authors investigate the dynamic range over which accurate masses can be determined (extent of mass accuracy) for short duration experiments typical for LC/MS. A linear ion trap is used to selectively fill an intermediate ion storage device (C-trap) ...
Simulation of Electron and Ion Lenses for Mass Spectrometry ... accurate performance simulations of mass spectrometers used for detection and measurement of ...
For many decades the accurate and precise determination of isotope ratios has remained a very strong interest to many researchers due to its important applications in earth, environmental, biological, archeological, and medical sciences. Traditionally, thermal ionization mass spectrometry (TIMS) has been the technique of choice for ...
Calorimetry is a primary measurement technique for assay of quantities of plutonium in the United States. It is the most accurate NDA technique for many forms of plutonium-bearing materials. This paper provides an overview of the use of calorimetry in combination with high-resolution gamma-ray spectroscopy for accurate plutonium mass ...
Stable incorporation of labeled amino acids in cell culture is a simple approach to label proteins in vivo for mass spectrometric quantification. Full incorporation of isotopically heavy amino acids facilitates accurate quantification of proteins from different cultures, yet analysis methods for determination of incorporation are ...
Closed-cycle and energy-balance calculations are useful in predicting properties of nuclides. With these calculations it is possible to determine accurately the atomic masses of unstable nuclides that, because of their short half-lives, make direct spectrographic determinations quite difficult. The ...
A program of precise eclipsing binary photometry with the NASA Kepler Observatory is now in progress. Our goal is to search for variations in minimum light timing for intermediate mass eclipsing binaries. Such periodic variations will reveal the reflex motion caused by any distant, low mass object that orbits the close binary. Kepler's unprecedented ...
We are working on a program of precise photometry with the NASA Kepler Observatory to search for variations in minimum light timing for intermediate mass eclipsing binaries. Such periodic variations will reveal the reflex motion caused by any distant, low mass object that orbits the close binary. Kepler's unprecedented accuracy and continuous observations ...
The accurate determination of atomic masses and the high-precision measurement of the bound-electron g factor are prerequisites for the determination of the electron mass, which is one of the fundamental constants of nature. In the 2002 CODATA adjustment [P.J. Mohr, B.N. Taylor, Rev. Mod. Phys. ...
It is possible to determine the mean molecular mass of a planetary atmosphere using pressure and temperature measurements made by an entry probe descending at terminal velocity. The descent trajectory of an entry probe can be determined from pressure, temperature, and mean molecular mass data. This technique offers ...
We studied the electrophoretic behavior of basic proteins (cytochrome c and histone III) and developed a carbamylation method that normalizes their electrophoretic size separation and improves the accuracy of their relative molecular mass determined electrophoretically. In capillary zone electrophoresis with cationic hitchhiking, native cytochrome c does ...
Gravimetric measurement of gases is one of the methods available for calibrating gas volumes. By inputting a known quantity of gas and measuring the resulting pressure and temperature, the system volume can be calculated using gas law principles. Historically, this method has been less accurate due to the difficulty in the mass ...
DOE Information Bridge
A magnetic flux measuring system was converted for the identification of M/e positions in a 6-inch radius, directional focusing, mass spectrometer. The voltage generated by a synchronous motor-driven rotating coil'' placed in the magnetic field of the analyzer section of the mass spectrometer is measured by a potentiometer. ...
A classic problem in analytical chemistry has been determination of individual components in a mixture without availability of the pure individual components. Measurement of the distribution of isotopomers in a labeled compound or mixture of labeled compounds is an example of this problem that is commonly encountered when stable isotopically labeled metabolites are used to ...
The Avogadro constant links the atomic and the macroscopic properties of matter. Since the molar Planck constant is well known via the measurement of the Rydberg constant, it is also closely related to the Planck constant. In addition, its accurate determination is of paramount importance for a definition of the kilogram in terms of a fundamental constant. ...
...denaturants may be made by volume, weight, accurate mass flow meter, or by any...spirits to be denatured by volume, weight, accurate mass flow meter, or other...denaturants to be used by volume, weight, accurate mass flow meter, or...
Code of Federal Regulations, 2011
By using the highly improved staggered quark formalism to handle charm, strange, and light valence quarks in full lattice QCD, and NRQCD to handle bottom valence quarks, we are able to determine accurately ratios of the B meson vector-pseudoscalar mass splittings, in particular, [m(B{c}{*})-m(B{c})]/[m(B{s}{*})-m(B{s})]. We find this ...
Mass profile determinations for dispersion supported galaxies from line-of-sight velocities are subject to large uncertainties associated with the unknown stellar velocity anisotropy. We demonstrate both analytically and with available kinematic data that the mass-anisotropy degeneracy is effectively eliminated at a characteristic ...
The intravenous anesthetic etomidate was measured in human plasma by mass fragmentography. The method is accurate, sensitive, and specific. Results of the analyses indicate that after a single 0.3-mg/kg iv dose of etomidate, there are at least three phases in its disappearance from human plasma. Detectable plasma concentrations exist for more than 6 hr ...
This is a continuation of a project begun in Cycle 7 and continued up through Cycle 11. The program consists of annual or biannual WFPC2 or FGS observations of three visual binary stars that will ultimately yield fundamental astrophysical results, once their orbits and masses are determined. Our targets are the following: {1} Procyon {P = 41 yr}, for which ...
Peptide sequence identification using tandem mass spectroscopy remains a major challenge for complex proteomic studies. Peptide matching algorithms require the accurate determination of both the mass and charge of the precursor ion and accommodate uncertainties in these properties by using a wide precursor ...
By directly introducing one microlitre of distillate of urine, blood serum, etc., into the sample reservoir of a mass spectrometer, it is pcssible to determine the ratio of HDO to H/sub 2/O molecules in the vapor to within a standard deviation corresponding to 2%. Duplicate determinations can be performed in 5 minutes, not ...
Age is a key parameter when deducing the history of plutonium material, i.e. the plutonium produced in the nuclear reactors. This is of vital importance, when a smuggled plutonium sample has been seized and the origin has to be determined. A methodology is described which allows accurately to determine the age of plutonium material by ...
The study of nuclear electron capture (EC) offers an exciting alternative for the determination of the neutrino mass. Whereas only tritium and 187Re can be used in the case of ?-decay experiments involving the anti-neutrino, a potentially large number of EC-nuclides can be used in experiments involving the monochromatic neutrino. This alternative to ...
After the accident at Three Mile Island, Unit 2 (TMI-2), on March 28, 1979, GEND stated its intention to support an effort to determine, as accurately as possible, the current mass balances of significant radiological toxic species. GEND gave two primary reasons for support this effort: (1) such exercises guarantee completeness of the ...
An improvement within an oxygen-iodine chemical laser in the form of a mass flow rate detector for rapidly, accurately, and reliably detecting the mass flow rate of iodine into the resonant cavity of the laser. A mass flow rate detector has an adsorption cell to which either an inert gas or an iodine-inert gas ...
We propose to obtain high precision, high time resolution X-ray observations of the high mass X-ray binary 4U0900-40, as part of a multi-wavelength campaign to unambiguously measure the mass of the compact companion. UV time series obtained with HST reveal the presence of reprocessed X-ray pulses emanating from the atmosphere of the primary. Thus, ...
Bifilar pendulum, if great care is taken to provide accurate measurements, is very accurate (in .... Seismic accelerometers were able to measure mass line ...
The U.S. Naval Observatory Flagstaff Station (NOFS) has been providing highly accurate astrometry to the Solar Systems Dynamics (SSD) group at JPL since 1991, in support of numerous planetary missions and observing efforts. In 2005, NOFS began a new phase of this work by expanding the range of possible targets, investigating the magnitude variability of asteroids observed at ...
Phosphodiesterase type 5 (PDE-5) inhibitors are a class of drugs used primarily in the treatment of erectile dysfunction. The Food and Drug Administration (FDA) approved PDE-5 inhibitors include sildenafil citrate, vardenafil hydrochloride and tadalafil. In this study, accurate mass measurements were made by electrospray ionization (ESI) using Fourier ...
The recent implementation of gas-filled radiofrequency traps for efficient ion beam bunching extended the applicability of the Penning trap mass spectrometer ISOLTRAP/CERN to non-surface ionizable species. In a first series of successful runs the masses of 182 197Hg, 196,198Pb, 197Bi, 198Po and 203At have been determined with an ...
The knowledge of accurate distances to Planetary Nebulae (PNe) is necesary in order to improve the determination of some physical quantities such as the nebular radius and mass. The nebular mass is a critical parameter to determine the amount of mass that is returned to the ...
SDS-PAGE is a simple, rapid technique that has many uses in biochemistry and is readily adaptable to the undergraduate laboratory. It is, however, a technique prone to several types of procedural pitfalls. This article describes the use of SDS-PAGE to determine the subunit molecular mass and composition of yeast alcohol dehydrogenase employing ...
ERIC Educational Resources Information Center
The feasibility of a method based on mass preservation [G. Schwarz, J. Zhang, Chem. Phys. Lipids, 110 (2001) 35�45] to determine the solubility of Cholesterol in water from monomolecular films on air/water interface was investigated. Using a mass balance equation, it was found that Cholesterol undergoes an exponential desorption at ...
Mass measurements on radionuclides along the potassium isotope chain have been performed with the ISOLTRAP Penning trap mass spectrometer. For {sup 35}K (T{sub 1/2}=178 ms) to {sup 46}K (T{sub 1/2}=105 s) relative mass uncertainties of 2x10{sup -8} and better have been achieved. The accurate ...
