oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 39 )

2018 ( 54 )

2017 ( 72 )

2016 ( 62 )

Custom range...

Search Results: 1 - 10 of 20212 matches for " Richard Newman "
All listed articles are free for downloading (OA Articles)
Page 1 /20212
Display every page Item
3D Fluorescence Characterization of Synthetic Organic Dyes—Effect of pH  [PDF]
Leonard J. Soltzberg, Sarah Flynn, Vera Kirch, Richard Newman
American Journal of Analytical Chemistry (AJAC) , 2013, DOI: 10.4236/ajac.2013.410067
Abstract:

The fingerprint character and high sensitivity of 3D UV-vis fluorescence spectra offer special advantages for identification of dyes in a museum or forensic setting. However, the extraction process is likely to affect the pH of the medium and, in some cases, may alter the dye itself. We report a study of 65 dyes extracted from wool fibers that are part of the Schweppe Collection of Important Synthetic Dyes. The 3D fluorescence spectra of the dye extracts at pH 1 and pH 14 are compared with the same dyes from the Schweppe solution library, run under the same conditions, as well as with the 3D fluorescence spectra of the dyes taken directly from the solution library without pH control. This analysis leads to guidelines for the use of such spectra in identifying unknown dye samples.

3D Fluorescence Characterization of Synthetic Organic Dyes  [PDF]
Leonard J. Soltzberg, Sandy Lor, Nnennaya Okey-Igwe, Richard Newman
American Journal of Analytical Chemistry (AJAC) , 2012, DOI: 10.4236/ajac.2012.39081
Abstract: The identification of dyes is important in research on museum artefacts as well as in forensic applications. UV-visible absorption spectroscopy cannot unambiguously distinguish dyes with similar hues, while mass spectrometry may fail to distinguish isobaric dyes. The detailed patterns produced by 3D fluorescence spectroscopy appear to be virtually unique, even among dyes that are closely related positional isomers. We report these patterns for 65 dyes from the Schweppe Library of Synthetic Organic Dyes as well as measurements suggesting both the capabilities and limitations of this method.
NP Stokes fields for radio astronomy
Ezra T. Newman,Richard H. Price
Physics , 2010, DOI: 10.1103/PhysRevD.82.083516
Abstract: The spin weighted spherical harmonic (SWSH) description of angular functions typically is associated with the Newman-Penrose (NP) null tetrad formalism. Recently the SWSH description, but not the NP formalism, has been used in the study of the polarization anisotropy of the cosmic microwave background. Here we relate this application of SWSHs to a description of electromagnetic radiation and polarization in the NP formalism. In particular we introduce NP Stokes fields that are the NP equivalent of the Stokes parameters. In addition to giving a more coherent foundation for the recent cosmological SWSH application, the NP formalism aids in the computation of the Lorentz transformation properties of polarization.
Non-Verbal Presence: How Changing Your Behaviour Can Increase Your Ratings for Persuasion, Leadership and Confidence  [PDF]
Richard Newman, Adrian Furnham, Laura Weis, Marcus Gee, Roxana Cardos, Alixe Lay, Alastair McClelland
Psychology (PSYCH) , 2016, DOI: 10.4236/psych.2016.74050
Abstract:

This study looks at how people rate specific non-verbal cues (NVC) with regard to the presence and persuasiveness of the speaker. The first study (N = 1500) was conducted to attempt to isolate specific non-verbal signals (hands and feet) that were related to ratings on influence and persuasiveness. In the second study, over 600 people rated a high quality video of an actor speaking. A sex by age by race by NVC ANOVA on six ratings, a total score and a question about voting showed a very consistent pattern with strong main effects for NVC, especially in ratings of confidence and persuasiveness. There were few significant interactions. Implications for training public speakers are considered. Limitations of the research are also noted.

Decoupling Economic Growth from Fossil Fuels  [PDF]
Peter Newman
Modern Economy (ME) , 2017, DOI: 10.4236/me.2017.86055
Abstract: The decoupling of fossil fuels from economic growth has not been imaginable for most of the industrial era but is now underway. The data for this are presented for the world and for typical nations. The mechanisms behind this are outlined and suggest that climate change goals to end poverty and to achieve the phasing out of fossil fuels are achievable if the trends are mainstreamed.
ELUCIDATION OF PROTEIN STRUCTURAL AND PHARMACOPHORE FEATURES BASED ON SEQUENCE CLUSTERING BY COMMON NEIGHBOR COMPARISONS
Richard Kho,Mark Hansen,Brian Baker,Joe Newman
The Scientific World Journal , 2002, DOI: 10.1100/tsw.2002.9
Abstract:
Keck Spectroscopy of z>1 Field Spheroidals: Dynamical Constraints on the Growth Rate of Red "Nuggets"
Andrew B. Newman,Richard S. Ellis,Tommaso Treu,Kevin Bundy
Physics , 2010, DOI: 10.1088/2041-8205/717/2/L103
Abstract: We present deep Keck spectroscopy for 17 morphologically-selected field spheroidals in the redshift range 1.05 10^11 Msol) grew in size over 0 Mdyn > 10^10 Msol) did not grow significantly. These trends are consistent with a picture in which more massive spheroidals formed at higher redshift via "wetter" mergers involving greater dissipation. To examine growth under the favored "dry" merger hypothesis, we also examine size growth at a fixed velocity dispersion. This test, uniquely possible with our dynamical data, allows us to consider the effects of "progenitor bias." Above our completeness limit (sigma > 200 km/s), we find size growth consistent with that inferred for the mass-selected sample, thus ruling out strong progenitor bias. To maintain continuity in the growth of massive galaxies over the past 10 Gyr, our new results imply that size evolution over 1.32 are truly massive and compact.
Luminous and Dark Matter Profiles from Galaxies to Clusters: Bridging the Gap with Group-scale Lenses
Andrew B. Newman,Richard S. Ellis,Tommaso Treu
Physics , 2015,
Abstract: Observations of strong gravitational lensing, stellar kinematics, and larger-scale tracers enable accurate measures of the distribution of dark matter (DM) and baryons in massive early-type galaxies (ETGs). While such techniques have been applied to galaxy-scale and cluster-scale lenses, the paucity of intermediate-mass systems with high-quality data has precluded a uniform analysis of mass-dependent trends. With the aim of bridging this gap, we present new observations and analyses of 10 group-scale lenses at =0.36 characterized by Einstein radii theta_Ein=2.5"-5.1" and a mean halo mass of M_200=10^14.0 Msol. We measure a mean concentration c_200=5.0+-0.8 consistent with unmodified cold dark matter halos. By combining our data with other lens samples, we analyze the mass structure of ETGs in 10^13 Msol-10^15 Msol halos using homogeneous techniques. We show that the slope of the total density profile gamma_tot within the effective radius depends on the stellar surface density, as demonstrated previously, but also on the halo mass. We analyze these trends using halo occupation models and resolved stellar kinematics with the goal of testing the universality of the DM profile. Whereas the central galaxies of clusters require a shallow inner DM density profile, group-scale lenses are consistent with a Navarro-Frenk-White profile or one that is slightly contracted. The largest uncertainties arise from the sample size and likely radial gradients in stellar populations. We conclude that the net effect of baryons on the DM distribution may not be universal, but more likely varies with halo mass due to underlying trends in star formation efficiency and assembly history.
Stellar populations from spectroscopy of a large sample of quiescent galaxies at z > 1: Measuring the contribution of progenitor bias to early size growth
Sirio Belli,Andrew B. Newman,Richard S. Ellis
Physics , 2014, DOI: 10.1088/0004-637X/799/2/206
Abstract: We analyze the stellar populations of a sample of 62 massive (log Mstar/Msun > 10.7) galaxies in the redshift range 1 < z < 1.6, with the main goal of investigating the role of recent quenching in the size growth of quiescent galaxies. We demonstrate that our sample is not biased toward bright, compact, or young galaxies, and thus is representative of the overall quiescent population. Our high signal-to-noise ratio Keck LRIS spectra probe the rest-frame Balmer break region which contains important absorption line diagnostics of recent star formation activity. We obtain improved measures of the various stellar population parameters, including the star-formation timescale tau, age and dust extinction, by fitting templates jointly to both our spectroscopic and broad-band photometric data. We identify which quiescent galaxies were recently quenched and backtrack their individual evolving trajectories on the UVJ color-color plane finding evidence for two distinct quenching routes. By using sizes measured in the previous paper of this series, we confirm that the largest galaxies are indeed among the youngest at a given redshift. This is consistent with some contribution to the apparent growth from recent arrivals, an effect often called progenitor bias. However, we calculate that recently-quenched objects can only be responsible for about half the increase in average size of quiescent galaxies over a 1.5 Gyr period, corresponding to the redshift interval 1.25 < z < 2. The remainder of the observed size evolution arises from a genuine growth of long-standing quiescent galaxies.
Can Minor Merging Account for the Size Growth of Quiescent Galaxies? New Results from the CANDELS Survey
Andrew B. Newman,Richard S. Ellis,Kevin Bundy,Tommaso Treu
Physics , 2011, DOI: 10.1088/0004-637X/746/2/162
Abstract: The presence of extremely compact galaxies at z~2 and their subsequent growth in physical size has been the cause of much puzzlement. We revisit the question using deep infrared Wide Field Camera 3 data to probe the rest-frame optical structure of 935 host galaxies selected with 0.4 10^10.7 Msol using optical and near-infrared photometry in the UKIRT Ultra Deep Survey and GOODS-South fields of the CANDELS survey. At each redshift, the most compact sources are those with little or no star formation, and we find that the mean size of these systems grows by a factor of 3.5 +- 0.3 over this redshift interval. The new data are sufficiently deep to enable us to identify companions to these hosts whose stellar masses are ten times smaller, while still yielding suitably accurate photometric redshifts to define a likely physical association. By searching for faint companions around 404 quiescent hosts within a projected physical annulus 10 < R < 30 kpc/h, we estimate the minor merger rate over the redshift range 0.4 < z < 2. After correcting for contamination from projected pairs, we find that 13-18% of quiescent hosts have likely physical companions with stellar mass ratios of 0.1 or greater. Mergers of these companions will typically increase the host mass by 6+-2% per merger timescale. We estimate the minimum growth rate necessary to explain the declining abundance of compact galaxies. Using a simple model of merging motivated by recent numerical simulations, we then assess whether mergers of the faint companions with their hosts are sufficient to explain this minimal rate. We find that mergers with mass ratios > 0.1 may explain most of the size evolution observed at z >~ 1 if a relatively short merger timescale is assumed, but the rapid growth seen at higher redshift likely requires additional physical processes.
Page 1 /20212
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.