Physical Sciences and Mathematics Commons^™

Retrieval Of Aerosol Microphysical Properties From Aeronet Photopolarimetric Measurements: 1. Information Content Analysis, Xiaoguang Xu, Jun Wang

Department of Earth and Atmospheric Sciences: Faculty Publications

This paper is the first part of a two-part study that aims to retrieve aerosol particle size distribution (PSD) and refractive index from the multispectral and multiangular polarimetric measurements taken by the new-generation Sun photometer as part of the Aerosol Robotic Network (AERONET). It provides theoretical analysis and guidance to the companion study in which we have developed an inversion algorithm for retrieving 22 aerosol microphysical parameters associated with a bimodal PSD function from real AERONET measurements. Our theoretical analysis starts with generating the synthetic measurements at four spectral bands (440, 675, 870, and 1020 nm) with a Unified Linearized …

Ua1c11/55 Gordon Wilson Photo Collection, Wku Archives

WKU Archives Collection Inventories

Photographs taken by and of Gordon Wilson.

Masthead

Journal of Digital Forensics, Security and Law

No abstract provided.

Front Matter

Journal of Digital Forensics, Security and Law

No abstract provided.

Impact Of The Municipal Solid Waste Incineration Plant In Warsaw On Air Quality, Robert Oleniacz

Robert Oleniacz

The only Polish municipal solid waste (MSW) incinerator has been operating within the Municipal Solid Waste Disposal Plant in Warsaw since 2000. In the paper selected results of the air quality impact assessment for this incinerator during an operating period of one year (2008) are presented. With respect to the incinerated waste amounts and emission levels, the analysed period can be considered typical for this facility. Assessment of the air quality impact was carried out by assessing air pollutant emissions in reference to the applicable emission limit values and by modeling atmospheric dispersion of these pollutants. It has been found …

Measurement Of Compton Scattering From The Deuteron And An Improved Extraction Of The Neutron Electromagnetic Polarizabilities, L. S. Myers, J. R. M. Annand, J. Brudvik, G. Feldman, H. W. Grießhammer, K. Hansen, S. S. Henshaw, L. Isaksson, R. Jebali, Michael A. Kovash, M. Lundin, J. A. Mcgovern, D. G. Middleton, A. M. Nathan, D. R. Phillips, B. Schröder, S. C. Stave

Physics and Astronomy Faculty Publications

The electromagnetic polarizabilities of the nucleon are fundamental properties that describe its response to external electric and magnetic fields. They can be extracted from Compton-scattering data—and have been, with good accuracy, in the case of the proton. In contradistinction, information for the neutron requires the use of Compton scattering from nuclear targets. Here, we report a new measurement of elastic photon scattering from deuterium using quasimonoenergetic tagged photons at the MAX IV Laboratory in Lund, Sweden. These first new data in more than a decade effectively double the world data set. Their energy range overlaps with previous experiments and extends …

Ambient Facile Synthesis Of Gram-Scale Copper Selenide Nanostructures From Commercial Copper And Selenium Powder, Xinqi Chen, Zhen Li, S X. Dou

Australian Institute for Innovative Materials - Papers

Grams of copper selenides (Cu_2-xSe) were prepared from commercial copper and selenium powders in the presence of thiol ligands by a one-pot reaction at room temperature. The resultant copper selenides are a mixture of nanoparticles and their assembled nanosheets, and the thickness of nanosheets assembled is strongly dependent on the ratio of thiol ligand to selenium powder. The resultant Cu_2-xSe (0 ≤ x ≤ 0.25) nanostructures were treated with hydrazine solution to remove the surface ligands and then explored as a potential thermoelectric candidate in comparison with commercial copper selenide powders. The research provides a novel …

Back Matter

Journal of Digital Forensics, Security and Law

No abstract provided.

Our Global Commons, Brigham Daniels, James Salzman

BYU Law Review

No abstract provided.

The Tragicomedy Of The Commons, Brigham Daniels

BYU Law Review

Scholarship on the commons focuses on a diverse set of problems, ranging from crashing fisheries to crowded court dockets. Because we find commons resources throughout our natural and cultural environments, understanding old lessons and learning new ones about the commons gives us leverage to address a wide range of problems. Because the list of resources identified as commons resources continues to grow, the importance of gleaning lessons about the commons will also continue to grow.

That being said, while the resources that make up the commons are certainly diverse, so too are the ways scholars depict it and the challenges …

Isolated Wetland Commons And The Constitution, Blake Hudson, Mike Hardig

BYU Law Review

Isolated wetlands provide great ecological and economic value to the United States. While some states provide protection for isolated wetlands, a great many do not. These wetlands are also left outside the ambit of federal wetland regulatory protections under the Clean Water Act, with its murky jurisdictional reach. Notwithstanding jurisdictional questions under current federal statutes, the U.S. Supreme Court has gone so far as to call into question the constitutionality of federal isolated wetland regulation. This Article makes a normative argument that, in the absence of state or local programs providing holistic isolated wetland protection, federal action is needed. The …

Agglomerama, Lee Anne Fennell

BYU Law Review

No abstract provided.

Local Governments And Global Commons, Jonathan Rosenbloom

BYU Law Review

No abstract provided.

Gauge Transformations Of The Biconformal Connection, James Thomas Wheeler

All Physics Faculty Publications

We study the changes of the biconformal gauge fields under the local rotational and dilatational gauge transformations.

Texas Groundwater And Tragically Stable “Crossovers”, Zachary Bray

BYU Law Review

One recurring question in the academic literature on common-pool resources relates to the persistence of “tragic” commons regimes—systems that encourage, or at least tolerate, the inefficient, wasteful, hazardous, or unfair exploitation of a resource that is easily accessed for and diminished by individual use and consumption. Of course, not all commons are tragic: some common-pool resources invite individual access in efficient, fair, and durable ways. Yet many commonly held resources do lie under systems of governance that are not just tragic but persistently and stubbornly so. Often the tragic aspects of such commons regimes are well known; indeed, for some …

Naming The Tragedy, Eric T. Freyfogle

BYU Law Review

No abstract provided.

Drip - Data Rich, Information Poor: A Concise Synopsis Of Data Mining, Muhammad Obeidat, Max North, Lloyd Burgess, Sarah North

Faculty and Research Publications

As production of data is exponentially growing with a drastically lower cost, the importance of data mining required to extract and discover valuable information is becoming more paramount. To be functional in any business or industry, data must be capable of supporting sound decision-making and plausible prediction. The purpose of this paper is concisely but broadly to provide a synopsis of the technology and theory of data mining, providing an enhanced comprehension of the methods by which massive data can be transferred into meaningful information.

U.S. Drought Monitor, December 30, 2014, Brad Rippey

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for December 30, 2014 (12/30/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.

Inductive Measurement Of Optically Hyperpolarized Phosphorous Donor Nuclei In An Isotopically Enriched Silicon-28 Crystal, P. Gumann, O. Patange, C. Ramanathan, H. Haas

Dartmouth Scholarship

We experimentally demonstrate the first inductive readout of optically hyperpolarized phosphorus-31 donor nuclear spins in an isotopically enriched silicon-28 crystal. The concentration of phosphorus donors in the crystal was 1.5×1015  cm−3, 3 orders of magnitude lower than has previously been detected via direct inductive detection. The signal-to-noise ratio measured in a single free induction decay from a 1  cm3 sample (≈1015 spins) was 113. By transferring the sample to an X-band ESR spectrometer, we were able to obtain a lower bound for the nuclear spin polarization at 1.7 K of ∼64%. The 31P-T2 measured with a Hahn echo sequence was …

Unidirectional Spectral Singularities, Hamidreza Ramezani, Hao Kun Li, Yuan Wang, Xiang Zhang

Physics and Astronomy Faculty Publications and Presentations

We propose a class of spectral singularities emerging from the coincidence of two independent singularities with highly directional responses. These spectral singularities result from resonance trapping induced by the interplay between parity-time symmetry and Fano resonances. At these singularities, while the system is reciprocal in terms of a finite transmission, a simultaneous infinite reflection from one side and zero reflection from the opposite side can be realized.

Momentum Distributions For 2H (E, E' P), William P. Ford, Sabine Jeschonnek, J. W. Van Orden

Faculty Publications

Background: A primary goal of deuteron electrodisintegration is the possibility of extracting the deuteron momentum distribution. This extraction is inherently fraught with difficulty, as the momentum distribution is not an observable and the extraction relies on theoretical models dependent on other models as input.

Purpose: We present a new method for extracting the momentum distribution which takes into account a wide variety of model inputs thus providing a theoretical uncertainty due to the various model constituents. To test the extraction, pseudodata were generated, and the extracted “experimental” distribution, which has theoretical uncertainty accounted by this extraction method, can be compared …

In Search Of The X2Bo And X2Bs (X = H, F) Free Radicals: Ab Initio Studies Of Their Spectroscopic Signatures, Dennis J. Clouthier

Chemistry Faculty Publications

The F₂BO free radical is a known, although little studied, species but similar X₂BY (X = H, D, F; Y = O, S) molecules are largely unknown. High level ab initio methods have been used to predict the molecular structures, vibrational frequencies (in cm^-1), and relative energies of the ground and first two excited electronic states of these free radicals, as an aid to their eventual spectroscopic identification. The chosen theoretical methods and basis sets were tested on F₂BO and found to give good agreement with the known experimental quantities. In particular, …

Chalcogen Bonds In Complexes Of Soxy (X, Y = F, Cl) With Nitrogen Bases, Luis Miguel Azofra, Ibon Alkorta, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

SOF2, SOFCl, and SOCl2 were each paired with a series of N bases. The potential energy surface of the binary complexes were characterized by MP2 calculations with double and triple-ξ basis sets, extrapolated to complete sets. The most stable configurations contained a S···N chalcogen bond with interaction energies as high as 6.8 kcal/mol. These structures are stabilized by a Nlp→σ*(S−Z) electron transfer (Z = O, F, Cl), complemented by Coulombicattraction of N to theσ-hole opposite the Z atom. N···S−F and N···S−Cl chalcogen bonds are stronger than N···S = O interactions.Formation of each chalcogen bond elongates all of the internalcovalent bonds …

Sulfur Vacancies In Photorefractive Sn2P2S6 Crystals, Eric M. Golden, Sergey A. Basun, A. A. Grabar, I. M. Stoika, Nancy C. Giles, D. R. Evans, Larry E. Halliburton

Faculty Publications

A photoinduced electron paramagnetic resonance (EPR) spectrum in single crystals of Sn2P2S6 (SPS) is assigned to an electron trapped at a sulfur vacancy. These vacancies are unintentionally present in undoped SPS crystals and are expected to play an important role in the photorefractive behavior of the material. Nonparamagnetic sulfur vacancies are formed during the initial growth of the crystal. Subsequent illumination below 100 K with 442 nm laser light easily converts these vacancies to EPR-active defects. The resulting S = 1/2 spectrum shows well-resolved and nearly isotropic hyperfine interactions with two P ions and two Sn ions. Partially resolved interactions …

Investigation Of Emic Wave Scattering As The Cause For The Barrel 17 January 2013 Relativistic Electron Precipitation Event: A Quantitative Comparison Of Simulation With Observations, Zan Li, Robyn M. Millan, Mary K. Hudson, Leslie A. Woodger, David M. Smith, Yue Chen, R. Friedel, J. V. Rodriguez, Mark J. Engebretson, J. Goldstein, Joseph F. Fennell, Harlan E. Spence

Physics & Astronomy

Abstract

Electromagnetic ion cyclotron (EMIC) waves were observed at multiple observatory locations for several hours on 17 January 2013. During the wave activity period, a duskside relativistic electron precipitation (REP) event was observed by one of the Balloon Array for Radiation belt Relativistic Electron Losses (BARREL) balloons and was magnetically mapped close to Geostationary Operational Environmental Satellite (GOES) 13. We simulate the relativistic electron pitch angle diffusion caused by gyroresonant interactions with EMIC waves using wave and particle data measured by multiple instruments on board GOES 13 and the Van Allen Probes. We show that the count rate, the energy …

Direct Electrochemistry And Glucose Biosensing Of Glucose Oxidase-Gold Nanoparticles Composite Synthesized By Enzyme Method, Fang He, Xiao-Li Qin, Ying-Chun Fu, Chao Chen, Qing-Ji Xie, Shou-Zhuo Yao

Journal of Electrochemistry

Glucose oxidase (GOx)-gold nanoparticles (AuNPs) composite was synthesized by the one-pot enzyme reaction in the mixture solution of NaAuCl₄, GOx and glucose, and a Nafion/GOx-AuNPs/glassy carbon electrode was fabricated by the cast-coating method to examine the direct electrochemistry of GOx and the biosensing performance on this electrode. Such a GOx-AuNPs composite showed good direct-electrochemistry activity and bioactivity of GOx, probably because the enzyme-mediated AuNPs are close to the redox active centers of GOx. This enzyme electrode exhibited a linear amperometric response to glucose concentration (0.54 mmol·L^-1) at -0.4 V (vs. SCE), and a detection limit of …

Electrochemiluminescence Imaging Focusing: Array Analysis And Visualization Of Latent Fingerprints, Zhen-Yu Zhou, Lin-Ru Xu, Bin Su

Journal of Electrochemistry

Electrochemiluminescence (ECL) imaging, as a novel and powerful analytical method, possesses many distinct advantages, including simplicity, high controllability, high-throughput and visualization. In recent years, it has been used in developing portable and miniaturized ECL sensor, and made remarkable achievements. In this review, the progress of ECL imaging, focusing on array analysis and visualization of latent fingerprints, has been introduced briefly based on our recent investigations and an attempt has been made to propose the future research trend.

Enzyme-Based Dna Electrochemical Biosensors: Recent Trends, Chun-Shui Lin, Yi-Ru Wang, Xi Chen

Journal of Electrochemistry

DNA electrochemical sensors have greatly promoted the development of biosensors for their high sensitivity, good selectivity, short analysis time and low cost. To further improve the detection sensitivity and selectivity, protein enzymes, functional nucleic acid enzymes etc. are often used due to the advantages of high catalytic efficiency and specificity. This review demonstrates the research progress of electrochemical sensors based on enzymatic amplification and analyses some existing problems of electrochemical sensors.

Synthesis Of Namnpo4 By Spraying Drying-High Temperature Sintering And Its Electrochemical Performance, Xiao-Chen Lin, Xiao-Biao Wu, Xu Hou, Yong Yang

Journal of Electrochemistry

As a cathode material for sodium ion batteries, NaMnPO₄/C nanocomposite is successfully synthesized by the combination of spraying drying and high temperature sintering methods. The crystal structure of the as-synthesized phosphate material is confirmed as the natrophilite NaMnPO₄, which possesses orthorhombic symmetry and Pmnb space group. It is shown that the precursors are hollow spherical particles and the obtained product consists of micro-scaled secondary particles, which are composed of NaMnPO₄ nanocrystallites (tens of nanometres) and amorphous carbon networks. The ionic and electronic conductivities of NaMnPO₄ are both effectively enhanced with the help of this …

Kinetics And Mechanism Of Acidic Electroless Ni-P Plating, Zhi-Hui Xie, Gang Yu

Journal of Electrochemistry

Electrochemical behaviors of electroless nickel (EN) plating in three systems, namely, cathodic, anodic and complete bath solutions were investigated by polarization methods. The curves in the complete baths were not entirely consistent with those expected from a combination of the anodic and cathodic polarization curves, which implies that the anodic and cathodic reactions of the EN plating are interdependent. The effects of concentration of nickel ions, hypophosphite and pH on the polarization parameter and deposition rate in a complete bath were also discussed and compared by performing electrochemical and gravimetrical measurements. Based on these variations in the deposition potential and …