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2013

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Articles 10231 - 10260 of 11462

Full-Text Articles in Physical Sciences and Mathematics

Seller Diversity On A Technology-Based Platform, Ruhai Wu, Mei Lin Jan 2013

Seller Diversity On A Technology-Based Platform, Ruhai Wu, Mei Lin

Research Collection School Of Computing and Information Systems

Managing a technology portfolio is one of the great challenges for sustained success, especially in high-technology industrieswhere technologies can be a major selling point. For engineers, this portfolio is more of a toolbox for solving design problems,but in large organizations there can be so many technologies used in different business areas that even the engineers may not beaware of all of them. When the same technologies are used in different types of products, knowledge about them can also begenerated by various groups within an organization. To improve the usefulness of a company's technology base, this paperproposes the use of a …


An Initial Study Of Automatic Curb Ramp Detection With Crowdsourced Verification Using Google Street View Images, Kotaro Hara, Jin Sun, Jonah Chazan, David Jacobs, Jin Froehlich Jan 2013

An Initial Study Of Automatic Curb Ramp Detection With Crowdsourced Verification Using Google Street View Images, Kotaro Hara, Jin Sun, Jonah Chazan, David Jacobs, Jin Froehlich

Research Collection School Of Computing and Information Systems

In our previous research, we examined whether minimallytrained crowd workers could find, categorize, and assesssidewalk accessibility problems using Google Street View(GSV) images. This poster paper presents a first step towardscombining automated methods (e.g., machine visionbasedcurb ramp detectors) in concert with human computationto improve the overall scalability of our approach.


"Molecular Spectroscopy And Dynamics Of Reactive Chemical Intermediates Studied Using Laser Induced Fluorescence (Lif), Single Vibronic Level (Svl) Emission And Resonance Enhanced Multiphoton Ionization (Rempi) Spectrometry.", Lloyd Godfrey Muzangwa Jan 2013

"Molecular Spectroscopy And Dynamics Of Reactive Chemical Intermediates Studied Using Laser Induced Fluorescence (Lif), Single Vibronic Level (Svl) Emission And Resonance Enhanced Multiphoton Ionization (Rempi) Spectrometry.", Lloyd Godfrey Muzangwa

Dissertations (1934 -)

ABSTRACT

"MOLECULAR SPECTROSCOPY AND DYNAMICS OF REACTIVE CHEMICAL INTERMEDIATES STUDIED USING LASER INDUCED FLUORESCENCE (LIF), SINGLE VIBRONIC LEVEL (SVL) EMISSION AND RESONANCE ENHANCED MULTIPHOTON IONIZATION (REMPI) SPECTROMETRY"

Lloyd Muzangwa, B.Sc. (Hons, Biochemistry).

Marquette University, 2013

In the studies of complex chemical processes, it is necessary to postulate mechanisms involving transient intermediates such as radicals, ions, and pre-reactive complexes. The detection and characterization of these intermediates affords in ideal cases determination of the detailed chemical mechanism, which, in turn, can permit the development of rational strategies for removing undesired products and enhancing the yield of the desired species. This dissertation describes …


Delineation And Characterization Of The Furnace Brook Watershed In Marshfield, Massachusetts: Potential Impact Of Water Supply Extraction, Erik Croll Jan 2013

Delineation And Characterization Of The Furnace Brook Watershed In Marshfield, Massachusetts: Potential Impact Of Water Supply Extraction, Erik Croll

Undergraduate Review

The Furnace Brook watershed in Marshfield, Massachusetts supplies a coastal community of 25,132 residents with nearly 45% of its town water supply (Marshfield 2012a). As in many other coastal communities, development pressure in Marshfield has increased in recent years, creating a growing demand for freshwater extraction. It has been observed, however, that portions of the stream and Furnace Pond disappear entirely at certain times of year, generally between June and August, depending on the rate of groundwater extraction. This has created a conflict between protecting the designated wetland areas and meeting public pressure for water resources, even within what is …


The Effect Of Hydrochloric Acid Strength On The Nanometer-Scale Dissolution Topography Of Calcite Crystal Surfaces, Jennifer Fruzzetti Jan 2013

The Effect Of Hydrochloric Acid Strength On The Nanometer-Scale Dissolution Topography Of Calcite Crystal Surfaces, Jennifer Fruzzetti

Undergraduate Review

The physico-chemical mechanisms by which rock-forming minerals dissolve in natural fluids are controlled by a number of environmental factors. In this study, we investigate dissolution mechanisms by observing how the nanometer-scale surface topography of calcite is affected by the acidity of etching solutions. Here we report atomic force microscope (AFM) observations of calcite crystal surfaces both before and after chemical etching for 10 seconds in 0.01%, 0.1%, and 1.0% HCl solutions. AFM observations show that unetched, freshly-cleaved calcite {10ī4} crystal surfaces are characterized by flat layers separated by steps oriented parallel to calcite cleavage planes. Calcite {10ī4} crystal surfaces etched …


Exploring Diagonals In The Calkin-Wilf Tree, Matthew Gagne Jan 2013

Exploring Diagonals In The Calkin-Wilf Tree, Matthew Gagne

Undergraduate Review

For centuries, people have been interested in patterns. Even in that which appears random, humans have been trying to understand the underlying order of things. Mathematicians throughout time have studied many phenomena, including infinite sequences of numbers and have been able, at times, to see structure. Many have found the satisfaction, even joy, of discovering patterns in sequences. A typical way to describe this is by a recursive formula. A recursive definition defines a term in the sequence using the previous terms in the sequence. Even more satisfying than a recursive formula is a closed formula. With this, one can …


Modeling Plaque Aggregation On The Neuronal Network, Thomas Howard Jan 2013

Modeling Plaque Aggregation On The Neuronal Network, Thomas Howard

Undergraduate Review

Alzheimer’s disease is a condition linked to plaque aggregation in the brain. Despite being the focus of many studies, current treatments are of questionable significance in the overall improvement of a patient’s condition. In recent years, computer models have been used to better understand complex biological systems and simulate the effects of various treatments. In the following paper we present a mathematical model studying the effects of plaque aggregation on the neuronal pathways of the human brain. To create our mathematical model we employ tools from the theory of dynamical systems and stochastic processes, and simulate the passage of a …


A Greener Disney, Cidalia Pina Jan 2013

A Greener Disney, Cidalia Pina

Undergraduate Review

Disney brings nature and environmental issues to the forefront with its non-confrontational approach to programming meant for children. This opportunity raises awareness and is relevant to growing environmental concerns. However this awareness is just a cursory start, there is an imbalance in their message and effort with that of their carbon footprint. The important eco-messages that Disney presents are buried in fantasy and unrealistic plots. As an entertainment giant with the world held magically captive, Disney can do more, both in filmmaking and as a corporation, to facilitate a greener planet.


Competition Between Software-As-A-Service Vendors, Robert J. Kauffman, Dan Ma Jan 2013

Competition Between Software-As-A-Service Vendors, Robert J. Kauffman, Dan Ma

Research Collection School Of Computing and Information Systems

No abstract provided.


How Strong Are The Effects Of Technological Disruption? Smartphones' Impacts On Internet And Cable Tv Services Consumption, M. R. Chang, Robert J. Kauffman, K.S. Kim Jan 2013

How Strong Are The Effects Of Technological Disruption? Smartphones' Impacts On Internet And Cable Tv Services Consumption, M. R. Chang, Robert J. Kauffman, K.S. Kim

Research Collection School Of Computing and Information Systems

Emerging technologies have created disruptions in organizational, business process and industry contexts. They act as shocks to a system. We focus on a retail telecom service provider’s offerings of different bun-dles, including mobile phones, Internet and cable TV services. We conduct empirical regularities analysis for Singapore, which was affected by the emergence of smartphones in 2009. We assess the impacts on the service bundle choices of a provider’s customers. We analyze customer switching among service bundles involving three services. We compute switching proba-bilities for each of the service levels offered, as well as between bundles. We use Markov chain transition …


Clustering Of Search Trajectory And Its Application To Parameter Tuning, Linda Lindawati, Hoong Chuin Lau, David Lo Jan 2013

Clustering Of Search Trajectory And Its Application To Parameter Tuning, Linda Lindawati, Hoong Chuin Lau, David Lo

Research Collection School Of Computing and Information Systems

This paper is concerned with automated classification of Combinatorial Optimization Problem instances for instance-specific parameter tuning purpose. We propose the CluPaTra Framework, a generic approach to CLUster instances based on similar PAtterns according to search TRAjectories and apply it on parameter tuning. The key idea is to use the search trajectory as a generic feature for clustering problem instances. The advantage of using search trajectory is that it can be obtained from any local-search based algorithm with small additional computation time. We explore and compare two different search trajectory representations, two sequence alignment techniques (to calculate similarities) as well as …


Multimedia Recommendation: Technology And Techniques, Jialie Shen, Meng Wang, Shuicheng Yan, Peng Cui Jan 2013

Multimedia Recommendation: Technology And Techniques, Jialie Shen, Meng Wang, Shuicheng Yan, Peng Cui

Research Collection School Of Computing and Information Systems

In recent years, we have witnessed a rapid growth in the availability of digital multimedia on various application platforms and domains. Consequently, the problem of information overload has become more and more serious. In order to tackle the challenge, various multimedia recommendation technologies have been developed by different research communities (e.g., multimedia systems, information retrieval, machine learning and computer version). Meanwhile, many commercial web systems (e.g., Flick, YouTube, and Last.fm) have successfully applied recommendation techniques to provide users personalized content and services in a convenient and flexible way. When looking back, the information retrieval (IR) community has a long history …


Hypergraph Index: An Index For Context-Aware Nearest Neighbor Query On Social Networks, Yazhe Wang, Baihua Zheng Jan 2013

Hypergraph Index: An Index For Context-Aware Nearest Neighbor Query On Social Networks, Yazhe Wang, Baihua Zheng

Research Collection School Of Computing and Information Systems

Social network has been touted as the No. 2 innovation in a recent IEEE Spectrum Special Report on “Top 11 Technologies of the Decade”, and it has cemented its status as a bona fide Internet phenomenon. With more and more people starting using social networks to share ideas, activities, events, and interests with other members within the network, social networks contain a huge amount of content. However, it might not be easy to navigate social networks to find specific information. In this paper, we define a new type of queries, namely context-aware nearest neighbor (CANN) search over social network to …


Improving Internet Security Through Information Disclosure: A Field Quasi-Experiment, Qian Tang, Leigh L. Linden, John S. Quarterman, Andrew B. Whinston Jan 2013

Improving Internet Security Through Information Disclosure: A Field Quasi-Experiment, Qian Tang, Leigh L. Linden, John S. Quarterman, Andrew B. Whinston

Research Collection School Of Computing and Information Systems

Cybersecurity is a national priority in this big data era. Because of negative externalities and the resulting lack of economic incentives, companies often underinvest in security controls, despite government and industry recommendations. Although many existing studies on security have explored technical solutions, only a few have looked at the economic motivations. To fill the gap, we propose an approach to increase the incentives of organizations to address security problems. Specifically, we utilize and process existing security vulnerability data, derive explicit security performance information, and disclose the information as feedback to organizations and the public. We regularly release information on the …


A Secure Platform For Information Sharing In Epcglobal Network, Jie Shi, Yingjiu Li, Robert H. Deng, Wei He, Eng Wah Lee Jan 2013

A Secure Platform For Information Sharing In Epcglobal Network, Jie Shi, Yingjiu Li, Robert H. Deng, Wei He, Eng Wah Lee

Research Collection School Of Computing and Information Systems

With the rapid development of RFID technology, the EPCglobal network has drawn considerable attention from both research and industry communities, which enables supply chain partners to automatically share information and improve the visibility of supply chains. As the information shared in the EPCglobal network is usually sensitive and valuable, security mechanisms should be provided. In this paper, we aim at designing and implementing a secure information sharing platform in the EPCglobal network with a focus on authorization mechanism. We also design and implement a track and trace application based on the proposed secure platform so as to demonstrate its feasibility …


Decision Support For Assorted Populations In Uncertain And Congested Environments, Pradeep Reddy Varakantham, Asrar Ahmed, Shih-Fen Cheng Jan 2013

Decision Support For Assorted Populations In Uncertain And Congested Environments, Pradeep Reddy Varakantham, Asrar Ahmed, Shih-Fen Cheng

Research Collection School Of Computing and Information Systems

This research is motivated by large scale problems in urban transportation and labor mobility where there is congestion for resources and uncertainty in movement. In such domains, even though the individual agents do not have an identity of their own and do not explicitly interact with other agents, they effect other agents. While there has been much research in handling such implicit effects, it has primarily assumed deterministic movements of agents. We address the issue of decision support for individual agents that are identical and have involuntary movements in dynamic environments. For instance, in a taxi fleet serving a city, …


Special Issue On Plenary And Invited Papers From Icops 2012, Felipe Iza, Carl Ekdahl, Michael G. Kong Jan 2013

Special Issue On Plenary And Invited Papers From Icops 2012, Felipe Iza, Carl Ekdahl, Michael G. Kong

Electrical & Computer Engineering Faculty Publications

The 39th International Conference on Plasma Science (ICOPS) was held in Edinburgh, Scotland in July 2012. This was the third time that the conference was organized outside North America, the previous ones being in Karlsruhe (Germany) in 2008 and Jeju (S. Korea) in 2003. The technical programme combined seven technical areas of plasma science and technology covering a wide range of topics. The conference featured a wide range of advances in innovative plasma and beam science and applications, and served as a venue for an international community to meet and discuss their ideas and research results. More than 800 abstracts …


Observations Of Peroxyacetyl Nitrate (Pan) In The Upper Troposphere By The Atmospheric Chemistry Experiment-Fourier Transform Spectrometer (Ace-Fts), K. A. Tereszchuk, D. P. Moore, J. J. Harrison, C. D. Boone, M. Park, J. J. Remedios, W. J. Randel, P. F. Bernath Jan 2013

Observations Of Peroxyacetyl Nitrate (Pan) In The Upper Troposphere By The Atmospheric Chemistry Experiment-Fourier Transform Spectrometer (Ace-Fts), K. A. Tereszchuk, D. P. Moore, J. J. Harrison, C. D. Boone, M. Park, J. J. Remedios, W. J. Randel, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

Peroxyacetyl nitrate (CH3CO·O2NO2, abbreviated as PAN) is a trace molecular species present in the troposphere and lower stratosphere due primarily to pollution from fuel combustion and the pyrogenic outflows from biomass burning. In the lower troposphere, PAN has a relatively short lifetime and is principally destroyed within a few hours through thermolysis, but it can act as a reservoir and carrier of NOx in the colder temperatures of the upper troposphere, where UV photolysis becomes the dominant loss mechanism. Pyroconvective updrafts from large biomass burning events can inject PAN into the upper troposphere …


Ace-Fts Observations Of Pyrogenic Trace Species In Boreal Biomass Burning Plumes During Bortas, K. A. Tereszchuk, G. G. Abad, C. Clerbaux, J. Hadji-Lazaro, D. Hurtmans, P. F. Coheur, P. F. Bernath Jan 2013

Ace-Fts Observations Of Pyrogenic Trace Species In Boreal Biomass Burning Plumes During Bortas, K. A. Tereszchuk, G. G. Abad, C. Clerbaux, J. Hadji-Lazaro, D. Hurtmans, P. F. Coheur, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

To further our understanding of the effects of biomass burning emissions on atmospheric composition, the BORTAS campaign (BOReal forest fires on Tropospheric oxidants over the Atlantic using Aircraft and Satellites) was conducted on 12 July to 3 August 2011 during the boreal forest fire season in Canada. The simultaneous aerial, ground and satellite measurement campaign sought to record instances of boreal biomass burning to measure the tropospheric volume mixing ratios (VMRs) of short- and long-lived trace molecular species from biomass burning emissions. The goal was to investigate the connection between the composition and the distribution of these pyrogenic outflows and …


Hci And Cio Profiles Inside The Antarctic Vortex As Observed By Smiles In November 2009: Comparisons With Mls And Ace-Fts Instruments, T. Sugita, Y. Kasai, Y. Terao, S. Hayashida, G. L. Manney, W. H. Daffer, H. Sagawa, M. Suzuki, M. Shiotani, K. A. Walker, C. D. Boone, P. F. Bernath Jan 2013

Hci And Cio Profiles Inside The Antarctic Vortex As Observed By Smiles In November 2009: Comparisons With Mls And Ace-Fts Instruments, T. Sugita, Y. Kasai, Y. Terao, S. Hayashida, G. L. Manney, W. H. Daffer, H. Sagawa, M. Suzuki, M. Shiotani, K. A. Walker, C. D. Boone, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

We present vertical profiles of hydrogen chloride (HCl) and chlorine monoxide (ClO) as observed by the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) on the International Space Station (ISS) inside the Antarctic vortex on 19-24 November 2009. The SMILES HCl value reveals 2.8-3.1 ppbv between 450K and 500K levels in potential temperature (PT). The high value of HCl is highlighted since it is suggested that HCl is a main component of the total inorganic chlorine Cly, defined as Cly similar or equal to HCl + ClO + chlorine nitrate ClONO2, inside the Antarctic vortex in spring, owing …


Investigation Of Co, C2h6 And Aerosols In A Boreal Fire Plume Over Eastern Canada During Bortas 2011 Using Ground- And Satellite-Based Observations And Model Simulations, D. Griffin, K. A. Walker, J. E. Franklin, M. Parrington, C. Whaley, J. Hopper, J. R. Drummond, P. I. Palmer, K. Strong, T. J. Duck, P. F. Bernath Jan 2013

Investigation Of Co, C2h6 And Aerosols In A Boreal Fire Plume Over Eastern Canada During Bortas 2011 Using Ground- And Satellite-Based Observations And Model Simulations, D. Griffin, K. A. Walker, J. E. Franklin, M. Parrington, C. Whaley, J. Hopper, J. R. Drummond, P. I. Palmer, K. Strong, T. J. Duck, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

We present the results of total column measurements of CO, C2H6 and fine-mode aerosol optical depth (AOD) during the "Quantifying the impact of BOReal forest fires on Tropospheric oxidants over the Atlantic using Aircraft and Satellites" (BORTAS-B) campaign over eastern Canada. Ground-based observations, using Fourier transform spectrometers (FTSs) and sun photometers, were carried out in July and August 2011. These measurements were taken in Halifax, Nova Scotia, which is an ideal location to monitor the outflow of boreal fires from North America, and also in Toronto, Ontario. Measurements of fine-mode AOD enhancements were …


Ace-Fts Observations Of Acetonitrile In The Lower Stratosphere, J. J. Harrison, P. F. Bernath Jan 2013

Ace-Fts Observations Of Acetonitrile In The Lower Stratosphere, J. J. Harrison, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

This work reports the first infrared satellite remote-sensing measurements of acetonitrile (CH3CN) in the Earth's atmosphere using solar occultation measurements made by the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) between 2004 and 2011. The retrieval scheme uses new quantitative laboratory spectroscopic measurements of acetonitrile (Harrison and Bernath, 2012). Although individual ACE-FTS profile measurements are dominated by measurement noise, median profiles in 10 degrees latitude bins show a steady decline in volume mixing ratio from similar to 150 ppt (parts per trillion) at 11.5 km to < 40 ppt at 25.5-29.5 km. These new measurements agree well with the scant available air-and balloon-borne data in the lower stratosphere. An acetonitrile stratospheric lifetime of 73 ± 20 yr has been determined.


The Roles Of Vertical Advection And Eddy Diffusion In The Equatorial Mesospheric Semi-Annual Oscillation (Msao), R. L. Gattinger, E. Kyrölä, C. D. Boone, W. F.J. Evans, K. A. Walker, I. C. Mcdade, P. F. Bernath, E. J. Llewellyn Jan 2013

The Roles Of Vertical Advection And Eddy Diffusion In The Equatorial Mesospheric Semi-Annual Oscillation (Msao), R. L. Gattinger, E. Kyrölä, C. D. Boone, W. F.J. Evans, K. A. Walker, I. C. Mcdade, P. F. Bernath, E. J. Llewellyn

Chemistry & Biochemistry Faculty Publications

Observations of the mesospheric semi-annual oscillation (MSAO) in the equatorial region have been reported dating back several decades. Seasonal variations in both species densities and airglow emissions are well documented. The extensive observations available offer an excellent case study for comparison with model simulations. A broad range of MSAO measurements is summarised with emphasis on the 80-100 km region. The objective here is not to address directly the complicated driving forces of the MSAO, but rather to employ a combination of observations and model simulations to estimate the limits of some of the underlying dynamical processes. Photochemical model simulations are …


Validation Of Stratospheric And Mesospheric Ozone Observed By Smiles From International Space Station, Y. Kasai, H. Sagawa, D. Kreyling, E. Dupuy, P. Baron, J. Mendrok, K Suzuki, T. O. Sato, T. Nishibori, S. Mizobuchi, P. F. Bernath Jan 2013

Validation Of Stratospheric And Mesospheric Ozone Observed By Smiles From International Space Station, Y. Kasai, H. Sagawa, D. Kreyling, E. Dupuy, P. Baron, J. Mendrok, K Suzuki, T. O. Sato, T. Nishibori, S. Mizobuchi, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

We observed ozone O3 in the vertical region between 250 and 0.0005 hPa (~ 12-96 km) using the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) on the Japanese Experiment Module (JEM) of the International Space Station (ISS) between 12 October 2009 and 21 April 2010. The new 4K superconducting heterodyne receiver technology of SMILES allowed us to obtain a one order of magnitude better signal-to-noise ratio for the O3 line observation compared to past spaceborne microwave instruments. The non-sun-synchronous orbit of the ISS allowed us to observe O3 at various local times. We assessed the quality of the vertical …


Hydrocarbons In The Upper Troposphere And Lower Stratosphere Observed From Ace-Fts And Comparisons With Waccm, Mijeong Park, William J. Randel, Douglas E. Kinnison, Louisa K. Emmons, Peter F. Bernath, Kaley A. Walker, Chris D. Boone, Nathaniel J. Livesey Jan 2013

Hydrocarbons In The Upper Troposphere And Lower Stratosphere Observed From Ace-Fts And Comparisons With Waccm, Mijeong Park, William J. Randel, Douglas E. Kinnison, Louisa K. Emmons, Peter F. Bernath, Kaley A. Walker, Chris D. Boone, Nathaniel J. Livesey

Chemistry & Biochemistry Faculty Publications

Satellite measurements from the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) are used to examine the global, seasonal variations of several hydrocarbons, including carbon monoxide (CO), ethane (C2H6), acetylene (C2H2), and hydrogen cyanide (HCN). We focus on quantifying large-scale seasonal behavior from the middle troposphere to the stratosphere, particularly in the tropics, and furthermore make detailed comparisons with the Whole Atmosphere Community Climate Model (WACCM) chemistry climate model (incorporating tropospheric photochemistry, time-varying hydrocarbon emissions, and meteorological fields nudged from reanalysis). Comparisons with Microwave Limb Sounder (MLS) measurements of CO are also included …


The Relation Between Atmospheric Humidity And Temperature Trends For Stratospheric Water, S. Fueglistaler, Y. S. Liu, T. J. Flannaghan, P. H. Haynes, D. P. Dee, W. J. Read, E. E. Remsberg, L. W. Thomason, D. F. Hurst, J. R. Lanzante, P. F. Bernath Jan 2013

The Relation Between Atmospheric Humidity And Temperature Trends For Stratospheric Water, S. Fueglistaler, Y. S. Liu, T. J. Flannaghan, P. H. Haynes, D. P. Dee, W. J. Read, E. E. Remsberg, L. W. Thomason, D. F. Hurst, J. R. Lanzante, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

We analyze the relation between atmospheric temperature and water vapor-a fundamental component of the global climate system-for stratospheric water vapor (SWV). We compare measurements of SWV (and methane where available) over the period 1980-2011 from NOAA balloon-borne frostpoint hygrometer (NOAA-FPH), SAGE II, Halogen Occultation Experiment (HALOE), Microwave Limb Sounder (MLS)/Aura, and Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS) to model predictions based on troposphere-to-stratosphere transport from ERA-Interim, and temperatures from ERA-Interim, Modern Era Retrospective- Analysis (MERRA), Climate Forecast System Reanalysis (CFSR), Radiosonde Atmospheric Temperature Products for Assessing Climate (RATPAC), HadAT2, and RICHv1.5. All model predictions are dry biased. The interannual …


Production Mechanisms, Number Concentration, Size Distribution, Chemical Composition, And Optical Properties Of Sea Spray Aerosols, Nicholas Meskhidze, Markus D. Petters, Kostas Tsigaridis, Tim Bates, Colin O'Dowd, Jeff Reid, Ernie R. Lewis, Brett Gantt, Magdalena D. Anguelova, Prakash V. Bhave, Andrew Wozniak Jan 2013

Production Mechanisms, Number Concentration, Size Distribution, Chemical Composition, And Optical Properties Of Sea Spray Aerosols, Nicholas Meskhidze, Markus D. Petters, Kostas Tsigaridis, Tim Bates, Colin O'Dowd, Jeff Reid, Ernie R. Lewis, Brett Gantt, Magdalena D. Anguelova, Prakash V. Bhave, Andrew Wozniak

Chemistry & Biochemistry Faculty Publications

(First paragraph)

The impact of sea spray aerosols on global climate remains one of the most uncertain components of the aerosol–radiation–climate problem, but has received less attention than the impacts of terrestrial and anthropogenic aerosols. The last decade has produced a large body of information regarding the sources and composition of marine aerosols, resulting in a reassessment of the complex role that sea spray particles play in climate and various geophysical phenomena. As sea spray aerosol contributes substantially to the preindustrial, natural background which provides the baseline on top of which anthropogenic forcing should be quantified, and because the ocean …


Iupac Critical Evaluation Of The Rotational-Vibrational Spectra Of Water Vapor, Part Iii: Energy Levels And Transition Wavenumbers For H216o, Jonathan Tennyson, Peter F. Bernath, Linda R. Brown, Alain Campargue, Attila G. Csaszar, Ludovic Daumont, Robert R. Gamache, Joseph T. Hodges, Olga V. Naumenko, Oleg L. Polyansky Jan 2013

Iupac Critical Evaluation Of The Rotational-Vibrational Spectra Of Water Vapor, Part Iii: Energy Levels And Transition Wavenumbers For H216o, Jonathan Tennyson, Peter F. Bernath, Linda R. Brown, Alain Campargue, Attila G. Csaszar, Ludovic Daumont, Robert R. Gamache, Joseph T. Hodges, Olga V. Naumenko, Oleg L. Polyansky

Chemistry & Biochemistry Faculty Publications

This is the third of a series of articles reporting critically evaluated rotational-vibrational line positions, transition intensities, and energy levels, with associated critically reviewed labels and uncertainties, for all the main isotopologues of water. This paper presents experimental line positions, experimental-quality energy levels, and validated labels for rotational-vibrational transitions of the most abundant isotopologue of water, H216O. The latest version of the MARVEL (Measured Active Rotational-Vibrational Energy Levels) line-inversion procedure is used to determine the rovibrational energy levels of the electronic ground state of H216O from experimentally measured lines, together with their self-consistent uncertainties, …


Role Of Extractable And Residual Organic Matter Fractions On Sorption Of Phenanthrene In Sediments, Yulong Zhang, Yong Ran, Jingdong Mao Jan 2013

Role Of Extractable And Residual Organic Matter Fractions On Sorption Of Phenanthrene In Sediments, Yulong Zhang, Yong Ran, Jingdong Mao

Chemistry & Biochemistry Faculty Publications

Two sediments were demineralized and sequentially fractionated into extracted fractions [free lipid (FL), bound lipid (BL) and lignin (LG)] and residual fractions [free lipid free (FLF), bound lipid free (BLF) and lignin free (LGF)]. The sorption isotherms of phenanthrene (Phen) were examined to evaluate the importance of various fractions on sorption. A lignin extraction procedure was for the first time applied to separate the lignin or degraded lignin fraction from sediment organic matter (SOM). The extracted LG was similar to model lignin in terms of elemental ratios and sorption behavior. FL and LG fractions were quite important, as their contents …


A Preliminary Examination Of An In Situ Dual Dye Approach To Measuring Light Fluxes In Lotic Systems, Elizabeth C. Minor, Elizabeth James, Jay A. Austin, Veronica Nelson, Ryan Lusk, Kenneth Mopper Jan 2013

A Preliminary Examination Of An In Situ Dual Dye Approach To Measuring Light Fluxes In Lotic Systems, Elizabeth C. Minor, Elizabeth James, Jay A. Austin, Veronica Nelson, Ryan Lusk, Kenneth Mopper

Chemistry & Biochemistry Faculty Publications

Light is a critical parameter in aquatic ecosystems, affecting primary production and in situ photochemistry. However, measuring light exposure for suspended particles or dissolved components in a dynamic water column can be challenging with existing Eulerian approaches. Here, we assess the simultaneous deployment of two dyes differing in photolability (rhodamine WT and fluorescein) as a Lagrangian measure of sunlight exposure in a lotic system. Fluorescein is sensitive to light exposure; rhodamine WT is relatively photostable. We examined dye fluorescence at various pH, salinity, and temperature conditions. We also tested dye photolability as a function of pH and wavelength range. In …