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160670 full-text articles. Page 4026 of 4034.

Oxidative Destruction Of Chlorinated Hydrocarbons On Pt-Containing Fiber-Glass Catalysts, Eugene Paukshtis, Liudmila Simonova, Andrey Zagoruiko, Bair Balzhinimaev 2009 Boreskov Institute of Catalysis SB RAS

Oxidative Destruction Of Chlorinated Hydrocarbons On Pt-Containing Fiber-Glass Catalysts, Eugene Paukshtis, Liudmila Simonova, Andrey Zagoruiko, Bair Balzhinimaev

Andrey N Zagoruiko

Novel catalysts comprising noble metals (Pt), supported on fiber-glass woven materials demonstrated efficient oxidation of different chlorinated hydrocarbons (chlorobenzene, dichloroethane, dichloropropane, butyl chloride) and industrial mixed chlorinated organic wastes into HCl, СО2 and Н2О at moderate temperatures without formation of highly toxic by-products (dioxins, phosgene, polychlorinated hydrocarbons, elemental chlorine). The highest oxidation activity and selectivity was observed for the platinum catalysts produced from fiber-glass supports with increased acidity and with additional introduction of promoting elements (such as Co, Mn and Cu). Long-term tests (more than 100 h) have shown no deactivation of the said catalysts. In combination with competitive catalyst ...


Physics And Chemistry Of Hot-Wire Chemical Vapor Deposition From Silane: Measuring And Modeling The Silicon Epitaxy Deposition Rate, Ina Martin, Charles Teplin, James Doyle, Howard Branz, Paul Stradins 2009 Macalester College

Physics And Chemistry Of Hot-Wire Chemical Vapor Deposition From Silane: Measuring And Modeling The Silicon Epitaxy Deposition Rate, Ina Martin, Charles Teplin, James Doyle, Howard Branz, Paul Stradins

James R. Doyle

No abstract provided.


International Diversification: A Copula Approach, Lorán Chollete, Victor De la Pena, Ching-Chih Lu 2009 Columbia University

International Diversification: A Copula Approach, Lorán Chollete, Victor De La Pena, Ching-Chih Lu

Lorán Chollete

No abstract provided.


Emisja Zanieczyszczeń Pyłowo-Gazowych Z Procesu Wypalania Półproduktów Grafitowych W Piecu Tunelowym, Marek Bogacki, Robert Oleniacz, Marian Mazur, Przemysław Szczygłowski 2009 AGH University o Science and Technology

Emisja Zanieczyszczeń Pyłowo-Gazowych Z Procesu Wypalania Półproduktów Grafitowych W Piecu Tunelowym, Marek Bogacki, Robert Oleniacz, Marian Mazur, Przemysław Szczygłowski

Robert Oleniacz

The baking of semi-finished graphite products in a tunnel furnace is the source of many air pollutants present in both the gaseous and solid phases. The goal of this study was to assess emission rates into the air of the substances such as: CO, NOx, SO2, H2S, CH4, aliphatic hydrocarbons up to C6, benzene and its homologues (BTEX), total dust and tar substances, and polycyclic aromatic hydrocarbons (PAHs) contained in the dust. The research showed a small time-dependence of the emission rates for the majority of the substances analysed, which is, to a large extent, a result of the long ...


Spatial J-Test: Some Monte Carlo Evidence, Gianfranco Piras, Nancy Lozano-Gracia 2009 Regional Research Institute, West Virginia University

Spatial J-Test: Some Monte Carlo Evidence, Gianfranco Piras, Nancy Lozano-Gracia

Gianfranco Piras

No abstract provided.


Removal Of Perchlorate (Clo4-) From Water Using Pulsed Arc Electrohydraulic Discharge (Paed), Sarah Dickson 2009 Selected Works

Removal Of Perchlorate (Clo4-) From Water Using Pulsed Arc Electrohydraulic Discharge (Paed), Sarah Dickson

Sarah E Dickson

No abstract provided.


How A Bayesian Might Estimate The Distribution Of Cronbach’S Alpha From Ordinal-Dynamic Scaled Data A Case Study Measuring Nursing Home Resident Quality Of Life, Byron Gajewski, Diane Boyle, Sarah Thompson 2009 University of Kansas Medical Center

How A Bayesian Might Estimate The Distribution Of Cronbach’S Alpha From Ordinal-Dynamic Scaled Data A Case Study Measuring Nursing Home Resident Quality Of Life, Byron Gajewski, Diane Boyle, Sarah Thompson

Byron J Gajewski

We demonstrate the utility of a Bayesian based approach for calculating intervals of Cronbach’s alpha from a psychological instrument having ordinal responses with a dynamic scale. A small number of response options on an instrument will cause traditional-based interval estimates to be biased. Ordinal-based solutions are problematic because there is no clear mechanism for handling the dynamic scale. One way to remedy the bias is to adjust with a Bayesian approach. The Bayesian approach adjusts the bias and allows theoretically simple calculations of Cronbach’s alpha and intervals. We demonstrate the calculations of the Bayesian approach while at the ...


Comparative Study On Open System Digestion And Microwave Assisted Digestion Methods For Metal Determination In Shrimp Sludge Compost, Nor Kartini Abu Bakar 2009 University of Malaya

Comparative Study On Open System Digestion And Microwave Assisted Digestion Methods For Metal Determination In Shrimp Sludge Compost, Nor Kartini Abu Bakar

Nor Kartini Binti Abu Bakar

The aim of this work was to evaluate two different digestion methods for the determination of the total concentration of metals (Zn, Cu, Cr, Ni, Pb and Cd) in shrimp sludge compost. The compost made from shrimp aquaculture sludge co-composted with organic materials (peat, crushed bark and manure) was used as an organic growing medium for crop. Open system digestion and microwave assisted digestion procedures were employed in sample preparation. Various combinations and volumes of hydrofluoric, nitric and hydrochloric acids were evaluated for the efficiency of both methods. A certified reference material (CRM 146) was used in the comparison of ...


Catalytic Innovation In Microfinance For Inclusive Growth: Insights From Sks Microfinance, Lakshmi Mohan, Devendra Potnis 2009 University of Tennessee, Knoxville

Catalytic Innovation In Microfinance For Inclusive Growth: Insights From Sks Microfinance, Lakshmi Mohan, Devendra Potnis

Devendra Potnis

Microfinance offers a means for reaching the poor who are left out of the formal financial sector. A fundamentally new way is needed to create a scalable and sustainable business model to meet this unmet need: a catalytic innovation. Our study focused on Swayam Krishi Sangam (SKS), an archetype of a catalytic innovator. The insights gained from our 3-year longitudinal study led to the proposed framework for a catalytic innovator encompassing five factors: customer focus on the poor and social entrepreneurship for the social mission. operational innovation, information technology, human capital management for scaling, and financial sustainability.

DOI: 10.1080 ...


Bayesian Inference For A Periodic Stochastic Volatility Model Of Intraday Electricity Prices, Michael Smith 2009 Melbourne Business School

Bayesian Inference For A Periodic Stochastic Volatility Model Of Intraday Electricity Prices, Michael Smith

Michael Stanley Smith

The Gaussian stochastic volatility model is extended to allow for periodic autoregressions (PAR) in both the level and log-volatility process. Each PAR is represented as a first order vector autoregression for a longitudinal vector of length equal to the period. The periodic stochastic volatility model is therefore expressed as a multivariate stochastic volatility model. Bayesian posterior inference is computed using a Markov chain Monte Carlo scheme for the multivariate representation. A circular prior that exploits the periodicity is suggested for the log-variance of the log-volatilities. The approach is applied to estimate a periodic stochastic volatility model for half-hourly electricity prices ...


Bacon: An Effective Way To Detect Outliers In Multivariate Data Using Stata (And Mata), Sylvain Weber 2009 University of Neuchâtel

Bacon: An Effective Way To Detect Outliers In Multivariate Data Using Stata (And Mata), Sylvain Weber

Sylvain Weber

Identifying outliers in multivariate data is computationally intensive. The bacon command, presented in this article, allows one to quickly identify outliers, even on large datasets of tens of thousands of observations. bacon constitutes an attractive alternative to hadimvo, the only other command available in Stata for the detection of outliers.


Stacking Blocks And Counting Permutations, Lara Pudwell 2009 Valparaiso University

Stacking Blocks And Counting Permutations, Lara Pudwell

Lara K. Pudwell

No abstract provided.


An Introduction To Optimal Control For Discrete Models With An Application To Disease Modeling, Wandi Ding, Suzanne Lenhart 2009 Middle Tennessee State University

An Introduction To Optimal Control For Discrete Models With An Application To Disease Modeling, Wandi Ding, Suzanne Lenhart

Wandi Ding

No abstract provided.


Teacher Quality Grant – (St. Catherines Sea Turtle Conservation Program), R. Vance, Gale Bishop 2009 Georgia Southern University

Teacher Quality Grant – (St. Catherines Sea Turtle Conservation Program), R. Vance, Gale Bishop

R. Kelly Vance

No abstract provided.


Trace Element Deposition On Mount Everest, W. Yeo, Samantha Langley - Turnbaugh 2009 University of Southern Maine

Trace Element Deposition On Mount Everest, W. Yeo, Samantha Langley - Turnbaugh

Samantha Langley - Turnbaugh

No abstract provided.


Determination Of Chlorofluorocarbon Apparent Ages In Groundwater From The West Side Of The Island Of Hawaii, Jacque Kelly, Craig Glenn 2009 Georgia Southern University

Determination Of Chlorofluorocarbon Apparent Ages In Groundwater From The West Side Of The Island Of Hawaii, Jacque Kelly, Craig Glenn

Jacque L. Kelly

Large quantities of nutrient-enriched groundwater are supplied to coastal west Hawaii via point-sourced and diffuse groundwater seepage sites as submarine groundwater discharge. These inputs are especially important given that they are the only freshwater source to the coastal zone due to the absence of perennial streams. It has been suggested that discharging groundwaters are less than 50 years old; yet, the apparent ages of these groundwaters have not been investigated, despite the copious water volumes discharging to the coastal zone. Apparent age data is crucial to fully understand nutrient transformations along groundwater flow paths and will help constrain groundwater residence ...


Statistical Criteria For Selecting The Optimal Number Of Untreated Subjects Matched To Each Treated Subject When Using Many-To-One Matching On The Propensity Score, Peter Austin 2009 Institute for Clinical Evaluative Sciences

Statistical Criteria For Selecting The Optimal Number Of Untreated Subjects Matched To Each Treated Subject When Using Many-To-One Matching On The Propensity Score, Peter Austin

Peter Austin

Propensity-score matching is increasingly being used to estimate the effects of treatments using observational data. In many-to-one (M:1) matching on the propensity score, M untreated subjects are matched to each treated subject using the propensity score. The authors used Monte Carlo simulations to examine the effect of the choice of M on the statistical performance of matched estimators. They considered matching 1–5 untreated subjects to each treated subject using both nearest-neighbor matching and caliper matching in 96 different scenarios. Increasing the number of untreated subjects matched to each treated subject tended to increase the bias in the estimated ...


Binary Tidal Disruption Radius, Eric Addison 2009 Utah State University

Binary Tidal Disruption Radius, Eric Addison

Eric Addison

An expression for the tidal disruption radius of a binary system is calculated.


An Exponential Polynomial Observer For Synchronization Of Chaotic Systems, Ricardo Aguilar-López, Rafael Martinez-Guerra, Juan L. Mata-Machuca 2009 Centro de Investigación y de Estudios Avanzados del I.P.N. (CINVESTAV-IPN)

An Exponential Polynomial Observer For Synchronization Of Chaotic Systems, Ricardo Aguilar-López, Rafael Martinez-Guerra, Juan L. Mata-Machuca

Ricardo Aguilar-López

In this paper, we consider the synchronization problem via nonlinear observer design. A new exponential polynomial observer for a class of nonlinear oscillators is proposed, which is robust against output noises. A sufficient condition for synchronization is derived analytically with the help of Lyapunov stability theory. The proposed technique has been applied to synchronize chaotic systems (Rikitake and Rossler systems) by means of numerical simulation.


Constituents Of Calamintha Ashei: Effects On Florida Sandhill Species, M. Menelaou, H. Henandez, F. Macias, Jeffrey Weidenhamer, G. Williamson, F. Fronczek, H. Fischer, N. Fischer 2009 Ashland University

Constituents Of Calamintha Ashei: Effects On Florida Sandhill Species, M. Menelaou, H. Henandez, F. Macias, Jeffrey Weidenhamer, G. Williamson, F. Fronczek, H. Fischer, N. Fischer

Jeffrey D. Weidenhamer

Chemical constituents of the perennial shrub Calamintha ashei have been characterized as part of our investigation of the allelopathic properties of this plant. Besides the known monoterpenes, (+)-evodone, (-)-calaminthone and (+)-desacetylcalaminthone, fresh aerial parts of C. ashei provided six new menthofurans, two new germacrane sesquiterpenes, and the six, known flavonoids: 5-desmethoxynobiletin, 5-hydroxy-6,7,8,4'-tetramethoxyflavone, 5,4'-dihydroxy-6,7,8,3'-tetramethoxyflavone, thymonin, 5,4'-dihydroxy-6,7-dimethoxyflavone and 6-hydroxy-7,3'-dimethoxyluteolin. The structures of the new compounds were elucidated by spectroscopic methods and comparison of their H-1 NMR spectra with those of structurally related compounds. The molecular structures of ...


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