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Thermodynamic Properties Of Thymus Satureioides Essential Oils As Corrosion Inhibitor Of Tinplate In 0.5 M Hcl:Chemical Characterization And Electrochemical Study, L. Bammou, B. Chebli, R. Salghi, L. Bazzi, B. Hammouti, M. Mihit, H. El Idrissi 2009 Ibn-Zohr University

Thermodynamic Properties Of Thymus Satureioides Essential Oils As Corrosion Inhibitor Of Tinplate In 0.5 M Hcl:Chemical Characterization And Electrochemical Study, L. Bammou, B. Chebli, R. Salghi, L. Bazzi, B. Hammouti, M. Mihit, H. El Idrissi

Mihit Mohammed Ph.D

Thymus satureioides (TS) oil was hydrodistillated and analyzed by chromatography. The natural oil was tested as a green inhibitor for tinplate in 0.5 M HCl solution. Electrochemical parameters of different concentrations of TS oil and the corresponding corrosion inhibition efficiencies were reported. Polarization data indicated that the studied oil acts as a mixed type inhibitor without changing the mechanism of hydrogen evolution reaction. The effect of temperature (25_608C) on the inhibition efficiency at different concentrations of the oil studied was investigated. The data revealed that the TS oil might exhibit good inhibition even at moderate to high temperatures. The ...


Links Between Analysis Of Surrogate Endpoints And Endogeneity, Debashis Ghosh, Jeremy Taylor, Michael Elliott 2009 Penn State University

Links Between Analysis Of Surrogate Endpoints And Endogeneity, Debashis Ghosh, Jeremy Taylor, Michael Elliott

Debashis Ghosh

There has been substantive interest in the assessment of surrogate endpoints in medical research. These are measures which could potentially replace \true" endpoints in clinical trials and lead to studies that require less follow-up. Recent research in the area has focused on assessments using causal inference frameworks. Beginning with a simple model for associating the surrogate and true endpoints in the population, we approach the problem as one of endogenous covariates. An instrumental variables estimator and general two-stage algorithm is proposed. Existing surrogacy frameworks are then evaluated in the context of the model. A numerical example is used to illustrate ...


Effect Of Halogen Ions On The Electrochemical Behaviour Of Lead In Hydrochloride Medium, M. Mihit, R. Salghi, L. Bazzi 2009 Ibn-Zohr University

Effect Of Halogen Ions On The Electrochemical Behaviour Of Lead In Hydrochloride Medium, M. Mihit, R. Salghi, L. Bazzi

Mihit Mohammed Ph.D

No abstract provided.


Voluntary Environmental Regulation In Developing Countries: Mexico's Clean Industry Program, William Pizer, Allen Blackman, Bidisha Lahiri, Marisol Rivera Planter, Carlos Muñoz Piña 2009 Duke University

Voluntary Environmental Regulation In Developing Countries: Mexico's Clean Industry Program, William Pizer, Allen Blackman, Bidisha Lahiri, Marisol Rivera Planter, Carlos Muñoz Piña

William Pizer

Because conventional command-and-control environmental regulation often performs poorly in developing countries, policymakers are increasingly experimenting with alternatives, including voluntary regulatory programs. Research in industrialized countries suggests that such programs are sometimes ineffective because they mainly attract relatively clean participants free-riding on unrelated pollution control investments. We use plant-level data on more than 100,000 facilities to analyze the Clean Industry Program, Mexico’s flagship voluntary regulatory initiative. We seek to identify the drivers of participation and to determine whether the program improves participants’ environmental performance. Using data from the program’s first decade, we find that plants recently fined by ...


List Coloring And N-Monophilic Graphs, Ramin Naimi, Radoslav Kirov 2009 Occidental College

List Coloring And N-Monophilic Graphs, Ramin Naimi, Radoslav Kirov

Ramin Naimi

In 1990, Kostochka and Sidorenko proposed studying the smallest number of list-colorings of a graph G among all assignments of lists of a given size n to its vertices. We say a graph G is n-monophilic if this number is minimized when identical n-color lists are assigned to all vertices of G. Kostochka and Sidorenko observed that all chordal graphs are n-monophilic for all n. Donner (1992) showed that every graph is n-monophilic for all sufficiently large n. We prove that all cycles are n-monophilic for all n; we give a complete characterization of 2-monophilic graphs (which turns out to ...


Gibbs Sampling For A Bayesian Hierarchical General Linear Model, Alicia Johnson, Galin Jones 2009 University of Minnesota - Twin Cities

Gibbs Sampling For A Bayesian Hierarchical General Linear Model, Alicia Johnson, Galin Jones

Alicia A. Johnson

No abstract provided.


Assessment Of The Impact Of Using Alternative Fuels In A Cement Kiln On The Emissions Of Selected Substances Into The Air, Robert Oleniacz 2009 AGH University o Science and Technology

Assessment Of The Impact Of Using Alternative Fuels In A Cement Kiln On The Emissions Of Selected Substances Into The Air, Robert Oleniacz

Robert Oleniacz

The chapter presents the results of analyses concerning the impact of using alternative fuels in one of the Polish cement plants on the volume of continuously measured emissions into the air for the following substances: carbon dioxide (CO2), carbon monoxide (CO), nitric oxides (NOx), sulphur dioxide (SO2), hydrogen chloride (HCl), gaseous and volatile organic compounds expressed as total organic carbon (TOC), and total dust. The analyses covered a 15-month period of the operation of a dry cement kiln, approximately 100m-long, equipped with four-stage cyclone exchangers and a calciner, constituting an additional chamber for waste co-combustion. The results obtained confirmed the ...


Mapping And Estimation Of Chemical Concentrations In Surface Soils Using Landsat Tm Satellite Imagery, Maruthi Sridhar Balaji Bhaskar 2009 Texas Southern University

Mapping And Estimation Of Chemical Concentrations In Surface Soils Using Landsat Tm Satellite Imagery, Maruthi Sridhar Balaji Bhaskar

Maruthi Sridhar Balaji Bhaskar

No abstract provided.


Comparison Of Aerosol Optical Thickness With In Situ Visibility Data Over Cyprus, A. Retalis, D. Hadjimitsis, S. Michaelides, F. Tymvios, N. Chrysoulakis, C. Clayton 2009 Selected Works

Comparison Of Aerosol Optical Thickness With In Situ Visibility Data Over Cyprus, A. Retalis, D. Hadjimitsis, S. Michaelides, F. Tymvios, N. Chrysoulakis, C. Clayton

Adrianos Retalis

The monitoring of aerosol concentrations comprises a high environmental priority, particularly in urban areas. Remote sensing of atmospheric aerosol optical thickness (AOT) could be used to assess particulate matter levels at the ground. However, such measurements often need further validation. In this study, aerosol data retrieved from satellite and sun-photometer, on the one hand, and visibility data at various locations in Cyprus, on the other hand, for the period from January to June 2009 are contrasted. The results obtained by the direct comparison between MODIS and handheld sun-photometer AOT data exhibited a significant correlation (r=0.83); these results are ...


Shoulder Surfing Resistance Using Penup Event And Neighbouring Connectivity Manipulation, Miss Laiha Mat Kiah 2009 University of Malaya

Shoulder Surfing Resistance Using Penup Event And Neighbouring Connectivity Manipulation, Miss Laiha Mat Kiah

Miss Laiha Mat Kiah

Picture-based password has been proposed as an alternative authentication method to replace text-based password. Ensuring the security of picture-based password is not a simple task as picture-based objects are a lot easier to access and remember and can thus be easily guessed. In particular, shoulder surfing attack still remains as the main security threat encountered by many picture-based password authentication schemes, especially in drawmetric authentication scheme. In this paper, a novel shoulder surfing resistance mechanism has been proposed and evaluated. The proposed mechanism utilises penup event and neighbouring connectivity manipulation into a revised Background Pass-Go scheme. From the evaluation result ...


Probabilistic Peak Calling And Controlling False Discovery Rate In Transcription Factor Binding Site Mapping From Chip-Seq, SHUO JIAO, Cheryl Bailey, Shunpu Zhang, Istvan Ladunga 2009 Fred Hutchinson Cancer Research Center

Probabilistic Peak Calling And Controlling False Discovery Rate In Transcription Factor Binding Site Mapping From Chip-Seq, Shuo Jiao, Cheryl Bailey, Shunpu Zhang, Istvan Ladunga

Shuo Jiao

No abstract provided.


Urban Aerosol Mapping Over Athens Using The Differential Textural Analysis (Dta) Algorithm On Meris-Envisat Data, A. Retalis, N. Sifakis 2009 Selected Works

Urban Aerosol Mapping Over Athens Using The Differential Textural Analysis (Dta) Algorithm On Meris-Envisat Data, A. Retalis, N. Sifakis

Adrianos Retalis

Low and moderate spatial resolution satellite sensors (such as TOMS, AVHRR, SeaWiFS) have already shown their capability in tracking aerosols at a global scale. Sensors with moderate to high spatial resolution (such as MODIS and MERIS) seem also to be appropriate for aerosol retrieval at a regional scale. We investigated in this study the potential of MERIS-ENVISAT data to resolve the horizontal spatial distribution of aerosols over urban areas, such as the Athens metropolitan area, by using the differential textural analysis (DTA) code. The code was applied to a set of geo-corrected images to retrieve and map aerosol optical thickness ...


Meta-Analysis For Surrogacy: Accelerated Failure Time Models And Semicompeting Risks Modelling, Debashis Ghosh, Jeremy Taylor, Daniel Sargent 2009 Penn State University

Meta-Analysis For Surrogacy: Accelerated Failure Time Models And Semicompeting Risks Modelling, Debashis Ghosh, Jeremy Taylor, Daniel Sargent

Debashis Ghosh

There has been great recent interest in the medical and statistical literature in the assessment and validation of surrogate endpoints as proxies for clinical endpoints in medical studies. More recently, authors have focused on using meta-analytical methods for quanti #12;cation of surrogacy. In this article, we extend existing procedures for analysis based on the accelerated failure time model to this setting. An advantage of this approach relative to proportional hazards model is that it allows for analysis in the semi-competing risks setting, where we constrain the surrogate endpoint to occur before the true endpoint. A novel principal components procedure ...


Viscoelastic Properties Of Anionic Brominated Surfactants, M Misran 2009 University Malaya

Viscoelastic Properties Of Anionic Brominated Surfactants, M Misran

Misni Misran

The scarcity of land based oil reserves has necessitated the exploration of off shore oil. This exploration is often carried out in pristine waters and the use of green chemicals is essential to reduce environmental degradation. In the recovery of oil and gas from rocky formations, well bore fluids such as packer fluids, fracturing fluids, conformance and permeability control fluids are extensively employed. Potassium oleate as viscoelastic surfactants gives a low partition coefficient when in contact with hydrocarbon. Bromination of the oleate chain has been shown in this work to increase the partition coefficient and still maintaining its viscoelasticity. The ...


Coke Formation Reduction In The Steam Cracking Of Naphtha On Industrial Alloy Steels Using Sulfur-Based Inhibitors, Darioush Salari, Aligholi Niaei, Mohammad Reza Shoja, Reza Nabavi 2009 University of Tabriz

Coke Formation Reduction In The Steam Cracking Of Naphtha On Industrial Alloy Steels Using Sulfur-Based Inhibitors, Darioush Salari, Aligholi Niaei, Mohammad Reza Shoja, Reza Nabavi

Seyed Reza nabavi

Coke formation reduction during naphtha pyrolysis was investigated using dimethyl disulfide (DMDS) and carbon disulfide (CS2) as inhibitors with different feed stocks. Different industrial nickel alloy steels such as stainless steel 304 and 316 (SS304, SS316), HP-modified (HP-mod) and HP-micro (HP-mic) were used as coupons in a quartz cylindrical reactor for coke formation studies. Coke formation significantly reduced in the presence of the additives or using feeds with more sulfur compounds. It was revealed that HP-mic alloy has the least coke deposition rate between other alloys. Scanning electron microscope (SEM) and energy dispersive X-ray analyzer (EDAX) were used for ...


Teaching Non-Mathematics Majors Using Group Topic Books, Caroline Lubert 2009 James Madison University

Teaching Non-Mathematics Majors Using Group Topic Books, Caroline Lubert

Caroline P Lubert

No abstract provided.


Effects Of Anthropogenic Influences On The Trophic State, Land Uses And Aquatic Vegetation In A Shallow Mediterranean Lake: Implications For Restoration, E. Papastergiadou, I. Kagalou, K. Stefanidis, A. Retalis, I. Leonardos 2009 Selected Works

Effects Of Anthropogenic Influences On The Trophic State, Land Uses And Aquatic Vegetation In A Shallow Mediterranean Lake: Implications For Restoration, E. Papastergiadou, I. Kagalou, K. Stefanidis, A. Retalis, I. Leonardos

Adrianos Retalis

Lake Pamvotis, NW Greece is a shallow Mediterranean eutrophic lake that has changed drastically over the past 50 years. Strong effects, resulted mainly from anthropogenic causes, in the hydrological regime are shown for this area using long term hydrological data and a GIS system for extracting land cover/use changes. A set of aerial imagery acquired in 1945 through 2002 were used to monitor and assess the spatial and temporal changes in land cover/use, focused mainly on the lake’s surface area and its surrounding ecosystem (Natura 2000 area). The significance of the changes in land cover/use distribution ...


Chirality Influence On The Aggregation Of The Methyl Mandelate, ALBRECHT, BORBA, LE BARBUS-DEBUS, DITTRICH, FAUSTO, GRIMME, MAHJOUB, NEDIC, SCHMITT, SCHARDER, SUHM, ZEHNACKER, ZISCHANG 2009 Selected Works

Chirality Influence On The Aggregation Of The Methyl Mandelate, Albrecht, Borba, Le Barbus-Debus, Dittrich, Fausto, Grimme, Mahjoub, Nedic, Schmitt, Scharder, Suhm, Zehnacker, Zischang

Dr. Ahmed MAHJOUB

No abstract provided.


The Inhibitive Effect Of Four Tetrazole Derivatives Towards 70cu30zn Corrosion In 0.1m Hno3, M. Mihit, L. Bazzi, S. Issami, B. Hammouti, R. Salghi, E. Ait Addi 2009 Ibn-Zohr University

The Inhibitive Effect Of Four Tetrazole Derivatives Towards 70cu30zn Corrosion In 0.1m Hno3, M. Mihit, L. Bazzi, S. Issami, B. Hammouti, R. Salghi, E. Ait Addi

Mihit Mohammed Ph.D

No abstract provided.


Environmental Justice And Sustainability In The Former Soviet Union, Peter Little 2009 Oregon State University

Environmental Justice And Sustainability In The Former Soviet Union, Peter Little

Peter C. Little

No abstract provided.


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