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Call For Abstracts - Resrb 2019, July 8-9, Wrocław, Poland, Wojciech M. Budzianowski Dec 2018

Call For Abstracts - Resrb 2019, July 8-9, Wrocław, Poland, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Comparing Experts And Novices In Solving Electrical Circuit Problems With The Help Of Eye-Tracking, David Rosengrant, Colin Thomson, Taha Mzoughi Jul 2017

Comparing Experts And Novices In Solving Electrical Circuit Problems With The Help Of Eye-Tracking, David Rosengrant, Colin Thomson, Taha Mzoughi

David Rosengrant

In order to help introductory physics students understand and learn to solve problems with circuits, we must first understand how they differ from experts. This preliminary study focuses on problem-solving dealing with electrical circuits. We investigate difficulties novices have with circuits and compare their work with those of experts. We incorporate the use of an eye-tracker to investigate any possible differences or similarities on how experts and novices solve electrical circuit problems. Our results show similarities in gaze patterns among all subjects on the components of the circuit. We further found that experts would look back at the circuit while …


Highly Directional Receiver And Source Antennas Using Photonic Band Gap Crystals, Rana Biswas, Gary L. Tuttle, Ekmel Ozbay, Burak Temelkuran, Mihail Sigalas, Kai-Ming Ho Jun 2017

Highly Directional Receiver And Source Antennas Using Photonic Band Gap Crystals, Rana Biswas, Gary L. Tuttle, Ekmel Ozbay, Burak Temelkuran, Mihail Sigalas, Kai-Ming Ho

Gary Tuttle

A directional antenna made with photonic band gap structures has been presented. The directional antenna is formed with two photonic band gap structures oriented back to back and separated from each other by a distance to form a resonant cavity between the photonic band gap structures. An antenna element is placed in the resonant cavity. The resonant frequency of the cavity is tuned by adjusting the distance between the photonic band gap structures. The resonant cavity can be asymmetrical or symmetrical.


Ferromagnetism Of Magnetically Doped Topological Insulators In Crxbi2− Xte3 Thin Films, Yan Ni, Z. Zhang, Ikenna C. Nlebedim, M. Ravi Hadimani, Gary L. Tuttle, David C. Jiles Jun 2017

Ferromagnetism Of Magnetically Doped Topological Insulators In Crxbi2− Xte3 Thin Films, Yan Ni, Z. Zhang, Ikenna C. Nlebedim, M. Ravi Hadimani, Gary L. Tuttle, David C. Jiles

Gary Tuttle

We investigated the effect of magnetic doping on magnetic and transport properties of Bi2Te3thin films. CrxBi2−xTe3 thin films with x = 0.03, 0.14, and 0.29 were grown epitaxially on mica substrate with low surface roughness (∼0.4 nm). It is found that Cr is an electron acceptor in Bi2Te3 and increases the magnetization of CrxBi2−xTe3. When x = 0.14 and 0.29,ferromagnetism appears in CrxBi2−xTe3 thin films, where anomalous Hall effect and weak localization of magnetoconductance were observed. The Curie temperature, coercivity, and remnant Hall resistance of thin films increase with increasing Cr concentration. The Arrott-Noakes plot demonstrates that the critical mechanism …


A Period Examination Through Contemporary Energy Analysis Of Kevin Roche’S Fine Arts Center At University Of Massachusetts-Amherst, L Carl Fiocchi Jr May 2017

A Period Examination Through Contemporary Energy Analysis Of Kevin Roche’S Fine Arts Center At University Of Massachusetts-Amherst, L Carl Fiocchi Jr

L. Carl Fiocchi

Studies of buildings belonging to a subset of Modernist architecture, Brutalism, have included discussions pertaining to social and architectural history, critical reception, tectonic form and geometry inspirations, material property selections, period technology limitations, and migration of public perceptions. Evaluations of Brutalist buildings’ energy related performances have been restricted to anecdotal observations with particular focus on the building type’s poor thermal performance, a result of the preferred construction method, i.e. monolithic reinforced concrete used as structure, interior finish and exterior finish. A valid criticism, but one that served to dismiss discussion that the possibility of other positive design strategies limiting energy …


Targeting Residential Energy Reduction For City Utilities Using Historical Electrical Utility Data And Readily Available Building Data, Kevin P. Hallinan, J. Kelly Kissock, Robert J. Brecha, Austin Mitchell Sep 2016

Targeting Residential Energy Reduction For City Utilities Using Historical Electrical Utility Data And Readily Available Building Data, Kevin P. Hallinan, J. Kelly Kissock, Robert J. Brecha, Austin Mitchell

J. Kissock

Energy use data for the eight-year period 2003–2010 was analyzed for over 1200 single family residences in Village of Yellow Springs, Ohio. Electricity, natural gas, residential building, and weather databases are merged to permit determination of the energy intensity of each home in the village. The energy use intensity for each home is disaggregated into weather independent and weather dependent electric and natural gas use. This use is compared to typical baseline, cooling, and heating energy use for the region. From this comparison, priority homes are identified for energy reduction investment. Collective potential low cost energy reduction is estimated for …


Prioritizing Investment In Residential Energy Efficiency And Renewable Energy: A Case Study For The U.S. Midwest, Robert J. Brecha, Austin Mitchell, Kevin P. Hallinan, J. Kelly Kissock Sep 2016

Prioritizing Investment In Residential Energy Efficiency And Renewable Energy: A Case Study For The U.S. Midwest, Robert J. Brecha, Austin Mitchell, Kevin P. Hallinan, J. Kelly Kissock

J. Kissock

Residential building energy use is an important contributor to greenhouse gas emissions and in the United States represents about 20% of total energy consumption. A number of previous macro-scale studies of residential energy consumption and energy-efficiency improvements are mainly concerned with national or international aggregate potential savings. In this paper we look into the details of how a collection of specific homes in one region might reduce energy consumption and carbon emissions, with particular attention given to some practical limits to what can be achieved by upgrading the existing residential building stock. Using a simple model of residential, single-family home …


Targeting Residential Energy Reduction For City Utilities Using Historical Electrical Utility Data And Readily Available Building Data, Kevin P. Hallinan, J. Kelly Kissock, Robert J. Brecha, Austin Mitchell Jun 2016

Targeting Residential Energy Reduction For City Utilities Using Historical Electrical Utility Data And Readily Available Building Data, Kevin P. Hallinan, J. Kelly Kissock, Robert J. Brecha, Austin Mitchell

Kevin Hallinan

Energy use data for the eight-year period 2003–2010 was analyzed for over 1200 single family residences in Village of Yellow Springs, Ohio. Electricity, natural gas, residential building, and weather databases are merged to permit determination of the energy intensity of each home in the village. The energy use intensity for each home is disaggregated into weather independent and weather dependent electric and natural gas use. This use is compared to typical baseline, cooling, and heating energy use for the region. From this comparison, priority homes are identified for energy reduction investment. Collective potential low cost energy reduction is estimated for …


Prioritizing Investment In Residential Energy Efficiency And Renewable Energy: A Case Study For The U.S. Midwest, Robert J. Brecha, Austin Mitchell, Kevin P. Hallinan, J. Kelly Kissock Jun 2016

Prioritizing Investment In Residential Energy Efficiency And Renewable Energy: A Case Study For The U.S. Midwest, Robert J. Brecha, Austin Mitchell, Kevin P. Hallinan, J. Kelly Kissock

Kevin Hallinan

Residential building energy use is an important contributor to greenhouse gas emissions and in the United States represents about 20% of total energy consumption. A number of previous macro-scale studies of residential energy consumption and energy-efficiency improvements are mainly concerned with national or international aggregate potential savings. In this paper we look into the details of how a collection of specific homes in one region might reduce energy consumption and carbon emissions, with particular attention given to some practical limits to what can be achieved by upgrading the existing residential building stock. Using a simple model of residential, single-family home …


Cost-Availability Curves For Hierarchical Implementation Of Residential Energy-Efficiency Measures, Roman Villoria-Siegert, Philip Brodrick, Kevin P. Hallinan, Robert J. Brecha Jun 2016

Cost-Availability Curves For Hierarchical Implementation Of Residential Energy-Efficiency Measures, Roman Villoria-Siegert, Philip Brodrick, Kevin P. Hallinan, Robert J. Brecha

Kevin Hallinan

Historical residential electricity data and natural gas consumption data were collected for, respectively, 1,200 and 178 residences in a small town in the USA. These data were merged with local building and weather databases, and energy consumption models were developed for each residence, revealing substantial variation in heating and cooling intensity. After estimating approximate physical building characteristics, energy profiles for each residence were calculated, and savings from adoption of the most cost-effective energy-efficiency measures for each residence were estimated. Effectively, we wish to leverage commonly available data sets to infer characteristics of building envelopes and equipment, without the need for …


Photoinduced Femtosecond Relaxation Of Antiferromagnetic Orders In The Iron Pnictides Revealed By Ultrafast Laser Ellipsometry, Aaron E. Patz, Tianqi Li, Sheng Ran, Sergey L. Bud'ko, Paul C. Canfield, Jigang Wang Mar 2016

Photoinduced Femtosecond Relaxation Of Antiferromagnetic Orders In The Iron Pnictides Revealed By Ultrafast Laser Ellipsometry, Aaron E. Patz, Tianqi Li, Sheng Ran, Sergey L. Bud'ko, Paul C. Canfield, Jigang Wang

Jigang Wang

We report ultrafast softening of the antiferromagnetic order, ~150fs after the electron thermalization, which follows a two-step recovery pathway to reveal a distinct interplay of magnetism and the nematic order in iron pnictides.


Variable Renewable Energy In Modeling Climate Change Mitigation Scenarios, Falko Ueckerdt, Robert J. Brecha, Gunnar Luderer, Patrick Sullivan, Eva Schmid, Nico Bauer, Diana Böttger Jun 2015

Variable Renewable Energy In Modeling Climate Change Mitigation Scenarios, Falko Ueckerdt, Robert J. Brecha, Gunnar Luderer, Patrick Sullivan, Eva Schmid, Nico Bauer, Diana Böttger

Robert J. Brecha

This paper addresses the issue of how to account for short‐term temporal variability of renewable energy sources and power demand in long‐term climate change mitigation scenarios in energy‐economic models. An approach that captures in a stylized way the major challenges to the integration of variable renewable energy sources into power systems has been developed. As a first application this approach has been introduced to REMIND‐D, a hybrid energy‐economy model of Germany. An approximation of the residual load duration curve is implemented. The approximating function endogenously changes depending on the penetration and mix of variable renewable power. The approach can thus …


Establishing Building Recommissioning Priorities And Potential Energy Savings From Utility Energy Data, Kevin P. Hallinan, Philip Brodrick, Jessica Northridge, J. Kelly Kissock, Robert J. Brecha Jun 2015

Establishing Building Recommissioning Priorities And Potential Energy Savings From Utility Energy Data, Kevin P. Hallinan, Philip Brodrick, Jessica Northridge, J. Kelly Kissock, Robert J. Brecha

Robert J. Brecha

An energy reduction program for commercial buildings is implemented for a SW Ohio natural gas utility. The aim of this study is to demonstrate that historical utility data for individual building customers, along with knowledge of pertinent building information (square footage, year built, number of floors, height of floors, wall construction type, and use type) available in county auditor databases, could be used to identify the best candidate buildings for recommissioning in terms of energy savings and simple payback. A study is completed for all natural gas customers of a utility in Montgomery and Clinton counties in Ohio. A total …


Cooling Atoms In An Optical Trap By Selective Parametric Excitation, Nicola Poli, Robert J. Brecha, Giacomo Roati, Giovanni Modugno Jun 2015

Cooling Atoms In An Optical Trap By Selective Parametric Excitation, Nicola Poli, Robert J. Brecha, Giacomo Roati, Giovanni Modugno

Robert J. Brecha

We demonstrate the possibility of energy-selective removal of cold atoms from a tight optical trap by means of parametric excitation of the trap vibrational modes. Taking advantage of the anharmonicity of the trap potential, we either selectively remove the most energetic trapped atoms or excite those at the bottom of the trap by tuning the parametric modulation frequency. This process, which had been previously identified as a possible source of heating, also appears to be a robust way for forcing evaporative cooling in anharmonic traps.


Rose: Roadmaps Towards Sustainable Energy Futures And Climate Protection: A Synthesis Of Results From The Rose Project, Elmar Kriegler, Ioanna Mouratiadou, Gunnar Luderer, Nico Bauer, Katherine Calvin, Enrica Decian, Robert J. Brecha, Wenying Chen, Aleh Cherp, Jae Edmonds, Kejun Jiang, Shonali Pachauri, Fabio Sferra, Massimo Tavoni, Ottmar Edenhofer Jun 2015

Rose: Roadmaps Towards Sustainable Energy Futures And Climate Protection: A Synthesis Of Results From The Rose Project, Elmar Kriegler, Ioanna Mouratiadou, Gunnar Luderer, Nico Bauer, Katherine Calvin, Enrica Decian, Robert J. Brecha, Wenying Chen, Aleh Cherp, Jae Edmonds, Kejun Jiang, Shonali Pachauri, Fabio Sferra, Massimo Tavoni, Ottmar Edenhofer

Robert J. Brecha

EXECUTIVE SUMMARY Exploring energy demand and supply uncertainty: An exploration of uncertainty on drivers of energy demand and supply is indispensable for better understanding the prospects of long-tern climate stabilization. The RoSE study is the first of its kind to systematically explore the impact of economic growth, population and fossil fuel scarcity, in scenarios with and without climate policy, using a model ensemble. A feature of RoSE is the participation of five established integrated assessment modelling teams from three important regions in international climate policy negotiations: the EU, the USA and China. Economic growth: Neither slow nor rapid economic growth …


Two-Level Atom In An Optical Parametric Oscillator: Spectra Of Transmitted And Fluorescent Fields In The Weak Driving Field Limit, James P. Clemens, Perry R. Rice, Pranaw Kumar Rungta, Robert J. Brecha Jun 2015

Two-Level Atom In An Optical Parametric Oscillator: Spectra Of Transmitted And Fluorescent Fields In The Weak Driving Field Limit, James P. Clemens, Perry R. Rice, Pranaw Kumar Rungta, Robert J. Brecha

Robert J. Brecha

We consider the interaction of a two-level atom inside an optical parametric oscillator. In the weak-driving-field limit, we essentially have an atom-cavity system driven by the occasional pair of correlated photons, or weakly squeezed light. We find that we may have holes, or dips, in the spectrum of the fluorescent and transmitted light. This occurs even in the strong-coupling limit when we find holes in the vacuum-Rabi doublet. Also, spectra with a subnatural linewidth may occur. These effects disappear for larger driving fields, unlike the spectral narrowing obtained in resonance fluorescence in a squeezed vacuum; here it is important that …


Renewable Energy In The Context Of Sustainable Development, Jayant Sathaye, Oswaldo Lucon, Atiq Rahman, John Christensen, Fatima Denton, Junichi Fujino, Garvin Heath, Monirul Mirza, Hugh Rudnick, August Schlaepfer, Andrey Shmakin, Gerhard Angerer, Christian Bauer, Morgan Bazilian, Robert J. Brecha, Peter Burgherr, Leon Clarke, Felix Creutzig, James Edmonds, Christian Hagelüken, Gerrit Hansen, Nathan Hultman, Michael Jakob, Susanne Kadner, Manfred Lenzen, Jordan Macknick, Eric Masanet, Yu Nagai, Anne Olhoff, Karen Olsen, Michael Pahle, Ari Rabl, Richard Richels, Joyashree Roy, Tormod Schei, Christoph Von Stechow, Jan Christoph Steckel, Ethan Warner, Tom Wilbanks, Yimin Zhang Jun 2015

Renewable Energy In The Context Of Sustainable Development, Jayant Sathaye, Oswaldo Lucon, Atiq Rahman, John Christensen, Fatima Denton, Junichi Fujino, Garvin Heath, Monirul Mirza, Hugh Rudnick, August Schlaepfer, Andrey Shmakin, Gerhard Angerer, Christian Bauer, Morgan Bazilian, Robert J. Brecha, Peter Burgherr, Leon Clarke, Felix Creutzig, James Edmonds, Christian Hagelüken, Gerrit Hansen, Nathan Hultman, Michael Jakob, Susanne Kadner, Manfred Lenzen, Jordan Macknick, Eric Masanet, Yu Nagai, Anne Olhoff, Karen Olsen, Michael Pahle, Ari Rabl, Richard Richels, Joyashree Roy, Tormod Schei, Christoph Von Stechow, Jan Christoph Steckel, Ethan Warner, Tom Wilbanks, Yimin Zhang

Robert J. Brecha

Historically, economic development has been strongly correlated with increasing energy use and growth of greenhouse gas (GHG) emissions. Renewable energy (RE) can help decouple that correlation, contributing to sustainable development (SD). In addition, RE offers the opportunity to improve access to modern energy services for the poorest members of society, which is crucial for the achievement of any single of the eight Millennium Development Goals. Theoretical concepts of SD can provide useful frameworks to assess the interactions between SD and RE. SD addresses concerns about relationships between human society and nature. Traditionally, SD has been framed in the three-pillar model—Economy, …


Ten Reasons To Take Peak Oil Seriously, Robert Brecha Jun 2015

Ten Reasons To Take Peak Oil Seriously, Robert Brecha

Robert J. Brecha

Forty years ago, the results of modeling, as presented in The Limits to Growth, reinvigorated a discussion about exponentially growing consumption of natural resources, ranging from metals to fossil fuels to atmospheric capacity, and how such consumption could not continue far into the future. Fifteen years earlier, M. King Hubbert had made the projection that petroleum production in the continental United States would likely reach a maximum around 1970, followed by a world production maximum a few decades later. The debate about “peak oil," as it has come to be called, is accompanied by some of the same vociferous denials, …


Investigation Of Cdznte Crystal Defects Using Scanning Probe Microscopy, Goutam Koley, J. Liu, K. C. Mandal Apr 2015

Investigation Of Cdznte Crystal Defects Using Scanning Probe Microscopy, Goutam Koley, J. Liu, K. C. Mandal

Krishna C. Mandal

No abstract provided.


Erratum: “Terahertz Studies Of The Dielectric Response And Second-Order Phonons In A Gase Crystal” [Appl. Phys. Lett.87, 182104 (2005)], B. L. Yu, F. Zeng, V. Kartazayev, R. R. Alfano, K. C. Mandal Apr 2015

Erratum: “Terahertz Studies Of The Dielectric Response And Second-Order Phonons In A Gase Crystal” [Appl. Phys. Lett.87, 182104 (2005)], B. L. Yu, F. Zeng, V. Kartazayev, R. R. Alfano, K. C. Mandal

Krishna C. Mandal

No abstract provided.


Investigation Of Cdznte Crystal Defects Using Scanning Probe Microscopy, Goutam Koley, J. Liu, K. C. Mandal Apr 2015

Investigation Of Cdznte Crystal Defects Using Scanning Probe Microscopy, Goutam Koley, J. Liu, K. C. Mandal

Krishna C. Mandal

No abstract provided.


Tb3+-Doped K Pb2Br5: Low-Energy Phonon Mid-Infrared Laser Crystal, U. N. Roy, R. H. Hawrami, Y. Cui, S. Morgan, A. Burger, K. C. Mandal, C. C. Noblitt, S. A. Speakman, K. Rademaker, S. A. Payne Apr 2015

Tb3+-Doped K Pb2Br5: Low-Energy Phonon Mid-Infrared Laser Crystal, U. N. Roy, R. H. Hawrami, Y. Cui, S. Morgan, A. Burger, K. C. Mandal, C. C. Noblitt, S. A. Speakman, K. Rademaker, S. A. Payne

Krishna C. Mandal

No abstract provided.


Doping Dependence Of Electronic And Mechanical Properties Of Gase1−XTeX And Ga1−XInXSe From First Principles, Zs. Rak, S. D. Mahanti, K. C. Mandal, N. C. Fernelius Apr 2015

Doping Dependence Of Electronic And Mechanical Properties Of Gase1−XTeX And Ga1−XInXSe From First Principles, Zs. Rak, S. D. Mahanti, K. C. Mandal, N. C. Fernelius

Krishna C. Mandal

No abstract provided.


Investigation Of Cdznte Crystal Defects Using Scanning Probe Microscopy, Goutam Koley, J. Liu, K. C. Mandal Apr 2015

Investigation Of Cdznte Crystal Defects Using Scanning Probe Microscopy, Goutam Koley, J. Liu, K. C. Mandal

Krishna C. Mandal

No abstract provided.


Properties Of Exchange Coupled All-Garnet Magneto-Optic Thin Film Multilayer Structures, Mohammad Nur-E-Alam, Mikhail Vasiliev, Viacheslav A. Kotov, Dmitry Balabanov, Ilya Akimov, Kamal Alameh Apr 2015

Properties Of Exchange Coupled All-Garnet Magneto-Optic Thin Film Multilayer Structures, Mohammad Nur-E-Alam, Mikhail Vasiliev, Viacheslav A. Kotov, Dmitry Balabanov, Ilya Akimov, Kamal Alameh

Mikhail Vasiliev

The effects of exchange coupling on magnetic switching properties of all-garnet multilayer thin film structures are investigated. All-garnet structures are fabricated by sandwiching a magneto-soft material of composition type Bi1.8Lu1.2Fe3.6Al1.4O12 or Bi3Fe5O12:Dy2O3 in between two magneto-hard garnet material layers of composition type Bi2Dy1Fe4Ga1O12 or Bi2Dy1Fe4Ga1O12:Bi2O3. The fabricated RF magnetron sputtered exchange-coupled all-garnet multilayers demonstrate a very attractive combination of magnetic properties, and are of interest for emerging applications in optical sensors and isolators, ultrafast nanophotonics and magneto-plasmonics. An unconventional type of magnetic hysteresis behavior not observed previously in magnetic garnet thin films is reported and discussed.


Applications Of High Throughput (Combinatorial) Methodologies To Electronic, Magnetic, Optical, And Energy-Related Materials, Martin L. Green, Ichiro Takeuchi, Jason R. Hattrick-Simpers Mar 2015

Applications Of High Throughput (Combinatorial) Methodologies To Electronic, Magnetic, Optical, And Energy-Related Materials, Martin L. Green, Ichiro Takeuchi, Jason R. Hattrick-Simpers

Jason R. Hattrick-Simpers

High throughput (combinatorial) materials science methodology is a relatively new research paradigm that offers the promise of rapid and efficient materials screening, optimization, and discovery. The paradigm started in the pharmaceutical industry but was rapidly adopted to accelerate materials research in a wide variety of areas. High throughput experiments are characterized by synthesis of a “library” sample that contains the materials variation of interest (typically composition), and rapid and localized measurement schemes that result in massive data sets. Because the data are collected at the same time on the same “library” sample, they can be highly uniform with respect to …


Combinatorial Investigation Of Magnetostriction In Fe-Fa And Fe-Ga-Al, Jason R. Hattrick-Simpers, Dwight Hunter, Corneliu M. Craciunescu, Kyu Sung Jang, Makoto Murakami, James Cullen, Manfred Wuttig, Ichiro Takeuchi, Samuel E. Lofland, Leonid Bendersky, Noble Woo, Robert Bruce Vandover, Toshiya Takahashi, Yasubumi Furuya Mar 2015

Combinatorial Investigation Of Magnetostriction In Fe-Fa And Fe-Ga-Al, Jason R. Hattrick-Simpers, Dwight Hunter, Corneliu M. Craciunescu, Kyu Sung Jang, Makoto Murakami, James Cullen, Manfred Wuttig, Ichiro Takeuchi, Samuel E. Lofland, Leonid Bendersky, Noble Woo, Robert Bruce Vandover, Toshiya Takahashi, Yasubumi Furuya

Jason R. Hattrick-Simpers

A high-throughput high-sensitivity optical technique for measuringmagnetostriction of thin-film composition-spread samples has been developed. It determines the magnetostriction by measuring the induced deflection of micromachined cantilever unimorph samples. Magnetostrictionmeasurements have been performed on as-deposited Fe–Ga and Fe–Ga–Al thin-film composition spreads. The thin-film Fe–Ga spreads display a similar compositional variation of magnetostriction as bulk. A previously undiscovered peak in magnetostriction at low Ga content was also observed and attributed to a maximum in the magnetocrystalline anisotropy. Magnetostrictive mapping of the Fe–Ga–Al ternary system reveals the possibility of substituting up to 8at.%Al in Fe70Ga30 without significant degradation of magnetostriction.


Sensitive And Ultra-Fast Species Detection Using Pulsed Cavity Ringdown Spectroscopy, Et-Touhami Es-Sebbar Mar 2015

Sensitive And Ultra-Fast Species Detection Using Pulsed Cavity Ringdown Spectroscopy, Et-Touhami Es-Sebbar

Dr. Et-touhami Es-sebbar

Pulsed cavity ringdown spectroscopy (CRDS) is used to develop a novel, ultra-fast, high-sensitivity diagnostic for measuring species concentrations in shock tube experiments. The diagnostic is demonstrated by monitoring trace concentrations of ethylene in the mid-IR region near 949.47 cm−1. Each ringdown measurement is completed in less than 1 μs and the time period between successive pulses is 10 μs. The high sensitivity diagnostic has a noise-equivalent detection limit of 1.08 x 10−5 cm−1 which enables detection of 15 ppm ethylene at fuel pyrolysis conditions (1845 K and 2 bar) and 294 ppb ethylene under ambient conditions (297 K and 1 …


Self-Assembled Composite Nano-/Micronecklaces With Sio2 Beads In Boron Strings, Hai Ni, Xiaodong Li Feb 2015

Self-Assembled Composite Nano-/Micronecklaces With Sio2 Beads In Boron Strings, Hai Ni, Xiaodong Li

Xiaodong Li

Nano-/micronecklaces with SiO2 beads in boron strings were synthesized by simply sublimating the desired powders in a sealed quartz tube at high temperature. The boron strings have a rectangular cross section with width varying from 80to1000nm while the SiO2 beads bear either spindle or spherical shape with a size ranging from 100nmto5μm. The spacing between the SiO2 beads is uniform in each boron string. Both the boron strings and the SiO2 beads are amorphous and free of defects. The supersaturated vapors of silicon and oxygen induced the SiO2 bead formation.


Zespół Energii Odnawialnej I Zrównoważonego Rozwoju (Eozr), Wojciech M. Budzianowski Dec 2014

Zespół Energii Odnawialnej I Zrównoważonego Rozwoju (Eozr), Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.