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Fossil Fuels: Any combustible hydrocarbon deposit formed from the remains of prehistoric organisms. Examples are petroleum, coal, and natural gas.
 Science Education: Essentials of Environmental Science

Proton Exchange Membrane Fuel Cells

JoVE Science Education

Source: Laboratories of Margaret Workman and Kimberly Frye - Depaul University

The United States consumes a large amount of energy – the current rate is around 97.5 quadrillion BTUs annually. The vast majority (90%) of this energy comes from non-renewable fuel sources. This energy is used for electricity (39%), transportation (28%), industry (22%), and residential/commercial use (11%). As the world has a limited supply of these non-renewable sources, the United States (among others) is expanding the use of renewable energy sources to meet future energy needs. One of these sources is hydrogen. Hydrogen is considered a potential renewable fuel source, because it meets many important criteria: it’s available domestically, it has few harmful pollutants, it’s energy efficient, and it’s easy to harness. While hydrogen is the most abundant element in the universe, it is only found in compound form on Earth. For example, it is combined with oxygen in water as H2O. To be useful as a fuel, it needs to be in the form of H2 gas. Therefore, if hydrogen is to be used as a fuel for cars or other electronics, H2 needs to be made first. Thusly, hydrogen is often called an “energy carrier” rather than a “fuel.”

 JoVE Bioengineering

Fast Pyrolysis of Biomass Residues in a Twin-screw Mixing Reactor

1Institute of Catalysis Research and Technology (IKFT), Karlsruhe Institute of Technology (KIT)


JoVE 54395

 JoVE Chemistry

Characterization, Quantification and Compound-specific Isotopic Analysis of Pyrogenic Carbon Using Benzene Polycarboxylic Acids (BPCA)

1Department of Geography, University of Zurich, 2Department of Earth and Ocean Sciences, University of South Carolina, 3Department of Earth Sciences, ETH Zurich, 4Laboratory of Ion Beam Physics, ETH Zurich, 5Department of Geological Sciences, Stockholm University


JoVE 53922

 Science Education: Essentials of Environmental Science

Biofuels: Producing Ethanol from Cellulosic Material

JoVE Science Education

Source: Laboratories of Margaret Workman and Kimberly Frye - Depaul University

In this experiment, cellulosic material (such as corn stalks, leaves, grasses, etc.) will be used as a feedstock for the production of ethanol. The cellulosic material is first pretreated (ground and heated), digested with enzymes, and then fermented with yeast. Ethanol production is monitored using an ethanol probe. The experiment can be extended to optimize ethanol production by varying the feedstock used, pretreatment conditions, enzyme variation, yeast variation, etc. An alternative method of monitoring the reaction is to measure the carbon dioxide produced (using a gas sensor) instead of the ethanol. As a low-tech alternative, glucose meters (found in any drug store) can be used to monitor the glucose during the process, if an ethanol probe or carbon dioxide gas sensor is not available. With an increased emphasis on ‘inquiry-based learning”, scientific probes are becoming more popular. Handheld devices like the Vernier Lab Quest used in conjunction with a variety of probes (such as those for conductivity, dissolved oxygen, voltage, and more) allow for less focus on collecting data and/or making graphs and more on analyzing the data and making predictions. Anothe

 JoVE Environment

Transcript and Metabolite Profiling for the Evaluation of Tobacco Tree and Poplar as Feedstock for the Bio-based Industry

1Max Planck Institute for Molecular Plant Physiology, 2School of Biological Sciences, Plant Molecular Science, Centre for Systems and Synthetic Biology, Royal Holloway, University of London, 3Department of Plant Systems Biology, VIB, 4Department of Plant Biotechnology and Bioinformatics, UGhent, 5Institute for Building Materials, ETH Zurich, 6Applied Wood Materials, EMPA, 7Division of Glycoscience, School of Biotechnology, AlbaNova University Center, Royal Institute of Technology (KTH), 8European Research and Project Office GmbH, 9ABBA Gaia S.L., 10Pflanzenöltechnologie, 11Capax Environmental Services, 12Green Fuels, 13Neutral Consulting Ltd, 14Plant Cell Biology Research Centre, School of Botany, University of Melbourne


JoVE 51393

 JoVE Bioengineering

Techniques for the Evolution of Robust Pentose-fermenting Yeast for Bioconversion of Lignocellulose to Ethanol

1Bioenergy Research Unit, National Center for Agricultural Utilization Research, 2Mycotoxin Prevention and Applied Microbiology Research Unit, National Center for Agricultural Utilization Research, 3Chemical Engineering and Material Science, Great Lakes Bioenergy Center, Michigan State University


JoVE 54227

 Science Education: Essentials of Environmental Science

Determination Of NOx in Automobile Exhaust Using UV-VIS Spectroscopy

JoVE Science Education

Source: Laboratories of Margaret Workman and Kimberly Frye - Depaul University

In the troposphere, ozone is naturally formed when sunlight splits nitrogen dioxide (NO2):

NO2 + sunlight → NO + O

O + O2 O3 Ozone (O3) can go on to react with nitric oxide (NO) to form nitrogen dioxide (NO2) and oxygen: NO + O3 → NO2 + O2 This results in no net gain of ozone (O3). However, with the anthropogenic production of ozone forming precursors (NO, NO2, and volatile organic compounds) through the combustion of fossil fuels, elevated levels of ozone in the troposphere have been found. Motor vehicle exhaust is a significant source of these ozone forming precursors: NO, NO2, and volatile organic compounds (VOCs). For example, mobile sources make up nearly 60% of NO + NO2 emissions. At the high temperatures found in a car’s combustion chamber, nitrogen and oxygen from the air react to form nitric oxide (NO) and nitrogen dioxide (NO2):

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 JoVE Chemistry

Towards Biomimicking Wood: Fabricated Free-standing Films of Nanocellulose, Lignin, and a Synthetic Polycation

1Institute for Critical Technology and Applied Science, Virginia Tech, 2Macromolecules and Interfaces Institute, Virginia Tech, 3Institute for Food Safety and Health, Illinois Institute of Technology- Moffett Campus, 4Wood, Cellulose, and Paper Research Department, University of Guadalajara, 5Department of Sustainable Biomaterials, Virginia Tech, 6Sustainable Nanotechnology Interdisciplinary Graduate Education Program, Virginia Tech


JoVE 51257

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 Science Education: Essentials of Earth Science

An Overview of Alkenone Biomarker Analysis for Paleothermometry

JoVE Science Education

Source: Laboratory of Jeff Salacup - University of Massachusetts Amherst

Throughout this series of videos, natural samples were extracted and purified in search of organic compounds, called biomarkers, that can relate information on climates and environments of the past. One of the samples analyzed was sediment. Sediments accumulate over geologic time in basins, depressions in the Earth into which sediment flows through the action of fluid (water or air), movement, and gravity. Two main types of basins exist, marine (oceans and seas) and lacustrine (lakes). As one might guess, very different types of life live in these settings, driven in large part by the difference in salinity between them. Over the last few decades, organic geochemists discovered a toolbox of biomarker proxies, or compounds that can be used to describe climate or environment, some of which work in marine environments and some of which work in lacustrine. We turn our attention here to the marine realm and alkenone paleothermometry using the Uk'37 sea surface temperature proxy. The most well-established and widely applied open-ocean biomarker sea surface temperature (SST) proxy is Uk'37. Uk'37 = (C37:2) / (C37:2 + C37:

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 JoVE Bioengineering

Characterization Of Multi-layered Fish Scales (Atractosteus spatula) Using Nanoindentation, X-ray CT, FTIR, and SEM

1Geotechnical and Structures Laboratory, U.S. Army Engineer Research and Development Center, 2Department of Mechanical Engineering, University of Alabama, 3Environmental Laboratory, U.S. Army Engineer Research and Development Center


JoVE 51535

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 JoVE Bioengineering

The Portable Chemical Sterilizer (PCS), D-FENS, and D-FEND ALL: Novel Chlorine Dioxide Decontamination Technologies for the Military

1United States Army-Natick Soldier RD&E Center, Warfighter Directorate, 2Department of Molecular Biology and Biophysics, University of Connecticut Health Center, 3Lawrence Livermore National Laboratory, 4Children's Hospital Oakland Research Institute


JoVE 4354

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