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Hydrogen Bonding: A low-energy attractive force between hydrogen and another element. It plays a major role in determining the properties of water, proteins, and other compounds.

Magnetic and Thermal-sensitive Poly(N-isopropylacrylamide)-based Microgels for Magnetically Triggered Controlled Release

1Institute of Polymer Science and Engineering, National Taiwan University, 2Department of Materials Engineering, Ming Chi University of Technology, 3Department of Metallurgy and Materials Engineering, Bandung Institute of Technology and Science, 4Department of Chemical Engineering, National Taiwan University, 5Department of Materials Science and Engineering, National Taiwan University

JoVE 55648


 Bioengineering

Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities

1Department of Physics, University of California at Berkeley, 2Department of Chemistry, University of California at Berkeley, 3Department of Chemical and Biomolecular Engineering, University of California at Berkeley, 4National Institute for Materials Science (Japan), 5Materials Sciences Division, Lawrence Berkeley National Laboratory, 6Kavli Energy NanoSciences Institute, University of California at Berkeley and Lawrence Berkeley National Laboratory

JoVE 52711


 Engineering

Quadruply Metal-Metal Bonded Paddlewheels

JoVE 10441

Source: Corey Burns, Tamara M. Powers, Department of Chemistry, Texas A&M University

Paddlewheel complexes are a class of compounds comprised of two metal ions (1st, 2nd, or 3rd row transition metals) held in proximity by four bridging ligands (most commonly formamidinates or carboxylates) (Figure 1). Varying the identity of the metal ion and the bridging ligand provides access to large families of paddlewheel complexes. The structure of paddlewheel complexes allows for metal-metal bonding, which plays a vital role in the structure and reactivity of these complexes. Due to the diversity of electronic structures that are available to paddlewheel complexes - and the corresponding differences in M-M bonding displayed by these structures - paddlewheel complexes have found application in diverse areas, such as in homogeneous catalysis and as building blocks for metal-organic frameworks (MOFs). Understanding the electronic structure of the M-M bonds in paddlewheel complexes is critical to understanding their structures and thus to application of these complexes in coordination chemistry and catalysis. Figure 1. General structure of paddlewheel complexes, wh


 Inorganic Chemistry

A Convenient Method for Extraction and Analysis with High-Pressure Liquid Chromatography of Catecholamine Neurotransmitters and Their Metabolites

1School of Public Health of Southeast University, Laboratory of Environment and Biosafety Research Institute of Southeast University in Suzhou, 2Key Laboratory of Child Development and Learning Science (Ministry of Education), School of Biological Science & Medical Engineering, Southeast University, 3School of Public Health, Tianjin Medical University, 4British Columbia Academy, Nanjing Foreign Language School

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JoVE 56445


 JoVE In-Press

Ideal Gas Law

JoVE 5537

Source: Laboratory of Dr. Andreas Züttel - Swiss Federal Laboratories for Materials Science and Technology

The ideal gas law describes the behavior of most common gases at near-ambient conditions and the tendency of all chemical matter in the dilute limit. It is a fundamental relationship between three measurable macroscopic system variables (pressure, temperature, and volume) and the number of molecules of gas in the system, and is therefore an essential link between the microscopic and the macroscopic universes. The history of the ideal gas law dates to the middle of the 17th century when the relationship between the pressure and volume of air was found to be inversely proportional, an expression confirmed by Robert Boyle and which we now refer to as Boyle’s law (Equation 1). P V-1 (Equation 1) Unpublished work by Jacques Charles in the 1780s, which was extended to numerous gases and vapors by Joseph Louis Gay-Lussac and reported in 1802, established the directly proportional relationship between the absolute temperature and volume of a gas. This relationship is called Charles's law (Equ


 General Chemistry

Fabrication of a Functionalized Magnetic Bacterial Nanocellulose with Iron Oxide Nanoparticles

1Department of Bioengineering, University of Illinois at Urbana-Champaign, 2Department of Nuclear, Plasma and Radiological Engineering, University of Illinois at Urbana-Champaign, 3Micro and Nanotechnology Laboratory, University of Illinois at Urbana-Champaign, 4Program of Study and Control of Tropical Diseases (PECET), University of Antioquia, 5Sealy Center for Vaccine Development, University of Texas Medical Branch, 6WHO Collaborating Center for Vaccine Research, Evaluation and Training on Emerging Infectious Diseases, University of Texas Medical Branch, 7Beckman Institute, University of Illinois at Urbana-Champaign

JoVE 52951


 Bioengineering

Characterizing Electron Transport through Living Biofilms

1Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, 2George Mason University, 3Chemistry Division, Naval Research Laboratory, 4Departments of Physics, Biological Sciences, and Chemistry, University of Southern California, 5Department of Chemical Engineering and Materials Science, Michigan State University

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JoVE 54671


 JoVE In-Press

Engineering 'Golden' Fluorescence by Selective Pressure Incorporation of Non-Canonical Amino Acids and Protein Analysis by Mass Spectrometry and Fluorescence

1Institute of Chemistry L 1, Department of Biocatalysis, Technical University of Berlin, 2Institute of Chemistry PC 14, Department of Bioenergetics, Technical University of Berlin, 3Institute of Chemistry TC 7, Department of Physical Chemistry/Molecular Material Sciences, Technical University of Berlin

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JoVE 57017


 JoVE In-Press

Lewis Acid-Base Interaction in Ph3P-BH3

JoVE 10316

Source: Tamara M. Powers, Department of Chemistry, Texas A&M University 

One of the goals of chemistry is to use models that account for trends and provide insights into the properties of reactants that contribute to reactivity. Substances have been classified as acids and bases since the time of the ancient Greeks, but the definition of acids and bases has been modified and expanded over the years.1 The ancient Greeks would characterize substances by taste, and defined acids as those that were sour-tasting, such as lemon juice and vinegar. The term "acid" is derived from the Latin term for "sour-tasting." Bases were characterized by their ability to counteract or neutralize acids. The first bases characterized were those of ashes from a fire, which were mixed with fats to make soap. In fact, the term "alkaline" is derived from the Arabic word for "roasting." Indeed, it has been known since ancient times that acids and bases can be combined to give a salt and water. The first widely-used description of an acid is that of the Swedish chemist, Svante Arrhenius, who in 1894 defined acids as substances which dissociate in water to give hydronium ions, and bases as substances which dissociate in water to give


 Inorganic Chemistry

Structure Of Ferrocene

JoVE 10347

Source: Tamara M. Powers, Department of Chemistry, Texas A&M University 

In 1951, Kealy and Pauson reported to Nature the synthesis of a new organometallic compound, ferrocene.1 In their original report, Pauson suggested a structure for ferrocene in which the iron is singly bonded (sigma bonds) to one carbon atom of each cyclopentadiene ligand (Figure 1, Structure I).1,2,3 This initial report led to wide-spread interest in the structure of ferrocene, and many leading scientists participated in the structure elucidation of this interesting new molecule. Wilkinson and Woodward were quick to suggest an alternative formulization where the iron is "sandwiched" between two cyclopentadiene ligands, with equal binding to all 10 carbon atoms (Figure 1, Structure II).4 Here, we will synthesize ferrocene and decide, based on experimental data (IR and 1H NMR), which of these structures is observed. In addition, we will study the electrochemistry of ferrocene by collecting a cyclic voltammogram. In the course of this experiment, we introduce the 18-electron rule and discuss valence electron counting for transitio


 Inorganic Chemistry

Low-energy Cathodoluminescence for (Oxy)Nitride Phosphors

1Graduate School of Pure and Applied Science, University of Tsukuba, 2CNRS — Saint-Gobain, UMI 3629, Laboratory for Innovative Key Materials and Structures (LINK), 3Nano Device Characterization Group, National Institute for Materials Science (NIMS), 4Sialon Unit, National Institute for Materials Science (NIMS)

JoVE 54249


 Chemistry

Microfluidic-based Synthesis of Covalent Organic Frameworks (COFs): A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface

1Institute of Chemical and Bioengineering, Department of Chemistry and Applied Bioscience, ETH Zurich, 2Departamento de Química Inorgánica, Universidad Autónoma de Madrid, 3Departamento de Química Inorgánica, Universidad de Granada, 4Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), 5School of Chemistry, University of Nottingham, 6Condensed Matter Physics Center (IFMAC), Universidad Autónoma de Madrid, 7Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA Nanociencia)

JoVE 56020


 Chemistry

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