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Sample records for 247-majors organic chemistry

  1. Organic Chemistry Made Easy.

    ERIC Educational Resources Information Center

    Bradt, Steve

    1998-01-01

    Student-led workshops are helping undergraduate students learn from each other as they tackle organic chemistry. Each week, small groups brainstorm tough problems in sessions guided by upper-class students who have taken and passed the course. Debating and discussing chemistry problems with peers engages students with the material and boosts…

  2. Online Organic Chemistry

    ERIC Educational Resources Information Center

    Janowicz, Philip A.

    2010-01-01

    This is a comprehensive study of the many facets of an entirely online organic chemistry course. Online homework with structure-drawing capabilities was found to be more effective than written homework. Online lecture was found to be just as effective as in-person lecture, and students prefer an online lecture format with shorter Webcasts. Online…

  3. Organic Chemistry in Space

    NASA Technical Reports Server (NTRS)

    Charnley, Steven

    2009-01-01

    Astronomical observations, theoretical modeling, laboratory simulation and analysis of extraterrestrial material have enhanced our knowledge of the inventory of organic matter in the interstellar medium (ISM) and on small bodies such as comets and asteroids (Ehrenfreund & Charnley 2000). Comets, asteroids and their fragments, meteorites and interplanetary dust particles (IDPs), contributed significant amounts of extraterrestrial organic matter to the young Earth. This material degraded and reacted in a terrestrial prebiotic chemistry to form organic structures that may have served as building blocks for life on the early Earth. In this talk I will summarize our current understanding of the organic composition and chemistry of interstellar clouds. Molecules of astrobiological relevance include the building blocks of our genetic material: nucleic acids, composed of subunits such as N-heterocycles (purines and pyrimidines), sugars and amino acids. Signatures indicative of inheritance of pristine and modified interstellar material in comets and meteorites will also be discussed.

  4. The Birthday of Organic Chemistry.

    ERIC Educational Resources Information Center

    Benfey, Otto Theodor; Kaufman, George B.

    1979-01-01

    Describes how the synthesis of urea, 150 years ago, was a major factor in breaking the artificial barrier that existed between organic and inorganic chemistry, and this contributed to the rapid growth of organic chemistry. (GA)

  5. Six Pillars of Organic Chemistry

    ERIC Educational Resources Information Center

    Mullins, Joseph J.

    2008-01-01

    This article describes an approach to teaching organic chemistry, which is to have students build their knowledge of organic chemistry upon a strong foundation of the fundamental concepts of the subject. Specifically, the article focuses upon a core set of concepts that I call "the six pillars of organic chemistry": electronegativity, polar…

  6. Organic chemistry on Titan

    NASA Technical Reports Server (NTRS)

    Chang, S.; Scattergood, T.; Aronowitz, S.; Flores, J.

    1979-01-01

    Features taken from various models of Titan's atmosphere are combined in a working composite model that provides environmental constraints within which different pathways for organic chemical synthesis are determined. Experimental results and theoretical modeling suggest that the organic chemistry of the satellite is dominated by two processes: photochemistry and energetic particle bombardment. Photochemical reactions of CH4 in the upper atmosphere can account for the presence of C2 hydrocarbons. Reactions initiated at various levels of the atmosphere by cosmic rays, Saturn 'wind', and solar wind particle bombardment of a CH4-N2 atmospheric mixture can account for the UV-visible absorbing stratospheric haze, the reddish appearance of the satellite, and some of the C2 hydrocarbons. In the lower atmosphere photochemical processes will be important if surface temperatures are sufficiently high for gaseous NH3 to exist. It is concluded that the surface of Titan may contain ancient or recent organic matter (or both) produced in the atmosphere.

  7. Organic chemistry on Titan

    NASA Technical Reports Server (NTRS)

    Chang, S.; Scattergood, T.; Aronowitz, S.; Flores, J.

    1978-01-01

    Observations of nonequilibrium phenomena on the Saturn satellite Titan indicate the occurrence of organic chemical evolution. Greenhouse and thermal inversion models of Titan's atmosphere provide environmental constraints within which various pathways for organic chemical synthesis are assessed. Experimental results and theoretical modeling studies suggest that the organic chemistry of the satellite may be dominated by two atmospheric processes: energetic-particle bombardment and photochemistry. Reactions initiated in various levels of the atmosphere by cosmic ray, Saturn wind, and solar wind particle bombardment of a CH4 - N2 atmospheric mixture can account for the C2-hydrocarbons, the UV-visible-absorbing stratospheric haze, and the reddish color of the satellite. Photochemical reactions of CH4 can also account for the presence of C2-hydrocarbons. In the lower Titan atmosphere, photochemical processes will be important if surface temperatures are sufficiently high for gaseous NH3 to exist. Hot H-atom reactions initiated by photo-dissociation of NH3 can couple the chemical reactions of NH3 and CH4 and produce organic matter.

  8. Organic Chemistry Software from COMPress.

    ERIC Educational Resources Information Center

    Ball, Sister Isabel

    1982-01-01

    Reviews three organic chemistry computer programs for TRS-80 and Apple microcomputers. Programs include "Introduction to Organic Chemistry,""Qualitative Organic Analysis," and a game called "Chemrain." Indicates that all three produce a readable screen, require exact responses, use graphics in an appealingly and…

  9. Organic Experiments for Introductory Chemistry.

    ERIC Educational Resources Information Center

    Rayner-Canham, Geoff

    1985-01-01

    Describes test-tube organic chemistry procedures (using comparatively safe reagents) for the beginning student. These procedures are used to: examine differences between saturated and unsaturated hydrocarbons; compare structural isomers; and compare organic and inorganic acids and bases. (DH)

  10. Organic Chemistry for the Gifted.

    ERIC Educational Resources Information Center

    deBeer, W. H. J.

    In response to a serious shortage of chemists in South Africa, gifted secondary school students are enrolled in an enrichment program in organic chemistry and encouraged to consider chemistry or one of its related fields as a career. The introductory portion of the program involves approximately 90 hours over a 3-year period while the advanced…

  11. Mass spectrometry. [in organic chemistry

    NASA Technical Reports Server (NTRS)

    Burlingame, A. L.; Shackleton, C. H. L.; Howe, I.; Chizhov, O. S.

    1978-01-01

    A review of mass spectrometry in organic chemistry is given, dealing with advances in instrumentation and computer techniques, selected topics in gas-phase ion chemistry, and applications in such fields as biomedicine, natural-product studies, and environmental pollution analysis. Innovative techniques and instrumentation are discussed, along with chromatographic-mass spectrometric on-line computer techniques, mass spectral interpretation and management techniques, and such topics in gas-phase ion chemistry as electron-impact ionization and decomposition, photoionization, field ionization and desorption, high-pressure mass spectrometry, ion cyclotron resonance, and isomerization reactions of organic ions. Applications of mass spectrometry are examined with respect to bio-oligomers and their constituents, biomedically important substances, microbiology, environmental organic analysis, and organic geochemistry.

  12. Organic chemistry in space

    NASA Technical Reports Server (NTRS)

    Johnson, R. D.

    1977-01-01

    Organic cosmochemistry, organic materials in space exploration, and biochemistry of man in space are briefly surveyed. A model of Jupiter's atmosphere is considered, and the search for organic molecules in the solar system and in interstellar space is discussed. Materials and analytical techniques relevant to space exploration are indicated, and the blood and urine analyses performed on Skylab are described.

  13. Organic Chemistry Self Instructional Package 1: Review of General Chemistry.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet is one of a series of 17 developed at Prince George's Community College, Largo, Maryland. It provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  14. Titan's organic chemistry

    NASA Technical Reports Server (NTRS)

    Sagan, C.; Thompson, W. R.; Khare, B. N.

    1985-01-01

    Voyager discovered nine simple organic molecules in the atmosphere of Titan. Complex organic solids, called tholins, produced by irradiation of the simulated Titanian atmosphere, are consistent with measured properties of Titan from ultraviolet to microwave frequencies and are the likely main constituents of the observed red aerosols. The tholins contain many of the organic building blocks central to life on earth. At least 100-m, and possibly kms thicknesses of complex organics have been produced on Titan during the age of the solar system, and may exist today as submarine deposits beneath an extensive ocean of simple hydrocarbons.

  15. Perspectives on Computational Organic Chemistry

    PubMed Central

    Streitwieser, Andrew

    2009-01-01

    The author reviews how his early love for theoretical organic chemistry led to experimental research and the extended search for quantitative correlations between experiment and quantum calculations. The experimental work led to ion pair acidities of alkali-organic compounds and most recently to equilibria and reactions of lithium and cesium enolates in THF. This chemistry is now being modeled by ab initio calculations. An important consideration is the treatment of solvation in which coordination of the alkali cation with the ether solvent plays a major role. PMID:19518150

  16. Soil Organic Chemistry.

    ERIC Educational Resources Information Center

    Anderson, G.

    1979-01-01

    A brief review is presented of some of the organic compounds and reactions that occur in soil. Included are nitrogenous compounds, compounds of phosphorus and sulfur, carbohydrates, phenolic compounds, and aliphatic acids. (BB)

  17. Interstellar organic chemistry.

    NASA Technical Reports Server (NTRS)

    Sagan, C.

    1972-01-01

    Most of the interstellar organic molecules have been found in the large radio source Sagittarius B2 toward the galactic center, and in such regions as W51 and the IR source in the Orion nebula. Questions of the reliability of molecular identifications are discussed together with aspects of organic synthesis in condensing clouds, degradational origin, synthesis on grains, UV natural selection, interstellar biology, and contributions to planetary biology.

  18. Organic Chemistry of Meteorites

    NASA Technical Reports Server (NTRS)

    Chang, S.; Morrison, David (Technical Monitor)

    1994-01-01

    Studies of the molecular structures and C,N,H-isotopic compositions of organic matter in meteorites reveal a complex history beginning in the parent interstellar cloud which spawned the solar system. Incorporation of interstellar dust and gas in the protosolar nebula followed by further thermal and aqueous processing on primordial parent bodies of carbonaceous, meteorites have produced an inventory of diverse organic compounds including classes now utilized in biochemistry. This inventory represents one possible set of reactants for chemical models for the origin of living systems on the early Earth. Evidence bearing on the history of meteoritic organic matter from astronomical observations and laboratory investigations will be reviewed and future research directions discussed.

  19. Radiation Chemistry in Organized Assemblies.

    ERIC Educational Resources Information Center

    Thomas, J. K.; Chen, T. S.

    1981-01-01

    Expands the basic concepts regarding the radiation chemistry of simple aqueous systems to more complex, but well defined, organized assemblies. Discusses the differences in behavior in comparison to simple systems. Reviews these techniques: pulse radiolysis, laser flash, photolysis, and steady state irradiation by gamma rays or light. (CS)

  20. Photoredox Catalysis in Organic Chemistry

    PubMed Central

    2016-01-01

    In recent years, photoredox catalysis has come to the forefront in organic chemistry as a powerful strategy for the activation of small molecules. In a general sense, these approaches rely on the ability of metal complexes and organic dyes to convert visible light into chemical energy by engaging in single-electron transfer with organic substrates, thereby generating reactive intermediates. In this Perspective, we highlight the unique ability of photoredox catalysis to expedite the development of completely new reaction mechanisms, with particular emphasis placed on multicatalytic strategies that enable the construction of challenging carbon–carbon and carbon–heteroatom bonds. PMID:27477076

  1. Medicinal Chemistry/Pharmacology in Sophomore Organic Chemistry.

    ERIC Educational Resources Information Center

    Harrison, Aline M.

    1989-01-01

    Discussed is a series of lectures designed to illustrate the use of general organic chemical principles in molecular biology, introduce current research in interdisciplinary areas to the beginner, increase interest in organic chemistry, and bridge the gap between traditional organic chemistry, biology, and the consumer. An outline is presented.…

  2. Organic Chemistry Self Instructional Package 13: Dienes.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  3. Organic Chemistry Self Instructional Package 12: Alkynes.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  4. Organic Chemistry Self Instructional Package 2: Methane.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  5. Organic Chemistry Self Instructional Package 17: Arenes.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  6. Reaction-Map of Organic Chemistry

    ERIC Educational Resources Information Center

    Murov, Steven

    2007-01-01

    The Reaction-Map of Organic Chemistry lists all the most commonly studied reactions in organic chemistry on one page. The discussed Reaction-Map will act as another learning aide for the students, making the study of organic chemistry much easier.

  7. Chemistry of Covalent Organic Frameworks.

    PubMed

    Waller, Peter J; Gándara, Felipe; Yaghi, Omar M

    2015-12-15

    growing library of linkers amenable to the synthesis of COFs is now available, and new COFs and topologies made by reticular synthesis are being reported. Much research is also directed toward the development of new methods of linking organic building units to generate other crystalline COFs. These efforts promise not only new COF chemistry and materials, but also the chance to extend the precision of molecular covalent chemistry to extended solids.

  8. Incorporation of Medicinal Chemistry into the Organic Chemistry Curriculum

    ERIC Educational Resources Information Center

    Forbes, David C.

    2004-01-01

    Application of concepts presented in organic chemistry lecture using a virtual project involving the sythesis of medicinally important compounds is emphasized. The importance of reinforcing the concepts from lecture in lab, thus providing a powerful instructional means is discussed.

  9. Understanding Academic Performance in Organic Chemistry

    ERIC Educational Resources Information Center

    Szu, Evan; Nandagopal, Kiruthiga; Shavelson, Richard J.; Lopez, Enrique J.; Penn, John H.; Scharberg, Maureen; Hill, Geannine W.

    2011-01-01

    Successful completion of organic chemistry is a prerequisite for many graduate and professional programs in science, technology, engineering, and mathematics, yet the failure rate for this sequence of courses is notoriously high. To date, few studies have examined why some students succeed while others have difficulty in organic chemistry. This…

  10. Green chemistry oriented organic synthesis in water.

    PubMed

    Simon, Marc-Olivier; Li, Chao-Jun

    2012-02-21

    The use of water as solvent features many benefits such as improving reactivities and selectivities, simplifying the workup procedures, enabling the recycling of the catalyst and allowing mild reaction conditions and protecting-group free synthesis in addition to being benign itself. In addition, exploring organic chemistry in water can lead to uncommon reactivities and selectivities complementing the organic chemists' synthetic toolbox in organic solvents. Studying chemistry in water also allows insight to be gained into Nature's way of chemical synthesis. However, using water as solvent is not always green. This tutorial review briefly discusses organic synthesis in water with a Green Chemistry perspective.

  11. Undergraduate Organic Chemistry Laboratory Safety

    NASA Astrophysics Data System (ADS)

    Luckenbaugh, Raymond W.

    1996-11-01

    Each organic chemistry student should become familiar with the educational and governmental laboratory safety requirements. One method for teaching laboratory safety is to assign each student to locate safety resources for a specific class laboratory experiment. The student should obtain toxicity and hazardous information for all chemicals used or produced during the assigned experiment. For example, what is the LD50 or LC50 for each chemical? Are there any specific hazards for these chemicals, carcinogen, mutagen, teratogen, neurotixin, chronic toxin, corrosive, flammable, or explosive agent? The school's "Chemical Hygiene Plan", "Prudent Practices for Handling Hazardous Chemicals in the Laboratory" (National Academy Press), and "Laboratory Standards, Part 1910 - Occupational Safety and Health Standards" (Fed. Register 1/31/90, 55, 3227-3335) should be reviewed for laboratory safety requirements for the assigned experiment. For example, what are the procedures for safe handling of vacuum systems, if a vacuum distillation is used in the assigned experiment? The literature survey must be submitted to the laboratory instructor one week prior to the laboratory session for review and approval. The student should then give a short presentation to the class on the chemicals' toxicity and hazards and describe the safety precautions that must be followed. This procedure gives the student first-hand knowledge on how to find and evaluate information to meet laboartory safety requirements.

  12. Peer Mentoring in the General Chemistry and Organic Chemistry Laboratories: The Pinacol Rearrangement--An Exercise in NMR and IR Spectroscopy for General Chemistry and Organic Chemistry Laboratories

    ERIC Educational Resources Information Center

    Arrington, Caleb A.; Hill, Jameica B.; Radfar, Ramin; Whisnant, David M.; Bass, Charles G.

    2008-01-01

    This article describes a discovery experiment for general chemistry and organic chemistry labs. Although the pinacol rearrangement has been employed in undergraduate organic laboratories before, in this application organic chemistry students act as mentors to students of general chemistry. Students work together using distillation--a new technique…

  13. A Colorful Solubility Exercise for Organic Chemistry

    ERIC Educational Resources Information Center

    Shugrue, Christopher R.; Mentzen, Hans H., II; Linton, Brian R.

    2015-01-01

    A discovery chemistry laboratory has been developed for the introductory organic chemistry student to investigate the concepts of polarity, miscibility, solubility, and density. The simple procedure takes advantage of the solubility of two colored dyes in a series of solvents or solvent mixtures, and the diffusion of colors can be easily…

  14. Newer Reagents in Preparative Organic Chemistry.

    ERIC Educational Resources Information Center

    Grundy, J.

    1990-01-01

    Outlined is the development and use of oxidants for use in elementary organic chemistry classes. Discussed is the oxidation of alcohols to carbonyl compounds, and the oxidation of primary alcohols or aldehydes to carboxylic acids. (CW)

  15. Plasma chemistry and organic synthesis

    NASA Technical Reports Server (NTRS)

    Tezuka, M.

    1980-01-01

    The characteristic features of chemical reactions using low temperature plasmas are described and differentiated from those seen in other reaction systems. A number of examples of applications of plasma chemistry to synthetic reactions are mentioned. The production of amino acids by discharge reactions in hydrocarbon-ammonia-water systems is discussed, and its implications for the origins of life are mentioned.

  16. Organic chemistry in Titan's atmosphere

    NASA Technical Reports Server (NTRS)

    Scattergood, T.

    1982-01-01

    Laboratory photochemical simulations and other types of chemical simulations are discussed. The chemistry of methane, which is the major known constituent of Titan's atmosphere was examined with stress on what can be learned from photochemistry and particle irradiation. The composition of dust that comprises the haze layer was determined. Isotope fractionation in planetary atmospheres is also discussed.

  17. Love Story: Oxygen in Organic Chemistry

    ERIC Educational Resources Information Center

    Roberts, John D.

    1974-01-01

    Significant discoveries and developments regarding oxygen and organic compounds are recounted to show that research in this specific area is worthwhile and relevant and to point out that research in other areas of organic chemistry deserves continued encouragement as well. (DT)

  18. Titan: a laboratory for prebiological organic chemistry.

    PubMed

    Sagan, C; Thompson, W R; Khare, B N

    1992-01-01

    When we examine the atmospheres of the Jovian planets (Jupiter, Saturn, Uranus, and Neptune), the satellites in the outer solar system, comets, and even--through microwave and infrared spectroscopy--the cold dilute gas and grains between the stars, we find a rich organic chemistry, presumably abiological, not only in most of the solar system but throughout the Milky Way galaxy. In part because the composition and surface pressure of the Earth's atmosphere 4 x 10(9) years ago are unknown, laboratory experiments on prebiological organic chemistry are at best suggestive; but we can test our understanding by looking more closely at the observed extraterrestrial organic chemistry. The present Account is restricted to atmospheric organic chemistry, primarily on the large moon of Saturn. Titan is a test of our understanding of the organic chemistry of planetary atmospheres. Its atmospheric bulk composition (N2/CH4) is intermediate between the highly reducing (H2/He/CH4/NH3/H2O) atmospheres of the Jovian planets and the more oxidized (N2/CO2/H2O) atmospheres of the terrestrial planets Mars and Venus. It has long been recognized that Titan's organic chemistry may have some relevance to the events that led to the origin of life on Earth. But with Titan surface temperatures approximately equal to 94 K and pressures approximately equal to 1.6 bar, the oceans of the early Earth have no ready analogue on Titan. Nevertheless, tectonic events in the water ice-rich interior or impact melting and slow re-freezing may lead to an episodic availability of liquid water. Indeed, the latter process is the equivalent of a approximately 10(3)-year-duration shallow aqueous sea over the entire surface of Titan.

  19. Titan: a laboratory for prebiological organic chemistry

    NASA Technical Reports Server (NTRS)

    Sagan, C.; Thompson, W. R.; Khare, B. N.

    1992-01-01

    When we examine the atmospheres of the Jovian planets (Jupiter, Saturn, Uranus, and Neptune), the satellites in the outer solar system, comets, and even--through microwave and infrared spectroscopy--the cold dilute gas and grains between the stars, we find a rich organic chemistry, presumably abiological, not only in most of the solar system but throughout the Milky Way galaxy. In part because the composition and surface pressure of the Earth's atmosphere 4 x 10(9) years ago are unknown, laboratory experiments on prebiological organic chemistry are at best suggestive; but we can test our understanding by looking more closely at the observed extraterrestrial organic chemistry. The present Account is restricted to atmospheric organic chemistry, primarily on the large moon of Saturn. Titan is a test of our understanding of the organic chemistry of planetary atmospheres. Its atmospheric bulk composition (N2/CH4) is intermediate between the highly reducing (H2/He/CH4/NH3/H2O) atmospheres of the Jovian planets and the more oxidized (N2/CO2/H2O) atmospheres of the terrestrial planets Mars and Venus. It has long been recognized that Titan's organic chemistry may have some relevance to the events that led to the origin of life on Earth. But with Titan surface temperatures approximately equal to 94 K and pressures approximately equal to 1.6 bar, the oceans of the early Earth have no ready analogue on Titan. Nevertheless, tectonic events in the water ice-rich interior or impact melting and slow re-freezing may lead to an episodic availability of liquid water. Indeed, the latter process is the equivalent of a approximately 10(3)-year-duration shallow aqueous sea over the entire surface of Titan.

  20. Ethical Issues in Organic Chemistry.

    ERIC Educational Resources Information Center

    Coad, Peter; Coad, Raylene

    1985-01-01

    Suggests that a literature survey can alert students to real-life ethical problems surrounding many organic compounds. Topic areas students could explore include: hazards in the workplace, toxic chemicals, and nerve gas structures. Background information and an extensive bibliography are given. (DH)

  1. Measuring Student Performance in General Organic Chemistry

    ERIC Educational Resources Information Center

    Austin, Ara C.; Ben-Daat, Hagit; Zhu, Mary; Atkinson, Robert; Barrows, Nathan; Gould, Ian R.

    2015-01-01

    Student performance in general organic chemistry courses is determined by a wide range of factors including cognitive ability, motivation and cultural capital. Previous work on cognitive factors has tended to focus on specific areas rather than exploring performance across all problem types and cognitive skills. In this study, we have categorized…

  2. Experimental interstellar organic chemistry - Preliminary findings

    NASA Technical Reports Server (NTRS)

    Khare, B. N.; Sagan, C.

    1973-01-01

    Review of the results of some explicit experimental simulation of interstellar organic chemistry consisting in low-temperature high-vacuum UV irradiation of condensed simple gases known or suspected to be present in the interstellar medium. The results include the finding that acetonitrile may be present in the interstellar medium. The implication of this and other findings are discussed.

  3. Organic Chemistry in Action! What Is the Reaction?

    ERIC Educational Resources Information Center

    O'Dwyer, Anne; Childs, Peter

    2015-01-01

    The "Organic Chemistry in Action!" ("OCIA!") program is a set of teaching resources designed to facilitate the teaching and learning of introductory level organic chemistry. The "OCIA!" program was developed in collaboration with practicing and experienced chemistry teachers, using findings from Chemistry Education…

  4. Titan's organic chemistry: Results of simulation experiments

    NASA Technical Reports Server (NTRS)

    Sagan, Carl; Thompson, W. Reid; Khare, Bishun N.

    1992-01-01

    Recent low pressure continuous low plasma discharge simulations of the auroral electron driven organic chemistry in Titan's mesosphere are reviewed. These simulations yielded results in good accord with Voyager observations of gas phase organic species. Optical constants of the brownish solid tholins produced in similar experiments are in good accord with Voyager observations of the Titan haze. Titan tholins are rich in prebiotic organic constituents; the Huygens entry probe may shed light on some of the processes that led to the origin of life on Earth.

  5. Cellular uptake: lessons from supramolecular organic chemistry.

    PubMed

    Gasparini, Giulio; Bang, Eun-Kyoung; Montenegro, Javier; Matile, Stefan

    2015-07-04

    The objective of this Feature Article is to reflect on the importance of established and emerging principles of supramolecular organic chemistry to address one of the most persistent problems in life sciences. The main topic is dynamic covalent chemistry on cell surfaces, particularly disulfide exchange for thiol-mediated uptake. Examples of boronate and hydrazone exchange are added for contrast, comparison and completion. Of equal importance are the discussions of proximity effects in polyions and counterion hopping, and more recent highlights on ring tension and ion pair-π interactions. These lessons from supramolecular organic chemistry apply to cell-penetrating peptides, particularly the origin of "arginine magic" and the "pyrenebutyrate trick," and the currently emerging complementary "disulfide magic" with cell-penetrating poly(disulfide)s. They further extend to the voltage gating of neuronal potassium channels, gene transfection, and the delivery of siRNA. The collected examples illustrate that the input from conceptually innovative chemistry is essential to address the true challenges in biology beyond incremental progress and random screening.

  6. Organic Chemistry Self Instructional Package 16: Aromatic Chemistry Effect of Substituents.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  7. Physical organic chemistry of supramolecular polymers.

    PubMed

    Serpe, Michael J; Craig, Stephen L

    2007-02-13

    Unlike the case of traditional covalent polymers, the entanglements that determine properties of supramolecular polymers are defined by very specific, intermolecular interactions. Recent work using modular molecular platforms to probe the mechanisms underlying mechanical response of supramolecular polymers is reviewed. The contributions of supramolecular kinetics, thermodynamics, and conformational flexibility to supramolecular polymer properties in solutions of discrete polymers, in networks, and at interfaces, are described. Molecule-to-material relationships are established through methods reminiscent of classic physical organic chemistry.

  8. Organic Chemistry Self Instructional Package 15: Benzene, Aromaticity.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  9. Organic Chemistry Self Instructional Package 11: Stereochemistry 2.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  10. Organic Chemistry Self Instructional Package 9: Alkenes-Reactions 1.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  11. Organic Chemistry Self Instructional Package 5: Alkanes Preparations and Reactions.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  12. Organic Chemistry Self Instructional Package 6: Stereochemistry 1.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  13. Organic Chemistry Self Instructional Package 14: Cyclic Compounds.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  14. Organic Chemistry Self Instructional Package 4: Alkanes-Nomenclature.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  15. Organic Chemistry Self Instructional Package 8: Alkenes-Preparations.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  16. Organic Chemistry Self Instructional Package 10: Alkenes-Reactions 2.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  17. Synthesis-Spectroscopy Roadmap Problems: Discovering Organic Chemistry

    ERIC Educational Resources Information Center

    Kurth, Laurie L.; Kurth, Mark J.

    2014-01-01

    Organic chemistry problems that interrelate and integrate synthesis with spectroscopy are presented. These synthesis-spectroscopy roadmap (SSR) problems uniquely engage second-year undergraduate organic chemistry students in the personal discovery of organic chemistry. SSR problems counter the memorize-or-bust strategy that many students tend to…

  18. Making Sense of the Arrow-Pushing Formalism among Chemistry Majors Enrolled in Organic Chemistry

    ERIC Educational Resources Information Center

    Ferguson, Robert; Bodner, George M.

    2008-01-01

    This paper reports results of a qualitative study of sixteen students enrolled in a second year organic chemistry course for chemistry and chemical engineering majors. The focus of the study was student use of the arrow-pushing formalism that plays a central role in both the teaching and practice of organic chemistry. The goal of the study was to…

  19. Form and Function: An Organic Chemistry Module. Teacher's Guide.

    ERIC Educational Resources Information Center

    Jarvis, Bruce; Mazzocchi, Paul; Hearle, Robert

    This teacher's guide is designed to provide science teachers with the necessary guidance and suggestions for teaching organic chemistry. In this book, the diverse field of organic chemistry modules is introduced. The material in this book can be integrated with the other modules in a sequence that helps students to see that chemistry is a unified…

  20. Atmospheric Chemistry of Micrometeoritic Organic Compounds

    NASA Technical Reports Server (NTRS)

    Kress, M. E.; Belle, C. L.; Pevyhouse, A. R.; Iraci, L. T.

    2011-01-01

    Micrometeorites approx.100 m in diameter deliver most of the Earth s annual accumulation of extraterrestrial material. These small particles are so strongly heated upon atmospheric entry that most of their volatile content is vaporized. Here we present preliminary results from two sets of experiments to investigate the fate of the organic fraction of micrometeorites. In the first set of experiments, 300 m particles of a CM carbonaceous chondrite were subject to flash pyrolysis, simulating atmospheric entry. In addition to CO and CO2, many organic compounds were released, including functionalized benzenes, hydrocarbons, and small polycyclic aromatic hydrocarbons. In the second set of experiments, we subjected two of these compounds to conditions that simulate the heterogeneous chemistry of Earth s upper atmosphere. We find evidence that meteor-derived compounds can follow reaction pathways leading to the formation of more complex organic compounds.

  1. Abiotic Organic Chemistry in Hydrothermal Systems.

    NASA Astrophysics Data System (ADS)

    Simoneit, B. R.; Rushdi, A. I.

    2004-12-01

    Abiotic organic chemistry in hydrothermal systems is of interest to biologists, geochemists and oceanographers. This chemistry consists of thermal alteration of organic matter and minor prebiotic synthesis of organic compounds. Thermal alteration has been extensively documented to yield petroleum and heavy bitumen products from contemporary organic detritus. Carbon dioxide, carbon monoxide, ammonia and sulfur species have been used as precursors in prebiotic synthesis experiments to organic compounds. These inorganic species are common components of hot spring gases and marine hydrothermal systems. It is of interest to further test their reactivities in reductive aqueous thermolysis. We have synthesized organic compounds (lipids) in aqueous solutions of oxalic acid, and with carbon disulfide or ammonium bicarbonate at temperatures from 175-400° C. The synthetic lipids from oxalic acid solutions consisted of n-alkanols, n-alkanoic acids, n-alkyl formates, n-alkanones, n-alkenes and n-alkanes, typically to C30 with no carbon number preferences. The products from CS2 in acidic aqueous solutions yielded cyclic thioalkanes, alkyl polysulfides, and thioesters with other numerous minor compounds. The synthesis products from oxalic acid and ammonium bicarbonate solutions were homologous series of n-alkyl amides, n-alkyl amines, n-alkanes and n-alkanoic acids, also to C30 with no carbon number predominance. Condensation (dehydration) reactions also occur under elevated temperatures in aqueous medium as tested by model reactions to form amide, ester and nitrile bonds. It is concluded that the abiotic formation of aliphatic lipids, condensation products (amides, esters, nitriles, and CS2 derivatives (alkyl polysulfides, cyclic polysulfides) is possible under hydrothermal conditions and warrants further studies.

  2. Organic Chemistry in Action! Developing an Intervention Program for Introductory Organic Chemistry to Improve Learners' Understanding, Interest, and Attitudes

    ERIC Educational Resources Information Center

    O'Dwyer, Anne; Childs, Peter

    2014-01-01

    The main areas of difficulty experienced by those teaching and learning organic chemistry at high school and introductory university level in Ireland have been identified, and the findings support previous studies in Ireland and globally. Using these findings and insights from chemistry education research (CER), the Organic Chemistry in Action!…

  3. Shock-induced chemistry in organic materials

    SciTech Connect

    Dattelbaum, Dana M; Sheffield, Steve; Engelke, Ray; Manner, Virginia; Chellappa, Raja; Yoo, Choong - Shik

    2011-01-20

    The combined 'extreme' environments of high pressure, temperature, and strain rates, encountered under shock loading, offer enormous potential for the discovery of new paradigms in chemical reactivity not possible under more benign conditions. All organic materials are expected to react under these conditions, yet we currently understand very little about the first bond-breaking steps behind the shock front, such as in the shock initiation of explosives, or shock-induced reactivity of other relevant materials. Here, I will present recent experimental results of shock-induced chemistry in a variety of organic materials under sustained shock conditions. A comparison between the reactivity of different structures is given, and a perspective on the kinetics of reaction completion under shock drives.

  4. Novel Aryne Chemistry in Organic Synthesis

    SciTech Connect

    Liu, Zhijian

    2006-12-12

    Arynes are among the most intensively studied systems in chemistry. However, many aspects of the chemistry of these reactive intermediates are not well understood yet and their use as reagents in synthetic organic chemistry has been somewhat limited, due to the harsh conditions needed to generate arynes and the often uncontrolled reactivity exhibited by these species. Recently, o-silylaryl triflates, which can generate the corresponding arynes under very mild reaction conditions, have been found very useful in organic synthesis. This thesis describes several novel and useful methodologies by employing arynes, which generate from o-silylaryl triflates, in organic synthesis. An efficient, reliable method for the N-arylation of amines, sulfonamides and carbamates, and the O-arylation of phenols and carboxylic acids is described in Chapter 1. Amines, sulfonamides, phenols, and carboxylic acids are good nucleophiles, which can react with arynes generated from a-silylaryl triflates to afford the corresponding N- and O-arylated products in very high yields. The regioselectivity of unsymmetrical arynes has also been studied. A lot of useful, functional groups can tolerate our reaction conditions. Carbazoles and dibenzofurans are important heteroaromatic compounds, which have a variety of biological activities. A variety of substituted carbazoles and dibenzofwans are readily prepared in good to excellent yields starting with the corresponding o-iodoanilines or o-iodophenols and o-silylaryl triflates by a treatment with CsF, followed by a Pd-catalyzed cyclization, which overall provides a one-pot, two-step process. By using this methodology, the carbazole alkaloid mukonine has been concisely synthesized in a very good yield. Insertion of an aryne into a σ-bond between a nucleophile and an electrophile (Nu-E) should potentially be a very beneficial process from the standpoint of organic synthesis. A variety of substituted ketones and sulfoxides have been synthesized in good

  5. Cocrystal Controlled Solid-State Synthesis: A Green Chemistry Experiment for Undergraduate Organic Chemistry

    ERIC Educational Resources Information Center

    Cheney, Miranda L.; Zaworotko, Michael J.; Beaton, Steve; Singer, Robert D.

    2008-01-01

    Green chemistry has become an important area of concern for all chemists from practitioners in the pharmaceutical industry to professors and the students they teach and is now being incorporated into lectures of general and organic chemistry courses. However, there are relatively few green chemistry experiments that are easily incorporated into…

  6. Understanding the Impact of a General Chemistry Course on Students' Transition to Organic Chemistry

    ERIC Educational Resources Information Center

    Collins-Webb, Alexandra; Jeffery, Kathleen A.; Sweeder, Ryan D.

    2016-01-01

    The move from general chemistry to organic chemistry can be a challenge for students as it often involves a transition from quantitatively-oriented to mechanistically-oriented thinking. This study found that the design of the general chemistry course can change the student experience of this transition as assessed by a reflective survey. The…

  7. Benchmarking Problems Used in Second Year Level Organic Chemistry Instruction

    ERIC Educational Resources Information Center

    Raker, Jeffrey R.; Towns, Marcy H.

    2010-01-01

    Investigations of the problem types used in college-level general chemistry examinations have been reported in this Journal and were first reported in the "Journal of Chemical Education" in 1924. This study extends the findings from general chemistry to the problems of four college-level organic chemistry courses. Three problem…

  8. Atmospheric Prebiotic Chemistry and Organic Hazes

    NASA Technical Reports Server (NTRS)

    Trainer, Melissa G.

    2012-01-01

    Earth's atmospheric composition at the time of the origin of life is not known, but it has often been suggested that chemical transformation of reactive species in the atmosphere was a significant source of pre biotic organic molecules. Experimental and theoretical studies over the past half century have shown that atmospheric synthesis can yield molecules such as amino acids and nucleobases, but these processes are very sensitive to gas composition and energy source. Abiotic synthesis of organic molecules is more productive in reduced atmospheres, yet the primitive Earth may not have been as reducing as earlier workers assumed, and recent research has reflected this shift in thinking. This work provides a survey of the range of chemical products that can be produced given a set of atmospheric conditions, with a particular focus on recent reports. Intertwined with the discussion of atmospheric synthesis is the consideration of an organic haze layer, which has been suggested as a possible ultraviolet shield on the anoxic early Earth. Since such a haze layer - if formed - would serve as a reservoir for organic molecules, the chemical composition of the aerosol should be closely examined. The results highlighted here show that a variety of products can be formed in mildly reducing or even neutral atmospheres, demonstrating that contributions of atmospheric synthesis to the organic inventory on early Earth should not be discounted. This review intends to bridge current knowledge of the range of possible atmospheric conditions in the prebiotic environment and pathways for synthesis under such conditions by examining the possible products of organic chemistry in the early atmosphere.

  9. Atmospheric Prebiotic Chemistry and Organic Hazes

    PubMed Central

    Trainer, Melissa G.

    2013-01-01

    Earth’s atmospheric composition at the time of the origin of life is not known, but it has often been suggested that chemical transformation of reactive species in the atmosphere was a significant source of prebiotic organic molecules. Experimental and theoretical studies over the past half century have shown that atmospheric synthesis can yield molecules such as amino acids and nucleobases, but these processes are very sensitive to gas composition and energy source. Abiotic synthesis of organic molecules is more productive in reduced atmospheres, yet the primitive Earth may not have been as reducing as earlier workers assumed, and recent research has reflected this shift in thinking. This work provides a survey of the range of chemical products that can be produced given a set of atmospheric conditions, with a particular focus on recent reports. Intertwined with the discussion of atmospheric synthesis is the consideration of an organic haze layer, which has been suggested as a possible ultraviolet shield on the anoxic early Earth. Since such a haze layer – if formed – would serve as a reservoir for organic molecules, the chemical composition of the aerosol should be closely examined. The results highlighted here show that a variety of products can be formed in mildly reducing or even neutral atmospheres, demonstrating that contributions of atmospheric synthesis to the organic inventory on early Earth should not be discounted. This review intends to bridge current knowledge of the range of possible atmospheric conditions in the prebiotic environment and pathways for synthesis under such conditions by examining the possible products of organic chemistry in the early atmosphere. PMID:24143126

  10. Atmospheric Prebiotic Chemistry and Organic Hazes.

    PubMed

    Trainer, Melissa G

    2013-08-01

    Earth's atmospheric composition at the time of the origin of life is not known, but it has often been suggested that chemical transformation of reactive species in the atmosphere was a significant source of prebiotic organic molecules. Experimental and theoretical studies over the past half century have shown that atmospheric synthesis can yield molecules such as amino acids and nucleobases, but these processes are very sensitive to gas composition and energy source. Abiotic synthesis of organic molecules is more productive in reduced atmospheres, yet the primitive Earth may not have been as reducing as earlier workers assumed, and recent research has reflected this shift in thinking. This work provides a survey of the range of chemical products that can be produced given a set of atmospheric conditions, with a particular focus on recent reports. Intertwined with the discussion of atmospheric synthesis is the consideration of an organic haze layer, which has been suggested as a possible ultraviolet shield on the anoxic early Earth. Since such a haze layer - if formed - would serve as a reservoir for organic molecules, the chemical composition of the aerosol should be closely examined. The results highlighted here show that a variety of products can be formed in mildly reducing or even neutral atmospheres, demonstrating that contributions of atmospheric synthesis to the organic inventory on early Earth should not be discounted. This review intends to bridge current knowledge of the range of possible atmospheric conditions in the prebiotic environment and pathways for synthesis under such conditions by examining the possible products of organic chemistry in the early atmosphere.

  11. Distributed Pore Chemistry in Porous Organic Polymers

    NASA Technical Reports Server (NTRS)

    Koontz, Steven L. (Inventor)

    1998-01-01

    A method for making a biocompatible polymer article using a uniform atomic oxygen treatment is disclosed. The sub-strate may be subsequently optionally grated with a compatibilizing compound. Compatibilizing compounds may include proteins, phosphorylcholine groups, platelet adhesion preventing polymers, albumin adhesion promoters, and the like. The compatibilized substrate may also have a living cell layer adhered thereto. The atomic oxygen is preferably produced by a flowing afterglow microwave discharge, wherein the substrate resides in a sidearm out of the plasma. Also, methods for culturing cells for various purposes using the various membranes are disclosed as well. Also disclosed are porous organic polymers having a distributed pore chemistry (DPC) comprising hydrophilic and hydrophobic region, and a method for making the DPC by exposing the polymer to atomic oxygen wherein the rate of hydrophilization is greater than the rate of mass loss.

  12. Distributed Pore Chemistry in Porous Organic Polymers

    NASA Technical Reports Server (NTRS)

    Koontz, Steven L. (Inventor)

    1999-01-01

    A method for making a biocompatible polymer article using a uniform atomic oxygen treatment is disclosed. The substrate may be subsequently optionally grated with a compatibilizing compound. Compatibilizing compounds may include proteins, phosphorylcholine groups, platelet adhesion preventing polymers, albumin adhesion promoters, and the like. The compatibilized substrate may also have a living cell layer adhered thereto. The atomic oxygen is preferably produced by a flowing afterglow microwave discharge. wherein the substrate resides in a sidearm out of the plasma. Also, methods for culturing cells for various purposes using the various membranes are disclosed as well. Also disclosed are porous organic polymers having a distributed pore chemistry (DPC) comprising hydrophilic and hydrophobic regions. and a method for making the DPC by exposing the polymer to atomic oxygen wherein the rate of hydrophilization is greater than the rate of mass loss.

  13. Form and Function: An Organic Chemistry Module.

    ERIC Educational Resources Information Center

    Jarvis, Bruce; Mazzocchi, Paul

    This book is one in the series of Interdisciplinary Approaches to Chemistry (IAC) designed to help students discover that chemistry is a lively science and actively used to pursue solutions to the important problems of today. It is expected for students to see how chemistry takes place continuously all around and to readily understand the daily…

  14. Comparing Carbonyl Chemistry in Comprehensive Introductory Organic Chemistry Textbooks

    ERIC Educational Resources Information Center

    Nelson, Donna J.; Kumar, Ravi; Ramasamy, Saravanan

    2015-01-01

    Learning the chemistry of compounds containing carbonyl groups is difficult for undergraduate students partly because of a convolution of multiple possible reaction sites, competitive reactions taking place at those sites, different criteria needed to discern between the mechanisms of these reactions, and no straightforward selection method…

  15. Representational Translation with Concrete Models in Organic Chemistry

    ERIC Educational Resources Information Center

    Stull, Andrew T.; Hegarty, Mary; Dixon, Bonnie; Stieff, Mike

    2012-01-01

    In representation-rich domains such as organic chemistry, students must be facile and accurate when translating between different 2D representations, such as diagrams. We hypothesized that translating between organic chemistry diagrams would be more accurate when concrete models were used because difficult mental processes could be augmented by…

  16. Organic Chemistry Trivia: A Way to Interest Nonchemistry Majors

    ERIC Educational Resources Information Center

    Farmer, Steven C.

    2011-01-01

    The use of in-class stories is an excellent way to keep a class interested in subject matter. Many organic chemistry classes are populated by nonchemistry majors, such as pre-med, pre-pharm, and biology students. Trivia questions are presented that are designed to show how organic chemistry is an important subject to students regardless of their…

  17. Students' Understanding of Alkyl Halide Reactions in Undergraduate Organic Chemistry

    ERIC Educational Resources Information Center

    Cruz-Ramirez de Arellano, Daniel

    2013-01-01

    Organic chemistry is an essential subject for many undergraduate students completing degrees in science, engineering, and pre-professional programs. However, students often struggle with the concepts and skills required to successfully solve organic chemistry exercises. Since alkyl halides are traditionally the first functional group that is…

  18. Mass spectrometry. [in organic ion and biorganic chemistry and medicine

    NASA Technical Reports Server (NTRS)

    Burlingame, A. L.; Cox, R. E.; Derrick, P. J.

    1974-01-01

    Review of the present status of mass spectrometry in the light of pertinent recent publications spanning the period from December 1971 to January 1974. Following an initial survey of techniques, instruments, and computer applications, a sharp distinction is made between the chemistry of organic (radical-)ions and analytical applications in biorganic chemistry and medicine. The emphasis is on the chemistry of organic (radical-)ions at the expense of inorganic, organometallic, and surface ion chemistry. Biochemistry and medicine are chosen because of their contemporary importance and because of the stupendous contributions of mass spectroscopy to these fields in the past two years. In the review of gas-phase organic ion chemistry, special attention is given to studies making significant contributions to the understanding of ion chemistry.

  19. Flipping organic chemistry course: Possibilities and challenges

    NASA Astrophysics Data System (ADS)

    Cha, J.; Kim, H. B.

    2016-06-01

    The flipped classroom approach was applied to an introductory organic chemistry course. A total of 76 video clips (15 hours of running time) were developed and delivered to 41 sophomores (21 females and 20 males) through Youtube in addition to the university's learning management system. The students were asked to preview the lecture contents before each class by watching a pre-class video. For in-class activities, exercise problems were presented to groups of 3-5 students. An instructor and a teaching assistant guided each group to solve problems cooperatively, monitored the students’ group activity and answered their questions. At the end of every chapter, the students were asked to evaluate their group work and personal preparedness for the class and also to write a short reflective journal. The muddiest point of each chapter, i.e., the topic posing the most difficulty to students’ understanding, was surveyed through Google Forms®. The students liked watching the videos before each class and performing student-centered, in-class group activities but a few limitations were also found and reported.

  20. 11th National Meeting of Organic Chemistry and 4th Meeting of Therapeutic Chemistry

    PubMed Central

    Sousa, Maria Emília; Araújo, Maria João; do Vale, Maria Luísa; Andrade, Paula B.; Branco, Paula; Gomes, Paula; Moreira, Rui; Pinho e Melo, Teresa M.V.D.; Freitas, Victor

    2016-01-01

    For the first time under the auspices of Sociedade Portuguesa de Química, the competences of two important fields of Chemistry are brought together into a single event, the 11st National Organic Chemistry Meeting and the the 4th National Medicinal Chemistry Meeting, to highlight complementarities and to promote new synergies. Abstracts of plenary lectures, oral communications, and posters presented during the meeting are collected in this report. PMID:27102166

  1. 11(th) National Meeting of Organic Chemistry and 4(th) Meeting of Therapeutic Chemistry.

    PubMed

    Sousa, Maria Emília; Araújo, Maria João; do Vale, Maria Luísa; Andrade, Paula B; Branco, Paula; Gomes, Paula; Moreira, Rui; Pinho E Melo, Teresa M V D; Freitas, Victor

    2016-03-17

    For the first time under the auspices of Sociedade Portuguesa de Química, the competences of two important fields of Chemistry are brought together into a single event, the 11st National Organic Chemistry Meeting and the the 4th National Medicinal Chemistry Meeting, to highlight complementarities and to promote new synergies. Abstracts of plenary lectures, oral communications, and posters presented during the meeting are collected in this report.

  2. Modeling the Explicit Chemistry of Anthropogenic and Biogenic Organic Aerosols

    SciTech Connect

    Madronich, Sasha

    2015-12-09

    The atmospheric burden of Secondary Organic Aerosols (SOA) remains one of the most important yet uncertain aspects of the radiative forcing of climate. This grant focused on improving our quantitative understanding of SOA formation and evolution, by developing, applying, and improving a highly detailed model of atmospheric organic chemistry, the Generation of Explicit Chemistry and Kinetics of Organics in the Atmosphere (GECKO-A) model. Eleven (11) publications have resulted from this grant.

  3. Advanced Organic Chemistry: Reactions and Mechanisms (by Bernard Miller)

    NASA Astrophysics Data System (ADS)

    Berger, Daniel

    1998-12-01

    Prentice Hall: Upper Saddle River, NJ, 1998. 338 pp, index. ISBN 0-13-373275-4. $59.00. Recently several short texts on intermediate organic chemistry have been published, intended for use in one-term courses for advanced undergraduates and for graduate students who need more background before taking a graduate-level course. These books fill a need not fully met by graduate-level texts such as Lowry and Richardson's Mechanism and Theory in Organic Chemistry or Carey and Sundberg's Advanced Organic Chemistry.

  4. Neural Networks for the Prediction of Organic Chemistry Reactions

    PubMed Central

    2016-01-01

    Reaction prediction remains one of the major challenges for organic chemistry and is a prerequisite for efficient synthetic planning. It is desirable to develop algorithms that, like humans, “learn” from being exposed to examples of the application of the rules of organic chemistry. We explore the use of neural networks for predicting reaction types, using a new reaction fingerprinting method. We combine this predictor with SMARTS transformations to build a system which, given a set of reagents and reactants, predicts the likely products. We test this method on problems from a popular organic chemistry textbook. PMID:27800555

  5. Neural Networks for the Prediction of Organic Chemistry Reactions.

    PubMed

    Wei, Jennifer N; Duvenaud, David; Aspuru-Guzik, Alán

    2016-10-26

    Reaction prediction remains one of the major challenges for organic chemistry and is a prerequisite for efficient synthetic planning. It is desirable to develop algorithms that, like humans, "learn" from being exposed to examples of the application of the rules of organic chemistry. We explore the use of neural networks for predicting reaction types, using a new reaction fingerprinting method. We combine this predictor with SMARTS transformations to build a system which, given a set of reagents and reactants, predicts the likely products. We test this method on problems from a popular organic chemistry textbook.

  6. Improving Student Performance in Organic Chemistry: Help Seeking Behaviors and Prior Chemistry Aptitude

    ERIC Educational Resources Information Center

    Horowitz, Gail; Rabin, Laura A.; Brodale, Donald L.

    2013-01-01

    Organic Chemistry is perceived to be one of the most challenging of undergraduate science courses, and attrition from this course may impact decisions about pursuing a professional or academic career in the biomedical and related sciences. Research suggests that chemistry students who are strategic help seekers may outperform those students who…

  7. Caring for the Environment while Teaching Organic Chemistry

    ERIC Educational Resources Information Center

    Santos, Elvira Santos; Gavilan Garcia, Irma Cruz; Lejarazo Gomez, Eva Florencia

    2004-01-01

    A comprehensive program in the field of green chemistry, which concentrates on processing and managing of wastes produced during laboratory experiments, is presented. The primary aim of the program is to instill a sense of responsibility and a concern for the environment through organic chemistry education.

  8. Organic First: A Biology-Friendly Chemistry Curriculum

    ERIC Educational Resources Information Center

    Reingold, I. David

    2005-01-01

    In this essay, the author describes to biologists the advantages of organic-first curriculum, on the assumption that few biologists are regular readers of "Journal of Chemistry Education" and therefore are probably unaware of the method for integrating chemistry and biology curricula. The author begins with the assumption that the majority of…

  9. Creatine Synthesis: An Undergraduate Organic Chemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Smith, Andri L.; Tan, Paula

    2006-01-01

    Students in introductory chemistry classes typically appreciate seeing the connection between course content and the "real world". For this reason, we have developed a synthesis of creatine monohydrate--a popular supplement used in sports requiring short bursts of energy--for introductory organic chemistry laboratory courses. Creatine monohydrate…

  10. CARBINOLAMINES AND GEMINAL DIOLS IN AQUEOUS ENVIRONMENTAL ORGANIC CHEMISTRY

    EPA Science Inventory

    Organic chemistry textbooks generally treat geminal diols as curiosities-exceptions to the stability of the C=O double bond. However, most aldehydes of environmental significance, to wit, trichloroethanal (chloral), methanala (formaldehyde), ethanal (acetaldehyde), and propanal ...

  11. The Application of Physical Organic Chemistry to Biochemical Problems.

    ERIC Educational Resources Information Center

    Westheimer, Frank

    1986-01-01

    Presents the synthesis of the science of enzymology from application of the concepts of physical organic chemistry from a historical perspective. Summarizes enzyme and coenzyme mechanisms elucidated prior to 1963. (JM)

  12. The Year-Long First Course in Organic Chemistry.

    ERIC Educational Resources Information Center

    Johnson, A. William

    1990-01-01

    Reported are the results of a study of organic chemistry courses at 33 different undergraduate colleges and universities. Details of the site visits including lecture and laboratory components of the courses are provided. (CW)

  13. A Novel Philosophy for a First Course in Organic Chemistry.

    ERIC Educational Resources Information Center

    Newman, Melvin S.

    1982-01-01

    Focusing on research is suggested as an approach for teaching organic chemistry for nonmajors. Topics of saturated hydrocarbons and unsaturated hydrocarbons are used as examples to illustrate the approach. (SK)

  14. Improvements to the Characterization of Organic Nitrogen Chemistry

    EPA Science Inventory

    Excess atmospheric nitrogen deposition can cause significant harmful effects to ecosystems. Organic nitrogen deposition can be an important contributor to the total nitrogen budget, contributing 10-30%, however there are large uncertainties in the chemistry and deposition of thes...

  15. Searching the Chemistry Files for Synthetic Organic Chemistry.

    ERIC Educational Resources Information Center

    Antony, Arthur

    1978-01-01

    Examines a number of searches dealing with the synthesis of organic compounds which the author performed on CA CONDENSATES and CASIA data bases (on DIALOG) at the request of users. Results show that a combined use provides the users with a more satisfying result even if the larger output contains some undesired citations. (JD)

  16. Topic Sequence and Emphasis Variability of Selected Organic Chemistry Textbooks

    ERIC Educational Resources Information Center

    Houseknecht, Justin B.

    2010-01-01

    Textbook choice has a significant effect upon course success. Among the factors that influence this decision, two of the most important are material organization and emphasis. This paper examines the sequencing of 19 organic chemistry topics, 21 concepts and skills, and 7 biological topics within nine of the currently available organic textbooks.…

  17. Novel Organic Synthesis through Ultrafast Chemistry.

    PubMed

    Wirth, Thomas

    2017-01-16

    How fast are flashes? The field of flow chemistry has recently received increasing attention owing to the availability of commercial flow equipment. New syntheses with very short-lived intermediates have been enabled by sub-millisecond mixing and reaction regimes in tailor-made flow devices.

  18. Positive Impacts Using POGIL in Organic Chemistry

    ERIC Educational Resources Information Center

    Hein, Sara M.

    2012-01-01

    A student-centered learning technique, process-oriented, guided-inquiry learning (POGIL), has been developed as a pedagogical technique that facilitates collaborative and cooperative learning in the chemistry classroom. With the use of this technique, students enhance their higher-order thinking skills and process skills synergistically. In…

  19. Organic chemistry in the atmosphere. [laboratory modeling of Titan atmosphere

    NASA Technical Reports Server (NTRS)

    Sagan, C.

    1974-01-01

    The existence of an at least moderately complex organic chemistry on Titan is stipulated based on clear evidence of methane, and at least presumptive evidence of hydrogen in its atmosphere. The ratio of methane to hydrogen is the highest of any atmosphere in the solar system. Irradiation of hydrogen/methane mixtures produces aromatic and aliphatic hydrocarbons. A very reasonable hypothesis assumes that the red cloud cover of Titan is made of organic chemicals. Two-carbon hydrocarbons experimentally produced from irradiated mixtures of methane, ammonia, water, and hydrogen bear out the possible organic chemistry of the Titanian environment.

  20. Organic chemistry and biology of the interstellar medium

    NASA Technical Reports Server (NTRS)

    Sagan, C.

    1973-01-01

    Interstellar organic chemistry is discussed as the field of study emerging from the discovery of microwave lines of formaldehyde and of hydrogen cyanide in the interstellar medium. The reliability of molecular identifications and comparisons of interstellar and cometary compounds are considered, along with the degradational origin of simple organics. It is pointed out that the contribution of interstellar organic chemistry to problems in biology is not substantive but analogical. The interstellar medium reveals the operation of chemical processes which, on earth and perhaps on vast numbers of planets throughout the universe, led to the origin of life, but the actual molecules of the interstellar medium are unlikely to play any significant biological role.

  1. Synthesis Road Map Problems in Organic Chemistry

    ERIC Educational Resources Information Center

    Schaller, Chris P.; Graham, Kate J.; Jones, T. Nicholas

    2014-01-01

    Road map problems ask students to integrate their knowledge of organic reactions with pattern recognition skills to "fill in the blanks" in the synthesis of an organic compound. Students are asked to identify familiar organic reactions in unfamiliar contexts. A practical context, such as a medicinally useful target compound, helps…

  2. A Multistep Synthesis for an Advanced Undergraduate Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Chang Ji; Peters, Dennis G.

    2006-01-01

    Multistep syntheses are often important components of the undergraduate organic laboratory experience and a three-step synthesis of 5-(2-sulfhydrylethyl) salicylaldehyde was described. The experiment is useful as a special project for an advanced undergraduate organic chemistry laboratory course and offers opportunities for students to master a…

  3. Building Bridges between Science Courses Using Honors Organic Chemistry Projects

    ERIC Educational Resources Information Center

    Hickey, Timothy; Pontrello, Jason

    2016-01-01

    Introductory undergraduate science courses are traditionally offered as distinct units without formalized student interaction between classes. To bridge science courses, the authors used three Honors Organic Chemistry projects paired with other science courses. The honors students delivered presentations to mainstream organic course students and…

  4. Undergraduate Oral Examinations in a University Organic Chemistry Curriculum

    ERIC Educational Resources Information Center

    Dicks, Andrew P.; Lautens, Mark; Koroluk, Katherine J.; Skonieczny, Stanislaw

    2012-01-01

    This article describes the successful implementation of an oral examination format in the organic chemistry curriculum at the University of Toronto. Oral examinations are used to replace traditional written midterm examinations in several courses. In an introductory organic class, each student is allotted 15 min to individually discuss one…

  5. Saying What You Mean: Teaching Mechanisms in Organic Chemistry

    ERIC Educational Resources Information Center

    Friesen, J. Brent

    2008-01-01

    Organic reactions in introductory organic chemistry courses are most commonly taught with a mechanism-based approach to the understanding of molecular reactivity. However, the effectiveness of the popular curved arrow representation to describe reaction mechanisms is often compromised by the overuse of shortcuts and obscure notation. The…

  6. Using Popular Nonfiction in Organic Chemistry: Teaching More than Content

    ERIC Educational Resources Information Center

    Amaral, Katie E.; Shibley, Ivan A., Jr.

    2010-01-01

    Assigning a popular nonfiction book as a supplemental text in organic chemistry can help students learn valuable skills. An analysis of student feedback on assignments related to a nonfiction book in two different organic courses revealed that students applied the information from the book, improved their communication skills, and were more…

  7. Students' understanding of alkyl halide reactions in undergraduate organic chemistry

    NASA Astrophysics Data System (ADS)

    Cruz-Ramirez de Arellano, Daniel

    Organic chemistry is an essential subject for many undergraduate students completing degrees in science, engineering, and pre-professional programs. However, students often struggle with the concepts and skills required to successfully solve organic chemistry exercises. Since alkyl halides are traditionally the first functional group that is studied in undergraduate organic chemistry courses, establishing a robust understanding of the concepts and reactions related to them can be beneficial in assuring students' success in organic chemistry courses. Therefore, the purpose of this study was to elucidate and describe students' understanding of alkyl halide reactions in an undergraduate organic chemistry course. Participants were interviewed using a think-aloud protocol in which they were given a set of exercises dealing with reactions and mechanisms of alkyl halide molecules in order to shed light on the students' understanding of these reactions and elucidate any gaps in understanding and incorrect warrants that may be present. These interviews were transcribed and analyzed using qualitative inquiry approaches. In general, the findings from this study show that the students exhibited gaps in understanding and incorrect warrants dealing with: (1) classifying substances as bases and/or nucleophiles, (2) assessing the basic or nucleophilic strength of substances, (3) accurately describing the electron movement of the steps that take place during alkyl halide reaction mechanisms, and (4) assessing the viability of their proposed reactive intermediates and breakage of covalent bonds. In addition, implications for teaching and future research are proposed.

  8. Incorporating Guided-Inquiry Learning into the Organic Chemistry Laboratory

    NASA Astrophysics Data System (ADS)

    Gaddis, Barbara A.; Schoffstall, Allen M.

    2007-05-01

    Informed science educators who are responsible for undergraduate laboratory programs strive to improve the effectiveness of learning in the laboratory. Guided-inquiry learning in the laboratory is one reasonable alternative (among others described here) to the verification approach to learning. Guided-inquiry learning offers students the opportunity to learn for themselves in a controlled laboratory environment where the instructor can handle the outcome and help guide students who are experiencing difficulty. Guided-inquiry experiments in organic chemistry have merit because they may help to improve understanding while increasing student interest. This paper presents the advantages and disadvantages of guided-inquiry experiments in organic chemistry. Several different types of guided-inquiry experiments in organic chemistry are summarized, together with the rationale for converting verification laboratory procedures to guided-inquiry experiments. Examples are given for enhancing guided-inquiry experiments to make the outcomes less predictable.

  9. Organic chemistry on Titan: Surface interactions

    NASA Technical Reports Server (NTRS)

    Thompson, W. Reid; Sagan, Carl

    1992-01-01

    The interaction of Titan's organic sediments with the surface (solubility in nonpolar fluids) is discussed. How Titan's sediments can be exposed to an aqueous medium for short, but perhaps significant, periods of time is also discussed. Interactions with hydrocarbons and with volcanic magmas are considered. The alteration of Titan's organic sediments over geologic time by the impacts of meteorites and comets is discussed.

  10. "Drug" Discovery with the Help of Organic Chemistry.

    PubMed

    Itoh, Yukihiro; Suzuki, Takayoshi

    2017-01-01

     The first step in "drug" discovery is to find compounds binding to a potential drug target. In modern medicinal chemistry, the screening of a chemical library, structure-based drug design, and ligand-based drug design, or a combination of these methods, are generally used for identifying the desired compounds. However, they do not necessarily lead to success and there is no infallible method for drug discovery. Therefore, it is important to explore medicinal chemistry based on not only the conventional methods but also new ideas. So far, we have found various compounds as drug candidates. In these studies, some strategies based on organic chemistry have allowed us to find drug candidates, through 1) construction of a focused library using organic reactions and 2) rational design of enzyme inhibitors based on chemical reactions catalyzed by the target enzyme. Medicinal chemistry based on organic chemical reactions could be expected to supplement the conventional methods. In this review, we present drug discovery with the help of organic chemistry showing examples of our explorative studies on histone deacetylase inhibitors and lysine-specific demethylase 1 inhibitors.

  11. View from My Classroom: Introductory Organic Chemistry with Instrumental Analysis: A Third Year High School Chemistry Course.

    ERIC Educational Resources Information Center

    Liebermann, John, Jr.

    1985-01-01

    Describes an advanced high school chemistry course that exposes students to a wide variety of modern, realistic instrumental techniques. The laboratory syllabus for the course (which uses the textbook "Organic Chemistry" by Morrison and Boyd) is included. (JN)

  12. Organic chemistry. Strain-release amination.

    PubMed

    Gianatassio, Ryan; Lopchuk, Justin M; Wang, Jie; Pan, Chung-Mao; Malins, Lara R; Prieto, Liher; Brandt, Thomas A; Collins, Michael R; Gallego, Gary M; Sach, Neal W; Spangler, Jillian E; Zhu, Huichin; Zhu, Jinjiang; Baran, Phil S

    2016-01-15

    To optimize drug candidates, modern medicinal chemists are increasingly turning to an unconventional structural motif: small, strained ring systems. However, the difficulty of introducing substituents such as bicyclo[1.1.1]pentanes, azetidines, or cyclobutanes often outweighs the challenge of synthesizing the parent scaffold itself. Thus, there is an urgent need for general methods to rapidly and directly append such groups onto core scaffolds. Here we report a general strategy to harness the embedded potential energy of effectively spring-loaded C-C and C-N bonds with the most oft-encountered nucleophiles in pharmaceutical chemistry, amines. Strain-release amination can diversify a range of substrates with a multitude of desirable bioisosteres at both the early and late stages of a synthesis. The technique has also been applied to peptide labeling and bioconjugation.

  13. The Organic Chemistry of Conducting Polymers

    SciTech Connect

    Tolbert, Laren Malcolm

    2014-12-01

    For the last several years, we have examined the fundamental principles of conduction in one-dimensional systems, i.e., molecular “wires”. It is, of course, widely recognized that such systems, as components of electronically conductive materials, function in a two- and three-dimensional milieu. Thus interchain hopping and grain-boundary resistivity are limiting conductivity factors in highly conductive materials, and overall conductivity is a function of through-chain and boundary hopping. We have given considerable attention to the basic principles underlying charge transport (the “rules of the game”) in two-dimensional systems by using model systems which allow direct observation of such processes, including the examination of tunneling and hopping as components of charge transfer. In related work, we have spent considerable effort on the chemistry of conjugated heteropolymers, most especially polythiophens, with the aim of using these most efficient of readily available electroactive polymers in photovoltaic devices.

  14. The Critical Role of Organic Chemistry in Drug Discovery.

    PubMed

    Rotella, David P

    2016-10-19

    Small molecules remain the backbone for modern drug discovery. They are conceived and synthesized by medicinal chemists, many of whom were originally trained as organic chemists. Support from government and industry to provide training and personnel for continued development of this critical skill set has been declining for many years. This Viewpoint highlights the value of organic chemistry and organic medicinal chemists in the complex journey of drug discovery as a reminder that basic science support must be restored.

  15. Organic chemistry: No double bond left behind

    NASA Astrophysics Data System (ADS)

    Sarlah, David

    2016-03-01

    Alkenyl halides are some of the most useful building blocks for synthesizing small organic molecules. A catalyst has now allowed their direct preparation from widely available alkenes using the cross-metathesis reaction. See Article p.459

  16. Predicted versus Actual Performance in Undergraduate Organic Chemistry and Implications for Student Advising

    ERIC Educational Resources Information Center

    Pursell, David P.

    2007-01-01

    Performance as measured by grades in the first and second semesters of organic chemistry was predicted using pre-college measures (SAT scores, high school rank, validation exams) and college measures (general chemistry GPA, overall college GPA prior to beginning organic chemistry, first-semester organic chemistry GPA). Data indicate that overall…

  17. Teaching Introductory Organic Chemistry: 'Blooming' beyond a Simple Taxonomy

    NASA Astrophysics Data System (ADS)

    Pungente, Michael D.; Badger, Rodney A.

    2003-07-01

    Undergraduate students often experience fear and trepidation when studying introductory organic chemistry: the majority of these students use a memorization approach to the material, sacrificing understanding. This paper describes one way the problem can be resolved. The cognitive working level we emphasize in our teaching practice involves making the necessary connections between the general chemistry principles that students have learned (or at least have been exposed to in their senior high school years and have revisited again in their university freshman year) and the many reactions and mechanisms they will encounter in organic chemistry. Educating students early in the course about the various levels of the cognitive process and the necessary working level of cognition for success in organic chemistry teaches connections between the general chemistry principles and reaction mechanisms. This empowers students to approach the subject from a perspective of understanding rather than memorization, and replaces fear and trepidation with confidence. In addition, this can help narrow the gap between what instructors expect from their students and what their students think is sufficient to master the course content.

  18. A Statistical Evaluation: Peer-led Team Learning in an Organic Chemistry Course.

    ERIC Educational Resources Information Center

    Lyle, Kenneth S.; Robinson, William R.

    2003-01-01

    Reports the status of peer-led learning, also known as Workshop Chemistry. This National Science Foundation (NSF) systemic-reform initiative focuses on general chemistry, organic chemistry, and biochemistry. (DDR)

  19. Oxidation and Reduction Reactions in Organic Chemistry

    ERIC Educational Resources Information Center

    Shibley, Ivan A., Jr.; Amaral, Katie E.; Aurentz, David J.; McCaully, Ronald J.

    2010-01-01

    A variety of approaches to the concept of oxidation and reduction appear in organic textbooks. The method proposed here is different than most published approaches. The oxidation state is calculated by totaling the number of heterogeneous atoms, [pi]-bonds, and rings. A comparison of the oxidation states of reactant and product determine what type…

  20. Carbohydrates as synthetic tools in organic chemistry.

    PubMed

    Boysen, Mike M K

    2007-01-01

    While amino acids, terpenes and alkaloids have found broad application as tools in stereoselective organic synthesis, carbohydrates have only lately been recognised as versatile starting materials for chiral auxiliaries, reagents, ligands and organocatalysts. The structural diversity of carbohydrates and the high density of functional groups offer a wide variety of opportunities for derivatization and tailoring of synthetic tools to a specific problem.

  1. Medical Mycology and the Chemistry Classroom: Germinating Student Interest in Organic Chemistry

    ERIC Educational Resources Information Center

    Bliss, Joseph M.; Reid, Christopher W.

    2013-01-01

    Efforts to provide active research context to introductory courses in basic sciences are likely to better engage learners and provide a framework for relevant concepts. A simple teaching and learning experiment was conducted to use concepts in organic chemistry to solve problems in the life sciences. Bryant University is a liberal arts university…

  2. Alternative Conceptions of Organic Chemistry Topics among Fourth Year Chemistry Students

    ERIC Educational Resources Information Center

    Rushton, Gregory T.; Hardy, Rebecca C.; Gwaltney, Kevin P.; Lewis, Scott E.

    2008-01-01

    This study describes the conceptual understanding for a series of fundamental organic concepts by fourth year chemistry students from a midsize, southeastern, state university. Student volunteers (n = 19) participated in semi-structured interviews using a think aloud protocol. The interview questions were eleven multiple choice questions selected…

  3. Implementing a Student-Designed Green Chemistry Laboratory Project in Organic Chemistry

    ERIC Educational Resources Information Center

    Graham, Kate J.; Jones, T. Nicholas; Schaller, Chris P.; McIntee, Edward J.

    2014-01-01

    A multiweek organic chemistry laboratory project is described that emphasizes sustainable practices in experimental design. An emphasis on student-driven development of the project is meant to mirror the independent nature of research. Students propose environmentally friendly modifications of several reactions. With instructor feedback, students…

  4. Student Response to a Partial Inversion of an Organic Chemistry Course for Non-Chemistry Majors

    ERIC Educational Resources Information Center

    Rein, Kathleen S.; Brookes, David T.

    2015-01-01

    We report the student response to a two-year transformation of a one-semester organic chemistry course for nonchemistry majors. The transformed course adopted a peer led team learning approach and incorporated case studies. Student attitudes toward the course transformation were assessed throughout the semester, and adjustments to the methods were…

  5. Piaget and Organic Chemistry: Teaching Introductory Organic Chemistry through Learning Cycles

    NASA Astrophysics Data System (ADS)

    Libby, R. Daniel

    1995-07-01

    This paper describes the first application of the Piaget-based learning cycle technique (Atkin & Karplus, Sci. Teach. 1962, 29, 45-51) to an introductory organic chemistry course. It also presents the step-by-step process used to convert a lecture course into a discussion-based active learning course. The course is taught in a series of learning cycles. A learning cycle is a three phase process that provides opportunities for students to explore new material and work with an instructor to recognize logical patterns in data, and devise and test hypotheses. In this application, the first phase, exploration, involves out-of-class student evaluation of data in attempts to identify significant trends and develop hypotheses that might explain the trends in terms of fundamental scientific principles. In the second phase, concept invention, the students and instructor work together in-class to evaluate student hypotheses and find concepts that work best in explaining the data. The third phase, application, is an out-of-class application of the concept to new situations. The development of learning cycles from lecture notes is presented as an 8 step procedure. The process involves revaluation and restructuring of the course material to maintain a continuity of concept development according to the instructor's logic, dividing topics into individual concepts or techniques, and refocusing the presentation in terms of large numbers of examples that can serve as data for students in their exploration and application activities. A sample learning cycle and suggestions for ways of limited implementation of learning cycles into existing courses are also provided.

  6. Telling It like It Is: Teaching Mechanisms in Organic Chemistry

    ERIC Educational Resources Information Center

    Ault, Addison

    2010-01-01

    In this article I support and extend the ideas presented by J. Brent Friesen in his article "Saying What You Mean; Teaching Mechanisms in Organic Chemistry" ("JCE" November, 2008). I emphasize "telling the truth" about proton transfers. The truth is that in aqueous acid most reactions are subject to "specific" acid catalysis: the only kinetically…

  7. A Simple Mnemonic for Tautomerization Mechanisms in Organic Chemistry

    ERIC Educational Resources Information Center

    Stephens, Chad E.

    2010-01-01

    The familiar word OREO (as in the cookie) is presented as a simple mnemonic for remembering the basic steps of the classical tautomerization mechanisms in organic chemistry. For acid-catalyzed tautomerizations, OREO stands for proton on, resonance, proton off. For base-catalyzed tautomerizations, OREO stands for proton off, resonance, proton on.…

  8. Integrating Symmetry in Stereochemical Analysis in Introductory Organic Chemistry

    ERIC Educational Resources Information Center

    Taagepera, Mare; Arasasingham, Ramesh D.; King, Susan; Potter, Frank; Martorell, Ingrid; Ford, David; Wu, Jason; Kearney, Aaron M.

    2011-01-01

    We report a comparative study using "knowledge space theory" (KAT) to assess the impact of a hands-on laboratory exercise that used molecular model kits to emphasize the connections between a plane of symmetry, Charity, and isomerism in an introductory organic chemistry course. The experimental design compared three groups of…

  9. Biodiesel Synthesis and Evaluation: An Organic Chemistry Experiment

    ERIC Educational Resources Information Center

    Bucholtz, Ehren C.

    2007-01-01

    A new lab esterification reaction based on biodiesel preparation and viscosity, which provides a model experience of industrial process to understand oxidation of vicinal alcohols by periodic acid, is presented. This new desertification experiment and periodate analysis of glycerol for the introductory organic chemistry laboratory provides an…

  10. Provocative Opinion: The Undergraduate Curriculum in Organic Chemistry.

    ERIC Educational Resources Information Center

    Wheeler, Desmond M. S.; Wheeler, Margaret M.

    1979-01-01

    The authors provide criticisms of the teaching of organic chemistry in the United States. They suggest that changes be made in the method of presentation of the material, with topics introduced early in the course providing framework for subsequent material. (Author/SA)

  11. Radical Recombination Kinetics: An Experiment in Physical Organic Chemistry.

    ERIC Educational Resources Information Center

    Pickering, Miles

    1980-01-01

    Describes a student kinetic experiment involving second order kinetics as well as displaying photochromism using a wide variety of techniques from both physical and organic chemistry. Describes measurement of (1) the rate of the recombination reaction; (2) the extinction coefficient; and (3) the ESR spectrometer signal. (Author/JN)

  12. An Organic Chemistry Experiment for Forensic Science Majors.

    ERIC Educational Resources Information Center

    Rothchild, Robert

    1979-01-01

    The laboratory experiment described here is intended to be of use to the forensic science major enrolled in a course in organic chemistry. The experiment is the use of thin-layer chromotography for qualitative analysis, specifically for the identification of drugs. (Author/SA)

  13. Synthesis of Bisphenol Z: An Organic Chemistry Experiment

    ERIC Educational Resources Information Center

    Gregor, Richard W.

    2012-01-01

    A student achievable synthesis of bisphenol Z, 4,4'-(cyclohexane-1,1-diyl)diphenol, from the acid-catalyzed reaction of phenol with cyclohexanone is presented. The experiment exemplifies all the usual pedagogy for the standard topic of electrophilic aromatic substitution present in the undergraduate organic chemistry curriculum, while providing…

  14. Sudoku Puzzles for First-Year Organic Chemistry Students

    ERIC Educational Resources Information Center

    Perez, Alice L.; Lamoureux, G.

    2007-01-01

    Sudoku puzzle was designed to teach about amino acids and functional groups to the students of undergraduate organic chemistry students. The puzzles focus on helping the student learn the name, 3-letter code and 1-letter code of common amino acids and functional groups.

  15. A Process Model for the Comprehension of Organic Chemistry Notation

    ERIC Educational Resources Information Center

    Havanki, Katherine L.

    2012-01-01

    This dissertation examines the cognitive processes individuals use when reading organic chemistry equations and factors that affect these processes, namely, visual complexity of chemical equations and participant characteristics (expertise, spatial ability, and working memory capacity). A six stage process model for the comprehension of organic…

  16. Promoting Representational Competence with Molecular Models in Organic Chemistry

    ERIC Educational Resources Information Center

    Stull, Andrew T.; Gainer, Morgan; Padalkar, Shamin; Hegarty, Mary

    2016-01-01

    Mastering the many different diagrammatic representations of molecules used in organic chemistry is challenging for students. This article summarizes recent research showing that manipulating 3-D molecular models can facilitate the understanding and use of these representations. Results indicate that students are more successful in translating…

  17. Patterns in Organometallic Chemistry with Application in Organic Synthesis.

    ERIC Educational Resources Information Center

    Schwartz, Jeffrey; Labinger, Jay A.

    1980-01-01

    Of interest in this discussion of organometallic complexes are stoichiometric or catalytic reagents for organic synthesis in the complex transformations observed during synthesis for transition metal organometallic complexes. Detailed are general reaction types from which the chemistry or many transition metal organometallic complexes can be…

  18. Biodiesel from Seeds: An Experiment for Organic Chemistry

    ERIC Educational Resources Information Center

    Goldstein, Steven W.

    2014-01-01

    Plants can store the chemical energy required by their developing offspring in the form of triglycerides. These lipids can be isolated from seeds and then converted into biodiesel through a transesterification reaction. This second-year undergraduate organic chemistry laboratory experiment exemplifies the conversion of an agricultural energy…

  19. The Role of Spatial Ability and Achievement in Organic Chemistry.

    ERIC Educational Resources Information Center

    Pribyl, Jeffrey R.; Bodner, George M.

    This study investigated the role that spatial ability has in achievement in organic chemistry. Spatial ability was defined as containing two subfactors--spatial visualization and spatial orientation. Spatial visualization is the ability to mentally manipulate pictorially presented stimuli; involved in the processes of manipulation are the…

  20. Learning Organic Chemistry through a Study of Semiochemicals

    ERIC Educational Resources Information Center

    Pernaa, Johannes; Aksela, Maija

    2011-01-01

    The topics of nature, for example semiochemicals, are motivating topics, which can be used to teach organic chemistry at high school level. The history, classifications, a few important applications of semiochemicals, and an semiochemical that can be synthesized in the laboratory are presented. The laboratory synthesis is carried out through the…

  1. How Do Organic Chemistry Students Understand and Apply Hydrogen Bonding?

    ERIC Educational Resources Information Center

    Henderleiter, J.; Smart, R.; Anderson, J.; Elian, O.

    2001-01-01

    Examines how students completing a two-semester organic sequence understand, explain, and apply hydrogen bonding to determine the physical attributes of molecules. Suggests that some students completing what is typically their second year of college-level chemistry still possess misconceptions about hydrogen bonds. (Contains 21 references.) (ASK)

  2. Omar Yaghi on Chemistry and Metal Organic Frameworks

    SciTech Connect

    Omar Yaghi

    2012-07-23

    In this edited version of the hour long talk, Omar Yaghi, director of the Molecular Foundry, sat down in conversation with Jeff Miller, head of Public Affairs, on July 11th, 2012 to discuss his fascination with the hidden world of chemistry and his work on Metal Organic Frameworks.

  3. Toward Consistent Terminology for Cyclohexane Conformers in Introductory Organic Chemistry

    ERIC Educational Resources Information Center

    Nelson, Donna J.; Brammer, Christopher N.

    2011-01-01

    Recommended changes in use of cyclohexane conformers and their nomenclature will remedy inconsistencies in cyclohexane conformers and their nomenclature that exist across currently used organic chemistry textbooks. These inconsistencies prompted this logical analysis and the resulting recommendations. Recommended conformer names are "chair",…

  4. Omar Yaghi on Chemistry and Metal Organic Frameworks

    ScienceCinema

    Omar Yaghi

    2016-07-12

    In this edited version of the hour long talk, Omar Yaghi, director of the Molecular Foundry, sat down in conversation with Jeff Miller, head of Public Affairs, on July 11th, 2012 to discuss his fascination with the hidden world of chemistry and his work on Metal Organic Frameworks.

  5. Using Ozone in Organic Chemistry Lab: The Ozonolysis of Eugenol

    ERIC Educational Resources Information Center

    Branan, Bruce M.; Butcher, Joshua T.; Olsen, Lawrence R.

    2007-01-01

    An ozonolysis experiment, suitable for undergraduate organic chemistry lab, is presented. Ozonolysis of eugenol (clove oil), followed by reductive workup furnishes an aldehyde that is easily identified by its NMR and IR spectra. Ozone (3-5% in oxygen) is produced using an easily built generator. (Contains 2 figures and 1 scheme.)

  6. Organic chemistry meets polymers, nanoscience, therapeutics and diagnostics.

    PubMed

    Rotello, Vincent M

    2016-01-01

    The atom-by-atom control provided by synthetic organic chemistry presents a means of generating new functional nanomaterials with great precision. Bringing together these two very disparate skill sets is, however, quite uncommon. This autobiographical review provides some insight into how my program evolved, as well as giving some idea of where we are going.

  7. Organic chemistry meets polymers, nanoscience, therapeutics and diagnostics

    PubMed Central

    2016-01-01

    Summary The atom-by-atom control provided by synthetic organic chemistry presents a means of generating new functional nanomaterials with great precision. Bringing together these two very disparate skill sets is, however, quite uncommon. This autobiographical review provides some insight into how my program evolved, as well as giving some idea of where we are going. PMID:27559417

  8. Does Mechanistic Thinking Improve Student Success in Organic Chemistry?

    ERIC Educational Resources Information Center

    Grove, Nathaniel P.; Cooper, Melanie M.; Cox, Elizabeth L.

    2012-01-01

    The use of the curved-arrow notation to depict electron flow during mechanistic processes is one of the most important representational conventions in the organic chemistry curriculum. Our previous research documented a disturbing trend: when asked to predict the products of a series of reactions, many students do not spontaneously engage in…

  9. Synthesis and Chemistry of Organic Geminal Di- and Triazides.

    PubMed

    Häring, Andreas P; Kirsch, Stefan F

    2015-11-06

    This review recapitulates all available literature dealing with the synthesis and reactivity of geminal organic di- and triazides. These compound classes are, to a large extent, unexplored despite their promising chemical properties and their simple preparation. In addition, the chemistry of carbonyl diazide (2) and tetraazidomethane (105) is described in separate sections.

  10. Interstellar grain chemistry and organic molecules

    NASA Technical Reports Server (NTRS)

    Allamandola, L. J.; Sandford, S. A.

    1990-01-01

    The detection of prominant infrared absorption bands at 3250, 2170, 2138, 1670 and 1470 cm(-1) (3.08, 4.61, 4.677, 5.99 and 6.80 micron m) associated with molecular clouds show that mixed molecular (icy) grain mantles are an important component of the interstellar dust in the dense interstellar medium. These ices, which contain many organic molecules, may also be the production site of the more complex organic grain mantles detected in the diffuse interstellar medium. Theoretical calculations employing gas phase as well as grain surface reactions predict that the ices should be dominated only by the simple molecules H2O, H2CO, N2, CO, O2, NH3, CH4, possibly CH3OH, and their deuterated counterparts. However, spectroscopic observations in the 2500 to 1250 cm(-1)(4 to 8 micron m) range show substantial variation from source reactions alone. By comparing these astronomical spectra with the spectra of laboratory-produced analogs of interstellar ices, one can determine the composition and abundance of the materials frozen on the grains in dense clouds. Experiments are described in which the chemical evolution of an interstellar ice analog is determined during irradiation and subsequent warm-up. Particular attention is paid to the types of moderately complex organic materials produced during these experiments which are likely to be present in interstellar grains and cometary ices.

  11. Academia-industry symbiosis in organic chemistry.

    PubMed

    Michaudel, Quentin; Ishihara, Yoshihiro; Baran, Phil S

    2015-03-17

    Collaboration between academia and industry is a growing phenomenon within the chemistry community. These sectors have long held strong ties since academia traditionally trains the future scientists of the corporate world, but the recent drastic decrease of public funding is motivating the academic world to seek more private grants. This concept of industrial "sponsoring" is not new, and in the past, some companies granted substantial amounts of money per annum to various academic institutions in exchange for prime access to all their scientific discoveries and inventions. However, academic and industrial interests were not always aligned, and therefore the investment has become increasingly difficult to justify from industry's point of view. With fluctuating macroeconomic factors, this type of unrestricted grant has become more rare and has been largely replaced by smaller and more focused partnerships. In our view, forging a partnership with industry can be a golden opportunity for both parties and can represent a true symbiosis. This type of project-specific collaboration is engendered by industry's desire to access very specific academic expertise that is required for the development of new technologies at the forefront of science. Since financial pressures do not allow companies to spend the time to acquire this expertise and even less to explore fundamental research, partnering with an academic laboratory whose research is related to the problem gives them a viable alternative. From an academic standpoint, it represents the perfect occasion to apply "pure science" research concepts to solve problems that benefit humanity. Moreover, it offers a unique opportunity for students to face challenges from the "real world" at an early stage of their career. Although not every problem in industry can be solved by research developments in academia, we argue that there is significant scientific overlap between these two seemingly disparate groups, thereby presenting an

  12. Academia–Industry Symbiosis in Organic Chemistry

    PubMed Central

    2015-01-01

    Conspectus Collaboration between academia and industry is a growing phenomenon within the chemistry community. These sectors have long held strong ties since academia traditionally trains the future scientists of the corporate world, but the recent drastic decrease of public funding is motivating the academic world to seek more private grants. This concept of industrial “sponsoring” is not new, and in the past, some companies granted substantial amounts of money per annum to various academic institutions in exchange for prime access to all their scientific discoveries and inventions. However, academic and industrial interests were not always aligned, and therefore the investment has become increasingly difficult to justify from industry’s point of view. With fluctuating macroeconomic factors, this type of unrestricted grant has become more rare and has been largely replaced by smaller and more focused partnerships. In our view, forging a partnership with industry can be a golden opportunity for both parties and can represent a true symbiosis. This type of project-specific collaboration is engendered by industry’s desire to access very specific academic expertise that is required for the development of new technologies at the forefront of science. Since financial pressures do not allow companies to spend the time to acquire this expertise and even less to explore fundamental research, partnering with an academic laboratory whose research is related to the problem gives them a viable alternative. From an academic standpoint, it represents the perfect occasion to apply “pure science” research concepts to solve problems that benefit humanity. Moreover, it offers a unique opportunity for students to face challenges from the “real world” at an early stage of their career. Although not every problem in industry can be solved by research developments in academia, we argue that there is significant scientific overlap between these two seemingly disparate

  13. Science: Introduction to Chemistry, Organic Chemistry, Qualitative Analysis, Introduction to Biochemistry. Authorized Course of Instruction for the Quinmester Program.

    ERIC Educational Resources Information Center

    Dade County Public Schools, Miami, FL.

    Performance objectives are stated for each of the secondary school units included in this package of instructional guides prepared for the Dade County Florida Quinmester Program. All four units are concerned with chemistry: "Introduction of Chemistry,""Organic Chemistry,""Qualitative Analysis," and "Introduction…

  14. Organic N-chloramines: chemistry and toxicology.

    PubMed

    Scully, F E; Bempong, M A

    1982-12-01

    The stability of aqueous solutions of organic N-chloramines, suspected of contaminating chlorinated water, has been studied. Two factors influence the decomposition of solutions of N-chloropiperidine and N-chlorodiethylamine: a spontaneous decomposition and photodecomposition. Since solutions of these compounds are relatively long-lived, a need for an analytical method for their identification is discussed. A new method is described which involves reaction of organic N-chloramines with arenesulfinic acid salts. The method gives high yields of stable arenesulfonamides. Several toxicological studies of N-chloropiperidine are described. The compound is mutagenic by Ames assay in Salmonella typhimurium strain TA 100 and does not require metabolic activation as indicated in a total body fluids analysis using C57BL/J6 mice. N-Chloropiperidine was subjected to a modified in vitro cell transformation assay using diploid fibroblast cells from Syrian hamster fetuses. A maximum number of foci of 4 per dish was observed at a seeding of 5 X 10(3) cells/60 mm dish. Under similar conditions, MNNG-induced foci ranged from 4 to 7 per dish.

  15. Planetary organic chemistry and the origins of biomolecules.

    PubMed

    Benner, Steven A; Kim, Hyo-Joong; Kim, Myung-Jung; Ricardo, Alonso

    2010-07-01

    Organic chemistry on a planetary scale is likely to have transformed carbon dioxide and reduced carbon species delivered to an accreting Earth. According to various models for the origin of life on Earth, biological molecules that jump-started Darwinian evolution arose via this planetary chemistry. The grandest of these models assumes that ribonucleic acid (RNA) arose prebiotically, together with components for compartments that held it and a primitive metabolism that nourished it. Unfortunately, it has been challenging to identify possible prebiotic chemistry that might have created RNA. Organic molecules, given energy, have a well-known propensity to form multiple products, sometimes referred to collectively as "tar" or "tholin." These mixtures appear to be unsuited to support Darwinian processes, and certainly have never been observed to spontaneously yield a homochiral genetic polymer. To date, proposed solutions to this challenge either involve too much direct human intervention to satisfy many in the community, or generate molecules that are unreactive "dead ends" under standard conditions of temperature and pressure. Carbohydrates, organic species having carbon, hydrogen, and oxygen atoms in a ratio of 1:2:1 and an aldehyde or ketone group, conspicuously embody this challenge. They are components of RNA and their reactivity can support both interesting spontaneous chemistry as part of a "carbohydrate world," but they also easily form mixtures, polymers and tars. We describe here the latest thoughts on how on this challenge, focusing on how it might be resolved using minerals containing borate, silicate, and molybdate, inter alia.

  16. Carbinolamines and Geminal Diols in Aqueous Environmental Organic Chemistry

    NASA Astrophysics Data System (ADS)

    Urbansky, Edward T.

    2000-12-01

    Organic chemistry textbooks generally treat geminal diols as curiosities--exceptions to the stability of the C=O double bond. However, most aldehydes of environmental significance, to wit, trichloroethanal (chloral), methanal (formaldehyde), ethanal (acetaldehyde), and propanal (propionaldehyde), exhibit this behavior. Carbinolamines (hemiaminals) are usually considered to be unstable reaction intermediates of very short lifetime, despite a considerable volume of literature that suggests otherwise. In aqueous solution, carbinolamines can build up to substantial concentrations and play important roles in kinetics of aldehyde reactions, subsequent to formation of aldehydes as ozonation by-products during drinking water disinfection. A few carbinolamines are isolable, although these are not encountered in environmental systems. In general, the minimal conceptual treatment of these chemical species results from the central theme of synthetic utility that quite reasonably dominates organic chemistry courses and textbooks. Nonetheless, a pedagogical consequence is that students may be left with an incorrect perception that these species are unlikely to be encountered in common situations. Accordingly, it is important for teachers and students of environmental chemistry to remember that aqueous chemistry can be quite different from that observed in less polar and sometimes aprotic organic solvents.

  17. New organic chemistry of sulfur dioxide.

    PubMed

    Vogel, Pierre; Turks, Maris; Bouchez, Laure; Marković, Dean; Varela-Alvarez, Adrián; Sordo, José Angel

    2007-10-01

    Simple 1,3-dienes undergo highly stereoselective hetero-Diels-Alder additions with SO2 at low temperature giving sultines. These reactions that are faster than the more exothermic cheletropic additions of SO2-producing sulfolenes. This has led to the invention of a new C-C bond-forming reaction combining electron-rich dienes and alkenes with SO2. The reaction cascade has been exploited to develop combinatorial, one-pot, four-component syntheses of polyfunctional sulfones, sulfonamides, and sulfonic esters. It also allows us to generate, in one-pot operations, enantiomerically enriched polypropionate fragments containing up to three contiguous stereogenic centers and a (E)-alkene unit. These fragments can be used directly in further C-C bond-forming reactions, such as cross-aldol condensations, thus permitting the expeditious construction of complicated natural products of biological interest (e.g., Baconipyrones, Rifamycin S, Apoptolidinone) and analogues. New ene reactions of SO2 have also been discovered; they open new avenues to organic synthesis.

  18. Infusing the Chemistry Curriculum with Green Chemistry Using Real-World Examples, Web Modules, and Atom Economy in Organic Chemistry Courses

    ERIC Educational Resources Information Center

    Cann, Michael C.; Dickneider, Trudy A.

    2004-01-01

    Green chemistry is the awareness of the damaging environmental effects due to chemical research and inventions. There is emphasis on a need to include green chemistry in synthesis with atom economy in organic chemistry curriculum to ensure an environmentally conscious future generation of chemists, policy makers, health professionals and business…

  19. Soap from Nutmeg: An Integrated Introductory Organic Chemistry Laboratory Experiment

    NASA Astrophysics Data System (ADS)

    de Mattos, Marcio C. S.; Nicodem, David E.

    2002-01-01

    The extraction of trimyristin from nutmeg, its purification, and its conversion to a soap (sodium myristate) are described. Concepts such as the isolation of a natural product, recrystallization, identification of a solid, solubility, acidity and basicity, and organic reaction can be presented to students using integrated experiments in an introductory experimental chemistry laboratory. These experiments can easily be done in three class periods of four hours.

    See Letter re: this article.

  20. Organic Chemistry Self Instructional Package 7: Alkenes-Nomenclature and Isomerism.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  1. Organic Chemistry Self Instructional Package 3: Alkanes-Homologous Series and Isomerism.

    ERIC Educational Resources Information Center

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  2. Organic Chemistry Educators' Perspectives on Fundamental Concepts and Misconceptions: An Exploratory Study

    ERIC Educational Resources Information Center

    Duis, Jennifer M.

    2011-01-01

    An exploratory study was conducted with 23 organic chemistry educators to discover what general chemistry concepts they typically review, the concepts they believe are fundamental to introductory organic chemistry, the topics students find most difficult in the subject, and the misconceptions they observe in undergraduate organic chemistry…

  3. Mixed-Methods Study of Online and Written Organic Chemistry Homework

    ERIC Educational Resources Information Center

    Malik, Kinza; Martinez, Nylvia; Romero, Juan; Schubel, Skyler; Janowicz, Philip A.

    2014-01-01

    Connect for organic chemistry is an online learning tool that gives students the opportunity to learn about all aspects of organic chemistry through the ease of the digital world. This research project consisted of two fundamental questions. The first was to discover whether there was a difference in undergraduate organic chemistry content…

  4. A Forty Year Odyssey in Metallo-Organic Chemistry.

    PubMed

    Nicholas, Kenneth M

    2015-07-17

    In this invited Perspective, I provide a personal account highlighting several of my group's research contributions in metallo-organic chemistry over the past 40 years. Our early work focused primarily in stoichiometric structure/reactivity of transition metal-organic compounds and their use in organic synthesis. More recent efforts have centered on the discovery and development of new metal-catalyzed organic reactions via reactive metal-organic intermediates. The major research findings that are described here include (1) propargyl-cobalt complexes as electrophilic agents for C-C and C-Nu coupling; (2) the activation of carbon dioxide by metal complexes; (3) metal-promoted C-H nitrogenation reactions; (4) oxo-metal catalyzed deoxygenation reactions; and (5) catalyst discovery via dynamic templating with substrate- and transition-state analogues.

  5. Planetary Organic Chemistry and the Origins of Biomolecules

    PubMed Central

    Benner, Steven A.; Kim, Hyo-Joong; Kim, Myung-Jung; Ricardo, Alonso

    2010-01-01

    Organic chemistry on a planetary scale is likely to have transformed carbon dioxide and reduced carbon species delivered to an accreting Earth. According to various models for the origin of life on Earth, biological molecules that jump-started Darwinian evolution arose via this planetary chemistry. The grandest of these models assumes that ribonucleic acid (RNA) arose prebiotically, together with components for compartments that held it and a primitive metabolism that nourished it. Unfortunately, it has been challenging to identify possible prebiotic chemistry that might have created RNA. Organic molecules, given energy, have a well-known propensity to form multiple products, sometimes referred to collectively as “tar” or “tholin.” These mixtures appear to be unsuited to support Darwinian processes, and certainly have never been observed to spontaneously yield a homochiral genetic polymer. To date, proposed solutions to this challenge either involve too much direct human intervention to satisfy many in the community, or generate molecules that are unreactive “dead ends” under standard conditions of temperature and pressure. Carbohydrates, organic species having carbon, hydrogen, and oxygen atoms in a ratio of 1:2:1 and an aldehyde or ketone group, conspicuously embody this challenge. They are components of RNA and their reactivity can support both interesting spontaneous chemistry as part of a “carbohydrate world,” but they also easily form mixtures, polymers and tars. We describe here the latest thoughts on how on this challenge, focusing on how it might be resolved using minerals containing borate, silicate, and molybdate, inter alia. PMID:20504964

  6. MIANN models in medicinal, physical and organic chemistry.

    PubMed

    González-Díaz, Humberto; Arrasate, Sonia; Sotomayor, Nuria; Lete, Esther; Munteanu, Cristian R; Pazos, Alejandro; Besada-Porto, Lina; Ruso, Juan M

    2013-01-01

    Reducing costs in terms of time, animal sacrifice, and material resources with computational methods has become a promising goal in Medicinal, Biological, Physical and Organic Chemistry. There are many computational techniques that can be used in this sense. In any case, almost all these methods focus on few fundamental aspects including: type (1) methods to quantify the molecular structure, type (2) methods to link the structure with the biological activity, and others. In particular, MARCH-INSIDE (MI), acronym for Markov Chain Invariants for Networks Simulation and Design, is a well-known method for QSAR analysis useful in step (1). In addition, the bio-inspired Artificial-Intelligence (AI) algorithms called Artificial Neural Networks (ANNs) are among the most powerful type (2) methods. We can combine MI with ANNs in order to seek QSAR models, a strategy which is called herein MIANN (MI & ANN models). One of the first applications of the MIANN strategy was in the development of new QSAR models for drug discovery. MIANN strategy has been expanded to the QSAR study of proteins, protein-drug interactions, and protein-protein interaction networks. In this paper, we review for the first time many interesting aspects of the MIANN strategy including theoretical basis, implementation in web servers, and examples of applications in Medicinal and Biological chemistry. We also report new applications of the MIANN strategy in Medicinal chemistry and the first examples in Physical and Organic Chemistry, as well. In so doing, we developed new MIANN models for several self-assembly physicochemical properties of surfactants and large reaction networks in organic synthesis. In some of the new examples we also present experimental results which were not published up to date.

  7. Spectroscopic diagnostics of organic chemistry in the protostellar environment

    NASA Technical Reports Server (NTRS)

    Charnley, S. B.; Ehrenfreund, P.; Kuan, Y. J.

    2001-01-01

    A combination of astronomical observations, laboratory studies, and theoretical modelling is necessary to determine the organic chemistry of dense molecular clouds. We present spectroscopic evidence for the composition and evolution of organic molecules in protostellar environments. The principal reaction pathways to complex molecule formation by catalysis on dust grains and by reactions in the interstellar gas are described. Protostellar cores, where warming of dust has induced evaporation of icy grain mantles, are excellent sites in which to study the interaction between gas phase and grain-surface chemistries. We investigate the link between organics that are observed as direct products of grain surface reactions and those which are formed by secondary gas phase reactions of evaporated surface products. Theory predicts observable correlations between specific interstellar molecules, and also which new organics are viable for detection. We discuss recent infrared observations obtained with the Infrared Space Observatory, laboratory studies of organic molecules, theories of molecule formation, and summarise recent radioastronomical searches for various complex molecules such as ethers, azaheterocyclic compounds, and amino acids.

  8. Recent Discoveries and Future Challenges in Atmospheric Organic Chemistry.

    PubMed

    Glasius, Marianne; Goldstein, Allen H

    2016-03-15

    Earth's atmosphere contains a multitude of organic compounds, which differ by orders of magnitude regarding fundamental properties such as volatility, reactivity, and propensity to form cloud droplets, affecting their impact on global climate and human health. Despite recent major research efforts and advances, there are still substantial gaps in understanding of atmospheric organic chemistry, hampering efforts to understand, model, and mitigate environmental problems such as aerosol formation in both polluted urban and more pristine regions. The analytical toolbox available for chemists to study atmospheric organic components has expanded considerably during the past decade, opening new windows into speciation, time resolution and detection of reactive and semivolatile compounds at low concentrations. This has provided unprecedented opportunities, but also unveiled new scientific challenges. Specific groundbreaking examples include the role of epoxides in aerosol formation especially from isoprene, the importance of highly oxidized, reactive organics in air-surface processes (whether atmosphere-biosphere exchange or aerosols), as well as the extent of interactions of anthropogenic and biogenic emissions and the resulting impact on atmospheric organic chemistry.

  9. Provocative Opinion. Provocative Replies: Two Organic Chemists Look at Organic Chemistry Lab.

    ERIC Educational Resources Information Center

    Kandel, Marjorie; Ikan, Raphael

    1989-01-01

    Provides a point of view that the organic lab is a good place for the student to use and learn problem solving skills while performing the cookbook experiments. Notes that an equilibrium between the theoretical and practical aspects of organic chemistry should be established. (MVL)

  10. Organic chemistry. Nanomole-scale high-throughput chemistry for the synthesis of complex molecules.

    PubMed

    Buitrago Santanilla, Alexander; Regalado, Erik L; Pereira, Tony; Shevlin, Michael; Bateman, Kevin; Campeau, Louis-Charles; Schneeweis, Jonathan; Berritt, Simon; Shi, Zhi-Cai; Nantermet, Philippe; Liu, Yong; Helmy, Roy; Welch, Christopher J; Vachal, Petr; Davies, Ian W; Cernak, Tim; Dreher, Spencer D

    2015-01-02

    At the forefront of new synthetic endeavors, such as drug discovery or natural product synthesis, large quantities of material are rarely available and timelines are tight. A miniaturized automation platform enabling high-throughput experimentation for synthetic route scouting to identify conditions for preparative reaction scale-up would be a transformative advance. Because automated, miniaturized chemistry is difficult to carry out in the presence of solids or volatile organic solvents, most of the synthetic "toolkit" cannot be readily miniaturized. Using palladium-catalyzed cross-coupling reactions as a test case, we developed automation-friendly reactions to run in dimethyl sulfoxide at room temperature. This advance enabled us to couple the robotics used in biotechnology with emerging mass spectrometry-based high-throughput analysis techniques. More than 1500 chemistry experiments were carried out in less than a day, using as little as 0.02 milligrams of material per reaction.

  11. Molecular Images in Organic Chemistry: Assessment of Understanding in Aromaticity, Symmetry, Spectroscopy, and Shielding

    ERIC Educational Resources Information Center

    Ealy, Julie B.; Hermanson, Jim

    2006-01-01

    When students take General Chemistry there are substantially fewer molecular images than they will encounter in Organic Chemistry. The molecular images Organic Chemistry students see in their textbooks are ones that use dashes and wedges to represent 2D and semi 3D views, ball and spoke, ball and wire, and structural formulas, to name just a few.…

  12. Modules for Introducing Organometallic Reactions: A Bridge between Organic and Inorganic Chemistry

    ERIC Educational Resources Information Center

    Schaller, Chris P.; Graham, Kate J.; Johnson, Brian J.

    2015-01-01

    Transition metal organometallic reactions have become increasingly important in the synthesis of organic molecules. A new approach has been developed to introduce organometallic chemistry, along with organic and inorganic chemistry, at the foundational level. This change highlights applications of organometallic chemistry that have dramatically…

  13. The chemistry of cyborgs--interfacing technical devices with organisms.

    PubMed

    Giselbrecht, Stefan; Rapp, Bastian E; Niemeyer, Christof M

    2013-12-23

    The term "cyborg" refers to a cybernetic organism, which characterizes the chimera of a living organism and a machine. Owing to the widespread application of intracorporeal medical devices, cyborgs are no longer exclusively a subject of science fiction novels, but technically they already exist in our society. In this review, we briefly summarize the development of modern prosthetics and the evolution of brain-machine interfaces, and discuss the latest technical developments of implantable devices, in particular, biocompatible integrated electronics and microfluidics used for communication and control of living organisms. Recent examples of animal cyborgs and their relevance to fundamental and applied biomedical research and bioethics in this novel and exciting field at the crossroads of chemistry, biomedicine, and the engineering sciences are presented.

  14. Biocatalysis in organic chemistry and biotechnology: past, present, and future.

    PubMed

    Reetz, Manfred T

    2013-08-28

    Enzymes as catalysts in synthetic organic chemistry gained importance in the latter half of the 20th century, but nevertheless suffered from two major limitations. First, many enzymes were not accessible in large enough quantities for practical applications. The advent of recombinant DNA technology changed this dramatically in the late 1970s. Second, many enzymes showed a narrow substrate scope, often poor stereo- and/or regioselectivity and/or insufficient stability under operating conditions. With the development of directed evolution beginning in the 1990s and continuing to the present day, all of these problems can be addressed and generally solved. The present Perspective focuses on these and other developments which have popularized enzymes as part of the toolkit of synthetic organic chemists and biotechnologists. Included is a discussion of the scope and limitation of cascade reactions using enzyme mixtures in vitro and of metabolic engineering of pathways in cells as factories for the production of simple compounds such as biofuels and complex natural products. Future trends and problems are also highlighted, as is the discussion concerning biocatalysis versus nonbiological catalysis in synthetic organic chemistry. This Perspective does not constitute a comprehensive review, and therefore the author apologizes to those researchers whose work is not specifically treated here.

  15. Alkyl nitrate photochemistry during the tropospheric organic chemistry experiment

    NASA Astrophysics Data System (ADS)

    Worton, David R.; Reeves, Claire E.; Penkett, Stuart A.; Sturges, William T.; Slemr, Jana; Oram, David E.; Bandy, Brian J.; Bloss, William J.; Carslaw, Nicola; Davey, James; Emmerson, Kathryn M.; Gravestock, Thomas J.; Hamilton, Jacqueline F.; Heard, Dwayne E.; Hopkins, James R.; Hulse, Anne; Ingram, Trevor; Jacob, Mark J.; Lee, James D.; Leigh, Roland J.; Lewis, Alastair C.; Monks, Paul S.; Smith, Shona C.

    2010-02-01

    Alkyl nitrates (C 1-C 5) were measured at two sites (near urban and rural) in southeast England during the Tropospheric Organic Chemistry Experiment (TORCH). Methyl nitrate was the dominant species during both campaigns accounting for on average about one third of the total measured alkyl nitrates. High mixing ratios (>50 pptv) and variability of methyl nitrate were observed at the near urban site (TORCH1) that were not seen at the rural site (TORCH2) and which could not be explained by local photochemical production or direct emissions. The diurnal variation of methyl nitrate during TORCH1 showed a morning maximum that would be consistent with nighttime chemistry followed by transport to the surface by boundary layer dynamics. Similarly, elevated morning mixing ratios were also observed during TORCH2 although the magnitudes were much smaller. As a result, methyl nitrate could represent a tracer for nighttime chemistry seen at the ground the following day. At both campaigns, the dominant source of short chain alkyl nitrates and carbonyl precursor radicals (≤C 4) were from decomposition of larger compounds. The magnitude of the source increased with decreasing carbon number consistent with increasing total precursor abundance. Non-photochemical emissions of acetaldehyde and acetone could not be accounted for by automobile exhaust emissions alone and indicated that other direct sources are likely important in this environment.

  16. Gender Differences in Cognitive and Noncognitive Factors Related to Achievement in Organic Chemistry

    NASA Astrophysics Data System (ADS)

    Turner, Ronna C.; Lindsay, Harriet A.

    2003-05-01

    For many college students in the sciences, organic chemistry poses a difficult challenge. Indeed, success in organic chemistry has proven pivotal in the careers of a vast number of students in a variety of science disciplines. A better understanding of the factors that contribute to achievement in this course should contribute to efforts to increase the number of students in the science disciplines. Further, an awareness of gender differences in factors associated with achievement should aid efforts to bolster the participation of women in chemistry and related disciplines. Using a correlation research design, the individual relationships between organic chemistry achievement and each of several cognitive variables and noncognitive variables were assessed. In addition, the relationships between organic chemistry achievement and combinations of these independent variables were explored. Finally, gender- and instructor-related differences in the relationships between organic chemistry achievement and the independent variables were investigated. Cognitive variables included the second-semester general chemistry grade, the ACT English, math, reading, and science-reasoning scores, and scores from a spatial visualization test. Noncognitive variables included anxiety, confidence, effectance motivation, and usefulness. The second-semester general chemistry grade was found to be the best indicator of performance in organic chemistry, while the effectiveness of other predictors varied between instructors. In addition, gender differences were found in the explanations of organic chemistry achievement variance provided by this study. In general, males exhibited stronger correlations between predictor variables and organic chemistry achievement than females.

  17. Caring for the Environment While Teaching Organic Chemistry

    NASA Astrophysics Data System (ADS)

    Santos Santos, Elvira; Cruz Gavilan Garcia, Irma; Florencia Lejarazo Gomez, Eva

    2004-02-01

    In laboratory experiments it is common for students to acquire knowledge and develop the basic abilities needed to solve different types of problems related to synthesis and analysis. The students are so interested in this objective that they do not generally pay any attention to the wastes generated during their lab experiments. It is well known that experiments usually generate small quantities of a large variety of wastes. Nevertheless, the complexity of the wastes generated in the laboratories of educational institutions is large. Thus, detailed studies of their treatment should be undertaken. In North American and European universities the problem has been solved by sending these wastes to specialized companies that treat and dispose of them; however, in Mexico, such alternatives are not available owing to the high cost for waste disposal. Therefore, the Organic Chemistry Department of the Chemistry School at the National Autonomous University of Mexico has started a project concerned with the management and treatment of wastes generated during experimental lab sessions. In the United States and Europe, students do not generally treat their wastes. Therefore, it would be convenient to include this treatment as part of the educational aspects in organic experiments in all parts of the world to develop an environmentally conscience culture among them.

  18. Plasma deposition of organic thin films: Control of film chemistry

    SciTech Connect

    Ratner, B.D.

    1993-12-31

    Plasma deposition of thin, polymeric films represent a versatile surface modification technology. Although these thin films are exploited for many applications, complaints heard about plasma deposited films are that their structures are uncharacterizable, that organic functionality is lost in their production and that reproducibility is difficult. Recently, new methods for film production, reactor control and surface characterization have led to well characterized plasma deposited thin polymeric films (PDTPF) with defined structure and organic functionality. Such PDTPF often closely resemble conventionally prepared homopolymers. Methods that can be used to control the chemistry of PDTPF are the minimization of the plasma power, pulsing the RF field to reduce the {open_quotes}plasma on{close_quotes} time, use of a Faraday cage to reduce electron bombardment, positioning the sample downfield from the glow zone, the use of monomers containing polymerizable double bonds and the use of a cold substrate to condense vapor simultaneously with plasma deposition.

  19. Ceria-based solid catalysts for organic chemistry.

    PubMed

    Vivier, Laurence; Duprez, Daniel

    2010-06-21

    Ceria has been the subject of thorough investigations, mainly because of its use as an active component of catalytic converters for the treatment of exhaust gases. However, ceria-based catalysts have also been developed for different applications in organic chemistry. The redox and acid-base properties of ceria, either alone or in the presence of transition metals, are important parameters that allow to activate complex organic molecules and to selectively orient their transformation. Pure ceria is used in several organic reactions, such as the dehydration of alcohols, the alkylation of aromatic compounds, ketone formation, and aldolization, and in redox reactions. Ceria-supported metal catalysts allow the hydrogenation of many unsaturated compounds. They can also be used for coupling or ring-opening reactions. Cerium atoms can be added as dopants to catalytic system or impregnated onto zeolites and mesoporous catalyst materials to improve their performances. This Review demonstrates that the exceptional surface (and sometimes bulk) properties of ceria make cerium-based catalysts very effective for a broad range of organic reactions.

  20. Impact of a Library Instruction Session on Bibliographies of Organic Chemistry Students

    ERIC Educational Resources Information Center

    Kromer, John

    2015-01-01

    Students in Chemistry 254: Organic Chemistry for Majors were required to write a paper about an organic name reaction. Before turning in this assignment, students had the option of attending a one-hour library instruction session covering SciFinder, sources for spectra, ACS Style, and print resources about organic name reactions. Twenty-five…

  1. Organic Chemistry Students' Ideas about Nucleophiles and Electrophiles: The Role of Charges and Mechanisms

    ERIC Educational Resources Information Center

    Anzovino, Mary E.; Bretz, Stacey Lowery

    2015-01-01

    Organic chemistry students struggle with reaction mechanisms and the electron-pushing formalism (EPF) used by practicing organic chemists. Faculty have identified an understanding of nucleophiles and electrophiles as one conceptual prerequisite to mastery of the EPF, but little is known about organic chemistry students' knowledge of nucleophiles…

  2. What Does the Acid Ionization Constant Tell You? An Organic Chemistry Student Guide

    ERIC Educational Resources Information Center

    Rossi, Robert D.

    2013-01-01

    Many students find the transition from first-year general chemistry to second-year organic chemistry a daunting task. There are many reasons for this, not the least of which is their lack of a solid understanding and appreciation of the importance of some basic concepts and principles from general chemistry that play an extremely critical role in…

  3. Analysis of a Distance-Education Program in Organic Chemistry

    NASA Astrophysics Data System (ADS)

    Kurtz, Martha J.; Holden, Brandt E.

    2001-08-01

    Distance education has become a very popular mode for providing education to students who would not otherwise be able to take classes. Although it has been used for lecture courses in chemistry, little is known about its relative effectiveness compared to on-site courses with regard to student performance. This study compared sections of organic chemistry in which distance education was the learning mode with sections that were taught on site. All sections were instructed in a team-teaching format. A local instructor taught the lab sections at all locations and lab reports were forwarded to the on-campus faculty via email. Surveys were prepared and administered to all sections of students for qualitative assessment. The surveys provided information on student attitudes toward distance learning as well as the corresponding lab section, team-teaching techniques, and course Web page. Exam and spatial ability scores were statistically analyzed to determine quantitative differences. The data revealed no statistically significant differences between the performance of the students learning by distance education and those in regular sections.

  4. Development and Implementation of a Two-Semester Introductory Organic-Bioorganic Chemistry Sequence: Conclusions from the First Six Years

    ERIC Educational Resources Information Center

    Goess, Brian C.

    2014-01-01

    A two-semester second-year introductory organic chemistry sequence featuring one semester of accelerated organic chemistry followed by one semester of bioorganic chemistry is described. Assessment data collected over a six-year period reveal that such a course sequence can facilitate student mastery of fundamental organic chemistry in the first…

  5. Ethanol Metabolism and the Transition from Organic Chemistry to Biochemistry

    NASA Astrophysics Data System (ADS)

    Feinman, Richard D.

    2001-09-01

    To ease the transition from organic chemistry at the beginning of a biochemistry course or at the beginning of the metabolism section of the organic course, an early presentation of the oxidation of ethanol is proposed. Alcohol dehydrogenase and aldehyde dehydrogenase reactions can smooth the introduction to biochemistry, since they involve three of the simplest compounds: ethanol, acetaldehyde, and acetic acid. Using these reactions as a model encourages the study of metabolic pathways by a systematic approach rather than by rote memorization. Reactions that can be presented as variations on a theme include methanol poisoning, the polyol reaction, and, most important, the sequence glycerol-3-phosphate to glyceraldehyde-3-phosphate to 3-phosphoglyceric acid. This last sequence integrates lipid and carbohydrate metabolism and, by comparison with the model reaction, brings out the principles of substrate-level phosphorylation. The method has evoked favorable verbal feedback from students and, in addition to medical and graduate courses, has been successfully used in the biochemical section of an undergraduate organic course.

  6. Irradiated Benzene Ice Provides Clues to Meteoritic Organic Chemistry

    NASA Technical Reports Server (NTRS)

    Callahan, Michael Patrick; Gerakines, Perry Alexander; Martin, Mildred G.; Hudson, Reggie L.; Peeters, Zan

    2013-01-01

    Aromatic hydrocarbons account for a significant portion of the organic matter in carbonaceous chondrite meteorites, as a component of both the low molecular weight, solvent-extractable compounds and the insoluble organic macromolecular material. Previous work has suggested that the aromatic compounds in carbonaceous chondrites may have originated in the radiation-processed icy mantles of interstellar dust grains. Here we report new studies of the organic residue made from benzene irradiated at 19 K by 0.8 MeV protons. Polyphenyls with up to four rings were unambiguously identified in the residue by gas chromatography-mass spectrometry. Atmospheric pressure photoionization Fourier transform mass spectrometry was used to determine molecular composition, and accurate mass measurements suggested the presence of polyphenyls, partially hydrogenated polyphenyls, and other complex aromatic compounds. The profile of low molecular weight compounds in the residue compared well with extracts from the Murchison and Orgueil meteorites. These results are consistent with the possibility that solid phase radiation chemistry of benzene produced some of the complex aromatics found in meteorites.

  7. Spatial ability and its role in organic chemistry: A study of four organic courses

    NASA Astrophysics Data System (ADS)

    Pribyl, Jeffrey R.; Bodner, George M.

    The relationship between spatial ability and performance in organic chemistry was studied in four organic chemistry courses designed for students with a variety of majors including agriculture, biology, health sciences, pre-med, pre-vet, pharmacy, medicinal chemistry, chemistry, and chemical engineering.Students with high spatial scores did significantly better on questions which required problem solving skills, such as completing a reaction or outlining a multi-step synthesis, and questions which required students to mentally manipulate two-dimensional representations of a molecule. Spatial ability was not significant, however, for questions which could be answered by rote memory or by the application of simple algorithms.Students who drew preliminary figures or extra figures when answering questions were more likely to get the correct answer. High spatial ability students were more likely to draw preliminary figures, even for questions that did not explicitly require these drawings. When questions required preliminary or extra figures, low spatial ability students were more likely to draw figures that were incorrect. Low spatial ability students were also more likely to draw structures that were lopsided, ill-proportioned, and nonsymmetric.The results of this study are interpreted in terms of a model which argues that high spatial ability students are better at the early stages of problem solving described as understanding the problem. A model is also discussed which explains why students who draw preliminary or extra figures for questions are more likely to get correct answers.

  8. How the Principles of Green Chemistry Changed the Way Organic Chemistry Labs Are Taught at the University of Detroit Mercy

    NASA Astrophysics Data System (ADS)

    Mio, Matthew J.

    2017-02-01

    Many logistic and instructional changes followed the incorporation of the 12 principles of green chemistry into organic chemistry laboratory courses at the University of Detroit Mercy. Over the last decade, institutional limitations have been turned into green chemical strengths in many areas, including integration of atom economy metrics into learning outcomes, replacing overly toxic equipment and reagents, and modifying matters of reaction scale and type.

  9. Perception of the Relevance of Organic Chemistry in a German Pharmacy Students' Course.

    PubMed

    Wehle, Sarah; Decker, Michael

    2016-04-25

    Objective. To investigate German pharmacy students' attitudes toward the relevance of organic chemistry training in Julius Maximilian University (JMU) of Würzburg with regard to subsequent courses in the curricula and in later prospective career options. Methods. Surveys were conducted in the second-year organic chemistry course (50 participants) as well as during the third-year and fourth-year lecture cycle on medicinal and pharmaceutical chemistry (66 participants) in 2014. Results. Students' attitudes were surprisingly consistent throughout the progress of the degree course. Students considered organic chemistry very relevant to the pharmacy study program (95% junior and 97% senior students), and of importance for their future pharmacy program (88% junior and 94% senior students). With regard to prospective career options, the perceived relevance was considerably lower and attitudes were less homogenous. Conclusions. German pharmacy students at JMU Würzburg consider organic chemistry of high relevance for medicinal chemistry and other courses in JMU's pharmacy program.

  10. Analysis of the Effect of Sequencing Lecture and Laboratory Instruction on Student Learning and Motivation Towards Learning Chemistry in an Organic Chemistry Lecture Course

    ERIC Educational Resources Information Center

    Pakhira, Deblina

    2012-01-01

    Exposure to organic chemistry concepts in the laboratory can positively affect student performance, learning new chemistry concepts and building motivation towards learning chemistry in the lecture. In this study, quantitative methods were employed to assess differences in student performance, learning, and motivation in an organic chemistry…

  11. Surface chemistry for molecular layer deposition of organic and hybrid organic-inorganic polymers.

    PubMed

    George, Steven M; Yoon, Byunghoon; Dameron, Arrelaine A

    2009-04-21

    The fabrication of many devices in modern technology requires techniques for growing thin films. As devices miniaturize, manufacturers will need to control thin film growth at the atomic level. Because many devices have challenging morphologies, thin films must be able to coat conformally on structures with high aspect ratios. Techniques based on atomic layer deposition (ALD), a special type of chemical vapor deposition, allow for the growth of ultra-thin and conformal films of inorganic materials using sequential, self-limiting reactions. Molecular layer deposition (MLD) methods extend this strategy to include organic and hybrid organic-inorganic polymeric materials. In this Account, we provide an overview of the surface chemistry for the MLD of organic and hybrid organic-inorganic polymers and examine a variety of surface chemistry strategies for growing polymer thin films. Previously, surface chemistry for the MLD of organic polymers such as polyamides and polyimides has used two-step AB reaction cycles using homo-bifunctional reactants. However, these reagents can react twice and eliminate active sites on the growing polymer surface. To avoid this problem, we can employ alternative precursors for MLD based on hetero-bifunctional reactants and ring-opening reactions. We can also use surface activation or protected chemical functional groups. In addition, we can combine the reactants for ALD and MLD to grow hybrid organic-inorganic polymers that should display interesting properties. For example, using trimethylaluminum (TMA) and various diols as reactants, we can achieve the MLD of alucone organic-inorganic polymers. We can alter the chemical and physical properties of these organic-inorganic polymers by varying the organic constituent in the diol or blending the alucone MLD films with purely inorganic ALD films to build a nanocomposite or nanolaminate. The combination of ALD and MLD reactants enlarges the number of possible sequential self-limiting surface

  12. Organic Chemistry and the Native Plants of the Sonoran Desert: Conversion of Jojoba Oil to Biodiesel

    ERIC Educational Resources Information Center

    Daconta, Lisa V.; Minger, Timothy; Nedelkova, Valentina; Zikopoulos, John N.

    2015-01-01

    A new, general approach to the organic chemistry laboratory is introduced that is based on learning about organic chemistry techniques and research methods by exploring the natural products found in local native plants. As an example of this approach for the Sonoran desert region, the extraction of jojoba oil and its transesterification to…

  13. Trends in the Teaching of Organic Chemistry: A Survey of Some Textbooks.

    ERIC Educational Resources Information Center

    Wheeler, Desmond M. S.; Wheeler, Margaret M.

    1982-01-01

    Following brief highlights of the development of organic chemistry, surveys undergraduate organic chemistry textbooks published in English since 1887 to see how the presentation of the subject has changed over the last 100 years. Coverage is restricted to texts designed for courses lasting one year or more. (Author/JN)

  14. The Chemical World of Paul Walden: Organic Chemistry from 1880 to 1935

    ERIC Educational Resources Information Center

    Tarbell, D. Stanley

    1974-01-01

    Describes Paul Walden's history of organic chemistry as a continuation of Carl Graebe's work, covering the period from 1880 to 1935. Indicates that a general intellectual outlook, controlling ideas, and mental furnishings characteristic of his time are revealed besides factual information about the classical age of organic chemistry. (CC)

  15. Evaluation of a Flipped, Large-Enrollment Organic Chemistry Course on Student Attitude and Achievement

    ERIC Educational Resources Information Center

    Mooring, Suazette R.; Mitchell, Chloe E.; Burrows, Nikita L.

    2016-01-01

    Organic Chemistry is recognized as a course that presents many difficulties and conceptual challenges for students. To combat the high failure rates and poor student attitudes associated with this challenging course, we implemented a "flipped" model for the first-semester, large-enrollment, Organic Chemistry course. In this flipped…

  16. Using Structure-Based Organic Chemistry Online Tutorials with Automated Correction for Student Practice and Review

    ERIC Educational Resources Information Center

    O'Sullivan, Timothy P.; Hargaden, Gra´inne C.

    2014-01-01

    This article describes the development and implementation of an open-access organic chemistry question bank for online tutorials and assessments at University College Cork and Dublin Institute of Technology. SOCOT (structure-based organic chemistry online tutorials) may be used to supplement traditional small-group tutorials, thereby allowing…

  17. Student Perceptions of Online Homework Use for Formative Assessment of Learning in Organic Chemistry

    ERIC Educational Resources Information Center

    Richards-Babb, Michelle; Curtis, Reagan; Georgieva, Zornitsa; Penn, John H.

    2015-01-01

    Use of online homework as a formative assessment tool for organic chemistry coursework was examined. Student perceptions of online homework in terms of (i) its ranking relative to other course aspects, (ii) their learning of organic chemistry, and (iii) whether it improved their study habits and how students used it as a learning tool were…

  18. Integration of Video-Based Demonstrations to Prepare Students for the Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Nadelson, Louis S.; Scaggs, Jonathan; Sheffield, Colin; McDougal, Owen M.

    2015-01-01

    Consistent, high-quality introductions to organic chemistry laboratory techniques effectively and efficiently support student learning in the organic chemistry laboratory. In this work, we developed and deployed a series of instructional videos to communicate core laboratory techniques and concepts. Using a quasi-experimental design, we tested the…

  19. Introducing Undergraduates to Research Using a Suzuki-Miyaura Cross-Coupling Organic Chemistry Miniproject

    ERIC Educational Resources Information Center

    Oliveira, Deyvid G. M.; Rosa, Clarissa H.; Vargas, Bruna P.; Rosa, Diego S.; Silveira, Ma´rcia V.; de Moura, Neusa F.; Rosa, Gilber R.

    2015-01-01

    A five-week miniproject is described for an upper-division experimental organic chemistry course. The activities include synthesis of a phenylboronic acid via a Grignard reaction and its use in a Suzuki-Miyaura cross-coupling reaction. Technical skills and concepts normally presented in practical organic chemistry courses are covered, including…

  20. Factors related to achievement in sophomore organic chemistry at the University of Arkansas

    NASA Astrophysics Data System (ADS)

    Lindsay, Harriet Arlene

    The purpose of this study was to identify the significant cognitive and non-cognitive variables that related to achievement in the first semester of organic chemistry at the University of Arkansas. Cognitive variables included second semester general chemistry grade, ACT composite score, ACT English, mathematics, reading, and science reasoning subscores, and spatial ability. Non-cognitive variables included anxiety, confidence, effectance motivation, and usefulness. Using a correlation research design, the individual relationships between organic chemistry achievement and each of the cognitive variables and non-cognitive variables were assessed. In addition, the relationships between organic chemistry achievement and combinations of these independent variables were explored. Finally, gender- and instructor-related differences in the relationships between organic chemistry achievement and the independent variables were investigated. The samples consisted of volunteers from the Fall 1999 and Fall 2000 sections of Organic Chemistry I at the University of Arkansas. All students in each section were asked to participate. Data for spatial ability and non-cognitive independent variables were collected using the Purdue Visualization of Rotations test and the modified Fennema-Sherman Attitude Scales. Data for other independent variables, including ACT scores and second semester general chemistry grades, were obtained from the Office of Institutional Research. The dependent variable, organic chemistry achievement, was measured by each student's accumulated points in the course and consisted of scores on quizzes and exams in the lecture section only. These totals were obtained from the lecture instructor at the end of each semester. Pearson correlation and stepwise multiple regression analyses were used to measure the relationships between organic chemistry achievement and the independent variables. Prior performance in chemistry as measured by second semester general

  1. Aqueous organic chemistry in the atmosphere: sources and chemical processing of organic aerosols.

    PubMed

    McNeill, V Faye

    2015-02-03

    Over the past decade, it has become clear that aqueous chemical processes occurring in cloud droplets and wet atmospheric particles are an important source of organic atmospheric particulate matter. Reactions of water-soluble volatile (or semivolatile) organic gases (VOCs or SVOCs) in these aqueous media lead to the formation of highly oxidized organic particulate matter (secondary organic aerosol; SOA) and key tracer species, such as organosulfates. These processes are often driven by a combination of anthropogenic and biogenic emissions, and therefore their accurate representation in models is important for effective air quality management. Despite considerable progress, mechanistic understanding of some key aqueous processes is still lacking, and these pathways are incompletely represented in 3D atmospheric chemistry and air quality models. In this article, the concepts, historical context, and current state of the science of aqueous pathways of SOA formation are discussed.

  2. Iodine-124: a promising positron emitter for organic PET chemistry.

    PubMed

    Koehler, Lena; Gagnon, Katherine; McQuarrie, Steve; Wuest, Frank

    2010-04-13

    The use of radiopharmaceuticals for molecular imaging of biochemical and physiological processes in vivo has evolved into an important diagnostic tool in modern nuclear medicine and medical research. Positron emission tomography (PET) is currently the most sophisticated molecular imaging methodology, mainly due to the unrivalled high sensitivity which allows for the studying of biochemistry in vivo on the molecular level. The most frequently used radionuclides for PET have relatively short half-lives (e.g. 11C: 20.4 min; 18F: 109.8 min) which may limit both the synthesis procedures and the time frame of PET studies. Iodine-124 (124I, t1/2 = 4.2 d) is an alternative long-lived PET radionuclide attracting increasing interest for long term clinical and small animal PET studies. The present review gives a survey on the use of 124I as promising PET radionuclide for molecular imaging. The first part describes the production of 124I. The second part covers basic radiochemistry with 124I focused on the synthesis of 124I-labeled compounds for molecular imaging purposes. The review concludes with a summary and an outlook on the future prospective of using the long-lived positron emitter 124I in the field of organic PET chemistry and molecular imaging.

  3. Organic Chemistry, 2nd Edition (by Paula Y. Bruice)

    NASA Astrophysics Data System (ADS)

    Katz, Marlene G.

    1998-11-01

    Prentice Hall: Englewood Cliffs, NJ, 1998, xxx +1256 pp, 6 appendices. ISBN 0-13-841925-6. $99. The author has made some constructive changes to the second edition of this visually pleasing book. The chapter order has been rearranged so that all of spectroscopy is covered in two adjoining chapters (new problems combining NMR and IR have been added), all of the chapters on bioorganic chemistry are grouped together (information on reducing sugars has been added), and the last section now covers heterocycles, pericyclic reactions, polymer synthesis, multistep synthetic strategies, and drug design. The publisher offers additional material at its Web site and a paperback for students assisting them in using the Internet. The ChemCentral Organic Web site has problem sets to supplement each chapter (including hints for struggling students) and animations of molecules undergoing reactions. In addition the Web site provides syllabus construction software for instructors. The accompanying study guide/solutions manual, written by the textbook author, contains a glossary, answers to chapter problems, and a practice test (for the first twenty chapters). There are sections called "special topics" which offer in-depth treatment of pH, pKa, buffers, and the electron-pushing formalism.

  4. The ACS Exams Institute Undergraduate Chemistry Anchoring Concepts Content Map II: Organic Chemistry

    ERIC Educational Resources Information Center

    Raker, Jeffrey; Holme, Thomas; Murphy, Kristen

    2013-01-01

    As a way to assist chemistry departments with programmatic assessment of undergraduate chemistry curricula, the ACS Examinations Institute is devising a map of the content taught throughout the undergraduate curriculum. The structure of the map is hierarchal, with large grain size at the top and more content detail as one moves "down"…

  5. Comparing Recent Organizing Templates for Test Content between ACS Exams in General Chemistry and AP Chemistry

    ERIC Educational Resources Information Center

    Holme, Thomas

    2014-01-01

    Two different versions of "big ideas" rooted content maps have recently been published for general chemistry. As embodied in the content outline from the College Board, one of these maps is designed to guide curriculum development and testing for advanced placement (AP) chemistry. The Anchoring Concepts Content Map for general chemistry…

  6. A Collaborative, Wiki-Based Organic Chemistry Project Incorporating Free Chemistry Software on the Web

    ERIC Educational Resources Information Center

    Evans, Michael J.; Moore, Jeffrey S.

    2011-01-01

    In recent years, postsecondary instructors have recognized the potential of wikis to transform the way students learn in a collaborative environment. However, few instructors have embraced in-depth student use of chemistry software for the creation of interactive chemistry content on the Web. Using currently available software, students are able…

  7. Students' Understanding of Acids/Bases in Organic Chemistry Contexts

    ERIC Educational Resources Information Center

    Cartrette, David P.; Mayo, Provi M.

    2011-01-01

    Understanding key foundational principles is vital to learning chemistry across different contexts. One such foundational principle is the acid/base behavior of molecules. In the general chemistry sequence, the Bronsted-Lowry theory is stressed, because it lends itself well to studying equilibrium and kinetics. However, the Lewis theory of…

  8. Lunar carbon chemistry - Relations to and implications for terrestrial organic geochemistry.

    NASA Technical Reports Server (NTRS)

    Eglinton, G.; Maxwell, J. R.; Pillinger, C. T.

    1972-01-01

    Survey of the various ways in which studies of lunar carbon chemistry have beneficially affected terrestrial organic geochemistry. A lunar organic gas-analysis operating system is cited as the most important instrumental development in relation to terrestrial organic geochemistry. Improved methods of analysis and handling of organic samples are cited as another benefit derived from studies of lunar carbon chemistry. The problem of controlling contamination and minimizing organic vapors is considered, as well as the possibility of analyzing terrestrial samples by the techniques developed for lunar samples. A need for new methods of analyzing carbonaceous material which is insoluble in organic solvents is indicated.

  9. Integrating Chemical Information Instruction into the Chemistry Curriculum on Borrowed Time: A Multiyear Case Study of a Capstone Research Report for Organic Chemistry

    ERIC Educational Resources Information Center

    Jacobs, Danielle L.; Dalal, Heather A.; Dawson, Patricia H.

    2016-01-01

    To develop information literacy skills in chemistry and biochemistry majors at a primarily undergraduate institution, a multiyear collaboration between chemistry faculty and librarians has resulted in the establishment of a semester-long capstone project for Organic Chemistry II. Information literacy skills were instilled via a progressive…

  10. Organic Carbamates in Drug Design and Medicinal Chemistry

    PubMed Central

    2016-01-01

    The carbamate group is a key structural motif in many approved drugs and prodrugs. There is an increasing use of carbamates in medicinal chemistry and many derivatives are specifically designed to make drug–target interactions through their carbamate moiety. In this Perspective, we present properties and stabilities of carbamates, reagents and chemical methodologies for the synthesis of carbamates, and recent applications of carbamates in drug design and medicinal chemistry. PMID:25565044

  11. Organic carbamates in drug design and medicinal chemistry.

    PubMed

    Ghosh, Arun K; Brindisi, Margherita

    2015-04-09

    The carbamate group is a key structural motif in many approved drugs and prodrugs. There is an increasing use of carbamates in medicinal chemistry and many derivatives are specifically designed to make drug-target interactions through their carbamate moiety. In this Perspective, we present properties and stabilities of carbamates, reagents and chemical methodologies for the synthesis of carbamates, and recent applications of carbamates in drug design and medicinal chemistry.

  12. Chemistry of secondary organic aerosol: Formation and evolution of low-volatility organics in the atmosphere

    NASA Astrophysics Data System (ADS)

    Kroll, Jesse H.; Seinfeld, John H.

    2008-05-01

    Secondary organic aerosol (SOA), particulate matter composed of compounds formed from the atmospheric transformation of organic species, accounts for a substantial fraction of tropospheric aerosol. The formation of low-volatility (semivolatile and possibly nonvolatile) compounds that make up SOA is governed by a complex series of reactions of a large number of organic species, so the experimental characterization and theoretical description of SOA formation presents a substantial challenge. In this review we outline what is known about the chemistry of formation and continuing transformation of low-volatility species in the atmosphere. The primary focus is chemical processes that can change the volatility of organic compounds: (1) oxidation reactions in the gas phase, (2) reactions in the particle phase, and (3) continuing chemistry (in either phase) over several generations. Gas-phase oxidation reactions can reduce volatility by the addition of polar functional groups or increase it by the cleavage of carbon-carbon bonds; key branch points that control volatility are the initial attack of the oxidant, reactions of alkylperoxy (RO2) radicals, and reactions of alkoxy (RO) radicals. Reactions in the particle phase include oxidation reactions as well as accretion reactions, non-oxidative processes leading to the formation of high-molecular-weight species. Organic carbon in the atmosphere is continually subject to reactions in the gas and particle phases throughout its atmospheric lifetime (until lost by physical deposition or oxidized to CO or CO2), implying continual changes in volatility over the timescales of several days. The volatility changes arising from these chemical reactions must be parameterized and included in models in order to gain a quantitative and predictive understanding of SOA formation.

  13. A Simple Assignment that Enhances Students' Ability to Solve Organic Chemistry Synthesis Problems and Understand Mechanisms

    ERIC Educational Resources Information Center

    Teixeira, Jennifer; Holman, R. W.

    2008-01-01

    Organic chemistry students typically struggle with the retrosynthetic approach to solving synthesis problems because most textbooks present the chemistry grouped by "reactions of the functional group". In contrast, the retrosynthetic approach requires the student to envision "reactions that yield the functional group". A second challenge is the…

  14. On the Successful Use of Inquiry-Driven Experiments in the Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Mohrig, Jerry R.; Hammond, Christina Noring; Colby, David A.

    2007-01-01

    The mix of guided-inquiry and design based experiments is feasible to do in introductory organic chemistry lab courses. It can provide students with experience in two parts of experimental chemistry such as the significance and careful analysis of experimental data and the design of experiments.

  15. Synthesis and Characterization of Calixarene Tetraethers: An Exercise in Supramolecular Chemistry for the Undergraduate Organic Laboratory

    ERIC Educational Resources Information Center

    Debbert, Stefan L.; Hoh, Bradley D.; Dulak, David J.

    2016-01-01

    In this experiment for an introductory undergraduate organic chemistry lab, students tetraalkylate tertbutylcalix[4]arene, a bowl-shaped macrocyclic oligophenol, and examine the supramolecular chemistry of the tetraether product by proton nuclear magnetic resonance (NMR) spectroscopy. Complexation with a sodium ion reduces the conformational…

  16. Ethnically Diverse Students' Knowledge Structures in First-Semester Organic Chemistry

    ERIC Educational Resources Information Center

    Lopez, Enrique J.; Shavelson, Richard J.; Nandagopal, Kiruthiga; Szu, Evan; Penn, John

    2014-01-01

    Chemistry courses remain a challenge for many undergraduate students. In particular, first-semester organic chemistry has been labeled as a gatekeeper with high attrition rates, especially among students of color. Our study examines a key factor related to conceptual understanding in science and predictive of course outcomes-knowledge structures.…

  17. An Asymptotic Approach to the Development of a Green Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Goodwin, Thomas E.

    2004-01-01

    Green chemistry is the utilization of a set of principles that reduces or eliminates the use or generation of hazardous substances in the design, manufacture and application of chemical products. Some of the philosophical questions and practical decisions that have guided the greening of the organic chemistry laboratory at Hendrix College in…

  18. Comparable Educational Benefits in Half the Time: An Alternating Organic Chemistry Laboratory Sequence Targeting Prehealth Students

    ERIC Educational Resources Information Center

    Young, Sherri C.; Colabroy, Keri L.; Baar, Marsha R.

    2016-01-01

    The laboratory is a mainstay in STEM education, promoting the development of critical thinking skills, dexterity, and scientific curiosity. The goals in the laboratory for nonchemistry, prehealth majors, though, could be distinguished from those for chemistry majors. In service courses such as organic chemistry, much laboratory time is often spent…

  19. Intuitive Judgments Govern Students' Answering Patterns in Multiple-Choice Exercises in Organic Chemistry

    ERIC Educational Resources Information Center

    Graulich, Nicole

    2015-01-01

    Research in chemistry education has revealed that students going through their undergraduate and graduate studies in organic chemistry have a fragmented conceptual knowledge of the subject. Rote memorization, rule-based reasoning, and heuristic strategies seem to strongly influence students' performances. There appears to be a gap between what we…

  20. The Tip of the Iceberg in Organic Chemistry Classes: How Do Students Deal with the Invisible?

    ERIC Educational Resources Information Center

    Graulich, Nicole

    2015-01-01

    Organic chemistry education is one of the youngest research areas among all chemistry related research efforts, and its published scholarly work has become vibrant and diverse over the last 15 years. Research on problem-solving behavior, students' use of the arrow-pushing formalism, the investigation of students' conceptual knowledge and…

  1. Environmental Organic Chemistry, 2nd Edition (Rene P. Schwarzenback, Philip M. Gschwend, and Dieter M. Imboden)

    NASA Astrophysics Data System (ADS)

    Lee, Cindy M.

    2003-10-01

    In summary the authors have added substantially new material and improved the consistency of presentation in this second edition. This text should continue to be the leader in the field of environmental organic chemistry.

  2. Microwave-Assisted Chemistry: A Rapid and Sustainable Route to Synthesis of Organics and Nanomaterials

    EPA Science Inventory

    The use of emerging MW-assisted chemistry techniques in conjunction with benign reaction media is dramatically reducing chemical waste and reaction times in several organic syntheses and chemical transformations. This review summarizes recent developments in MW-assisted synthesis...

  3. Beilstein Without Tears: Education in the Use of the Literature of Organic Chemistry.

    ERIC Educational Resources Information Center

    Callaghan, Patricia M.; And Others

    1986-01-01

    The use of Beilstein ("Handbuch der Organischen Chemie") in the early stages of a second-year, one semester course in organic chemistry is described. Student literature projects, evaluation, use of ancillary literature, and a sample search are included. (JN)

  4. Improvements to the characterization of organic nitrogen chemistry and deposition in CMAQ

    EPA Science Inventory

    Excess atmospheric nitrogen deposition can cause significant harmful effects to ecosystems. Organic nitrogen deposition can be an important contributor to the total nitrogen budget, contributing 10-30%, however there are large uncertainties in the chemistry and deposition of thes...

  5. Improvements to the characterization of organic nitrogen chemistry and deposition in CMAQ (CMAS Presentation)

    EPA Science Inventory

    Excess atmospheric nitrogen deposition can cause significant harmful effects to ecosystems. Organic nitrogen deposition can be an important contributor to the total nitrogen budget, contributing 10-30%, however there are large uncertainties in the chemistry and deposition of thes...

  6. Improvements to the treatment of organic nitrogen chemistry & deposition in CMAQ

    EPA Science Inventory

    Excess atmospheric nitrogen deposition can cause significant harmful effects to ecosystems. Organic nitrogen deposition can be an important contributor to the total nitrogen budget, contributing 10-30%, however there are large uncertainties in the chemistry and deposition of thes...

  7. High-Throughput Synthetic Chemistry Enabled by Organic Solvent Disintegrating Tablet.

    PubMed

    Li, Tingting; Xu, Lei; Xing, Yanjun; Xu, Bo

    2017-01-17

    Synthetic chemistry remains a time- and labor-intensive process of inherent hazardous nature. Our organic solvent disintegrating tablet (O-Tab) technology has shown potential to make industrial/synthetic chemistry more efficient. As is the case with pharmaceutical tablets, our reagent-containing O-Tabs are mechanically strong, but disintegrate rapidly when in contact with reaction media (organic solvents). For O-Tabs containing sensitive chemicals, they can be further coated to insulate them from air and moisture.

  8. The interfacial chemistry of organic materials on commercial glass surfaces

    NASA Astrophysics Data System (ADS)

    Banerjee, Joy

    The hydrolytic stability of glass is dependent on its composition. Glasses are exposed to water during their processing and in many applications; therefore, their surface or interface with other materials must withstand hydrolytic attack. Multi-component silicate glasses are widely used but have been the least studied. In coatings-based applications, these glasses come in contact with organosilanes and organic molecules where the adsorption may be affected by surface water. For example, the influence of glass composition on the wet strength of a glass/polymer composite material is unclear, but it is presumed to be driven by the hydrolytic stability of the interfacial chemistry. Organosilanes are critical for increasing the performance of composite materials in humid environments but the precise manner by which the improvement occurs has not been verified. The current school of thought is that the application of silane coatings on a multi-component glass surface transforms the chemically heterogeneous surface into a homogenous and hydrolytically stable surface. In this study, multi-component silicate glass surfaces were silanized by both aqueous and non-aqueous methods. The effect of glass composition and surface hydration on silane coverage was quantified by X-ray Photoelectron Spectroscopy (XPS) analysis. The monolayer-level adsorption results showed that the low-sodium content glasses had greater coverage than a high-sodium content glass in dry conditions in contrast to an equivalent coverage in wet conditions. The hydrolytically-stable coverage on multi-component silicate glass surfaces by both silanization methods was found to be sub-monolayer. A thin film model in conjunction with XPS and Infrared Spectroscopy was used to probe the interfacial region of a fiberglass insulation material containing a sodium-rich multi-component silicate glass and an acrylate resin binder. Upon the application of the aqueous binder, the leaching of sodium from the glass promoted

  9. Profiles in chemistry: a historical perspective on the national organic symposium.

    PubMed

    Fenlon, Edward E; Myers, Brian J

    2013-06-21

    This perspective delineates the history of the National Organic Chemistry Symposium (NOS) and, in doing so, traces the development of organic chemistry over the past 88 years. The NOS is the premier event sponsored by the ACS Division of Organic Chemistry (ORGN) and has been held in odd-numbered years since 1925, with the exceptions of 1943 and 1945. During the 42 symposia, 332 chemists have given 549 plenary lectures. The role the NOS played in the launch of The Journal of Organic Chemistry and Organic Reactions and the initiation of the Roger Adams Award are discussed. Representative examples highlighting the chemistry presented in each era are described, and the evolution of the field is examined by assigning each NOS talk to one of seven subdisciplines and analyzing how the number of talks in each subdiscipline has changed over time. Comparisons of the demographics of speakers, attendees, and ORGN members are made, and superlatives are noted. Personal interest stories of the speakers are discussed, along with the relationships among them, especially their academic lineage. Logistical aspects of the NOS and their historical trends are reviewed. Finally, the human side of science is examined, where over the past century, the NOS has been intertwined with some of the most heated debates in organic chemistry. Conflicts and controversies involving free radicals, reaction mechanisms, and nonclassical carbocations are discussed.

  10. TextRev: A Window into How General and Organic Chemistry Students Use Textbook Resources

    NASA Astrophysics Data System (ADS)

    Smith, Bradley D.; Jacobs, Dennis C.

    2003-01-01

    A paper-based survey of first-year general chemistry and second-year organic chemistry students included responses from approximately 3200 students at nine colleges and universities. The students answered questions about the time they spent using various textbook resources, and about the quality and helpfulness of each resource. Five important results emerged. Organic chemistry students report spending approximately 40% more time using textbook resources than do general chemistry students. For general chemistry students, the order of average self-reported hours per week using textbook resources correlates with anticipated grades in the following way, C > B > A; whereas the hours per week for organic students is independent of anticipated grade. Compared to general chemistry students, the organic chemistry students spend a smaller fraction of their time using the textbook and more time using the study guide or solutions manual. Both groups spend less than 7% of their time using the textbook’s Web site or the accompanying CD. Both groups find in-chapter example problems and end-of-chapter problems to be the most helpful textbook features.

  11. Integration of Computational Chemistry into the Undergraduate Organic Chemistry Laboratory Curriculum

    ERIC Educational Resources Information Center

    Esselman, Brian J.; Hill, Nicholas J.

    2016-01-01

    Advances in software and hardware have promoted the use of computational chemistry in all branches of chemical research to probe important chemical concepts and to support experimentation. Consequently, it has become imperative that students in the modern undergraduate curriculum become adept at performing simple calculations using computational…

  12. Measuring Meaningful Learning in the Undergraduate General Chemistry and Organic Chemistry Laboratories: A Longitudinal Study

    ERIC Educational Resources Information Center

    Galloway, Kelli R.; Bretz, Stacey Lowery

    2015-01-01

    Understanding how students learn in the undergraduate chemistry teaching laboratory is an essential component to developing evidence-based laboratory curricula. The Meaningful Learning in the Laboratory Instrument (MLLI) was developed to measure students' cognitive and affective expectations and experiences for learning in the chemistry…

  13. Problem Types in Synthetic Organic Chemistry Research: Implications for the Development of Curricular Problems for Second-Year Level Organic Chemistry Instruction

    ERIC Educational Resources Information Center

    Raker, Jeffrey R.; Towns, Marcy H.

    2012-01-01

    Understanding of the nature of science is key to the development of new curricular materials that mirror the practice of science. Three problem types (project level, synthetic planning, and day-to-day) in synthetic organic chemistry emerged during a thematic content analysis of the research experiences of eight practising synthetic organic…

  14. Beyond Clickers, Next Generation Classroom Response Systems for Organic Chemistry

    ERIC Educational Resources Information Center

    Shea, Kevin M.

    2016-01-01

    Web-based classroom response systems offer a variety of benefits versus traditional clicker technology. They are simple to use for students and faculty and offer various question types suitable for a broad spectrum of chemistry classes. They facilitate active learning pedagogies like peer instruction and successfully engage students in the…

  15. Motivational Beliefs and Learning Strategies in Organic Chemistry

    ERIC Educational Resources Information Center

    Lynch, Douglas Jay; Trujillo, Hernando

    2011-01-01

    Students enter college chemistry courses with different sources of motivation, appropriate or inappropriate assumptions about their probability of success and how to study. This study is theoretically aligned with self-regulated learning research. Clearly, academic performance is closely related to student motivational beliefs and learning…

  16. Synthesis and Metalation of a Ligand: An Interdisciplinary Laboratory Experiment for Second-Year Organic and Introductory Inorganic Chemistry Students

    ERIC Educational Resources Information Center

    Kasting, Benjamin J.; Bowser, Andrew K.; Anderson-Wile, Amelia M.; Wile, Bradley M.

    2015-01-01

    An interdisciplinary laboratory experiment involving second-year undergraduate organic chemistry and introductory inorganic chemistry undergraduate students is described. Organic chemistry students prepare a series of amine-bis(phenols) via a Mannich reaction, and characterize their products using melting point; FTIR; and [superscript 1]H,…

  17. "Molecules-in-Medicine": Peer-Evaluated Presentations in a Fast-Paced Organic Chemistry Course for Medical Students

    ERIC Educational Resources Information Center

    Kadnikova, Ekaterina N.

    2013-01-01

    To accentuate the importance of organic chemistry in development of contemporary pharmaceuticals, a three-week unit entitled "Molecules-in-Medicine" was included in the curriculum of a comprehensive one-semester four-credit organic chemistry course. After a lecture on medicinal chemistry concepts and pharmaceutical practices, students…

  18. Effectiveness of Analogy Instructional Strategy on Undergraduate Student's Acquisition of Organic Chemistry Concepts in Mutah University, Jordan

    ERIC Educational Resources Information Center

    Samara, Nawaf Ahmad Hasan

    2016-01-01

    This study aimed at investigating the effectiveness of analogy instructional strategy on undergraduate students' acquisition of organic chemistry concepts in Mutah University, Jordan. A quasi-experimental design was used in the study; Participants were 97 students who enrolled in organic chemistry course at the department of chemistry during the…

  19. CODEX: Assessing the Historical Context of Chemistry and Organics on Mars

    NASA Astrophysics Data System (ADS)

    Anderson, F. Scott; Whitaker, Tom; Levine, Jonathan

    2014-05-01

    The Chemistry, Organics and Dating EXperiment (CODEX) is a laser desorption time-of-flight mass spectrometer designed for use on Mars, which, by varying the type of ionization used, can operate as an elemental detector, an organics detector, and a radiometric dating instrument. CODEX uses three ionization modes: A) laser ablation mass spectrometry (LAMS) to measure chemistry and isotopes, B) two-step laser desorption/ionization mass spectrometry (L2MS) to measure organics, and C) laser desorption resonance ionization mass spectrometry (LDRIMS) to measure rubidium-strontium geochronology. Using these modes sequentially, CODEX interrogates hundreds of locations on the surface of a drill core, each of which are initially cleaned by laser ablation to remove surface contaminants. Using microscopic mapping, CODEX places elemental chemistry observations in spatial and temporal context with organic signatures revealing the complex historical context of chemistry and organics. The modes of CODEX have been demonstrated on three well-known samples: a) the Boulder Creek Granite (chemistry and dating), b) the carbonaceous chondrite Murchison (organics and chemistry), and c) the Martian meteorite Zagami (dating). The BCG measurements result in a high-sensitivity chemistry measurements, with isotope ratio precision exceeding ±0.35%; using dating mode, we derived an average age of 1727±62 Ma, as compared to a TIMS age of 1700±40 Ma. The measurements of the Murchison meteorite revealed hundreds of organic compounds consistent with an abiotic carbonaceous chondrite, and elemental abundances that match previous work. Finally, Zagami is a Martian meteorite with a Rb-Sr age of 166±6 Ma. Our measurements result in an age of 170±105 Ma, consistent with the previously published dates, and an accuracy exceeding NASA requirements (±200 Ma).

  20. Modeling SOAaq Formation: Explicit Organic Chemistry in Cloud Droplets with CMAQ

    NASA Astrophysics Data System (ADS)

    Carlton, A. G.; Sareen, N.; Fahey, K.; Hutzell, W. T.

    2013-12-01

    Aqueous multiphase chemistry in the atmosphere has a substantial impact on climate and can lead to air quality changes that adversely impact human health and the environment. The chemistry is complex because of the variety of compounds present in the atmosphere and the phase transitions associated with multiphase reactions. These reactions can lead to the formation of secondary organic aerosols (SOAAQ) in the atmosphere. When included, current photochemical models typically use a simple parameterization to describe SOAAQ formation. Here, we discuss the implementation of explicit aqueous SOA chemistry in a box model of the CMAQ 5.0.1 aqueous phase chemistry mechanism using the Kinetic PreProcessor (KPP). The expanded chemistry model includes reactions of glyoxal, methylglyoxal, and glycolaldehyde as precursors to form SOAAQ and is based on the mechanism from Lim et. al. 2010. The current aqueous phase chemistry module in CMAQ uses a forward Euler method to solve the system of oxidation equations, estimating the pH with a bisection method assuming electroneutrality, and multiphase processes are solved sequentially. This is not robust for systems with large dynamic range (e.g., multiphase systems), and inhibits expansion of the aqueous phase chemical mechanism to adequately incorporate the growing body of literature that describes multiphase organic chemistry. The KPP solver allows for all processes to be solved simultaneously and facilitates expansion of the current mechanism. Addition of explicit organic reactions and H2O2 photolysis in the KPP box model results in increased mass of organic aerosol and more realistic predictions. For particulate matter focused air quality management strategies to be effective, it is important that models move away from the yield-based approach currently used and expand to include more explicit organic chemistry.

  1. On the Applicability of the Green Chemistry Principles to Sustainability of Organic Matter on Asteroids

    NASA Astrophysics Data System (ADS)

    Kolb, Vera M.

    2010-06-01

    The connection between astrobiology and green chemistry represents a new approach to sustainability of organic matter on asteroids or similar bodies. Green chemistry is chemistry which is environmentally friendly. One obvious way for chemistry to be green is to use water as a solvent, instead of more toxic organic solvents. Many astrobiological reactions occur in the aqueous medium, for example in the prebiotic soup or during the aqueous alteration period on asteroids. Thus any advances in the green organic reactions in water are directly applicable to astrobiology. Another green chemistry approach is to abolish use of toxic solvents. This can be accomplished by carrying out the reactions without a solvent in the solventless or solid-state reactions. The advances in these green reactions are directly applicable to the chemistry on asteroids during the periods when water was not available. Many reactions on asteroids may have been done in the solid mixtures. These reactions may be responsible for a myriad of organic compounds that have been isolated from the meteorites.

  2. Perception of the Relevance of Organic Chemistry in a German Pharmacy Students’ Course

    PubMed Central

    Wehle, Sarah

    2016-01-01

    Objective. To investigate German pharmacy students’ attitudes toward the relevance of organic chemistry training in Julius Maximilian University (JMU) of Würzburg with regard to subsequent courses in the curricula and in later prospective career options. Methods. Surveys were conducted in the second-year organic chemistry course (50 participants) as well as during the third-year and fourth-year lecture cycle on medicinal and pharmaceutical chemistry (66 participants) in 2014. Results. Students’ attitudes were surprisingly consistent throughout the progress of the degree course. Students considered organic chemistry very relevant to the pharmacy study program (95% junior and 97% senior students), and of importance for their future pharmacy program (88% junior and 94% senior students). With regard to prospective career options, the perceived relevance was considerably lower and attitudes were less homogenous. Conclusions. German pharmacy students at JMU Würzburg consider organic chemistry of high relevance for medicinal chemistry and other courses in JMU’s pharmacy program. PMID:27170811

  3. Interstellar Ice Chemistry: From Water to Complex Organics

    NASA Astrophysics Data System (ADS)

    Oberg, Karin I.; Fayolle, E.; Linnartz, H.; van Dishoeck, E.; Fillion, J.; Bertin, M.

    2013-06-01

    Molecular cloud cores, protostellar envelopes and protoplanetary disk midplanes are all characterized by freeze-out of atoms and molecules (other than H and H2) onto interstellar dust grains. On the grain surface, atom addition reactions, especially hydrogenation, are efficient and H2O forms readily from O, CH3OH from CO etc. The result is an icy mantle typically dominated by H2O, but also rich in CO2, CO, NH3, CH3OH and CH4. These ices are further processed through interactions with radiation, electrons and energetic particles. Because of the efficiency of the freeze-out process, and the complex chemistry that succeeds it, these icy grain mantles constitute a major reservoir of volatiles during star formation and are also the source of much of the chemical evolution observed in star forming regions. Laboratory experiments allow us to explore how molecules and radicals desorb, dissociate, diffuse and react in ices when exposed to different sources of energy. Changes in ice composition and structure is constrained using infrared spectroscopy and mass spectrometry. By comparing ice desorption, segregation, and chemistry efficiencies under different experimental conditions, we can characterize the basic ice processes, e.g. diffusion of different species, that underpin the observable changes in ice composition and structure. This information can then be used to predict the interstellar ice chemical evolution. I will review some of the key laboratory discoveries on ice chemistry during the past few years and how they have been used to predict and interpret astronomical observations of ice bands and gas-phase molecules associated with ice evaporation. These include measurements of thermal diffusion in and evaporation from ice mixtures, non-thermal diffusion efficiencies (including the recent results on frequency resolved UV photodesorption), and the expected temperature dependencies of the complex ice chemistry regulated by radical formation and diffusion. Based on these

  4. Provocative Opinion: Let's Talk about the Organic Chemistry Course.

    ERIC Educational Resources Information Center

    Goldish, Dorothy M.

    1988-01-01

    Appraises current organic courses and discusses topics which could be strengthened or dropped. Criticizes the current structure of organic texts and stresses the need for inclusion of useful reactions and mechanisms only. (ML)

  5. Nomenclature101.com: A Free, Student-Driven Organic Chemistry Nomenclature Learning Tool

    ERIC Educational Resources Information Center

    Flynn, Alison B.; Caron, Jeanette; Laroche, Jamey; Daviau-Duguay, Melissa; Marcoux, Caroline; Richard, Gise`le

    2014-01-01

    Fundamental to a student's understanding of organic chemistry is the ability to interpret and use its language, including molecules' names and other key terms. A learning gap exists in that students often struggle with organic nomenclature. Although many resources describe the rules for naming molecules, there is a paucity of resources…

  6. An Undergraduate Organic Chemistry Laboratory: The Facile Hydrogenation of Methyl Trans-Cinnamate

    ERIC Educational Resources Information Center

    O'Connor, Kenneth J.; Zuspan, Kimberly; Berry, Lonnie

    2011-01-01

    Hydrogenation of alkenes is an important reaction in the synthesis of organic molecules. In this experiment, students conduct a high-yield microscale hydrogenation reaction of methyl "trans"-cinnamate using a readily available, safe, and convenient hydrogen source. The conditions are similar to those seen in an organic chemistry textbook for an…

  7. Developing Problem-Solving Skills through Retrosynthetic Analysis and Clickers in Organic Chemistry

    ERIC Educational Resources Information Center

    Flynn, Alison B.

    2011-01-01

    A unique approach to teaching and learning problem-solving and critical-thinking skills in the context of retrosynthetic analysis is described. In this approach, introductory organic chemistry students, who typically see only simple organic structures, undertook partial retrosynthetic analyses of real and complex synthetic targets. Multiple…

  8. A Mass Spectral Chlorine Rule for Use in Structure Determinations in Sophomore Organic Chemistry

    ERIC Educational Resources Information Center

    Gross, Ray A., Jr.

    2004-01-01

    The low-resolution mass spectrum of integral masses is used to determine the number of bromine and chlorine atoms in an organic compound. The chlorine rule is a tool suitable for use in structural determinations in first year organic chemistry and it is supported by the ability of sophomore-level students to successfully determine n and m from the…

  9. A One-Pot, Asymmetric Robinson Annulation in the Organic Chemistry Majors Laboratory

    ERIC Educational Resources Information Center

    Lazarski, Kiel E.; Rich, Alan A.; Mascarenhas, Cheryl M.

    2008-01-01

    The Robinson annulation is a topic of importance in the second-year organic curriculum. A one-pot, enantioselective Robinson annulation is described. The experiment is completed in two lab periods and is geared towards the second-year organic chemistry major. To our knowledge, this is the first example of a one-pot enantioselective Robinson…

  10. A Cost-Effective Two-Part Experiment for Teaching Introductory Organic Chemistry Techniques

    ERIC Educational Resources Information Center

    Sadek, Christopher M.; Brown, Brenna A.; Wan, Hayley

    2011-01-01

    This two-part laboratory experiment is designed to be a cost-effective method for teaching basic organic laboratory techniques (recrystallization, thin-layer chromatography, column chromatography, vacuum filtration, and melting point determination) to large classes of introductory organic chemistry students. Students are exposed to different…

  11. Chemkarta: A Card Game for Teaching Functional Groups in Undergraduate Organic Chemistry

    ERIC Educational Resources Information Center

    Knudtson, Christopher A.

    2015-01-01

    Students in undergraduate organic chemistry courses are frequently overwhelmed by the volume and complexity of information they are expected to learn. To aid in students' learning of organic functional groups, a novel card game "ChemKarta" is reported that can serve as a useful alternative to flashcards. This pedagogy is a simple…

  12. Selective Bifunctional Modification of a Non-catenated Metal-Organic Framework Material via 'Click' Chemistry

    SciTech Connect

    Gadzikwa, Tendai; Farha, Omar K.; Malliakas, Christos D.; Kanatzidis, Mercouri G.; Hupp, Joseph T.; Nguyen, SonBinh T.; NWU

    2009-12-01

    A noncatenated, Zn-based metal-organic framework (MOF) material bearing silyl-protected acetylenes was constructed and postsynthetically modified using 'click' chemistry. Using a solvent-based, selective deprotection strategy, two different organic azides were 'clicked' onto the MOF crystals, resulting in a porous material whose internal and external surfaces are differently functionalized.

  13. Student Perceptions of the Benefits of a Learner-Based Writing Assignment in Organic Chemistry

    ERIC Educational Resources Information Center

    Ablin, Lois

    2008-01-01

    A writing assignment to increase student understanding of and interest in practical applications of organic chemistry is described. Students were required to study a pharmaceutical or other organic compound and perform a qualitative risk assessment on the chemical. Student perceptions of the benefits of the paper were generally positive. (Contains…

  14. Acid-Base Learning Outcomes for Students in an Introductory Organic Chemistry Course

    ERIC Educational Resources Information Center

    Stoyanovich, Carlee; Gandhi, Aneri; Flynn, Alison B.

    2015-01-01

    An outcome-based approach to teaching and learning focuses on what the student demonstrably knows and can do after instruction, rather than on what the instructor teaches. This outcome-focused approach can then guide the alignment of teaching strategies, learning activities, and assessment. In organic chemistry, mastery of organic acid-base…

  15. Minimal Impact of Organic Chemistry Prerequisite on Student Performance in Introductory Biochemistry

    PubMed Central

    Cotner, Sehoya; Winkel, Amy

    2009-01-01

    Curriculum design assumes that successful completion of prerequisite courses will have a positive impact on student performance in courses that require the prerequisite. We recently had the opportunity to test this assumption concerning the relationship between completion of the organic chemistry prerequisite and performance in introductory biochemistry. We found no statistically significant differences between average biochemistry grades or grade distribution among students with or without the organic chemistry prerequisite. However, students who had not completed the organic chemistry prerequisite before biochemistry were more likely to withdraw from the course than those who had completed the prerequisite. In contrast to the lack of correlation between performance in biochemistry and completion of organic chemistry, we observed a strong, highly significant positive relationship between cumulative GPA and the biochemistry grade. Our data suggest that excluding students without organic chemistry would have less positive impact on student success in biochemistry than would providing additional support for all students who enroll in biochemistry with a cumulative GPA below 2.5. PMID:19255135

  16. Minimal impact of organic chemistry prerequisite on student performance in introductory biochemistry.

    PubMed

    Wright, Robin; Cotner, Sehoya; Winkel, Amy

    2009-01-01

    Curriculum design assumes that successful completion of prerequisite courses will have a positive impact on student performance in courses that require the prerequisite. We recently had the opportunity to test this assumption concerning the relationship between completion of the organic chemistry prerequisite and performance in introductory biochemistry. We found no statistically significant differences between average biochemistry grades or grade distribution among students with or without the organic chemistry prerequisite. However, students who had not completed the organic chemistry prerequisite before biochemistry were more likely to withdraw from the course than those who had completed the prerequisite. In contrast to the lack of correlation between performance in biochemistry and completion of organic chemistry, we observed a strong, highly significant positive relationship between cumulative GPA and the biochemistry grade. Our data suggest that excluding students without organic chemistry would have less positive impact on student success in biochemistry than would providing additional support for all students who enroll in biochemistry with a cumulative GPA below 2.5.

  17. Extraterrestrial organic chemistry: from the interstellar medium to the origins of life. Part 2: complex organic chemistry in the environment of planets and satellites.

    PubMed

    Raulin, F; Kobayashi, K

    2001-01-01

    During COSPAR'00 in Warsaw, Poland, in the frame of Sub-Commission F.3 events (Planetary Biology and Origins of Life), part of COSPAR Commission F (Life Sciences as Related to Space), and Commission B events (Space Studies of the Earth-Moon System, Planets, and Small Bodies of the Solar System) a large joint symposium (F.3.4/B0.8) was held on extraterrestrial organic chemistry. Part 2 of this symposium was devoted to complex organic chemistry in the environment of planets and satellites. The aim of this event was to cover and review new data which have been recently obtained and to give new insights on data which are expected in the near future to increase our knowledge of the complex organic chemistry occurring in several planets and satellites of the Solar System, outside the earth, and their implications for exobiology and life in the universe. The event was composed of two main parts. The first part was mainly devoted to the inner planets and Europa and the search for signatures of life or organics in those environments. The second part was related to the study of the outer solar system.

  18. Organic peroxide and OH formation in aerosol and cloud water: laboratory evidence for this aqueous chemistry

    NASA Astrophysics Data System (ADS)

    Lim, Y. B.; Turpin, B. J.

    2015-06-01

    Aqueous chemistry in atmospheric waters (e.g., cloud droplets or wet aerosols) is well accepted as an atmospheric pathway to produce secondary organic aerosol (SOAaq). Water-soluble organic compounds with small carbon numbers (C2-C3) are precursors for SOAaq and products include organic acids, organic sulfates, and high molecular weight compounds/oligomers. Fenton reactions and the uptake of gas-phase OH radicals are considered to be the major oxidant sources for aqueous organic chemistry. However, the sources and availability of oxidants in atmospheric waters are not well understood. The degree to which OH is produced in the aqueous phase affects the balance of radical and non-radical aqueous chemistry, the properties of the resulting aerosol, and likely its atmospheric behavior. This paper demonstrates organic peroxide formation during aqueous photooxidation of methylglyoxal using ultra high resolution Fourier Transform Ion Cyclotron Resonance electrospray ionization mass spectrometry (FTICR-MS). Organic peroxides are known to form through gas-phase oxidation of volatile organic compounds. They contribute secondary organic aerosol (SOA) formation directly by forming peroxyhemiacetals, and epoxides, and indirectly by enhancing gas-phase oxidation through OH recycling. We provide simulation results of organic peroxide/peroxyhemiacetal formation in clouds and wet aerosols and discuss organic peroxides as a source of condensed-phase OH radicals and as a contributor to aqueous SOA.

  19. Effects of additional nonmethane volatile organic compounds, organic nitrates, and direct emissions of oxygenated organic species on global tropospheric chemistry

    NASA Astrophysics Data System (ADS)

    Ito, Akinori; Sillman, Sanford; Penner, Joyce E.

    2007-03-01

    This work evaluates the sensitivity of tropospheric ozone and its precursors to the representation of nonmethane volatile organic compounds (NMVOCs) and organic nitrates. A global 3-D tropospheric chemistry/transport model (IMPACT) has been exercised initially using the GEOS-Chem chemical reaction mechanism. The model was then extended by adding emissions and photochemical reactions for aromatic and terpenoid hydrocarbons, and by adding explicit representation of hydroxy alkyl nitrates produced from isoprene. Emissions of methanol, phenol, acetic acid and formic acid associated with biomass burning were also added. Results show that O3 increases by 20% in most of the troposphere, peroxyacetyl nitrate (PAN) increases by 30% over much of the troposphere and OH increases by 10%. NOx (NO + NO2) decreases near source regions and increases in remote locations, reflecting increased transport of NOx away from source regions by organic nitrates. The increase in O3 was driven largely by the increased role of PAN as a transporter of NOx and by the rerelease of NOx from isoprene nitrates. The increased PAN production was associated with increases in methyl glyoxal and hydroxyacetone. Comparison with measured values show reasonable agreement for O3 and PAN, but model measurement agreement does not either improve or degrade in the extended model. The extended model shows improved agreement with measurements for methanol, acetic acid and peroxypropional nitrate (PPN). Results from the extended model were consistent with measured alkyl nitrates and glycolaldehyde, but hydroxyacetone and methyl glyoxal were overestimated. The latter suggests that the effect of the isoprene nitrates is somewhat smaller than estimated here. Although the model measurement comparison does not show specific improvements with the extended model, it provides a more complete description of tropospheric chemistry that we believe is important to include.

  20. Spatial organization of stream water discharge and chemistry in forested headwaters

    NASA Astrophysics Data System (ADS)

    Egusa, T.; Ohte, N.; Oda, T.; Suzuki, M.

    2013-12-01

    It has long been known that, in small catchments, stream water discharge and chemistry are highly variable but the variability decreases gradually with an increase in the catchment area. Wood et al. (1988) showed that model calculations of infiltration and the runoff rate became constant above a certain threshold area. They defined the threshold area as the representative elementary area (REA) and stated that above the REA only minimum knowledge of the underlying parameters is needed to explain the stream water discharge and chemistry. Subsequently, empirical studies were conducted in several catchments. These studies all verified the existence of an REA in real catchments and indicated that the REA values differed among catchments. The results also suggested that the confluence processes of stream water discharge and chemistry differed among catchments. However, it has not been clarified how the confluence processes behave and why processes differ among catchments. One of the unclear things to resolve is whether the variability of discharge and chemistry among small catchments can be regarded as randomness or if it is organized. Two previous studies examined it and reported the opposite results. Woods et al. (1995) reported that organization was apparent from their observations of specific discharge. However, Asano and Uchida (2010) stated that their results for SiO2 could be regarded as randomness. These studies targeted different observed items and different catchments. Therefore, general knowledge about organization of stream water discharge and chemistry has not been obtained. We observed spatial variability of stream water discharge and chemistry and examined the existence of spatial organization by using the statistical method. Our objective was to elucidate whether the spatial organization exists about stream water discharge and chemistry. Observations were conducted in three forested catchments in Japan. Snapshot samplings of stream water discharge and

  1. Molecular Electron Density Theory: A Modern View of Reactivity in Organic Chemistry.

    PubMed

    Domingo, Luis R

    2016-09-30

    A new theory for the study of the reactivity in Organic Chemistry, named Molecular Electron Density Theory (MEDT), is proposed herein. MEDT is based on the idea that while the electron density distribution at the ground state is responsible for physical and chemical molecular properties, as proposed by the Density Functional Theory (DFT), the capability for changes in electron density is responsible for molecular reactivity. Within MEDT, the reactivity in Organic Chemistry is studied through a rigorous quantum chemical analysis of the changes of the electron density as well as the energies associated with these changes along the reaction path in order to understand experimental outcomes. Studies performed using MEDT allow establishing a modern rationalisation and to gain insight into molecular mechanisms and reactivity in Organic Chemistry.

  2. A Research Module for the Organic Chemistry Laboratory: Multistep Synthesis of a Fluorous Dye Molecule

    PubMed Central

    2014-01-01

    A multi-session research-like module has been developed for use in the undergraduate organic teaching laboratory curriculum. Students are tasked with planning and executing the synthesis of a novel fluorous dye molecule and using it to explore a fluorous affinity chromatography separation technique, which is the first implementation of this technique in a teaching laboratory. Key elements of the project include gradually introducing students to the use of the chemical literature to facilitate their searching, as well as deliberate constraints designed to force them to think critically about reaction design and optimization in organic chemistry. The project also introduces students to some advanced laboratory practices such as Schlenk techniques, degassing of reaction mixtures, affinity chromatography, and microwave-assisted chemistry. This provides students a teaching laboratory experience that closely mirrors authentic synthetic organic chemistry practice in laboratories throughout the world. PMID:24501431

  3. A Research Module for the Organic Chemistry Laboratory: Multistep Synthesis of a Fluorous Dye Molecule.

    PubMed

    Slade, Michael C; Raker, Jeffrey R; Kobilka, Brandon; Pohl, Nicola L B

    2014-01-14

    A multi-session research-like module has been developed for use in the undergraduate organic teaching laboratory curriculum. Students are tasked with planning and executing the synthesis of a novel fluorous dye molecule and using it to explore a fluorous affinity chromatography separation technique, which is the first implementation of this technique in a teaching laboratory. Key elements of the project include gradually introducing students to the use of the chemical literature to facilitate their searching, as well as deliberate constraints designed to force them to think critically about reaction design and optimization in organic chemistry. The project also introduces students to some advanced laboratory practices such as Schlenk techniques, degassing of reaction mixtures, affinity chromatography, and microwave-assisted chemistry. This provides students a teaching laboratory experience that closely mirrors authentic synthetic organic chemistry practice in laboratories throughout the world.

  4. Molecular Images in Organic Chemistry: Assessment of Understanding in Aromaticity, Symmetry, Spectroscopy, and Shielding

    NASA Astrophysics Data System (ADS)

    Ealy, Julie B.; Hermanson, Jim

    2006-03-01

    When students take General Chemistry there are substantially fewer molecular images than they will encounter in Organic Chemistry. The molecular images Organic Chemistry students see in their textbooks are ones that use dashes and wedges to represent 2D and semi 3D views, ball and spoke, ball and wire, and structural formulas, to name just a few. They also use physical models and may also have the opportunity to work with computer generated molecular models. They are expected to understand verbal instruction connected with the images and at the same time how the verbal explanation fits with the visual image. There has been little research that combines the use of molecular images of molecules with questions that require organic chemistry students to understand concepts. This research paper addresses students' understanding of organic chemistry concepts where ball and wire and ball and spoke visual images of molecules are combined with questions related to the areas of aromaticity, symmetry, spectroscopy, and shielding. The intention is to provide a basis for assessing students' understanding.

  5. Analytical Chemistry Laboratory (ACL) procedure compendium. Volume 4, Organic methods

    SciTech Connect

    Not Available

    1993-08-01

    This interim notice covers the following: extractable organic halides in solids, total organic halides, analysis by gas chromatography/Fourier transform-infrared spectroscopy, hexadecane extracts for volatile organic compounds, GC/MS analysis of VOCs, GC/MS analysis of methanol extracts of cryogenic vapor samples, screening of semivolatile organic extracts, GPC cleanup for semivolatiles, sample preparation for GC/MS for semi-VOCs, analysis for pesticides/PCBs by GC with electron capture detection, sample preparation for pesticides/PCBs in water and soil sediment, report preparation, Florisil column cleanup for pesticide/PCBs, silica gel and acid-base partition cleanup of samples for semi-VOCs, concentrate acid wash cleanup, carbon determination in solids using Coulometrics` CO{sub 2} coulometer, determination of total carbon/total organic carbon/total inorganic carbon in radioactive liquids/soils/sludges by hot persulfate method, analysis of solids for carbonates using Coulometrics` Model 5011 coulometer, and soxhlet extraction.

  6. Design, Development, and Psychometric Analysis of a General, Organic, and Biological Chemistry Topic Inventory Based on the Identified Main Chemistry Topics Relevant to Nursing Clinical Practice

    ERIC Educational Resources Information Center

    Brown, Corina E.

    2013-01-01

    This two-stage study focused on the undergraduate nursing course that covers topics in general, organic, and biological (GOB) chemistry. In the first stage, the central objective was to identify the main concepts of GOB chemistry relevant to the clinical practice of nursing. The collection of data was based on open-ended interviews of both nursing…

  7. From polymer to small organic molecules: a tight relationship between radical chemistry and solid-phase organic synthesis.

    PubMed

    Mirizzi, Danilo; Pulici, Maurizio

    2011-04-18

    Since Gomberg's discovery of radicals as chemical entities, the interest around them has increased through the years. Nowadays, radical chemistry is used in the synthesis of 75% of all polymers, inevitably establishing a close relationship with Solid-Phase Organic Synthesis. More recently, the interest of organic chemists has shifted towards the application of usual "in-solution" radical chemistry to the solid-phase, ranging from the use of supported reagents for radical reactions, to the development of methodologies for the synthesis of small molecules or potential libraries. The aim of this review is to put in perspective radical chemistry, moving it away from its origin as a synthetic means for solid supports, to becoming a useful tool for the synthesis of small molecules.

  8. Asymmetric aminocatalysis--gold rush in organic chemistry.

    PubMed

    Melchiorre, Paolo; Marigo, Mauro; Carlone, Armando; Bartoli, Giuseppe

    2008-01-01

    Catalysis with chiral secondary amines (asymmetric aminocatalysis) has become a well-established and powerful synthetic tool for the chemo- and enantioselective functionalization of carbonyl compounds. In the last eight years alone, this field has grown at such an extraordinary pace that it is now recognized as an independent area of synthetic chemistry, where the goal is the preparation of any chiral molecule in an efficient, rapid, and stereoselective manner. This has been made possible by the impressive level of scientific competition and high quality research generated in this area. This Review describes this "Asymmetric Aminocatalysis Gold Rush" and charts the milestones in its development. As in all areas of science, progress depends on human effort.

  9. Molecular Mechanism of Acrylamide Neurotoxicity: Lessons Learned from Organic Chemistry

    PubMed Central

    Gavin, Terrence

    2012-01-01

    Background: Acrylamide (ACR) produces cumulative neurotoxicity in exposed humans and laboratory animals through a direct inhibitory effect on presynaptic function. Objectives: In this review, we delineate how knowledge of chemistry provided an unprecedented understanding of the ACR neurotoxic mechanism. We also show how application of the hard and soft, acids and bases (HSAB) theory led to the recognition that the α,β-unsaturated carbonyl structure of ACR is a soft electrophile that preferentially forms covalent bonds with soft nucleophiles. Methods: In vivo proteomic and in chemico studies demonstrated that ACR formed covalent adducts with highly nucleophilic cysteine thiolate groups located within active sites of presynaptic proteins. Additional research showed that resulting protein inactivation disrupted nerve terminal processes and impaired neurotransmission. Discussion: ACR is a type-2 alkene, a chemical class that includes structurally related electrophilic environmental pollutants (e.g., acrolein) and endogenous mediators of cellular oxidative stress (e.g., 4-hydroxy-2-nonenal). Members of this chemical family produce toxicity via a common molecular mechanism. Although individual environmental concentrations might not be toxicologically relevant, exposure to an ambient mixture of type-2 alkene pollutants could pose a significant risk to human health. Furthermore, environmentally derived type-2 alkenes might act synergistically with endogenously generated unsaturated aldehydes to amplify cellular damage and thereby accelerate human disease/injury processes that involve oxidative stress. Conclusions: These possibilities have substantial implications for environmental risk assessment and were realized through an understanding of ACR adduct chemistry. The approach delineated here can be broadly applied because many toxicants of different chemical classes are electrophiles that produce toxicity by interacting with cellular proteins. PMID:23060388

  10. An investigation of student understanding in the undergraduate organic chemistry laboratory

    NASA Astrophysics Data System (ADS)

    Grutsch, John Leo, Jr.

    Laboratory activities in organic chemistry involve a mixture of sophisticated logic and empirical observation that requires the integration of mechanistic thought, laboratory technique, and problem-solving skills. In an effort to understand how students develop the thought processes and problem-solving skills necessary for laboratory work in organic chemistry, student understanding of how the interaction between a reaction system (reactants or starting material(s), reagent(s), and/or solvent), experimental variables (pH, temperature, concentrations, etc), provides a result of interest (yield, selectivity, purity, etc.) for an experiment performed in the organic chemistry laboratory was investigated through the collection of responses to questions posed on pre-laboratory quizzes followed by in-depth interviews during which student volunteers discussed their responses along with their experiences in the laboratory. The conceptual change theory of learning which assumes new conceptions are understood, judged, acquired, or rejected in a conceptual context was used as a theoretical paradigm to examine students responses to questions posed on pre-laboratory quizzes and transcripts of the interviews with student volunteers. Students were found to not have developed a mechanistic understanding of how the interaction between a reaction system (reactants or starting material(s), reagent(s), and/or solvent), experimental variables (pH, temperature, concentrations, etc), provides a result of interest (yield, selectivity, purity, etc.) for an experiment performed in the organic chemistry laboratory. However, students' prior exposure to and understanding of chemical concepts was found to simultaneously assist and hinder in their development of a partial mechanistic understanding of how a reaction system (reactants or starting material(s), reagent(s), and/or solvent), experimental variables (pH, temperature, concentrations, etc), interact to provide a result of interest (yield

  11. An Experimental Introduction to Organic Chemistry by Way of Ethene

    ERIC Educational Resources Information Center

    Schmidt, Hans-Jurgen

    1973-01-01

    Discusses the importance of ethene (ethylene) in industry and the pipeline grid in western Europe for transporting ethene. Describes methods for investigating organic compounds in school laboratories using ethene as the key compound. (JR)

  12. Application of the organic on water reactions to prebiotic chemistry

    NASA Astrophysics Data System (ADS)

    Kolb, Vera M.

    2012-10-01

    The old view that prebiotic reactions in water are hampered by the low solubility of the organic compounds in water is now being revised due to the discoveries of the reactions "on water". These reactions occur in the heterogeneous system comprising of the organic compounds and water. Unexpectedly, such reactions are extremely efficient; they often give quantitative yields, and are accelerated in the presence of water as compared to the organic solvents. These "on water" reactions are not the same as the "in water" reactions, which occur in solution, and are thus homogenous. Examples of the "on water" reactions include Diels-Alder, Claisen, Passerini and Ugi reactions, among many others. Some of these reactions are multicomponent, but give a single product. We survey a selected number of the "on water" reactions, which have a potential prebiotic applications.

  13. Organic nitrogen chemistry during low-grade metamorphism

    USGS Publications Warehouse

    Boudou, J.-P.; Schimmelmann, A.; Ader, M.; Mastalerz, Maria; Sebilo, M.; Gengembre, L.

    2008-01-01

    Most of the organic nitrogen (Norg) on Earth is disseminated in crustal sediments and rocks in the form of fossil nitrogen-containing organic matter. The chemical speciation of fossil Norg within the overall molecular structure of organic matter changes with time and heating during burial. Progressive thermal evolution of organic matter involves phases of enhanced elimination of Norg and ultimately produces graphite containing only traces of nitrogen. Long-term chemical and thermal instability makes the chemical speciation of Norg a valuable tracer to constrain the history of sub-surface metamorphism and to shed light on the subsurface biogeochemical nitrogen cycle and its participating organic and inorganic nitrogen pools. This study documents the evolutionary path of Norg speciation, transformation and elimination before and during metamorphism and advocates the use of X-ray photoelectron spectroscopy (XPS) to monitor changes in Norg speciation as a diagnostic tool for organic metamorphism. Our multidisciplinary evidence from XPS, stable isotopes, traditional quantitative coal analyses, and other analytical approaches shows that at the metamorphic onset Norg is dominantly present as pyrrolic and pyridinic nitrogen. The relative abundance of nitrogen substituting for carbon in condensed, partially aromatic systems (where N is covalently bonded to three C atoms) increases exponentially with increasing metamorphic grade, at the expense of pyridinic and pyrrolic nitrogen. At the same time, much Norg is eliminated without significant nitrogen isotope fractionation. The apparent absence of Rayleigh-type nitrogen isotopic fractionation suggests that direct thermal loss of nitrogen from an organic matrix does not serve as a major pathway for Norg elimination. Instead, we propose that hot H, O-containing fluids or some of their components gradually penetrate into the carbonaceous matrix and eliminate Norg along a progressing reaction front, without causing nitrogen

  14. Emergence of complex chemistry on an organic monolayer.

    PubMed

    Prins, Leonard J

    2015-07-21

    In many origin-of-life scenarios, inorganic materials, such as FeS or mineral clays, play an important role owing to their ability to concentrate and select small organic molecules on their surface and facilitate their chemical transformations into new molecules. However, considering that life is made up of organic matter, at a certain stage during the evolution the role of the inorganic material must have been taken over by organic molecules. How this exactly happened is unclear, and, indeed, a big gap separates the rudimentary level of organization involving inorganic materials and the complex organization of cells, which are the building blocks of life. Over the past years, we have extensively studied the interaction of small molecules with monolayer-protected gold nanoparticles (Au NPs) for the purpose of developing innovative sensing and catalytic systems. During the course of these studies, we realized that the functional role of this system is very similar to that typically attributed to inorganic surfaces in the early stages of life, with the important being difference that the functional properties (molecular recognition, catalysis, signaling, adaptation) originate entirely from the organic monolayer rather than the inorganic support. This led us to the proposition that this system may serve as a model that illustrates how the important role of inorganic surfaces in dictating chemical processes in the early stages of life may have been taken over by organic matter. Here, we reframe our previously obtained results in the context of the origin-of-life question. The following functional roles of Au NPs will be discussed: the ability to concentrate small molecules and create different local populations, the ability to catalyze the chemical transformation of bound molecules, and, finally, the ability to install rudimentary signaling pathways and display primitive adaptive behavior. In particular, we will show that many of the functional properties of the system

  15. Supramolecular chemistry: from molecular information towards self-organization and complex matter

    NASA Astrophysics Data System (ADS)

    Lehn, Jean-Marie

    2004-03-01

    Molecular chemistry has developed a wide range of very powerful procedures for constructing ever more sophisticated molecules from atoms linked by covalent bonds. Beyond molecular chemistry lies supramolecular chemistry, which aims at developing highly complex chemical systems from components interacting via non-covalent intermolecular forces. By the appropriate manipulation of these interactions, supramolecular chemistry became progressively the chemistry of molecular information, involving the storage of information at the molecular level, in the structural features, and its retrieval, transfer, and processing at the supramolecular level, through molecular recognition processes operating via specific interactional algorithms. This has paved the way towards apprehending chemistry also as an information science. Numerous receptors capable of recognizing, i.e. selectively binding, specific substrates have been developed, based on the molecular information stored in the interacting species. Suitably functionalized receptors may perform supramolecular catalysis and selective transport processes. In combination with polymolecular organization, recognition opens ways towards the design of molecular and supramolecular devices based on functional (photoactive, electroactive, ionoactive, etc) components. A step beyond preorganization consists in the design of systems undergoing self-organization, i.e. systems capable of spontaneously generating well-defined supramolecular architectures by self-assembly from their components. Self-organization processes, directed by the molecular information stored in the components and read out at the supramolecular level through specific interactions, represent the operation of programmed chemical systems. They have been implemented for the generation of a variety of discrete functional architectures of either organic or inorganic nature. Self-organization processes also give access to advanced supramolecular materials, such as

  16. Surface chemistry of metal-organic frameworks at the liquid-solid interface.

    PubMed

    Zacher, Denise; Schmid, Rochus; Wöll, Christof; Fischer, Roland A

    2011-01-03

    Metal-organic frameworks (MOFs) are a fascinating class of novel inorganic-organic hybrid materials. They are essentially based on classic coordination chemistry and hold much promise for unique applications ranging from gas storage and separation to chemical sensing, catalysis, and drug release. The evolution of the full innovative potential of MOFs, in particular for nanotechnology and device integration, however requires a fundamental understanding of the formation process of MOFs. Also necessary is the ability to control the growth of thin MOF films and the positioning of size- and shape-selected crystals as well as MOF heterostructures on a given surface in a well-defined and oriented fashion. MOFs are solid-state materials typically formed by solvothermal reactions and their crystallization from the liquid phase involves the surface chemistry of their building blocks. This Review brings together various key aspects of the surface chemistry of MOFs.

  17. An Enzyme Kinetics Experiment for the Undergraduate Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Olsen, Robert J.; Olsen, Julie A.; Giles, Greta A.

    2010-01-01

    An experiment using [superscript 1]H NMR spectroscopy to observe the kinetics of the acylase 1-catalyzed hydrolysis of "N"-acetyl-DL-methionine has been developed for the organic laboratory. The L-enantiomer of the reactant is hydrolyzed completely in less than 2 h, and [superscript 1]H NMR spectroscopic data from a single sample can be worked up…

  18. Real World of Industrial Chemistry: Organic Chemicals from Carbon Monoxide.

    ERIC Educational Resources Information Center

    Kolb, Kenneth E.; Kolb, Doris

    1983-01-01

    Carbon Monoxide obtained from coal may serve as the source for a wide variety of organic compounds. Several of these compounds are discussed, including phosgene, benzaldehyde, methanol, formic acid and its derivatives, oxo aldehydes, acrylic acids, and others. Commercial reactions of carbon monoxide are highlighted in a table. (JN)

  19. Culturing Reality: How Organic Chemistry Graduate Students Develop into Practitioners

    ERIC Educational Resources Information Center

    Bhattacharyya, Gautam; Bodner, George M.

    2014-01-01

    Although one of the presumed aims of graduate training programs is to help students develop into practitioners of their chosen fields, very little is known about how this transition occurs. In the course of studying how graduate students learn to solve organic synthesis problems, we were able to identify some of the key factors in the epistemic…

  20. Geochemistry and Organic Chemistry on the Surface of Titan

    NASA Technical Reports Server (NTRS)

    Lunine, J. I.; Beauchamp, P.; Beauchamp, J.; Dougherty, D.; Welch, C.; Raulin, F.; Shapiro, R.; Smith, M.

    2001-01-01

    Titan's atmosphere produces a wealth of organic products from methane and nitrogen. These products, deposited on the surface in liquid and solid form, may interact with surface ices and energy sources to produce compounds of exobiological interest. Additional information is contained in the original extended abstract.

  1. Methylglyoxal in living organisms: chemistry, biochemistry, toxicology and biological implications.

    PubMed

    Kalapos, M P

    1999-11-22

    Despite the growing interest towards methylglyoxal and glyoxalases their real role in metabolic network is still obscure. In the light of developments several reviews have been published in this field mainly dealing with only a narrow segment of this research area. In this article a trial is made to present a comprehensive overview of methylglyoxal research, extending discussion from chemistry to biological implications by reviewing some important characteristics of methylglyoxal metabolism and toxicity in a wide variety of species, and emphasizing the action of methylglyoxal on energy production, free radical generation and cell killing. Special attention is paid to the discussion of alpha-oxoaldehyde production in the environment as a potential risk factor and to the possible role of this a-dicarbonyl in diseases. Concerning the interaction of methylglyoxal with biological macromolecules (DNA, RNA, proteins) an earlier review (Kalapos, Toxicology Letters, 73, 1994, 3-24) means a supplementation to this paper, thus hoping the avoidance of unnecessary bombast. The paper arrives at the conclusion that since the early stage of evolution the function of methylglyoxalase pathway has been related to carbohydrate metabolism, but its significance has been changed over the thousands of years. Namely, at the beginning of evolution methylglyoxalase path was essential for the reductive citric acid cycle as an anaplerotic route, while in the extant metabolism it concerns with the detoxification of methylglyoxal and plays some regulatory role in triose-phosphate household. As there is a tight junction between methylglyoxal and carbohydrate metabolism its pathological role in the events of the development of diabetic complications emerges in a natural manner and further progress is hoped in this field. In contrast, significant advancement cannot be expected in relation to cancer research.

  2. Green Oxidation of Menthol Enantiomers and Analysis by Circular Dichroism Spectroscopy: An Advanced Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Geiger, H. Cristina; Donohoe, James S.

    2012-01-01

    Green chemistry addresses environmental concerns associated with chemical processes and increases awareness of possible harmful effects of chemical reagents. Efficient reactions that eliminate or reduce the use of organic solvents or toxic reagents are increasingly available. A two-week experiment is reported that entails the calcium hypochlorite…

  3. Incorporating Chemical Information Instruction and Environmental Science into the First-Year Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Landolt, R. G.

    2006-01-01

    The chemical information instruction and environmental science which is incorporated into a first-year organic chemistry laboratory is presented. The students are charged with devised search strategies, conducting online searches and limiting the project scope to ocean systems. The laboratory serves to provide for search strategy development…

  4. The Implementation of a Service-Learning Component in an Organic Chemistry Laboratory Course

    ERIC Educational Resources Information Center

    Glover, Sarah R.; Sewry, Joyce D.; Bromley, Candice L.; Davies-Coleman, Michael T.; Hlengwa, Amanda

    2013-01-01

    avenues for the implementation of service-learning into their curricula. A second-year undergraduate organic chemistry laboratory experiment, in which the undergraduate students make azo dyes, can provide a vehicle for a service-learning module in which university undergraduate…

  5. Computer Based Instructional Techniques in Undergraduate Introductory Organic Chemistry: Rationale, Developmental Techniques, Programming Strategies and Evaluation.

    ERIC Educational Resources Information Center

    Culp, G. H.; And Others

    Over 100 interactive computer programs for use in general and organic chemistry at the University of Texas at Austin have been prepared. The rationale for the programs is based upon the belief that computer-assisted instruction (CAI) can improve education by, among other things, freeing teachers from routine tasks, measuring entry skills,…

  6. The Impacts of an "Organic First" Chemistry Curriculum at a Liberal Arts College

    ERIC Educational Resources Information Center

    Malinak, Steven M.; Bayline, Jennifer Logan; Brletic, Patricia A.; Harris, Mark F.; Iuliucci, Robbie J.; Leonard, Michael S.; Matsuno, Nobunaka; Pallack, Linda A.; Stringfield, Thomas W.; Sunderland, Deborah Polvani

    2014-01-01

    The chemistry department at Washington & Jefferson College implemented an "organic first" curriculum in the fall semester of 2005. Assessment data suggest that the net impact of this change for the department and associated constituencies has been positive: (i) Student outcomes have generally not been impacted by the curricular…

  7. Meaningful Understanding and Systems Thinking in Organic Chemistry: Validating Measurement and Exploring Relationships

    ERIC Educational Resources Information Center

    Vachliotis, Theodoros; Salta, Katerina; Tzougraki, Chryssa

    2014-01-01

    The purpose of this study was dual: First, to develop and validate assessment schemes for assessing 11th grade students' meaningful understanding of organic chemistry concepts, as well as their systems thinking skills in the domain. Second, to explore the relationship between the two constructs of interest based on students' performance…

  8. The Use of Solid Aluminum Heat Transfer Devices in Organic Chemistry Laboratory Instruction and Research.

    ERIC Educational Resources Information Center

    Lodwig, Siegfried N.

    1989-01-01

    Presents a practical and attractive alternative to the sand bath used in the microscale procedures developed by Mayo, Pike, and Butcher. Urges the organic chemistry teaching community to continue towards complete conversion to microscale techniques. Presents the use of aluminum devices in the microlaboratory. (MVL)

  9. The Relationship of Test Performance to ISDP Rating in Organic Chemistry Texts.

    ERIC Educational Resources Information Center

    Choi, Soo-Young; And Others

    1979-01-01

    Describes the Instructional Strategy Diagnostic Profile (ISDP)--an analytic tool that facilitates the evaluation and revision of existing instruction and the design of new instruction--and recounts its use in comparing two textbooks to determine the most appropriate for an organic chemistry course. (JEG)

  10. Adapting to Student Learning Styles: Engaging Students with Cell Phone Technology in Organic Chemistry Instruction

    ERIC Educational Resources Information Center

    Pursell, David P.

    2009-01-01

    Students of organic chemistry traditionally make 3 x 5 in. flash cards to assist learning nomenclature, structures, and reactions. Advances in educational technology have enabled flash cards to be viewed on computers, offering an endless array of drilling and feedback for students. The current generation of students is less inclined to use…

  11. Using Green Chemistry Principles as a Framework to Incorporate Research into the Organic Laboratory Curriculum

    ERIC Educational Resources Information Center

    Lee, Nancy E.; Gurney, Rich; Soltzberg, Leonard

    2014-01-01

    Despite the accepted pedagogical value of integrating research into the laboratory curriculum, this approach has not been widely adopted. The activation barrier to this change is high, especially in organic chemistry, where a large number of students are required to take this course, special glassware or setups may be needed, and dangerous…

  12. A Survey of the Practices, Procedures, and Techniques in Undergraduate Organic Chemistry Teaching Laboratories

    ERIC Educational Resources Information Center

    Martin, Christopher B.; Schmidt, Monica; Soniat, Michael

    2011-01-01

    A survey was conducted of four-year institutions that teach undergraduate organic chemistry laboratories in the United States. The data include results from over 130 schools, describes the current practices at these institutions, and discusses the statistical results such as the scale of the laboratories performed, the chemical techniques applied,…

  13. Kinetic versus Static Visuals for Facilitating College Students' Understanding of Organic Reaction Mechanisms in Chemistry

    ERIC Educational Resources Information Center

    Aldahmash, Abdulwali H.; Abraham, Michael R.

    2009-01-01

    Using animated computer-generated graphics to assist instruction has recently attracted the attention of educators and educational researchers. The specific focus of this study is to compare the influence of animated visuals with static visuals on college students' understanding of organic reaction mechanisms in chemistry. This study also focuses…

  14. Reasonable Reasoning: Multi-Variate Problem-Solving in Organic Chemistry

    ERIC Educational Resources Information Center

    Kraft, Adam; Strickland, Amanda M.; Bhattacharyya, Gautam

    2010-01-01

    In order to understand how students approach multi-variate problems, we report a study on the cues organic chemistry graduate students perceive from mechanism tasks, and the reasoning processes induced by those cues. We used the think-aloud protocol in interviews with sixteen graduate students as they worked on two types of tasks: one, in which…

  15. A Learning-Cycle-Based Organic Chemistry Laboratory Program for Students in Dietetics.

    ERIC Educational Resources Information Center

    Mueller, William J.

    1982-01-01

    The laboratory of an organic chemistry course for dietetics students is based on the learning cycle approach (exploration, invention-concept introduction, and concept application). The laboratory program is divided into four sections: lab techniques, compound types, reaction types, and reaction characteristics. (SK)

  16. Circular Dichroism Investigation of Dess-Martin Periodinane Oxidation in the Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Reed, Nicole A.; Rapp, Robert D.; Hamann, Christian S.; Artz, Pamela G.

    2005-01-01

    Dess-Martin periodinane oxidation is an experiment that provides an avenue to the introduction of Circular Dichroism (CD) spectroscopy in organic chemistry curriculum as a diagnostic tool for examination of the results of a familiar reaction, and absolute configuration. From the experiment, students increased their understanding of CD theory and…

  17. Using the Cambridge Structural Database to Teach Molecular Geometry Concepts in Organic Chemistry

    ERIC Educational Resources Information Center

    Wackerly, Jay Wm.; Janowicz, Philip A.; Ritchey, Joshua A.; Caruso, Mary M.; Elliott, Erin L.; Moore, Jeffrey S.

    2009-01-01

    This article reports a set of two homework assignments that can be used in a second-year undergraduate organic chemistry class. These assignments were designed to help reinforce concepts of molecular geometry and to give students the opportunity to use a technological database and data mining to analyze experimentally determined chemical…

  18. Results Sections in Sociology and Organic Chemistry Articles: A Genre Analysis

    ERIC Educational Resources Information Center

    Bruce, Ian

    2009-01-01

    This paper reports a genre study of the Results sections of two samples of 20 research-reporting articles from two disciplines: sociology and organic chemistry. Following the proposal of Bhatia (2004) that genre knowledge needs to be investigated from two perspectives, an "ethnographic perspective" and a "textual perspective," the Results sections…

  19. Accidental Drowning or Foul Play?: A Case Study in Organic Chemistry

    ERIC Educational Resources Information Center

    Konaklieva, Monika

    2004-01-01

    This case was developed for a sophomore organic chemistry lab to illustrate how a combination of techniques is usually required in the identification of chemical compounds. It involves a murder mystery with a forensic twist: Two bodies have been recovered from two different lakes, but because of a mix-up at the morgue, the coroner is unable to…

  20. Borohydride Reduction of Estrone: Demonstration of Diastereoselectivity in the Undergraduate Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Aditya, Animesh; Nichols, David E.; Loudon, G. Marc

    2008-01-01

    This experiment presents a guided-inquiry approach to the demonstration of diastereoselectivity in an undergraduate organic chemistry laboratory. Chiral hindered ketones such as estrone, undergo facile reduction with sodium borohydride in a highly diastereoselective manner. The diastereomeric estradiols produced in the reaction can be analyzed and…

  1. Stereoscopic Projection in Organic Chemistry: Bridging the Gap between Two and Three Dimensions.

    ERIC Educational Resources Information Center

    Rozzelle, Arlene A.; Rosenfeld, Stuart M.

    1985-01-01

    Shows how to make stereo slides of three-dimensional molecular models. The slides have been used to teach chirality, conformational isomerism, how models and two-dimensional representations embody selected aspects of structure, and fundamentals of using the specific model set required in a particular organic chemistry course. (JN)

  2. Solvent-Free Wittig Reaction: A Green Organic Chemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Leung, Sam H.; Angel, Stephen A.

    2004-01-01

    Some Wittig reactions can be carried out by grinding the reactants in a mortar with a pestle for about 20 minutes, as per investigation. A laboratory experiment involving a solvent-free Wittig reaction that can be completed in a three-hour sophomore organic chemistry laboratory class period, are developed.

  3. A Practical Introduction to Separation and Purification Techniques for the Beginning Organic Chemistry Laboratory.

    ERIC Educational Resources Information Center

    Leonard, Jack E.

    1981-01-01

    Describes a sequence of experiments developed at Texas A&M University for use in one-semester and two-semester (nonmajors) organic chemistry courses to teach a maximum number of separation and purification techniques such as distillations, recrystallization, liquid-liquid extraction, and chromatography. (SK)

  4. Decorating with Arrows: Toward the Development of Representational Competence in Organic Chemistry

    ERIC Educational Resources Information Center

    Grove, Nathaniel P.; Cooper, Melanie M.; Rush, Kelli M.

    2012-01-01

    Much effort has been expended in developing improved methods for presenting mechanistic thinking and the curved-arrow notation to organic chemistry students; however, most of these techniques are not research-based. The little research that has been conducted has mainly focused on understanding the meaning that students associate with the…

  5. Providing Students with Interdisciplinary Support to Improve Their Organic Chemistry Posters

    ERIC Educational Resources Information Center

    Widanski, Bozena; Thompson, Jo Ann; Foran-Mulcahy, Katie; Abafo, Amy

    2016-01-01

    A two-semester-long interdisciplinary support effort to improve student posters in organic chemistry lab is described. In the first semester, students' literature search report is supported by a workshop conducted by an Instruction Librarian. During the subsequent semester, a second workshop is presented by the Instruction Librarian, an English…

  6. Visualizing Molecular Chirality in the Organic Chemistry Laboratory Using Cholesteric Liquid Crystals

    ERIC Educational Resources Information Center

    Popova, Maia; Bretz, Stacey Lowery; Hartley, C. Scott

    2016-01-01

    Although stereochemistry is an important topic in second-year undergraduate organic chemistry, there are limited options for laboratory activities that allow direct visualization of macroscopic chiral phenomena. A novel, guided-inquiry experiment was developed that allows students to explore chirality in the context of cholesteric liquid crystals.…

  7. A Guided Inquiry Liquid/Liquid Extractions Laboratory for Introductory Organic Chemistry

    ERIC Educational Resources Information Center

    Raydo, Margaret L.; Church, Megan S.; Taylor, Zane W.; Taylor, Christopher E.; Danowitz, Amy M.

    2015-01-01

    A guided inquiry laboratory experiment for teaching liquid/liquid extractions to first semester undergraduate organic chemistry students is described. This laboratory is particularly useful for introductory students as the analytes that are separated are highly colored dye molecules. This allows students to track into which phase each analyte…

  8. Another Piece of the Puzzle: The Relationship between Beliefs and Practice in Higher Education Organic Chemistry

    ERIC Educational Resources Information Center

    Farre, Andrea Soledad; Lorenzo, Maria Gabriela

    2009-01-01

    An original study about beliefs, conceptions and discourse analyses of organic chemistry teachers is presented. We used Likert questionnaires and discourse analysis to examine conceptions of the nature of science, learning and teaching at university level. A case study of four female teachers with varying experience and teacher training was…

  9. Minimal Impact of Organic Chemistry Prerequisite on Student Performance in Introductory Biochemistry

    ERIC Educational Resources Information Center

    Wright, Robin; Cotner, Sehoya; Winkel, Amy

    2009-01-01

    Curriculum design assumes that successful completion of prerequisite courses will have a positive impact on student performance in courses that require the prerequisite. We recently had the opportunity to test this assumption concerning the relationship between completion of the organic chemistry prerequisite and performance in introductory…

  10. Interdisciplinary Learning for Chemical Engineering Students from Organic Chemistry Synthesis Lab to Reactor Design to Separation

    ERIC Educational Resources Information Center

    Armstrong, Matt; Comitz, Richard L.; Biaglow, Andrew; Lachance, Russ; Sloop, Joseph

    2008-01-01

    A novel approach to the Chemical Engineering curriculum sequence of courses at West Point enabled our students to experience a much more realistic design process, which more closely replicated a real world scenario. Students conduct the synthesis in the organic chemistry lab, then conduct computer modeling of the reaction with ChemCad and…

  11. Searching for Synthetic Antimicrobial Peptides: An Experiment for Organic Chemistry Students

    ERIC Educational Resources Information Center

    Vasquez, Thomas E., Jr.; Saldan~a, Cristina; Muzikar, Katy A.; Mashek, Debra; Liu, Jane M.

    2016-01-01

    This laboratory experiment provides undergraduate students enrolled in organic chemistry the opportunity to design and synthesize their own peptide, which is then tested for antimicrobial activity. After reading a primary scientific paper on antimicrobial peptides, students design and synthesize their own hexapeptide that they hypothesize will…

  12. Structure Determination of Unknown Organic Liquids Using NMR and IR Spectroscopy: A General Chemistry Laboratory

    ERIC Educational Resources Information Center

    Pavel, John T.; Hyde, Erin C.; Bruch, Martha D.

    2012-01-01

    This experiment introduced general chemistry students to the basic concepts of organic structures and to the power of spectroscopic methods for structure determination. Students employed a combination of IR and NMR spectroscopy to perform de novo structure determination of unknown alcohols, without being provided with a list of possible…

  13. A Green, Guided-Inquiry Based Electrophilic Aromatic Substitution for the Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Eby, Eric; Deal, S. Todd

    2008-01-01

    We developed an alternative electrophilic aromatic substitution reaction for the organic chemistry teaching laboratory. The experiment is an electrophilic iodination reaction of salicylamide, a popular analgesic, using environmentally friendly reagents--sodium iodide and household bleach. Further, we designed the lab as a guided-inquiry…

  14. Content-Related Interactions and Methods of Reasoning within Self-Initiated Organic Chemistry Study Groups

    ERIC Educational Resources Information Center

    Christian, Karen Jeanne

    2011-01-01

    Students often use study groups to prepare for class or exams; yet to date, we know very little about how these groups actually function. This study looked at the ways in which undergraduate organic chemistry students prepared for exams through self-initiated study groups. We sought to characterize the methods of social regulation, levels of…

  15. Microwave-Assisted Chemistry: Synthetic Applications for Rapid Assembly of Nanomaterials and Organics

    EPA Science Inventory

    The magic of microwave (MW) heating technique, termed as the Bunsen burner of the 21th Century, has emerged as valuable alternative in synthesis of organics, polymers, inorganics, and nanomaterials. Important innovations in MW-assisted chemistry now enable chemists to prepare cat...

  16. Case Study Using Online Homework in Undergraduate Organic Chemistry: Results and Student Attitudes

    ERIC Educational Resources Information Center

    Parker, Laurie L.; Loudon, G. Marc

    2013-01-01

    Managing student needs for effective learning in a large-enrollment, introductory organic chemistry course can be a challenging task. Because instructor time is at a premium, it is imperative to find resources that engage the students in active learning and provide them with feedback about their understanding of course content. Appropriately…

  17. 2005 Nobel Prize in Chemistry: Development of the Olefin Metathesis Method in Organic Synthesis

    ERIC Educational Resources Information Center

    Casey, Charles P.

    2006-01-01

    The 2005 Nobel Prize in Chemistry was awarded "for the development of the metathesis method in organic synthesis". The discoveries of the laureates provided a chemical reaction used daily in the chemical industry for the efficient and more environmentally friendly production of important pharmaceuticals, fuels, synthetic fibers, and many other…

  18. The Synthesis of a Cockroach Pheromone: An Experiment for the Second-Year Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Feist, Patty L.

    2008-01-01

    This experiment describes the synthesis of gentisyl quinone isovalerate, or blattellaquinone, a sex pheromone of the German cockroach that was isolated and identified in 2005. The synthesis is appropriate for the second semester of a second-year organic chemistry laboratory course. It can be completed in two, three-hour laboratory periods and uses…

  19. Using Biocatalysis to Integrate Organic Chemistry into a Molecular Biology Laboratory Course

    ERIC Educational Resources Information Center

    Beers, Mande; Archer, Crystal; Feske, Brent D.; Mateer, Scott C.

    2012-01-01

    Current cutting-edge biomedical investigation requires that the researcher have an operational understanding of several diverse disciplines. Biocatalysis is a field of science that operates at the crossroads of organic chemistry, biochemistry, microbiology, and molecular biology, and provides an excellent model for interdisciplinary research. We…

  20. An Introductory Organic Chemistry Review Homework Exercise: Deriving Potential Mechanisms for Glucose Ring Opening in Mutarotation

    ERIC Educational Resources Information Center

    Murdock, Margaret; Holman, R. W.; Slade, Tyler; Clark, Shelley L. D.; Rodnick, Kenneth J.

    2014-01-01

    A unique homework assignment has been designed as a review exercise to be implemented near the end of the one-year undergraduate organic chemistry sequence. Within the framework of the exercise, students derive potential mechanisms for glucose ring opening in the aqueous mutarotation process. In this endeavor, 21 general review principles are…

  1. Formalizing the First Day in an Organic Chemistry Laboratory Using a Studio-Based Approach

    ERIC Educational Resources Information Center

    Collison, Christina G.; Cody, Jeremy; Smith, Darren; Swartzenberg, Jennifer

    2015-01-01

    A novel studio-based lab module that incorporates student-centered activities was designed and implemented to introduce second-year undergraduate students to the first-semester organic chemistry laboratory. The "First Day" studio module incorporates learning objectives for the course, lab safety, and keeping a professional lab notebook.

  2. Engaging Organic Chemistry Students Using ChemDraw for iPad

    ERIC Educational Resources Information Center

    Morsch, Layne A.; Lewis, Michael

    2015-01-01

    Drawing structures, mechanisms, and syntheses is a vital part of success in organic chemistry courses. ChemDraw for iPad has been used to increase classroom experiences in the preparation of high quality chemical drawings. The embedded Flick-to-Share allows for simple, real-time exchange of ChemDraw documents. ChemDraw for iPad also allows…

  3. A Historical Analysis of the Curriculum of Organic Chemistry Using ACS Exams as Artifacts

    ERIC Educational Resources Information Center

    Raker, Jeffrey R.; Holme, Thomas A.

    2013-01-01

    Standardized examinations, such as those developed and disseminated by the ACS Examinations Institute, are artifacts of the teaching of a course and over time may provide a historical perspective on how curricula have changed and evolved. This study investigated changes in organic chemistry curricula across a 60-year period by evaluating 18 ACS…

  4. Gender Fair Efficacy of Concept Mapping Tests in Identifying Students' Difficulties in High School Organic Chemistry

    ERIC Educational Resources Information Center

    Gafoor, Kunnathodi Abdul; Shilna, V.

    2014-01-01

    In view of the perceived difficulty of organic chemistry unit for high schools students, this study examined the usefulness of concept mapping as a testing device to assess students' difficulty in the select areas. Since many tests used for identifying students misconceptions and difficulties in school subjects are observed to favour one or the…

  5. The Flipped Classroom for Teaching Organic Chemistry in Small Classes: Is It Effective?

    ERIC Educational Resources Information Center

    Fautch, Jessica M.

    2015-01-01

    The flipped classroom is a pedagogical approach that moves course content from the classroom to homework, and uses class time for engaging activities and instructor-guided problem solving. The course content in a sophomore level Organic Chemistry I course was assigned as homework using video lectures, followed by a short online quiz. In class,…

  6. A New Higher Education Curriculum in Organic Chemistry: What Questions Should Be Asked?

    ERIC Educational Resources Information Center

    Lafarge, David L.; Morge, Ludovic M.; Méheut, Martine M.

    2014-01-01

    Organic chemistry is often considered to be a difficult subject to teach and to learn, particularly as students prefer to resort to memorization alone rather than reasoning using models from chemical reactivity. Existing studies have led us to suggest principles for redefining the curriculum, ranging from its overall structure to the tasks given…

  7. Using Web-Based Video as an Assessment Tool for Student Performance in Organic Chemistry

    ERIC Educational Resources Information Center

    Tierney, John; Bodek, Matthew; Fredricks, Susan; Dudkin, Elizabeth; Kistler, Kurt

    2014-01-01

    This article shows the potential for using video responses to specific questions as part of the assessment process in an organic chemistry class. These exercises have been used with a postbaccalaureate cohort of 40 students, learning in an online environment, over a period of four years. A second cohort of 25 second-year students taking the…

  8. The Role of Spatial Ability and Strategy Preference for Spatial Problem Solving in Organic Chemistry

    ERIC Educational Resources Information Center

    Stieff, Mike; Ryu, Minjung; Dixon, Bonnie; Hegarty, Mary

    2012-01-01

    In organic chemistry, spatial reasoning is critical for reasoning about spatial relationships in three dimensions and representing spatial information in diagrams. Despite its importance, little is known about the underlying cognitive components of spatial reasoning and the strategies that students employ to solve spatial problems in organic…

  9. A Performance Enhanced Interactive Learning Workshop Model as a Supplement for Organic Chemistry Instruction

    ERIC Educational Resources Information Center

    Phillips, Karen E. S.; Grose-Fifer, Jilliam

    2011-01-01

    In this study, the authors describe a Performance Enhanced Interactive Learning (PEIL) workshop model as a supplement for organic chemistry instruction. This workshop model differs from many others in that it includes public presentations by students and other whole-class-discussion components that have not been thoroughly investigated in the…

  10. Vegetation effects on soil organic matter chemistry of aggregate fractions in a Hawaiian forest

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We examined chemical changes from live plant tissue to soil organic matter (SOM) to determine the persistence of individual plant compounds into soil aggregate fractions. We characterized the tissue chemistry of a slow- (Dicranopteris linearis) and fast-decomposing species (Cheirodendron trigynum) a...

  11. What Lies at the Heart of Good Undergraduate Teaching? A Case Study in Organic Chemistry

    ERIC Educational Resources Information Center

    Davidowitz, Bette; Rollnick, Marissa

    2011-01-01

    Teaching organic chemistry at the undergraduate level has long been regarded as challenging and students are often alienated by the mass of detail which seems to characterise the subject. In this paper we investigate the practice of an accomplished lecturer by trying to capture and portray his pedagogical content knowledge, PCK, in order to reveal…

  12. Organic Chemistry: From the Interstellar Medium to the Solar System

    NASA Technical Reports Server (NTRS)

    Sandford, Scott; Witteborn, Fred C. (Technical Monitor)

    1997-01-01

    This talk will review the various types of organic materials observed in different environments in the interstellar medium, discuss the processes by which these materials may have formed and been modified, and present the evidence supporting the contention that at least a fraction of this material survived incorporation, substantially unaltered, into our Solar System during its formation. The nature of this organic material is of direct interest to issues associated with the origin of life, both because this material represents a large fraction of the Solar System inventory of the biogenically-important elements, and because many of the compounds in this inventory have biogenic implications. Several specific examples of such molecules will be briefly discussed.

  13. Connecting biology and organic chemistry introductory laboratory courses through a collaborative research project.

    PubMed

    Boltax, Ariana L; Armanious, Stephanie; Kosinski-Collins, Melissa S; Pontrello, Jason K

    2015-01-01

    Modern research often requires collaboration of experts in fields, such as math, chemistry, biology, physics, and computer science to develop unique solutions to common problems. Traditional introductory undergraduate laboratory curricula in the sciences often do not emphasize connections possible between the various disciplines. We designed an interdisciplinary, medically relevant, project intended to help students see connections between chemistry and biology. Second term organic chemistry laboratory students designed and synthesized potential polymer inhibitors or inducers of polyglutamine protein aggregation. The use of novel target compounds added the uncertainty of scientific research to the project. Biology laboratory students then tested the novel potential pharmaceuticals in Huntington's disease model assays, using in vitro polyglutamine peptide aggregation and in vivo lethality studies in Drosophila. Students read articles from the primary literature describing the system from both chemical and biological perspectives. Assessment revealed that students emerged from both courses with a deeper understanding of the interdisciplinary nature of biology and chemistry and a heightened interest in basic research. The design of this collaborative project for introductory biology and organic chemistry labs demonstrated how the local interests and expertise at a university can be drawn from to create an effective way to integrate these introductory courses. Rather than simply presenting a series of experiments to be replicated, we hope that our efforts will inspire other scientists to think about how some aspect of authentic work can be brought into their own courses, and we also welcome additional collaborations to extend the scope of the scientific exploration.

  14. Using Tactile Learning Aids for Students with Visual Impairments in a First-Semester Organic Chemistry Course

    ERIC Educational Resources Information Center

    Poon, Thomas; Ovadia, Ronit

    2008-01-01

    This paper describes two techniques for rendering visual concepts encountered in an organic chemistry course into tactile representations for students who have low vision. The techniques--which utilize commercially available products--facilitate communication of organic chemistry between student and instructor. (Contains 1 figure, 2 tables and 1…

  15. Spicing Things up by Adding Color and Relieving Pain: The Use of "Napoleon's Buttons" in Organic Chemistry

    ERIC Educational Resources Information Center

    Bucholtz, Kevin M.

    2011-01-01

    For some students, organic chemistry can be a distant subject and unrelated to any courses they have seen in their college careers. To develop a more contextual learning experience in organic chemistry, an additional text, "Napoleon's Buttons: 17 Molecules That Changed History," by Penny Le Couteur and Jay Burreson, was incorporated as a…

  16. Structure and Evaluation of Flipped Chemistry Courses: Organic & Spectroscopy, Large and Small, First to Third Year, English and French

    ERIC Educational Resources Information Center

    Flynn, Alison B.

    2015-01-01

    Organic chemistry is a traditionally difficult subject with high failure & withdrawal rates and many areas of conceptual difficulty for students. To promote student learning and success, four undergraduate organic chemistry and spectroscopy courses at the first to third year level (17-420 students) were "flipped" in 2013-2014. In the…

  17. Using Commercially Available Techniques to Make Organic Chemistry Representations Tactile and More Accessible to Students with Blindness or Low Vision

    ERIC Educational Resources Information Center

    Supalo, Cary A.; Kennedy, Sean H.

    2014-01-01

    Organic chemistry courses can present major obstacles to access for students with blindness or low vision (BLV). In recent years, efforts have been made to represent organic chemistry concepts in tactile forms for blind students. These methodologies are described in this manuscript. Further work being done at Illinois State University is also…

  18. Perry's Scheme of Intellectual and Epistemological Development as a Framework for Describing Student Difficulties in Learning Organic Chemistry

    ERIC Educational Resources Information Center

    Grove, Nathaniel P.; Bretz, Stacey Lowery

    2010-01-01

    We have investigated student difficulties with the learning of organic chemistry. Using Perry's Model of Intellectual Development as a framework revealed that organic chemistry students who function as dualistic thinkers struggle with the complexity of the subject matter. Understanding substitution/elimination reactions and multi-step syntheses is…

  19. Azeotropic Preparation of a "C"-Phenyl "N"-Aryl Imine: An Introductory Undergraduate Organic Chemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Silverberg, Lee J.; Coyle, David J.; Cannon, Kevin C.; Mathers, Robert T.; Richards, Jeffrey A.; Tierney, John

    2016-01-01

    Imines are important in biological chemistry and as intermediates in organic synthesis. An experiment for introductory undergraduate organic chemistry is presented in which benzaldehyde was condensed with "p"-methoxyaniline in toluene to give 4-methoxy-"N"-(phenylmethylene)benzenamine. Water was removed by azeotropic…

  20. Tropospheric chemistry of internally mixed sea salt and organic particles: Surprising reactivity of NaCl with weak organic acids

    NASA Astrophysics Data System (ADS)

    Laskin, Alexander; Moffet, Ryan C.; Gilles, Mary K.; Fast, Jerome D.; Zaveri, Rahul A.; Wang, Bingbing; Nigge, Pascal; Shutthanandan, Janani

    2012-08-01

    Chemical imaging analysis of internally mixed sea salt/organic particles collected onboard the Department of Energy (DOE) G-1 aircraft during the 2010 Carbonaceous Aerosols and Radiative Effects Study (CARES) was performed using electron microscopy and X-ray spectro-microscopy. Substantial chloride depletion in aged sea salt particles was observed, which could not be explained by the known atmospheric reactivity of sea salt with inorganic nitric and sulfuric acids. We present field evidence that chloride components in sea salt particles may effectively react with organic acids releasing HCl gas to the atmosphere, leaving behind particles depleted in chloride and enriched in the corresponding organic salts. While formation of the organic salts products is not thermodynamically favored for bulk aqueous chemistry, these reactions in aerosol are driven by high volatility and evaporation of the HCl product from drying particles. These field observations were corroborated in a set of laboratory experiments where NaCl particles mixed with organic acids were found to be depleted in chloride. Combined together, the results indicate substantial chemical reactivity of sea salt particles with secondary organics that has been largely overlooked in the atmospheric aerosol chemistry. Atmospheric aging, and in particular hydration-dehydration cycles of mixed sea salt/organic particles, may result in formation of organic salts that will modify the acidity, hygroscopic, and optical properties of aged particles.

  1. Tropospheric Chemistry of Internally Mixed Sea Salt and Organic Particles: Surprising Reactivity of NaCl with Weak Organic Acids

    SciTech Connect

    Laskin, Alexander; Moffet, Ryan C.; Gilles, Marry K.; Fast, Jerome D.; Zaveri, Rahul A.; Wang, Bingbing; Nigge, P.; Shutthanandan, Janani I.

    2012-08-03

    Chemical imaging analysis of internally mixed sea salt/organic particles collected on board the Department of Energy (DOE) G-1 aircraft during the 2010 Carbonaceous Aerosols and Radiative Effects Study (CARES) was performed using electron microscopy and X-ray spectro-microscopy techniques. Substantial chloride depletion in aged sea salt particles was observed, which could not be explained by the known atmospheric reactivity of sea salt with inorganic nitric and sulfuric acids. We present field evidence that chloride components in sea salt particles may effectively react with organic acids releasing HCl gas to the atmosphere, leaving behind particles depleted in chloride and enriched in the corresponding organic salts. While formation of the organic salts products is not thermodynamically favored for bulk aqueous chemistry, these reactions in aerosol are driven by high volatility and irreversible evaporation of the HCl product from drying particles. These field observations were corroborated in a set of laboratory experiments where NaCl particles mixed with organic acids were found to be depleted in chloride. Combined together, the results indicate substantial chemical reactivity of sea salt particles with secondary organics that has been largely overlooked in the atmospheric aerosol chemistry. Atmospheric aging, and especially hydration-dehydration cycles of mixed sea salt/organic particles may result in formation of organic salts that will modify acidity, hygroscopic and optical properties of aged particles.

  2. Lead-Lead and Rubidium-Strontium In Situ Dating Using the Chemistry, Organics, and Dating EXperiment (CODEX)

    NASA Astrophysics Data System (ADS)

    Anderson, F. S.; Whitaker, T. J.; Levine, J.; Beck, S.

    2016-10-01

    We describe new results for Pb-Pb dating, and progress on laser development, for the Pb-Pb and Rb-Sr measuring, organics detecting, and elemental abundance mapping Chemistry, Organics, and Dating EXperiment (CODEX) instrument.

  3. The surface chemistry of metal-organic frameworks.

    PubMed

    McGuire, Christina V; Forgan, Ross S

    2015-03-28

    Metal-organic frameworks (MOFs) have received particular attention over the last 20 years as a result of their attractive properties offering potential applications in a number of areas. Typically, these characteristics are tuned by functionalisation of the bulk of the MOF material itself. This Feature Article focuses instead on modification of MOF particles at their surfaces only, which can also offer control over the bulk properties of the material. The differing surface modification techniques available to the synthetic chemist will be discussed, with a focus on the effect of surface modification of MOFs on their fundamental properties and application in adsorption, catalysis, drug delivery and other areas.

  4. Nobel Prize in Chemistry. Development of the Olefin Metathesis Method in Organic Synthesis

    NASA Astrophysics Data System (ADS)

    Casey, Charles P.

    2006-02-01

    The 2005 Nobel Prize in Chemistry was awarded to Yves Chauvin of the Institut Français du Pétrole, Robert H. Grubbs of CalTech, and Richard R. Schrock of MIT "for development of the metathesis method in organic synthesis". The discoveries of the laureates provided a chemical reaction now used daily in the chemical industry for the efficient and more environmentally friendly production of important pharmaceuticals, fuels, synthetic fibers, and many other products. This article tells the story of how olefin metathesis became a truly useful synthetic transformation and a triumph for mechanistic chemistry, and illustrates the importance of fundamental research. See JCE Featured Molecules .

  5. Tholins - Organic chemistry of interstellar grains and gas

    NASA Technical Reports Server (NTRS)

    Sagan, C.; Khare, B. N.

    1979-01-01

    The paper discusses tholins, defined as complex organic solids formed by the interaction of energy - for example, UV light or spark discharge - with various mixtures of cosmically abundant gases - CH4, C2H6, NH3, H2O, HCHO, and H2S. It is suggested that tholins occur in the interstellar medium and are responsible for some of the properties of the interstellar grains and gas. Additional occurrences of tholins are considered. Tholins have been produced experimentally; 50 or so pyrolytic fragments of the brown, sometimes sticky substances have been identified by gas chromatography-mass spectrometry, and the incidence of these fragments in tholins produced by different procedures is reported.

  6. Organic chemistry of Murchison meteorite: Carbon isotopic fractionation

    NASA Technical Reports Server (NTRS)

    Yuen, G. U.; Blair, N. E.; Desmarais, D. J.; Cronin, J. R.; Chang, S.

    1986-01-01

    The carbon isotopic composition of individual organic compounds of meteoritic origin remains unknown, as most reported carbon isotopic ratios are for bulk carbon or solvent extractable fractions. The researchers managed to determine the carbon isotopic ratios for individual hydrocarbons and monocarboxylic acids isolated from a Murchison sample by a freeze-thaw-ultrasonication technique. The abundances of monocarboxylic acids and saturated hydrocarbons decreased with increasing carbon number and the acids are more abundant than the hydrocarbon with the same carbon number. For both classes of compounds, the C-13 to C-12 ratios decreased with increasing carbon number in a roughly parallel manner, and each carboxylic acid exhibits a higher isotopic number than the hydrocarbon containing the same number of carbon atoms. These trends are consistent with a kinetically controlled synthesis of higher homologues for lower ones.

  7. [Exploitation of the chemistry of magnesium carbenoids and their use in organic synthesis].

    PubMed

    Satoh, Tsuyoshi

    2009-09-01

    Synthetic organic chemistry is a base of medicinal chemistry and the exploitation of new methods for carbon-carbon bond formation is of most importance in synthetic organic chemistry. Carbenes and carbenoids have long been known to be highly reactive carbon species that show a variety of unique reactivity. However, those reactive species are not fully used in organic synthesis. The reasons are as follows: one is the precursors for the generation of carbenes and carbenoids are quite limited and the other is that the reactivity of the species is too high to control. In order to solve the problem mentioned above, we used alpha-haloalkyl (or alkenyl) aryl sulfoxides as the precursors and used sulfoxide-magnesium exchange reaction for generation of much mild magnesium carbenoids. alpha-Haloalkyl (or alkenyl) aryl sulfoxides are quite easily synthesized in high overall yields. Magnesium carbenoids, cyclopropylmagnesium carbenoids, cyclobutylmagnesium carbenoids, magnesium beta-oxido carbenoids, and magnesium alkylidene carbenoids are generated at low temperature from the corresponding sulfoxides with a Grignard reagent in quantitative yields. They were found to be stable usually at below -60 degrees C for at least 30 min. The each magnesium carbenoids have their own unique reactivities and we could find many unprecedented reactions from these reactive species. Recent results for the developments of new synthetic methods based on the chemistry of magnesium carbenoids are described.

  8. Ubiquity of organic nitrates from nighttime chemistry in the European submicron aerosol

    NASA Astrophysics Data System (ADS)

    Kiendler-Scharr, A.; Mensah, A. A.; Friese, E.; Topping, D.; Nemitz, E.; Prevot, A. S. H.; ńijälä, M.; Allan, J.; Canonaco, F.; Canagaratna, M.; Carbone, S.; Crippa, M.; Dall Osto, M.; Day, D. A.; De Carlo, P.; Di Marco, C. F.; Elbern, H.; Eriksson, A.; Freney, E.; Hao, L.; Herrmann, H.; Hildebrandt, L.; Hillamo, R.; Jimenez, J. L.; Laaksonen, A.; McFiggans, G.; Mohr, C.; O'Dowd, C.; Otjes, R.; Ovadnevaite, J.; Pandis, S. N.; Poulain, L.; Schlag, P.; Sellegri, K.; Swietlicki, E.; Tiitta, P.; Vermeulen, A.; Wahner, A.; Worsnop, D.; Wu, H.-C.

    2016-07-01

    In the atmosphere nighttime removal of volatile organic compounds is initiated to a large extent by reaction with the nitrate radical (NO3) forming organic nitrates which partition between gas and particulate phase. Here we show based on particle phase measurements performed at a suburban site in the Netherlands that organic nitrates contribute substantially to particulate nitrate and organic mass. Comparisons with a chemistry transport model indicate that most of the measured particulate organic nitrates are formed by NO3 oxidation. Using aerosol composition data from three intensive observation periods at numerous measurement sites across Europe, we conclude that organic nitrates are a considerable fraction of fine particulate matter (PM1) at the continental scale. Organic nitrates represent 34% to 44% of measured submicron aerosol nitrate and are found at all urban and rural sites, implying a substantial potential of PM reduction by NOx emission control.

  9. New insights into Titan's organic chemistry in the gas and aerosol phases.

    PubMed

    Raulin, F; Coll, P; Smith, N; Benilan, Y; Bruston, P; Gazeau, M C

    1999-01-01

    Titan, the largest satellite of Saturn, with a dense atmosphere very rich in organics, and many couplings in the various parts of its "geofluid", is a reference for studying prebiotic chemistry on a planetary scale. New data have been obtained from experiments simulating this organic chemistry (gas and aerosol phases), within the right ranges of temperature and a careful avoiding of any chemical contamination. They show a very good agreement with the observational data, demonstrating for the first time the formation of all the organic species already detected in Titan atmosphere including, at last, C4N2, together with many other species not yet detected in Titan. This strongly suggests the presence of more complex organics in Titan's atmosphere and surface, including high molecular weight polyynes and cyanopolyynes. The NASA-ESA Cassini-Huygens mission has been successfully launched in October 1997. The Cassini spacecraft will reach the Saturn system in 2004 and become an orbiter around Saturn, while the Huygens probe will penetrate into Titan's atmosphere. In situ measurements, in particular from Huygens GC-MS and ACP instruments, will provide a detailed analysis of the organics present in the air, aerosols, and surface. This very ambitious mission should yield much information of crucial importance for our knowledge of the complexity of Titan's chemistry, and, more generally for the field of exobiology.

  10. 25th anniversary article: progress in chemistry and applications of functional indigos for organic electronics.

    PubMed

    Głowacki, Eric Daniel; Voss, Gundula; Sariciftci, Niyazi Serdar

    2013-12-17

    Indigo and its derivatives are dyes and pigments with a long and distinguished history in organic chemistry. Recently, applications of this 'old' structure as a functional organic building block for organic electronics applications have renewed interest in these molecules and their remarkable chemical and physical properties. Natural-origin indigos have been processed in fully bio-compatible field effect transistors, operating with ambipolar mobilities up to 0.5 cm(2) /Vs and air-stability. The synthetic derivative isoindigo has emerged as one of the most successful building-blocks for semiconducting polymers for plastic solar cells with efficiencies > 5%. Another isomer of indigo, epindolidione, has also been shown to be one of the best reported organic transistor materials in terms of mobility (∼2 cm(2) /Vs) and stability. This progress report aims to review very recent applications of indigoids in organic electronics, but especially to logically bridge together the hereto independent research directions on indigo, isoindigo, and other materials inspired by historical dye chemistry: a field which was the root of the development of modern chemistry in the first place.

  11. "No one does this for fun": Contextualization and process writing in an organic chemistry laboratory course

    NASA Astrophysics Data System (ADS)

    Gay, Andrea

    This study investigated the introduction of curriculum innovations into an introductory organic chemistry laboratory course. Pre-existing experiments in a traditional course were re-written in a broader societal context. Additionally, a new laboratory notebook methodology was introduced, using the Decision/Explanation/Observation/Inference (DEOI) format that required students to explicitly describe the purpose of procedural steps and the meanings of observations. Experts in organic chemistry, science writing, and chemistry education examined the revised curriculum and deemed it appropriate. The revised curriculum was introduced into two sections of organic chemistry laboratory at Columbia University. Field notes were taken during the course, students and teaching assistants were interviewed, and completed student laboratory reports were examined to ascertain the impact of the innovations. The contextualizations were appreciated for making the course more interesting; for lending a sense of purpose to the study of chemistry; and for aiding in students' learning. Both experts and students described a preference for more extensive connections between the experiment content and the introduced context. Generally, students preferred the DEOI method to journal-style laboratory reports believing it to be more efficient and more focused on thinking than stylistic formalities. The students claimed that the DEOI method aided their understanding of the experiments and helped scaffold their thinking, though some students thought that the method was over-structured and disliked the required pre-laboratory work. The method was used in two distinct manners; recursively writing and revising as intended and concept contemplation only after experiment completion. The recursive use may have been influenced by TA attitudes towards the revisions and seemed to engender a sense of preparedness. Students' engagement with the contextualizations and the DEOI method highlight the need for

  12. Redox chemistry and natural organic matter (NOM): Geochemists' dream, analytical chemists' nightmare

    USGS Publications Warehouse

    Macalady, Donald L.; Walton-Day, Katherine

    2011-01-01

    Natural organic matter (NOM) is an inherently complex mixture of polyfunctional organic molecules. Because of their universality and chemical reversibility, oxidation/reductions (redox) reactions of NOM have an especially interesting and important role in geochemistry. Variabilities in NOM composition and chemistry make studies of its redox chemistry particularly challenging, and details of NOM-mediated redox reactions are only partially understood. This is in large part due to the analytical difficulties associated with NOM characterization and the wide range of reagents and experimental systems used to study NOM redox reactions. This chapter provides a summary of the ongoing efforts to provide a coherent comprehension of aqueous redox chemistry involving NOM and of techniques for chemical characterization of NOM. It also describes some attempts to confirm the roles of different structural moieties in redox reactions. In addition, we discuss some of the operational parameters used to describe NOM redox capacities and redox states, and describe nomenclature of NOM redox chemistry. Several relatively facile experimental methods applicable to predictions of the NOM redox activity and redox states of NOM samples are discussed, with special attention to the proposed use of fluorescence spectroscopy to predict relevant redox characteristics of NOM samples.

  13. Chemical insights, explicit chemistry and yields of secondary organic aerosol from methylglyoxal and glyoxal

    NASA Astrophysics Data System (ADS)

    Lim, Y. B.; Tan, Y.; Turpin, B. J.

    2013-02-01

    Atmospherically abundant, volatile water soluble organic compounds formed through gas phase chemistry (e.g., glyoxal (C2), methylglyoxal (C3) and acetic acid) have great potential to form secondary organic aerosol (SOA) via aqueous chemistry in clouds, fogs and wet aerosols. This paper (1) provides chemical insights into aqueous-phase OH radical-initiated reactions leading to SOA formation from methylglyoxal and (2) uses this and a previously published glyoxal mechanism (Lim et al., 2010) to provide SOA yields for use in chemical transport models. Detailed reaction mechanisms including peroxy radical chemistry and a full kinetic model for aqueous photochemistry of acetic acid and methylglyoxal are developed and validated by comparing simulations with the experimental results from previous studies (Tan et al., 2010, 2012). This new methylglyoxal model is then combined with the previous glyoxal model (Lim et al., 2010), and is used to simulate the profiles of products and to estimate SOA yields. At cloud relevant concentrations (∼ 10-6-∼ 10-3 M; Munger et al., 1995) of glyoxal and methylglyoxal, the major photooxidation products are oxalic acid and pyruvic acid, and simulated SOA yields (by mass) are ∼ 120% for glyoxal and ∼ 80% for methylglyoxal. Oligomerization of unreacted aldehydes during droplet evaporation could enhance yields. In wet aerosols, where total dissolved organics are present at much higher concentrations (∼ 10 M), the major products are oligomers formed via organic radical-radical reactions, and simulated SOA yields (by mass) are ∼ 90% for both glyoxal and methylglyoxal.

  14. Introducing chemical biology applications to introductory organic chemistry students using series of weekly assignments.

    PubMed

    Kanin, Maralee R; Pontrello, Jason K

    2016-01-01

    Calls to bring interdisciplinary content and examples into introductory science courses have increased, yet strategies that involve course restructuring often suffer from the need for a significant faculty commitment to motivate change. Minimizing the need for dramatic course reorganization, the structure, reactivity, and chemical biology applications of classes of biological monomers and polymers have been integrated into introductory organic chemistry courses through three series of semester-long weekly assignments that explored (a) Carbohydrates and Oligosaccharides, (b) Amino Acids, Peptides, and Proteins, and (c) Nucleosides, Nucleotides, and Nucleic Acids. Comparisons of unannounced pre- and post tests revealed improved understanding of a reaction introduced in the assignments, and course examinations evaluated cumulative assignment topics. Course surveys revealed that demonstrating biologically relevant applications consistently throughout the semesters enhanced student interest in the connection between basic organic chemistry content and its application to new and unfamiliar bio-related examples. Covering basic material related to these classes of molecules outside of the classroom opened lecture time to allow the instructor to further build on information developed through the weekly assignments, teaching advanced topics and applications typically not covered in an introductory organic chemistry lecture course. Assignments were implemented as homework, either with or without accompanying discussion, in both laboratory and lecture organic courses within the context of the existing course structures.

  15. Conceptual change in an organic chemistry laboratory: A comparison of computer simulations and traditional laboratory experiments

    NASA Astrophysics Data System (ADS)

    Gaddis, Barbara A.

    2001-12-01

    This quasi-experimental research study examined the effect of computer simulations and hands-on laboratory experiments in enhancing conceptual understanding and alleviating misconceptions of organic chemistry reaction mechanisms. Subjects were sixty-nine sophomore-level organic chemistry students enrolled in four laboratory sections. Laboratory sections were stratified across instructor and randomly assigned to serve as a control or treatment laboratory. Students in the control group performed all hands-on experiments. Students in the treatment group performed hands-on experiments for the first and last part of the semester but performed computer simulations for a five-week period in the middle of the semester. Prior to treatment, groups were equivalent with respect to academic orientation, motivation, formal reasoning ability, and spatial visualization ability. Fifteen common misconceptions held by beginning organic chemistry students were identified from the Covalent Bonding and Structures Test. At the end of the semester, thirteen of these misconceptions persisted. Molecular geometry was the only category of misconceptions that significantly improved as a result of computer simulations, F(1,58) = 6.309, p = .015. No significant differential change was observed in misconceptions about bond polarity, molecular polarity, intermolecular forces, lattice structures, or the octet rule. Computer simulations were found to result in significantly greater conceptual understanding of organic chemistry reactions on two of the experiments, Stereochemistry, F(1,55) = 6.174, p = .016, and Nucleophilic Substitution, F(1,57) = 6.093, p = .017. The other three experiments, Infrared Spectroscopy, Elimination, and Oxymercuration, did not show a significant differential effect between types of laboratory experiences. No significant differences were observed on long-term retention of concepts. Overall conclusions from the study are that neither computer simulations nor hands

  16. The Discovery-Oriented Approach to Organic Chemistry. 7. Rearrangement of "trans"-Stilbene Oxide with Bismuth Trifluoromethanesulfonate and Other Metal Triflates: A Microscale Green Organic Chemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Christensen, James E.; Huddle, Matthew G.; Rogers, Jamie L.; Yung, Herbie; Mohan, Ram S.

    2008-01-01

    Although green chemistry principles are increasingly stressed in the undergraduate curriculum, there are only a few lab experiments wherein the toxicity of reagents is taken into consideration in the design of the experiment. We report a microscale green organic chemistry laboratory experiment that illustrates the utility of metal triflates,…

  17. Integration of Video-Based Demonstrations to Prepare Students for the Organic Chemistry Laboratory

    NASA Astrophysics Data System (ADS)

    Nadelson, Louis S.; Scaggs, Jonathan; Sheffield, Colin; McDougal, Owen M.

    2015-08-01

    Consistent, high-quality introductions to organic chemistry laboratory techniques effectively and efficiently support student learning in the organic chemistry laboratory. In this work, we developed and deployed a series of instructional videos to communicate core laboratory techniques and concepts. Using a quasi-experimental design, we tested the videos in five traditional laboratory experiments by integrating them with the standard pre-laboratory student preparation presentations and instructor demonstrations. We assessed the influence of the videos on student laboratory knowledge and performance, using sections of students who did not view the videos as the control. Our analysis of pre-quizzes revealed the control group had equivalent scores to the treatment group, while the post-quiz results show consistently greater learning gains for the treatment group. Additionally, the students who watched the videos as part of their pre-laboratory instruction completed their experiments in less time.

  18. Detection of Organics at Mars: How Wet Chemistry Onboard SAM Helps

    NASA Technical Reports Server (NTRS)

    Buch, A.; Freissinet, Caroline; Szopa, C.; Glavin, D.; Coll, P.; Cabane, M.; Eigenbrode, J.; Navarro-Gonzalez, R.; Coscia, D.; Teinturier, S.; Mahaffy, P.

    2013-01-01

    For the first time in the history of space exploration, a mission of interest to astrobiology could be able to analyze refractory organic compounds in the soil of Mars. Wet chemistry experiment allow organic components to be altered in such a way that improves there detection either by releasing the compounds from sample matricies or by changing the chemical structure to be amenable to analytical conditions. The latter is particular important when polar compounds are present. Sample Analysis at Mars (SAM), on the Curiosity rover of the Mars Science Laboratory mission, has onboard two wet chemistry experiments: derivatization and thermochemolysis. Here we report on the nature of the MTBSTFA derivatization experiment on SAM, the detection of MTBSTFA in initial SAM results, and the implications of this detection.

  19. Varying responses of insect herbivores to altered plant chemistry under organic and conventional treatments

    PubMed Central

    Staley, Joanna T.; Stewart-Jones, Alex; Pope, Tom W.; Wright, Denis J.; Leather, Simon R.; Hadley, Paul; Rossiter, John T.; van Emden, Helmut F.; Poppy, Guy M.

    2010-01-01

    The hypothesis that plants supplied with organic fertilizers are better defended against insect herbivores than those supplied with synthetic fertilizers was tested over two field seasons. Organic and synthetic fertilizer treatments at two nitrogen concentrations were supplied to Brassica plants, and their effects on the abundance of herbivore species and plant chemistry were assessed. The organic treatments also differed in fertilizer type: a green manure was used for the low-nitrogen treatment, while the high-nitrogen treatment contained green and animal manures. Two aphid species showed different responses to fertilizers: the Brassica specialist Brevicoryne brassicae was more abundant on organically fertilized plants, while the generalist Myzus persicae had higher populations on synthetically fertilized plants. The diamondback moth Plutella xylostella (a crucifer specialist) was more abundant on synthetically fertilized plants and preferred to oviposit on these plants. Glucosinolate concentrations were up to three times greater on plants grown in the organic treatments, while foliar nitrogen was maximized on plants under the higher of the synthetic fertilizer treatments. The varying response of herbivore species to these strong differences in plant chemistry demonstrates that hypotheses on defence in organically grown crops have over-simplified the response of phytophagous insects. PMID:19906673

  20. Varying responses of insect herbivores to altered plant chemistry under organic and conventional treatments.

    PubMed

    Staley, Joanna T; Stewart-Jones, Alex; Pope, Tom W; Wright, Denis J; Leather, Simon R; Hadley, Paul; Rossiter, John T; van Emden, Helmut F; Poppy, Guy M

    2010-03-07

    The hypothesis that plants supplied with organic fertilizers are better defended against insect herbivores than those supplied with synthetic fertilizers was tested over two field seasons. Organic and synthetic fertilizer treatments at two nitrogen concentrations were supplied to Brassica plants, and their effects on the abundance of herbivore species and plant chemistry were assessed. The organic treatments also differed in fertilizer type: a green manure was used for the low-nitrogen treatment, while the high-nitrogen treatment contained green and animal manures. Two aphid species showed different responses to fertilizers: the Brassica specialist Brevicoryne brassicae was more abundant on organically fertilized plants, while the generalist Myzus persicae had higher populations on synthetically fertilized plants. The diamondback moth Plutella xylostella (a crucifer specialist) was more abundant on synthetically fertilized plants and preferred to oviposit on these plants. Glucosinolate concentrations were up to three times greater on plants grown in the organic treatments, while foliar nitrogen was maximized on plants under the higher of the synthetic fertilizer treatments. The varying response of herbivore species to these strong differences in plant chemistry demonstrates that hypotheses on defence in organically grown crops have over-simplified the response of phytophagous insects.

  1. Substantial secondary organic aerosol formation in a coniferous forest: observations of both day- and nighttime chemistry

    NASA Astrophysics Data System (ADS)

    Lee, Alex K. Y.; Abbatt, Jonathan P. D.; Leaitch, W. Richard; Li, Shao-Meng; Sjostedt, Steve J.; Wentzell, Jeremy J. B.; Liggio, John; Macdonald, Anne Marie

    2016-06-01

    Substantial biogenic secondary organic aerosol (BSOA) formation was investigated in a coniferous forest mountain region in Whistler, British Columbia. A largely biogenic aerosol growth episode was observed, providing a unique opportunity to investigate BSOA formation chemistry in a forested environment with limited influence from anthropogenic emissions. Positive matrix factorization of aerosol mass spectrometry (AMS) measurement identified two types of BSOA (BSOA-1 and BSOA-2), which were primarily generated by gas-phase oxidation of monoterpenes and perhaps sesquiterpenes. The temporal variations of BSOA-1 and BSOA-2 can be explained by gas-particle partitioning in response to ambient temperature and the relative importance of different oxidation mechanisms between day and night. While BSOA-1 arises from gas-phase ozonolysis and nitrate radical chemistry at night, BSOA-2 is likely less volatile than BSOA-1 and consists of products formed via gas-phase oxidation by OH radical and ozone during the day. Organic nitrates produced through nitrate radical chemistry can account for 22-33 % of BSOA-1 mass at night. The mass spectra of BSOA-1 and BSOA-2 have higher values of the mass fraction of m/z 91 (f91) compared to the background organic aerosol. Using f91 to evaluate BSOA formation pathways in this unpolluted, forested region, heterogeneous oxidation of BSOA-1 is a minor production pathway of BSOA-2.

  2. A Need to Reassess Physical-Organic Curricula: A Course Enhancement Using Readily Available Quantum Chemistry Programs.

    ERIC Educational Resources Information Center

    Lipkowitz, Kenny B.

    1982-01-01

    Describes a graduate-level course in physical-organic chemistry in which students learn to solve problems using computer programs available through the Quantum Chemistry Program Exchange. Includes condensed syllabus and time line showing where various computational programs are introduced. (Author/JN)

  3. [Investigation of biologically active compounds at the Department of Organic Chemistry of University of Debrecen 1992-2009. Part III].

    PubMed

    Antus, Sándor

    2010-01-01

    The author briefly reviews the beginning of the carbohydrate chemistry in Hungary with special regard to the results achieved at the Department of Organic Chemistry of University of Debrecen and summarizes the most important synthetic and pharmaceutical results obtained in this field between 1992-2009, part III.

  4. Effectiveness of Student-Generated Video as a Teaching Tool for an Instrumental Technique in the Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Jordan, Jeremy T.; Box, Melinda C.; Eguren, Kristen E.; Parker, Thomas A.; Saraldi-Gallardo, Victoria M.; Wolfe, Michael I.; Gallardo-Williams, Maria T.

    2016-01-01

    Multimedia instruction has been shown to serve as an effective learning aid for chemistry students. In this study, the viability of student-generated video instruction for organic chemistry laboratory techniques and procedure was examined and its effectiveness compared to instruction provided by a teaching assistant (TA) was evaluated. After…

  5. Size distribution dynamics reveal particle-phase chemistry in organic aerosol formation.

    PubMed

    Shiraiwa, Manabu; Yee, Lindsay D; Schilling, Katherine A; Loza, Christine L; Craven, Jill S; Zuend, Andreas; Ziemann, Paul J; Seinfeld, John H

    2013-07-16

    Organic aerosols are ubiquitous in the atmosphere and play a central role in climate, air quality, and public health. The aerosol size distribution is key in determining its optical properties and cloud condensation nucleus activity. The dominant portion of organic aerosol is formed through gas-phase oxidation of volatile organic compounds, so-called secondary organic aerosols (SOAs). Typical experimental measurements of SOA formation include total SOA mass and atomic oxygen-to-carbon ratio. These measurements, alone, are generally insufficient to reveal the extent to which condensed-phase reactions occur in conjunction with the multigeneration gas-phase photooxidation. Combining laboratory chamber experiments and kinetic gas-particle modeling for the dodecane SOA system, here we show that the presence of particle-phase chemistry is reflected in the evolution of the SOA size distribution as well as its mass concentration. Particle-phase reactions are predicted to occur mainly at the particle surface, and the reaction products contribute more than half of the SOA mass. Chamber photooxidation with a midexperiment aldehyde injection confirms that heterogeneous reaction of aldehydes with organic hydroperoxides forming peroxyhemiacetals can lead to a large increase in SOA mass. Although experiments need to be conducted with other SOA precursor hydrocarbons, current results demonstrate coupling between particle-phase chemistry and size distribution dynamics in the formation of SOAs, thereby opening up an avenue for analysis of the SOA formation process.

  6. Organic chemistry as a language and the implications of chemical linguistics for structural and retrosynthetic analyses.

    PubMed

    Cadeddu, Andrea; Wylie, Elizabeth K; Jurczak, Janusz; Wampler-Doty, Matthew; Grzybowski, Bartosz A

    2014-07-28

    Methods of computational linguistics are used to demonstrate that a natural language such as English and organic chemistry have the same structure in terms of the frequency of, respectively, text fragments and molecular fragments. This quantitative correspondence suggests that it is possible to extend the methods of computational corpus linguistics to the analysis of organic molecules. It is shown that within organic molecules bonds that have highest information content are the ones that 1) define repeat/symmetry subunits and 2) in asymmetric molecules, define the loci of potential retrosynthetic disconnections. Linguistics-based analysis appears well-suited to the analysis of complex structural and reactivity patterns within organic molecules.

  7. Nickel-Catalyzed Suzuki–Miyaura Cross-Coupling in a Green Alcohol Solvent for an Undergraduate Organic Chemistry Laboratory

    PubMed Central

    2015-01-01

    A modern undergraduate organic chemistry laboratory experiment involving the Suzuki–Miyaura coupling is reported. Although Suzuki–Miyaura couplings typically employ palladium catalysts in environmentally harmful solvents, this experiment features the use of inexpensive nickel catalysis, in addition to a “green” alcohol solvent. The experiment employs heterocyclic substrates, which are important pharmaceutical building blocks. Thus, this laboratory procedure exposes students to a variety of contemporary topics in organic chemistry, including transition metal-catalyzed cross-couplings, green chemistry, and the importance of heterocycles in drug discovery, none of which are well represented in typical undergraduate organic chemistry curricula. The experimental protocol uses commercially available reagents and is useful in both organic and inorganic instructional laboratories. PMID:25774064

  8. Nickel-Catalyzed Suzuki-Miyaura Cross-Coupling in a Green Alcohol Solvent for an Undergraduate Organic Chemistry Laboratory.

    PubMed

    Hie, Liana; Chang, Jonah J; Garg, Neil K

    2015-03-10

    A modern undergraduate organic chemistry laboratory experiment involving the Suzuki-Miyaura coupling is reported. Although Suzuki-Miyaura couplings typically employ palladium catalysts in environmentally harmful solvents, this experiment features the use of inexpensive nickel catalysis, in addition to a "green" alcohol solvent. The experiment employs heterocyclic substrates, which are important pharmaceutical building blocks. Thus, this laboratory procedure exposes students to a variety of contemporary topics in organic chemistry, including transition metal-catalyzed cross-couplings, green chemistry, and the importance of heterocycles in drug discovery, none of which are well represented in typical undergraduate organic chemistry curricula. The experimental protocol uses commercially available reagents and is useful in both organic and inorganic instructional laboratories.

  9. Thalidomide Makes a Comeback: A Case Discussion Exercise That Integrates Biochemistry and Organic Chemistry

    NASA Astrophysics Data System (ADS)

    Bennett, Nicole; Cornely, Kathleen

    2001-06-01

    The case discussion method, which involves teaching scientific theory in a framework that students can relate to their own world, is an interdisciplinary pedagogical tool. Therefore, case study exercises can be used to integrate biochemistry with other advanced chemistry courses. The case presented here can be used at the end of a second-semester organic chemistry course or in an introductory biochemistry course. The case is a fact-based, fictional story in which an FDA official must decide whether to carry out the agency's threat to shut down several buyers clubs that import thalidomide from overseas and dispense it to their members for the treatment of AIDS. Students are required to read the body of the case, analyze data, and search for information using limited leads. Using well-considered arguments based on their research, they are asked to come to conclusions about how the element of risk involved in thalidomide distribution is assessed. They apply their knowledge of biochemistry to assess how thalidomide acts at the cellular level and they apply their knowledge of organic chemistry in writing mechanisms of thalidomide hydrolysis and in the design of thalidomide analogs. Students are assessed on their ability to work in groups, to critically analyze scientific data, and to develop public policies based on risk-benefit analysis.

  10. A Titanium–Organic Framework as an Exemplar of Combining the Chemistry of Metal– and Covalent–Organic Frameworks

    SciTech Connect

    Nguyen, Ha L.; Gándara, Felipe; Furukawa, Hiroyasu; Doan, Tan L. H.; Cordova, Kyle E.; Yaghi, Omar M.

    2016-04-06

    A crystalline material with a two-dimensional structure, termed metal–organic framework-901 (MOF-901), was prepared using a strategy that combines the chemistry of MOFs and covalent–organic frameworks (COFs). This strategy involves in situ generation of an amine-functionalized titanium oxo cluster, Ti6O6(OCH3)6(AB)6 (AB = 4-aminobenzoate), which was linked with benzene-1,4-dialdehyde using imine condensation reactions, typical of COFs. The crystal structure of MOF-901 is composed of hexagonal porous layers that are likely stacked in staggered conformation (hxl topology). This MOF represents the first example of combining metal cluster chemistry with dynamic organic covalent bond formation to give a new crystalline, extended framework of titanium metal, which is rarely used in MOFs. The incorporation of Ti(IV) units made MOF-901 useful in the photocatalyzed polymerization of methyl methacrylate (MMA). The resulting polyMMA product was obtained with a high-number-average molar mass (26 850 g mol–1) and low polydispersity index (1.6), which in many respects are better than those achieved by the commercially available photocatalyst (P-25 TiO2). Additionally, the catalyst can be isolated, reused, and recycled with no loss in performance.

  11. A Titanium-Organic Framework as an Exemplar of Combining the Chemistry of Metal- and Covalent-Organic Frameworks.

    PubMed

    Nguyen, Ha L; Gándara, Felipe; Furukawa, Hiroyasu; Doan, Tan L H; Cordova, Kyle E; Yaghi, Omar M

    2016-04-06

    A crystalline material with a two-dimensional structure, termed metal-organic framework-901 (MOF-901), was prepared using a strategy that combines the chemistry of MOFs and covalent-organic frameworks (COFs). This strategy involves in situ generation of an amine-functionalized titanium oxo cluster, Ti6O6(OCH3)6(AB)6 (AB = 4-aminobenzoate), which was linked with benzene-1,4-dialdehyde using imine condensation reactions, typical of COFs. The crystal structure of MOF-901 is composed of hexagonal porous layers that are likely stacked in staggered conformation (hxl topology). This MOF represents the first example of combining metal cluster chemistry with dynamic organic covalent bond formation to give a new crystalline, extended framework of titanium metal, which is rarely used in MOFs. The incorporation of Ti(IV) units made MOF-901 useful in the photocatalyzed polymerization of methyl methacrylate (MMA). The resulting polyMMA product was obtained with a high-number-average molar mass (26 850 g mol(-1)) and low polydispersity index (1.6), which in many respects are better than those achieved by the commercially available photocatalyst (P-25 TiO2). Additionally, the catalyst can be isolated, reused, and recycled with no loss in performance.

  12. The surface as molecular reagent: organic chemistry at the semiconductor interface

    NASA Astrophysics Data System (ADS)

    Filler, Michael A.; Bent, Stacey F.

    2003-09-01

    Methods for the incorporation of organic functionality onto semiconductor surfaces have seen immense progress in recent years. Of the multiple methods developed, the direct, covalent attachment of organic moieties is valuable because it allows for excellent control of the interfacial properties. This review article will focus on a number of synthetic strategies that have been developed to exploit the unique reactivity of group-IV surfaces under vacuum. A picture of the semiconductor surface and its reactions will be developed within the standard framework of organic chemistry with emphasis on the importance of combined experimental and theoretical approaches. Three broad areas of organic chemistry will be highlighted, including nucleophilic/electrophilic, pericyclic, and aromatic reactions. The concept of nucleophilicity and electrophilicity will be discussed within the context of dative bonding and proton transfer of amines and alcohols. Pericyclic reactions cover the [4 + 2] or Diels-Alder cycloaddition, [2 + 2] cycloaddition, dipolar, and ene reactions. Examples include the reactions of alkenes, dienes, ketones, nitriles, and related multifunctional molecules at the interface. Aromaticity and the use of directing groups to influence the distribution of surface products will be illustrated with benzene, xylene, and heteroaromatic compounds. Finally, multifunctional molecules are used to describe the competition and selectively observed among different surface reactions.

  13. The organization of an educational program for specialists in clinical chemistry by the Greek Society of Clinical Chemistry-Clinical Biochemistry.

    PubMed

    Rizos, Demetrios; Karababa, Photini; Sarandakou, Angeliki; Panagiotakis, Othon; Haliassos, Alexander; Makris, Konstantinos; Psarra, Katerina; Bairaktari, Eleni; Spyropoulou, Panagiota; Nikolou, Chara; Galiatsatos, Nikolaos; Trakas, Nikolaos; Ferderigou, Angeliki; Seferiadis, Konstantin

    2011-01-01

    In Greece, there is no officially organized training in clinical chemistry for scientists. The Greek Society of Clinical Chemistry-Clinical Biochemistry decided to organize an intensive educational program of 18 seminars on clinical chemistry content as it is described in the EC4 Syllabus. The duration of each seminar was about 6 hours and consisted of 6 to 9 lectures. At the end of each seminar there was a voluntary written examination, comprised of 24 multiple choice questions. Successful completion of the Educational program was leading to a Certificate of Competence. Two cycles of the 18 seminars were performed: 1st cycle from October 2003 to December 2005 and 2nd cycle from March 2005 to October 2007. One hundred eighty nine colleagues was the mean attendance per seminar for the seminars of the 1st cycle and 38 colleagues for the seminars of the 2nd cycle. The mean participation to the examination for each seminar was almost 80% for the 1st cycle and 68% for the 2nd cycle. More than 80% of the participants performed Good or Very good in the examination in both cycles. It is estimated that more than 40% of the scientists who practice Clinical Chemistry in Greece, participated to this educational activity. This program is now provided as an e-learning application, and it is open for all scientists who want to follow the discipline of clinical chemistry.

  14. Teaching biochemistry to medical students in Singapore--from organic chemistry to problem-based learning.

    PubMed

    Khoo, H E

    2005-07-01

    The medical faculty in the National University of Singapore started in 1905 but the Chair in Biochemistry was only established in 1927. For many years the biochemistry course consisted of the teaching of the organic chemistry of substances of physiological importance, nutrition, metabolism and hormones. In 1961, clinical biochemistry was introduced and in the 1980s, genetics and molecular biology were included. By then, most of the organic chemistry content had been removed as greater emphasis was placed on clinical correlation. Laboratory classes consisted of mock glucose tolerance tests and the measurement of various enzymes. By the 1990s, students were no longer interested in such practical classes, so a bold decision was made around 1995 to remove laboratory classes from the curriculum. Unfortunately, this meant that the medical students who might have been interested in laboratory work could no longer do such work. However, the new curriculum in 1999 gave the department an opportunity to offer a laboratory course as an elective for interested students. This new curriculum adopted an integrated approach with Genetics being taught as part of Paediatrics, and a new module (Structural and Cell Biology) comprising aspects of cell biology and biochemistry was introduced. This module is currently taught by staff from Anatomy, Physiology and Biochemistry. Some biochemistry content is now incorporated into the clinical problem scenarios of problem-based learning such as jaundice, diabetes mellitus, anorexia nervosa, etc. So the evolution of teaching biochemistry to medical students in Singapore has paralleled worldwide trends and moved from the didactic teaching of organic chemistry of biomolecules to problem-based learning using clinical cases.

  15. Teaching Catalytic Antibodies to Undergraduate Students: An Organic Chemistry Lab Experiment

    NASA Astrophysics Data System (ADS)

    Shulman, Avidor; Keinan, Ehud; Shabat, Doron; Barbas, Carlos F., III

    1999-07-01

    Only 13 years ago, few believed that antibodies could be catalytic or that any protein could be made to order to perform a catalytic task. The field has quickly matured from initial proof of concept and demonstration of fundamental enzyme-like characteristics to one in which antibodies have catalyzed an extremely broad range of organic transformations. Now that the first catalytic antibody is commercially available, it is possible to bring these novel biocatalysts into the classroom so every student can gain hands-on experience and carry out experiments on the cutting edge of scientific discovery. This lab project deals with antibody-catalyzed aldol condensations. It includes the (i) synthesis of substrate and product; (ii) HPLC characterization of the antibody-catalyzed reaction; (iii) titration of the antibody active-site; and (iv) analysis of the kinetics of the antibody-catalyzed reaction. The lab project provides training not only in biocatalysis but in a number of related aspects of chemical and biochemical research, including organic synthesis, mechanistic organic chemistry, and chemical kinetics. Students will learn the use of various experimental techniques, such as UV-vis spectroscopy and HPLC, to monitor chemical reactions and determine kinetic parameters. They will be exposed to concepts and terminology of bioorganic chemistry, such as protein structure and function, inhibition and active-site titration, and basic principles of biocatalysis.

  16. Explicit modeling of organic chemistry and secondary organic aerosol partitioning for Mexico City and its outflow plume

    SciTech Connect

    Lee-Taylor, J.; Madronich, Sasha; Aumont, B.; Baker, A.; Camredon, M.; Hodzic, Alma; Tyndall, G. S.; Apel, Eric; Zaveri, Rahul A.

    2011-12-21

    The evolution of organic aerosols (OA) in Mexico City and its outflow is investigated with the nearly explicit gas phase photochemistry model GECKO-A (Generator of Explicit Chemistry and Kinetics of Organics in the Atmosphere), wherein precursor hydrocarbons are oxidized to numerous intermediate species for which vapor pressures are computed and used to determine gas/particle partitioning in a chemical box model. Precursor emissions included observed C3-10 alkanes, alkenes, and light aromatics, as well as larger n-alkanes (up to C25) not directly observed but estimated by scaling to particulate emissions according to their volatility. Conditions were selected for comparison with observations made in March 2006 (MILAGRO). The model successfully reproduces the magnitude and diurnal shape for both primary (POA) and secondary (SOA) organic aerosols, with POA peaking in the early morning at 15-20 ug m-3, and SOA peaking at 10-15 μg m-3 during mid-day. The majority (> 75%) of the model SOA stems from the large n-alkanes, with the remainder mostly from the light aromatics. Simulated OA elemental composition reproduces observed H/C and O/C ratios reasonably well, although modeled ratios develop more slowly than observations suggest. SOA chemical composition is initially dominated by *- hydroxy ketones and nitrates from the large alkanes, with contributions from peroxy acyl nitrates and, at later times when NOx is lower, organic hydroperoxides. The simulated plume-integrated OA mass continues to increase for several days downwind despite dilution-induced particle evaporation, since oxidation chemistry leading to SOA formation remains strong. In this model, the plume SOA burden several days downwind exceeds that leaving the city by a factor of >3. These results suggest significant regional radiative impacts of SOA.

  17. From the Textbook to the Lecture: Improving Prelecture Preparation in Organic Chemistry

    NASA Astrophysics Data System (ADS)

    Collard, David M.; Girardot, Steven P.; Deutsch, Howard M.

    2002-04-01

    The yearlong sequence of introductory organic chemistry lectures was modified to encourage use of the textbook and to engage students to learn material before the lecture. Online prelecture assignments, which we have named HWebs, were used to provide structured motivation for students to read the textbook and begin learning material before they came to class. The HWebs were successful in getting students to prepare for lecture on a regular basis. A survey indicated that students felt positively about being encouraged to prepare for lecture.

  18. The Isolation of Rubber from Milkweed Leaves. An Introductory Organic Chemistry Lab

    NASA Astrophysics Data System (ADS)

    Volaric, Lisa; Hagen, John P.

    2002-01-01

    We present an introductory organic chemistry lab in which students isolate rubber from the leaves of milkweed plants (Asclepias syriaca). Students isolated rubber with a recovery of 2.4 ± 1.8% and 1.8 ± 0.7% for the microscale and macroscale procedures, respectively. Infrared spectra of their products were compared with the spectrum of synthetic rubber, cis-polyisoprene. Students tested for elasticity of their product by twisting it on a spatula and pulling; all students found some degree of elasticity.

  19. Implementing Interactive Teaching Methods for 9th Grade Organic Chemistry Classes

    NASA Astrophysics Data System (ADS)

    Traykov, Ivaylo; Galcheva, Petinka

    2017-03-01

    One of the main challenges facing the current educational system is creating conditions suitable for academic skill development that allow students to navigate and adapt to today's modern society, such as locating relevant information quickly as well as effectively utilizing innovations. We can achieve this objective by using interactive teaching methods. These methods take into account the contemporary issues and changing priorities - from the general content building for the courses to independent, student-centered cognitive activities. The propose of this paper is to present tested and proven interactive methods for Grade 9Organic Chemistry classes. These methods significantly improve the quality of teaching and the students' interest in the subject.

  20. A Fifty-Year Love Affair with Organic Chemistry (by William S. Johnson)

    NASA Astrophysics Data System (ADS)

    Kauffman, Reviewed By George B.; Kauffman, Laurie M.

    1999-12-01

    This latest volume is the 20th in Jeff Seeman's projected 22-volume series of autobiographies of 20th-century organic chemists that began publication in 1990 (Kauffman, G. B. J. Chem. Educ. 1991, 68, A21). Unfortunately, Johnson did not live to see this volume in print. Ted Bartlett and Ray Conrow reviewed the final manuscript, galleys, and page proofs; and Ted Bartlett, Paul Bartlett, John D. Roberts, and Gilbert Stork contributed an epilogue that complements Johnson's own words, adds a warm, personal final touch that he was unable to provide, and incorporates his final research into the volume. Born in New Rochelle, New York, on February 24, 1913, William Summer Johnson attended Amherst College with the aid of a scholarship and various odd jobs such as tending furnace, washing dishes, and playing saxophone in dance bands (he seriously considered becoming a professional musician). Here he became enamored with organic chemistry, which he taught as an instructor for a year after his graduation magna cum laude in 1936. He then worked with a fellowship under Louis Fieser, who sparked his interest in steroids, at Harvard University, from which he received his M.A. (1938) and Ph.D. (1940) degrees. In 1940 Johnson joined the faculty at the University of Wisconsin, where he rose through the ranks, eventually becoming Homer Adkins Professor of Chemistry (1954-60). He began the total synthesis of steroids, the main subject of his life's work, "which soon proved to be the hottest synthetic target of the time". In 1960 he accepted an invitation to become head of and to upgrade the Stanford University Chemistry Department. With faculty recruiting as his primary concern, he was able to add Carl Djerassi, Paul J. Flory, Harden M. McConnell, Henry Taube, and Eugene E. van Tamelen to the department, resulting in its spectacular rise from 15th to 5th place in the nation. He remained at Stanford for the rest of his career, serving as department head for nine years. He died at the

  1. Distinct Optical Chemistry of Dissolved Organic Matter in Urban Pond Ecosystems

    PubMed Central

    McEnroe, Nicola A.; Williams, Clayton J.; Xenopoulos, Marguerite A.; Porcal, Petr; Frost, Paul C.

    2013-01-01

    Urbanization has the potential to dramatically alter the biogeochemistry of receiving freshwater ecosystems. We examined the optical chemistry of dissolved organic matter (DOM) in forty-five urban ponds across southern Ontario, Canada to examine whether optical characteristics in these relatively new ecosystems are distinct from other freshwater systems. Dissolved organic carbon (DOC) concentrations ranged from 2 to 16 mg C L-1 across the ponds with an average value of 5.3 mg C L-1. Excitation-emission matrix (EEM) spectroscopy and parallel factor analysis (PARAFAC) modelling showed urban pond DOM to be characterized by microbial-like and, less importantly, by terrestrial derived humic-like components. The relatively transparent, non-humic DOM in urban ponds was more similar to that found in open water, lake ecosystems than to rivers or wetlands. After irradiation equivalent to 1.7 days of natural solar radiation, DOC concentrations, on average, decreased by 38% and UV absorbance decreased by 25%. Irradiation decreased the relative abundances of terrestrial humic-like components and increased protein-like aspects of the DOM pool. These findings suggest that high internal production and/or prolonged exposure to sunlight exerts a distinct and significant influence on the chemistry of urban pond DOM, which likely reduces its chemical similarity with upstream sources. These properties of urban pond DOM may alter its biogeochemical role in these relatively novel aquatic ecosystems. PMID:24348908

  2. Beyond static structures: Putting forth REMD as a tool to solve problems in computational organic chemistry

    PubMed Central

    Petraglia, Riccardo; Nicolaï, Adrien; Wodrich, Matthew D.

    2016-01-01

    Computational studies of organic systems are frequently limited to static pictures that closely align with textbook style presentations of reaction mechanisms and isomerization processes. Of course, in reality chemical systems are dynamic entities where a multitude of molecular conformations exists on incredibly complex potential energy surfaces (PES). Here, we borrow a computational technique originally conceived to be used in the context of biological simulations, together with empirical force fields, and apply it to organic chemical problems. Replica‐exchange molecular dynamics (REMD) permits thorough exploration of the PES. We combined REMD with density functional tight binding (DFTB), thereby establishing the level of accuracy necessary to analyze small molecular systems. Through the study of four prototypical problems: isomer identification, reaction mechanisms, temperature‐dependent rotational processes, and catalysis, we reveal new insights and chemistry that likely would be missed using static electronic structure computations. The REMD‐DFTB methodology at the heart of this study is powered by i‐PI, which efficiently handles the interface between the DFTB and REMD codes. © 2015 The Authors. Journal of Computational Chemistry Published by Wiley Periodicals, Inc. PMID:26228927

  3. Distinct optical chemistry of dissolved organic matter in urban pond ecosystems.

    PubMed

    McEnroe, Nicola A; Williams, Clayton J; Xenopoulos, Marguerite A; Porcal, Petr; Frost, Paul C

    2013-01-01

    Urbanization has the potential to dramatically alter the biogeochemistry of receiving freshwater ecosystems. We examined the optical chemistry of dissolved organic matter (DOM) in forty-five urban ponds across southern Ontario, Canada to examine whether optical characteristics in these relatively new ecosystems are distinct from other freshwater systems. Dissolved organic carbon (DOC) concentrations ranged from 2 to 16 mg C L(-1) across the ponds with an average value of 5.3 mg C L(-1). Excitation-emission matrix (EEM) spectroscopy and parallel factor analysis (PARAFAC) modelling showed urban pond DOM to be characterized by microbial-like and, less importantly, by terrestrial derived humic-like components. The relatively transparent, non-humic DOM in urban ponds was more similar to that found in open water, lake ecosystems than to rivers or wetlands. After irradiation equivalent to 1.7 days of natural solar radiation, DOC concentrations, on average, decreased by 38% and UV absorbance decreased by 25%. Irradiation decreased the relative abundances of terrestrial humic-like components and increased protein-like aspects of the DOM pool. These findings suggest that high internal production and/or prolonged exposure to sunlight exerts a distinct and significant influence on the chemistry of urban pond DOM, which likely reduces its chemical similarity with upstream sources. These properties of urban pond DOM may alter its biogeochemical role in these relatively novel aquatic ecosystems.

  4. Pollution Prevention Plan for the Y-12 Analytical Chemistry Organization Off-Site Union Valley Facility

    SciTech Connect

    Jackson, J. G.

    2010-03-01

    The Y-12 Analytical Chemistry Organization (ACO) Off-Site Union Valley Facility (Union Valley Facility) is managed by Babcock and Wilcox Technical Services Y-12, L.L.C. (B and W Y-12) through the Y-12 National Security Complex organization. Accordingly, the Y-12 Pollution Prevention Program encompasses the operations conducted at the Union Valley Facility. The Y-12 Program is designed to fully comply with state, federal and U.S. Department of Energy (DOE) requirements concerning waste minimization/pollution prevention as documented in the Y-12 Pollution Prevention Program Plan. The Program is formulated to reduce the generation and toxicity of all Y-12 wastes in all media, including those wastes generated by the Union Valley Facility operations. All regulatory and DOE requirements are met by the Y-12 Program Plan.

  5. Synthesis of 10-Ethyl Flavin: A Multistep Synthesis Organic Chemistry Laboratory Experiment for Upper-Division Undergraduate Students

    ERIC Educational Resources Information Center

    Sichula, Vincent A.

    2015-01-01

    A multistep synthesis of 10-ethyl flavin was developed as an organic chemistry laboratory experiment for upper-division undergraduate students. Students synthesize 10-ethyl flavin as a bright yellow solid via a five-step sequence. The experiment introduces students to various hands-on experimental organic synthetic techniques, such as column…

  6. Saccharin Derivative Synthesis via [1,3] Thermal Sigmatropic Rearrangement: A Multistep Organic Chemistry Experiment for Undergraduate Students

    ERIC Educational Resources Information Center

    Fonseca, Custódia S. C.

    2016-01-01

    Saccharin (1,2-benzisothiazole-3-one 1,1-dioxide) is an artificial sweetener used in the food industry. It is a cheap and easily available organic compound that may be used in organic chemistry laboratory classes for the synthesis of related heterocyclic compounds and as a derivatizing agent. In this work, saccharin is used as a starting material…

  7. Mechanisms before Reactions: A Mechanistic Approach to the Organic Chemistry Curriculum Based on Patterns of Electron Flow

    ERIC Educational Resources Information Center

    Flynn, Alison B.; Ogilvie, William W.

    2015-01-01

    A significant redesign of the introductory organic chemistry curriculum at the authors' institution is described. There are two aspects that differ greatly from a typical functional group approach. First, organic reaction mechanisms and the electron-pushing formalism are taught before students have learned a single reaction. The conservation of…

  8. Organic Chemistry Students' Fragmented Ideas about the Structure and Function of Nucleophiles and Electrophiles: A Concept Map Analysis

    ERIC Educational Resources Information Center

    Anzovino, Mary E.; Bretz, Stacey Lowery

    2016-01-01

    Organic chemistry students struggle with multiple aspects of reaction mechanisms and the curved arrow notation used by organic chemists. Many faculty believe that an understanding of nucleophiles and electrophiles, among other concepts, is required before students can develop fluency with the electronpushing formalism (EPF). An expert concept map…

  9. Insights Into Atmospheric Aqueous Organic Chemistry Through Controlled Experiments with Cloud Water Surrogates

    NASA Astrophysics Data System (ADS)

    Turpin, B. J.; Ramos, A.; Kirkland, J. R.; Lim, Y. B.; Seitzinger, S.

    2011-12-01

    There is considerable laboratory and field-based evidence that chemical processing in clouds and wet aerosols alters organic composition and contributes to the formation of secondary organic aerosol (SOA). Single-compound laboratory experiments have played an important role in developing aqueous-phase chemical mechanisms that aid prediction of SOA formation through multiphase chemistry. In this work we conduct similar experiments with cloud/fog water surrogates, to 1) evaluate to what extent the previously studied chemistry is observed in these more realistic atmospheric waters, and 2) to identify additional atmospherically-relevant precursors and products that require further study. We used filtered Camden and Pinelands, NJ rainwater as a surrogate for cloud water. OH radical (~10-12 M) was formed by photolysis of hydrogen peroxide and samples were analyzed in real-time by electrospray ionization mass spectroscopy (ESI-MS). Discrete samples were also analyzed by ion chromatography (IC) and ESI-MS after IC separation. All experiments were performed in duplicate. Standards of glyoxal, methylglyoxal and glycolaldehyde and their major aqueous oxidation products were also analyzed, and control experiments performed. Decreases in the ion abundance of many positive mode compounds and increases in the ion abundance of many negative mode compounds (e.g., organic acids) suggest that precursors are predominantly aldehydes, organic peroxides and/or alcohols. Real-time ESI mass spectra were consistent with the expected loss of methylglyoxal and subsequent formation of pyruvate, glyoxylate, and oxalate. New insights regarding other potential precursors and products will be provided.

  10. Synthesis of a Partially Protected Azidodeoxy Sugar. A Project Suitable for the Advanced Undergraduate Organic Chemistry Laboratory

    NASA Astrophysics Data System (ADS)

    Norris, Peter; Freeze, Scott; Gabriel, Christopher J.

    2001-01-01

    The synthetic chemistry of carbohydrates provides a wealth of possible experiments for the undergraduate organic chemistry laboratory. However, few appropriate examples have been developed to date. With this simple two-step synthesis of a partially protected azidodeoxy sugar, we demonstrate several important concepts introduced in undergraduate chemistry (alcohol activation, steric hindrance, nucleophilic substitution) while offering products that are readily amenable to analysis by high field NMR. Students are exposed to techniques such as monitoring reactions by TLC, workup of reaction mixtures, and isolation by flash chromatography. Suitable methods for analysis of products include NMR, IR, MS, and polarimetry.

  11. Organic chemistry on planetary satellites around the gas giants and implications for habitability

    NASA Astrophysics Data System (ADS)

    Coustenis, Athena

    2015-08-01

    The icy satellites of the outer solar system present a variety of chemical compositions where initial complements of ices, minerals, and elements provided during formation have been subjected to various internal and external processes. Additional material has been gained via cometary and meteoritic infall, transfer of material between satellites and magnetospheric interactions. Exchanges also occur between the surface and the interior.Organic compounds have been detected on several of our Solar System’s satellites around the gas giant planets, each with unique characteristics as to organic chemistry. Jupiter’s Europa, Ganymede and Callisto show evidence of undersurface layers of liquid water that offer potentially interesting environments for organic synthesis. Spectra obtained by Galileo’s NIMS show absorption bands indicative of C-H and C≡N organic compounds. Potential organics on the large Galilean moons include CO2, carbonic acid and different kinds of carbonates, hydrocarbons and nitriles.Saturn’s Titan is a chemical factory, where the mother molecules N2 (at about 95%), CH4 (at 1.5-5%) and H2 (at 0.1%) produce a host of hydrocarbons and nitriles. The Cassini-Huygens mission has shown Titan to be indeed very rich in organic molecules, which are formed in the upper atmosphere and then deposited on the surface. Some of these species are of prebiotic importance, such as C6H6, HC3N and HCN. Titan's surface displays unique geomorphological features while it probably overlies an internal liquid water ocean. The organic deposits, if in contact with the underground liquid water could undergo an aqueous chemistry that could replicate aspects of life’s origins. Enceladus, a smaller moon of Saturn, ejects large amounts of water and organics in the space from plumes located in its southern pole. The implied requirement for liquid water reservoirs under its surface, significantly broadens the diversity of solar system environments which could be habitable

  12. Integration of Computational and Preparative Techniques to Demonstrate Physical Organic Concepts in Synthetic Organic Chemistry: An Example Using Diels-Alder Reaction

    ERIC Educational Resources Information Center

    Palmer, David R. J.

    2004-01-01

    The Diels-Alder reaction is used as an example for showing the integration of computational and preparative techniques, which help in demonstrating the physical organic concepts in synthetic organic chemistry. These experiments show that the students should not accept the computational results without questioning them and in many Diels-Alder…

  13. Water and complex organic chemistry in the cold dark cloud Barnard 5: Observations and Models

    NASA Astrophysics Data System (ADS)

    Wirström, Eva; Charnley, Steven B.; Taquet, Vianney; Persson, Carina M.

    2015-08-01

    Studies of complex organic molecule (COM) formation have traditionally been focused on hot cores in regions of massive star formation, where chemistry is driven by the elevated temperatures - evaporating ices and allowing for endothermic reactions in the gas-phase. As more sensitive instruments have become available, the types of objects known to harbour COMs like acetaldehyde (CH3CHO), dimethyl ether (CH3OCH3), methyl formate (CH3OCHO), and ketene (CH2CO) have expanded to include low mass protostars and, recently, even pre-stellar cores. We here report on the first in a new category of objects harbouring COMs: the cold dark cloud Barnard 5 where non-thermal ice desorption induce complex organic chemistry entirely unrelated to local star-formation.Methanol, which only forms efficiently on the surfaces of dust grains, provide evidence of efficient non-thermal desorption of ices in the form of prominent emission peaks offset from protostellar activity and high density tracers in cold molecular clouds. A study with Herschel targeting such methanol emission peaks resulted in the first ever detection of gas-phase water offset from protostellar activity in a dark cloud, at the so called methanol hotspot in Barnard 5.To model the effect a transient injection of ices into the gas-phase has on the chemistry of a cold, dark cloud we have included gas-grain interactions in an existing gas-phase chemical model and connected it to a chemical reaction network updated and expanded to include the formation and destruction paths of the most common COMs. Results from this model will be presented.Ground-based follow-up studies toward the methanol hotspot in B5 have resulted in the detection of a number of COMs, including CH2CO, CH3CHO, CH3OCH3, and CH3OCHO, as well as deuterated methanol (CH2DOH). Observations have also confirmed that COM emission is extended and not localised to a core structure. The implications of these observational and theoretical studies of B5 will be discussed

  14. Oxygenated Organic Chemicals in the Pacific Troposphere: Distribution, Sources and Chemistry

    NASA Technical Reports Server (NTRS)

    Singh, Hanwant B.; Salas, L.; Chatfield, R.; Czech, E.; Fried, A.; Evans, M.; Jacob, D. J.; Blake, D.; Heikes, B.; Talbot, R.

    2003-01-01

    Airborne measurements of a large number of oxygenated organic chemicals (Oxorgs) were carried out in the Pacific troposphere (0.1-12 km) in the Spring of 2001 (Feb. 24-April 10). Specifically these measuremen ts included acetone, methylethyl ketone (MEK), methanol, ethanol, ace taldehyde, propionaldehyde, PANS, and organic nitrates. Complementary measurements of formaldehyde, organic peroxides, and tracers were al so available. Ox-orgs were abundant in the clean troposphere and were greatly enhanced in the outflow regions from Asia. Their mixing ratios were typically highest in the lower troposphere and declined toward s the upper troposphere and the lowermost stratosphere. Their total a bundance (Ox-orgs) significantly exceeded that of NMHC (C2-C8 NMHC). A comparison of these data with observations collected some seven yea rs earlier (Feb.-March, 1994), did not reveal any significant changes . Throughout the troposphere mixing ratios of Ox-orgs were strongly c orrelated with each other as well as with tracers of fossil and bioma sshiof'uel combustion. Analysis of the relative enhancement of selected Oxorgs with respect to CH3Cl and CO in twelve sampled plumes, origi nating from fires, is used to assess their primary and secondary sour ces from biomass combustion. The composition of these plumes also ind icates a large shift of reactive nitrogen into the PAN reservoir ther eby limiting ozone formation. The Harvard 3-D photochemical model, th at uses state of the art chemistry and source information, is used to compare simulated and observed mixing ratios of selected species. A 1 -D model is used to explore the chemistry of aldehydes. These results will be presented.

  15. Poster 6: Influence of traces elements in the organic chemistry of upper atmosphere of Titan

    NASA Astrophysics Data System (ADS)

    Mathe, Christophe; Carrasco, Nathalie; Trainer, Melissa G.; Gautier, Thomas; Gavilan, Lisseth; Dubois, David; Li, Xiang

    2016-06-01

    In the upper atmosphere of Titan, complex chemistry leads to the formation of organic aerosols. Since the work of Khare et al. in 1984, several experiments investigated the formation of Titan aerosols, so called tholins, in the laboratory. It has been suggested that nitrogen-containing compounds may contribute significantly to the aerosols formation process. In this study, we focused on the influence of pyridine, the simplest nitrogenous aromatic hydrocarbon, on the chemistry of Titan's atmosphere and on aerosol formation. To assess the effect of pyridine on aerosol formation chemistry, we used two different experimental setups : a capacitively coupled radio-frequency (electronic impact), and a VUV Deuterium lamp (photochemistry) in a collaboration between LATMOS (Guyancourt) and NASA-GSFC (Greenbelt), respectively. Aerosols produced with both setups were first analyzed using a FTIR-ATR (Fourier Transform Infrared spectroscopy - Attenuated Total Reflection) with a spectral range of 4000-800 cm-1 to characterize their optical properties. Next the samples were analysed using a Bruker Autoflex Speed MALDI mass spectrometer with a m/z range up to 2000 Da in order to infer their composition. Infrared spectroscopy analysis showed that tholins produced with a nitrogen-methane gas mixture (95:5) and nitrogenpyridine gas mixture (99:250ppm) present very similar spectra features. Tholins produced with a mixture of nitrogenmethane-pyridine (99:1:250ppm) do not present aliphatic CH2 or CH3 vibrational signatures. This could indicate a cyclic polymerization by a pyridine skeleton. Mass spectrometry is still in progress to confirm this.

  16. On the use of plant emitted volatile organic compounds for atmospheric chemistry simulation experiments

    NASA Astrophysics Data System (ADS)

    Kiendler-Scharr, A.; Hohaus, T.; Yu, Z.; Tillmann, R.; Kuhn, U.; Andres, S.; Kaminski, M.; Wegener, R.; Novelli, A.; Fuchs, H.; Wahner, A.

    2015-12-01

    Biogenic volatile organic compounds (BVOC) contribute to about 90% of the emitted VOC globally with isoprene being one of the most abundant BVOC (Guenther 2002). Intensive efforts in studying and understanding the impact of BVOC on atmospheric chemistry were undertaken in the recent years. However many uncertainties remain, e.g. field studies have shown that in wooded areas measured OH reactivity can often not be explained by measured BVOC and their oxidation products (e.g. Noelscher et al. 2012). This discrepancy may be explained by either a lack of understanding of BVOC sources or insufficient understanding of BVOC oxidation mechanisms. Plants emit a complex VOC mixture containing likely many compounds which have not yet been measured or identified (Goldstein and Galbally 2007). A lack of understanding BVOC sources limits bottom-up estimates of secondary products of BVOC oxidation such as SOA. Similarly, the widespread oversimplification of atmospheric chemistry in simulation experiments, using single compound or simple BVOC mixtures to study atmospheric chemistry processes limit our ability to assess air quality and climate impacts of BVOC. We will present applications of the new extension PLUS (PLant chamber Unit for Simulation) to our atmosphere simulation chamber SAPHIR. PLUS is used to produce representative BVOC mixtures from direct plant emissions. We will report on the performance and characterization of the newly developed chamber. As an exemplary application, trees typical of a Boreal forest environment were used to compare OH reactivity as directly measured by LIF to the OH reactivity calculated from BVOC measured by GC-MS and PTRMS. The comparison was performed for both, primary emissions of trees without any influence of oxidizing agents and using different oxidation schemes. For the monoterpene emitters investigated here, we show that discrepancies between measured and calculated total OH reactivity increase with increasing degree of oxidation

  17. Molecular identification of organic compounds in atmospheric complex mixtures and relationship to atmospheric chemistry and sources.

    PubMed Central

    Mazurek, Monica A

    2002-01-01

    This article describes a chemical characterization approach for complex organic compound mixtures associated with fine atmospheric particles of diameters less than 2.5 m (PM2.5). It relates molecular- and bulk-level chemical characteristics of the complex mixture to atmospheric chemistry and to emission sources. Overall, the analytical approach describes the organic complex mixtures in terms of a chemical mass balance (CMB). Here, the complex mixture is related to a bulk elemental measurement (total carbon) and is broken down systematically into functional groups and molecular compositions. The CMB and molecular-level information can be used to understand the sources of the atmospheric fine particles through conversion of chromatographic data and by incorporation into receptor-based CMB models. Once described and quantified within a mass balance framework, the chemical profiles for aerosol organic matter can be applied to existing air quality issues. Examples include understanding health effects of PM2.5 and defining and controlling key sources of anthropogenic fine particles. Overall, the organic aerosol compositional data provide chemical information needed for effective PM2.5 management. PMID:12634131

  18. Intrinsic charge trapping in organic and polymeric semiconductors: a physical chemistry perspective

    SciTech Connect

    Kaake, Loren; Barbara, Paul F.; Zhu, Xiaoyang

    2010-01-12

    We aim to understand the origins of intrinsic charge carrier traps in organic and polymeric semiconductor materials from a physical chemistry perspective. In crystalline organic semiconductors, we point out some of the inadequacies in the description of intrinsic charge traps using language and concepts developed for inorganic semiconductors. In π-conjugated polymeric semiconductors, we suggest the presence of a two-tier electronic energy landscape, a bimodal majority landscape due to two dominant structural motifs and a minority electronic energy landscape from intrinsic charged defects. The bimodal majority electronic energy landscape results from a combination of amorphous domains and microcrystalline or liquid-crystalline domains. The minority tier of the electronic density of states is comprised of deep Coulomb traps embedded in the majority electronic energy landscape. This minority electronic energy landscape may dominate transport properties at low charge carrier densities, such as those expected for organic photovoltaic devices, while the bimodal majority electronic energy landscape becomes significant at high carrier densities, that is, in organic field effect transistors.

  19. Chemistry of Mesoporous Organosilica in Nanotechnology: Molecularly Organic-Inorganic Hybridization into Frameworks.

    PubMed

    Chen, Yu; Shi, Jianlin

    2016-05-01

    Organic-inorganic hybrid materials aiming to combine the individual advantages of organic and inorganic components while overcoming their intrinsic drawbacks have shown great potential for future applications in broad fields. In particular, the integration of functional organic fragments into the framework of mesoporous silica to fabricate mesoporous organosilica materials has attracted great attention in the scientific community for decades. The development of such mesoporous organosilica materials has shifted from bulk materials to nanosized mesoporous organosilica nanoparticles (designated as MONs, in comparison with traditional mesoporous silica nanoparticles (MSNs)) and corresponding applications in nanoscience and nanotechnology. In this comprehensive review, the state-of-art progress of this important hybrid nanomaterial family is summarized, focusing on the structure/composition-performance relationship of MONs of well-defined morphology, nanostructure, and nanoparticulate dimension. The synthetic strategies and the corresponding mechanisms for the design and construction of MONs with varied morphologies, compositions, nanostructures, and functionalities are overviewed initially. Then, the following part specifically concentrates on their broad spectrum of applications in nanotechnology, mainly in nanomedicine, nanocatalysis, and nanofabrication. Finally, some critical issues, presenting challenges and the future development of MONs regarding the rational synthesis and applications in nanotechnology are summarized and discussed. It is highly expected that such a unique molecularly organic-inorganic nanohybrid family will find practical applications in nanotechnology, and promote the advances of this discipline regarding hybrid chemistry and materials.

  20. Size distribution dynamics reveal particle-phase chemistry in organic aerosol formation

    NASA Astrophysics Data System (ADS)

    Shiraiwa, M.; Yee, L. D.; Schilling, K.; Loza, C. L.; Craven, J. S.; Zuend, A.; Ziemann, P. J.; Seinfeld, J.

    2013-12-01

    Organic aerosols are ubiquitous in the atmosphere and play a central role in climate, air quality and public health. The aerosol size distribution is key in determining its optical properties and cloud condensation nucleus activity. The dominant portion of organic aerosol is formed through gas-phase oxidation of volatile organic compounds, so-called secondary organic aerosol (SOA). Typical experimental measurements of SOA formation include total SOA mass and atomic oxygen-to-carbon ratio. These measurements, alone, are generally insufficient to reveal the extent to which condensed-phase reactions occur in conjunction with the multi-generation gas-phase photooxidation. Combining laboratory chamber experiments and kinetic gas-particle modeling for the dodecane SOA system, here we show that the presence of particle-phase chemistry is reflected in the evolution of the SOA size distribution as well as its mass concentration. Particle-phase reactions are predicted to occur mainly at the particle surface and the reaction products contribute more than half of the SOA mass. Chamber photooxidation with a mid-experiment aldehyde injection confirms that heterogeneous reaction of aldehydes with organic hydroperoxides forming peroxyhemiacetals can lead to a large increase in SOA mass. The results of the current work have a number of implications for SOA models. While the dynamics of an aerosol size distribution reflects the mechanism of growth, we demonstrate here that it provides a key constraint in interpreting laboratory and ambient SOA formation. This work, although carried out specifically for the long chain alkane, dodecane, is expected to be widely applicable to other major classes of SOA precursors. SOA consists of a myriad of organic compounds containing various functional groups, which can generally undergo heterogeneous/multiphase reactions forming low-volatility products such as oligomers and other high molecular mass compounds. If particle-phase chemistry is indeed

  1. Development and analysis of educational technologies for a blended organic chemistry course

    NASA Astrophysics Data System (ADS)

    Evans, Michael James

    Blended courses incorporate elements of both face-to-face and online instruction. The extent to which blended courses are conducted online, and the proper role of the online components of blended courses, have been debated and may vary. What can be said in general, however, is that online tools for blended courses are typically culled together from a variety of sources, are often very large scale, and may present distractions for students that decrease their utility as teaching tools. Furthermore, large-scale educational technologies may not be amenable to rigorous, detailed study, limiting evaluation of their effectiveness. Small-scale educational technologies run from the instructor's own server have the potential to mitigate many of these issues. Such tools give the instructor or researcher direct access to all available data, facilitating detailed analysis of student use. Code modification is simple and rapid if errors arise, since code is stored where the instructor can easily access it. Finally, the design of a small-scale tool can target a very specific application. With these ideas in mind, this work describes several projects aimed at exploring the use of small-scale, web-based software in a blended organic chemistry course. A number of activities were developed and evaluated using the Student Assessment of Learning Gains survey, and data from the activities were analyzed using quantitative methods of statistics and social network analysis methods. Findings from this work suggest that small-scale educational technologies provide significant learning benefits for students of organic chemistry---with the important caveat that instructors must offer appropriate levels of technical and pedagogical support for students. Most notably, students reported significant learning gains from activities that included collaborative learning supported by novel online tools. For the particular context of organic chemistry, which has a unique semantic language (Lewis

  2. Chemistry of decomposition of freshwater wetland sedimentary organic material during ramped pyrolysis

    NASA Astrophysics Data System (ADS)

    Williams, E. K.; Rosenheim, B. E.

    2011-12-01

    Ramped pyrolysis methodology, such as that used in the programmed-temperature pyrolysis/combustion system (PTP/CS), improves radiocarbon analysis of geologic materials devoid of authigenic carbonate compounds and with low concentrations of extractable authochthonous organic molecules. The approach has improved sediment chronology in organic-rich sediments proximal to Antarctic ice shelves (Rosenheim et al., 2008) and constrained the carbon sequestration potential of suspended sediments in the lower Mississippi River (Roe et al., in review). Although ramped pyrolysis allows for separation of sedimentary organic material based upon relative reactivity, chemical information (i.e. chemical composition of pyrolysis products) is lost during the in-line combustion of pyrolysis products. A first order approximation of ramped pyrolysis/combustion system CO2 evolution, employing a simple Gaussian decomposition routine, has been useful (Rosenheim et al., 2008), but improvements may be possible. First, without prior compound-specific extractions, the molecular composition of sedimentary organic matter is unknown and/or unidentifiable. Second, even if determined as constituents of sedimentary organic material, many organic compounds have unknown or variable decomposition temperatures. Third, mixtures of organic compounds may result in significant chemistry within the pyrolysis reactor, prior to introduction of oxygen along the flow path. Gaussian decomposition of the reaction rate may be too simple to fully explain the combination of these factors. To relate both the radiocarbon age over different temperature intervals and the pyrolysis reaction thermograph (temperature (°C) vs. CO2 evolved (μmol)) obtained from PTP/CS to chemical composition of sedimentary organic material, we present a modeling framework developed based upon the ramped pyrolysis decomposition of simple mixtures of organic compounds (i.e. cellulose, lignin, plant fatty acids, etc.) often found in sedimentary

  3. Anatomy of a cluster IDP. Part 2: Noble gas abundances, trace element geochemistry, isotopic abundances, and trace organic chemistry of several fragments from L2008#5

    NASA Technical Reports Server (NTRS)

    Thomas, K. L.; Clemett, S. J.; Flynn, G. J.; Keller, L. P.; Mckay, David S.; Messenger, S.; Nier, A. O.; Schlutter, D. J.; Sutton, S. R.; Walker, R. M.

    1994-01-01

    The topics discussed include the following: noble gas content and release temperatures; trace element abundances; heating summary of cluster fragments; isotopic measurements; and trace organic chemistry.

  4. Integrating medicinal chemistry, organic/combinatorial chemistry, and computational chemistry for the discovery of selective estrogen receptor modulators with Forecaster, a novel platform for drug discovery.

    PubMed

    Therrien, Eric; Englebienne, Pablo; Arrowsmith, Andrew G; Mendoza-Sanchez, Rodrigo; Corbeil, Christopher R; Weill, Nathanael; Campagna-Slater, Valérie; Moitessier, Nicolas

    2012-01-23

    As part of a large medicinal chemistry program, we wish to develop novel selective estrogen receptor modulators (SERMs) as potential breast cancer treatments using a combination of experimental and computational approaches. However, one of the remaining difficulties nowadays is to fully integrate computational (i.e., virtual, theoretical) and medicinal (i.e., experimental, intuitive) chemistry to take advantage of the full potential of both. For this purpose, we have developed a Web-based platform, Forecaster, and a number of programs (e.g., Prepare, React, Select) with the aim of combining computational chemistry and medicinal chemistry expertise to facilitate drug discovery and development and more specifically to integrate synthesis into computer-aided drug design. In our quest for potent SERMs, this platform was used to build virtual combinatorial libraries, filter and extract a highly diverse library from the NCI database, and dock them to the estrogen receptor (ER), with all of these steps being fully automated by computational chemists for use by medicinal chemists. As a result, virtual screening of a diverse library seeded with active compounds followed by a search for analogs yielded an enrichment factor of 129, with 98% of the seeded active compounds recovered, while the screening of a designed virtual combinatorial library including known actives yielded an area under the receiver operating characteristic (AU-ROC) of 0.78. The lead optimization proved less successful, further demonstrating the challenge to simulate structure activity relationship studies.

  5. Synthesis of Organic Matter of Prebiotic Chemistry at the Protoplanetary Disc

    NASA Astrophysics Data System (ADS)

    Snytnikov, Valeriy; Stoynovskaya, Olga; Rudina, Nina

    We have carried out scanning electron microscopic examination of CM carbonaceous chondrites meteorites Migey, Murchison, Staroe Boriskino aged more than 4.56 billion years (about 50 million years from the beginning of the formation of the Solar system). Our study confirmed the conclusion of Rozanov, Hoover and other researchers about the presence of microfossils of bacterial origin in the matrix of all these meteorites. Since the time of the Solar system formation is 60 - 100 million years, the primary biocenosis emerged in the protoplanetary disc of the Solar system before meteorites or simultaneously with them. It means that prebiological processes and RNA world appeared even earlier in the circumsolar protoplanetary disc. Most likely, this appearance of prebiotic chemistry takes place nowday in massive and medium-massive discs of the observed young stellar objects (YSO) class 0 and I. The timescale of the transition from chemical to biological evolution took less than 50 million years for the Solar system. Further evolution of individual biocenosis in a protoplanetary disc associated with varying physico-chemical conditions during the formation of the Solar system bodies. Biocenosis on these bodies could remove or develop under the influence of many cosmic factors and geological processes in the case of Earth. To complete the primary biosphere formation in short evolution time - millions of years - requires highly efficient chemical syntheses. In industrial chemistry for the efficient synthesis of ammonia, hydrogen cyanide, methanol and other organic species, that are the precursors to obtain prebiotic compounds, catalytic reactors of high pressure are used. Thus (1) necessary amount of the proper catalyst in (2) high pressure areas of the disc can trigger these intense syntheses. The disc contains the solids with the size from nanoparticle to pebble. Iron and magnesium is catalytically active ingredient for such solids. The puzzle is a way to provide hydrogen

  6. The Organic Chemistry of Volcanoes: Case Studies at Cerro Negro, Nicaragua and Oldoinyo Lengai, Tanzania

    NASA Astrophysics Data System (ADS)

    Teague, A. J.; Seward, T. M.; Gize, A. P.; Hall, T.

    2005-12-01

    Though it has long been known that volcanoes emit organic compounds within their fumarolic gases, it is only in recent years that a concerted attempt has been made to catalogue and quantify the species and fluxes. Two general lines of interest dominate this study. Firstly, volcanic gases represent some of the most likely environments in which the precursor molecules necessary for the origin of life were synthesised. The existence of an active, abiotic, organic chemistry in such settings today is fundamental to our understanding of the early Earth. Secondly, the presence of halogenated organic compounds is of interest to the atmospheric sciences, particularly with respect to their ozone depleting potential. It is clear that natural sources of halocarbons must exist, and though current natural fluxes are low with respect to the anthropogenic signature, volcanogenic halocarbons may have proved to be significant during the eruption of supervolcanoes and continental flood basalts. In this study, gases were collected from fumaroles in the craters of two, very different, active volcanoes. Cerro Negro, a young basaltic cinder cone belonging to the Central American Volcanic Belt, could be defined as a typical subduction zone volcano. Gases were collected from Cerro Negro during March 2003 and 2004 from a single fumarole discharging close to the crater floor. In contrast, Oldoinyo Lengai is the world's only active carbonatite volcano and represents the most extreme case of alkali volcanism in the East African Rift system. Fieldwork was conducted in the northern summit crater of Lengai over 8 days in October 2003. In this period, the volcano was in near continuous eruption and gases were sampled from two fumaroles situated within 20m of the eruptive centre, though measured gas temperatures were low at around 195°C. Organic compounds were collected using a variety of activated carbon, molecular sieve type adsorbents, packed into glass cartridges. The water and acid matrix of

  7. Detecting Complex Organic Compounds Using the SAM Wet Chemistry Experiment on Mars

    NASA Astrophysics Data System (ADS)

    Freissinet, C.; Buch, A.; Glavin, D. P.; Brault, A.; Eigenbrode, J. L.; Kashyap, S.; Martin, M. G.; Miller, K.; Mahaffy, P. R.; Team, M.

    2013-12-01

    The search for organic molecules on Mars can provide important first clues of abiotic chemistry and/or extinct or extant biota on the planet. Gas Chromatography Mass Spectrometry (GC-MS) is currently the most relevant space-compatible analytical tool for the detection of organic compounds. Nevertheless, GC separation is intrinsically restricted to volatile molecules, and many molecules of astrobiological interest are chromatographically refractory or polar. To analyze these organics such as amino acids, nucleobases and carboxylic acids in the Martian regolith, an additional derivatization step is required to transform them into volatile derivatives that are amenable to GC analysis. As part of the Sample Analysis at Mars (SAM) experiment onboard Mars Science Laboratory (MSL) Curiosity rover, a single-step protocol of extraction and chemical derivatization with the silylating reagent N-methyl-N-(tert-butyldimethylsilyl)-trifluoroacetamide (MTBSTFA) has been developed to reach a wide range of astrobiology-relevant refractory organic molecules (Mahaffy et al. 2012; Stalport et al. 2012). Seven cups in the SAM instrument are devoted to MTBSTFA derivatization. However, this chemical reaction adds a protective silyl group in place of each labile hydrogen, which makes the molecule non-identifiable in common mass spectra libraries. Therefore, we have created an extended library of mass spectra of MTBSTFA derivatized compounds of interest, considering their potential occurrence in Mars soils. We then looked specifically for MTBSTFA derivatized compounds using the existing and the newly created library, in various Mars analog soils. To enable a more accurate interpretation of the in situ derivatization GC-MS results that will be obtained by SAM, the lab experiments were performed as close as possible to the SAM flight instrument experimental conditions. Our first derivatization experiments display promising results, the laboratory system permitting an extraction and detection

  8. Distributed Pore Chemistry in Porous Organic Polymers in Tissue Culture Flasks

    NASA Technical Reports Server (NTRS)

    Koontz, Steven L. (Inventor)

    1999-01-01

    A method for making a biocompatible polymer article using a uniform atomic oxygen treatment is disclose. The substrate may be subsequently optionally grated with a compatibilizing compound. Compatibilizing compounds may include proteins, phosphorylcholine groups, platelet adhesion preventing polymers, albumin adhesion promoters, and the like. The compatibilized substrate may also have a living cell layer adhered thereto. The atomic oxygen is preferably produced by a flowing afterglow microwave discharge, wherein the substrate resides in a sidearm out of the plasma. Also, methods for culturing cells for various purposes using the various membranes are disclosed as well. Also disclosed are porous organic polymers having a distributed pore chemistry (DPC) comprising hydrophilic and hydrophobic regions, and a method for making the DPC by exposing the polymer to atomic oxygen wherein the rate of hydrophilization is greater than the rate of mass loss.

  9. Ionic Liquids Beyond Simple Solvents: Glimpses at the State of the Art in Organic Chemistry.

    PubMed

    Kuchenbuch, Andrea; Giernoth, Ralf

    2015-12-01

    Within the last 25 years ionic liquids have written a tremendous success story, which is documented in a nearly uncountable amount of original research papers, reviews, and numerous applications in research and industry. These days, ionic liquids can be considered as a mature class of compounds for many different applications. Frequently, they are used as neoteric solvents for chemical tansformations, and the number of reviews on this field of research is huge. In this focused review, though, we are trying to evaluate the state of the art of ionic liquid chemistry beyond using them simply as solvents for chemical transformations. It is not meant to be a comprehensive overview on the topic; the choice of emphasis and examples rather refects the authors' personal view on the field. We are especially highlighting fields in which we believe the most fundamental developments within the next five years will take place: biomass processing, (chiral) ionic liquids from natural sources, biotransformations, and organic synthesis.

  10. Assessment of Organic Chemistry Students' Knowledge of Resonance-Related Structures.

    PubMed

    Betancourt-Pérez, Rosa; Olivera, Luis Javier; Rodríguez, Julio E

    2010-01-01

    This study examines how well second-year nonmajor organic chemistry students are learning to draw, interpret, and understand resonance-related structures. Students were tested seven times throughout an academic year using a set of four tasks that reflected their understanding of what these structures represent and how they relate to each other. Statistical analysis was used to validate the tests, to investigate whether the tasks were mastered, and to examine possible correlations between the tasks and between each task and students' grades in the course. These data were also analyzed to determine which tasks were deemed most difficult and to identify the most common errors associated with each task. This study seeks to raise consciousness of areas that prove to be most difficult for students and that could be limiting their mastery of the resonance concept.

  11. Assessment of Organic Chemistry Students’ Knowledge of Resonance-Related Structures

    PubMed Central

    Betancourt-Pérez, Rosa; Olivera, Luis Javier; Rodríguez, Julio E.

    2010-01-01

    This study examines how well second-year nonmajor organic chemistry students are learning to draw, interpret, and understand resonance-related structures. Students were tested seven times throughout an academic year using a set of four tasks that reflected their understanding of what these structures represent and how they relate to each other. Statistical analysis was used to validate the tests, to investigate whether the tasks were mastered, and to examine possible correlations between the tasks and between each task and students’ grades in the course. These data were also analyzed to determine which tasks were deemed most difficult and to identify the most common errors associated with each task. This study seeks to raise consciousness of areas that prove to be most difficult for students and that could be limiting their mastery of the resonance concept. PMID:28163327

  12. Organic chemistry and immunochemical strategies in the design of potent carbohydrate-based vaccines.

    PubMed

    Roy, René; Shiao, Tze Chieh

    2011-01-01

    A brief overview of carbohydrate antigens processing and uptakes involved in the adaptive immune system is highlighted. To counter balance the poor immunogenicity and T-cell independent characteristics of carbohydrate antigens, chemists have developed original hybrid molecules aimed at targeting specific competent immune cell receptors. Amongst several potential vaccine candidates dedicated against diseases, this short report will focused on those most advance and state of the art organic chemistry involved therein. One case has led to the first example of a commercial vaccine entirely prepared from a synthetic carbohydrate antigen against infections caused by the Gram-negative bacteria Haemophilus influenza type b responsible for pneumonia and acute bacterial meningitis in infants. Other commendable examples will illustrate the immunochemical strategies engaged in the development of anticancer carbohydrate-based vaccines.

  13. My maize and blue brick road to physical organic chemistry in materials

    PubMed Central

    2016-01-01

    Summary Similar to Dorothy’s journey along the yellow brick road in The Wizard of Oz, this perspective carves out the path I took from my early childhood fascinations with science through my independent career at the University of Michigan (maize and blue). The influential research projects and mentors are highlighted, including some fortuitous experimental results that drew me into the field of supramolecular chemistry, specifically, and organic materials, broadly. My research group’s efforts toward designing new sensors based on small molecule gelators are described. In particular, I highlight how our design strategy has evolved as we learn more about molecular gelators. This perspective concludes with some predictions about where molecular gels, as well as my personal and professional life, are headed. PMID:26977181

  14. My maize and blue brick road to physical organic chemistry in materials.

    PubMed

    McNeil, Anne J

    2016-01-01

    Similar to Dorothy's journey along the yellow brick road in The Wizard of Oz, this perspective carves out the path I took from my early childhood fascinations with science through my independent career at the University of Michigan (maize and blue). The influential research projects and mentors are highlighted, including some fortuitous experimental results that drew me into the field of supramolecular chemistry, specifically, and organic materials, broadly. My research group's efforts toward designing new sensors based on small molecule gelators are described. In particular, I highlight how our design strategy has evolved as we learn more about molecular gelators. This perspective concludes with some predictions about where molecular gels, as well as my personal and professional life, are headed.

  15. Computational organic chemistry: bridging theory and experiment in establishing the mechanisms of chemical reactions.

    PubMed

    Cheng, Gui-Juan; Zhang, Xinhao; Chung, Lung Wa; Xu, Liping; Wu, Yun-Dong

    2015-02-11

    Understanding the mechanisms of chemical reactions, especially catalysis, has been an important and active area of computational organic chemistry, and close collaborations between experimentalists and theorists represent a growing trend. This Perspective provides examples of such productive collaborations. The understanding of various reaction mechanisms and the insight gained from these studies are emphasized. The applications of various experimental techniques in elucidation of reaction details as well as the development of various computational techniques to meet the demand of emerging synthetic methods, e.g., C-H activation, organocatalysis, and single electron transfer, are presented along with some conventional developments of mechanistic aspects. Examples of applications are selected to demonstrate the advantages and limitations of these techniques. Some challenges in the mechanistic studies and predictions of reactions are also analyzed.

  16. Final Report. IUT No. B560420 with UC Berkeley. Organic Chemistry at High Pressures &Temperatures

    SciTech Connect

    Montgomery, W; Crowhurst, J C; Zaug, J M; Jeanloz, R

    2007-03-20

    We have successfully completed the research outlined in our proposal: Organic Chemistry at High Pressures and Temperatures. We have experimentally determined a phase diagram which documents the phases and reaction regimes of cyanuric acid , H{sub 3}C{sub 3}N{sub 3}O{sub 3} (1,3,5-triazine-2,4,6-trione), from 300 - 750 K and 0 - 8.1 GPa. We utilized a comparatively new technique to study thin samples of cyanuric acid in the diamond anvil cell in order to collect ambient temperature, high pressure FTIR and Raman data as well as the high-pressure, high-temperature data used in the phase diagram. These experiments made use of the CMLS High-pressure lab's diamond anvil facilities as well as the FTIR and Raman systems.

  17. Global distribution and surface activity of macromolecules in offline simulations of marine organic chemistry

    DOE PAGES

    Ogunro, Oluwaseun O.; Burrows, Susannah M.; Elliott, Scott; ...

    2015-10-13

    Here, organic macromolecules constitute high percentage components of remote sea spray. They enter the atmosphere through adsorption onto bubbles followed by bursting at the ocean surface, and go on to influence the chemistry of the fine mode aerosol. We present a global estimate of mixed-layer organic macromolecular distributions, driven by offline marine systems model output. The approach permits estimation of oceanic concentrations and bubble film surface coverages for several classes of organic compound. Mixed layer levels are computed from the output of a global ocean biogeochemistry model by relating the macromolecules to standard biogeochemical tracers. Steady state is assumed formore » labile forms, and for longer-lived components we rely on ratios to existing transported variables. Adsorption is then represented through conventional Langmuir isotherms, with equilibria deduced from laboratory analogs. Open water concentrations locally exceed one micromolar carbon for the total of protein, polysaccharide and refractory heteropolycondensate. The shorter-lived lipids remain confined to regions of strong biological activity. Results are evaluated against available measurements for all compound types, and agreement is generally quite reasonable. Global distributions are further estimated for both fractional coverage of bubble films at the air-water interface and the two-dimensional concentration excess. Overall, we show that macromolecular mapping provides a novel tool for the comprehension of oceanic surfactant distributions. Results may prove useful in planning field experiments and assessing the potential response of surface chemical behaviors to global change.« less

  18. Global distribution and surface activity of macromolecules in offline simulations of marine organic chemistry

    SciTech Connect

    Ogunro, Oluwaseun O.; Burrows, Susannah M.; Elliott, Scott; Frossard, Amanda A.; Hoffman, Forrest M.; Letscher, Robert T.; Moore, J. Keith; Russell, Lynn M.; Wang, Shanlin; Wingenter, Oliver W.

    2015-10-13

    Here, organic macromolecules constitute high percentage components of remote sea spray. They enter the atmosphere through adsorption onto bubbles followed by bursting at the ocean surface, and go on to influence the chemistry of the fine mode aerosol. We present a global estimate of mixed-layer organic macromolecular distributions, driven by offline marine systems model output. The approach permits estimation of oceanic concentrations and bubble film surface coverages for several classes of organic compound. Mixed layer levels are computed from the output of a global ocean biogeochemistry model by relating the macromolecules to standard biogeochemical tracers. Steady state is assumed for labile forms, and for longer-lived components we rely on ratios to existing transported variables. Adsorption is then represented through conventional Langmuir isotherms, with equilibria deduced from laboratory analogs. Open water concentrations locally exceed one micromolar carbon for the total of protein, polysaccharide and refractory heteropolycondensate. The shorter-lived lipids remain confined to regions of strong biological activity. Results are evaluated against available measurements for all compound types, and agreement is generally quite reasonable. Global distributions are further estimated for both fractional coverage of bubble films at the air-water interface and the two-dimensional concentration excess. Overall, we show that macromolecular mapping provides a novel tool for the comprehension of oceanic surfactant distributions. Results may prove useful in planning field experiments and assessing the potential response of surface chemical behaviors to global change.

  19. Effect of Organic Coatings, Humidity and Aerosol Acidity on Multiphase Chemistry of Isoprene Epoxydiols

    SciTech Connect

    Riva, Matthieu; Bell, David M.; Hansen, Anne-Maria Kaldal; Drozd, Greg T.; Zhang, Zhenfa; Gold, Avram; Imre, Dan; Surratt, Jason D.; Glasius, Marianne; Zelenyuk, Alla

    2016-06-07

    Multiphase chemistry of isomeric isoprene epoxydiols (IEPOX) has been shown to be the dominant source of isoprene-derived secondary organic aerosol (SOA). Recent studies have reported particles composed of ammonium bisulfate (ABS) mixed with model organics exhibit slower rates of IEPOX uptake. In the present study, we investigate the effect of atmospherically-relevant organic coatings of α-pinene (AP) SOA on the reactive uptake of trans-β-IEPOX onto ABS particles under different conditions and coating thicknesses. Single particle mass spectrometry was used to characterize in real-time particle size, shape, density, and quantitative composition before and after reaction with IEPOX. We find that IEPOX uptake by pure sulfate particles is a volume-controlled process, which results in particles with uniform concentration of IEPOX-derived SOA across a wide range of sizes. Aerosol acidity was shown to enhance IEPOX-derived SOA formation, consistent with recent studies. The presence of water has a weaker impact on IEPOX-derived SOA yield, but significantly enhanced formation of 2-methyltetrols, consistent with offline filter analysis. In contrast, IEPOX uptake by ABS particles coated by AP-derived SOA is strongly dependent on particle size and composition. IEPOX uptake occurred only when weight fraction of AP-derived SOA dropped below 50 %, effectively limiting IEPOX uptake to larger particles.

  20. Chemistry Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1981

    1981-01-01

    Describes 13 activities, experiments and demonstrations, including the preparation of iron (III) chloride, simple alpha-helix model, investigating camping gas, redox reactions of some organic compounds, a liquid crystal thermometer, and the oxidation number concept in organic chemistry. (JN)

  1. Human development VIII: a theory of "deep" quantum chemistry and cell consciousness: quantum chemistry controls genes and biochemistry to give cells and higher organisms consciousness and complex behavior.

    PubMed

    Ventegodt, Søren; Hermansen, Tyge Dahl; Flensborg-Madsen, Trine; Nielsen, Maj Lyck; Merrick, Joav

    2006-11-14

    Deep quantum chemistry is a theory of deeply structured quantum fields carrying the biological information of the cell, making it able to remember, intend, represent the inner and outer world for comparison, understand what it "sees", and make choices on its structure, form, behavior and division. We suggest that deep quantum chemistry gives the cell consciousness and all the qualities and abilities related to consciousness. We use geometric symbolism, which is a pre-mathematical and philosophical approach to problems that cannot yet be handled mathematically. Using Occam's razor we have started with the simplest model that works; we presume this to be a many-dimensional, spiral fractal. We suggest that all the electrons of the large biological molecules' orbitals make one huge "cell-orbital", which is structured according to the spiral fractal nature of quantum fields. Consciousness of single cells, multi cellular structures as e.g. organs, multi-cellular organisms and multi-individual colonies (like ants) and human societies can thus be explained by deep quantum chemistry. When biochemical activity is strictly controlled by the quantum-mechanical super-orbital of the cell, this orbital can deliver energetic quanta as biological information, distributed through many fractal levels of the cell to guide form and behavior of an individual single or a multi-cellular organism. The top level of information is the consciousness of the cell or organism, which controls all the biochemical processes. By this speculative work inspired by Penrose and Hameroff we hope to inspire other researchers to formulate more strict and mathematically correct hypothesis on the complex and coherence nature of matter, life and consciousness.

  2. Organic geochemistry and pore water chemistry of sediments from Mangrove Lake, Bermuda

    USGS Publications Warehouse

    Hatcher, P.G.; Simoneit, B.R.T.; MacKenzie, F.T.; Neumann, A.C.; Thorstenson, D.C.; Gerchakov, S.M.

    1982-01-01

    Mangrove Lake, Bermuda, is a small coastal, brackish-water lake that has accumulated 14 m of banded, gelatinous, sapropelic sediments in less than 104 yr. Stratigraphic evidence indicates that Mangrove Lake's sedimentary environment has undergone three major depositional changes (peat, freshwater gel, brackish-water gel) as a result of sea level changes. The deposits were examined geochemically in an effort to delineate sedimentological and diagenetic changes. Gas and pore water studies include measurements of sulfides, ammonia, methane, nitrogen gas, calcium, magnesium, chloride, alkalinity, and pH. Results indicate that sulfate reduction is complete, and some evidence is presented for bacterial denitrification and metal sulfide precipitation. The organic-rich sapropel is predominantly algal in origin, composed mostly of carbohydrates and insoluble macromolecular organic matter called humin with minor amounts of proteins, lipids, and humic acids. Carbohydrates and proteins undergo hydrolysis with depth in the marine sapropel but tend to be preserved in the freshwater sapropel. The humin, which has a predominantly aliphatic structure, increases linearly with depth and composes the greatest fraction of the organic matter. Humic acids are minor components and are more like polysaccharides than typical marine humic acids. Fatty acid distributions reveal that the lipids are of an algal and/or terrestrial plant source. Normal alkanes with a total concentration of 75 ppm exhibit two distribution maxima. One is centered about n-C22 with no odd/even predominance, suggestive of a degraded algal source. The other is centered at n-C31 with a distinct odd/even predominance indicative of a vascular plant origin. Stratigraphic changes in the sediment correlate to observed changes in the gas and pore water chemistry and the organic geochemistry. ?? 1982.

  3. Chemistry of organic carbon in soil with relationship to the global carbon cycle

    SciTech Connect

    Post, W.M. III )

    1988-09-01

    Soil organic carbon in active exchange with the atmosphere constitutes approximately two-thirds of the carbon in terrestrial ecosystems. The large size and long residence time of this pool make it an important component of the global carbon cycle. The amount of carbon stored in soils and the rate of exchange of soil carbon with the atmosphere depends on many factors related to the chemistry of soil organic matter. The amount of carbon stored in soil is determined by the balance of two biotic processes associated with productivity of terrestrial vegetation and decomposition of organic matter. Each of these processes have strong physical controls that can be related to the climate variables temperature and precipitation at a regional or global scale. Soil carbon density generally increases with increasing precipitation, and there is an increase in soil carbon with decreasing temperature for any particular level of precipitation. Various ecosystem disturbances alter the balances between production and decomposition and therefore change the amount of carbon in soil. The most severe perturbation is conversion of natural vegetation to cultivation. The amount of soil carbon and nitrogen change resulting from cultivation depends on the initial amounts of each. Average changes in nitrogen are about one half to one forth the corresponding average carbon changes. Analysis of carbon and nitrogen linkages in soil shed some light on soil carbon dynamics after conversion to agriculture. The amount of initial carbon lost is associated with the amount of carbon in excess of C/N ratio of about 12 to 14. Soils with a high C/N ratio lose a larger fraction of the initial carbon then those with low C/N ratios. Soils with high C/N ratios have a larger percentage of organic matter in slowly decomposing forms. Cultivation results in a lowered input of slowly decomposing material which causes a reduction in overall carbon levels.

  4. Validating the Use of Concept-Mapping as a Diagnostic Assessment Tool in Organic Chemistry: Implications for Teaching

    ERIC Educational Resources Information Center

    Lopez, Enrique; Kim, Jennifer; Nandagopal, Kiruthiga; Cardin, Nate; Shavelson, Richard J.; Penn, John H.

    2011-01-01

    Science, Technology, Engineering, and Mathematics (STEM) education has become a key focus in the U.S. government's public education agenda. Many STEM degrees require the successful completion of undergraduate introductory organic chemistry (O-Chem), which is notorious for its difficulty and high attrition rate. Concept Maps (CM) have been used as…

  5. Tetraglyme Trap for the Determination of Volatile Organic Compounds in Urban Air: Projects for Undergraduate Analytical Chemistry

    ERIC Educational Resources Information Center

    Hope, Wilbert W.; Johnson, Clyde; Johnson, Leon P.

    2004-01-01

    The differences in the levels of volatile organic compounds (VOCs), in the ambient air from the two urban locations, were studied by the undergraduate analytical chemistry students. Tetraglyme is very widely used due to its simplicity and its potential for use to investigate VOCs in ambient and indoor air employing a purge-and-trap concentrator…

  6. Self-Regulated Learning Study Strategies and Academic Performance in Undergraduate Organic Chemistry: An Investigation Examining Ethnically Diverse Students

    ERIC Educational Resources Information Center

    Lopez, Enrique J.; Nandagopal, Kiruthiga; Shavelson, Richard J.; Szu, Evan; Penn, John

    2013-01-01

    This study sought to identify ethnically diverse students' study strategies in organic chemistry and their relationships to course outcomes. Study diaries, concept maps, and problem sets were used to assess study outcomes. Findings show that students engage in four commonly used reviewing-type strategies, regardless of ethnic group affiliation.…

  7. The Cyclohexanol Cycle and Synthesis of Nylon 6,6: Green Chemistry in the Undergraduate Organic Laboratory

    ERIC Educational Resources Information Center

    Dintzner, Matthew R.; Kinzie, Charles R.; Pulkrabek, Kimberly; Arena, Anthony F.

    2012-01-01

    A one-term synthesis project that incorporates many of the principles of green chemistry is presented for the undergraduate organic laboratory. In this multistep scheme of reactions, students react, recycle, and ultimately convert cyclohexanol to nylon 6,6. The individual reactions in the project employ environmentally friendly methodologies, and…

  8. COMPUTATIONAL CHEMISTRY METHOD FOR PREDICTING VAPOR PRESSURES AND ACTIVITY COEFFICIENTS OF POLAR ORGANIC OXYGENATES IN PM2.5

    EPA Science Inventory

    Parameterizations of interactions of polar multifunctional organic oxygenates in PM2.5 must be included in aerosol chemistry models for evaluating control strategies for reducing ambient concentrations of PM2.5 compounds. Vapor pressures and activity coefficients of these compo...

  9. Bringing Research into a First Semester Organic Chemistry Laboratory with the Multistep Synthesis of Carbohydrate-Based HIV Inhibitor Mimics

    ERIC Educational Resources Information Center

    Pontrello, Jason K.

    2015-01-01

    Benefits of incorporating research experiences into laboratory courses have been well documented, yet examples of research projects designed for the first semester introductory organic chemistry lab course are extremely rare. To address this deficiency, a Carbohydrate-Based human immunodeficiency virus (HIV) Inhibitor project consisting of a…

  10. Extraction and [superscript 1]H NMR Analysis of Fats from Convenience Foods: A Laboratory Experiment for Organic Chemistry

    ERIC Educational Resources Information Center

    Hartel, Aaron M.; Moore, Amy C.

    2014-01-01

    The extraction and analysis of fats from convenience foods (crackers, cookies, chips, candies) has been developed as an experiment for a second-year undergraduate organic chemistry laboratory course. Students gravimetrically determine the fat content per serving and then perform a [superscript 1]H NMR analysis of the recovered fat to determine the…

  11. Two Methods of Determining Total Phenolic Content of Foods and Juices in a General, Organic, and Biological (GOB) Chemistry Lab

    ERIC Educational Resources Information Center

    Shaver, Lee Alan; Leung, Sam H.; Puderbaugh, Amy; Angel, Stephen A.

    2011-01-01

    The determination of total phenolics in foods and fruit juices was used successfully as a laboratory experiment in our undergraduate general, organic, and biological (GOB) chemistry course. Two different colorimetric methods were used over three years and comparative student results indicate that a ferrous ammonium sulfate (FAS) indicator…

  12. ConfChem Conference on Flipped Classroom: Improving Student Engagement in Organic Chemistry Using the Inverted Classroom Model

    ERIC Educational Resources Information Center

    Rossi, Robert D.

    2015-01-01

    Improving student engagement in STEM (science, technology, engineering, and mathematics) courses generally, and organic chemistry specifically, has long been a goal for educators. Recently educators at all academic levels have been exploring the "inverted classroom" or "flipped classroom" pedagogical model for improving student…

  13. Development and Implementation of a First-Semester Hybrid Organic Chemistry Course: Yielding Advantages for Educators and Students

    ERIC Educational Resources Information Center

    Ealy, Julie B.

    2013-01-01

    A first-semester organic chemistry course was developed as a hybrid course. The students met face-to-face for one class each week (50 minutes) and the lectures were accessible online via Adobe Connect. Quizzes were scheduled for almost every lecture with access online through ANGEL. In addition, the students had three in-class tests and one final…

  14. Nickel-Catalyzed Suzuki-Miyaura Cross-Coupling in a Green Alcohol Solvent for an Undergraduate Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Hie, Liana; Chang, Jonah J.; Garg, Neil K.

    2015-01-01

    A modern undergraduate organic chemistry laboratory experiment involving the Suzuki-Miyaura coupling is reported. Although Suzuki-Miyaura couplings typically employ palladium catalysts in environmentally harmful solvents, this experiment features the use of inexpensive nickel catalysis, in addition to a "green" alcohol solvent. The…

  15. The Effects of Online Homework on First Year Pre-Service Science Teachers' Learning Achievements of Introductory Organic Chemistry

    ERIC Educational Resources Information Center

    Ratniyom, Jadsada; Boonphadung, Suttipong; Unnanantn, Thassanant

    2016-01-01

    This study examined the effects of the introductory organic chemistry online homework on first year pre-service science teachers' learning achievements. The online homework was created using a web-based Google form in order to enhance the pre-service science teachers' learning achievements. The steps for constructing online homework were…

  16. Development and Assessment of a Diagnostic Tool to Identify Organic Chemistry Students' Alternative Conceptions Related to Acid Strength

    ERIC Educational Resources Information Center

    McClary, LaKeisha M.; Bretz, Stacey Lowery

    2012-01-01

    The central goal of this study was to create a new diagnostic tool to identify organic chemistry students' alternative conceptions related to acid strength. Twenty years of research on secondary and college students' conceptions about acids and bases has shown that these important concepts are difficult for students to apply to qualitative problem…

  17. Lewis base mediated efficient synthesis and solvation-like host-guest chemistry of covalent organic framework-1.

    PubMed

    Kalidindi, Suresh Babu; Wiktor, Christian; Ramakrishnan, Ayyappan; Weßing, Jana; Schneemann, Andreas; Van Tendeloo, Gustaaf; Fischer, Roland A

    2013-01-18

    N-Lewis base mediated room temperature synthesis of covalent organic frameworks (COFs) starting from a solution of building blocks instead of partially soluble building blocks was developed. This protocol shifts COF synthetic chemistry from sealed tubes to open beakers. Non-conventional inclusion compounds of COF-1 were obtained by vapor phase infiltration of ferrocene and azobenzene, and solvation like effects were established.

  18. Quantitative Measurement of Magnetic Hyperfine Parameters and the Physical Organic Chemistry of Supramolecular Systems

    NASA Astrophysics Data System (ADS)

    Bender, Christopher J.

    The physical principles that underlie organic reactions were established by a systematic study of chemical reaction dynamics that employed correlated measurements of reaction rates and a physical parameter that could be related of the electronic properties of the molecules in question (Hammett, 1970). Today, molecular science emphasizes the concept of molecular device, which connotes a supramolecular structure (the term "supramolecule" loosely means a molecule that has multiple functionalities associated with it; for example, an enzyme might be regarded as a supramolecule in the sense that it features a supported metal catalyst and a receptor site that recognizes a specific substrate upon which the catalyst acts) that acts in some specific fashion. A molecular device may be biological (e.g., enzymes, contractile proteins; cf. Tanford & Reynolds, 2001), or it may be produced by synthetic means (e.g., molecular wires, switches, machines, etc.; cf. Sauvage, 2001; Balzani et al., 2003). Current synthetic chemistry provides the technical means that enable one to create and modify molecular devices so that structure may elicit some specific function, and so physical organic chemists are interested in reactions that involve engineered and structurally complex systems such as supported catalysts, protein active sites, or nanostructures (cf. amilton, 1996; Tidwell et al., 1997).

  19. Organic Chemistry Course Development in a Forensic Science Program: Use of FT-NMR

    NASA Astrophysics Data System (ADS)

    Callahan, Ronald; Kobilinsky, Lawrence; Rothchild, Robert

    1999-10-01

    The acquisition of a modern, multinuclear, medium-field (7 tesla) FT-NMR, with partial support from NSF-ILI, has made possible the introduction of a major special project for second-semester organic chemistry laboratory, within a forensic science program. The eight-week special project focuses on microscale syntheses of Diels-Alder adducts of phencyclone. Students synthesize a wide range of different N-substituted maleimides for use as dienophiles. The corresponding phencyclone adducts permit studies of: a) unusual hindered rotations of unsubsituted bridgehead phenyls, b) striking examples of magnetic anisotropic effects, and c) modern one- and two-dimensional NMR methods for structural characterization. Use of fluorine-containing dienophiles provides a basis for examining NMR spectra of three different NMR-active nuclei: proton, carbon-13, and fluorine-19. Variable-temperature NMR is also applicable to these compounds. Molecular modeling software has been introduced in the organic laboratory course for students to examine the geometry of these adducts, precursors, and simplified model compounds, and to evaluate geometric parameters in structures that are optimized by semi-empirical and ab initio calculations. References are included with the article and can be accessed via its PDF file.

  20. Beyond static structures: Putting forth REMD as a tool to solve problems in computational organic chemistry.

    PubMed

    Petraglia, Riccardo; Nicolaï, Adrien; Wodrich, Matthew D; Ceriotti, Michele; Corminboeuf, Clemence

    2016-01-05

    Computational studies of organic systems are frequently limited to static pictures that closely align with textbook style presentations of reaction mechanisms and isomerization processes. Of course, in reality chemical systems are dynamic entities where a multitude of molecular conformations exists on incredibly complex potential energy surfaces (PES). Here, we borrow a computational technique originally conceived to be used in the context of biological simulations, together with empirical force fields, and apply it to organic chemical problems. Replica-exchange molecular dynamics (REMD) permits thorough exploration of the PES. We combined REMD with density functional tight binding (DFTB), thereby establishing the level of accuracy necessary to analyze small molecular systems. Through the study of four prototypical problems: isomer identification, reaction mechanisms, temperature-dependent rotational processes, and catalysis, we reveal new insights and chemistry that likely would be missed using static electronic structure computations. The REMD-DFTB methodology at the heart of this study is powered by i-PI, which efficiently handles the interface between the DFTB and REMD codes.

  1. On-demand droplet loading for automated organic chemistry on digital microfluidics.

    PubMed

    Shah, Gaurav J; Ding, Huijiang; Sadeghi, Saman; Chen, Supin; Kim, Chang-Jin C J; van Dam, R Michael

    2013-07-21

    Organic chemistry applications on digital microfluidic devices often involve reagents that are volatile or sensitive and must be introduced to the chip immediately before use. We present a new technique for automated, on-demand loading of ~1 μL droplets from large (~1 mL), sealed, off-chip reservoirs to a digital microfluidic chip in order to address this challenge. Unlike aqueous liquids which generally are non-wetting to the hydrophobic surface and must be actively drawn into the electrowetting-on-dielectric (EWOD) chip by electrode activation, organic liquids tend to be wetting and can spontaneously flood the chip, and hence require a retracting force for controlled liquid delivery. Using a combination of compressed inert gas and gravity to exert driving and retracting forces on the liquid, the simple loading technique enables precise loading of droplets of both wetting and non-wetting liquids in a reliable manner. A key feature from a practical point of view is that all of the wetted parts are inexpensive and potentially disposable, thus avoiding cross-contamination in chemical and biochemical applications. We provide a theoretical treatment of the underlying physics, discuss the effect of geometry and liquid properties on its performance, and show repeatable reagent loading using the technique. Its versatility is demonstrated with the loading of several aqueous and non-aqueous liquids on an EWOD digital microfluidic device.

  2. Quantum Chemistry in Nanoscale Environments: Insights on Surface-Enhanced Raman Scattering and Organic Photovoltaics

    NASA Astrophysics Data System (ADS)

    Olivares-Amaya, Roberto

    The understanding of molecular effects in nanoscale environments is becoming increasingly relevant for various emerging fields. These include spectroscopy for molecular identification as well as in finding molecules for energy harvesting. Theoretical quantum chemistry has been increasingly useful to address these phenomena to yield an understanding of these effects. In the first part of this dissertation, we study the chemical effect of surface-enhanced Raman scattering (SERS). We use quantum chemistry simulations to study the metal-molecule interactions present in these systems. We find that the excitations that provide a chemical enhancement contain a mixed contribution from the metal and the molecule. Moreover, using atomistic studies we propose an additional source of enhancement, where a transition metal dopant surface could provide an additional enhancement. We also develop methods to study the electrostatic effects of molecules in metallic environments. We study the importance of image-charge effects, as well as field-bias to molecules interacting with perfect conductors. The atomistic modeling and the electrostatic approximation enable us to study the effects of the metal interacting with the molecule in a complementary fashion, which provides a better understanding of the complex effects present in SERS. In the second part of this dissertation, we present the Harvard Clean Energy Project, a high-throughput approach for a large-scale computational screening and design of organic photovoltaic materials. We create molecular libraries to search for candidates structures and use quantum chemistry, machine learning and cheminformatics methods to characterize these systems and find structure-property relations. The scale of this study requires an equally large computational resource. We rely on distributed volunteer computing to obtain these properties. In the third part of this dissertation we present our work related to the acceleration of electronic structure

  3. The Impacts of Marine Organic Emissions on Atmospheric Chemistry and Climate (Invited)

    NASA Astrophysics Data System (ADS)

    Meskhidze, N.; Gantt, B.

    2013-12-01

    Using laboratory studies and global/regional climate model results, this talk will contribute to two main research questions: 1) what can be learned about the carbon emission inducing stress factors for marine algae, and 2) what is a potential impact of marine biogenic volatile organic compound (VOC) emissions on global atmospheric chemistry and climate. Marine photosynthetic organisms emit VOCs which can form secondary organic aerosols (SOA). Currently large uncertainty exists in the magnitude of the marine biogenic sources, their spatiotemporal distribution, controlling factors, and contributions to natural background of organic aerosols. Here laboratory results for the production of isoprene and four monoterpene (α-pinene, β-pinene, camphene and d-limonene) compounds as a function of variable light and temperature regimes for 6 different phytoplankton species will be discussed. The experiment was designed to simulate the regions where phytoplankton is subjected to changeable light/temperature conditions. The samples were grown and maintained at a climate controlled room. VOCs accumulated in the water and headspace above the water were measured by passing the sample through a gas chromatography/mass system equipped with a sample pre-concentrator allowing detection of low ppt levels of hydrocarbons. The VOC production rates were distinctly different for light/temperature stressed (the first 12 hour cycle at light/temperature levels higher than what the cultures were acclimated to in a climate controlled room) and photo/temperature-acclimated (the second 12 hour light/temperature cycle) states. In general, all phytoplankton species showed a rapid increase in isoprene and monoterpene production at higher light levels (between 150 to 420 μE m-2 s-1) until a constant production rate was reached. Isoprene and α-pinene, production rates also increased with temperature until a certain level, after which the rates declined as temperature increased further. Two

  4. Designing Undergraduate-Level Organic Chemistry Instructional Problems: Seven Ideas from a Problem-Solving Study of Practicing Synthetic Organic Chemists

    ERIC Educational Resources Information Center

    Raker, Jeffrey R.; Towns, Marcy H.

    2012-01-01

    The development of curricular problems based on the practice of synthetic organic chemistry has not been explored in the literature. Such problems have broadly been hypothesized to promote student persistence and interest in STEM fields. This study reports seven ideas about how practice-based problems can be developed for sophomore-level organic…

  5. Improving Students' Understanding of Molecular Structure through Broad-Based Use of Computer Models in the Undergraduate Organic Chemistry Lecture

    ERIC Educational Resources Information Center

    Springer, Michael T.

    2014-01-01

    Several articles suggest how to incorporate computer models into the organic chemistry laboratory, but relatively few papers discuss how to incorporate these models broadly into the organic chemistry lecture. Previous research has suggested that "manipulating" physical or computer models enhances student understanding; this study…

  6. The Role of Organic Nitrates in the Chemistry of the Continents: An Assessment Using WRF-CHEM

    NASA Astrophysics Data System (ADS)

    Zare, A.; Cohen, R. C.; Romer, P.

    2015-12-01

    Nitrogen oxides (NOx) play a fundamental role in the chemistry of atmospheric oxidation and affect air quality and climate. Recent experiments have shown that formation of organic nitrates is a more important immediate sink of NOx than nitric acid in the rural continental locations. In particular, in regions with high emissions of biogenic volatile organic compounds (BVOCs), isoprene and monoterpene derived organic nitrates can be expected to control the fate of nitrogen oxides, and consequently the ozone production efficiency. Thus understanding of the complex production and loss processes of organic nitrates are required for determining the lifetime of NOx in the present day and in preindustrial times. Using the chemical transport model WRF-Chem, we investigate impacts of organic nitrate chemistry on the NOx and ozone budgets of the southeastern United States. We evaluate changes to the NOx budget in response to decreases in anthropogenic NOx emissions. The model has been updated with recent advances in representation of BVOC oxidation chemistry and deposition rates, including a detailed representation of organic nitrates. We compared simulations to measurements from the Southern Oxidant and Aerosol Study (SOAS) campaign in central Alabama in summer 2013 and examine the sensitivity to emission rates.

  7. Design of Organic Transformations at Ambient Conditions: Our Sincere Efforts to the Cause of Green Chemistry Practice.

    PubMed

    Brahmachari, Goutam

    2016-02-01

    This account summarizes our recent efforts in designing a good number of important organic transformations leading to the synthesis of biologically relevant compounds at room temperature and pressure. Currently, the concept of green chemistry is globally acclaimed and has already advanced quite significantly to emerge as a distinct branch of chemical sciences. Among the principles of green chemistry, one principle is dedicated to the "design of energy efficiency" - that is, to develop synthetic strategies that require less or the minimum amount of energy to carry out a specific reaction with optimum productivity - and the most effective way to save energy is to develop strategies/protocols that are capable enough to carry out the transformations at ambient temperature! As part of on-going developments in green synthetic strategies, the design of reactions under ambient conditions coupled with other green aspects is, thus, an area of current interest. The concept of developing reaction strategies at room temperature and pressure is now an emerging field of research in organic chemistry and is progressing steadily. This account is aimed to offer an overview of our recent research works directly related to this particular field of interest, and highlights the green chemistry practice leading to carbon-carbon and carbon-heteroatom bond-forming reactions of topical significance. Green synthetic routes to a variety of biologically relevant organic molecules (heterocyclic, heteroaromatic, alicyclic, acyclic, etc.) at room temperature and pressure are discussed.

  8. Zirconocene and Si-tethered diynes: a happy match directed toward organometallic chemistry and organic synthesis.

    PubMed

    Zhang, Wen-Xiong; Zhang, Shaoguang; Xi, Zhenfeng

    2011-07-19

    Characterizing reactive organometallic intermediates is critical for understanding the mechanistic aspects of metal-mediated organic reactions. Moreover, the isolation of reactive organometallic intermediates can often result in the ability to design new synthetic methods. In this Account, we outline synthetic methods that we developed for a variety of diverse Zr/Si organo-bimetallic compounds and Si/N heteroatom-organic compounds through the detailed study of zirconacyclobutene-silacyclobutene fused compounds. Two basic components are involved in this chemistry. The first is the Si-tethered diyne, which owes its rich reactive palette to the combination of the Si-C bond and the C≡C triple bond. The second is the low-valent zirconocene species Cp(2)Zr(II), which has proven very useful in organic synthesis. The reaction of these two components affords the zirconacyclobutene-silacyclobutene fused compound, which is the key reactive Zr/Si organo-bimetallic intermediate discussed here. We discuss the three types of reactions that have been developed for the zirconacyclobutene-silacyclobutene fused intermediate. The reaction with nitriles (the C≡N triple bond) is introduced in the first section. In this one-pot reaction, up to four different components can be combined: the Si-tethered diyne can be reacted with three identical nitriles, with differing nitriles, or with a nitrile and other unsaturated organic substrates such as formamides, isocyanides, acid chlorides, aldehydes, carbodiimides, and azides. Several unexpected multiring, fused Zr/Si organo-bimetallic intermediates were isolated and characterized. A wide variety of N-heterocycles, such as 5-azaindole, pyrrole, and pyrroloazepine derivatives, were obtained. We then discuss the reaction with alkynes (the C≡C triple bond). A consecutive skeletal rearrangement, differing from that observed in the reactions with nitriles, takes place in this reaction. Finally, we discuss the reaction with the C═X substrates

  9. Nucleic acid chemistry in the organic phase: from functionalized oligonucleotides to DNA side chain polymers.

    PubMed

    Liu, Kai; Zheng, Lifei; Liu, Qing; de Vries, Jan Willem; Gerasimov, Jennifer Y; Herrmann, Andreas

    2014-10-08

    DNA-incorporating hydrophobic moieties can be synthesized by either solid-phase or solution-phase coupling. On a solid support the DNA is protected, and hydrophobic units are usually attached employing phosphoramidite chemistry involving a DNA synthesizer. On the other hand, solution coupling in aqueous medium results in low yields due to the solvent incompatibility of DNA and hydrophobic compounds. Hence, the development of a general coupling method for producing amphiphilic DNA conjugates with high yield in solution remains a major challenge. Here, we report an organic-phase coupling strategy for nucleic acid modification and polymerization by introducing a hydrophobic DNA-surfactant complex as a reactive scaffold. A remarkable range of amphiphile-DNA structures (DNA-pyrene, DNA-triphenylphosphine, DNA-hydrocarbon, and DNA block copolymers) and a series of new brush-type DNA side-chain homopolymers with high DNA grafting density are produced efficiently. We believe that this method is an important breakthrough in developing a generalized approach to synthesizing functional DNA molecules for self-assembly and related technological applications.

  10. Ionic Liquids Beyond Simple Solvents: Glimpses at the State of the Art in Organic Chemistry

    PubMed Central

    Kuchenbuch, Andrea

    2015-01-01

    Abstract Within the last 25 years ionic liquids have written a tremendous success story, which is documented in a nearly uncountable amount of original research papers, reviews, and numerous applications in research and industry. These days, ionic liquids can be considered as a mature class of compounds for many different applications. Frequently, they are used as neoteric solvents for chemical tansformations, and the number of reviews on this field of research is huge. In this focused review, though, we are trying to evaluate the state of the art of ionic liquid chemistry beyond using them simply as solvents for chemical transformations. It is not meant to be a comprehensive overview on the topic; the choice of emphasis and examples rather refects the authors’ personal view on the field. We are especially highlighting fields in which we believe the most fundamental developments within the next five years will take place: biomass processing, (chiral) ionic liquids from natural sources, biotransformations, and organic synthesis. PMID:27308192

  11. Organic Chemistry Online: Building Collaborative Learning Communities through Electronic Communication Tools

    NASA Astrophysics Data System (ADS)

    Glaser, Rainer E.; Poole, Melissa J.

    1999-05-01

    How do we make the undergraduate "large lecture" class seem like a small learning community? How can we utilize the new computer-mediated communication tools on the Internet to enhance communication and engage students in active learning? In this article, we report on the use of group research projects in an undergraduate course in organic chemistry to build small learning communities. Students engaged in group research projects via online resources and developed reports that were published online. They also worked together in groups to review the online reports of their peers. This work was facilitated by use of electronic media, including the course Web site, email, and an electronic discussion list. The resulting projects far exceeded our expectations. Students reported that the process of collaborative group work was beneficial for studying as well as for project work. Future plans include refinement of the research project assignment, development of an automated Web tool for reporting and calculating peer review scores, and refinement of the course evaluation tools.

  12. Using biocatalysis to integrate organic chemistry into a molecular biology laboratory course.

    PubMed

    Beers, Mande; Archer, Crystal; Feske, Brent D; Mateer, Scott C

    2012-01-01

    Current cutting-edge biomedical investigation requires that the researcher have an operational understanding of several diverse disciplines. Biocatalysis is a field of science that operates at the crossroads of organic chemistry, biochemistry, microbiology, and molecular biology, and provides an excellent model for interdisciplinary research. We have developed an inquiry-based module that uses the mutagenesis of the yeast reductase, YDL124w, to study the bioorganic synthesis of the taxol side-chain, a pharmacologically important molecule. Using related structures, students identify regions they think will affect enzyme stereoselective, design and generate site-specific mutants, and then characterize the effect of these changes on enzyme activity. This laboratory activity gives our students experience, working in a scientific discipline outside of biology and exposes them to techniques and equipment they do not normally work with in a molecular biology course. These inter-disciplinary experiences not only show the relevance of other sciences to biology, but also give our students the ability to communicate more effectively with scientists outside their discipline.

  13. Meaningful Understanding and Systems Thinking in Organic Chemistry: Validating Measurement and Exploring Relationships

    NASA Astrophysics Data System (ADS)

    Vachliotis, Theodoros; Salta, Katerina; Tzougraki, Chryssa

    2014-04-01

    The purpose of this study was dual: First, to develop and validate assessment schemes for assessing 11th grade students' meaningful understanding of organic chemistry concepts, as well as their systems thinking skills in the domain. Second, to explore the relationship between the two constructs of interest based on students' performance on the applied assessment framework. For this purpose, (a) various types of objective assessment questions were developed and evaluated for assessing meaningful understanding, (b) a specific type of systemic assessment questions (SAQs) was developed and evaluated for assessing systems thinking skills, and (c) the association between students' responses on the applied assessment schemes was explored. The results indicated that properly designed objective questions can effectively capture aspects of students' meaningful understanding. It was also found that the SAQs can elicit systems thinking skills in the context of a formalistic systems thinking theoretical approach. Moreover, a significant relationship was observed between students' responses on the two assessment strategies. This research provides evidence that students' systems thinking level within a science domain is significantly related to their meaningful understanding of relative science concepts.

  14. Evaluation of NO+ reagent ion chemistry for online measurements of atmospheric volatile organic compounds

    NASA Astrophysics Data System (ADS)

    Koss, Abigail R.; Warneke, Carsten; Yuan, Bin; Coggon, Matthew M.; Veres, Patrick R.; de Gouw, Joost A.

    2016-07-01

    NO+ chemical ionization mass spectrometry (NO+ CIMS) can achieve fast (1 Hz and faster) online measurement of trace atmospheric volatile organic compounds (VOCs) that cannot be ionized with H3O+ ions (e.g., in a PTR-MS or H3O+ CIMS instrument). Here we describe the adaptation of a high-resolution time-of-flight H3O+ CIMS instrument to use NO+ primary ion chemistry. We evaluate the NO+ technique with respect to compound specificity, sensitivity, and VOC species measured compared to H3O+. The evaluation is established by a series of experiments including laboratory investigation using a gas-chromatography (GC) interface, in situ measurement of urban air using a GC interface, and direct in situ measurement of urban air. The main findings are that (1) NO+ is useful for isomerically resolved measurements of carbonyl species; (2) NO+ can achieve sensitive detection of small (C4-C8) branched alkanes but is not unambiguous for most; and (3) compound-specific measurement of some alkanes, especially isopentane, methylpentane, and high-mass (C12-C15) n-alkanes, is possible with NO+. We also demonstrate fast in situ chemically specific measurements of C12 to C15 alkanes in ambient air.

  15. Adsorption and desorption of dissolved organic matter by carbon nanotubes: Effects of solution chemistry.

    PubMed

    Engel, Maya; Chefetz, Benny

    2016-06-01

    Increasing use of carbon nanotubes (CNTs) has led to their introduction into the environment where they can interact with dissolved organic matter (DOM). This study focuses on solution chemistry effects on DOM adsorption/desorption processes by single-walled CNTs (SWCNTs). Our data show that DOM adsorption is controlled by the attachment of DOM molecules to the SWCNTs, and that the initial adsorption rate is dependent on solution parameters. Adsorbed amount of DOM at high ionic strength was limited, possibly due to alterations in SWCNT bundling. Desorption of DOM performed at low pH resulted in additional DOM adsorption, whereas at high pH, adsorbed DOM amount decreased. The extent of desorption conducted at increased ionic strength was dependent on pre-adsorbed DOM concentration: low DOM loading stimulated additional adsorption of DOM, whereas high DOM loading facilitated release of adsorbed DOM. Elevated ionic strength and increased adsorbed amount of DOM reduced the oxidation temperature of the SWCNTs, suggesting that changes in the assembly of the SWCNTs had occurred. Moreover, DOM-coated SWCNTs at increased ionic strength provided fewer sites for atrazine adsorption. This study enhances our understanding of DOM-SWCNT interactions in aqueous systems influenced by rapid changes in salinity, and facilitates potential use of SWCNTs in water-purification technologies.

  16. Responsive hydrogels produced via organic sol-gel chemistry for cell culture applications.

    PubMed

    Patil, Smruti; Chaudhury, Pulkit; Clarizia, Lisa; McDonald, Melisenda; Reynaud, Emmanuelle; Gaines, Peter; Schmidt, Daniel F

    2012-08-01

    In this study, we report the synthesis of novel environmentally responsive polyurea hydrogel networks prepared via organic sol-gel chemistry and demonstrate that the networks can stabilize pH while releasing glucose both in simple aqueous media and in mammalian cell culture settings. Hydrogel formulations have been developed based on the combination of an aliphatic triisocyanate with pH-insensitive amine functional polyether and pH-sensitive poly(ethyleneimine) segments in a minimally toxic solvent suitable for the sol-gel reaction. The polyether component of the polyurea network is sufficiently hydrophilic to give rise to some level of swelling independent of environmental pH, while the poly(ethyleneimine) component contains tertiary amine groups providing pH sensitivity to the network in the form of enhanced swelling and release under acidic conditions. The reaction of these materials to form a network is rapid and requires no catalyst. The resultant material exhibits the desired pH-responsive swelling behavior and demonstrates its ability to simultaneously neutralize lactic acid and release glucose in both cell-free culture media and mammalian cell culture, with no detectable evidence of cytotoxicity or changes in cell behavior, in the case of either SA-13 human hybridomas or mouse embryonic stem cells. Furthermore, pH is observed to have a clear effect on the rate at which glucose is released from the hydrogel network. Such characteristics promise to maintain a favorable cell culture environment in the absence of human intervention.

  17. The meteoritic record of presolar and early solar system organic chemistry. [Abstract only

    NASA Technical Reports Server (NTRS)

    Cronin, John R.; Pizzarello, Sandra

    1994-01-01

    Carbon, hydrogen, and nitrogen isotopic analyses of various classes of organic compounds done in collaboration with Epstein and Krishnamurthy (Caltech) have shown these compounds to be enriched to varying degrees in the heavier isotopes. These results, in particular the large deuterium enrichments, have been interpreted as indicating an interstellar origin for the meteorite compounds or their precursors. Such isotopic fractionations, of hydrogen especially, are characteristic of low temperature ion-molecule reactions in cold interstellar clouds. There is also evidence from the large corresponding suites of alpha-amino and alpha-hydroxy acids found in meteorites suggesting that aqueous phase chemistry on the meteorite parent body played an important role in the formation of these compounds. These data support the hypothesis that interstellar compounds survived in the solar nebula at a radial distance corresponding to the asteroid belt, were incorporated into the parent body in icy, volatile-rich, planetesinals, and underwent further reactions during a period of aqueous activity within the early parent body to give the present suite of meteorite compounds. This formation hypothesis will be discussed and the results of recent isotopic and molecular analyses bearing on it will be presented.

  18. Creating a Discovery Platform for Confined-Space Chemistry and Materials: Metal-Organic Frameworks.

    SciTech Connect

    Allendorf, Mark D.; Greathouse, Jeffery A.; Simmons, Blake

    2008-09-01

    Metal organic frameworks (MOF) are a recently discovered class of nanoporous, defect-free crystalline materials that enable rational design and exploration of porous materials at the molecular level. MOFs have tunable monolithic pore sizes and cavity environments due to their crystalline nature, yielding properties exceeding those of most other porous materials. These include: the lowest known density (91% free space); highest surface area; tunable photoluminescence; selective molecular adsorption; and methane sorption rivaling gas cylinders. These properties are achieved by coupling inorganic metal complexes such as ZnO4 with tunable organic ligands that serve as struts, allowing facile manipulation of pore size and surface area through reactant selection. MOFs thus provide a discovery platform for generating both new understanding of chemistry in confined spaces and novel sensors and devices based on their unique properties. At the outset of this project in FY06, virtually nothing was known about how to couple MOFs to substrates and the science of MOF properties and how to tune them was in its infancy. An integrated approach was needed to establish the required knowledge base for nanoscale design and develop methodologies integrate MOFs with other materials. This report summarizes the key accomplishments of this project, which include creation of a new class of radiation detection materials based on MOFs, luminescent MOFs for chemical detection, use of MOFs as templates to create nanoparticles of hydrogen storage materials, MOF coatings for stress-based chemical detection using microcantilevers, and "flexible" force fields that account for structural changes in MOFs that occur upon molecular adsorption/desorption. Eight journal articles, twenty presentations at scientific conferences, and two patent applications resulted from the work. The project created a basis for continuing development of MOFs for many Sandia applications and succeeded in securing $2.75 M in

  19. Semiempirical and ab initio Calculations of Charged Species Used in the Physical Organic Chemistry Course.

    ERIC Educational Resources Information Center

    Gilliom, Richard D.

    1989-01-01

    Concentrates on the semiempirical methods MINDO/3, MNDO, and AMI available in the program AMPAC from the Quantum Chemistry Program Exchange at Indiana University. Uses charged ions in the teaching of computational chemistry. Finds that semiempirical methods are accurate enough for the general use of the bench chemist. (MVL)

  20. TextRev: A Window into How General and Organic Chemistry Students Use Textbook Resources.

    ERIC Educational Resources Information Center

    Smith, Bradley D.; Jacobs, Dennis C.

    2003-01-01

    Points out the important use of textbooks and their ancillary resources in lower-division chemistry courses and the scientific misconceptions found in them. Introduces the TextRev Project which is a new resource for data collection and analysis. Investigates how first and second year chemistry students use and value their textbooks and their study…

  1. Illustrating Concepts in Physical Organic Chemistry with 3D Printed Orbitals

    ERIC Educational Resources Information Center

    Robertson, Michael J.; Jorgensen, William L.

    2015-01-01

    Orbital theory provides a powerful tool for rationalizing and understanding many phenomena in chemistry. In most introductory chemistry courses, students are introduced to atomic and molecular orbitals in the form of two-dimensional drawings. In this work, we describe a general method for producing 3D printing files of orbital models that can be…

  2. The Construction of Metal-Organic Framework with Active Backbones by the Utilization of Reticular Chemistry

    NASA Astrophysics Data System (ADS)

    Choi, Eunwoo

    With the principles of reticular chemistry, metal-organic frameworks with ultra-high porosity, chiral-recognition unit as a chiral stationary phase, metalloporhyrins for enhanced hydrogen adsorption and an intrinsic conductivity to form porous conductors, have been prepared. This dissertation presents how the principles of reticular chemistry were utilized to achieve in the preparations of metal-organic frameworks with a large surface area and active backbones. Through the simple isoreticular (having the same framework topology) expansion from MOF-177 composed with 1,3,5-tris(4'-carboxyphenyl-)benzene (BTB3-) as the strut; MOF-200 was prepared with 4,4',4"-(benzene-1,3,5-triyl-tris(benzene-4,1-diy1))tribenzoic acid an extension from BTB3- by a phenylene unit to yield one of the most porous MOFs with a Langmuir surface area of 10,400 m2. and the lowest density of 0.22 cm3.g-1. A successful thermal polymerization reaction at 325 °C inside of the pores of highly porous MOF, MOF-177, was performed and verified the integrity of the MOF structure even after the thermal reaction. 1,4-Diphenylbutadiyne that is known to polymerize upon heating to form a conjugated backbone was impregnated via solution-diffusion into MOF-177 and then subsequently polymerized by heat to form polymer impregnated MOF-177. Characterization was carried out using powder X-ray diffraction and volumetric sorption analyzer. MOF-1020 with a linear quaterphenyl dicarboxylate-based strut was designed to contain a chiral bisbinaphthyl crown-ether moiety for alkyl ammonium resolution was precisely placed into a Zn4O(CO2)6-based cubic MOF structure. Unfortunately, the chiral resolution was not achieved due to the sensitivity and the pore environment of MOF-1020. However, an interesting phenomenon was observed, where the loss of crystallinity occurs upon solvent removal while the crystallites remain shiny and crystalline, but it readily is restored upon re-solvation of the crystallites. This rare

  3. Chemistry of carbon nanomaterials: Uses of lithium nanotube salts in organic syntheses and functionalization of graphite

    NASA Astrophysics Data System (ADS)

    Chattopadhyay, Jayanta

    transfer (SET) mechanism to functionalize carbon nanotubes with different alkyl/aryl groups. Using the reductive alkylation approach, we can also functionalize graphites by alkyl/carboxylic acid groups, making graphite soluble in organic solvents and water. Tailoring of graphite layers is also accomplished by using different metals in liquid ammonia. Finally, SWNT-epoxides/graphite epoxides are synthesized using m-CPBA. Quantification of the epoxide substituents on the nanotube/graphite surface is evaluated through the catalytic de-epoxidation reaction using MeReO 3/PPh3 as heterogeneous catalyst. In summary, the proposed covalent functionalization methods yield derivatized nanomaterials that can provide a solid platform for a number of exciting applications, ranging from material science to biomedical devices. Furthermore, the results presented in this thesis provide insight into the molecular chemistry at nano-resolution.

  4. Exploring Atmospheric Aqueous Chemistry (and Secondary Organic Aerosol Formation) through OH Radical Oxidation Experiments, Droplet Evaporation and Chemical Modeling

    NASA Astrophysics Data System (ADS)

    Turpin, B. J.; Kirkland, J. R.; Lim, Y. B.; Ortiz-Montalvo, D. L.; Sullivan, A.; Häkkinen, S.; Schwier, A. N.; Tan, Y.; McNeill, V. F.; Collett, J. L.; Skog, K.; Keutsch, F. N.; Sareen, N.; Carlton, A. G.; Decesari, S.; Facchini, C.

    2013-12-01

    Gas phase photochemistry fragments and oxidizes organic emissions, making water-soluble organics ubiquitous in the atmosphere. My group and others have found that several water-soluble compounds react further in the aqueous phase forming low volatility products under atmospherically-relevant conditions (i.e., in clouds, fogs and wet aerosols). Thus, secondary organic aerosol can form as a result of gas followed by aqueous chemistry (aqSOA). We have used aqueous OH radical oxidation experiments coupled with product analysis and chemical modeling to validate and refine the aqueous chemistry of glyoxal, methylglyoxal, glycolaldehyde, and acetic acid. The resulting chemical model has provided insights into the differences between oxidation chemistry in clouds and in wet aerosols. Further, we conducted droplet evaporation experiments to characterize the volatility of the products. Most recently, we have conducted aqueous OH radical oxidation experiments with ambient mixtures of water-soluble gases to identify additional atmospherically-important precursors and products. Specifically, we scrubbed water-soluble gases from the ambient air in the Po Valley, Italy using four mist chambers in parallel, operating at 25-30 L min-1. Aqueous OH radical oxidation experiments and control experiments were conducted with these mixtures (total organic carbon ≈ 100 μM-C). OH radicals (3.5E-2 μM [OH] s-1) were generated by photolyzing H2O2. Precursors and products were characterized using electrospray ionization mass spectrometry (ESI-MS), ion chromatography (IC), IC-ESI-MS, and ultra high resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). Chemical modeling suggests that organic acids (e.g., oxalate, pyruvate, glycolate) are major products of OH radical oxidation at cloud-relevant concentrations, whereas organic radical - radical reactions result in the formation of oligomers in wet aerosols. Products of cloud chemistry and droplet evaporation have

  5. Microwave-assisted chemistry: synthetic applications for rapid assembly of nanomaterials and organics.

    PubMed

    Gawande, Manoj B; Shelke, Sharad N; Zboril, Radek; Varma, Rajender S

    2014-04-15

    The magic of microwave (MW) heating technique, termed the Bunsen burner of the 21st century, has emerged as a valuable alternative in the synthesis of organic compounds, polymers, inorganic materials, and nanomaterials. Important innovations in MW-assisted chemistry now enable chemists to prepare catalytic materials or nanomaterials and desired organic molecules, selectively, in almost quantitative yields and with greater precision than using conventional heating. By controlling the specific MW parameters (temperature, pressure, and ramping of temperature) and choice of solvents, researchers can now move into the next generation of advanced nanomaterial design and development. Microwave-assisted chemical reactions are now well-established practices in the laboratory setting although some controversy lingers as to how MW irradiation is able to enhance or influence the outcome of chemical reactions. Much of the discussion has focused on whether the observed effects can, in all instances, be rationalized by purely thermal Arrhenius-based phenomena (thermal microwave effects), that is, the importance of the rapid heating and high bulk reaction temperatures that are achievable using MW dielectric heating in sealed reaction vessels, or whether these observations can be explained by so-called "nonthermal" or "specific microwave" effects. In recent years, innovative and significant advances have occurred in MW hardware development to help delineate MW effects, especially the use of silicon carbide (SiC) reaction vessels and the accurate measurement of temperature using fiber optic (FO) temperature probes. SiC reactors appear to be good alternatives to MW transparent borosilicate glass, because of their high microwave absorptivity, and as such they serve as valuable tools to demystify the claimed magical MW effects. This enables one to evaluate the influence of the electromagnetic field on the specific chemical reactions, under truly identical conventional heating

  6. Is Single-Molecule Fluorescence Spectroscopy Ready To Join the Organic Chemistry Toolkit? A Test Case Involving Click Chemistry.

    PubMed

    Scaiano, Juan C; Lanterna, Anabel E

    2017-04-06

    Single molecule spectroscopy (SMS) has matured to a point where it can be used as a convenient tool to guide organic synthesis and drug discovery, particularly applicable to catalytic systems where questions related to homogeneous vs heterogeneous pathways are important. SMS can look at intimate mechanistic details that can inspire major improvements of the catalyst performance, its recovery, and reuse. Here, we use the click reaction between alkynes and azides as an example where improvements at the bench have been inspired and validated using single-molecule fluorescence spectroscopy.

  7. Modulating the rate of charge transport in a metal-organic framework thin film using host:guest chemistry.

    PubMed

    Hod, Idan; Farha, Omar K; Hupp, Joseph T

    2016-01-28

    Herein we demonstrate the use of host-guest chemistry to modulate rates of charge transport in metal-organic framework (MOF) films. The kinetics of site-to-site of charge hopping and, in turn, the overall redox conductivity, of a ferrocene-modified MOF can be altered by up to 30-fold by coupling electron exchange to the oxidation-state-dependent formation of inclusion complexes between cyclodextrin and channel-tethered metallocenes.

  8. Wet Chemistry on SAM: How it Helps to Detect Organics on Mars

    NASA Astrophysics Data System (ADS)

    Buch, Arnaud; Freissinet, Caroline; Szopa, Cyril; Glavin, Danny; Coll, Patrice; Cabane, Michel; Eigenbrode, Jen; Navarro-Gonzalez, Rafael; Stern, Jen; Coscia, David; Teinturier, Samuel; Dworkin, Jason; Mahaffy, Paul; MSL Science Team

    2013-04-01

    For the first time in the history of space exploration, a mission of interest to astrobiology could be able to analyze refractory organic compounds in the soil of Mars with wet chemistry. This analytical technique modifies organic components in such a way that improves their detection, either by releasing the compounds from sample matrices, or by changing the chemical structure to be amenable to analytical conditions. The latter effect is particularly important when polar compounds are present. Sample Analysis at Mars (SAM), on the Curiosity rover of the Mars Science Laboratory mission, onboards two wet chemistry experiments: derivatization [1-2] and thermochemolysis [3-4]. Here we report on the nature of the MTBSTFA derivatization experiment in SAM, the detection of MTBSTFA in the first SAM analyzes, and the implications of this detection. Chemical derivatization of polar molecular compounds is achieved by the MTBSTFA (N-Methyl-N-tert-butyldimethylsilyltrifluoroacetamide) / DMF (Dimethylformamide) silylation reaction in order to transform refractory polar compounds into a more volatile form that can be analyzed and detected by GCMS. The first samples of Martian soil (Rocknest, Gale crater) have been analyzed by evolved gas analysis (EGA) and via GC using thermal conductivity (TCD) and MS detection. The samples have been heated up to approximately 840°C with a heating rate of 35°C/min under He flow. The evolved gas was analyzed directly by the QMS in EGA mode. For GC analyses, the majority of the gas released was trapped on a hydrocarbon trap (silica beads, Tenax TA, Carbosieve G) over a specific temperature range. Trapped volatiles were then released by heating the trap to ~300 °C and sent to the GC under He flow. The first results obtained when running an analysis with an empty cup (no solid sample) showed the presence of MTBSTFA in the system. MTBSTFA was first detected in the EGA-QMS analysis blank then by GC-TCD-QMS analysis. This means that MTBSTFA is part

  9. Identification of nitrogenous organic species in Titan aerosols analogs: Implication for prebiotic chemistry on Titan and early Earth

    NASA Astrophysics Data System (ADS)

    He, Chao; Smith, Mark A.

    2014-08-01

    Titan has a significant atmosphere composed primarily of nitrogen and methane with a significant organic haze component. Its nitrogen-rich atmosphere, abundant organics, and liquid surface make this moon of interest as a prebiotic laboratory at the planetary scale and one of the best targets for studying prebiotic planetary organic chemistry. In our previous work, we have investigated the chemical composition of Titan aerosol analogs (tholins) and identified a variety of nitrogenous organic molecules. Here we continue our structural investigation and identify four important prebiotic molecules in Titan tholins using NMR, GC-MS and standard sample comparison, including aminoacetonitrile, succinonitrile, acetoguanamine and adenine. On the basis of their structural characteristics, we suggest their formation pathways via simple precursors including methanimine (CH2NH), HCN, NH3, CH3CN and C2H2 in laboratory N2sbnd CH4 plasma or potentially in Titan’s atmosphere. Among these molecules, aminoacetonitrile is a potential precursor of amino acids and peptides, while adenine is a necessary ingredient for DNA and RNA. The identification of these molecules in Titan’s organic aerosol analogs increases our knowledge of Titan’s organic chemistry and its prebiotic implications.

  10. Role of aldehyde chemistry and NOx concentrations in secondary organic aerosol formation

    NASA Astrophysics Data System (ADS)

    Chan, A. W. H.; Chan, M. N.; Surratt, J. D.; Chhabra, P. S.; Loza, C. L.; Crounse, J. D.; Yee, L. D.; Flagan, R. C.; Wennberg, P. O.; Seinfeld, J. H.

    2010-08-01

    Aldehydes are an important class of products from atmospheric oxidation of hydrocarbons. Isoprene (2-methyl-1,3-butadiene), the most abundantly emitted atmospheric non-methane hydrocarbon, produces a significant amount of secondary organic aerosol (SOA) via methacrolein (a C4-unsaturated aldehyde) under urban high-NOx conditions. Previously, we have identified peroxy methacryloyl nitrate (MPAN) as the important intermediate to isoprene and methacrolein SOA in this NOx regime. Here we show that as a result of this chemistry, NO2 enhances SOA formation from methacrolein and two other α, β-unsaturated aldehydes, specifically acrolein and crotonaldehyde, a NOx effect on SOA formation previously unrecognized. Oligoesters of dihydroxycarboxylic acids and hydroxynitrooxycarboxylic acids are observed to increase with increasing NO2/NO ratio, and previous characterizations are confirmed by both online and offline high-resolution mass spectrometry techniques. Molecular structure also determines the amount of SOA formation, as the SOA mass yields are the highest for aldehydes that are α, β-unsaturated and contain an additional methyl group on the α-carbon. Aerosol formation from 2-methyl-3-buten-2-ol (MBO232) is insignificant, even under high-NO2 conditions, as PAN (peroxy acyl nitrate, RC(O)OONO2) formation is structurally unfavorable. At atmospherically relevant NO2/NO ratios (3-8), the SOA yields from isoprene high-NOx photooxidation are 3 times greater than previously measured at lower NO2/NO ratios. At sufficiently high NO2 concentrations, in systems of α, β-unsaturated aldehydes, SOA formation from subsequent oxidation of products from acyl peroxyl radicals+NO2 can exceed that from RO2+HO2 reactions under the same inorganic seed conditions, making RO2+NO2 an important channel for SOA formation.

  11. Role of aldehyde chemistry and NOx concentrations in secondary organic aerosol formation

    NASA Astrophysics Data System (ADS)

    Chan, A. W. H.; Chan, M. N.; Surratt, J. D.; Chhabra, P. S.; Loza, C. L.; Crounse, J. D.; Yee, L. D.; Flagan, R. C.; Wennberg, P. O.; Seinfeld, J. H.

    2010-04-01

    Aldehydes are an important class of products from atmospheric oxidation of hydrocarbons. Isoprene (2-methyl-1,3-butadiene), the most abundantly emitted atmospheric non-methane hydrocarbon, produces a significant amount of secondary organic aerosol (SOA) via methacrolein (a C4-unsaturated aldehyde) under urban high-NOx conditions. Previously, we have identified peroxy methacryloyl nitrate (MPAN) as the important intermediate to isoprene and methacrolein SOA in this NOx regime. Here we show that as a result of this chemistry, NO2 enhances SOA formation from methacrolein and two other α, β-unsaturated aldehydes, specifically acrolein and crotonaldehyde, a NOx effect on SOA formation previously unrecognized. Oligoesters of dihydroxycarboxylic acids and hydroxynitrooxycarboxylic acids are observed to increase with increasing NO2/NO ratio, and previous characterizations are confirmed by both online and offline high-resolution mass spectrometry techniques. Molecular structure also determines the amount of SOA formation, as the SOA mass yields are the highest for aldehydes that are α, β-unsaturated and contain an additional methyl group on the α-carbon. Aerosol formation from 2-methyl-3-buten-2-ol (MBO232) is insignificant, even under high-NO2 conditions, as PAN (peroxy acyl nitrate, RC(O)OONO2) formation is structurally unfavorable. At atmospherically relevant NO2/NO ratios, the SOA yields from isoprene high-NOxphotooxidation are 3 times greater than previously measured at lower NO2/NO ratios. At sufficiently high NO2 concentrations, in systems of α, β-unsaturated aldehydes, SOA formation from subsequent oxidation of products from acyl peroxyl radicals+NO2 can exceed that from RO2+HO2 reactions under the same inorganic seed conditions, making RO2+NO2 an important channel for SOA formation.

  12. Using the QCPE Holdings in Chemical Education: Molecular Models in the Organic Chemistry Laboratory.

    ERIC Educational Resources Information Center

    Lipkowitz, Kenny

    1984-01-01

    Discusses a successfully implemented laboratory experiment that compares the strengths and weaknesses of mechanical and computer models. The computer models used are available from the Quantum Chemistry Program Exchange (QCPE) at a modest price. (JN)

  13. Aerobic Alcohol Oxidation Using a Copper(I)/TEMPO Catalyst System: A Green, Catalytic Oxidation Reaction for the Undergraduate Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Hill, Nicholas J.; Hoover, Jessica M.; Stahl, Shannon S.

    2013-01-01

    Modern undergraduate organic chemistry textbooks provide detailed discussion of stoichiometric Cr- and Mn-based reagents for the oxidation of alcohols, yet the use of such oxidants in instructional and research laboratories, as well as industrial chemistry, is increasingly avoided. This work describes a laboratory exercise that uses ambient air as…

  14. Synthesis and Small Molecule Exchange Studies of a Magnesium Bisformate Metal-Organic Framework: An Experiment in Host-Guest Chemistry for the Undergraduate Laboratory

    ERIC Educational Resources Information Center

    Rood, Jeffrey A.; Henderson, Kenneth W.

    2013-01-01

    concepts of host-guest chemistry and size exclusion in porous metal-organic frameworks (MOFs). The experiment has been successfully carried out in both introductory and advanced-level inorganic chemistry laboratories. Students synthesized the porous MOF, alpha-Mg[subscript…

  15. Chemistry in an inorganic-organic hybrid aerogel: Chitosan-silica aerogel

    NASA Astrophysics Data System (ADS)

    Liu, Xipeng

    2005-11-01

    In this thesis, chemistry in a nanoporous inorganic-organic hybrid aerogel (X-silica aerogel) has been explored. The aerogel typically consisted of 10%w/w bioderived polymer (chitosan), and 90%w/w inorganic silica, which interact at the molecule level. The aerogel has a low density in the range of 0.2--0.3 g/cm3, high surface area in the range of 500--950m 2/g, and large pore volume about 90%. The pores are about 3--5 nm in diameter and the size of the primary particles comprising the aerogel network is about 1.5nm. Chemical studies of X-silica aerogels were carried out in the first instance with organic molecules, including dansyl chloride (DC), succinic anhydride (SA), bis(4-isocynatocyclohexyl) methane (HMDI), and isocyanatoethyl methacrylate (IEMA). These reactions lead to modified X-silica aerogel products imparted with valuable functionalities, including fluorescence, carboxylic acid groups, and pendant isocyanate and methacrylate groups. The functionalized aerogels then were utilized to form novel composites. The isocyanate functionalized aerogels were combined with amine-containing silicone polymers to produce aerogel-silicone polymer composites, and methacrylate functionalized aerogels were reacted with hydroxyethylmethacrylate (HEMA) monomer to produce aerogel-polyHEMA composites. The chemical studies were extended to gold-ion Au(III)-X-silica aerogels. Photoreduction of the Au(IIl)-X-silica aerogels by UV irradiation at 254nm reduced the Au(III) ions into Au(0) nanoparticles (AuNPs) while oxidizing the chitosan. Various sizes of AuNPs, with mean diameters from 8--87nm were obtained by varying the Au(III) ions concentration in aerogels from Au(III)/-NH 2 (-NH2 amine groups on chitosan) ratio 1:120 to 1:5. The intensity and time of exposure to the UV light were varied to explore their effect. Two dimensional patterns of Au(0)-X-silica aerogels were achieved by UV irradiation through a mask. Photo-reduction of Au(III)-X-silica aerogels in the presence of

  16. Mechanisms in Motion-Organic Chemistry Animations v 1.5 (by Bruce H. Lipshutz)

    NASA Astrophysics Data System (ADS)

    Rosan, Alan M.

    1998-08-01

    colors, which aides visualization but may lend the unintended impression that some reactants, intermediates, or products are in antibonding states. A useful adjunct is an indexing guide which links the 17 animations to specific page references in 13 major organic chemistry texts.

  17. Formation of Complex Organic molecules from Formaldehyde Chemistry in Cometary Ice Analogues

    NASA Astrophysics Data System (ADS)

    Duvernay, fabrice; Vinogradoff, Vassilissa; Danger, Grégoire; Theulé, Patrice; Chiavassa, Thierry

    2015-04-01

    There is convincing evidence that the formation of complex organic molecules occurred in a variety of astrophysical environments. Among them, precursors of biomolecules are of particular significance due to their exobiological implications. Hexamethylenetetramine (HMT, C6H12N4) and the polyoxymethylene (POM, -(CH2-O)n-) are of prime interest since they are supposed to be present in cometary environments. They are also ones of the main components of the organic residue formed from the warming of photolysed interstellar/cometary ice analogs. In this work, we study the warming of water-dominated cometary ice analogs containing formaldehyde (H2CO). Based on infrared and mass spectrometry measurements, and complemented by quantum chemical calculations, we report that NH2CH2OH, HOCH2OH, and POM are the only reaction products when the ice also contains NH3. The branching ratio between the three products strongly depends on the initial H2CO/NH3 concentration ratio. Moreover, the influence of the initial ice composition on the formation of POM oligomers (HO-(CH2O)n-H, n<5) as well as their thermal instability between 200 and 320 K are investigated. Finally, the implications of these results with respect to cometary nucleus chemistry and their impact on POM detection by the Rosetta mission are discussed. In addition, the mechanism for HMT formation in interstellar or cometary ice analogs containing H2CO, NH3, and HCOOH has been determined by combining laboratory experiments and DFT calculations. We show that HMT is thermally formed from H2CO and NH3 activated by HCOOH. Two intermediates has been unambiguously detected: NH2CH2OH and the trimer of CH2NH (1,3,5-triazinane, TMT). Unlike to what it was previously thought, HMT is not an indicator of ice photochemistry, but an indicator of thermal processing of ice. These results strengthen the hypothesis that HMT and its intermediates should be present in comets, where they may be detected with the COSAC or COSIMA instrument of

  18. Orgo Cards: Organic Chemistry Review (Steven Q. Wang, Babak Razani, Edward J. K. Lee, Jennifer Wu, and William Berkowitz)

    NASA Astrophysics Data System (ADS)

    Gooch, Eugene

    2003-09-01

    Most students are intimidated by the reputation of organic chemistry, while others see the course as nonessential to their career goals. While they usually have the ability to meet the challenge and succeed, many seek any mechanism by which they can pass the course with minimal study time. Products like Orgo Cards pander to such desires and will not be of benefit to the student with mediocre talent or poor motivation. The best students who buy this set may be bright enough to focus on those very well done mechanisms. But remember, there’s nothing in Orgo Cards that isn’t already in a good organic text.

  19. Dust evolution, a global view: III. Core/mantle grains, organic nano-globules, comets and surface chemistry

    PubMed Central

    2016-01-01

    Within the framework of The Heterogeneous dust Evolution Model for Interstellar Solids (THEMIS), this work explores the surface processes and chemistry relating to core/mantle interstellar and cometary grain structures and their influence on the nature of these fascinating particles. It appears that a realistic consideration of the nature and chemical reactivity of interstellar grain surfaces could self-consistently and within a coherent framework explain: the anomalous oxygen depletion, the nature of the CO dark gas, the formation of ‘polar ice’ mantles, the red wing on the 3 μm water ice band, the basis for the O-rich chemistry observed in hot cores, the origin of organic nano-globules and the 3.2 μm ‘carbonyl’ absorption band observed in comet reflectance spectra. It is proposed that the reaction of gas phase species with carbonaceous a-C(:H) grain surfaces in the interstellar medium, in particular the incorporation of atomic oxygen into grain surfaces in epoxide functional groups, is the key to explaining these observations. Thus, the chemistry of cosmic dust is much more intimately related with that of the interstellar gas than has previously been considered. The current models for interstellar gas and dust chemistry will therefore most likely need to be fundamentally modified to include these new grain surface processes. PMID:28083090

  20. Dust evolution, a global view: III. Core/mantle grains, organic nano-globules, comets and surface chemistry

    NASA Astrophysics Data System (ADS)

    Jones, A. P.

    2016-12-01

    Within the framework of The Heterogeneous dust Evolution Model for Interstellar Solids (THEMIS), this work explores the surface processes and chemistry relating to core/mantle interstellar and cometary grain structures and their influence on the nature of these fascinating particles. It appears that a realistic consideration of the nature and chemical reactivity of interstellar grain surfaces could self-consistently and within a coherent framework explain: the anomalous oxygen depletion, the nature of the CO dark gas, the formation of `polar ice' mantles, the red wing on the 3 μm water ice band, the basis for the O-rich chemistry observed in hot cores, the origin of organic nano-globules and the 3.2 μm `carbonyl' absorption band observed in comet reflectance spectra. It is proposed that the reaction of gas phase species with carbonaceous a-C(:H) grain surfaces in the interstellar medium, in particular the incorporation of atomic oxygen into grain surfaces in epoxide functional groups, is the key to explaining these observations. Thus, the chemistry of cosmic dust is much more intimately related with that of the interstellar gas than has previously been considered. The current models for interstellar gas and dust chemistry will therefore most likely need to be fundamentally modified to include these new grain surface processes.

  1. Dust evolution, a global view: III. Core/mantle grains, organic nano-globules, comets and surface chemistry.

    PubMed

    Jones, A P

    2016-12-01

    Within the framework of The Heterogeneous dust Evolution Model for Interstellar Solids (THEMIS), this work explores the surface processes and chemistry relating to core/mantle interstellar and cometary grain structures and their influence on the nature of these fascinating particles. It appears that a realistic consideration of the nature and chemical reactivity of interstellar grain surfaces could self-consistently and within a coherent framework explain: the anomalous oxygen depletion, the nature of the CO dark gas, the formation of 'polar ice' mantles, the red wing on the 3 μm water ice band, the basis for the O-rich chemistry observed in hot cores, the origin of organic nano-globules and the 3.2 μm 'carbonyl' absorption band observed in comet reflectance spectra. It is proposed that the reaction of gas phase species with carbonaceous a-C(:H) grain surfaces in the interstellar medium, in particular the incorporation of atomic oxygen into grain surfaces in epoxide functional groups, is the key to explaining these observations. Thus, the chemistry of cosmic dust is much more intimately related with that of the interstellar gas than has previously been considered. The current models for interstellar gas and dust chemistry will therefore most likely need to be fundamentally modified to include these new grain surface processes.

  2. Substantial secondary organic aerosol formation in a coniferous forest: observations of both day and night time chemistry

    NASA Astrophysics Data System (ADS)

    Lee, A. K. Y.; Abbatt, J. P. D.; Leaitch, W. R.; Li, S.-M.; Sjostedt, S. J.; Wentzell, J. J. B.; Liggio, J.; Macdonald, A. M.

    2015-10-01

    Substantial biogenic secondary organic aerosol (BSOA) formation was investigated in a coniferous forest mountain region at Whistler, British Columbia. A largely biogenic aerosol growth episode was observed, providing a unique opportunity to investigate BSOA formation chemistry in a forested environment with limited influence from anthropogenic emissions. Positive matrix factorization of aerosol mass spectrometry (AMS) measurement identified two types of BSOA (BSOA-1 and BSOA-2), which were primarily generated by gas-phase oxidation of monoterpenes and perhaps sesquiterpenes. The temporal variations of BSOA-1 and BSOA-2 can be explained by gas-particle partitioning in response to ambient temperature and the relative importance of different oxidation mechanisms between day and night. While BSOA-1 will arise from gas-phase ozonolysis and nitrate radical chemistry at night, BSOA-2 is less volatile than BSOA-1 and consists of products formed via gas-phase oxidation by the OH radical and ozone during the day. Organic nitrates produced through nitrate radical chemistry can account for 22-33 % of BSOA-1 mass at night. The mass spectra of BSOA-1 and BSOA-2 have higher values of the mass fraction of m/z 91 (f91) compared to the background organic aerosol, and so f91 is used as an indicator of BSOA formation pathways. A comparison between laboratory studies in the literature and our field observations highlights the potential importance of gas-phase formation chemistry of BSOA-2 type materials that may not be captured in smog chamber experiments, perhaps due to the wall loss of gas-phase intermediate products.

  3. "OrganicPad": An Interactive Freehand Drawing Application for Drawing Lewis Structures and the Development of Skills in Organic Chemistry

    ERIC Educational Resources Information Center

    Cooper, Melanie M.; Grove, Nathaniel P.; Pargas, Roy; Bryfczynski, Sam P.; Gatlin, Todd

    2009-01-01

    Lewis structures are important for learning chemistry as they serve as an essential link between the structure of chemical compounds and their function. Unfortunately, the creation of valid Lewis structures remains an elusive goal for many students. In recent years, several web-based programs have been created that allow students to receive…

  4. The effects of organic matter-mineral interactions and organic matter chemistry on diuron sorption across a diverse range of soils.

    PubMed

    Smernik, Ronald J; Kookana, Rai S

    2015-01-01

    Sorption of non-ionic organic compounds to soil is usually expressed as the carbon-normalized partition coefficient (KOC), because it is assumed that the main factor that influences the amount sorbed is the organic carbon content of the soil. However, KOC can vary by a factor of at least ten across a range of soils. We investigated two potential causes of variation in diuron KOC - organic matter-mineral interactions and organic matter chemistry - for a diverse set of 34 soils from Sri Lanka, representing a wide range of soil types. Treatment with hydrofluoric acid (HF-treatment) was used to concentrate soil organic matter. HF-treatment increased KOC for the majority of soils (average factor 2.4). We attribute this increase to the blocking of organic matter sorption sites in the whole soils by minerals. There was no significant correlation between KOC for the whole soils and KOC for the HF-treated soils, indicating that the importance of organic matter-mineral interactions varied greatly amongst these soils. There was as much variation in KOC across the HF-treated soils as there was across the whole soils, indicating that the nature of soil organic matter is also an important contributor to KOC variability. Organic matter chemistry, determined by solid-state (13)C nuclear magnetic resonance (NMR) spectroscopy, was correlated with KOC for the HF-treated soils. In particular, KOC increased with the aromatic C content (R=0.64, p=1×10(-6)), and decreased with O-alkyl C (R=-0.32, p=0.03) and alkyl C (R=-0.41, p=0.004) content.

  5. Bringing the science of proteins into the realm of organic chemistry: total chemical synthesis of SEP (synthetic erythropoiesis protein).

    PubMed

    Kent, Stephen B H

    2013-11-11

    Erythropoietin, commonly known as EPO, is a glycoprotein hormone that stimulates the production of red blood cells. Recombinant EPO has been described as "arguably the most successful drug spawned by the revolution in recombinant DNA technology". Recently, the EPO glycoprotein molecule has re-emerged as a major target of synthetic organic chemistry. In this article I will give an account of an important body of earlier work on the chemical synthesis of a designed EPO analogue that had full biological activity and improved pharmacokinetic properties. The design and synthesis of this "synthetic erythropoiesis protein" was ahead of its time, but has gained new relevance in recent months. Here I will document the story of one of the major accomplishments of synthetic chemistry in a more complete way than is possible in the primary literature, and put the work in its contemporaneous context.

  6. Ditch blocking, water chemistry and organic carbon flux: evidence that blanket bog restoration reduces erosion and fluvial carbon loss.

    PubMed

    Wilson, Lorraine; Wilson, Jared; Holden, Joseph; Johnstone, Ian; Armstrong, Alona; Morris, Michael

    2011-05-01

    The potential for restoration of peatlands to deliver benefits beyond habitat restoration is poorly understood. There may be impacts on discharge water quality, peat erosion, flow rates and flood risk, and nutrient fluxes. This study aimed to assess the impact of drain blocking, as a form of peatland restoration, on an upland blanket bog, by measuring water chemistry and colour, and loss of both dissolved (DOC) and particulate organic carbon (POC). The restoration work was designed to permit the collection of a robust experimental dataset over a landscape scale, with data covering up to 3 years pre-restoration and up to 3 years post-restoration. An information theoretic approach to data analyses provided evidence of a recovery of water chemistry towards more 'natural' conditions, and showed strong declines in the production of water colour. Drain blocking led to increases in the E4:E6 ratio, and declines in specific absorbance, suggesting that DOC released from blocked drains consisted of lighter, less humic and less decomposed carbon. Whilst concentrations of DOC showed slight increases in drains and streams after blocking, instantaneous yields of both DOC and POC declined markedly in streams over the first year post-restoration. Attempts were made to estimate total annual fluvial organic carbon fluxes for the study site, and although errors around these estimates remain considerable, there is strong evidence of a large reduction in aquatic organic carbon flux from the peatland following drain-blocking. Potential mechanisms for the observed changes in water chemistry and organic carbon release are discussed, and we highlight the need for more detailed information, from more sites, to better understand the full impacts of peatland restoration on carbon storage and release.

  7. Transport of oxidized multi-walled carbon nanotubes through silica based porous media: influences of aquatic chemistry, surface chemistry, and natural organic matter.

    PubMed

    Yang, Jin; Bitter, Julie L; Smith, Billy A; Fairbrother, D Howard; Ball, William P

    2013-12-17

    This paper provides results from studies of the transport of oxidized multi-walled carbon nanotubes (O-MWCNTs) of varying surface oxygen concentrations under a range of aquatic conditions and through uniform silica glass bead media. In the presence of Na(+), the required ionic strength (IS) for maximum particle attachment efficiency (i.e., the critical deposition concentration, or CDC) increased as the surface oxygen concentration of the O-MWCNTs or pH increased, following qualitative tenets of theories based on electrostatic interactions. In the presence of Ca(2+), CDC values were lower than those with Na(+) present, but were no longer sensitive to surface oxygen content, suggesting that Ca(2+) impacts the interactions between O-MWCNTs and glass beads by mechanisms other than electrostatic alone. The presence of Suwannee River natural organic matter (SRNOM) decreased the attachment efficiency of O-MWCNTs in the presence of either Na(+) or Ca(2+), but with more pronounced effects when Na(+) was present. Nevertheless, low concentrations of SRNOM (<4 mg/L of dissolved organic carbon) were sufficient to mobilize all O-MWCNTs studied at CaCl2 concentrations as high as 10 mM. Overall, this study reveals that NOM content, pH, and cation type show more importance than surface chemistry in affecting O-MWCNTs deposition during transport through silica-based porous media.

  8. Inverted Teaching: Applying a New Pedagogy to a University Organic Chemistry Class

    ERIC Educational Resources Information Center

    Christiansen, Michael A.

    2014-01-01

    Inverted teaching, not to be confused with hybrid learning, is a relatively new pedagogy in which lecture is shifted outside of class and traditional homework is done in class. Though some inverted teaching (IT) designs have been published in different fields, peer-reviewed reports in university chemistry remain quite rare. To that end, herein is…

  9. Using a Tablet PC to Enhance Student Engagement and Learning in an Introductory Organic Chemistry Course

    ERIC Educational Resources Information Center

    Derting, Terry L.; Cox, James R.

    2008-01-01

    Over the past three decades, computer-based technologies have influenced all aspects of chemistry, including chemical education. Pen-based computing applications, such as the tablet PC, have reemerged in the past few years and are providing new ways for educators to deliver content and engage students inside and outside the classroom and…

  10. Greener "Solutions" for the Organic Chemistry Teaching Lab: Exploring the Advantages of Alternative Reaction Media

    ERIC Educational Resources Information Center

    McKenzie, Lallie C.; Huffman, Lauren M.; Hutchison, James E.; Rogers, Courtney E.; Goodwin, Thomas E.; Spessard, Gary O.

    2009-01-01

    A major approach for implementing green chemistry is the discovery and development of synthetic strategies that reduce the quantity of solvent needed, eliminate it altogether, or rely on new reaction media. An increasing number of examples have demonstrated that greener reaction solvents or media can enhance performance as well as reduce hazard.…

  11. Sustaining Change in Upper Level Courses: Peer-Led Workshops in Organic Chemistry and Biochemistry

    ERIC Educational Resources Information Center

    Platt, Terry; Roth, Vicki; Kampmeier, Jack A.

    2008-01-01

    Our peer-led collaborative learning groups, called Workshops, have now had extended success in two upper-level courses in chemistry and biochemistry. These Workshops are in turn supported by a third upper-level course for training peer-leaders. Our data confirm that the initial positive results from the introduction of Workshops in organic…

  12. Connecting Biology and Organic Chemistry Introductory Laboratory Courses through a Collaborative Research Project

    ERIC Educational Resources Information Center

    Boltax, Ariana L.; Armanious, Stephanie; Kosinski-Collins, Melissa S.; Pontrello, Jason K.

    2015-01-01

    Modern research often requires collaboration of experts in fields, such as math, chemistry, biology, physics, and computer science to develop unique solutions to common problems. Traditional introductory undergraduate laboratory curricula in the sciences often do not emphasize connections possible between the various disciplines. We designed an…

  13. Filtrates and Residues: Saturated and Unsaturated Fats: An Organic Chemistry Demonstration.

    ERIC Educational Resources Information Center

    Broniec, Rick

    1985-01-01

    Background information and procedures are provided for an experiment in which an oxidation reaction is used to distinguish saturated from unsaturated fats. Results of the experiment lead to discussions and investigations of such areas as digestion chemistry, enzymes, hydrogenation, and the relationship between heart disease and fat consumption.…

  14. Green, Enzymatic Syntheses of Divanillin and Diapocynin for the Organic, Biochemistry, or Advanced General Chemistry Laboratory

    ERIC Educational Resources Information Center

    Nishimura, Rachel T.; Giammanco, Chiara H.; Vosburg, David A.

    2010-01-01

    Environmentally benign chemistry is an increasingly important topic both in the classroom and the laboratory. In this experiment, students synthesize divanillin from vanillin or diapocynin from apocynin, using horseradish peroxidase and hydrogen peroxide in water. The dimerized products form rapidly at ambient temperature and are isolated by…

  15. A Continuum of Learning: From Rote Memorization to Meaningful Learning in Organic Chemistry

    ERIC Educational Resources Information Center

    Grove, Nathaniel P.; Bretz, Stacey Lowery

    2012-01-01

    The Assimilation Theory of Ausubel and Novak has typically been used in the research literature to describe two extremes to learning chemistry: meaningful learning "versus" rote memorization. It is unlikely, however, that such discrete categories of learning exist. Rote and meaningful learning, rather, are endpoints along a continuum of…

  16. Factors Contributing to Problem-Solving Performance in First-Semester Organic Chemistry

    ERIC Educational Resources Information Center

    Lopez, Enrique J.; Shavelson, Richard J.; Nandagopal, Kiruthiga; Szu, Evan; Penn, John

    2014-01-01

    Problem solving is a highly valued skill in chemistry. Courses within this discipline place a substantial emphasis on problem-solving performance and tend to weigh such performance heavily in assessments of learning. Researchers have dedicated considerable effort investigating individual factors that influence problem-solving performance. The…

  17. Projects that Assist with Content in a Traditional Organic Chemistry Course

    ERIC Educational Resources Information Center

    Esteb, John J.; Magers, John R.; McNulty, LuAnne; Wilson, Anne M.

    2006-01-01

    Two projects, the reaction notebook and the end-of-semester synthesis activity are described which could help students to adopt a discovery-based learning and engage students in practical applications of chemistry. Students have provided positive feedback on this classroom assignment and have felt that it has helped them crystallize their thought…

  18. Organic Chemistry YouTube Writing Assignment for Large Lecture Classes

    ERIC Educational Resources Information Center

    Franz, Annaliese K.

    2012-01-01

    This work describes efforts to incorporate and evaluate the use of a YouTube writing assignment in large lecture classes to personalize learning and improve conceptual understanding of chemistry through peer- and self-explanation strategies. Although writing assignments can be a method to incorporate peer- and self-explanation strategies, this…

  19. Incorporation of the CrossFire Beilstein Database into the Organic Chemistry Curriculum at the Royal Danish School of Pharmacy

    NASA Astrophysics Data System (ADS)

    Brøgger Christensen, S.; Franzyk, Henrik; Frølund, Bente; Jaroszewski, Jerzy W.; Stærk, Dan; Vedsø, Per

    2002-06-01

    The CrossFire Beilstein database has been incorporated into the organic chemistry curriculum at the Royal Danish School of Pharmacy as a powerful pedagogic tool. During a laboratory course in organic synthesis the database enables the students to get comprehensive overviews of known synthetic methods for a given compound. During a laboratory course in identification and as a part of an applied course in organic spectroscopy the students use the database for obtaining lists of all recorded isomeric compounds, facilitating an exhaustive identification. The main entrances for identification purposes are molecular formulas deduced either from titrations or from mass spectra combined with partial structures identified by chemical tests, or by interpretation of spectra. Thus, identifications made using the CrossFire Beilstein database will exclude some possibilities and point to correct structures from a selection of existing compounds. This appears to help the learning process considerably.

  20. A lead user of instruments in science: John D. Roberts and the adaptation of nuclear magnetic resonance to organic chemistry, 1955-1975.

    PubMed

    Reinhardt, Carsten

    2006-06-01

    During the 1960s organic chemistry underwent a spectacular transformation as a result of the introduction of high-tech instruments. In this process, nuclear magnetic resonance (NMR) became an important analytical technique in organic chemistry. The theme of this essay is the relationship of Varian Associates of Palo Alto, California, the major manufacturer of NMR spectrometers up to the 1970s, with one early and crucial user, the organic chemist John D. Roberts, who was based at the California Institute of Technology in Pasadena. Roberts's research and teaching contributed to the fast and smooth acceptance of NMR in organic chemistry. He embraced the role of mediator between the instrument manufacturer, which had expertise mainly in physics and electrical engineering, and the customers, who were mostly organic chemists. This essay focuses on the tactics used by Roberts and James N. Shoolery at Varian Associates to implement novel types of instrumentation and on the modes of cooperation between instrument manufacturer and academic scientist.