WorldWideScience

Sample records for chemistry organic

  1. Organic chemistry

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-08-15

    This book with sixteen chapter explains organic chemistry on linkage isomerism such as alkane, cycloalkane, alkene, aromatic compounds, stereo selective isomerization, aromatic compounds, stereo selective isomerization, organic compounds, stereo selective isomerization, organic halogen compound, alcohol, ether, aldehyde and ketone, carboxylic acid, dicarboxylic acid, fat and detergent, amino, carbohydrate, amino acid and protein, nucleotide and nucleic acid and spectroscopy, a polymer and medical chemistry. Each chapter has introduction structure and characteristic and using of organic chemistry.

  2. Organic chemistry

    International Nuclear Information System (INIS)

    The activities of the mycotoxin research group are discussed. This includes the isolation and structure determination of mycotoxins, plant products, the biosyntheris of mycotoxins, the synthesis and characteristics of steroids, the synthesis and mechanistic aspects of heterocyclic chemistry and the functionality of steroids over long distances. Nmr spectra and mass spectroscopy are some of the techniques used

  3. Organic chemistry experiment

    Energy Technology Data Exchange (ETDEWEB)

    Mun, Seok Sik

    2005-02-15

    This book deals with organic chemistry experiments, it is divided five chapters, which have introduction, the way to write the experiment report and safety in the laboratory, basic experiment technic like recrystallization and extraction, a lot of organic chemistry experiments such as fischer esterification, ester hydrolysis, electrophilic aromatic substitution, aldol reaction, benzoin condensation, wittig reaction grignard reaction, epoxidation reaction and selective reduction. The last chapter introduces chemistry site on the internet and way to find out reference on chemistry.

  4. Online Organic Chemistry

    Science.gov (United States)

    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…

  5. Organic Chemistry in Space

    Science.gov (United States)

    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.

  6. Organic iodine chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Dickinson, S. E-mail: shirley.dickinson@aeat.co.uk; Sims, H.E.; Belval-Haltier, E.; Jacquemain, D.; Poletiko, C.; Funke, F.; Hellmann, S.; Karjunen, T.; Zilliacus, R

    2001-11-01

    A shared-cost action on Organic Iodine Chemistry has been completed as part of the CEC 4th Framework programme on Nuclear Fission Safety. Organisations from four EC countries are involved in an integrated programme of experiments and analysis to help clarify the phenomenology, and to increase confidence in the modelling of iodine behaviour in containment. The project is focused on identifying the main routes for organic iodine formation, and providing new experimental kinetic data which will be used to improve existing models and to stimulate code development.

  7. Organic chemistry on Titan

    Science.gov (United States)

    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.

  8. Organic chemistry in space

    Science.gov (United States)

    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.

  9. Mass spectrometry. [in organic chemistry

    Science.gov (United States)

    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.

  10. Titan's organic chemistry

    Science.gov (United States)

    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.

  11. Organic chemistry on solid surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Zhen; Zaera, Francisco [Department of Chemistry, University of California, Riverside, CA 92521 (United States)

    2006-07-15

    Chemistry on solid surfaces is central to many areas of practical interest such as heterogeneous catalysis, tribology, electrochemistry, and materials processing. With the development of many surface-sensitive analytical techniques in the past decades, great advances have been possible in our understanding of such surface chemistry at the molecular level. Earlier studies with model systems, single crystals in particular, have provided rich information about the adsorption and reaction kinetics of simple inorganic molecules. More recently, the same approach has been expanded to the study of the surface chemistry of relatively complex organic molecules, in large measure in connection with the selective synthesis of fine chemicals and pharmaceuticals. In this report, the chemical reactions of organic molecules and fragments on solid surfaces, mainly on single crystals of metals but also on crystals of metal oxides, carbides, nitrides, phosphides, sulfides and semiconductors as well as on more complex models such as bimetallics, alloys, and supported particles, are reviewed. A scheme borrowed from the organometallic and organic chemistry literature is followed in which key examples of representative reactions are cited first, and general reactivity trends in terms of both the reactants and the nature of the surface are then identified to highlight important mechanistic details. An attempt has been made to emphasize recent advances, but key earlier examples are cited as needed. Finally, correlations between surface and organometallic and organic chemistry, the relevance of surface reactions to applied catalysis and materials functionalization, and some promising future directions in this area are briefly discussed. (author)

  12. Interstellar organic chemistry.

    Science.gov (United States)

    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.

  13. Perspectives on Computational Organic Chemistry

    Science.gov (United States)

    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

  14. Organic Chemistry of Meteorites

    Science.gov (United States)

    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.

  15. Organic chemistry in meteorites

    Science.gov (United States)

    Botta, Oliver

    2002-11-01

    Carbonaceous chondrites contain a suite of soluble organic compounds that possess characteristics that help to understand their formation and to trace back the early history of the solar system. Relative amino acid abundances can be used to discriminate between different parent bodies. The Tagish Lake meteorite is a unique sample from a new type of solar system object that will help to further constrain the physical and chemical conditions found on parent bodies. Enantiomeric excesses have been detected in nonbiological amino acids in the Murchison and Murray meteorites that are still difficult to explain in the current scenario for the synthesis of extraterrestrial amino acids. Finally, new classes of compounds, dipeptides and sugar-related molecules, have been detected in CM carbonaceous chondrites.

  16. Microwaves in organic chemistry and organic chemical

    OpenAIRE

    Mijin Dušan Ž.; Petrović Slobodan D.

    2005-01-01

    The usual way of applying heat to a chemical reaction is the use of a Bunsen burner, an oil or some other type of bath, or an electric heater. In inorganic chemistry, microwave technology has been used since the late 1970s while it has been implemented in organic chemistry since the mid-1980s. Microwave heating has been used in the food industry for almost fifty years. The shorter reaction times and expanded reaction range that is offered by microwave technology are suited to the increased de...

  17. Photoredox Catalysis in Organic Chemistry

    Science.gov (United States)

    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

  18. Photoredox Catalysis in Organic Chemistry.

    Science.gov (United States)

    Shaw, Megan H; Twilton, Jack; MacMillan, David W C

    2016-08-19

    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

  19. Photoredox Catalysis in Organic Chemistry.

    Science.gov (United States)

    Shaw, Megan H; Twilton, Jack; MacMillan, David W C

    2016-08-19

    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.

  20. From organic chemistry to fat and oil chemistry*

    OpenAIRE

    Deffense Etienne

    2009-01-01

    With his work on animal fat and identification of fatty acids, Chevreul was a pioneer in organic chemistry. As Chevreul, I had a passion for organic chemistry too. It was then, an honour and a pleasure to present in 2008 at EFL in Athens this presentation entitled “From organic chemistry to fat and oil chemistry” because my background in organic chemistry helped me all along my professional career to understand and implement new developments related to oil and fat technology and processing. A...

  1. Reaction-Map of Organic Chemistry

    Science.gov (United States)

    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.

  2. Organic chemistry of elemental phosphorus

    Energy Technology Data Exchange (ETDEWEB)

    Milyukov, V A; Budnikova, Yulia H; Sinyashin, Oleg G [A.E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Scientific Centre of the Russian Academy of Sciences, Kazan (Russian Federation)

    2005-09-30

    The principal achievements and the modern trends in the development of the chemistry of elemental phosphorus are analysed, described systematically and generalised. The possibilities and advantages of the preparation of organophosphorus compounds directly from white phosphorus are demonstrated. Attention is focused on the activation and transformation of elemental phosphorus in the coordination sphere of transition metal complexes. The mechanisms of the reactions of white phosphorus with nucleophilic and electrophilic reagents are discussed. Electrochemical approaches to the synthesis of organic phosphorus derivatives based on white phosphorus are considered.

  3. From organic chemistry to fat and oil chemistry*

    Directory of Open Access Journals (Sweden)

    Deffense Etienne

    2009-01-01

    Full Text Available With his work on animal fat and identification of fatty acids, Chevreul was a pioneer in organic chemistry. As Chevreul, I had a passion for organic chemistry too. It was then, an honour and a pleasure to present in 2008 at EFL in Athens this presentation entitled “From organic chemistry to fat and oil chemistry” because my background in organic chemistry helped me all along my professional career to understand and implement new developments related to oil and fat technology and processing. Among the topics which I worked out, I highlighted more particularly the following subjects: the degumming chemistry of oil and fat; the improvement of physical refining; a new chemical analytical tool for the dry fractionation; new development in the dry fractionation

  4. Chemistry of Covalent Organic Frameworks.

    Science.gov (United States)

    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.

  5. Incorporation of Medicinal Chemistry into the Organic Chemistry Curriculum

    Science.gov (United States)

    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.

  6. Microwaves in organic chemistry and organic chemical

    Directory of Open Access Journals (Sweden)

    Mijin Dušan Ž.

    2005-01-01

    Full Text Available The usual way of applying heat to a chemical reaction is the use of a Bunsen burner, an oil or some other type of bath, or an electric heater. In inorganic chemistry, microwave technology has been used since the late 1970s while it has been implemented in organic chemistry since the mid-1980s. Microwave heating has been used in the food industry for almost fifty years. The shorter reaction times and expanded reaction range that is offered by microwave technology are suited to the increased demands in industry. For example, there is a requirement in the pharmaceutical industry for a higher number of a novel chemical entities to be produced, which requires chemists to employ a number of resources to reduce time for the production of compounds. Also, microwaves are used in the food industry, as well as in the pyrolysis of waste materials, sample preparation, the solvent extraction of natural products and the hydrolysis of proteins and peptides.

  7. Statistical Automatic Summarization in Organic Chemistry

    OpenAIRE

    Boudin, Florian; Velazquez-Morales, Patricia; Torres-Moreno, Juan-Manuel

    2009-01-01

    We present an oriented numerical summarizer algorithm, applied to producing automatic summaries of scientific documents in Organic Chemistry. We present its implementation named Yachs (Yet Another Chemistry Summarizer) that combines a specific document pre-processing with a sentence scoring method relying on the statistical properties of documents. We show that Yachs achieves the best results among several other summarizers on a corpus of Organic Chemistry articles.

  8. Understanding Academic Performance in Organic Chemistry

    Science.gov (United States)

    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…

  9. Green chemistry oriented organic synthesis in water.

    Science.gov (United States)

    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. PMID:22048162

  10. Green chemistry oriented organic synthesis in water.

    Science.gov (United States)

    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. 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

    Science.gov (United States)

    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…

  12. A Colorful Solubility Exercise for Organic Chemistry

    Science.gov (United States)

    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…

  13. Plasma chemistry and organic synthesis

    Science.gov (United States)

    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.

  14. Organic chemistry in Titan's atmosphere

    Science.gov (United States)

    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.

  15. The 'wired' universe of organic chemistry.

    Science.gov (United States)

    Grzybowski, Bartosz A; Bishop, Kyle J M; Kowalczyk, Bartlomiej; Wilmer, Christopher E

    2009-04-01

    The millions of reactions performed and compounds synthesized by organic chemists over the past two centuries connect to form a network larger than the metabolic networks of higher organisms and rivalling the complexity of the World Wide Web. Despite its apparent randomness, the network of chemistry has a well-defined, modular architecture. The network evolves in time according to trends that have not changed since the inception of the discipline, and thus project into chemistry's future. Analysis of organic chemistry using the tools of network theory enables the identification of most 'central' organic molecules, and for the prediction of which and how many molecules will be made in the future. Statistical analyses based on network connectivity are useful in optimizing parallel syntheses, in estimating chemical reactivity, and more.

  16. Love Story: Oxygen in Organic Chemistry

    Science.gov (United States)

    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)

  17. Titan: a laboratory for prebiological organic chemistry

    Science.gov (United States)

    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.

  18. State Key Laboratory of Applied Organic Chemistry

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@The State Key Laboratory of Applied Organic Chemistry (SKLAOC) was founded in 1987 with the approval of the State Planning Commission. Professor Liu Zhongli is the director of the Laboratory and Professor Zhang Lihe, an academician of the Chinese Academy of Sciences, is the chairman of its academic committee. There are 30 faculty members, among them 21 are professors, working in the Laboratory.

  19. Organic chemistry: Precision pruning of molecules

    Science.gov (United States)

    Yang, Kin S.; Engle, Keary M.

    2016-05-01

    If organic molecules were trees, then the numerous carbon-hydrogen bonds within them would be leaves. A catalyst that targets one 'leaf' out of many similar other ones looks set to be a huge leap for synthetic chemistry. See Letter p.230

  20. Measuring Student Performance in General Organic Chemistry

    Science.gov (United States)

    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…

  1. Experimental interstellar organic chemistry - Preliminary findings

    Science.gov (United States)

    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.

  2. 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

    Science.gov (United States)

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

    2008-02-01

    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 for the general chemistry students and a basic one for the organic students—to isolate an unknown compound. Then, using spectroscopy (IR and NMR), the students collaborate to determine the structure of the product of the reaction. This application of a standard experiment allows general chemistry students to gain exposure to modern spectroscopic instrumentation and to enhance their problem-solving skills. Organic chemistry students improve their understandings of laboratory techniques and spectroscopic interpretation by acting as the resident experts for the team.

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

    Science.gov (United States)

    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

    Science.gov (United States)

    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.

    Science.gov (United States)

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

    2015-07-01

    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. Physical Organic Chemistry of Supramolecular Polymers

    Science.gov (United States)

    Serpe, Michael J.; Craig, Stephen L.

    2008-01-01

    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. PMID:17279638

  7. Institute of Organic Chemistry: 1983-2008

    OpenAIRE

    Siegel, J S; Heimgartner, H

    2008-01-01

    The developments at the Institute of Organic Chemistry UZH over the past 25 years are discussed with new perspectives being sought through the engagement of a strong international team of professors and the establishment of research groups led by assistant professors. Innovation and change mark the OCI's attitude to the future illustrated by the modern Batchelor's and Master's programs, the 'institute within the institute' the 'Labor für Prozessforschung' (LPF) which uniquely trains post-doct...

  8. Systems chemistry approach in organic photovoltaics.

    Science.gov (United States)

    Würthner, Frank; Meerholz, Klaus

    2010-08-16

    The common approach in organic materials science is dominated by the perception that the properties of the bulk materials are virtually determined by the properties of the molecular building blocks. In this Concept Article, we advocate for taking into account supramolecular organization principles for all kinds of organic solid-state materials, irrespective of them being crystalline, liquid crystalline, or amorphous, and discuss a showcase example, that is, the utilization of merocyanine dyes as p-type organic semiconductors in bulk heterojunction (BHJ) solar cells. Despite their extraordinarily large dipole moments, which are considered to be detrimental for efficient charge carrier transport, BHJ organic photovoltaic materials of these dyes with fullerenes have reached remarkable power conversion efficiencies of meanwhile nearly 5%. These at the first glance contradictory properties are, however, well-understandable on the systems chemistry level.

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

    Science.gov (United States)

    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 entire series…

  10. Synthesis-Spectroscopy Roadmap Problems: Discovering Organic Chemistry

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  12. Atmospheric Chemistry of Micrometeoritic Organic Compounds

    Science.gov (United States)

    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.

  13. Shock-induced chemistry in organic materials

    Energy Technology Data Exchange (ETDEWEB)

    Dattelbaum, Dana M [Los Alamos National Laboratory; Sheffield, Steve [Los Alamos National Laboratory; Engelke, Ray [Los Alamos National Laboratory; Manner, Virginia [Los Alamos National Laboratory; Chellappa, Raja [Los Alamos National Laboratory; Yoo, Choong - Shik [WASHINGTON STATE UNIV

    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.

  14. Novel Aryne Chemistry in Organic Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zhijian [Iowa State Univ., Ames, IA (United States)

    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

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  17. Atmospheric Prebiotic Chemistry and Organic Hazes

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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 typologies were…

  19. Distributed Pore Chemistry in Porous Organic Polymers

    Science.gov (United States)

    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.

  20. Comparing Carbonyl Chemistry in Comprehensive Introductory Organic Chemistry Textbooks

    Science.gov (United States)

    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…

  1. Representational Translation with Concrete Models in Organic Chemistry

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  4. Neural networks for the prediction organic chemistry reactions

    CERN Document Server

    Wei, Jennifer N; Aspuru-Guzik, Alán

    2016-01-01

    Reaction prediction remains one of the great challenges for organic chemistry. Solving this problem computationally requires the programming of a vast amount of knowledge and intuition of the rules of organic chemistry and the development of algorithms for their application. It is desirable to develop algorithms that, like humans, "learn" from being exposed to examples of the application of the rules of organic chemistry. In this work, we introduce a novel algorithm for predicting the products of organic chemistry reactions using machine learning to first identify the reaction type. In particular, we trained deep convolutional neural networks to predict the outcome of reactions based example reactions, using a new reaction fingerprint model. Due to the flexibility of neural networks, the system can attempt to predict reactions outside the domain where it was trained. We test this capability on problems from a popular organic chemistry textbook.

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

    Science.gov (United States)

    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.

  6. Flipping organic chemistry course: Possibilities and challenges

    Science.gov (United States)

    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.

  7. Assessing the impact of integrating POGIL in Elementary Organic Chemistry

    Science.gov (United States)

    Shatila, Ahmad

    Organic chemistry is a difficult subject to teach especially to non-chemistry majors. CHE 251, Elementary Organic Chemistry, is an introductory course in organic chemistry given to non-chemistry majors. It is usually taught the traditional way using lectures as the main method of presentation. In the fall of 2006, POGIL (Process Oriented Guided Inquiry Learning) activities were introduced in this course. POGIL is a program that integrates guided inquiry and cooperative learning in chemistry education. The purpose of this research study was to determine the effect of using POGIL activities in elementary organic chemistry. CHE 251, Elementary Organic Chemistry, was taught using a mixture of traditional teaching, lecturing, and POGIL activities. This was assessed by looking at the effect of using POGIL activities on student achievement. Furthermore, the study investigated possible effects of POGIL activities on students' attitudes toward chemistry. Archival data on 28 students enrolled in the fall 2004 semester were used in this study. In addition, 27 students enrolled in the 2006 semester participated in the study by completing an attitudinal survey that was developed by the researcher. Finally, 9 students enrolled in the 2006 semester were interviewed to give additional insight to the study. The quantitative data concerning achievement revealed no significant difference between groups, students who used POGIL did not differ from students who did not. Further, the quantitative data concerning confidence levels of students in understanding and applying organic chemistry before and after going through the POGIL activities revealed no significant difference. This study showed that students in general (88.8% of surveyed students) liked POGIL activities and preferred them over lecturing. Students thought that POGIL activities helped them better understand and learn chemistry. Furthermore, students acknowledged the benefits of guided inquiry and cooperative learning, the

  8. Nomenclature and Terminology of Organic Chemistry. I. Sixty Years of Croatian Nomenclature of Organic Chemistry

    Directory of Open Access Journals (Sweden)

    Rapić, V.

    2013-07-01

    Full Text Available This article describes the history and development of the Croatian nomenclature of organic chemistry from the publication of the first translation of international nomenclature recommendations to the present age. In the Introduction, trivial, common, systematic (rational, and semisystematic names are defined, and the etymology and meaning of terms nomenclature and terminology are clarified.At the beginning of the central part of this article, attention is focused on the need to create our national nomenclature. The very first such project, initiated by the Croatian Chemical Society (CCS, was the translation of the Geneva (1892 and Lie`ge rules (1930 published in 1954. In 1979 comprehensive general IUPAC rules appeared, and the Croatian Society of Chemical Engineers (CSCE in two volumes printed the Croatian edition of this important document, known as the Blue Book, in 1985 and 1988. A Guide to IUPAC Nomenclature of Organic Compounds (1993 expanded the main principles and rules from the Blue Book, and introduced a higher degree of organic nomenclature systematization. The Croatian translation of the Guide was published in 2002. In the last six decades, almost fifty translations of international rules have been issued, and almost all of them represented the official recommendations of the CCS/CSCE. Finally, the nomenclature in the translations of five comprehensive textbooks fororganic chemistry is analysed.In conclusion, readers are informed that the Croatian version of IUPAC rules is applied in our secondary school and university education, in Croatian encyclopaedism and mass media, as well.

  9. 11(th) National Meeting of Organic Chemistry and 4(th) Meeting of Therapeutic Chemistry.

    Science.gov (United States)

    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

  10. 11th National Meeting of Organic Chemistry and 4th Meeting of Therapeutic Chemistry

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Maria Emília Sousa

    2016-03-01

    Full Text Available 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.

  12. 11(th) National Meeting of Organic Chemistry and 4(th) Meeting of Therapeutic Chemistry.

    Science.gov (United States)

    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.

  13. 11th National Meeting of Organic Chemistry and 4th Meeting of Therapeutic Chemistry

    OpenAIRE

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

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Madronich, Sasha [Univ. Corporation for Atmospheric Research, Boulder, CO (United States)

    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.

  15. A Perspective on Physical Organic Chemistry

    Science.gov (United States)

    2015-01-01

    A perspective on the development of mechanistic carbene chemistry is presented. The author will point out questions that have been answered, and a next generation of questions will be proposed. PMID:24571434

  16. Neural Networks for the Prediction of Organic Chemistry Reactions

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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…

  18. Creatine Synthesis: An Undergraduate Organic Chemistry Laboratory Experiment

    Science.gov (United States)

    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…

  19. Caring for the Environment while Teaching Organic Chemistry

    Science.gov (United States)

    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.

  20. Improvements to the Characterization of Organic Nitrogen Chemistry

    Science.gov (United States)

    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...

  1. Looking forward: a glance into the future of organic chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Compain, Ph.; Desvergnes, V.; Suzenet, F. [Orleans Univ., Institut de Chimie Organique et Analytique, UMR 6005 CNRS, 45 (France); Ollivier, C.; Robert, F.; Mihail, Barboiu; Belmont, Ph.; Bleriot, Y.; Bolze, F.; Bouquillon, S.; Bourguet, E.; Braida, B.; Constantieux, Th.; Desaubry, L.; Dupont, D.; Gastaldi, St.; Jerome, F.; Legoupy, St.; Marat, X.; Migaud, M.; Moitessier, N.; Papot, S.; Peri, F.; Petit, M.; Py, S.; Schulz, E.; Tranoy-Opalinski, I.; Vauzeilles, B.; Vayron, Ph.; Vergnes, L.; Vidal, S.; Wilmouth, S. [Orleans Univ., Institut de Chimie Organique et Analytique, UMR 6005 CNRS, 45 (France)

    2006-06-15

    What will organic chemistry do in the next forty years? This Perspective lists six tasks that have emerged during the first edition of ESYOP, a symposium devoted to the future of organic chemistry. The collective answer presented has been elaborated following a 4-step process: stimulating plenary lectures given by outstanding chemists and philosophers, short presentations given by each participant (average age: 34 years old), think-tank sessions and writing of the final report after the symposium. (authors)

  2. Radiation Chemistry of Organic Liquids: Saturated Hydrocarbons

    CERN Document Server

    Shkrob, Ilya A; Trifunac, A D

    2004-01-01

    In this review (124 refs), several problems in radiolysis of saturated hydrocarbons are examined. Special attention is paid to the chemistry of radical cations, high-mobility holes, excited state and spur dynamics, magnetic field and spin effects, and optically detected magnetic resonance spectroscopy.

  3. Synthesis Road Map Problems in Organic Chemistry

    Science.gov (United States)

    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…

  4. Organic chemistry and biology of the interstellar medium

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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. A Multistep Synthesis for an Advanced Undergraduate Organic Chemistry Laboratory

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  9. Recent advances in the chemistry of organic thiocyanates.

    Science.gov (United States)

    Castanheiro, Thomas; Suffert, Jean; Donnard, Morgan; Gulea, Mihaela

    2016-02-01

    Organic thiocyanates are important synthetic intermediates to access valuable sulfur-containing compounds. In this review the different methods for their preparation and their synthetic applications will be presented. The literature of the last 15 years will be covered, highlighting selected recent advances in the chemistry of this class of compounds. We hope to offer chemists the tools to have a good grasp of this singular functionality and open the door to further progress in this chemistry.

  10. Planetary Organic Chemistry and the Origins of Biomolecules

    OpenAIRE

    Steven A Benner; 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. Unfortunat...

  11. Organic chemistry on Titan: Surface interactions

    Science.gov (United States)

    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.

  12. The Organic Chemistry of Conducting Polymers

    Energy Technology Data Exchange (ETDEWEB)

    Tolbert, Laren Malcolm [Georgia Inst. of Technology, Atlanta, GA (United States)

    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.

  13. Organic chemistry. Strain-release amination.

    Science.gov (United States)

    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.

  14. Organics in environmental ices: sources, chemistry, and impacts

    Directory of Open Access Journals (Sweden)

    D. Voisin

    2012-04-01

    Full Text Available The physical, chemical, and biological processes involving organics in ice in the environment impact a number of atmospheric and biogeochemical cycles. Organic material in snow or ice may be biological in origin, deposited from aerosols or atmospheric gases, or formed chemically in situ. In this manuscript, we review the current state of knowledge regarding the sources, properties, and chemistry of organic materials in environmental ices. Several outstanding questions remain to be resolved and fundamental data gathered before a comprehensive, accurate model of organic species in the cryosphere will be possible. For example, more information is needed regarding the quantitative impacts of chemical and biological processes, ice morphology, and snow formation on the fate of organic material in cold regions. Interdisciplinary work at the interfaces of chemistry, physics and biology is needed in order to fully characterize the nature and evolution of organics in the cryosphere and predict the effects of climate change on the Earth's carbon cycle.

  15. ADVANCES IN ORGANIC, BIOORGANIC AND NATURAL PRODUCTS CHEMISTRY IN THE INSTITUTE OF CHEMISTRY OF THE ACADEMY OF SCIENCES OF MOLDOVA

    OpenAIRE

    Vlad, Pavel F.; Fliur Z. Macaev

    2009-01-01

    This overview deals with the advances in the investigation in the fi eld of organic, bioorganic and naturalproducts chemistry as well as the biologically active compounds in the Institute of Chemistry of the Academy of Sciences of Moldova.

  16. Organic chemistry: No double bond left behind

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

  19. Applications of the Cambridge Structural Database in organic chemistry and crystal chemistry.

    Science.gov (United States)

    Allen, Frank H; Motherwell, W D Samuel

    2002-06-01

    The Cambridge Structural Database (CSD) and its associated software systems have formed the basis for more than 800 research applications in structural chemistry, crystallography and the life sciences. Relevant references, dating from the mid-1970s, and brief synopses of these papers are collected in a database, DBUse, which is freely available via the CCDC website. This database has been used to review research applications of the CSD in organic chemistry, including supramolecular applications, and in organic crystal chemistry. The review concentrates on applications that have been published since 1990 and covers a wide range of topics, including structure correlation, conformational analysis, hydrogen bonding and other intermolecular interactions, studies of crystal packing, extended structural motifs, crystal engineering and polymorphism, and crystal structure prediction. Applications of CSD information in studies of crystal structure precision, the determination of crystal structures from powder diffraction data, together with applications in chemical informatics, are also discussed.

  20. Chemistry: Small molecular replicators go organic

    Science.gov (United States)

    Taylor, Annette F.

    2016-09-01

    The emergence of complex, dynamic molecular behaviour might have had a role in the origin of life. Such behaviour has now been seen in a reaction network involving small, organic, self-replicating molecules of biological relevance. See Letter p.656

  1. Twenty five years of organic chemistry with diiodosamarium

    Energy Technology Data Exchange (ETDEWEB)

    Kagan, Henri B. [Laboratoire de Synthese Asymetrique (UMR 8075), Institut de Chimie Moleculaire et des Materiaux d' Orsay, Universite Paris-Sud, 91405 Orsay (France)]. E-mail: kagan@icmo.u-psud.fr

    2006-02-09

    An historical account of the introduction of samarium diiodide in organic chemistry is presented in the first section, with the main initial results obtained. The basic organic transformations published in the author laboratory and by other groups during the initial period (1977-1987) are detailed. Some of the progresses subsequently obtained will be selected such as various transformations in synthesis, including asymmetric synthesis and total synthesis of natural products. The possible use of SmI{sub 2} in catalytic amount together with a terminal reducing agent is discussed. In the conclusion is summarized the wide scope of the chemistry induced by SmI{sub 2} with some comments on the future of this chemistry.

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  4. Atmospheric Prebiotic Chemistry and Organic Hazes

    OpenAIRE

    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 orga...

  5. Interstellar grain chemistry and organic molecules

    Science.gov (United States)

    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.

  6. Academia–Industry Symbiosis in Organic Chemistry

    Science.gov (United States)

    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

  7. Academia-industry symbiosis in organic chemistry.

    Science.gov (United States)

    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

  8. Academia-industry symbiosis in organic chemistry.

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.)

  10. Integrating Symmetry in Stereochemical Analysis in Introductory Organic Chemistry

    Science.gov (United States)

    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 students--two that…

  11. Synthesis of Bisphenol Z: An Organic Chemistry Experiment

    Science.gov (United States)

    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…

  12. Learning Organic Chemistry through a Study of Semiochemicals

    Science.gov (United States)

    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…

  13. Sudoku Puzzles for First-Year Organic Chemistry Students

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  15. Green chemistry principles in organic compound synthesis and analysis

    Directory of Open Access Journals (Sweden)

    Ruchi Verma

    2014-03-01

    Full Text Available The present review focus on various green chemistry approaches which could be utilized in the organic compounds in practical classes for undergraduate level in comparison of conventional methods. These methods avoid the usage of hazardous substances and are environmental friendly.

  16. An Organic Chemistry Experiment for Forensic Science Majors.

    Science.gov (United States)

    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)

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

    Science.gov (United States)

    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. Several Applications of NMR in Organic Chemistry Research

    Institute of Scientific and Technical Information of China (English)

    CUI yuxin; LIU xuehui; XU hao

    2001-01-01

    @@ Modem NMR techniques, especially 2D-NMR have presented their powerful application in organic chemistry. Not only in structural determination, mechanism investigation, but also in solution conformation study for natural products. In this paper, various pulse field gradient NMR techniques such as COSY, NOESY, HMBC and HMQC were combined to study these problems.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

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

    Directory of Open Access Journals (Sweden)

    Andreas P. Häring

    2015-11-01

    Full Text Available 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.

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

    Science.gov (United States)

    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…

  4. Several Applications of NMR in Organic Chemistry Research

    Institute of Scientific and Technical Information of China (English)

    CUI; yuxin; XU; hao

    2001-01-01

    Modem NMR techniques, especially 2D-NMR have presented their powerful application in organic chemistry. Not only in structural determination, mechanism investigation, but also in solution conformation study for natural products. In this paper, various pulse field gradient NMR techniques such as COSY, NOESY, HMBC and HMQC were combined to study these problems.  ……

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

    Science.gov (United States)

    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. PMID:27559417

  6. Biodiesel Synthesis and Evaluation: An Organic Chemistry Experiment

    Science.gov (United States)

    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…

  7. Biodiesel from Seeds: An Experiment for Organic Chemistry

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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!…

  9. [Lipases in catalytic reactions of organic chemistry].

    Science.gov (United States)

    Bezborodov, A M; Zagustina, N A

    2014-01-01

    Aspects of enzymatic catalysis in lipase-catalyzed reactions of organic synthesis are discussed in the review. The data on modern methods of protein engineering and enzyme modification allowing a broader range of used substrates are briefly summarized. The application of lipase in the preparation of pharmaceuticals and agrochemicals containing no inactive enantiomers and in the synthesis of secondary alcohol enantiomers and optically active amides is demonstrated. The subject of lipase involvement in the C-C bond formation in the Michael reaction is discussed. Data on the enzymatic synthesis of construction materials--polyesters, siloxanes, etc.--are presented. Examples demonstrating the application of lipase enzymatic catalysis in industry are given. PMID:25707112

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

    Science.gov (United States)

    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…

  11. Tc Chemistry in HLW: Role of Organic Complexants

    Energy Technology Data Exchange (ETDEWEB)

    Hess, Nancy S.; Conradsen, Steven D.

    2003-06-01

    Tc complexation with organic compounds in tank waste plays a significant role in the redox chemistry of Tc and the partitioning of Tc between the supernatant and sludge components in waste tanks. These processes need to be understood so that strategies to effectively remove Tc from high-level nuclear waste prior to waste immobilization can be developed and so that long-term consequences of Tc remaining in residual waste after sludge removal can be evaluated. Only limited data on the stability of Tc-organic complexes exists and even less thermodynamic data on which to develop predictive models of Tc chemical behavior is available. To meet these challenges we are conducting a research program to study to develop thermodynamic data on Tc-organic complexation over a wide range of chemical conditions. We will attempt to characterize Tc-speciation in actual tank waste using state-of-the-art analytical organic chemistry, separations, and speciation techniques to validate our model. On the basis of such studies we will develop credible model of Tc chemistry in HLW that will allow prediction of Tc speciation in tank waste and Tc behavior during waste pretreatment processing and in waste tank residuals.

  12. Technetium Chemistry in HLW: Role of Organic Complexants

    Energy Technology Data Exchange (ETDEWEB)

    Hess, Nancy J.; Blanchard, David L., Jr.; Cho, Herman M.; Xia, Yuanxian; Campbell, James A.; Rai, Dhanpat; Conradson, Steven D.

    2004-06-01

    Tc contamination is found within the DOE complex at those sites whose mission involved extraction of plutonium from irradiated uranium fuel or isotopic enrichment of uranium. At the Hanford Site, chemical separations and extraction processes generated large amounts of high level and transuranic wastes that are currently stored in underground tanks. Technetium is thought to have followed U in bismuth phosphate, REDOX and PUREX extraction campaigns and the Cs and Sr isotope recovery efforts. The waste from these extraction processes is currently stored in underground High Level Waste (HLW) tanks. However, the chemistry of the HLW in any given tank is greatly complicated by repeated efforts to reduce volume and recover isotopes. These processes ultimately resulted in mixing of waste streams from different processes. As a result, the chemistry and the fate of Tc in HLW tanks are not well understood. This lack of understanding has been made evident in the failed efforts to leach Tc from sludge and to remove Tc from supernatants prior to immobilization. Although recent interest in Tc chemistry has shifted from pretreatment chemistry to waste residuals, both needs are served by a fundamental understanding of Tc chemistry. The fate of Tc in the insoluble salts that constitute tank residuals is of paramount importance due to the long half-life and environmental mobility of Tc. Knowledge gaps include determination of the Tc oxidation state, the stability of reduced Tc solution species, and interactions with possible organic complexants in HLW. The objective of this renewal proposal is to continue to pursue fundamental understanding of Tc solution chemistry that provides the basis to make knowledgeable decisions and predictions of Tc behavior during retrieval operations and in tank residuals.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  16. Planetary Organic Chemistry and the Origins of Biomolecules

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  19. Spectroscopic diagnostics of organic chemistry in the protostellar environment

    Science.gov (United States)

    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.

  20. Technetium Chemistry in HLW: Role of Organic Complexants

    Energy Technology Data Exchange (ETDEWEB)

    Hess, Nancy J.; Blanchard, David L. Jr.; Campbell, James A.; Cho, Herman M.; Rai, Dhanpat, Rai; Xia, Yuanxian; Conradson, Steven D.

    2002-06-01

    Technetium complexation with organic compounds in tank waste plays a significant role in the redox chemistry of Tc and the partitioning of Tc between the supernatant and sludge components in waste tanks. These processes need to be understood so that strategies to effectively remove Tc from high-level nuclear waste prior to waste immobilization can be developed and so that longterm consequences of Tc remaining in residual waste after sludge removal can be evaluated. Only limited data on the stability of Tc-organic complexes exists, and even less thermodynamic data on which to develop predictive models of Tc chemical behavior is available. To meet these challenges, we present a research program to study Tc-speciation in actual tank waste using state-of-the-art analytical organic chemistry, separations, and speciation techniques. On the basis of such studies, we will acquire thermodynamic data for the identified Tc-organic complexes over a wide range of chemical conditions in order to develop credible models to predict Tc speciation in tank waste and Tc behavior during waste pretreatment processing and in waste tank residuals.

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

    Science.gov (United States)

    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…

  2. ADVANCES IN ORGANIC, BIOORGANIC AND NATURAL PRODUCTS CHEMISTRY IN THE INSTITUTE OF CHEMISTRY OF THE ACADEMY OF SCIENCES OF MOLDOVA

    Directory of Open Access Journals (Sweden)

    Pavel F. Vlad

    2009-06-01

    Full Text Available This overview deals with the advances in the investigation in the fi eld of organic, bioorganic and naturalproducts chemistry as well as the biologically active compounds in the Institute of Chemistry of the Academy of Sciences of Moldova.

  3. Modern electronic structure theory and applications in organic chemistry

    CERN Document Server

    Davidson, ER

    1997-01-01

    This volume focuses on the use of quantum theory to understand and explain experiments in organic chemistry. High level ab initio calculations, when properly performed, are useful in making quantitative distinctions between various possible interpretations of structures, reactions and spectra. Chemical reasoning based on simpler quantum models is, however, essential to enumerating the likely possibilities. The simpler models also often suggest the type of wave function likely to be involved in ground and excited states at various points along reaction paths. This preliminary understanding is n

  4. Directed evolution of aldolases for exploitation in synthetic organic chemistry

    Science.gov (United States)

    Bolt, Amanda; Berry, Alan; Nelson, Adam

    2008-01-01

    This review focuses on the directed evolution of aldolases with synthetically useful properties. Directed evolution has been used to address a number of limitations associated with the use of wild-type aldolases as catalysts in synthetic organic chemistry. The generation of aldolase enzymes with a modified or expanded substrate repertoire is described. Particular emphasis is placed on the directed evolution of aldolases with modified stereochemical properties: such enzymes can be useful catalysts in the stereoselective synthesis of biologically active small molecules. The review also describes some of the fundamental insights into mechanistic enzymology that directed evolution can provide. PMID:18230325

  5. Vial OrganicTM-Organic Chemistry Labs for High School and Junior College

    Science.gov (United States)

    Russo, Thomas J.; Meszaros, Mark

    1999-01-01

    Vial Organic is the most economical, safe, and time-effective method of performing organic chemistry experiments. Activities are carried out in low-cost, sealed vials. Vial Organic is extremely safe because only micro quantities of reactants are used, reactants are contained in tightly sealed vials, and only water baths are used for temperature control. Vial Organic laboratory activities are easily performed within one 50-minute class period. When heat is required, a simple hot-water bath is prepared from a beaker of water and an inexpensive immersion heater. The low cost, ease of use, and relatively short time requirement will allow organic chemistry to be experienced by more students with less confusion and intimidation.

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

    OpenAIRE

    Kolb, Vera M.

    2010-01-01

    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 th...

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

    Science.gov (United States)

    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.

  8. Improving The Organic Chemistry Teaching Learning Process And The Students' English Reading Comprehension

    OpenAIRE

    Srini M. Iskandar

    2016-01-01

    This study was aimed at the improvement of the Organic Chemistry II teaching learning process and the students' English reading comprehension. The design was a two cycled classroom action research whose activities are: in Cycle I the Learning Cycle was implemented using topics taken from an Indonesian Organic Chemistry textbook (Parlan, 2003), and also the Reciprocal Teaching Method using topics taken from an English[ Organic Chemistry textbook (Wade Jr, 1987). In Cycle II both models were im...

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  12. Irradiated Benzene Ice Provides Clues to Meteoritic Organic Chemistry

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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. PMID:27170811

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  4. Sunscreen synthesis and their immobilisation on polymethylmethacrylate: an integrated project in organic chemistry, polymer chemistry and photochemistry

    International Nuclear Information System (INIS)

    Dibenzalacetone and other aldol condensation products are known sunscreens commonly used in cosmetics. This type of compounds can easily be prepared in an Organic Chemistry Lab by reaction of aldehydes with ketones in basic medium. These compounds can be incorporated in poly(methyl methacrylate) and used as UV light absorbers, for example in sunglasses. This project has the advantage of using inexpensive reagents which are readily available in Chemistry Laboratories. This experiment can also be a base starting point for discussions of organic, polymer and photochemistry topics. (author)

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

    Science.gov (United States)

    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

  6. A context based approach using Green Chemistry/Bio-remediation principles to enhance interest and learning of organic chemistry in a high school AP chemistry classroom

    Science.gov (United States)

    Miller, Tricia

    The ability of our planet to sustain life and heal itself is not as predictable as it used to be. Our need for educated future scientists who know what our planet needs, and can passionately apply that knowledge to find solutions should be at the heart of science education today. This study of learning organic chemistry through the lens of the environmental problem "What should be done with our food scraps?" explores student interest, and mastery of certain concepts in organic chemistry. This Green Chemistry/ Bio-remediation context-based teaching approach utilizes the Nature MillRTM, which is an indoor food waste composting machine, to learn about organic chemistry, and how this relates to landfill reduction possibilities, and resource production. During this unit students collected food waste from their cafeteria, and used the Nature MillRTM to convert food waste into compost. The use of these hands on activities, and group discussions in a context-based environment enhanced their interest in organic chemistry, and paper chromatography. According to a one-tailed paired T-test, the result show that this context-based approach is a significant way to increase both student interest and mastery of the content.

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

    Science.gov (United States)

    McNeill, V Faye

    2015-02-01

    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.

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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"…

  11. Iodine-124: A Promising Positron Emitter for Organic PET Chemistry

    Directory of Open Access Journals (Sweden)

    Lena Koehler

    2010-04-01

    Full Text Available 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.

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

    Science.gov (United States)

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

    2010-04-01

    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. PMID:20428073

  13. Exploring organic chemistry in planet-forming zones

    CERN Document Server

    Bast, Jeanette E; van Dishoeck, Ewine F; Tielens, Alexander G G M

    2012-01-01

    Over the last few years, the chemistry of molecules other than CO in the planet-forming zones of disks is starting to be explored with Spitzer and high-resolution ground-based data. However, these studies have focused only on a few simple molecules. The aim of this study is to put observational constraints on the presence of more complex organic and sulfur-bearing molecules predicted to be abundant in chemical models of disks and to simulate high resolution spectra in view of future missions. High S/N Spitzer spectra at 10-30 micron of the near edge-on disks IRS46 and GVTau are used to search for mid-infrared absorption bands of various molecules. These disks are good laboratories because absorption studies do not suffer from low line/continuum ratios that plague emission data. Simple LTE slab models are used to infer column densities (or upper limits) and excitation temperatures. Bands of HCN, C2H2 and CO2 are clearly detected toward both sources. The HCN and C2H2 absorption arises in warm gas with Tex of 40...

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

    Science.gov (United States)

    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…

  15. BIO-ORGANIC CHEMISTRY QUARTERLY REPORT. June through August1963

    Energy Technology Data Exchange (ETDEWEB)

    Various

    1963-10-02

    This report covers the following titles: (1) The Effects of 8-Methyl Lipoic Acid on the Evolution of Oxygen and Reduction of Carbon Dioxide during Photosynthesis; (2) Further {sup 14}C and {sup 15}N Tracer Studies of Amino Acid Synthesis during Photosynthesis by Chlorella Pyrenoidosa; (3) Two-Dimensional High Voltage, Low-Temperature Paper Electrophoresis of {sup 14}C-Labeled Products of Photosynthesis with {sup 14}CO{sub 2}; (4) A Search for Enzymic and Nonenzymic Reactions Between Thiamine Derivatives and Sugar Phosphates; (5) The Cytochrome Content of Purified Spinach Chloroplast Lamellae; (6) The Osmium Tetroxide Fixation of Chloroplast Lamellae; (7) Kinetics of Exoenzymes and Applications to the Determination of the Sequence of Nucleic Acids; (8) Brain Biochemistry and Behavior in Rats; (9) Experiments on Classical Conditioning and Light Habituation in Planarians; (10) Operant Conditioning in Planarians; (11) Manganese Porphyrin Complexes; (12) EPR Studies of Some Complex Organic Solutions; (13) Transient Response of Light-induced Photosynthetic Electron Paramagnetic Resonance Signals: Rhodospirillum rubrum Chromatophores; (14) Studies of the Tautomerism of Amides; (15) Structure and Mechanism of Hydrolysis of the Product of Reaction of PZ05 and Ethyl Ether; (16) A Study of the Irradiation Products of Several Nitrones; (17) Biosynthesis of the Opium Alkaloids; (18) Synthesis of methyl-{beta}-D-thiogalactoside-{sup 35}S; (19) Effect of Acridine Orange and Visible Light on Thymine Dimer Formation and Disruption; (20) Some Aspects of the Radiation Chemistry of DNA; (21) Nuclear Magnetic Resonance; and (22) Studies on the Inhibition of the Photoreduction of FMN.

  16. Microchips in Organics Chemistry: NMR Microcoils for Reaction Monitoring and Computational Chemistry for Microwave-Assisted Reactions

    OpenAIRE

    Rodríguez García, Antonio Manuel

    2014-01-01

    Durante los últimos cuatro años, he estado trabajando en el desarrollo de mi tesis doctoral titulada Microchip in Organic Chemistry: NMR Microcoils for Reaction Monitorization and Computational Chemistry for Microwave-Assisted reactions, realizada bajo la supervisión del Dr. Antonio de la Hoz Ayuso y la Dra. Victoria Gómez Almagro en el área de Química Orgánica en esta facultad. La novedad principal de esta tesis se recoge en un enfoque de resolución de los problemas mediante una perspectiva...

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

    Science.gov (United States)

    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.

  18. Organic carbamates in drug design and medicinal chemistry.

    Science.gov (United States)

    Ghosh, Arun K; Brindisi, Margherita

    2015-04-01

    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.

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

    Science.gov (United States)

    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…

  20. From Polymer to Small Organic Molecules: A Tight Relationship between Radical Chemistry and Solid-Phase Organic Synthesis

    OpenAIRE

    Danilo Mirizzi; Maurizio Pulici

    2011-01-01

    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 dev...

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    OpenAIRE

    Wehle, Sarah; Decker, Michael

    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.

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

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    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...

  11. Operating experience in correcting severe secondary chemistry upsets by controlling makeup water organics (TOC)

    International Nuclear Information System (INIS)

    In this paper following observations are presented: conductivity and chloride excursions in steam condensate were directly linked to makeup water quality. Data strongly suggests that the breakdown of makeup water organics was responsible for substandard condensate water quality; although the short-term effects of gross organic contamination have been documented, the longer term consequences of continuous exposure by moderate organic levels needs to be addressed; a greater understanding of the organic removal efficiency of the various water purification technologies is essential to controlling TOC contamination; and a much better understanding of makeup plant chemistry and the interrelationship of makeup water contamination and plant chemistry has proven essential to optimizing plant performance and guaranteeing the best possible steam chemistry. The role of the chemistry group as an active participant in operations has been proven at Kewaunee Nuclear Plant

  12. Modeling of iodine radiation chemistry in the presence of organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Taghipour, Fariborz; Evans, Greg J. E-mail: evansg@chem-eng.toronto.edu

    2002-06-01

    A kinetic-based model was developed that simulates the radiation chemistry of iodine in the presence of organic compounds. The model's mechanistic description of iodine chemistry and generic semi-mechanistic reactions for various classes of organics, provided a reasonable representation of experimental results. The majority of the model and experimental results of iodine volatilization rates were in agreement within an order of magnitude.

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

  16. Motivational Beliefs and Learning Strategies in Organic Chemistry

    Science.gov (United States)

    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…

  17. Exploring organic chemistry in planet-forming zones

    NARCIS (Netherlands)

    Bast, J. E.; Lahuis, F.; van Dishoeck, E. F.; Tielens, A. G. G. M.

    2013-01-01

    Context. Over the last few years, the chemistry of molecules other than CO in the planet-forming zones of disks is starting to be explored with Spitzer and high-resolution ground-based data. However, these studies have focused only on a few simple molecules. Aims. The aim of this study is to put obs

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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,…

  2. COSMETICS AS THEMATIC TO APPROACH ORGANIC FUNCTIONS IN CHEMISTRY TEACHING

    OpenAIRE

    FREITAS, Tasielle Lima; DA COSTA, Maria Aparecida; FREITAS, Fabricia Carla Ribeiro Mendes; OLIVEIRA, Tatiana de Fátima; MORAES, Lilian Marciolina; FIELD’S, Karla Amâncio Pinto; REZENDE, Gláucia Aparecida Andrade; SANTOS, Renato Gomes

    2016-01-01

    The science teaching has become more complex each passing day regarding its approach in an attempt to promote a more effective content learning, what requires from the teachers reflection concerning their education teaching, aiming at the use of different teaching strategies, such as the approach of chemistry contents through their relation to a social context in which they are inserted, as the use of cosmetics. This paper reports on a pedagogical intervention project in the subject of Sup...

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

    Directory of Open Access Journals (Sweden)

    Vera M. Kolb

    2010-06-01

    Full Text Available 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.

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

    Science.gov (United States)

    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

  5. Combination of organotrifluoroborates with photoredox catalysis marking a new phase in organic radical chemistry.

    Science.gov (United States)

    Koike, Takashi; Akita, Munetaka

    2016-08-01

    Combination of organotrifluoroborates and visible-light-driven photoredox catalysis, both of which have attracted the attention of synthetic chemists, marks a new phase in the field of organic radical chemistry. We have developed photoredox-catalyzed radical reactions with organotrifluoroborates, which turn out to serve not only as a source of organic radicals but also as radical acceptors. The first part of this Perspective deals with the generation of organic radicals from organotrifluoroborates, and the latter part describes addition of the CF3 radical to alkenyltrifluoroborates. The good chemistry between organoborates and photoredox catalysis and its future will be discussed.

  6. Combination of organotrifluoroborates with photoredox catalysis marking a new phase in organic radical chemistry.

    Science.gov (United States)

    Koike, Takashi; Akita, Munetaka

    2016-08-01

    Combination of organotrifluoroborates and visible-light-driven photoredox catalysis, both of which have attracted the attention of synthetic chemists, marks a new phase in the field of organic radical chemistry. We have developed photoredox-catalyzed radical reactions with organotrifluoroborates, which turn out to serve not only as a source of organic radicals but also as radical acceptors. The first part of this Perspective deals with the generation of organic radicals from organotrifluoroborates, and the latter part describes addition of the CF3 radical to alkenyltrifluoroborates. The good chemistry between organoborates and photoredox catalysis and its future will be discussed. PMID:27282517

  7. Chemistry

    International Nuclear Information System (INIS)

    The chemical research and development efforts related to the design and ultimate operation of molten-salt breeder reactor systems are concentrated on fuel- and coolant-salt chemistry, including the development of analytical methods for use in these systems. The chemistry of tellurium in fuel salt is being studied to help elucidate the role of this element in the intergranular cracking of Hastelloy N. Studies were continued of the effect of oxygen-containing species on the equilibrium between dissolved UF3 and dissolved UF4, and, in some cases, between the dissolved uranium fluorides and graphite, and the UC2. Several aspects of coolant-salt chemistry are under investigation. Hydroxy and oxy compounds that could be formed in molten NaBF4 are being synthesized and characterized. Studies of the chemistry of chromium (III) compounds in fluoroborate melts were continued as part of a systematic investigation of the corrosion of structural alloys by coolant salt. An in-line voltammetric method for determining U4+/U3+ ratios in fuel salt was tested in a forced-convection loop over a six-month period. (LK)

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Y. B. Lim

    2015-06-01

    Full Text Available 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Luis R. Domingo

    2016-09-01

    Full Text Available 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.

  18. 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

    Science.gov (United States)

    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…

  19. From Polymer to Small Organic Molecules: A Tight Relationship between Radical Chemistry and Solid-Phase Organic Synthesis

    Directory of Open Access Journals (Sweden)

    Danilo Mirizzi

    2011-04-01

    Full Text Available 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.

  20. The use of chemistry for the synthesis of inorganic-organic hybrid materials

    OpenAIRE

    Schmidt, Helmut K.

    1989-01-01

    The combination between inorganic and organic polymeric materials on nanometer scale depends strongly on methods for synthesizing inorganic polymeric networks suitable to the thermal stability of organic materials. The sol-gel process as a "soft-chemistry" method has been proved to be a proper tool for building up inorganic network with incorporated organic components. Examples for chemical synthesis and material applications are given.

  1. OCCURRENCE & CHEMISTRY OF ORGANIC COMPOUNDS IN HANFORD SITE WASTE TANKS

    Energy Technology Data Exchange (ETDEWEB)

    STOCK, L.M.; MEACHAM, J.E.

    2004-07-29

    Volatile and semivolatile organic compounds continuously evolve from the waste tanks at the Hanford Site. Some are identical to the compounds originally transferred to tanks and others are formed through interdependent chemical and radiolytic reactions. This document provides a technical basis for understanding the chemical consequences of long term storage, sluicing, the addition of chemicals, and the prediction of other organic compounds that may be present in the wastes.

  2. The relevance of metal organic frameworks (MOFs) in inorganic materials chemistry

    Indian Academy of Sciences (India)

    Srinivasan Natarajan; Partha Mahata; Debajit Sarma

    2012-03-01

    The metal organic frameworks (MOFs) have evolved to be an important family and a corner stone for research in the area of inorganic chemistry. The progress made since 2000 has attracted researchers from other disciplines to actively engage themselves in this area. This cooperative synergy of different scientific believes have provided important edge and spread to the chemistry of metal-organic frameworks. The ease of synthesis coupled with the observation of properties in the areas of catalysis, sorption, separation, luminescence, bioactivity, magnetism, etc., are a proof of this synergism. In this article, we present the recent developments in this area.

  3. Volatile organic compound ratios as probes of halogen atom chemistry in the Arctic

    Directory of Open Access Journals (Sweden)

    P. B. Shepson

    2008-03-01

    Full Text Available Volatile organic compound concentration ratios can be used as indicators of halogen chemistry that occurs during ozone depletion events in the Arctic during spring. Here we use a combination of modeling and measurements of [acetone]/[propanal] as an indicator of bromine chemistry, and [isobutane]/[n-butane] and [methyl ethyl ketone]/[n-butane] are used to study the extent of chlorine chemistry during four ozone depletion events during the Polar Sunrise Experiment of 1995. Using a 0-D photochemistry model in which the input of halogen atoms is controlled and varied, the approximate ratio of [Br]/[Cl] can be estimated for each ozone depletion event. It is concluded that there must be an additional source of propanal (likely from the snowpack to correctly simulate the VOC chemistry of the Arctic, and further evidence that the ratio of Br atoms to Cl atoms can vary greatly during ozone depletion events is presented.

  4. Volatile organic compound ratios as probes of halogen atom chemistry in the Arctic

    Directory of Open Access Journals (Sweden)

    A. E. Cavender

    2007-08-01

    Full Text Available Volatile organic compound concentration ratios can be used as indicators of halogen chemistry that occurs during ozone depletion events in the Arctic during spring. Here we use a combination of modeling and measurements of [acetone]/[propanal] as an indicator of bromine chemistry, and [isobutane]/[n-butane] and [methyl ethyl ketone]/[n-butane] are used to study the extent of chlorine chemistry during four ozone depletion events during the Polar Sunrise Experiment of 1995. Using a 0-D photochemistry model in which the input of halogen atoms is controlled and varied, the approximate ratio of [Br]/[Cl] can be estimated for each ozone depletion event. It is concluded that there must be an additional source of propanal (likely from the snowpack to correctly simulate the VOC chemistry of the Arctic, and that the ratio of Br atoms to Cl atoms can vary greatly during ozone depletion events.

  5. mu SR in Organic and Free Radical Chemistry

    CERN Multimedia

    2002-01-01

    Experiment SC82 was begun as a simple attempt to substitute positive muons into polymer molecules, and thereby to use the @mSR technique to study the mechanical relaxation of the different molecular groups. \\\\ \\\\ The experiment has since developed in several directions and has produced a wealth of information on the properties of muonic molecules, and adequately demonstrated the potential of @mSR as applied to molecular physics and chemistry. Physics aspects are now covered by a new experiment code SC95.\\\\ \\\\ The present experiment includes studies where the position occupied by the muon in the molecule (or crystal lattice) is readily established and the @mSR signal is exploited to reveal the intrinsic properties of the material. In this respect the @mSR techniques may be regarded simply as an experimental tool to probe the molecular behaviour of a chemical system. \\\\ \\\\ Two main classes of application include the measurement of isotope effects, where differences between muonic and corresponding photonic radi...

  6. Chemistry

    International Nuclear Information System (INIS)

    Research progress is reported in programs on fuel-salt chemistry, properties of compounds in the Li--Te system, Te spectroscopy UF4--H equilibria, porous electrode studies of molten salts, fuel salt-coolant salt reactions, thermodynamic properties of transition-metal fluorides, and properties of sodium fluoroborate. Developmental work on analytical methods is summarized including in-line analysis of molten MSBR fuel, analysis of coolant-salts for tritium, analysis of molten LiF--BeF2--ThF4 for Fe and analysis of LiF--BeF--ThF4 for Te

  7. Towards a more detailed description of tropospheric aqueous phase organic chemistry: CAPRAM 3.0

    Science.gov (United States)

    Herrmann, H.; Tilgner, A.; Barzaghi, P.; Majdik, Z.; Gligorovski, S.; Poulain, L.; Monod, A.

    CAPRAM 3.0 is the latest development of the chemical aqueous phase radical mechanism (CAPRAM) series which is incorporating CAPRAM 2.4 (Ervens et al., 2003a, Journal of Geophysical Research—Atmospheres 108) and a new extended reaction mechanism for atmospherically relevant hydrocarbons containing more than two and up to six carbon atoms. The chemistry of organics containing three and four carbon atoms is now described in detail. Almost 400 new reactions are now implemented considering the chemistry of organic compounds containing different functional groups, i.e. alcohols, carbonyl compounds, mono- and dicarboxylic acids, polyfunctional compounds as well as some esters and one heterocyclic compound. The aqueous chemistry has been coupled to the gas phase mechanism RACM (regional atmospheric chemistry modeling) (Stockwell et al., 1997, Journal of Geophysical Research—Atmpspheres 102, 25847-25879), and phase exchange is treated using the resistance model of Schwartz (1986. In: Jaeschke, W. (Ed.), Chemistry of Multiphase Atmospheric Systems, NATO ASI Series, Springer, Berlin, pp. 415-471). The CAPRAM remote scenario which was chosen as the standard scenario showed that the introduction of the higher organic chemistry has a relevant influence on the standard subsystems. The diurnal peak concentration of OH radical in the droplets decreases with about 40% and the reactions of OH with hydrocarbons containing 3 or 4 carbon atoms account for about 10% out of the total sinks of OH in the droplets. A slightly stronger acidification of the aqueous phase in comparison to CAPRAM 2.4 is observed. The simulations for the standard scenario showed that there is an increase of organic mass within the droplets where the organic compounds containing 4 carbon atoms represent the 67.5% of the total mass, whereas in the urban and in the marine scenario the contribution of two carbon atom compounds is dominating. The formation and accumulation of substituted mono- and dicarboxylic

  8. Organic nitrogen chemistry during low-grade metamorphism

    Science.gov (United States)

    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

  9. Emergence of complex chemistry on an organic monolayer.

    Science.gov (United States)

    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

  10. Connecting scientific research and classroom instruction: Developing authentic problem sets for the undergraduate organic chemistry curriculum

    Science.gov (United States)

    Raker, Jeffrey R.

    Reform efforts in science education have called for instructional methods and resources that mirror the practice of science. Little research and design methods have been documented in the literature for designing such materials. The purpose of this study was to develop problems sets for sophomore-level organic chemistry instruction. This research adapted an instructional design methodology from the science education literature for the creation of new curricular problem sets. The first phase of this study was to establish an understanding of current curricular problems in sophomore-level organic chemistry instruction. A sample of 792 problems was collected from four organic chemistry courses. These problems were assessed using three literature reported problem typologies. Two of these problem typologies have previously been used to understand general chemistry problems; comparisons between general and organic chemistry problems were thus made. Data from this phase was used to develop a set of five problems for practicing organic chemists. The second phase of this study was to explore practicing organic chemists' experiences solving problems in the context of organic synthesis research. Eight practicing organic chemists were interviewed and asked to solve two to three of the problems developed in phase one of this research. These participants spoke of three problem types: project level, synthetic planning, and day-to-day. Three knowledge types (internal knowledge, knowledgeable others, and literature) were used in solving these problems in research practice and in the developed problems. A set of guiding factors and implications were derived from this data and the chemistry education literature for the conversion of the problems for practicing chemists to problems for undergraduate students. A subsequent conversion process for the five problems occurred. The third, and last phase, of this study was to explore undergraduate students' experiences solving problems in

  11. Do organic surface films on sea salt aerosols influence atmospheric chemistry? ─ a model study

    Directory of Open Access Journals (Sweden)

    R. von Glasow

    2007-11-01

    Full Text Available Organic material from the ocean's surface can be incorporated into sea salt aerosol particles often producing a surface film on the aerosol. Such an organic coating can reduce the mass transfer between the gas phase and the aerosol phase influencing sea salt chemistry in the marine atmosphere. To investigate these effects and their importance for the marine boundary layer (MBL we used the one-dimensional numerical model MISTRA. We considered the uncertainties regarding the magnitude of uptake reduction, the concentrations of organic compounds in sea salt aerosols and the oxidation rate of the organics to analyse the possible influence of organic surfactants on gas and liquid phase chemistry with a special focus on halogen chemistry. By assuming destruction rates for the organic coating based on laboratory measurements we get a rapid destruction of the organic monolayer within the first meters of the MBL. Larger organic initial concentrations lead to a longer lifetime of the coating but lead also to an unrealistically strong decrease of O3 concentrations as the organic film is destroyed by reaction with O3. The lifetime of the film is increased by assuming smaller reactive uptake coefficients for O3 or by assuming that a part of the organic surfactants react with OH. With regard to tropospheric chemistry we found that gas phase concentrations for chlorine and bromine species decreased due to the decreased mass transfer between gas phase and aerosol phase. Aqueous phase chlorine concentrations also decreased but aqueous phase bromine concentrations increased. Differences for gas phase concentrations are in general smaller than for liquid phase concentrations. The effect on gas phase NO2 or NO is very small (reduction less than 5% whereas liquid phase NO2 concentrations increased in some cases by nearly 100%. We list suggestions for further laboratory studies which are needed for improved model studies.

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

    Science.gov (United States)

    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…

  13. Geochemistry and Organic Chemistry on the Surface of Titan

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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)

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

    Science.gov (United States)

    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.

  17. The surface chemistry of metal–organic frameworks

    OpenAIRE

    McGuire, Christina V.; Forgan, Ross S.

    2015-01-01

    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 techni...

  18. Recent advances in the organic chemistry of astatine

    International Nuclear Information System (INIS)

    Investigation on the chemical behaviour of astatine in the last decade are surveyed. The survey covers the physical and chemical properties of astatine, synthesis and identification of organic astatine compounds, their physicochemical properties. A special chapter is devoted to biomedical applications, including inorganic 211At species, 211At-labelled proteins and drugs. An extensive bibliography of the related literature is given. (N.T.) 129 refs.; 12 figs.; 14 tabs

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  4. 2005 Nobel Prize in Chemistry: Development of the Olefin Metathesis Method in Organic Synthesis

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  12. Engaging Organic Chemistry Students Using ChemDraw for iPad

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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,…

  17. Grade/Study-Performance Contracts, Enhanced Communication, Cooperative Learning, and Student Performance in Undergraduate Organic Chemistry.

    Science.gov (United States)

    Dougherty, Ralph C.

    1997-01-01

    Describes and evaluates a teaching strategy, designed to increase student retention while maintaining academic performance levels in undergraduate organic chemistry, that uses grade/study-performance contracts, enhanced communication using electronic mail, and cooperative learning. Concludes that a series of interventions can substantially…

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

    Science.gov (United States)

    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…

  19. Analysis of a Natural Yellow Dye: An Experiment for Analytical Organic Chemistry

    NARCIS (Netherlands)

    Villela, A.; Derksen, G.C.H.; Beek, van T.A.

    2014-01-01

    This experiment exposes second-year undergraduate students taking a course in analytical organic chemistry to high-performance liquid chromatography (HPLC) and quantitative analysis using the internal standard method. This is accomplished using the real-world application of natural dyes for textiles

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  3. Fascinating chemistry or frustrating unpredictability: observations in crystal engineering of metal–organic frameworks

    NARCIS (Netherlands)

    Goesten, M.G.; Kapteijn, F.; Gascon, J.

    2013-01-01

    Reticular design is a highly attractive concept, but coordination chemistry around the tectonic units of metal– organic frameworks (MOFs) and additional interplay with anionic and solvent species provide for dazzling complexity that effectively rules out structure prediction. We can however study th

  4. Manganese (Ⅲ) Acetate:A Versatile Reagent in Organic Chemistry

    Institute of Scientific and Technical Information of China (English)

    Ayhan; S.Demir

    2007-01-01

    1 Results Free radical reactions have become increasingly important,as well as a very attractive tool,in organic synthesis within the last two decades,due to their powerful,selective,specific,and mild reaction abilities.Mn(OAc)3 mediated oxidative free radical reactions have been extensively developed in the last twenty years[1,6].Numerous regio-,chemo-,and stereoselective synthetic methods have been developed in both inter-and intramolecular reactions,and have detailed the progress of Mn(OAc)3 mediated...

  5. Chemistry of Secondary Organic Aerosol Formation From the Reaction of Hydroxyl Radicals With Aromatic Compounds

    OpenAIRE

    Strollo Gordon, Christen Michelle

    2013-01-01

    ABSTRACT OF THE DISSERTATIONChemistry of Secondary Organic Aerosol Formation From the Reaction of Hydroxyl Radicals With Aromatic CompoundsbyChristen Michelle Strollo GordonDoctor of Philosophy, Graduate Program in Chemistry University of California, Riverside, August 2013Dr. Paul J. Ziemann, ChairpersonSecondary Organic Aerosol (SOA) can have significant impacts on visibility, human health, and global climate, and a more detailed understanding of the roles of both gas-phase and heterogeneous...

  6. Correlation of Preadmission Organic Chemistry Courses and Academic Performance in Biochemistry at a Midwest Chiropractic Doctoral Program*

    Science.gov (United States)

    McRae, Marc P.

    2010-01-01

    Purpose: Organic chemistry has been shown to correlate with academic success in the preclinical years of medicine, dentistry, and graduate physiology. The purpose of this study is to examine the relationship between undergraduate organic chemistry grades and first-semester biochemistry grades at a Midwest chiropractic doctoral program. Methods: Students enrolled in a first-semester biochemistry course who had completed the prerequisite courses in organic chemistry offered at this same institution were entered into the study. The total grade for each of the three courses was calculated using the midterm and final exam raw scores with a weighting of 50% each. Analysis consisted of obtaining correlation coefficients between the total grades of organic 1 with biochemistry and organic 2 with biochemistry. Using the biochemistry total grade, the students were divided into quartiles and course grades for both organic chemistry 1 and 2 were calculated. Results: For the 109 students in the study, the correlation coefficient between the biochemistry and organic chemistry 1 and biochemistry and organic chemistry 2 courses was r = 0.744 and r = 0.725, respectively. The difference in organic chemistry grades between those in the first and fourth quartiles was 63.2% and 86.9% for organic chemistry 1 (p < .001) and 60.9% and 79.4% for organic chemistry 2 (p < .001). Conclusion: This study shows that organic chemistry can be used as an indicator of future academic success in a chiropractic biochemistry course. Knowledge of such a relationship could prove useful to identify students who may potentially run into academic difficulty with first-year biochemistry PMID:20480012

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  12. Tholins - Organic chemistry of interstellar grains and gas

    Science.gov (United States)

    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.

  13. Organic chemistry of Murchison meteorite: Carbon isotopic fractionation

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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 .

  15. Role of Synthetic and Dimensional Synthetic Organic Chemistry in Block Copolymer Micelle Nanosensor Engineering

    DEFF Research Database (Denmark)

    Ek, Pramod Kumar

    This thesis investigated the role of amphiphilic triblock copolymer micelle nanomaterials in nanosensors, with emphasis on the synthesis of micelle particle sensors. The thesis is focused on the role of synthetic and dimensional synthetic organic chemistry in amphiphilic triblock core...... micelles. Shell cross-linking on PEG-b-PAEMA-b-PS micelles was performed by amidation reactions between the amino groups of PAEMA blocks using a di-carboxylic acid cross-linker. Also a dendritic cross-linker based click chemistry was used to stabilize the PEG-b-PAEMA-b-PES micelle having click readied PES...

  16. Radon, volatile organic compounds and water chemistry in springs around Popocatepetl volcano, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Segovia, N.; Pena, P.; Lopez, M.B.E.; Cisniega, G. [Inst. Nacional de Investigaciones Nucleares, Mexico D.F. (Mexico); Valdes, C.; Armienta, M.A.; Mena, M. [Inst. de Geofisica, UNAM, Ciudad Univ., Mexico D.F. (Mexico)

    2003-07-01

    Popocatepetl volcano is a high-risk active volcano in Central Mexico where the highest population density in the country is settled. Radon in the soil and groundwater together with water chemistry from samples of nearby springs is analysed as a function of the 2002-2003 volcanic activity. Soil radon indicated fluctuations related both to the meteorological and sporadic explosive events. Groundwater radon showed essentially differences in concentration due to the specific characteristics of the studied springs. Water chemistry showed also stability along the monitoring period indicating differences between springs. No anthropogenic pollution from volatile organic compounds was observed. (orig.)

  17. Celebrating the 60th Anniversary of Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences

    Institute of Scientific and Technical Information of China (English)

    Editorial Office of Chinese Journal of Chemistry

    2010-01-01

    @@ May 2010 is the 60th Anniversary of Shanghai Institute of Organic Chemistry(SIOC),Chinese Academy of Sciences(CAS),the founder and sponsor of Chinese Journal of Chemistry(CJC).In China,a cycle of sixty years forms a so called"jiazi(甲子)",which is the Chinese way of counting years.It is the time that signifies the end of an old cycle and the beginning of a new one.This special issue of CJC is dedicated to SIOC for celebrating her 60th anniversary.

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

    Science.gov (United States)

    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.

  19. 25th anniversary article: progress in chemistry and applications of functional indigos for organic electronics.

    Science.gov (United States)

    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.

  20. Aqueous chemistry and its role in secondary organic aerosol (SOA formation

    Directory of Open Access Journals (Sweden)

    Y. B. Lim

    2010-11-01

    Full Text Available There is a growing understanding that secondary organic aerosol (SOA can form through reactions in atmospheric waters (i.e., clouds, fogs, and aerosol water. In clouds and wet aerosols, water-soluble organic products of gas-phase photochemistry dissolve into the aqueous phase where they can react further (e.g., with OH radicals to form low volatility products that are largely retained in the particle phase. Organic acids, oligomers and other products form via radical and non-radical reactions, including hemiacetal formation during droplet evaporation, acid/base catalysis, and reaction of organics with other constituents (e.g., NH4+.

    This paper provides an overview of SOA formation through aqueous chemistry, including atmospheric evidence for this process and a review of radical and non-radical chemistry, using glyoxal as a model precursor. Previously unreported analyses and new kinetic modeling are reported herein to support the discussion of radical chemistry. Results suggest that reactions with OH radicals tend to be faster and form more SOA than non-radical reactions. In clouds these reactions yield organic acids, whereas in wet aerosols they yield large multifunctional humic-like substances formed via radical-radical reactions and their O/C ratios are near 1.

  1. Chemistry

    International Nuclear Information System (INIS)

    Research and development activities dealing with the chemical problems related to design and ultimate operation of molten-salt reactor systems are described. An experimental test stand was constructed to expose metallurgical test specimens to Te2 vapor at defined temperatures and deposition rates. To better define the chemistry of fluoroborate coolant, several aspects are being investigated. The behavior of hydroxy and oxy compounds in molten NaBF4 is being investigated to define reactions and compounds that may be involved in corrosion and/or could be involved in methods for trapping tritium. Two corrosion products of Hastelloy N, Na3CrF6 and Na5Cr3F14, were identified from fluoroborate systems. The evaluation of fluoroborate and alternate coolants continued. Research on the behavior of hydrogen and its isotopes is summarized. The solubilities of hydrogen, deuterium, and helium in Li2BeF4 are very low. The sorption of tritium on graphite was found to be significant (a few milligrams of tritium per kilogram of graphite), possibly providing a means of sequestering a portion of the tritium produced. Development of analytical methods continued with emphasis on voltammetric and spectrophotometric techniques for the in-line analysis of corrosion products such as Fe2+ and Cr3+ and the determination of the U3+/U4+ ratio in MSBR fuel salt. Similar studies were conducted with the NaBF4--NaF coolant salt. Information developed during the previous operation of the CSTF has been assessed and used to formulate plans for evaluation of in-line analytical methods in future CSTF operations. Electroanalytical and spectrophotometric research suggests that an electroactive protonic species is present in molten NaBF4--NaF, and that this species rapidly equilibrates with a volatile proton-containing species. Data obtained from the CSTF indicated that tritium was concentrated in the volatile species. (JGB)

  2. Flow through reactors for organic chemistry: directly electrically heated tubular mini reactors as an enabling technology for organic synthesis

    Directory of Open Access Journals (Sweden)

    Ulrich Kunz

    2009-11-01

    Full Text Available Until recently traditional heating in organic chemistry has been done with oil heating baths or using electric heat exchangers. With the advent of microwave equipment, heating by microwaves was rapidly introduced as standard method in organic chemistry laboratories, mainly because of the convenient possibility to operate at high temperature accompanied by accelerated reaction rates. In the present contribution we discuss the method of heating small, continuously operated reactors by passing electric current directly through the reactor wall as an enabling technology in organic chemistry. The benefit of this method is that the heat is generated directly inside the reactor wall. By this means high heating rates comparable to microwave ovens can be reached but at much lower cost for the equipment. A tool for the comparison of microwave heating and traditional heating is provided. As an example kinetic data for the acid catalyzed hydrolysis of methyl formate were measured using this heating concept. The reaction is not only a suitable model but also one of industrial importance since this is the main production process for formic acid.

  3. Flow through reactors for organic chemistry: directly electrically heated tubular mini reactors as an enabling technology for organic synthesis.

    Science.gov (United States)

    Kunz, Ulrich; Turek, Thomas

    2009-11-30

    Until recently traditional heating in organic chemistry has been done with oil heating baths or using electric heat exchangers. With the advent of microwave equipment, heating by microwaves was rapidly introduced as standard method in organic chemistry laboratories, mainly because of the convenient possibility to operate at high temperature accompanied by accelerated reaction rates. In the present contribution we discuss the method of heating small, continuously operated reactors by passing electric current directly through the reactor wall as an enabling technology in organic chemistry. The benefit of this method is that the heat is generated directly inside the reactor wall. By this means high heating rates comparable to microwave ovens can be reached but at much lower cost for the equipment. A tool for the comparison of microwave heating and traditional heating is provided. As an example kinetic data for the acid catalyzed hydrolysis of methyl formate were measured using this heating concept. The reaction is not only a suitable model but also one of industrial importance since this is the main production process for formic acid.

  4. Flow through reactors for organic chemistry: directly electrically heated tubular mini reactors as an enabling technology for organic synthesis

    Science.gov (United States)

    Turek, Thomas

    2009-01-01

    Summary Until recently traditional heating in organic chemistry has been done with oil heating baths or using electric heat exchangers. With the advent of microwave equipment, heating by microwaves was rapidly introduced as standard method in organic chemistry laboratories, mainly because of the convenient possibility to operate at high temperature accompanied by accelerated reaction rates. In the present contribution we discuss the method of heating small, continuously operated reactors by passing electric current directly through the reactor wall as an enabling technology in organic chemistry. The benefit of this method is that the heat is generated directly inside the reactor wall. By this means high heating rates comparable to microwave ovens can be reached but at much lower cost for the equipment. A tool for the comparison of microwave heating and traditional heating is provided. As an example kinetic data for the acid catalyzed hydrolysis of methyl formate were measured using this heating concept. The reaction is not only a suitable model but also one of industrial importance since this is the main production process for formic acid. PMID:20300506

  5. An Analysis of Prospective Teachers’ Understanding Levels and Misconceptions in The Subjects of Organic Chemistry: The Case of Alcohols

    Directory of Open Access Journals (Sweden)

    Gulten Sendur

    2013-06-01

    Full Text Available Organic chemistry which is called as chemistry of carbon compounds has an important place in chemistry and other fields of science. The fact that the subject of alcohols in organic chemistry is related to organic compounds such as aldehyde, ketone and carboxylic acid made this subject one of the basic subjects of organic chemistry. For this reason, it was aimed to describe prospective science teachers’ understanding levels and misconceptions about alcohols with this study. In this study, alcohol concept test which includes 16 multiple choice items was applied to 77 prospective science teachers to collect data. In addition, semi-structured interview was conducted with 12 prospective science teachers. At the end of study, it was determined that prospective science teachers had difficulties in understanding some topics such as physical properties of alcohols, structural isomerism, oxidation of alcohols and synthesis of alcohols and they had some misconceptions about these topics.

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

    Science.gov (United States)

    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

  7. Modelling iodide – iodate speciation in atmospheric aerosol: Contributions of inorganic and organic iodine chemistry

    Directory of Open Access Journals (Sweden)

    S. Pechtl

    2007-01-01

    Full Text Available The speciation of iodine in atmospheric aerosol is currently poorly understood. Models predict negligible iodide concentrations but accumulation of iodate in aerosol, both of which is not confirmed by recent measurements. We present an updated aqueous phase iodine chemistry scheme for use in atmospheric chemistry models and discuss sensitivity studies with the marine boundary layer model MISTRA. These studies show that iodate can be reduced in acidic aerosol by inorganic reactions, i.e., iodate does not necessarily accumulate in particles. Furthermore, the transformation of particulate iodide to volatile iodine species likely has been overestimated in previous model studies due to negligence of collision-induced upper limits for the reaction rates. However, inorganic reaction cycles still do not seem to be sufficient to reproduce the observed range of iodide – iodate speciation in atmospheric aerosol. Therefore, we also investigate the effects of the recently suggested reaction of HOI with dissolved organic matter to produce iodide. If this reaction is fast enough to compete with the inorganic mechanism, it would not only directly lead to enhanced iodide concentrations but, indirectly via speed-up of the inorganic iodate reduction cycles, also to a decrease in iodate concentrations. Hence, according to our model studies, organic iodine chemistry, combined with inorganic reaction cycles, is able to reproduce observations. The presented chemistry cycles are highly dependent on pH and thus offer an explanation for the large observed variability of the iodide – iodate speciation in atmospheric aerosol.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    Kanin, Maralee R; Pontrello, Jason K

    2016-03-01

    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. © 2015 by The International Union of Biochemistry and Molecular Biology, 44:168-178, 2016. PMID:26560414

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

    Science.gov (United States)

    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.

  11. 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

    Science.gov (United States)

    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,…

  12. A Química Quântica na compreensão de teorias de Química Orgânica The Quantum Chemistry in the understanding of theories of Organic Chemistry

    Directory of Open Access Journals (Sweden)

    Régis Casimiro Leal

    2010-01-01

    Full Text Available Quantum chemical calculations were performed in order to obtain molecular properties such as electronic density, dipole moment, atomic charges, and bond lengths, which were compared to qualitative results based on the theories of the organic chemistry. The quantum chemistry computational can be a useful tool to support the main theories of the organic chemistry.

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

    OpenAIRE

    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 t...

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

    OpenAIRE

    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

    2016-01-01

    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...

  15. INNOVATION IN ORGANIC CHEMISTRY PRACTICAL WORKS, USING PROBLEM-BASED LEARNING AS TEACHING STRATEGY

    OpenAIRE

    Miriam G. Acuña; Nora M. Sosa; Eusebia C. Valdez

    2011-01-01

    This paper presents the teaching strategy known as problem-based learning as an innovation implemented in the practical experiences of the Organic Chemistry course (Bachelor of Genetics), Faculty of Exact, Chemical and Natural Sciences (Universidad Nacional de Misiones, Argentina). It reviews the results of the experience implemented with students, in groups of 7 selected according to their preferences. A problem that required skills in planning, decision making process, thinking, using of ap...

  16. Role of Synthetic and Dimensional Synthetic Organic Chemistry in Block Copolymer Micelle Nanosensor Engineering

    OpenAIRE

    Ek, Pramod Kumar; Andresen, Thomas Lars; Almdal, Kristoffer

    2012-01-01

    This thesis investigated the role of amphiphilic triblock copolymer micelle nanomaterials in nanosensors, with emphasis on the synthesis of micelle particle sensors. The thesis is focused on the role of synthetic and dimensional synthetic organic chemistry in amphiphilic triblock core-shellcorona micelle based ratiometric fluorescence pH nanosensor fabrications. Two synthetic strategies such as post micelle modification and mixed micellisation (co-micellisation) were employed for pH nanosenso...

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

    Science.gov (United States)

    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.

  18. Grade/Performance Contracts, Enhanced Communication, Cooperative Learning and Student Performance in Undergraduate Organic Chemistry

    Science.gov (United States)

    Dougherty, Ralph C.

    1997-06-01

    This paper describes a grade/study-performance contract that was designed to increase student retention while maintaining academic performance levels in undergraduate organic chemistry. The experimental course included enhanced communication using electronic mail, and cooperative learning in addition to grade/study-performance contracts. The objective of the grade/study-performance contract was the development of learning skills with creation of a basis for unobtrusive auditing of performance. The retention rate in the experimental course was 0.82 for the first term and 0.93 for the second term. The overall retention was 0.76. This value was 3.8 times the average retention for the same sequence in the previous five years at the same institution. It was seven standard deviations away from the previous mean. The ACS Organic Chemistry Examination percentile score for the control section was 46+25 (n=117). The corresponding data for the experimental section was 53+23 (n=143). When the course was offered with the same instructor, cooperative learning, e-mail, but no grade/study-performance contract the ACS Exam percentile average 37+29. This represents a drop of 9.9 standard deviations for comparison of the means. We conclude that grade/study-performance contracts can be effective in increasing both student performance and retention in undergraduate organic chemistry.

  19. Tracing chemical genealogy through the archives of the institute of organic chemistry at the University of Zurich

    OpenAIRE

    Finney, N

    2008-01-01

    Aspects of the history of chemists and chemistry in the Institute of Organic Chemistry at the University of Zurich are traced through chemical genealogy and retained samples from the chemical archives. The work of three OCI faculty members (Werner, Karrer and Eugster) who completed their graduate studies in the Institute is highlighted.

  20. What Can We Do about "Parker"? A Case Study of a Good Student Who Didn't "Get" Organic Chemistry

    Science.gov (United States)

    Anderson, Trisha L.; Bodner, George M.

    2008-01-01

    This paper is based on a qualitative study of seven students enrolled in a two-semester organic chemistry course for chemistry and chemical engineering majors that focused on the reasoning the students had used to answer questions on the course exams. Narrative analysis was applied to create case records for each participant that were then…

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

    Science.gov (United States)

    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…

  2. 3D-printed devices for continuous-flow organic chemistry

    OpenAIRE

    Vincenza Dragone; Victor Sans; Rosnes, Mali H; Kitson, Philip J.; Leroy Cronin

    2013-01-01

    We present a study in which the versatility of 3D-printing is combined with the processing advantages of flow chemistry for the synthesis of organic compounds. Robust and inexpensive 3D-printed reactionware devices are easily connected using standard fittings resulting in complex, custom-made flow systems, including multiple reactors in a series with in-line, real-time analysis using an ATR-IR flow cell. As a proof of concept, we utilized two types of organic reactions, imine syntheses and im...

  3. 3D-printed devices for continuous-flow organic chemistry

    Science.gov (United States)

    Dragone, Vincenza; Sans, Victor; Rosnes, Mali H; Kitson, Philip J

    2013-01-01

    Summary We present a study in which the versatility of 3D-printing is combined with the processing advantages of flow chemistry for the synthesis of organic compounds. Robust and inexpensive 3D-printed reactionware devices are easily connected using standard fittings resulting in complex, custom-made flow systems, including multiple reactors in a series with in-line, real-time analysis using an ATR-IR flow cell. As a proof of concept, we utilized two types of organic reactions, imine syntheses and imine reductions, to show how different reactor configurations and substrates give different products. PMID:23766811

  4. 3D-printed devices for continuous-flow organic chemistry

    Directory of Open Access Journals (Sweden)

    Vincenza Dragone

    2013-05-01

    Full Text Available We present a study in which the versatility of 3D-printing is combined with the processing advantages of flow chemistry for the synthesis of organic compounds. Robust and inexpensive 3D-printed reactionware devices are easily connected using standard fittings resulting in complex, custom-made flow systems, including multiple reactors in a series with in-line, real-time analysis using an ATR-IR flow cell. As a proof of concept, we utilized two types of organic reactions, imine syntheses and imine reductions, to show how different reactor configurations and substrates give different products.

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

    Science.gov (United States)

    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.

    Science.gov (United States)

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

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

    2016-04-01

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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. Radon, water chemistry and pollution check by volatile organic compounds in springs around Popocatepetl volcano, Mexico

    Directory of Open Access Journals (Sweden)

    M. Mena

    2005-06-01

    Full Text Available Popocatepetl volcano is a high-risk active volcano in Central Mexico where the highest population density in the country is settled. Radon in the soil and groundwater together with water chemistry from samples of nearby springs were analysed as a function of the 2002-2003 volcanic activity. The measurements of soil radon indicated fluctuations related to both the meteorological and sporadic explosive events. Groundwater radon showed essential differences in concentration due to the specific characteristics of the studied springs. Water chemistry showed also stability along the monitoring period. No anthropogenic pollution from Volatile Organic Compounds (VOCs was observed. An overview of the soil radon behaviour as a function of the volcanic activity in the period 1994-2002 is also discussed.

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

    Directory of Open Access Journals (Sweden)

    Y. B. Lim

    2013-02-01

    Full Text Available 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.

  13. Chemistry and electronic properties of ferromagnetic metal-organic semiconductor interfaces: Fe on CuPc

    Energy Technology Data Exchange (ETDEWEB)

    Aristov, V.Yu. [IFW Dresden, 01069 Dresden (Germany); Institute of Solid State Physics, Russian Academy of Sciences, Chernogolovka, Moscow distr., 142432 (Russian Federation); Molodtsova, O.V.; Knupfer, M. [IFW Dresden, 01069 Dresden (Germany); Ossipyan, Yu.A. [Institute of Solid State Physics, Russian Academy of Sciences, Chernogolovka, Moscow distr., 142432 (Russian Federation); Doyle, B.P. [TASC-INFM Laboratory, Area Science Park - Basovizza, 34012 Trieste (Italy); Department of Physics, University of Johannesburg, PO Box 524, Auckland Park, 2006 (South Africa); Nannarone, S. [TASC-INFM Laboratory, Area Science Park - Basovizza, 34012 Trieste (Italy); Dipartimento di Ingegneria dei Materiali ed Amb., Universita di Modena e Reggio Emilia (Italy)

    2009-12-15

    The chemistry and electronic properties of the interfaces formed between the ferromagnetic metal (Fe) and the model organic semiconductor copper phthalocyanine are investigated in ultra-high vacuum conditions for the case of metal deposition onto the organic molecular thin film. The studies were performed by means of core-level and valence-band high-resolution photoemission electron spectroscopy (PES) as well as near-edge X-ray absorption fine structure using synchrotron radiation. Metal overlayer formation on the top of the organic semiconductor was observed without substantial penetration of deposited metal species into the organic film. At the thin interface layer the ferromagnetic metal shows strong chemical interaction with the nitrogen and carbon of the organic films. Moreover, our results infer that, as a consequence of Fe deposition onto CuPc, central copper atoms of the organic molecules at the interface are reduced from Cu(II) to Cu(I), while Fe atoms are oxidized and/or the ferromagnetic metal replaces this central Cu atom. Further optimization of such an interface is thus required to allow and/or facilitate the injection of spin-polarized carriers into organic semiconductors. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Directory of Open Access Journals (Sweden)

    J. Lee-Taylor

    2011-06-01

    Full Text Available 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 μg 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 δ-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.

  16. The chemistry of the X-7 (organic) loop coolant part I, May 1960 to April 1965

    International Nuclear Information System (INIS)

    The report describes in detail the X-7 coolant chemistry from the start of loop operation in May 1960 to April 1965. During this period the coolant was Santowax OM containing a nominal 30% high boilers or high molecular weight decomposition products. During the first few months of operation it became apparent that there wa.s a serious problem in the fouling of fuel element heat transfer surfaces. This was overcome by continuous purification of the coolant by Attapulgus clay and filters. Since clay purification has been in use, the fouling rate has been less than 0.2 μg.cm-2.h-1 (10 μm per year), the target value for successful operation of an organic cooled power reactor. Control of the fouling promoter chlorine has been accomplished by completely excluding it from the vicinity of the loop. Any which does get into the coolant is removed by a bed of Mg ribbon and Pd pellets. Since such a bed has been in use, the Cl content of the coolant has been less than 3 ppm. Also given in this report are: (a) a brief history of the loop since its inception in 1959. (b) the effect of the clay column on the coolant chemistry. (c) a complete description of the current purification, degas and make-up circuits, (d) a summary of the coolant chemistry during all fuel irradiations. (author)

  17. Radiation and Chemistry in Nuclear Waste: The NOx System and Organic Aging

    International Nuclear Information System (INIS)

    We describe results that advance the understanding of radiation effects in HLW stored at DOE sites. The scientific issues on which we focus include: a. reactions of primary radicals (e-, OH, and H) of water radiolysis with NO3-/NO2-, b. redox chemistry of NOx radicals and ions, c. degradation mechanisms and kinetics of organic components of HLW, and d. interfacial radiolysis effects in aqueous suspensions and at crystalline NaNO3 interfaces. Understanding these effects and the chemical reacations they induce have contributed to resolving safety issues and setting waste management guidelines at Hanford.

  18. Radiation and Chemistry in Nuclear Waste: The NOx System and Organic Aging

    Energy Technology Data Exchange (ETDEWEB)

    Meisel, Daniel; Camaioni, Donald M.; Orlando, Thomas M.

    2001-01-01

    We describe results that advance the understanding of radiation effects in HLW stored at DOE sites. The scientific issues on which we focus include: a) reactions of primary radicals (e-, OH, and H) of water radiolysis with NO3-/NO2-, b) redox chemistry of NOx radicals and ions, c) degradation mechanisms and kinetics of organic components of HLW, and d) interfacial radiolysis effects in aqueous suspensions and at crystalline NaNO3 interfaces. Understanding these effects and the chemical reacations they induce have contributed to resolving safety issues and setting waste management guidelines at Hanford.

  19. The impact of recirculation, ventilation and filters on secondary organic aerosols generated by indoor chemistry

    DEFF Research Database (Denmark)

    Fadeyi, M.O.; Weschler, Charles J.; Tham, K.W.

    2009-01-01

    This study examined the impact of recirculation rates (7 and 14 h(-1)), ventilation rates (1 and 2 h(-1)), and filtration on secondary organic aerosols (SOAs) generated by ozone of outdoor origin reacting with limonene of indoor origin. Experiments were conducted within a recirculating air handling......, but this was more than offset by the increased dilution of SOA derived from ozone-initiated chemistry. The presence of a particle filter (new or used) strikingly lowered SOA number and mass concentrations compared with conditions when no filter was present. Even though the particle filter in this study had only 35...

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

    Science.gov (United States)

    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. Pollution Prevention Plan for the Y-12 Analytical Chemistry Organization Off-Site Union Valley Facility

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. Neural Network Based on Quantum Chemistry for Predicting Melting Point of Organic Compounds

    Institute of Scientific and Technical Information of China (English)

    Juan A. Lazzús

    2009-01-01

    The melting points of organic compounds were estimated using a combined method that includes a backpropagation neural network and quantitative structure property relationship (QSPR) parameters in quantum chemistry. Eleven descriptors that reflect the intermolec-ular forces and molecular symmetry were used as input variables. QSPR parameters were calculated using molecular modeling and PM3 semi-empirical molecular orbital theories. A total of 260 compounds were used to train the network, which was developed using MatLab. Then, the melting points of 73 other compounds were predicted and results were compared to experimental data from the literature. The study shows that the chosen artificial neural network and the quantitative structure property relationships method present an excellent alternative for the estimation of the melting point of an organic compound, with average absolute deviation of 5%.

  3. Organic Chemistry Students' Fragmented Ideas about the Structure and Function of Nucleophiles and Electrophiles: A Concept Map Analysis

    Science.gov (United States)

    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…

  4. Synthesis of 10-Ethyl Flavin: A Multistep Synthesis Organic Chemistry Laboratory Experiment for Upper-Division Undergraduate Students

    Science.gov (United States)

    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…

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. Mechanisms before Reactions: A Mechanistic Approach to the Organic Chemistry Curriculum Based on Patterns of Electron Flow

    Science.gov (United States)

    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…

  7. Synthesis of a Partially Protected Azidodeoxy Sugar. A Project Suitable for the Advanced Undergraduate Organic Chemistry Laboratory

    Science.gov (United States)

    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.

  8. Integration of Computational and Preparative Techniques to Demonstrate Physical Organic Concepts in Synthetic Organic Chemistry: An Example Using Diels-Alder Reaction

    Science.gov (United States)

    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…

  9. Do Long-Term Changes in Organic Matter Inputs to Forest Soils Affect Dissolved Organic Matter Chemistry and Export?

    Science.gov (United States)

    Lajtha, K.; Strid, A.; Lee, B. S.

    2014-12-01

    Dissolved organic matter (DOM) production and transport play an important role in regulating organic matter (OM) distribution through a soil profile and ultimately, OM stabilization or export to aquatic systems. The contributions of varying OM inputs to the quality and amount of DOM as it passes through a soil profile remain relatively unknown. The Detrital Input and Removal Treatment (DIRT) site at the H. J. Andrews Experimental Forest in Oregon has undergone 17 years of litter, wood and root input manipulations and allows us to guage shifts in DOM chemistry induced by long-term changes to aboveground and belowground OM additions and exclusions. Using fluorescence and UV spectroscopy to characterize fluorescent properties, extent of decomposition, and sources of DOM in streams and soil solutions collected with lysimeters and soil extractions, we have assessed the importance of fresh OM inputs to DOM chemistry. Soil extracts from DIRT plots had a higher fluorescence index (FI) than lysimeter solutions or stream water. A high FI in surface water is generally interpreted as indicative of a high proportion of microbially-derived DOM. However, we suspect that the high FI in soil extracts is due to a higher proportion of non-aromatic DOM from fresh soil that microorganisms consume in transit through the soil profile to lysimeters or to streams. High redox index (RI) values were observed in lysimeters from the April 2014 sampling compared with the November 2013 sampling. These RI values show evidence of more reducing conditions at the end of the rainy season in the spring compared to the onset of the rainy season in the fall. Lysimeter water collected in No Input, No Litter, and No Root treatments contained high proportions of protein, suggesting the absence of carbon inputs changes activities of the microbial community. Observed variations reflect the viability of using fluorescent properties to explore the terrestrial-aquatic interface.

  10. Innovation Developments of Coal Chemistry Science in L.M. Litvinenko Institute of Physical-Organic Chemistry and Coal Chemistry of NAS of Ukraine

    Directory of Open Access Journals (Sweden)

    Shendrik, T.G.

    2015-11-01

    Full Text Available The article presents short historical review and innovation developments of Coal Chemistry Department of L.M. Litvinenko Institute, NAS of Ukraine connected with coal mine exploitation problems, search for decisions toward prevention of spontaneous combustion, dust control in mines, establishing structural chemical features of coal with different genesis and stages of metamorphism with the aim to develop new methods of their modification and rational use. The methods of obtaining inexpensive sorbents from Ukrainian raw materials (including carbon containing waste are proposed. The problems of modern coal chemistry science in IPOCC of NAS of Ukraine are outlined.

  11. Oxygenated Organic Chemicals in the Pacific Troposphere: Distribution, Sources and Chemistry

    Science.gov (United States)

    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.

  12. Poster 6: Influence of traces elements in the organic chemistry of upper atmosphere of Titan

    Science.gov (United States)

    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.

  13. Intrinsic charge trapping in organic and polymeric semiconductors: a physical chemistry perspective

    Energy Technology Data Exchange (ETDEWEB)

    Kaake, Loren [Univ. of Texas, Austin, TX (United States); Barbara, Paul F. [Univ. of Texas, Austin, TX (United States); Zhu, Xiaoyang [Univ. of Texas, Austin, TX (United States)

    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.

  14. Chemistry of Mesoporous Organosilica in Nanotechnology: Molecularly Organic-Inorganic Hybridization into Frameworks.

    Science.gov (United States)

    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.

  15. Chemistry of Mesoporous Organosilica in Nanotechnology: Molecularly Organic-Inorganic Hybridization into Frameworks.

    Science.gov (United States)

    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. PMID:26936391

  16. Development and analysis of educational technologies for a blended organic chemistry course

    Science.gov (United States)

    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

  17. Molecular Chemistry of Organic Aerosols Through the Application of High Resolution Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Nizkorodov, Serguei; Laskin, Julia; Laskin, Alexander

    2011-01-05

    Understanding of molecular composition and fundamental chemical transformations of organic aerosols (OA) during their formation and aging is both a major challenge and the area of greatest uncertainty in atmospheric research. Particularly little is known about fundamental relationship between the chemical composition and physicochemical properties of OA, their atmospheric history, evolution, and impact on the environment. Ambient soft-ionization methods combined with high-resolution mass spectrometry (HR-MS) analysis provide detailed information on the molecular content of OA that is pivotal for improved understanding of their complex composition, multi-phase aging chemistry, direct (light absorption and scattering) and indirect (aerosol-cloud interactions) effects on atmospheric radiation and climate, and health effects. The HR-MS methods can detect thousands of individual OA constituents at once, provide their elemental formulae from accurate mass measurements, and provide structural information based on tandem mass spectrometry. Integration with additional analytical tools, such as chromatography and UV/Vis absorption spectroscopy, makes it possible to further separate OA compounds by their polarity and ability to absorb solar radiation. The goal of this perspective is to describe modern HR-MS methods, review recent applications to field and laboratory studies of OA, and explain how the information obtained from HR-MS methods can be translated into improved understanding of OA chemistry.

  18. Synthesis of Organic Matter of Prebiotic Chemistry at the Protoplanetary Disc

    Science.gov (United States)

    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

  19. Introduction of water chemistry conditions of the secondary coolant circuit with metering organic amines at nuclear power stations equipped with VVER-1000 reactors

    Science.gov (United States)

    Tyapkov, V. F.; Erpyleva, S. F.; Bykova, V. V.

    2009-05-01

    Results from introduction of new water chemistry conditions involving metering of organic amines (morpholine and ethanolamine) at nuclear power stations equipped with VVER-1000 reactors are presented.

  20. 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

    Science.gov (United States)

    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.

  1. Chemistry of Metal-organic Frameworks Monitored by Advanced X-ray Diffraction and Scattering Techniques.

    Science.gov (United States)

    Mazaj, Matjaž; Kaučič, Venčeslav; Zabukovec Logar, Nataša

    2016-01-01

    The research on metal-organic frameworks (MOFs) experienced rapid progress in recent years due to their structure diversity and wide range of application opportunities. Continuous progress of X-ray and neutron diffraction methods enables more and more detailed insight into MOF's structural features and significantly contributes to the understanding of their chemistry. Improved instrumentation and data processing in high-resolution X-ray diffraction methods enables the determination of new complex MOF crystal structures in powdered form. By the use of neutron diffraction techniques, a lot of knowledge about the interaction of guest molecules with crystalline framework has been gained in the past few years. Moreover, in-situ time-resolved studies by various diffraction and scattering techniques provided comprehensive information about crystallization kinetics, crystal growth mechanism and structural dynamics triggered by external physical or chemical stimuli. The review emphasizes most relevant advanced structural studies of MOFs based on powder X-ray and neutron scattering. PMID:27640372

  2. Active Learning and Cooperative Learning in the Organic Chemistry Lecture Class

    Science.gov (United States)

    Paulson, Donald R.

    1999-08-01

    Faculty in the physical sciences are one of the academic groups least receptive to the use of active learning strategies and cooperative learning in their classrooms. This is particularly so in traditional lecture classes. It is the objective of this paper to show how effective these techniques can be in improving student performance in classes. The use of active learning strategies and cooperative learning groups in my organic chemistry lecture classes has increased the overall pass rate in my classes by an astounding 20-30% over the traditional lecture mode. This has been accomplished without any reduction in "standards". The actual methods employed are presented as well as a discussion of how I came to radically change the way I teach my classes.

  3. Chemistry of Metal-organic Frameworks Monitored by Advanced X-ray Diffraction and Scattering Techniques.

    Science.gov (United States)

    Mazaj, Matjaž; Kaučič, Venčeslav; Zabukovec Logar, Nataša

    2016-01-01

    The research on metal-organic frameworks (MOFs) experienced rapid progress in recent years due to their structure diversity and wide range of application opportunities. Continuous progress of X-ray and neutron diffraction methods enables more and more detailed insight into MOF's structural features and significantly contributes to the understanding of their chemistry. Improved instrumentation and data processing in high-resolution X-ray diffraction methods enables the determination of new complex MOF crystal structures in powdered form. By the use of neutron diffraction techniques, a lot of knowledge about the interaction of guest molecules with crystalline framework has been gained in the past few years. Moreover, in-situ time-resolved studies by various diffraction and scattering techniques provided comprehensive information about crystallization kinetics, crystal growth mechanism and structural dynamics triggered by external physical or chemical stimuli. The review emphasizes most relevant advanced structural studies of MOFs based on powder X-ray and neutron scattering.

  4. Final Report. IUT No. B560420 with UC Berkeley. Organic Chemistry at High Pressures &Temperatures

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. My maize and blue brick road to physical organic chemistry in materials.

    Science.gov (United States)

    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.

  6. Ionic Liquids Beyond Simple Solvents: Glimpses at the State of the Art in Organic Chemistry.

    Science.gov (United States)

    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.

  7. Distributed Pore Chemistry in Porous Organic Polymers in Tissue Culture Flasks

    Science.gov (United States)

    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.

  8. Computational organic chemistry: bridging theory and experiment in establishing the mechanisms of chemical reactions.

    Science.gov (United States)

    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.

  9. My maize and blue brick road to physical organic chemistry in materials

    Science.gov (United States)

    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

  10. Supramolecular organic frameworks: engineering periodicity in water through host-guest chemistry.

    Science.gov (United States)

    Tian, Jia; Chen, Lan; Zhang, Dan-Wei; Liu, Yi; Li, Zhan-Ting

    2016-05-11

    The development of homogeneous, water-soluble periodic self-assembled structures comprise repeating units that produce porosity in two-dimensional (2D) or three-dimensional (3D) spaces has become a topic of growing interest in the field of supramolecular chemistry. Such novel self-assembled entities, known as supramolecular organic frameworks (SOFs), are the result of programmed host-guest interactions, which allows for the thermodynamically controlled generation of monolayer sheets or a diamondoid architecture with regular internal cavities or pores under mild conditions. This feature article aims at propagating the conceptually novel SOFs as a new entry into conventional supramolecular polymers. In the first section, we will describe the background of porous solid frameworks and supramolecular polymers. We then introduce the self-assembling behaviour of several multitopic flexible molecules, which is closely related to the design of periodic SOFs from rigid multitopic building blocks. This is followed by a brief discussion of cucurbit[8]uril (CB[8])-encapsulation-enhanced aromatic stacking in water. The three-component host-guest pattern based on this stacking motif has been utilized to drive the formation of most of the new SOFs. In the following two sections, we will highlight the main advances in the construction of 2D and 3D SOFs and the related functional aspects. Finally, we will offer our opinions on future directions for both structures and functions. We hope that this article will trigger the interest of researchers in the field of chemistry, physics, biology and materials science, which should help accelerate the applications of this new family of soft self-assembled organic frameworks.

  11. Heterogeneous chemistry and reaction dynamics of the atmospheric oxidants, O3, NO3, and OH, on organic surfaces.

    Science.gov (United States)

    Chapleski, Robert C; Zhang, Yafen; Troya, Diego; Morris, John R

    2016-07-01

    Heterogeneous chemistry of the most important atmospheric oxidants, O3, NO3, and OH, plays a central role in regulating atmospheric gas concentrations, processing aerosols, and aging materials. Recent experimental and computational studies have begun to reveal the detailed reaction mechanisms and kinetics for gas-phase O3, NO3, and OH when they impinge on organic surfaces. Through new research approaches that merge the fields of traditional surface science with atmospheric chemistry, researchers are developing an understanding for how surface structure and functionality affect interfacial chemistry with this class of highly oxidizing pollutants. Together with future research initiatives, these studies will provide a more complete description of atmospheric chemistry and help others more accurately predict the properties of aerosols, the environmental impact of interfacial oxidation, and the concentrations of tropospheric gases.

  12. Effect of Organic Coatings, Humidity and Aerosol Acidity on Multiphase Chemistry of Isoprene Epoxydiols

    Energy Technology Data Exchange (ETDEWEB)

    Riva, Matthieu N.; Bell, David M.; Hansen, Anne Maria K.; Droza, Greg T.; Zhang, Zhenfa; Gold, Avram; Imre, D.; 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.

  13. Dissolved organic matter conformation and its interaction with pyrene as affected by water chemistry and concentration.

    Science.gov (United States)

    Pan, Bo; Ghosh, Saikat; Xing, Baoshan

    2008-03-01

    Water chemistry and concentration of dissolved organic matter (DOM) have been reported to affect DOM conformation and binding properties with hydrophobic organic contaminants (HOCs). However, relationship between DOM conformation and its binding properties remains unclear. We designed a multibag equilibration system (MBES) to investigate the variation of carbon-normalized sorption coefficients (K(DOC)) of pyrene at different DOM concentrations based on an identical free solute concentration at different pHs and in the presence of Al ions. In addition, we studied the conformation of DOM under different conditions via atomic force microscopy (AFM) imaging, dynamic light scattering, and zeta potential measurements. Zeta potential measurements indicated that intra- and intermolecular interaction was facilitated at low pH or with the presence of Al ions, and a more organized molecular aggregate (such as a micelle-like structure) could form, thus, enhancing K(DOC). As DOM concentration increased, DOM molecular aggregation was promoted in a way reducing K(DOC). This research is a first attempt to correlate DOM conformation with K(DOC). Aggregation of DOM molecules resulting from increased zeta potential (less negative) generally led to an increased K(DOC). Further study in this area will provide valuable information on HOC-DOM interactions, thus, leading to more accurate predictions of K(DOC).

  14. Effect of Organic Coatings, Humidity and Aerosol Acidity on Multiphase Chemistry of Isoprene Epoxydiols.

    Science.gov (United States)

    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

    2016-06-01

    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 with AP-derived SOA is lower compared to that of pure ABS particles, strongly dependent on particle composition, and therefore on particle size. PMID:27176464

  15. Quantification and classification of substituent effects in organic chemistry: a theoretical molecular electrostatic potential study.

    Science.gov (United States)

    Remya, Geetha S; Suresh, Cherumuttathu H

    2016-07-27

    Substituent effects in organic chemistry are generally described in terms of experimentally derived Hammett parameters whereas a convenient theoretical tool to study these effects in π-conjugated molecular systems is molecular electrostatic potential (MESP) analysis. The present study shows that the difference between MESP at the nucleus of the para carbon of substituted benzene and a carbon atom in benzene, designated as ΔVC, is very useful to quantify and classify substituent effects. On the basis of positive and negative ΔVC values, a broad classification of around 381 substituents into electron withdrawing and donating categories is made. Each category is again sorted based on the magnitude of ΔVC into subcategories such as very strong, strong, medium, and weak electron donating/withdrawing. Furthermore, the data are used to show the transferability and additivity of substituent effects in π-conjugated organic molecules such as condensed aromatic, olefinic, acetylenic, and heterocyclic systems. The transferability properties hold good for ΔVC in all these molecular systems. The additive properties of substituent effects are strongly reflected on ΔVC and the predictive power of the data to assign the total substituent effects of multi-substituted systems is verified. The ΔVC data and the present classification of substituents are very useful to design π-conjugated organic molecular systems with desired electron rich/poor character.

  16. Heterogeneous Chemistry of Carbonyls and Alcohols With Sulfuric Acid: Implications for Secondary Organic Aerosol Formation

    Science.gov (United States)

    Zhao, J.; Levitt, N.; Zhang, R.

    2006-12-01

    Recent environmental chamber studies have suggested that acid-catalyzed particle-phase reactions of organic carbonyls lead to multifold increases in secondary organic aerosol (SOA) mass and acid-catalyzed reactions between alcohols and aldehydes in the condensed phase lead to the formation of hemiacetals and acetals, also enhancing secondary organic aerosol growth. The kinetics and mechanism of the heterogeneous chemistry of carbonyls and alcohols with sulfuric acid, however, remain largely uncertain. In this talk, we present measurements of heterogeneous uptake of several carbonyls and alcohols on liquid H2SO4 in a wide range of acid concentrations and temperatures. The results indicate that uptake of larger carbonyls is explained by aldol condensation. For small dicarbonyls, heterogeneous reactions are shown to decrease with acidity and involve negligible formation of sulfate esters. Hydration and polymerization likely explain the measured uptake of such small dicarbonyls on H2SO4 and the measurements do not support an acid- catalyzed uptake. Atmospheric implications from our findings will be discussed.

  17. Content-related interactions and methods of reasoning within self-initiated organic chemistry study groups

    Science.gov (United States)

    Christian, Karen Jeanne

    2011-12-01

    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 content processing, and types of reasoning processes used by students within their groups. Our analysis showed that groups engaged in predominantly three types of interactions when discussing chemistry content: co-construction, teaching, and tutoring. Although each group engaged in each of these types of interactions at some point, their prevalence varied between groups and group members. Our analysis suggests that the types of interactions that were most common depended on the relative content knowledge of the group members as well as on the difficulty of the tasks in which they were engaged. Additionally, we were interested in characterizing the reasoning methods used by students within their study groups. We found that students used a combination of three content-relevant methods of reasoning: model-based reasoning, case-based reasoning, or rule-based reasoning, in conjunction with one chemically-irrelevant method of reasoning: symbol-based reasoning. The most common way for groups to reason was to use rules, whereas the least common way was for students to work from a model. In general, student reasoning correlated strongly to the subject matter to which students were paying attention, and was only weakly related to student interactions. Overall, results from this study may help instructors to construct appropriate tasks to guide what and how students study outside of the classroom. We found that students had a decidedly strategic approach in their study groups, relying heavily on material provided by their instructors, and using the reasoning strategies that resulted in the lowest levels of content processing. We suggest

  18. Research on Application to College Study in Organic Chemistry Teaching based on Computer Software

    OpenAIRE

    Wang Jing

    2016-01-01

    In order to give more accurate response to some basic chemical problems, it relates to the theoretical analysis and calculation so the computer chemistry has been developed rapidly. The computational chemistry software has its unique properties and it can achieve human-computer interaction showing vividness and intuitivenes setc. the effect is signifcant, which concrete teaching case analysis and in chemistry teaching by making good use of computer chemistry software so as to improve the actu...

  19. 医学有机化学绪论课的设计%Design for introductory class medical organic chemistry

    Institute of Scientific and Technical Information of China (English)

    李爽; 王海君

    2011-01-01

    Organic chemistry is a basic course in medical college. It is significant to leam organic chemistry. The introduction of organic chemistry is the first lesson to freshmen. It is important to them for the future study. Students understood the purpose of organic chemical by introduction "what is", "what to learn", "why to leam" "how to learn" through our explaining of introduction class. Develop their interest in learning organic chemistry.%有机化学是医学高等院校开设的一门基础课,学好有机化学是非常重要的.绪论课是教学中第一课,对学生今后的学习起着重要的作用.在绪论课的设计中,通过有机化学"是什么"、"学什么"、"为什么学"和"怎么学"这几个问题的讲解使学生明确学习目的,培养他们学习有机化学的兴趣.

  20. Research on Application to College Study in Organic Chemistry Teaching based on Computer Software

    Directory of Open Access Journals (Sweden)

    Wang Jing

    2016-01-01

    Full Text Available In order to give more accurate response to some basic chemical problems, it relates to the theoretical analysis and calculation so the computer chemistry has been developed rapidly. The computational chemistry software has its unique properties and it can achieve human-computer interaction showing vividness and intuitivenes setc. the effect is signifcant, which concrete teaching case analysis and in chemistry teaching by making good use of computer chemistry software so as to improve the actual effect of classroom teaching enrich the teaching contents in class animate the classroom atmosphere and enhance students enthusiasm of learning chemistry.

  1. Investigations of Global Chemistry-Climate Interactions and Organic Aerosol Using Atmospheric Modeling

    Science.gov (United States)

    Pye, Havala Olson Taylor

    Aerosol, or particulate matter (PM), is an important component of the atmosphere responsible for negative health impacts, environmental degradation, reductions in visibility, and climate change. In this work, the global chemical transport model, GEOS-Chem, is used as a tool to examine chemistry-climate interactions and organic aerosols. GEOS-Chem is used to simulate present-day (year 2000) and future (year 2050) sulfate, nitrate, and ammonium aerosols and investigate the potential effects of changes in climate and emissions on global budgets and U.S. air quality. Changes in a number of meteorological parameters, such as temperature and precipitation, are potentially important for aerosols and could lead to increases or decreases in PM concentrations. Although projected changes in sulfate and nitrate precursor emissions favor lower PM concentrations over the U.S., projected increases in ammonia emissions could result in higher nitrate concentrations. The organic aerosol simulation in GEOS-Chem is updated to include aerosol from primary semivolatile organic compounds (SVOCS), intermediate volatility compounds (IVOCs), NOx dependent terpene aerosol, and aerosol from isoprene + NO3 reaction. SVOCs are identified as the largest global source of organic aerosol even though their atmospheric transformation is highly uncertain and emissions are probably underestimated. As a result of significant nighttime terpene emissions, fast reaction of monoterpenes with the nitrate radical, and high aerosol yields from NO3 oxidation, biogenic hydrocarbons reacting with the nitrate radical are expected to be a major contributor to surface level aerosol concentrations in anthropogenically influenced areas such as the United States. Globally, 69 to 88 Tg/yr of aerosol is predicted to be produced annually, approximately 22 to 24 Tg/yr of which is from biogenic hydrocarbons.

  2. Organic geochemistry and pore water chemistry of sediments from Mangrove Lake, Bermuda

    Science.gov (United States)

    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. Water chemistry in Kuji river. Its spatial and seasonal variations in major ions and organic substances

    Energy Technology Data Exchange (ETDEWEB)

    Niina, Toshiaki; Matsunaga, Takeshi; Amano, Hikaru [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1996-02-01

    As a basic research with a aim to clarify the migration behavior of radionuclides in rivers, the characteristics of dissolved ions and organic substances in river water, which characteristics may affect the behavior, was investigated. The investigation was carried out for the Kuji river in the northern Kanto district (Japan) comprising four sampling campaigns in 1994 for 10 locations from the upstream to the downstream. Concentrations of major ions, iron and manganese species and organic substances were analyzed in laboratory. Values of temperature of the water, pH, conductivity, dissolved oxygen were measured in the field. This investigation was conducted mainly under low water flow conditions of the river, while a limited number of campaigns were under high flow conditions due to precipitation events. The concentrations of major inorganic ions increased steadily toward the down-stream, resulting in approximately two times increase for the traveling distance of 100 km. They showed a seasonal variation that they were highest in the spring and lowest in the autumn when there were most concentrated precipitation events in a year. The constituents were mainly Na{sup +}, Ca{sup 2+}, SO{sub 4}{sup 2-} and HCO{sub 3}{sup -}, and were similar for every sampling locations and seasons. Concentrations of dissolved organic substances (carbon compounds) were lowest in the upstream and increased about twice in the downstream as well as major inorganic ions. Their level was 1-3 mg/l, which can be ranked as relatively lower in general values for fresh water environments. They were highest in the spring (average over the locations: 2.2 mg/l) and lowest in the autumn (1.3 mg/l) and also in the winter (1.3 mg/l). These results will be useful as a basic understanding of spatial and seasonal variations of river water chemistry, especially related to the organic substances which can bind with radionuclides to make a mobile complex. (author).

  4. Ivermectin treatment of bovine psoroptic mange: effects on serum chemistry, hematology, organ weights, and leather quality.

    Science.gov (United States)

    Rehbein, S; Visser, M; Meyer, M; Lindner, T

    2016-04-01

    Psoroptic mange is a skin disease which may result in serious health and welfare problems and important economic losses. Apart from the effect on weight gain, little information is available concerning other responses of the organism consequent to the successful therapy of bovine psoroptic mange. Accordingly, serum chemistry, hematology, organ weights, and leather quality of young bulls with experimentally induced clinical Psoroptes ovis mange and treated with either ivermectin long-acting injection (IVM LAI; IVOMEC(®) GOLD, Merial) or saline (n = 16 each) were examined 8 weeks after treatment when all IVM LAI-treated bulls were free of live P. ovis mites while the saline-treated bulls maintained clinical mange. IVM LAI-treated bulls had higher (p leathers produced from the IVM LAI-treated bulls showed significantly (p leathers from the saline-treated bulls, and significantly (p leather from the IVM LAI-treated bulls was of usable quality than the size of leather from the saline-treated bulls. Overall, these findings provided evidence that many changes, which are indicative of impaired protein and energy metabolism, immune system function, and performance resultant from clinical psoroptic mange, improved substantially within 8 weeks of successful treatment with injectable ivermectin.

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

    Science.gov (United States)

    Petraglia, Riccardo; Nicolaï, Adrien; Wodrich, Matthew D; Ceriotti, Michele; Corminboeuf, Clemence

    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.

  6. Two Methods of Determining Total Phenolic Content of Foods and Juices in a General, Organic, and Biological (GOB) Chemistry Lab

    Science.gov (United States)

    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…

  7. The Cyclohexanol Cycle and Synthesis of Nylon 6,6: Green Chemistry in the Undergraduate Organic Laboratory

    Science.gov (United States)

    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. Bringing Research into a First Semester Organic Chemistry Laboratory with the Multistep Synthesis of Carbohydrate-Based HIV Inhibitor Mimics

    Science.gov (United States)

    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…

  9. Tetraglyme Trap for the Determination of Volatile Organic Compounds in Urban Air: Projects for Undergraduate Analytical Chemistry

    Science.gov (United States)

    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…

  10. The Effect of Systemic Synthesis Questions [SSynQs] on Students' Performance and Meaningful Learning in Secondary Organic Chemistry Teaching

    Science.gov (United States)

    Hrin, Tamara N.; Milenkovic, Dušica D.; Segedinac, Mirjana D.

    2016-01-01

    Many studies in the field of chemical education have emphasized the fact that students at secondary level have considerable difficulties in mastering organic chemistry contents. As a result, they choose to learn these contents in a "rote" way. Taking this fact into consideration, the first aim of our study was to help students in…

  11. Development and Assessment of a Diagnostic Tool to Identify Organic Chemistry Students' Alternative Conceptions Related to Acid Strength

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  14. Soil organic matter chemistry in allophanic soils: a pyrolysis-GC/MS study of a Costa Rican Andosol catena

    NARCIS (Netherlands)

    Buurman, P.; Peterse, F.; Almendros Martin, G.

    2007-01-01

    Soil organic matter (SOM) in allophanic soils is supposed to accumulate due to protection caused by binding to allophane, aluminium and iron. We investigated a catena of allophanic and non-allophanic soils in Costa Rica to determine the effect of such binding mechanisms on SOM chemistry. These soils

  15. The Use of Modular Computer-Based Lessons in a Modification of the Classical Introductory Course in Organic Chemistry.

    Science.gov (United States)

    Stotter, Philip L.; Culp, George H.

    An experimental course in organic chemistry utilized computer-assisted instructional (CAI) techniques. The CAI lessons provided tutorial drill and practice and simulated experiments and reactions. The Conversational Language for Instruction and Computing was used, along with a CDC 6400-6600 system; students scheduled and completed the lessons at…

  16. Self-Regulated Learning Study Strategies and Academic Performance in Undergraduate Organic Chemistry: An Investigation Examining Ethnically Diverse Students

    Science.gov (United States)

    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…

  17. ConfChem Conference on Flipped Classroom: Improving Student Engagement in Organic Chemistry Using the Inverted Classroom Model

    Science.gov (United States)

    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…

  18. Extraction and [superscript 1]H NMR Analysis of Fats from Convenience Foods: A Laboratory Experiment for Organic Chemistry

    Science.gov (United States)

    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…

  19. Reaction Mechanisms for the Limited Reversibility of Li-O2 Chemistry in Organic Carbonate Electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Wu; Xu, Kang; Viswanathan, Vilayanur V.; Towne, Silas A.; Hardy, John S.; Xiao, Jie; Nie, Zimin; Hu, Dehong; Wang, Deyu; Zhang, Jiguang

    2011-11-15

    The Li-O2 chemistry in nonaqueous carbonate electrolytes and the underneath reason of its limited reversibility was exhaustively investigated. The discharge products collected from the air cathode in a Li-O2 battery at different depth of discharge (DOD) were systematically analyzed with X-ray diffraction. It is revealed that, independent of the discharge depth, lithium alkylcarbonate (either lithium propylenedicarbonate - LPDC, or lithium ethylenedicarbonate - LEDC, with other related derivatives) and lithium carbonate (Li2CO3) are always the main products, obviously originated from the electrolyte solvents propylene carbonate (PC) and ethylene carbonate (EC). These lithium alkylcarbonates are obviously generated from the single-electron reductive decomposition of the corresponding carbonate solvents initiated by the attack of superoxide radical anions. On the other hand, neither lithium peroxide (Li2O2) nor lithium oxide (Li2O) is detected. More significantly, from in situ gas chromatography/mass spectroscopy it is found that Li2CO3 and Li2O cannot be oxidized even when charged up to 4.6 V vs. Li/Li+, while LPDC, LEDC and Li2O2 are readily able to, with CO2 and CO released with the re-oxidation of LPDC and LEDC. It is therefore concluded that the quasi-reversibility of Li-O2 chemistry observed hitherto in an organic carbonate-based electrolyte is actually reliant on the formation of lithium alkylcarbonates through the reductive decomposition of carbonate solvents during discharge process and the subsequent oxidation of these same alkylcarbonates during charge process. It is the poor oxidizability of these alkylcarbonate species that constitutes the obstruction to an ideal rechargeable Li-O2 battery.

  20. Designing Undergraduate-Level Organic Chemistry Instructional Problems: Seven Ideas from a Problem-Solving Study of Practicing Synthetic Organic Chemists

    Science.gov (United States)

    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…

  1. Improving Students' Understanding of Molecular Structure through Broad-Based Use of Computer Models in the Undergraduate Organic Chemistry Lecture

    Science.gov (United States)

    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…

  2. Determination of concentration of radon, volatile organic compounds (VOC) and water chemistry in springs near to Popocatepetl volcano

    International Nuclear Information System (INIS)

    Popocatepetl volcano is a high-risk active volcano in Central Mexico where the highest population density in the country is settled. Radon in the soil and groundwater together with water chemistry from samples of nearby springs is analysed as a function of the 2002-2003 volcanic activity. Soil radon indicated fluctuations related both the meteorological parameters and sporadic explosive events. Groundwater radon showed essentially differences in concentration due to the specific characteristics of the studied springs. Water chemistry showed stability along the monitoring period indicating also differences between springs. No anthropogenic pollution from volatile organic compounds was observed. (Author)

  3. Design of Organic Transformations at Ambient Conditions: Our Sincere Efforts to the Cause of Green Chemistry Practice.

    Science.gov (United States)

    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.

  4. Design of Organic Transformations at Ambient Conditions: Our Sincere Efforts to the Cause of Green Chemistry Practice.

    Science.gov (United States)

    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. PMID:26572548

  5. A cognitive model of second-year organic chemistry students' conceptualizations of mental molecular rotation

    Science.gov (United States)

    Briggs, Michael W.

    The goal of this research was to answer the question, "What is a plausible explanation (model) of the cognitive structure and processes that facilitate mental molecular rotation?". This work used phenomenographic methodology and techniques of interview and think-aloud protocol. Constructivism was the theoretical framework. At the outset of the research, I designed nine tasks to obtain participant articulations of conceptualizations of mental molecular rotations. Articulations from five second-year organic chemistry students attending a Midwestern research university became the research data. Analysis produced four emerging themes along two axes: visualization representation and modeling cognition. These two axes formed a mental space, which was modeled by structure and processes that facilitated mental molecular rotation. A theoretical cognitive model of mental molecular rotation was based on the work of two researchers: Robbie Case and Richard Lesh. Lesh's "mental model" is composed of cognitive elements and operations, which are distributed over heeded local and global cognitive sub-models whereas Case deals with unheeded central conceptual structures. The models and structures interact to produce new knowledge and facilitate the use of existing knowledge. Two predictions of the theory of mental molecular rotation were elaborated. Students without a set of operations in a central conceptual structure will not be able to mentally rotate molecules. This is true even if a set of components, other than "operation", is constructed. The artifacts of mental molecular rotation can be used to determine the state of construction of the central conceptual structure responsible for mental molecular rotation.

  6. Organic peroxyl radical photolysis in the near-infrared: Effects on tropospheric chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Frost, G.J.; Ellison, G.B.; Vaida, V.

    1999-12-09

    This work is an investigation of the effects of near-infrared photolysis of organic peroxyl radicals (RO{sub 2}) on tropospheric chemistry. The authors propose that the excitation of an RO{sub 2} to its lowest excited electronic state with near-infrared (near-IR) light is followed by intramolecular reactions that produce hydroxyl (OH) or hydroperoxyl (HO{sub 2}) radicals. Spectra to this low-lying state have recently been obtained, but absorption cross sections for this electronic transition and yields of the resulting photoproducts have not been directly measured. The authors suggest a limiting range of cross sections from estimates for the same transition in HO{sub 2} and by comparison to other allowed electronic transitions. On the basis of a thermochemical assessment, OH and an aldehyde are proposed as the principal photoproducts of near-IR photolysis of RO{sub 2}. These photolysis reactions are included in a model of the troposphere with a standard photochemical mechanism and conditions appropriate to remote, rural, and urban locations. Inclusion of RO{sub 2} photolysis has a small effect on any of the major tropospheric chemical constituents if lower limit estimates of the absorption cross sections are used. Midrange or upper limit cross section estimates result in significant departures from the currently accepted photochemical scheme. These studies provide a clear need for further measurements of RO{sup 2} absorption cross sections and photoproduct yields, which are the principal uncertainties.

  7. Extending physical chemistry to populations of living organisms. First step: measuring coupling strength

    CERN Document Server

    Di, Zengru

    2013-01-01

    For any system, whether physical or non-physical, knowledge of the form and strength of inter-individual interactions is a key-information. In an approach based on statistical physics one needs to know the interaction Hamiltonian. For non-physical systems, based on qualitative arguments similar to those used in physical chemistry, interaction strength gives useful clues about the macroscopic properties of the system. Even though our ultimate objective is the understanding of social phenomena, we found that systems composed of insects (or other living organisms) are of great convenience for investigating group effects. In this paper we show how to design experiments that enable us to estimate the strength of interaction in groups of insects. By repeating the same experiments with increasing numbers of insects, ranging from less than 10 to several hundreds, one is able to explore key-properties of the interaction. The data turn out to be consistent with a global correlation that is independent of distance (at l...

  8. Evaluation of NO+ reagent ion chemistry for online measurements of atmospheric volatile organic compounds

    Science.gov (United States)

    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.

  9. Adsorption and desorption of dissolved organic matter by carbon nanotubes: Effects of solution chemistry.

    Science.gov (United States)

    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.

  10. The meteoritic record of presolar and early solar system organic chemistry. [Abstract only

    Science.gov (United States)

    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.

  11. BIO-ORGANIC CHEMISTRY QUARTERLY REPORT. March through05/1963

    Energy Technology Data Exchange (ETDEWEB)

    Various

    1963-07-23

    This report covers the following titles: (1) Fertility and litter size of normally ovulated and artificially ovulated mice; (2) Further studies on sterility produced in male mice by deuterium oxide; (3) Planarian disaggregation; (4) Uptake of organic compounds by planarians. II; (5) Effects of environmental complexity and training on acetylcholinesterase and cholinesterase activity in rat brain; (6) Effects of environmental complexity and training on brain chemistry and anatomy among mature rats; (7) Improvements in paper chromatographic techniques for labeled cell extracts; (8) measurement and adjustment of pH in small volumes of solutions; (9) Carbon-14 and Nitrogen-15 tracer studies of amino acid synthesis during photosynthesis by Chlorella Pyrenoidosa; (10) Photosynthesis of {sup 14}C-labeled protein from {sup 14}CO{sub 2} by Chlorella; (11) Further studies on carboxydismutase; (12) Electron microscopy of chlorophyll a crystals; (13) The possible role of chromanyl phosphates in oxidative and photosynthetic phosphorylation; (14) Oxidation-reductions of some coenzymes; (15) Preparation of some [{sup 14}C] labeled substances: glucose-6-phosphate, fructose-6-phosphate, 6-phosphogluconic acid, pyruvic acid, and succinic acid; (16) attempt to synthesize high molecular weight polynucleotides using Schramm's purely chemical method; and (17) Optical properties of some dye-polyanion complexes.

  12. Creating a Discovery Platform for Confined-Space Chemistry and Materials: Metal-Organic Frameworks.

    Energy Technology Data Exchange (ETDEWEB)

    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

  13. Small-molecule azomethines: organic photovoltaics via Schiff base condensation chemistry

    NARCIS (Netherlands)

    Petrus,M. L.; Bouwer, R. K. M.; Lafont, U.; Athanasopoulos, S.; Greenham, N. C.; Dingemans, T. J.

    2014-01-01

    Conjugated small-molecule azomethines for photovoltaic applications were prepared via Schiff base condensation chemistry. Bulk heterojunction (BHJ) devices exhibit efficiencies of 1.2% with MoOx as the hole-transporting layer. The versatility and simplicity of the chemistry is illustrated by prepari

  14. Combining coordination and supramolecular chemistry for the formation of uranyl-organic hybrid materials

    Energy Technology Data Exchange (ETDEWEB)

    Deifel, N. P.; Cahill, Christopher L.

    2011-01-01

    Three hybrid compounds have been synthesized through hydrothermal reactions of UO{sub 2}(NO{sub 3}){sub 2}·6H{sub 2}O with 4-halobenzoic acid (X = Cl, Br, I). The formation of these compounds utilizes a composite synthesis methodology that explicitly employs aspects of both coordination chemistry and supramolecular chemistry (namely halogen---halogen interactions).

  15. Illustrating Concepts in Physical Organic Chemistry with 3D Printed Orbitals

    Science.gov (United States)

    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…

  16. The Application of Fuzzy-ANP and SD Software in the Assessment of Organic Chemistry Teachers' Bilingual Teaching Competency

    Directory of Open Access Journals (Sweden)

    Yijun Zhang

    2013-06-01

    Full Text Available The assessment of organic chemistry teachers' bilingual teaching competency plays a crucial role in improving their teaching quality. In this study, 13 indices in five aspects: teaching quality, teaching content, teaching organization, teaching methods, and teaching effects, have been identified as impact indices for assessing the bilingual teaching competency of organic chemistry teachers. Meanwhile, the ANP (Analytic Network Process model is set up, and the Super Decisions software is used to compute the comprehensive weight of the 13 impact factors. A five-degree fuzzy comment set including very satisfied, satisfied, mediocre, dissatisfied, and very dissatisfied is established. The five-degree evaluation data on the 13 impact indices are collected through questionnaires distributed to students. Index weights and evaluation data are synthesized to obtain the final assessment results of organic chemistry teachers' bilingual teaching competency. The Fuzzy-ANP model has taken the internal relations and external dependency of 13 indices into consideration, which makes the assessment results more authentic and reliable. Therefore, this model is worthy of a more extensive application.

  17. 师范院校《有机化学》教学中化学史的渗透%Integration of Chemistry History into Organic Chemistry Teaching in Normal College

    Institute of Scientific and Technical Information of China (English)

    王毓

    2015-01-01

    Organic Chemistry is an important basic course for normal college students, and it also has the important function in normal chemistry teaching.According to the characteristic, the integration of chemistry history into organic chemistry can not only stimulate up students'learning interest, broaden students'knowledge, help to deepen the understanding and mastery of theorectical knowledge, but also cultivate students'science literacy and abilities in the teaching process of organic chemistry.It is important that chemistry history is integrated into Organic Chemistry in the teaching process.%有机化学是师范院校化学专业的一门重要基础课,在师范院校化学专业教学中具有重要的地位。针对有机化学学科的特点,在机化学课堂教学中,通过引入与课程内容相关的化学史,不仅可以激发学生的学习兴趣,拓宽知识面,加深学生对所学理论知识的理解与掌握,而且有助于培养学生的科学素养和综合素质。化学史在有机化学课堂教学中的作用是不可忽视的。

  18. Exploring Atmospheric Aqueous Chemistry (and Secondary Organic Aerosol Formation) through OH Radical Oxidation Experiments, Droplet Evaporation and Chemical Modeling

    Science.gov (United States)

    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

  19. Organic Iodine(I, III, and V) Chemistry: 10 Years of Development at the Medical University of Warsaw, Poland

    OpenAIRE

    Lech Skulski

    2000-01-01

    This review reports some novel (or considerably improved) methods for the synthesis of aromatic iodides, (dichloroiodo)arenes, (diacetoxyiodo)arenes, iodylarenes and diaryliodonium salts, as well as some facile, oxidative anion metatheses in crude diaryliodonium halides and, for comparison, potassium halides. All these new results were obtained in our laboratory over the past decade (1990-2000). A full list of our papers dealing with the organic iodine(I, III and V) chemistry, covering exlusi...

  20. Organic Iodine(I, III, and V Chemistry: 10 Years of Development at the Medical University of Warsaw, Poland

    Directory of Open Access Journals (Sweden)

    Lech Skulski

    2000-12-01

    Full Text Available This review reports some novel (or considerably improved methods for the synthesis of aromatic iodides, (dichloroiodoarenes, (diacetoxyiodoarenes, iodylarenes and diaryliodonium salts, as well as some facile, oxidative anion metatheses in crude diaryliodonium halides and, for comparison, potassium halides. All these new results were obtained in our laboratory over the past decade (1990-2000. A full list of our papers dealing with the organic iodine(I, III and V chemistry, covering exlusively the aromatic derivatives, is also provided.

  1. Modulating the rate of charge transport in a metal-organic framework thin film using host:guest chemistry.

    Science.gov (United States)

    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.

  2. Modulating the rate of charge transport in a metal-organic framework thin film using host:guest chemistry.

    Science.gov (United States)

    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. PMID:26666952

  3. Role of aldehyde chemistry and NOx concentrations in secondary organic aerosol formation

    Directory of Open Access Journals (Sweden)

    P. O. Wennberg

    2010-04-01

    Full Text Available 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(OOONO2 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.

  4. Role of aldehyde chemistry and NOx concentrations in secondary organic aerosol formation

    Directory of Open Access Journals (Sweden)

    P. O. Wennberg

    2010-08-01

    Full Text Available 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(OOONO2 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.

  5. Sterilization affects soil organic matter chemistry and bioaccumulation of spiked p,p'-DDE and anthracene by earthworms

    Energy Technology Data Exchange (ETDEWEB)

    Kelsey, Jason W., E-mail: kelsey@muhlenberg.ed [Program in Environmental Science and Department of Chemistry, Muhlenberg College, 2400 Chew Street, Allentown, PA 18104 (United States); Slizovskiy, Ilya B.; Peters, Richard D.; Melnick, Adam M. [Program in Environmental Science and Department of Chemistry, Muhlenberg College, 2400 Chew Street, Allentown, PA 18104 (United States)

    2010-06-15

    Laboratory experiments were conducted to assess the effects of soil sterilization on the bioavailability of spiked p,p'-DDE and anthracene to the earthworms Eisenia fetida and Lumbricus terrestris. Physical and chemical changes to soil organic matter (SOM) induced by sterilization were also studied. Uptake of both compounds added after soil was autoclaved or gamma irradiated increased for E. fetida. Sterilization had no effect on bioaccumulation of p,p'-DDE by L. terrestris, and anthracene uptake increased only in gamma-irradiated soils. Analyses by FT-IR and DSC indicate sterilization alters SOM chemistry and may reduce pollutant sorption. Chemical changes to SOM were tentatively linked to changes in bioaccumulation, although the effects were compound and species specific. Artifacts produced by sterilization could lead to inaccurate risk assessments of contaminated sites if assumptions derived from studies carried out in sterilized soil are used. Ultimately, knowledge of SOM chemistry could aid predictions of bioaccumulation of organic pollutants. - Soil sterilization affects soil organic matter chemistry and pollutant bioaccumulation.

  6. Organization of a cognitive activity of students when teaching analytical chemistry

    OpenAIRE

    А. Tapalova; O. Suleimenova

    2012-01-01

    Qualitative analysis allows using basic knowledge of general and inorganic chemistry for the solution of practical problems, disclosure the chemism of the processes that are fundamental for  the methods of analysis. Systematic qualitative analysis develops analytical thinking, establishes a scientific style of thinking of students.Сhemical analysis requires certain skills and abilities and develops the general chemical culture of the future teachers оn chemistry. The result can be evaluated i...

  7. A química orgânica na consolidação dos conceitos de átomo e molécula Organic chemistry in the consolidation of the concepts of atom and molecule

    OpenAIRE

    Tânia de Oliveira Camel; Carlos B. G. Koehler; Carlos A. L. Filgueiras

    2009-01-01

    The present work discusses the appearance of the concepts of valence and molecular structure, and describes the appropriation and evolution of the concept of molecule in the period following the publication of Avogadro's Hypothesis. The point of reference is the development of what became known as Organic Chemistry, which encompassed Pharmacy, Physiological Chemistry, Animal and Plant Chemistry, Chemistry of Dyestuffs, Agricultural Chemistry, and the fledgling Organic Synthesis industry in th...

  8. Aerobic Alcohol Oxidation Using a Copper(I)/TEMPO Catalyst System: A Green, Catalytic Oxidation Reaction for the Undergraduate Organic Chemistry Laboratory

    Science.gov (United States)

    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…

  9. Substantial secondary organic aerosol formation in a coniferous forest: observations of both day and night time chemistry

    Directory of Open Access Journals (Sweden)

    A. K. Y. Lee

    2015-10-01

    Full Text Available 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.

  10. A linguagem química e o ensino da química orgânica Chemical language and organic chemistry chemistry teaching

    Directory of Open Access Journals (Sweden)

    Nídia Franca Roque

    2008-01-01

    Full Text Available The importance of chemical language and specifically of molecular models and their representations in the development of chemistry is discussed. Structural formulas are projections of molecular models used as a specific language by chemists. The meaningful learning of chemistry requires knowledge of this language. The use of these analogical symbols without the necessary understanding engenders difficulties for the learning of chemistry.

  11. The effects of organic matter-mineral interactions and organic matter chemistry on diuron sorption across a diverse range of soils.

    Science.gov (United States)

    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.

  12. 绿色化学与微型有机化学实验研究与实践分析%Research and Practice Analysis of Green Chemistry and Micro-organic Chemistry Experiment

    Institute of Scientific and Technical Information of China (English)

    商桂君

    2014-01-01

    This paper will starts from establishing the people's green awareness to analyzes micro-organic chemistry experiment, and proposes using the concept of green chemistry to reform the organic chemistry experiment teaching, expects to better know the chemistry experiment teaching.%本文将从树立人们的绿色化意识出发,对微型有机化学实验进行深入分析,并提出利用绿色化学的理念对有机化学实验教学进行改革具体措施,以期更好的知道化学实验教学。

  13. How Science/Technology/Society relations are approached in the contents of organic functions in high school chemistry

    Directory of Open Access Journals (Sweden)

    Carmem Lúcia Costa Amaral

    2009-03-01

    Full Text Available This paper aimed to verify how the relation between Science/Technology/Society (STS is present in Chemistry textbooks recommended by the Brazilian Ministry of Education. The interest in textbooks is due to the fact that they constitute important resources used by teachers to prepare their classes. Thus, researches in this area are necessary to indicate how the authors could improve the quality of their books. We believe that one way to do this is the introduction of the STS relation, which took place because of the necessity in establishing new ways of teaching, specially the teaching of science. One of the goals of STS education is to create conditions to develop abilities and competences that qualify the students for discussions concerning scientific and technologic questions of everyday life. The analysis of testbooks used the descriptors and indicators developed by Fracalanza and Megid-Neto (2006 as reference. In order to carry out the study, we chose the area of Organic Chemistry, more specifically contents referring to organic functions, with great use in society. In general, the results showed that STS relations are not totally observed in the investigated contents, contributing to the development of Chemistry classes through activities apart from the students social context.

  14. Annual report 1984 Chemistry Department

    International Nuclear Information System (INIS)

    This report contains a brief survey of the main activities in the Chemistry Department. All articles and reports published and lectures given in 1984 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry , environmental chemistry, polymer chemistry, geochemistry and waste disposal, radical chemistry, positron annihilation, mineral processing, and general. (author)

  15. Inspiration Was Just Floating in the Natural Air-Research in Key Laboratory of Organic Solids, Institute of Chemistry of CAS

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Sponsored by NSFC,CAS,and Ministry of Science and Technology,the Key Lab of Organic Solids in Institute of Chemistry of CAS developed tungsten oxide "light switch" membrane,which has wetting and discolorment abilities.

  16. BIO-ORGANIC CHEMISTRY QUARTERLY REPORT. December 1961, January and February 1962

    Energy Technology Data Exchange (ETDEWEB)

    Various,

    1962-04-03

    Progress is reported in investigations on the polymerization of formaldehyde, ultraviolet irradiation of aqueous HC/sup 14/N, radiation chemistry of nucleic acid constituents, oxidation of free sugars and aldonic acid derivatives by Acetobacter suboxydans, preparation and isolation of C/sup 14/O/ sub 2/~ enzyme, metabolism of C/sup 14/-ribulose diphosphate by Nitrobacter agilis, C/sup 14/O/sub 2/ metabolism of Hordeum valgare seedlings during the development of the photosynthetic apparatus, location and chemical characterization of RNA in the chloroplasts of Spinacea oleracea, inhibition of dark bleaching by stroma extracts and by inert gases, ESR studies on chromatophores from Rhodospirillium rubrum and on quantasomes from spinach chloroplasts, and phthalocyanine manganese and etioporphyrin manganese complexes. (J.R.D.) It has been known for a hundred years that formaldehyde polymerizes to carbohydrate substances in alkaline media. Although the reaction has long attracted much attention, only recently has a detailed qualitative analysis of the products been carried out by chromatographic methods. We have started to re-examine this reaction by combining chromatography with radioactive tracer techniques in the hope of refining the quantitative aspects of the analysis. Our particular interest has been to develop methods for determining the relative proportions of ribose and ribulose in the mixtures of sugars formed in basic media, as well as under other polymerizing conditions. The finding of large amounts of these sugars might help to explain the occurrence of ribose as the only basic sugar in the fundamental replicating molecules--the nucleic acids. Formaldehyde is thought to have been present in the primitive reducing atmosphere which existed before life first appeared. The ribonucleic acids must have appeared in the constitution of reproducing systems at a very early stage in the development of living organisms. In this study, the polymerizations of formaldehyde

  17. [JSPS Asian core program on cutting-edge organic chemistry in Asia].

    Science.gov (United States)

    Isobe, Minoru; Nishikawa, Toshio

    2009-04-01

    The vision to establish this program was to establish and extend cooperative research efforts beyond the intraregional boundaries. The Japan Society for the Promotion of Science (JSPS) has taken an initiative to support an Asian Core Program, which aims to create world-class research hubs within the Asian region and foster the development of the next generation of leading researchers by establishing sustainable collaborative relations among research and educational institutions in Asian countries. Nagoya University strongly supports and is the Core University of this program with Minoru Isobe and Toshio Nishikawa serving as the coordinator. Representing their respective countries/regions, Guo-Qiang Lin and Zhu-Jun Yao (China, Shanghai), Sunggak Kim and Kwan-Soo Kim (Korea), Somsak Ruchirawat (Thailand), and Chun-Chen Liao and Biing-Jiun Uang (China, Taipei) share in the vision to enhance collaborative efforts. As coordinators they have invited many cooperative universities/institutes in their home countries/regions to start the network since 2005. Singapore (Tech-Peng Loh) has joined lately, and Hong Kong is represented by Henry Wong. All cooperating regions also agreed to support this program by acquiring matching funds for the duration of the program, that is, until March 2010. This program is jointly supported by the JSPS (Japan), the NNSFC (China, Beijing), the NSCT (China, Taipei), the KOSEF/CMDS (Korea), the NRCT/CRI (Thailand), and the IUPAC for an East Asian Network Task group project. Pauline Chiu takes the general secretary work. The initiation of the Asian Core Program and the Inauguration Conference (The 0th International Conference on Cutting-Edge Organic Chemistry in Asia; ICCEOCA-0) was held in Nagoya (2006. 3), which was followed by ICCEOCA-1 in Okinawa, Japan (2006. 10), ICCEOCA-2 in Busan, Korea (2007. 9), ICCEOCA-3 in Hangzhou, China (2008. 10). A post symposium of ICCEOCA-1 was held in Hsinchu, Taiwan (2006. 10), and a satellite symposium of

  18. Volatile organic compounds in the New England troposphere: Atmospheric chemistry and measurement techniques

    Science.gov (United States)

    Ambrose, Jesse L.

    Atmospheric measurements made at Appledore Island, Maine were used to investigate nighttime nitrate radical (NO3) chemistry and its significance for the nitrogen oxides (NOx = NO + NO2) budget in the Gulf of Maine region during the summer of 2004 International Consortium for Atmospheric Research on Transport and Transformation field campaign. Removal of NOx was strongly dependent on reactions of NO3 with biogenic volatile organic compounds and the fate of dinitrogen pentoxide (N 2O5). For three case studies, temporal profiles of NO 3 were calculated from measured parameters. Comparisons between measured and calculated NO3 mixing ratios highlighted significant uncertainties in the kinetic parameters governing gas-phase and heterogeneous N2O 5 hydrolysis. Removal of NOx was estimated to be ˜11 ppbv day-1, with nighttime chemical pathways contributing ˜50%. Atmospheric measurements made at the AIRMAP atmospheric monitoring station Thompson Farm (THF) during summer, 2004 were used to test the specificity of a proton transfer reaction-mass spectrometer (PTA-MS) for atmospheric toluene measurements under conditions often dominated by biogenic emissions. Quantitative estimates were made of potential interferences in the PTR-MS toluene measurements related to sampling and analysis of monoterpenes, including fragmentation of the monoterpenes and some of their primary carbonyl oxidation products in the PTR-MS drift tube. The analysis supported only minor interferences from the investigated fragmentation sources, suggesting that toluene can be reliably quantified by PTR-MS with the operating parameters used, under the ambient compositions probed. This work extends the range of field conditions under which PTR-MS validation studies have been conducted. A GC instrument was developed for measurement of hydrogen cyanide (HCN) in the lower atmosphere. Its major features include a cold temperature analyte enrichment system, a robust porous polymer stationary phase capillary

  19. Organization of a cognitive activity of students when teaching analytical chemistry

    Directory of Open Access Journals (Sweden)

    А. Tapalova

    2012-12-01

    Full Text Available Qualitative analysis allows using basic knowledge of general and inorganic chemistry for the solution of practical problems, disclosure the chemism of the processes that are fundamental for  the methods of analysis. Systematic qualitative analysis develops analytical thinking, establishes a scientific style of thinking of students.Сhemical analysis requires certain skills and abilities and develops the general chemical culture of the future teachers оn chemistry. The result can be evaluated in the course of self-control, peer review, and solving creative problems. Mastering the techniques of critical thinking (comparison, abstraction, generalization and their use in a particular chemical material - are necessary element in the formation of professional thinking of the future chemistry teacher.

  20. Bringing the science of proteins into the realm of organic chemistry: total chemical synthesis of SEP (synthetic erythropoiesis protein).

    Science.gov (United States)

    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.

  1. Correlations of organic chemistry study of the 2nd year “Pharmacy” faculty students of specialty “Technology of perfume-cosmetic preparations”

    OpenAIRE

    Antypenko, L. M.; Kandybey, K. I.; Kovalenko, S. I.

    2015-01-01

    In order to analyze the organic chemistry study for 2nd year students of specialty “Technology of perfume-cosmetic preparations” in Zaporizhzhya State Medical University, correlations between preparation time for the theoretical part of the classes, for computer testing and its percentage, the impact of the organic chemistry at school to university mark, and in general for all disciplines attestation, using Pearson and Spearman correlations, Kolmogorov-Smirn...

  2. Filtrates and Residues: Saturated and Unsaturated Fats: An Organic Chemistry Demonstration.

    Science.gov (United States)

    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.…

  3. Green, Enzymatic Syntheses of Divanillin and Diapocynin for the Organic, Biochemistry, or Advanced General Chemistry Laboratory

    Science.gov (United States)

    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…

  4. Sustaining Change in Upper Level Courses: Peer-Led Workshops in Organic Chemistry and Biochemistry

    Science.gov (United States)

    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…

  5. Thiophene 1,1-dioxides as unique building blocks in modern organic synthesis and materials chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Moiseev, Andrew M; Balenkova, Elizabeth S; Nenajdenko, Valentine G [Department of Chemistry, M.V. Lomonosov Moscow State University, Moscow (Russian Federation)

    2006-12-31

    Data on the synthesis, reactivity features and the key chemical transformations of thiophene 1,1-dioxides are summarised and described systematically. The attention is focused on recent achievements in the chemistry of thiophene dioxides concerning both their practical use and theoretical studies.

  6. Some aspects of the organic, biological and inorganic chemistry of astatine

    International Nuclear Information System (INIS)

    Astatine has no stable isotopes and the radioactive isotopes with half-lives sufficiently long for chemical experiments (209At, 210At, 211At) must be produced artificially with a cyclotron or with a high energy accelerator by spallation of Th. This thesis deals with the synthesis and chemistry of At-compounds and the determination of some of their properties. (C.F.)

  7. Organic Chemistry YouTube Writing Assignment for Large Lecture Classes

    Science.gov (United States)

    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…

  8. Factors Contributing to Problem-Solving Performance in First-Semester Organic Chemistry

    Science.gov (United States)

    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…

  9. Biodiesel from soybean oil: experimental procedure of transesterification for organic chemistry laboratories

    International Nuclear Information System (INIS)

    The transesterification procedure of triacylglycerides from soybean oil (in natura and waste oil) to give biodiesel was adapted to semi-micro laboratory scale as an additional experimental technique of nucleophilic acyl substitution for undergraduate courses in Chemistry and related areas. (author)

  10. Connecting Biology and Organic Chemistry Introductory Laboratory Courses through a Collaborative Research Project

    Science.gov (United States)

    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…

  11. Investigation of causes of differences in student performance on the topics of stereochemistry and reaction mechanisms in an undergraduate organic chemistry course

    Science.gov (United States)

    Krylova, Irina

    Students have a great deal of difficulty in understanding the concepts of chemistry, including organic chemistry. which results in high failure and repeat rates. The purpose of this study was to determine possible reasons for student failure in an undergraduate organic chemistry course. In particular, the study dealt with student difficulties in two concepts of undergraduate organic chemistry--stereochemistry and reaction mechanisms. Such possible reasons for student failure. as lack of logical or spatial abilities, lack of knowledge of general chemistry, lack of studying efforts and misconceptions, were under investigation. The study involved a combination of both a quantitative approach--statistical analysis of student performance, and a qualitative approach--analysis of student think-aloud interviews. A group of students at the Catholic University of America (22 students), Prince George's Community College (23 students) and Montgomery Community College (13 students) enrolled in an undergraduate organic chemistry course were participants in the study. Catholic University and community college students were treated as two separate groups. At the beginning of the study, student logical and spatial abilities, and knowledge of general chemistry were ascertained. After each of the stereochemistry and reaction mechanisms concepts were taught, students were given two separate achievement tests on these concepts. Statistical correlation between independent variables (logical and spatial abilities, knowledge of general chemistry, and studying efforts) and dependent variables (achievement in stereochemistry and reaction mechanisms) was investigated using regression analysis. A group of students was interviewed to ascertain their knowledge of the organic chemistry concepts, ways of reasoning and misconceptions. The results of the study showed that knowledge of general chemistry is the most important variable in both Catholic University and community college student

  12. Materials Chemistry

    CERN Document Server

    Fahlman, Bradley D

    2011-01-01

    The 2nd edition of Materials Chemistry builds on the strengths that were recognized by a 2008 Textbook Excellence Award from the Text and Academic Authors Association (TAA). Materials Chemistry addresses inorganic-, organic-, and nano-based materials from a structure vs. property treatment, providing a suitable breadth and depth coverage of the rapidly evolving materials field. The 2nd edition continues to offer innovative coverage and practical perspective throughout. After briefly defining materials chemistry and its history, seven chapters discuss solid-state chemistry, metals, semiconducting materials, organic "soft" materials, nanomaterials, and materials characterization. All chapters have been thoroughly updated and expanded with, for example, new sections on ‘soft lithographic’ patterning, ‘click chemistry’ polymerization, nanotoxicity, graphene, as well as many biomaterials applications. The polymer and ‘soft’ materials chapter represents the largest expansion for the 2nd edition. Each ch...

  13. Evaluated kinetic and photochemical data for atmospheric chemistry: Volume IV – gas phase reactions of organic halogen species

    Directory of Open Access Journals (Sweden)

    R. Atkinson

    2008-08-01

    Full Text Available This article, the fourth in the series, presents kinetic and photochemical data sheets evaluated by the IUPAC Subcommittee on Gas Kinetic Data Evaluation for Atmospheric Chemistry. It covers the gas phase and photochemical reactions of organic halogen species, which were last published in 1997, and were updated on the IUPAC website in 2006/07. The article consists of a summary sheet, containing the recommended kinetic parameters for the evaluated reactions, and four appendices containing the data sheets, which provide information upon which the recommendations are made.

  14. Evaluated kinetic and photochemical data for atmospheric chemistry: Volume II – gas phase reactions of organic species

    Directory of Open Access Journals (Sweden)

    R. Atkinson

    2006-01-01

    Full Text Available This article, the second in the series, presents kinetic and photochemical data evaluated by the IUPAC Subcommittee on Gas Kinetic Data Evaluation for Atmospheric Chemistry. It covers the gas phase and photochemical reactions of Organic species, which were last published in 1999, and were updated on the IUPAC website in late 2002, and subsequently during the preparation of this article. The article consists of a summary table of the recommended rate coefficients, containing the recommended kinetic parameters for the evaluated reactions, and eight appendices containing the data sheets, which provide information upon which the recommendations are made.

  15. Organic Chemistry of Southern Sources: Microwave Spectroscopy of Cha-MMS1 and IRAS 15194-5115

    Science.gov (United States)

    Cordiner, Martin; Charnley, Steven

    2011-01-01

    We report new spectra of molecule-rich sources in the southern hemisphere obtained using the 22-meter Mopra telescope. Spectra and maps are presented of organic molecules detected between 30 and 50 GHz in the young Class 0 protostar Chamaeleon MMS-1. The large abundances of polyynes, cyanopolyynes and methanol may be indicative of a warm carbon chemistry in the dense gas surrounding this protostar. Spectra are also presented from a 78-96 GHz scan of the carbon-rich AGB star IRAS 15194-5115, including new detections of HC5N, CCS and C13CH.

  16. New Mechanistic Insights on the Selectivity of Transition-Metal-Catalyzed Organic Reactions: The Role of Computational Chemistry.

    Science.gov (United States)

    Zhang, Xinhao; Chung, Lung Wa; Wu, Yun-Dong

    2016-06-21

    With new advances in theoretical methods and increased computational power, applications of computational chemistry are becoming practical and routine in many fields of chemistry. In organic chemistry, computational chemistry plays an indispensable role in elucidating reaction mechanisms and the origins of various selectivities, such as chemo-, regio-, and stereoselectivities. Consequently, mechanistic understanding improves synthesis and assists in the rational design of new catalysts. In this Account, we present some of our recent works to illustrate how computational chemistry provides new mechanistic insights for improvement of the selectivities of several organic reactions. These examples include not only explanations for the existing experimental observations, but also predictions which were subsequently verified experimentally. This Account consists of three sections discuss three different kinds of selectivities. The first section discusses the regio- and stereoselectivities of hydrosilylations of alkynes, mainly catalyzed by [Cp*Ru(MeCN)3](+) or [CpRu(MeCN)3](+). Calculations suggest a new mechanism that involves a key ruthenacyclopropene intermediate. This mechanism not only explains the unusual Markovnikov regio-selectivity and anti-addition stereoselectivity observed by Trost and co-workers, but also motivated further experimental investigations. New intriguing experimental observations and further theoretical studies led to an extension of the reaction mechanism. The second section includes three cases of meta-selective C-H activation of aryl compounds. In the case of Cu-catalyzed selective meta-C-H activation of aniline, a new mechanism that involves a Cu(III)-Ar-mediated Heck-like transition state, in which the Ar group acts as an electrophile, was proposed. This mechanism predicted a higher reactivity for more electron-deficient Ar groups, which was supported by experiments. For two template-mediated, meta-selective C-H bond activations catalyzed by

  17. New Mechanistic Insights on the Selectivity of Transition-Metal-Catalyzed Organic Reactions: The Role of Computational Chemistry.

    Science.gov (United States)

    Zhang, Xinhao; Chung, Lung Wa; Wu, Yun-Dong

    2016-06-21

    With new advances in theoretical methods and increased computational power, applications of computational chemistry are becoming practical and routine in many fields of chemistry. In organic chemistry, computational chemistry plays an indispensable role in elucidating reaction mechanisms and the origins of various selectivities, such as chemo-, regio-, and stereoselectivities. Consequently, mechanistic understanding improves synthesis and assists in the rational design of new catalysts. In this Account, we present some of our recent works to illustrate how computational chemistry provides new mechanistic insights for improvement of the selectivities of several organic reactions. These examples include not only explanations for the existing experimental observations, but also predictions which were subsequently verified experimentally. This Account consists of three sections discuss three different kinds of selectivities. The first section discusses the regio- and stereoselectivities of hydrosilylations of alkynes, mainly catalyzed by [Cp*Ru(MeCN)3](+) or [CpRu(MeCN)3](+). Calculations suggest a new mechanism that involves a key ruthenacyclopropene intermediate. This mechanism not only explains the unusual Markovnikov regio-selectivity and anti-addition stereoselectivity observed by Trost and co-workers, but also motivated further experimental investigations. New intriguing experimental observations and further theoretical studies led to an extension of the reaction mechanism. The second section includes three cases of meta-selective C-H activation of aryl compounds. In the case of Cu-catalyzed selective meta-C-H activation of aniline, a new mechanism that involves a Cu(III)-Ar-mediated Heck-like transition state, in which the Ar group acts as an electrophile, was proposed. This mechanism predicted a higher reactivity for more electron-deficient Ar groups, which was supported by experiments. For two template-mediated, meta-selective C-H bond activations catalyzed by

  18. Sunscreen synthesis and their immobilisation on polymethylmethacrylate: an integrated project in organic chemistry, polymer chemistry and photochemistry; Sintese de fotoprotetores e sua imobilizacao em poli(metacrilato de metilo): um projeto integrado de quimica organica, quimica de polimeros e fotoquimica

    Energy Technology Data Exchange (ETDEWEB)

    Murtinho, Dina Maria B.; Serra, Maria Elisa S.; Pineiro, Marta, E-mail: dmurtinho@ci.uc.p [Universidade de Coimbra (Portugal). Faculdade de Ciencias e Tecnologia. Dept. de Quimica

    2010-07-01

    Dibenzalacetone and other aldol condensation products are known sunscreens commonly used in cosmetics. This type of compounds can easily be prepared in an Organic Chemistry Lab by reaction of aldehydes with ketones in basic medium. These compounds can be incorporated in poly(methyl methacrylate) and used as UV light absorbers, for example in sunglasses. This project has the advantage of using inexpensive reagents which are readily available in Chemistry Laboratories. This experiment can also be a base starting point for discussions of organic, polymer and photochemistry topics. (author)

  19. Organic Chemistry and Biology: Chemical Biology Through the Eyes of Collaboration

    Science.gov (United States)

    Hruby, Victor J.

    2011-01-01

    From a scientific perspective, efforts to understand biology including what constitutes health and disease has become a chemical problem. However, chemists and biologists “see” the problems of understanding biology from different perspectives, and this has retarded progress in solving the problems especially as they relate to health and disease. This suggests that close collaboration between chemists and biologists is not only necessary but essential for progress in both the biology and chemistry that will provide solutions to the global questions of biology. This perspective has directed my scientific efforts for the past 45 years, and in this overview I provide my perspective of how the applications of synthetic chemistry, structural design, and numerous other chemical principles have intersected in my collaborations with biologists to provide new tools, new science, and new insights that were only made possible and fruitful by these collaborations. PMID:20000552

  20. Inserção do conceito de economia atômica no programa de uma disciplina de química orgânica experimental Inclusion of atom economy concept in an experimental organic chemistry undergraduate course

    Directory of Open Access Journals (Sweden)

    Leila Maria Oliveira Coelho Merat

    2003-10-01

    Full Text Available In this paper, the atom economy concepts are applied in a series of experiments during an experimental organic chemistry class, to implement "green chemistry" in an undergraduate course.

  1. Disentangling the effects of water chemistry and substratum structure on moss-dwelling unicellular and multicellular micro-organisms in spring-fens

    Directory of Open Access Journals (Sweden)

    Michal HORSÁK

    2011-09-01

    Full Text Available Water chemistry is known to be one of the most important factors controlling species composition of many macro-organisms in wetlands. It is unclear to what extent micro-organisms respond to water chemistry as compared to chemistry-mediated substratum structure. We explored how the assemblages of different groups of micro-organisms in bryophyte tufts of spring-fens were determined by water chemistry and substratum structure. The aim was to compare unicellular autotrophic diatoms, unicellular heterotrophic testate amoebae and multicellular heterotrophic monogonont rotifers. Assemblages of all three groups showed a strong compositional gradient correlated with water pH and conductivity, calcium concentration and dominance of Sphagnum. While a second strong gradient in species composition of diatoms and testate amoebae was explained by factors such as substratum structure and water content, that of rotifers remained unexplained. Unlike the other two groups, testate amoeba assemblages were significantly determined by phosphates. Nitrates and iron were important species composition determinants for diatoms. Rotifers differed from the other groups in that they did not respond significantly to silica, iron or nutrients. When variation caused by substratum characteristics and water chemistry were partitioned out, testate amoebae were controlled more by substratum, while rotifers and diatoms were controlled more by water chemistry. Variation explained by individual effects of substratum or water chemistry, as compared to shared effects, was much lower for rotifers than for testate amoebae and diatoms. Our results show that, in semi-terrestrial ecosystems, pH and calcium concentrations are generally the main drivers of variation in species composition of unicellular and multicellular microorganisms, mirroring well described patterns for macro-organisms, providing support for general ecological hypotheses. Other water chemistry variables differed between

  2. From Matter to Life:Chemistry?Chemistry!

    Institute of Scientific and Technical Information of China (English)

    Jean-Marie; LEHN

    2007-01-01

    1 Results Animate as well as inanimate matter,living organisms as well as materials,are formed of molecules and of the organized entities resulting from the interaction of molecules with each other.Chemistry provides the bridge between the molecules of inanimate matter and the highly complex molecular architectures and systems which make up living organisms. Synthetic chemistry has developed a very powerful set of methods for constructing ever more complex molecules.Supramolecular chemistry seeks to con...

  3. Carbon oxidation state as a metric for describing the chemistry of atmospheric organic aerosol

    Energy Technology Data Exchange (ETDEWEB)

    Massachusetts Institute of Technology; Kroll, Jesse H.; Donahue, Neil M.; Jimenez, Jose L.; Kessler, Sean H.; Canagaratna, Manjula R.; Wilson, Kevin R.; Altieri, Katye E.; Mazzoleni, Lynn R.; Wozniak, Andrew S.; Bluhm, Hendrik; Mysak, Erin R.; Smith, Jared D.; Kolb, Charles E.; Worsnop, Douglas R.

    2010-11-05

    A detailed understanding of the sources, transformations, and fates of organic species in the environment is crucial because of the central roles that organics play in human health, biogeochemical cycles, and Earth's climate. However, such an understanding is hindered by the immense chemical complexity of environmental mixtures of organics; for example, atmospheric organic aerosol consists of at least thousands of individual compounds, all of which likely evolve chemically over their atmospheric lifetimes. Here we demonstrate the utility of describing organic aerosol (and other complex organic mixtures) in terms of average carbon oxidation state (OSC), a quantity that always increases with oxidation, and is readily measured using state-of-the-art analytical techniques. Field and laboratory measurements of OSC , using several such techniques, constrain the chemical properties of the organics and demonstrate that the formation and evolution of organic aerosol involves simultaneous changes to both carbon oxidation state and carbon number (nC).

  4. Cold and controlled molecular collisions: a bridge from quantum physics to organic chemistry

    International Nuclear Information System (INIS)

    The fundamental dynamics of molecular collisions and reactions have challenged researchers for many years. This continues to drive the development of more informative experiments and more precise theoretical descriptions in physical chemistry and chemical physics. I will discuss two collision processes that we have studied with different techniques in my group. The first one is a fully quantum state-resolved inelastic collision, which we have achieved to study in a low-temperature ion trap. The second one is the elementary nucleophilic substitution reaction, for which we have been able to image and analyse several different reaction mechanisms. (author)

  5. ORGANIC CHEMISTRY. Iron-catalyzed intermolecular [2+2] cycloadditions of unactivated alkenes.

    Science.gov (United States)

    Hoyt, Jordan M; Schmidt, Valerie A; Tondreau, Aaron M; Chirik, Paul J

    2015-08-28

    Cycloadditions, such as the [4+2] Diels-Alder reaction to form six-membered rings, are among the most powerful and widely used methods in synthetic chemistry. The analogous [2+2] alkene cycloaddition to synthesize cyclobutanes is kinetically accessible by photochemical methods, but the substrate scope and functional group tolerance are limited. Here, we report iron-catalyzed intermolecular [2+2] cycloaddition of unactivated alkenes and cross cycloaddition of alkenes and dienes as regio- and stereoselective routes to cyclobutanes. Through rational ligand design, development of this base metal-catalyzed method expands the chemical space accessible from abundant hydrocarbon feedstocks.

  6. ORGANIC CHEMISTRY. Catalytic asymmetric hydroamination of unactivated internal olefins to aliphatic amines.

    Science.gov (United States)

    Yang, Yang; Shi, Shi-Liang; Niu, Dawen; Liu, Peng; Buchwald, Stephen L

    2015-07-01

    Catalytic assembly of enantiopure aliphatic amines from abundant and readily available precursors has long been recognized as a paramount challenge in synthetic chemistry. Here, we describe a mild and general copper-catalyzed hydroamination that effectively converts unactivated internal olefins—an important yet unexploited class of abundant feedstock chemicals—into highly enantioenriched α-branched amines (≥96% enantiomeric excess) featuring two minimally differentiated aliphatic substituents. This method provides a powerful means to access a broad range of advanced, highly functionalized enantioenriched amines of interest in pharmaceutical research and other areas.

  7. The 1953 Stanley L. Miller Experiment: Fifty Years of Prebiotic Organic Chemistry

    Science.gov (United States)

    Lazcano, Antonio; Bada, Jeffrey L.

    2003-01-01

    The field of prebiotic chemistry effectively began with a publication in Science 50 years ago by Stanley L. Miller on the spark discharge synthesis of amino acids and other compounds using a mixture of reduced gases that were thought to represent the components of the atmosphere on the primitive Earth. On the anniversary of this landmark publication, we provide here an accounting of the events leading to the publication of the paper. We also discuss the historical aspects that lead up to the landmark Miller experiment.

  8. Clean graphene electrodes on organic thin-film devices via orthogonal fluorinated chemistry.

    Science.gov (United States)

    Beck, Jonathan H; Barton, Robert A; Cox, Marshall P; Alexandrou, Konstantinos; Petrone, Nicholas; Olivieri, Giorgia; Yang, Shyuan; Hone, James; Kymissis, Ioannis

    2015-04-01

    Graphene is a promising flexible, highly transparent, and elementally abundant electrode for organic electronics. Typical methods utilized to transfer large-area films of graphene synthesized by chemical vapor deposition on metal catalysts are not compatible with organic thin-films, limiting the integration of graphene into organic optoelectronic devices. This article describes a graphene transfer process onto chemically sensitive organic semiconductor thin-films. The process incorporates an elastomeric stamp with a fluorinated polymer release layer that can be removed, post-transfer, via a fluorinated solvent; neither fluorinated material adversely affects the organic semiconductor materials. We used Raman spectroscopy, atomic force microscopy, and scanning electron microscopy to show that chemical vapor deposition graphene can be successfully transferred without inducing defects in the graphene film. To demonstrate our transfer method's compatibility with organic semiconductors, we fabricate three classes of organic thin-film devices: graphene field effect transistors without additional cleaning processes, transparent organic light-emitting diodes, and transparent small-molecule organic photovoltaic devices. These experiments demonstrate the potential of hybrid graphene/organic devices in which graphene is deposited directly onto underlying organic thin-film structures.

  9. Laboratory Studies of the Reactive Chemistry and Changing CCN Properties of Secondary Organic Aerosol, Including Model Development

    Energy Technology Data Exchange (ETDEWEB)

    Scot Martin

    2013-01-31

    The chemical evolution of secondary-organic-aerosol (SOA) particles and how this evolution alters their cloud-nucleating properties were studied. Simplified forms of full Koehler theory were targeted, specifically forms that contain only those aspects essential to describing the laboratory observations, because of the requirement to minimize computational burden for use in integrated climate and chemistry models. The associated data analysis and interpretation have therefore focused on model development in the framework of modified kappa-Koehler theory. Kappa is a single parameter describing effective hygroscopicity, grouping together several separate physicochemical parameters (e.g., molar volume, surface tension, and van't Hoff factor) that otherwise must be tracked and evaluated in an iterative full-Koehler equation in a large-scale model. A major finding of the project was that secondary organic materials produced by the oxidation of a range of biogenic volatile organic compounds for diverse conditions have kappa values bracketed in the range of 0.10 +/- 0.05. In these same experiments, somewhat incongruently there was significant chemical variation in the secondary organic material, especially oxidation state, as was indicated by changes in the particle mass spectra. Taken together, these findings then support the use of kappa as a simplified yet accurate general parameter to represent the CCN activation of secondary organic material in large-scale atmospheric and climate models, thereby greatly reducing the computational burden while simultaneously including the most recent mechanistic findings of laboratory studies.

  10. Synthesis of a Parkinson's Disease Treatment Drug, the "R,R"-Tartrate Salt "of R"-Rasagiline: A Three Week Introductory Organic Chemistry Lab Sequence

    Science.gov (United States)

    Aguilar, Noberto; Garcia, Billy; Cunningham, Mark; David, Samuel

    2016-01-01

    A synthesis of the "R,R"-tartrate salt of the popular anti-Parkinson's drug "R"-rasagiline (Azilect) was adapted to introduce the organic laboratory student to a medically relevant synthesis. It makes use of concepts found in the undergraduate organic chemistry curriculum, appropriately fits into three approximately 4 h lab…

  11. CHINESE JOURNAL OF CHEMISTRY

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@Chinese Journal of Chemistry is an international journal published in English by the Chinese Chemical Society with its editorial office hosted by Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences.

  12. The Molecular Modeling Workbook for Organic Chemistry (by Warren J. Hehre, Alan J. Shusterman, and Janet E. Nelson)

    Science.gov (United States)

    Crouch, R. David

    1999-09-01

    Wavefunction, Inc.: Irvine, CA, 1998. 307 pp. ISBN 1-890661-06-6. 30.00. This workbook is the latest in a series of "lab manuals" designed to increase the presence of molecular modeling and computational chemistry in undergraduate courses. The authors have designed the workbook to differ from its predecessors in two ways: the target audience is introductory organic chemistry students, and a CD-ROM containing files of molecules and data replaces the need for expensive molecular modeling software. It also differs from its predecessors in that the exercises in it are not really molecular modeling experiments. Instead, students are introduced to the field by viewing the results of computational work stored on the CD-ROM. The workbook is divided into 21 chapters, each of which covers a topic encountered in introductory-level organic chemistry. The sequence of chapters follows the sequence of topics that instructors of introductory organic courses might employ, allowing the workbook to be used with most modern organic chemistry texts. The heart of the workbook, though, is the CD-ROM included with the book. It contains files of molecules and their accompanying computational results as well as Spartan View, a software package that allows these models to be visualized. Although it does not allow actual calculations to be performed, Spartan View permits the user to rotate molecules, intermediates, and transition states and retrieve "precalculated" values of bond and dihedral angles, bond lengths, energies, dipole moments, charge, and frequency of vibration. Spartan View also allows the user to search molecules and intermediates for electron-rich or electron-poor regions by showing electrostatic potential as well as HOMOs and LUMOs. Some files allow for animation of reactions or conformational changes. Note, however, that since the data are just stored on the CD-ROM, not all the data are available for all files. Although performing calculations is not an option, Spartan View

  13. The fate or organic matter during planetary accretion - Preliminary studies of the organic chemistry of experimentally shocked Murchison meteorite

    Science.gov (United States)

    Tingle, Tracy N.; Tyburczy, James A.; Ahrens, Thomas J.; Becker, Christopher H.

    1992-01-01

    The fate of organic matter in carbonaceous meteorites during hypervelocity (1-2 km/sec) impacts is investigated using results of experiments in which three samples of the Murchison (CM2) carbonaceous chondrite were shocked to 19, 20, and 36 GPa and analyzed by highly sensitive thermal-desorption photoionization mass spectrometry (SALI). The thermal-desorptive SALI mass spectra of unshocked CM2 material revealed presence of indigenous aliphatic, aromatic, sulfur, and organosulfur compounds, and samples shocked to about 20 GPa showed little or no loss of organic matter. On the other hand, samples shocked to 36 GPa exhibited about 70 percent loss of organic material and a lower alkene/alkane ratio than did the starting material. The results suggest that it is unlikely that the indigenous organic matter in carbonaceous chondritelike planetesimals could have survived the impact on the earth in the later stages of earth's accretion.

  14. Annual report 1988 Chemistry Department

    International Nuclear Information System (INIS)

    This report contains a brief survey of the main activities in the Chemistry Department. The names and abstracts of all articles and reports published and lectures given in 1988 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry, environmental chemistry, polymer chemistry, chemical reactivity, mineral processing, and general. (author)

  15. Annual report 1989 Chemistry Department

    International Nuclear Information System (INIS)

    This report contains a brief survey of the main activities in the Chemistry Department. The names and abstracts of all articles and reports published and lectures given in 1989 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry, environmental chemistry, polymer chemistry, chemical reactivity, mineral processing, and general. (author)

  16. Annual report 1986 chemistry department

    International Nuclear Information System (INIS)

    This report contains a brief survey of the main activities in the Chemistry Department. All articles and reports published and lectures given in 1986 are presented. The facilities and equipment are mentioned briefly. The activities are divided into the following groups: radioisotope chemistry, analytical- and organic chemistry, environmental chemistry, polymer chemistry, radical chemistral, mineral processing, and general. (author)

  17. A Green Multicomponent Reaction for the Organic Chemistry Laboratory: The Aqueous Passerini Reaction

    Science.gov (United States)

    Hooper, Matthew M.; DeBoef, Brenton

    2009-01-01

    Water is the ideal green solvent for organic reactions. However, most organic molecules are insoluble in it. Herein, we report a laboratory module that takes advantage of this property. The Passerini reaction, a three-component coupling involving an isocyanide, aldehyde, and carboxylic acid, typically requires [similar to] 24 h reaction times in…

  18. The Role of Heterogeneous Chemistry of Volatile ORganic Compounds: A Modeling and Laboratory Study

    Energy Technology Data Exchange (ETDEWEB)

    Gregory R. Carmichael; Vicki H. Grassian

    2007-03-01

    Overview The outputs of this research have been reported annually via the RIMS system. This report serves as an update and final report. The focus of our DOE BES funded project is on the importance of heterogeneous reactions in the troposphere. The primary objectives of our study were to: (i) Evaluate the extent to which heterogeneous chemistry affects the photochemical oxidant cycle, particularly, sources and sinks of tropospheric ozone; and (ii) Conduct laboratory studies on heterogeneous reactions involving NOy, O3 and VOCs on aerosol surfaces. These objectives were pursued through a multidisciplinary approach that combines modeling and laboratory components as discussed in more detail below. In addition, in response to the reconfiguring of the Atmospheric Science Program to focus on aerosol radiative forcing of climate, we also began to investigate the radiative properties of atmospheric aerosol.

  19. Function of Nanocatalyst in Chemistry of Organic Compounds Revolution: An Overview

    Directory of Open Access Journals (Sweden)

    Kanagarajan Hemalatha

    2013-01-01

    Full Text Available Heterocyclic motif is an important scaffold which has both industrial and pharmaceutical applications. These motifs can be prepared using wide variety of reaction conditions such as the use of expensive catalyst, toxic solvent, harsh reaction condition like the use of base, high temperature, and multistep reaction. Although various methods are involved, the chemistry arena is now shifted towards the greener way of synthesis. Nanocatalyst constitutes an important role in the green synthesis. This is because the activity of the catalyst resides in the exposed portion of the particles. By decreasing the size of the catalyst, advantages such as more surface area would be exposed to the reactant, only negligible amount would be required to give the significant result and selectivity could be achieved, thereby, eliminating the undesired products. The current review enlists the various types of nanocatalyst involved in the heterocyclic ring formation and also some other important functionalization over the ring.

  20. Giant planets: Clues on current and past organic chemistry in the outer solar system

    Science.gov (United States)

    Pollack, James B.; Atreya, Sushil K.

    1992-01-01

    The giant planets of the outer solar system - Jupiter, Saturn, Uranus, and Neptune - were formed in the same flattened disk of gas and dust, the solar nebula, as the terrestrial planets were. Yet, the giant planets differ in some very fundamental ways from the terrestrial planets. Despite enormous differences, the giant planets are relevant to exobiology in general and the origin of life on the Earth in particular. The giant planets are described as they are today. Their basic properties and the chemistry occurring in their atmospheres is discussed. Theories of their origin are explored and aspects of these theories that may have relevance to exobiology and the origin of life on Earth are stressed.

  1. Exploration and practice of teaching for organic chemistry experiment%有机化学实验教学的探索与实践

    Institute of Scientific and Technical Information of China (English)

    解正峰

    2011-01-01

    The organic chemistry experiment is one of most important parts of organic chemistry. In view of the current existing problems in organic chemistry experiment, the experimental content, teaching content, teaching methods and assessment methods have been explored and initial results are achieved.%有机化学实验是有机化学的重要组成部分,针对目前有机化学实验教学中存在的问题,在实验内容、教学内容、教学方法和考核方法等方面进行了改革探索,并取得了初步的效果.

  2. From energy-rich phosphate compounds to warfare agents: A review on the chemistry of organic phosphate compounds

    Directory of Open Access Journals (Sweden)

    Luciano Albino Giusti

    2008-12-01

    Full Text Available The chemistry of the phosphorus-oxygen bond is widely used in biological systems in many processes, such as energy transduction and the storage, transmission and expression of genetic information, which are essential to living beings in relation to a wide variety of functions. Compounds containing this bond have been designed for many purposes, ranging from agricultural defense systems, in order to increase food production, to nerve agents, for complaining use in warfare. In this review, features related to the chemistry of organic phosphate compounds are discussed, with particular emphasis on the role of phosphate compounds in biochemical events and in nerve agents. To this aim, the energy-rich phosphate compounds are focused, particularly the mode of their use as energy currency in cells. Historical and recent studies carried out by research groups have tried to elucidate the mechanism of action of enzymes responsible for energy transduction through the use of biochemical studies, enzyme models, and artificial enzymes. Finally, recent studies on the detoxification of nerve agents based on phosphorous esters are presented, and on the utilization of chromogenic and fluorogenic chemosensors for the detection of these phosphate species.

  3. High Throughput and High Speed Organic Synthesis in Drug Discovery:An Integration of Chemistry and Technology

    Institute of Scientific and Technical Information of China (English)

    Li Chen

    2004-01-01

    Drug discovery is a complicated process that involves multiple synthetic chemistry tasks.Among them, lead generation and optimization is the core business in the discovery research.During the stage of lead generation, a large library of many thousands individual compounds will be screened against a biological target to identify a set of hits that showed desirable activity. Once a hit has been identified, analog synthesis and development of SAR around this hit and establishment of relationship between targeted protein and its cellular function become the key activity in the drug discovery project. During this process, focused libraries of a few hundred compounds (X00) will be synthesized and tested. For synthetic chemistry tasks, the efficiency can be enhanced through "parallel processing or high throughput chemisay" using automation technology with which a large number of compounds can be synthesized, purified and plated at same time for biological and pharmaceutical screenings. To accelerate the lead optimization high speed synthesis is conducted when necessary and to improve "single process" efficiency using automation technology, when the rate limiting step become developing synthetic method to produce large amount of compounds (in gram quantity) that can be used in vivo pharmacology study. With these in mind, we designed integrated HTC technology platform which supports the key chemical synthesis activities in discovery research. In this presentation, several examples will be presented to illustrate the applications of high throughput and high speed organic synthesis in drug discovery.

  4. 药用有机化学试卷分析与教学改革思考①%Analysis of the organic chemistry examination paper and the enlightenment of teaching reform

    Institute of Scientific and Technical Information of China (English)

    孙晶; 张国民; 李桂香

    2014-01-01

    The organic chemistry examination test paper was analyzed, the countermeasures of teaching reform of Organic chemistry were put forward by analyzing the problems in Organic chemistry teaching.%对有机化学考试试卷进行了分析,针对试卷反映出的问题,提出了一些相应的教学改革措施。

  5. Organic reactions for the electrochemical and photochemical production of chemical fuels from CO_2 – The reduction chemistry of carboxylic acids and derivatives as bent CO_2 surrogates

    OpenAIRE

    Luca, Oana R.; Fenwick, Aidan Q.

    2015-01-01

    The present review covers organic transformations involved in the reduction of CO_2 to chemical fuels. In particular, we focus on reactions of CO_2 with organic molecules to yield carboxylic acid derivatives as a first step in CO_2 reduction reaction sequences. These biomimetic initial steps create opportunities for tandem electrochemical/chemical reductions. We draw parallels between long-standing knowledge of CO_2 reactivity from organic chemistry, organocatalysis, surface science and elect...

  6. System approach to organization of the corrosion and erosion monitoring and water chemistry testing at NPP

    International Nuclear Information System (INIS)

    The concept on corrosion monitoring of the NPPs with WWER-640 reactors, including three hierarchic levels, is described. Organization of computerized subsystem of chemical control in the composition of the NPPs power units control and management is shown

  7. Applications of the Conceptual Density Functional Theory Indices to Organic Chemistry Reactivity.

    Science.gov (United States)

    Domingo, Luis R; Ríos-Gutiérrez, Mar; Pérez, Patricia

    2016-06-09

    Theoretical reactivity indices based on the conceptual Density Functional Theory (DFT) have become a powerful tool for the semiquantitative study of organic reactivity. A large number of reactivity indices have been proposed in the literature. Herein, global quantities like the electronic chemical potential μ, the electrophilicity ω and the nucleophilicity N indices, and local condensed indices like the electrophilic P k + and nucleophilic P k - Parr functions, as the most relevant indices for the study of organic reactivity, are discussed.

  8. Unified Microscopic-Macroscopic Monte Carlo Simulations of Complex Organic Molecule Chemistry in Cold Cores

    OpenAIRE

    Chang, Qiang; Herbst, Eric

    2016-01-01

    The recent discovery of methyl formate and dimethyl ether in the gas phase of cold cores with temperatures as cold as 10 K challenges our previous astrochemical models concerning the formation of complex organic molecules. The strong correlation between the abundances and distributions of methyl formate and dimethyl ether further shows that current astrochemical models may be missing important chemical processes in cold astronomical sources. We investigate a scenario in which complex organic ...

  9. Influence of surface chemistry on the structural organization of monomolecular protein layers adsorbed to functionalized aqueous interfaces

    DEFF Research Database (Denmark)

    Lösche, M.; Piepenstock, M.; Diederich, A.;

    1993-01-01

    The molecular organization of streptavidin (SA) bound to aqueous surface monolayers of biotin-functionalized lipids and binary lipid mixtures has been investigated with neutron reflectivity and electron and fluorescence microscopy. The substitution of deuterons (2H) for protons (1H), both...... in subphase water molecules and in the alkyl chains of the lipid surface monolayer, was utilized to determine the interface structure on the molecular length scale. In all cases studied, the protein forms monomolecular layers underneath the interface with thickness values of apprx 40 ANG . A systematic...... dependence of the structural properties of such self-assembled SA monolayers on the surface chemistry was observed: the lateral protein density depends on the length of the spacer connecting the biotin moiety and its hydrophobic anchor. The hydration of the lipid head groups in the protein-bound state...

  10. Synthesis of a Two-Dimensional Covalent Organic Monolayer through Dynamic Imine Chemistry at the Air/Water Interface.

    Science.gov (United States)

    Dai, Wenyang; Shao, Feng; Szczerbiński, Jacek; McCaffrey, Ryan; Zenobi, Renato; Jin, Yinghua; Schlüter, A Dieter; Zhang, Wei

    2016-01-01

    A two-dimensional covalent organic monolayer was synthesized from simple aromatic triamine and dialdehyde building blocks by dynamic imine chemistry at the air/water interface (Langmuir-Blodgett method). The obtained monolayer was characterized by optical microscopy, scanning electron microscopy, and atomic force microscopy, which unambiguously confirmed the formation of a large (millimeter range), unimolecularly thin aromatic polyimine sheet. The imine-linked chemical structure of the obtained monolayer was characterized by tip-enhanced Raman spectroscopy, and the peak assignment was supported by spectra simulated by density functional theory. Given the modular nature and broad substrate scope of imine formation, the work reported herein opens up many new possibilities for the synthesis of customizable 2D polymers and systematic studies of their structure-property relationships.

  11. Two Principles of Reticular Chemistry Uncovered in a Metal-Organic Framework of Heterotritopic Linkers and Infinite Secondary Building Units.

    Science.gov (United States)

    Catarineu, Noelle R; Schoedel, Alexander; Urban, Philipp; Morla, Maureen B; Trickett, Christopher A; Yaghi, Omar M

    2016-08-31

    Structural diversity of metal-organic frameworks (MOFs) has been largely limited to linkers with at most two different types of coordinating groups. MOFs constructed from linkers with three or more nonidentical coordinating groups have not been explored. Here, we report a robust and porous crystalline MOF, Zn3(PBSP)2 or MOF-910, constructed from a novel linker PBSP (phenylyne-1-benzoate, 3-benzosemiquinonate, 5-oxidopyridine) bearing three distinct types of coordinative functionality. The MOF adopts a complex and previously unreported topology termed tto. Our study suggests that simple, symmetric linkers are not a necessity for formation of crystalline extended structures and that new, more complex topologies are attainable with irregular, heterotopic linkers. This work illustrates two principles of reticular chemistry: first, selectivity for helical over straight rod secondary building units (SBUs) is achievable with polyheterotopic linkers, and second, the pitch of the resulting helical SBUs may be fine-tuned based on the metrics of the polyheterotopic linker.

  12. Two Principles of Reticular Chemistry Uncovered in a Metal-Organic Framework of Heterotritopic Linkers and Infinite Secondary Building Units.

    Science.gov (United States)

    Catarineu, Noelle R; Schoedel, Alexander; Urban, Philipp; Morla, Maureen B; Trickett, Christopher A; Yaghi, Omar M

    2016-08-31

    Structural diversity of metal-organic frameworks (MOFs) has been largely limited to linkers with at most two different types of coordinating groups. MOFs constructed from linkers with three or more nonidentical coordinating groups have not been explored. Here, we report a robust and porous crystalline MOF, Zn3(PBSP)2 or MOF-910, constructed from a novel linker PBSP (phenylyne-1-benzoate, 3-benzosemiquinonate, 5-oxidopyridine) bearing three distinct types of coordinative functionality. The MOF adopts a complex and previously unreported topology termed tto. Our study suggests that simple, symmetric linkers are not a necessity for formation of crystalline extended structures and that new, more complex topologies are attainable with irregular, heterotopic linkers. This work illustrates two principles of reticular chemistry: first, selectivity for helical over straight rod secondary building units (SBUs) is achievable with polyheterotopic linkers, and second, the pitch of the resulting helical SBUs may be fine-tuned based on the metrics of the polyheterotopic linker. PMID:27517606

  13. The influence of natural organic matter on power plant cycle chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Gericke, Gerhard [Eskom, Cleveland (South Africa). Research and Innovation Dept.; Aspden, J. Denis

    2009-03-15

    The improvement of condensate and feedwater quality in power generating plant is an on-going process in the power industry in light of the ever increasing use of high pressure and temperature boiler and turbine systems. One area of research that has become very topical is the removal of natural organic matter from power station make-up water. Where potable water is produced, which is also of concern to Eskom, the presence of organics can also lead to taste and colour problems, they can act as precursors for the formation of disinfection by-products and they can stabilise dispersed and colloidal particles during the clarification process. Although water demineralisation processes can cope with the removal of inorganic salts from raw water, the removal of organic matter poses a far greater problem. Some organic compounds can be removed via the ion exchange process, however fouling of the anion exchange resin, and to a lesser extent of the cation exchange resin, occurs during this process which can have an impact on the overall performance of the water treatment plant. Those organics that are not removed will find their way into the steam/water circuit, where they are decomposed through thermohydraulic processes, and these decomposition by-products can influence the quality of the steam and condensate. The mechanistic impact of organic matter on the materials of construction of the steam/condensate cycle is a very controversial issue and the aim of this paper is therefore not to contribute to this debate, but rather to demonstrate the impact of organics on treatment processes and the quality of the water in the steam cycle. (orig.)

  14. Meteor wake in high frame-rate images--implications for the chemistry of ablated organic compounds

    Science.gov (United States)

    Jenniskens, Peter; Stenbaek-Nielsen, Hans C.

    2004-01-01

    Extraterrestrial organic matter may have been chemically altered into forms more ameanable for prebiotic chemistry in the wake of a meteor after ablation. We measured the rate of cooling of the plasma in the meteor wake from the intensity decay just behind a meteoroid by freezing its motion in high frame-rate 1000 frames/s video images, with an intensified camera that has a short phosphor decay time. Though the resulting cooling rate was found to be lower than theoretically predicted, our calculations indicated that there would have been insufficient collisions to break apart large organic compounds before most reactive radicals and electrons were lost from the air plasma. Organic molecules delivered from space to the early Earth via meteors might therefore have survived in a chemically altered form. In addition, we discovered that relatively small meteoroids generated far-ultraviolet emission that is absorbed in the immediate environment of the meteoroid, which may chemically alter the atmosphere over a much larger region than previously recognized.

  15. A química orgânica na consolidação dos conceitos de átomo e molécula Organic chemistry in the consolidation of the concepts of atom and molecule

    Directory of Open Access Journals (Sweden)

    Tânia de Oliveira Camel

    2009-01-01

    Full Text Available The present work discusses the appearance of the concepts of valence and molecular structure, and describes the appropriation and evolution of the concept of molecule in the period following the publication of Avogadro's Hypothesis. The point of reference is the development of what became known as Organic Chemistry, which encompassed Pharmacy, Physiological Chemistry, Animal and Plant Chemistry, Chemistry of Dyestuffs, Agricultural Chemistry, and the fledgling Organic Synthesis industry in the early 19th century. The theories formulated in these areas and the quest for accurate atomic weights led to those concepts of valence and molecular structure and to a precise differentiation between atom and molecule.

  16. Chemistry of organic carbon in soil with relationship to the global carbon cycle

    International Nuclear Information System (INIS)

    Various ecosystem disturbances alter the balances between production of organic matter and its decomposition and therefore change the amount of carbon in soil. The most severe perturbation is conversion of natural vegetation to cultivated crops. Conversion of natural vegetation to cultivated crops results in a lowered input of slowly decomposing material which causes a reduction in overall carbon levels. Disruption of soil matrix structure by cultivation leads to lowered physical protection of organic matter resulting in an increased net mineralization rate of soil carbon. Climate change is another perturbation that affects the amount and composition of plant production, litter inputs, and decomposition regimes but does not affect soil structure directly. Nevertheless, large changes in soil carbon storage are probable with anticipated CO2 induced climate change, particularly in northern latitudes where anticipated climate change will be greatest (MacCracken and Luther 1985) and large amounts of soil organic matter are found. It is impossible, given the current state of knowledge of soil organic matter processes and transformations to develop detailed process models of soil carbon dynamics. Largely phenomenological models appear to be developing into predictive tools for understanding the role of soil organic matter in the global carbon cycle. In particular, these models will be useful in quantifying soil carbon changes due to human land-use and to anticipated global climate and vegetation changes. 47 refs., 7 figs., 2 tabs

  17. Extraterrestrial Organic Chemistry: From the Interstellar Medium to the Origins of Life

    Science.gov (United States)

    Pohorille, Andrew; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    Extraterrestrially delivered organics in the origin of cellular life. Various processes leading to the emergence of cellular life from organics delivered from space to earth or other planetary bodies in the solar system will be reviewed. The focus will be on: (1) self-assembly of amphiphilic material to vesicles and other structures, such as micelles and multilayers, and its role in creating environments suitable for chemical catalysis, (2) a possible role of extraterrestrial delivery of organics in the formation of the simplest bioenergetics (3) mechanisms leading from amino acids or their precursors to simple peptides and, subsequently, to the evolution of metabolism. These issues will be discussed from two opposite points of view: (1) Which molecules could have been particularly useful in the protobiological evolution; this may provide focus for searching for these molecules in interstellar media. (2) Assuming that a considerable part of the inventory of organic matter on the early earth was delivered extraterrestrially, what does relative abundance of different organics in space tell us about the scenario leading to the origin of life.

  18. Fast Quantum Molecular Dynamics Simulations of Shock-induced Chemistry in Organic Liquids

    Science.gov (United States)

    Cawkwell, Marc

    2014-03-01

    The responses of liquid formic acid and phenylacetylene to shock compression have been investigated via quantum-based molecular dynamics simulations with the self-consistent tight-binding code LATTE. Microcanonical Born-Oppenheimer trajectories with precise conservation of the total energy were computed without relying on an iterative self-consistent field optimization of the electronic degrees of freedom at each time step via the Fast Quantum Mechanical Molecular Dynamics formalism [A. M. N. Niklasson and M. J. Cawkwell, Phys. Rev. B, 86, 174308 (2012)]. The conservation of the total energy in our trajectories was pivotal for the capture of adiabatic shock heating as well as temperature changes arising from endo- or exothermic chemistry. Our self-consistent tight-binding parameterizations yielded very good predictions for the gas-phase geometries of formic acid and phenylacetylene molecules and the principal Hugoniots of the liquids. In accord with recent flyer-plate impact experiments, our simulations revealed i) that formic acid reacts at relatively low impact pressures but with no change in volume between products and reactants, and ii) a two-step polymerization process for phenylacetylene. Furthermore, the evolution of the HOMO-LUMO gap tracked on-the-fly during our simulations could be correlated with changes transient absorption measured during laser-driven shock compression experiments on these liquids.

  19. Organic chemistry of natural products in Indonesia: Opportunity, achievement and challenges

    Science.gov (United States)

    Achmad, Sjamsul Arifin; Hakim, Euis Holisotan; Juliawaty, Lia Dewi; Makmur, Lukman; Syah, Yana Maolana; Mujahidin, Didin

    2015-09-01

    Of the 250.000 species of higher plants known to exist on earth, 30.000 species are to be found in the tropical region of Indonesia. Many of these tropical plants have been employed as medicines by the indigeneous people in both rural and urban areas. However, only a relatively small amount of them have been thoroughly studied for all aspects of their potential therapeutic value in medicine. The search for plant chemicals with potential activity for treatment of deseases and industrial utilization have been initiated successfully in our laboratories. in combination with biological evaluation. Many members of the genus Artocarpus and Morus (Moraceae) are used in tradirional folk medicine in the tropical and subtropical regions of south and southeast Asia. In this paper, our recent works on the chemistry of Artocarpus lanceifolius and Morus macroura the endemic and endangered species to Indonesia, which led to the isolation of many new, unique and novel phenolic compounds and their bioactivities will be presented.

  20. Organic Chemistry in Interstellar Ices: Connection to the Comet Halley Results

    Science.gov (United States)

    Schutte, W. A.; Agarwal, V. K.; deGroot, M. S.; Greenberg, J. M.; McCain, P.; Ferris, J. P.; Briggs, R.

    1997-01-01

    Mass spectroscopic measurements on the gas and dust in the coma of Comet Halley revealed the presence of considerable amounts of organic species. Greenberg (1973) proposed that prior to the formation of the comet UV processing of the ice mantles on grains in dense clouds could lead to the formation of complex organic molecules. Theoretical predictions of the internal UV field in dense clouds as well as the discovery in interstellar ices of species like OCS and OCN- which have been formed in simulation experiments by photoprocessing of interstellar ice analogues point to the importance of such processing. We undertook a laboratory simulation study of the formation of organic molecules in interstellar ices and their possible relevance to the Comet Halley results.

  1. Soil warming affects soil organic matter chemistry of all density fractions of a mountain forest soil

    Science.gov (United States)

    Schnecker, Jörg; Wanek, Wolfgang; Borken, Werner; Schindlbacher, Andreas

    2016-04-01

    Rising temperatures enhance microbial decomposition of soil organic matter (SOM) and increase thereby the soil CO2 efflux. Elevated microbial activity might differently affect distinct SOM pools, depending on their stability and accessibility. Soil fractions derived from density fractionation have been suggested to represent SOM pools with different turnover times and stability against microbial decomposition. We here investigated the chemical and isotopic composition of bulk soil and three different density fractions of forest soils from a long term warming experiment in the Austrian Alps. At the time of sampling the soils in this experiment had been warmed during the snow-free period for 8 consecutive years. During that time no thermal adaptation of the microbial community could be identified and CO2 release from the soil continued to be elevated by the warming treatment. Our results which included organic C content, total N content, δ13C, δ 14C, δ 15N and the chemical composition, identified by pyrolysis-GC/MS, showed no significant differences in bulk soil between warming treatment and control. The differences in the three individual fractions (free particulate organic matter, occluded particulate organic matter and mineral associated organic matter) were mostly small and the direction of warming induced change was variable with fraction and sampling depth. We did however find statistically significant effects of warming in all density fractions from 0-10 cm depth, 10-20 cm depth or both. Our results also including significant changes in the supposedly more stable mineral associated organic matter fraction where δ 13C values decreased at both sampling depths and the relative proportion of N-bearing compounds decreased at a sampling depth of 10-20 cm. All the observed changes can be attributed to an interplay of enhanced microbial decomposition of SOM and increased root litter input. This study suggests that soil warming destabilizes all density fractions of

  2. Applications of the Conceptual Density Functional Theory Indices to Organic Chemistry Reactivity

    Directory of Open Access Journals (Sweden)

    Luis R. Domingo

    2016-06-01

    Full Text Available Theoretical reactivity indices based on the conceptual Density Functional Theory (DFT have become a powerful tool for the semiquantitative study of organic reactivity. A large number of reactivity indices have been proposed in the literature. Herein, global quantities like the electronic chemical potential μ, the electrophilicity ω and the nucleophilicity N indices, and local condensed indices like the electrophilic P k + and nucleophilic P k − Parr functions, as the most relevant indices for the study of organic reactivity, are discussed.

  3. BIO-ORGANIC CHEMISTRY QUARTERLY REPORT. December 1962 throughFebruary 1963

    Energy Technology Data Exchange (ETDEWEB)

    Various

    1963-03-29

    This report covers the following titles: (1) A versatile solvent to replace phenol for the paper chromatography of radioactive intermediary metabolites; (2) Chromatography of plant lipids on alumina paper; (3) Quinone and pigment composition of chloroplasts and quantasomes from Spinacea oleracea; (4) The lipid composition of chloroplast lamellae from Spinacea oleracea; (5) Metal chelates and photochemistry of flavins; (6) Photoinduced ESR in some solutions of organic electron donors and acceptors; (7) Fluorescence of oriented dye-macromolecule complexes--Theoretical study; (8) Formation of adenine by electron irradiation of methane, ammonia, and water; (9) Uptake of organic compounds by planarians; (10) The planaria: Absorption spectrum, cell disaggregation, and studies on homogenates.

  4. An Epistemological Inquiry into Organic Chemistry Education: Exploration of Undergraduate Students' Conceptual Understanding of Functional Groups

    Science.gov (United States)

    Akkuzu, Nalan; Uyulgan, Melis Arzu

    2016-01-01

    This study sought to determine the levels of conceptual understanding of undergraduate students regarding organic compounds within different functional groups. A total of 60 students who were enrolled in the Department of Secondary Science and Mathematics Education of a Faculty of Education at a state university in Turkey and who had followed an…

  5. Green Chemistry Decision-Making in an Upper-Level Undergraduate Organic Laboratory

    Science.gov (United States)

    Edgar, Landon J. G.; Koroluk, Katherine J.; Golmakani, Mehrnaz; Dicks, Andrew P.

    2014-01-01

    A self-directed independent synthesis experiment was developed for a third-year undergraduate organic laboratory. Students were provided with the CAS numbers of starting and target compounds and devised a synthetic plan to be executed over two 4.5 h laboratory periods. They consulted the primary literature in order to develop and carry out an…

  6. Self-Assembling Amphiphilic Molecules: A Possible Relationship Between Interstellar Chemistry and Meteoritic Organics

    Science.gov (United States)

    Sandford, Scott A.; Dworkin, Jason P.; Deamer, David W.; Allamandola, Louis J.; DeVincenzi, Donald (Technical Monitor)

    2001-01-01

    Interstellar gas and dust comprise the primary material from which the solar system formed. Evidence that some of this material was organic in nature and survived incorporation into the protosolar nebula is provided by the presence of deuterium-enriched organics in meteorites and interplanetary dust particles. Once the inner planets had sufficiently cooled, late accretionary infall of meteoroids and cosmic dust must have seeded them with some of these complex organic compounds. Delivery of such extraterrestrial compounds may have contributed to the organic inventory necessary for the origin of life. Interstellar ices, the building blocks of comets, tie up a large fraction of the biogenic elements available in molecular clouds. In our efforts to understand their synthesis, chemical composition, and physical properties, we report here that a complex mixture of molecules is produced by ultraviolet (UV) photolysis of realistic, interstellar ice analogs, and that some of the components have properties relevant to the origin of life, including the ability to self-assemble into vesicular structures.

  7. Controlling embedment and surface chemistry of nanoclusters in metal-organic frameworks.

    Science.gov (United States)

    Coupry, D E; Butson, J; Petkov, P S; Saunders, M; O'Donnell, K; Kim, H; Buckley, C; Addicoat, M; Heine, T; Szilágyi, P Á

    2016-04-14

    A combined theoretical and experimental approach demonstrates that nanocluster embedment into the pores of metal-organic frameworks (MOF) may be influenced by the chemical functionalisation of the MOF. Furthermore, this results in the surface functionalisation of the embedded nanoclusters, highlighting the potential of MOF scaffolds for the design and synthesis of novel functional materials.

  8. Study of photochemical transformations of organic azides by matrix isolation techniques and quantum chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Gritsan, N P [Institute of Chemical Kinetics and Combustion, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2007-12-31

    Results of investigations of organic azide photochemistry in inert gas matrices and the most important spectroscopic studies of the last decade, which formed the basis for the modern views on the photochemistry of azides, are analysed. The unique potential of the matrix isolation technique for the reliable identification of reaction intermediates is demonstrated.

  9. Incorporation of Gas Chromatography-Mass Spectrometry into the Undergraduate Organic Chemistry Laboratory Curriculum

    Science.gov (United States)

    Giarikos, Dimitrios G.; Patel, Sagir; Lister, Andrew; Razeghifard, Reza

    2013-01-01

    Gas chromatography-mass spectrometry (GC-MS) is a powerful analytical tool for detection, identification, and quantification of many volatile organic compounds. However, many colleges and universities have not fully incorporated this technique into undergraduate teaching laboratories despite its wide application and ease of use in organic…

  10. Organic Molecules in the Galactic Center. Hot Core Chemistry without Hot Cores

    CERN Document Server

    Requena-Torres, M A; Martín, S; Martín-Pintado, J; Rodr'iguez-Fern'andez, N J; Rodríguez-Franco, A

    2006-01-01

    To study the origin of the large abundances of complex organic molecules in the Galactic center (GC), we have carried out a systematic study of the complex organic molecules CH3OH, C2H5OH, (CH3)2O, HCOOCH3, HCOOH, CH3COOH, H2CO and CS toward 40 GC molecular clouds. Using the LTE approximation, we have derived the physical properties of GC molecular clouds and the abundances of the complex molecules.The CH3OH abundance between clouds varies by nearly two orders of magnitude from 2.4x10^{-8} to 1.1x10^{-6}. The abundance of the other complex organic molecules relative to that of CH3OH is basically independent of the CH3OH abundance, with variations of only a factor of 4-8. The abundances of complex organic molecules in the GC are compared with those measured in hot cores and hot corinos, in which these complex molecules are also abundant. We find that both the abundance and the abundance ratios of the complex molecules relative to CH3OH in hot cores are similar to that found in the GC clouds. However, hot corin...

  11. The impact of building recirculation rates on secondary organic aerosols generated by indoor chemistry

    DEFF Research Database (Denmark)

    Zuraimi, M.S.; Weschler, Charles J.; Tham, K.W.;

    2007-01-01

    Numerous investigators have documented increases in the concentrations of airborne particles as a consequence of ozone/terpene reactions in indoor environments. This study examines the effect of building recirculation rates on the concentrations of secondary organic aerosol (SOA) resulting from r...

  12. Synthesis and Hydrogenation of Disubstituted Chalcones: A Guided-Inquiry Organic Chemistry Project

    Science.gov (United States)

    Mohrig, Jerry R.; Hammond, Christina Noring; Schatz, Paul F.; Davidson, Tammy A.

    2009-01-01

    Guided-inquiry experiments offer the same opportunities to participate in the process of science as classical organic qualitative analysis used to do. This three-week guided-inquiry project involves an aldol-dehydration synthesis of a chalcone chosen from a set of nine, followed by a catalytic transfer hydrogenation reaction using ammonium formate…

  13. Coupling Molecular Modeling to the Traditional "IR-ID" Exercise in the Introductory Organic Chemistry Laboratory

    Science.gov (United States)

    Stokes-Huby, Heather; Vitale, Dale E.

    2007-01-01

    This exercise integrates the infrared unknown identification ("IR-ID") experiment common to most organic laboratory syllabi with computer molecular modeling. In this modification students are still required to identify unknown compounds from their IR spectra, but must additionally match some of the absorptions with computed frequencies they…

  14. Secondary organic aerosol production from diesel vehicle exhaust: impact of aftertreatment, fuel chemistry and driving cycle

    Science.gov (United States)

    Gordon, T. D.; Presto, A. A.; Nguyen, N. T.; Robertson, W. H.; Na, K.; Sahay, K. N.; Zhang, M.; Maddox, C.; Rieger, P.; Chattopadhyay, S.; Maldonado, H.; Maricq, M. M.; Robinson, A. L.

    2014-05-01

    Environmental chamber ("smog chamber") experiments were conducted to investigate secondary organic aerosol (SOA) production from dilute emissions from two medium-duty diesel vehicles (MDDVs) and three heavy-duty diesel vehicles (HDDVs) under urban-like conditions. Some of the vehicles were equipped with emission control aftertreatment devices, including diesel particulate filters (DPFs), selective catalytic reduction (SCR) and diesel oxidation catalysts (DOCs). Experiments were also performed with different fuels (100% biodiesel and low-, medium- or high-aromatic ultralow sulfur diesel) and driving cycles (Unified Cycle,~Urban Dynamometer Driving Schedule, and creep + idle). During normal operation, vehicles with a catalyzed DPF emitted very little primary particulate matter (PM). Furthermore, photooxidation of dilute emissions from these vehicles produced essentially no SOA (below detection limit). However, significant primary PM emissions and SOA production were measured during active DPF regeneration experiments. Nevertheless, under reasonable assumptions about DPF regeneration frequency, the contribution of regeneration emissions to the total vehicle emissions is negligible, reducing PM trapping efficiency by less than 2%. Therefore, catalyzed DPFs appear to be very effective in reducing both primary PM emissions and SOA production from diesel vehicles. For both MDDVs and HDDVs without aftertreatment substantial SOA formed in the smog chamber - with the emissions from some vehicles generating twice as much SOA as primary organic aerosol after 3 h of oxidation at typical urban VOC / NOx ratios (3 : 1). Comprehensive organic gas speciation was performed on these emissions, but less than half of the measured SOA could be explained by traditional (speciated) SOA precursors. The remainder presumably originates from the large fraction (~30%) of the nonmethane organic gas emissions that could not be speciated using traditional one-dimensional gas chromatography. The

  15. Effect of soil organic matter chemistry on sorption of trinitrotoluene and 2,4-dinitrotoluene

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Neera, E-mail: drneerasingh@yahoo.com [Division of Agricultural Chemicals, Indian Agricultural Research Institute, New Delhi-110012 (India); Berns, Anne E. [Forschungszentrum Juelich GmbH, Institute of Chemistry and Dynamics of the Geosphere, Institute 4: Agrosphere, 52425 Juelich (Germany); Hennecke, Dieter; Hoerner, Jennifer; Koerdel, Werner [Fraunhofer Institute of Molecular Biology and Applied Ecology, 27392 Schmallenberg (Germany); Schaeffer, Andreas [RWTH University, Chair of Environmental Biology and Chemodynamics, Worringerweg 152074, Aachen (Germany)

    2010-01-15

    The sorption of organic contaminants in soil is mainly attributed to the soil organic matter (SOM) content. However, recent studies have highlighted the fact that it is not the total carbon content of the organic matter, but its chemical structure which have a profound effect on the sorption of organic contaminants. In the present study sorption of two nitroaromatic contaminants viz. trinitrotoluene (TNT) and 2,4-dinitrotoluene (2,4-DNT) was studied in different SOM fractions viz. a commercial humic acid, commercial lignin and humic acid and humin extracted from a compost. {sup 13}C-DP/MAS NMR studies indicated that the structural composition of the organic carbon in different SOM fractions was different. The order of sorption of the nitroaromatics in the different sorbents was: humic acid-commercial > humic acid-compost > humin {approx} lignin. Among the aliphatic and aromatic carbon fractions (representing bulk of SOM matrix), adsorption parameter K{sub f}(1/n) for nitroaromatics sorption correlated well with the aliphatic carbon (r = 0.791 for TNT and 0.829 for 2,4-DNT) than the aromatic carbon (r = 0.634 for TNT and r = 0.616 for 2,4-DNT). However, among carbon containing functional groups, carbonyl carbon showed strong positive correlation with sorption of TNT (r = 0.991) and 2,4-DNT (r = 0.967) while O-alkyl carbon showed negative correlation (r = 0.832 for TNT and r = 0.828 for 2,4-DNT). The study indicates that aliphatic domains in the SOM significantly affect the non-specific sorption of both the nitroaromatic contaminants.

  16. Electronic properties and chemistry of metal / organic semiconductor/ S-GaAs(100) heterosructures

    Energy Technology Data Exchange (ETDEWEB)

    Gavrila, G.N.

    2005-10-21

    in the framework of this thesis three perylene derivates are applied as interlayers in metal/organic layer/S-GaAs(100) heterostructures. The aim of this thesis is to prove the influence of different chemical end-groups on the electronic and chemical properties of the interfaces, as well as the molecular orientation in the organic layers. The molecules 3,4,9,10-perylene tetracarbonic acid dianhydride (PTCDA), 3,4,9,10-perylene tetracarbonic acid diimide (PTCDI), and dimethyl-3,4,9,10-perylene tetracarbonic acid diimide (DiMe-PTCDI) were evaporated by organic molecular beam deposition (OMBD) in the ultrahigh vacuum on sulfur-passivated GaAs(001):2 x 1 substrates. Surface-sensitive characterization procedures as photoemission spectroscopy (PES), inverse photoemission spectroscopy (IPES), and near-edge X-ray fine-structure measurements (NEXAFS) were applied for the characterization. Theoretical calculations by means of the density-functional methods were performed, in order to allow an assignment of different components in core-level spectra. The NEXAFS spectra allow a precise determination of the molecule orientation in relation to the substrate. So it can be proved that a small change of chemical end-groups for instance in DiMe-PTCDI compared with PTCDI causes a dramatic change of the molecule orientation. The valence-band spectra of DiMe-PTCDI show an energetic dispersion of 0.2 eV, which can be assigned to a {pi}-orbital overlap and covers the formation of valence bands. The energy-level fitting to the organic-layer/S-GaAs interface as well as the transport band gap of PTCDI, DiMe-PTCDI, and PTCDA were deteminde by means of PES and IPES. The electronic, chemical, and structural properties of metal/organic-layer interfaces were studied by means of core-level spectroscopy and NEXAFS. Mg reacts strongly with the end-groups of PTCDA AND ptcdi, while the In atoms contribute to a charge-transfer process with the perylene cores of all three molecules, whereby the

  17. Unified Microscopic-Macroscopic Monte Carlo Simulations of Complex Organic Molecule Chemistry in Cold Cores

    CERN Document Server

    Chang, Qiang

    2016-01-01

    The recent discovery of methyl formate and dimethyl ether in the gas phase of cold cores with temperatures as cold as 10 K challenges our previous astrochemical models concerning the formation of complex organic molecules. The strong correlation between the abundances and distributions of methyl formate and dimethyl ether further shows that current astrochemical models may be missing important chemical processes in cold astronomical sources. We investigate a scenario in which complex organic molecules and the methoxy radical can be formed on dust grains via a so-called "chain reaction" mechanism, in a similar manner to CO$_2$. A unified gas-grain microscopic-macroscopic Monte Carlo approach with both normal and interstitial sites for icy grain mantles is used to perform the chemical simulations. Reactive desorption with varying degrees of efficiency is included to enhance the non-thermal desorption of species formed on cold dust grains. In addition, varying degrees of efficiency for the surface formation of m...

  18. Optimal and sequential design for bridge regression with application in organic chemistry

    OpenAIRE

    Carnaby, Sarah

    2011-01-01

    This thesis presents and applies methods for the design and analysis of experiments for a family of coefficient shrinkage methods, known collectively as bridge regression, with emphasis on the two special cases of ridge regression and the lasso. The application is the problem of understanding and predicting the melting point of small molecule organic compounds using chemical descriptors. Experiments typically have a large number of predictors compared to the number of observations, and hig...

  19. Proto-Planetary Disk Chemistry Recorded by D-Rich Organic Radicals in Carbonaceous Chondrites

    OpenAIRE

    Remusat, Laurent; Robert, François; Meibom, Anders; Mostefaoui, Smail; Delpoux, Olivier; Binet, Laurent; Gourier, Didier; Derenne, Sylvie

    2009-01-01

    Insoluble organic matter (IOM) in primitive carbonaceous meteorites has preserved its chemical composition and isotopic heterogeneity since the solar system formed ~4.567 billion years ago. We have identified the carrier moieties of isotopically anomalous hydrogen in IOM isolated from the Orgueil carbonaceous chondrite. Data from high spatial resolution, quantitative isotopic NanoSIMS mapping of Orgueil IOM combined with data from electron paramagnetic resonance spectroscopy reveals that orga...

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

    OpenAIRE

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

    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...