National Library of Energy BETA

Sample records for antifungal drug molecules

  1. Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Wednesday, 24 February 2010 00:00 Humankind has benefitted from a long and productive relationship with yeast. For example, fermentation by yeast is an essential step in the production of bread, beer, wine, and even biofuels. However, not all yeast are beneficial. One strain of yeast, Candida albicans, grows unnoticed on most peoples' skin and in

  2. Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Humankind has benefitted from a long and productive relationship with yeast. For example, fermentation by yeast is an essential step in the production of bread, beer, wine, and even biofuels. However, not all yeast are beneficial. One strain of yeast, Candida albicans, grows unnoticed on most peoples' skin and in the intestines. In response to certain environmental conditions, C. albicans can switch to a pathogenic

  3. Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Humankind has benefitted from a long and productive relationship with yeast. For example, fermentation by yeast is an essential step in the production of bread, beer, wine, and even biofuels. However, not all yeast are beneficial. One strain of yeast, Candida albicans, grows unnoticed on most peoples' skin and in the intestines. In response to certain environmental conditions, C. albicans can switch to a pathogenic

  4. Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Humankind has benefitted from a long and productive relationship with yeast. For example, fermentation by yeast is an essential step in the production of bread, beer, wine, and even biofuels. However, not all yeast are beneficial. One strain of yeast, Candida albicans, grows unnoticed on most peoples' skin and in the intestines. In response to certain environmental conditions, C. albicans can switch to a pathogenic

  5. Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Humankind has benefitted from a long and productive relationship with yeast. For example, fermentation by yeast is an essential step in the production of bread, beer, wine, and even biofuels. However, not all yeast are beneficial. One strain of yeast, Candida albicans, grows unnoticed on most peoples' skin and in the intestines. In response to certain environmental conditions, C. albicans can switch to a pathogenic

  6. Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Humankind has benefitted from a long and productive relationship with yeast. For example, fermentation by yeast is an essential step in the production of bread, beer, wine, and even biofuels. However, not all yeast are beneficial. One strain of yeast, Candida albicans, grows unnoticed on most peoples' skin and in the intestines. In response to certain environmental conditions, C. albicans can switch to a pathogenic

  7. Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Humankind has benefitted from a long and productive relationship with yeast. For example, fermentation by yeast is an essential step in the production of bread, beer, wine, and even biofuels. However, not all yeast are beneficial. One strain of yeast, Candida albicans, grows unnoticed on most peoples' skin and in the intestines. In response to certain environmental conditions, C. albicans can switch to a pathogenic

  8. Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Humankind has benefitted from a long and productive relationship with yeast. For example, fermentation by yeast is an essential step in the production of bread, beer, wine, and even biofuels. However, not all yeast are beneficial. One strain of yeast, Candida albicans, grows unnoticed on most peoples' skin and in the intestines. In response to certain environmental conditions, C. albicans can switch to a pathogenic

  9. Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Humankind has benefitted from a long and productive relationship with yeast. For example, fermentation by yeast is an essential step in the production of bread, beer, wine, and even biofuels. However, not all yeast are beneficial. One strain of yeast, Candida albicans, grows unnoticed on most peoples' skin and in the intestines. In response to certain environmental conditions, C. albicans can switch to a pathogenic

  10. Antifungal polypeptides

    DOE Patents [OSTI]

    Altier, Daniel J.; Ellanskaya, Irina; Ellanskaya, legal representative, Natalia; Gilliam, Jacob T.; Hunter-Cevera, Jennie; Presnail, James K.; Schepers, Eric; Simmons, Carl R.; Torok, Tamas; Yalpani, Nasser

    2009-09-15

    The invention relates to antifungal compositions and methods for protecting a plant from a fungal pathogen. Compositions including antifungal polypeptides isolated from a fungal fermentation broth are provided.

  11. Imaging Antifungal Drug Molecules in Action using Soft X-Ray...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    development. Cell CAT Scans: 3-D Cell Imaging Routine medical x rays, such as chest x rays, can be used to identify a number of diseases. But this technique only produces...

  12. Molecule Nanoweaver Improves Drug Delivery and Treatment Efficacy...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    along the synthetic route by using the powerful tool of solid-state NMR analyses. Upon development of a mature protocol, the Molecule Nanoweaver would operate on an assembly...

  13. Antifungal polypeptides

    DOE Patents [OSTI]

    Altier, Daniel J.; Dahlbacka, Glen; Elleskaya, Irina; Ellanskaya, legal representative, Natalia; Herrmann, Rafael; Hunter-Cevera, Jennie; McCutchen, Billy F.; Presnail, James K.; Rice, Janet A.; Schepers, Eric; Simmons, Carl R.; Torok, Tamas; Yalpani, Nasser

    2011-04-12

    Compositions and methods for protecting a plant from a pathogen, particularly a fungal pathogen, are provided. Compositions include novel amino acid sequences, and variants and fragments thereof, for antipathogenic polypeptides that were isolated from microbial fermentation broths. Nucleic acid molecules comprising nucleotide sequences that encode the antipathogenic polypeptides of the invention are also provided. A method for inducing pathogen resistance in a plant using the nucleotide sequences disclosed herein is further provided. The method comprises introducing into a plant an expression cassette comprising a promoter operably linked to a nucleotide sequence that encodes an antipathogenic polypeptide of the invention. Compositions comprising an antipathogenic polypeptide or a transformed microorganism comprising a nucleic acid of the invention in combination with a carrier and methods of using these compositions to protect a plant from a pathogen are further provided. Transformed plants, plant cells, seeds, and microorganisms comprising a nucleotide sequence that encodes an antipathogenic polypeptide of the invention, or variant or fragment thereof, are also disclosed.

  14. Antifungal polypeptides

    DOE Patents [OSTI]

    Altier, Daniel J.; Dahlbacka, Glen; Ellanskaya, Irina; Ellanskaya, legal representative, Natalia; Herrmann, Rafael; Hunter-Cevera, Jennie; McCutchen, Billy F.; Presnail, James K.; Rice, Janet A.; Schepers, Eric; Simmons, Carl R.; Torok, Tamas; Yalpani, Nasser

    2012-04-03

    Compositions and methods for protecting a plant from a pathogen, particularly a fungal pathogen, are provided. Compositions include novel amino acid sequences, and variants and fragments thereof, for antipathogenic polypeptides that were isolated from microbial fermentation broths. Nucleic acid molecules comprising nucleotide sequences that encode the antipathogenic polypeptides of the invention are also provided. A method for inducing pathogen resistance in a plant using the nucleotide sequences disclosed herein is further provided. The method comprises introducing into a plant an expression cassette comprising a promoter operably linked to a nucleotide sequence that encodes an antipathogenic polypeptide of the invention. Compositions comprising an antipathogenic polypeptide or a transformed microorganism comprising a nucleic acid of the invention in combination with a carrier and methods of using these compositions to protect a plant from a pathogen are further provided. Transformed plants, plant cells, seeds, and microorganisms comprising a nucleotide sequence that encodes an antipathogenic polypeptide of the invention, or variant or fragment thereof, are also disclosed.

  15. Antifungal polypeptides

    DOE Patents [OSTI]

    Altier, Daniel J.; Dahlbacka, Glen; Ellanskaya, legal representative, Natalia; Herrmann, Rafael; Hunter-Cevera, Jennie; McCutchen, Billy F.; Presnail, James K.; Rice, Janet A.; Schepers, Eric; Simmons, Carl R.; Torok, Tamas; Yalpani, Nasser; Ellanskaya, deceased, Irina

    2007-12-11

    Compositions and methods for protecting a plant from a pathogen, particularly a fungal pathogen, are provided. Compositions include novel amino acid sequences, and variants and fragments thereof, for antipathogenic polypeptides that were isolated from microbial fermentation broths. Nucleic acid molecules comprising nucleotide sequences that encode the antipathogenic polypeptides of the invention are also provided. A method for inducing pathogen resistance in a plant using the nucleotide sequences disclosed herein is further provided. The method comprises introducing into a plant an expression cassette comprising a promoter operably linked to a nucleotide sequence that encodes an antipathogenic polypeptide of the invention. Compositions comprising an antipathogenic polypeptide or a transformed microorganism comprising a nucleic acid of the invention in combination with a carrier and methods of using these compositions to protect a plant from a pathogen are further provided. Transformed plants, plant cells, seeds, and microorganisms comprising a nucleotide sequence that encodes an antipathogenic polypeptide of the invention, or variant or fragment thereof, are also disclosed.

  16. Antifungal polypeptides

    DOE Patents [OSTI]

    Altier, Daniel J.; Dahlbacka, Glen; Elleskaya, Irina; Ellanskaya, legal representative; Natalia; Herrmann, Rafael; Hunter-Cevera, Jennie; McCutchen, Billy F.; Presnail, James K.; Rice, Janet A.; Schepers, Eric; Simmons, Carl R.; Torok, Tamas; Yalpani, Nasser

    2010-08-10

    Compositions and methods for protecting a plant from a pathogen, particularly a fungal pathogen, are provided. Compositions include novel amino acid sequences, and variants and fragments thereof, for antipathogenic polypeptides that were isolated from microbial fermentation broths. Nucleic acid molecules comprising nucleotide sequences that encode the antipathogenic polypeptides of the invention are also provided. A method for inducing pathogen resistance in a plant using the nucleotide sequences disclosed herein is further provided. The method comprises introducing into a plant an expression cassette comprising a promoter operably linked to a nucleotide sequence that encodes an antipathogenic polypeptide of the invention. Compositions comprising an antipathogenic polypeptide or a transformed microorganism comprising a nucleic acid of the invention in combination with a carrier and methods of using these compositions to protect a plant from a pathogen are further provided. Transformed plants, plant cells, seeds, and microorganisms comprising a nucleotide sequence that encodes an antipathogenic polypeptide of the invention, or variant or fragment thereof, are also disclosed.

  17. Molecule nanoweaver

    DOE Patents [OSTI]

    Gerald, II; Rex E.; Klingler, Robert J.; Rathke, Jerome W.; Diaz, Rocio; Vukovic, Lela

    2009-03-10

    A method, apparatus, and system for constructing uniform macroscopic films with tailored geometric assemblies of molecules on the nanometer scale. The method, apparatus, and system include providing starting molecules of selected character, applying one or more force fields to the molecules to cause them to order and condense with NMR spectra and images being used to monitor progress in creating the desired geometrical assembly and functionality of molecules that comprise the films.

  18. NERSC Helps Physicists ID New Molecules With Unique Features

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    applications," they wrote. "These molecules can be used for targeted non-invasive drug delivery. When assembled, the molecules can also form new high strength magnets...

  19. X-ray characterization of solid small molecule organic materials

    DOE Patents [OSTI]

    Billinge, Simon; Shankland, Kenneth; Shankland, Norman; Florence, Alastair

    2014-06-10

    The present invention provides, inter alia, methods of characterizing a small molecule organic material, e.g., a drug or a drug product. This method includes subjecting the solid small molecule organic material to x-ray total scattering analysis at a short wavelength, collecting data generated thereby, and mathematically transforming the data to provide a refined set of data.

  20. Prescription Drugs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Prescription Drugs Prescription Drugs Prescription drug benefits are determined by your medical plan. Contact Prime Therapeutics Prescription drug coverage for retirees Your Blue...

  1. NERSC Helps Physicists ID New Molecules With Unique Features

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    NERSC Helps Physicists ID New Molecules With Unique Features NERSC Helps Physicists ID New Molecules With Unique Features Hollow magnetic cage molecules may have applications in technology, healthcare August 10, 2013 NERSC supercomputing resources helped Virginia Commonwealth University (VCU) researchers determine it may be possible to create large, hollow magnetic cage molecules that could be used in medicine as a drug delivery system to noninvasively treat tumors and in other emerging

  2. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule...

  3. Antifungal activity of gold nanoparticles prepared by solvothermal method

    SciTech Connect (OSTI)

    Ahmad, Tokeer; Wani, Irshad A.; Lone, Irfan H.; Ganguly, Aparna; Manzoor, Nikhat; Ahmad, Aijaz; Ahmed, Jahangeer; Al-Shihri, Ayed S.

    2013-01-15

    Graphical abstract: Gold nanoparticles (7 and 15 nm) of very high surface area (329 and 269 m{sup 2}/g) have been successfully synthesized through solvothermal method by using tin chloride and sodium borohydride as reducing agents. As-prepared gold nanoparticles shows very excellent antifungal activity against Candida isolates and activity increases with decrease in the particle size. Display Omitted Highlights: ► Effect of reducing agents on the morphology of gold nanoparticles. ► Highly uniform and monodisperse gold nanoparticles (7 nm). ► Highest surface area of gold nanoparticles (329 m{sup 2/}g). ► Excellent antifungal activity of gold nanoparticles against Candida strains. -- Abstract: Gold nanoparticles have been successfully synthesized by solvothermal method using SnCl{sub 2} and NaBH{sub 4} as reducing agents. X-ray diffraction studies show highly crystalline and monophasic nature of the gold nanoparticles with face centred cubic structure. The transmission electron microscopic studies show the formation of nearly spherical gold nanoparticles of average size of 15 nm using SnCl{sub 2}, however, NaBH{sub 4} produced highly uniform, monodispersed and spherical gold nanoparticles of average grain size of 7 nm. A high surface area of 329 m{sup 2}/g for 7 nm and 269 m{sup 2}/g for 15 nm gold nanoparticles was observed. UV–vis studies assert the excitations over the visible region due to transverse and longitudinal surface plasmon modes. The gold nanoparticles exhibit excellent size dependant antifungal activity and greater biocidal action against Candida isolates for 7 nm sized gold nanoparticles restricting the transmembrane H{sup +} efflux of the Candida species than 15 nm sized gold nanoparticles.

  4. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cool Magnetic Molecules Cool Magnetic Molecules Print Wednesday, 25 May 2011 00:00 Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost

  5. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability

  6. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability

  7. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability

  8. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability

  9. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability

  10. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability

  11. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability

  12. Roaming Molecule Dynamics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Roaming Molecule Dynamics - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management Programs Advanced

  13. Smarter Drugs: How Protein Crystallography Revolutionizes Drug Design

    SciTech Connect (OSTI)

    Smith, Clyde

    2005-04-26

    According to Smith, protein crystallography allows scientists to design drugs in a much more efficient way than the standard methods traditionally used by large drug companies, which can cost close to a billion dollars and take 10 to 15 years. 'A lot of the work can be compressed down,' Smith said. Protein crystallography enables researchers to learn the structure of molecules involved in disease and health. Seeing the loops, folds and placement of atoms in anything from a virus to a healthy cell membrane gives important information about how these things work - and how to encourage, sidestep or stop their functions. Drug design can be much faster when the relationship between structure and function tells you what area of a molecule to target. Smith will use a timeline to illustrate the traditional methods of drug development and the new ways it can be done now. 'It is very exciting work. There have been some failures, but many successes too.' A new drug to combat the flu was developed in a year or so. Smith will tell us how. He will also highlight drugs developed to combat HIV, Tuberculosis, hypertension and Anthrax.

  14. Protein-Based Nanomedicine Platforms for Drug Delivery

    SciTech Connect (OSTI)

    Ma Ham, Aihui; Tang, Zhiwen; Wu, Hong; Wang, Jun; Lin, Yuehe

    2009-08-03

    Drug delivery systems have been developed for many years, however some limitations still hurdle the pace of going to clinical phase, for example, poor biodistribution, drug molecule cytotoxicity, tissue damage, quick clearance from the circulation system, solubility and stability of drug molecules. To overcome the limitations of drug delivery, biomaterials have to be developed and applied to drug delivery to protect the drug molecules and to enhance the drugs efficacy. Protein-based nanomedicine platforms for drug delivery are platforms comprised of naturally self-assembled protein subunits of the same protein or a combination of proteins making up a complete system. They are ideal for drug delivery platforms due to their biocompatibility and biodegradability coupled with low toxicity. A variety of proteins have been used and characterized for drug delivery systems including the ferritin/apoferritin protein cage, plant derived viral capsids, the small Heat shock protein (sHsp) cage, albumin, soy and whey protein, collagen, and gelatin. There are many different types and shapes that have been prepared to deliver drug molecules using protein-based platforms including the various protein cages, microspheres, nanoparticles, hydrogels, films, minirods and minipellets. There are over 30 therapeutic compounds that have been investigated with protein-based drug delivery platforms for the potential treatment of various cancers, infectious diseases, chronic diseases, autoimmune diseases. In protein-based drug delivery platforms, protein cage is the most newly developed biomaterials for drug delivery and therapeutic applications. Their uniform sizes, multifunctions, and biodegradability push them to the frontier for drug delivery. In this review, the recent strategic development of drug delivery has been discussed with a special emphasis upon the polymer based, especially protein-based nanomedicine platforms for drug delivery. The advantages and disadvantages are also

  15. Geranyl diphosphate synthase molecules, and nucleic acid molecules encoding same

    DOE Patents [OSTI]

    Croteau, Rodney Bruce; Burke, Charles Cullen

    2008-06-24

    In one aspect, the present invention provides isolated nucleic acid molecules that each encode a geranyl diphosphate synthase protein, wherein each isolated nucleic acid molecule hybridizes to a nucleic acid molecule consisting of the sequence set forth in SEQ ID NO:1 under conditions of 5.times.SSC at 45.degree. C. for one hour. The present invention also provides isolated geranyl diphosphate synthase proteins, and methods for altering the level of expression of geranyl diphosphate synthase protein in a host cell.

  16. Electrochromic Graphene Molecules

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ji, Zhiqiang; Doorn, Stephen K.; Sykora, Milan

    2015-03-13

    Polyclic aromatic hydrocarbons, also called Graphene Molecules (GMs), with chemical composition C132H36(COOH)2 were synthesized in-situ on the surface of transparent nanocrystaline indium tin oxide (nc-ITO) electrodes. Their electronic structure was studied electrochemically and spectro-electrochemically. Variations in the potential applied onto the nc-ITO/GM electrodes induce only small changes in the observed current but they produce dramatic changes in the absorption of the GMs, which are associated with their oxidation and reduction. Analysis of the absorption changes using modified Nernst equation is used to determine standard potentials associated with the individual charge transfer processes. For the GMs prepared here these were foundmore » to be E1,ox 0 = 0.77± 0.01 V and E2,ox 0 = 1.24 ± 0.02 V vs. NHE for the first and second oxidation and E1,red 0 = -1.50 ± 0.04 V for the first reduction. The charge transfer processes are found to be non-ideal. The non-ideality factors associated with the oxidation and reduction processes suggest presence of strong interactions between the GM redox centers. Under the conditions of potential cycling GMs show rapid (seconds) color change with high contrast and stability. An electrochromic application is demonstrated wherein the GMs are used as the optically active component.« less

  17. Single molecule tracking

    DOE Patents [OSTI]

    Shera, E.B.

    1987-10-07

    A detection system is provided for identifying individual particles or molecules having characteristic emission in a flow train of the particles in a flow cell. A position sensitive sensor is located adjacent the flow cell in a position effective to detect the emissions from the particles within the flow cell and to assign spatial and temporal coordinates for the detected emissions. A computer is then enabled to predict spatial and temporal coordinates for the particle in the flow train as a function of a first detected emission. Comparison hardware or software then compares subsequent detected spatial and temporal coordinates with the predicted spatial and temporal coordinates to determine whether subsequently detected emissions originate from a particle in the train of particles. In one embodiment, the particles include fluorescent dyes which are excited to fluoresce a spectrum characteristic of the particular particle. Photons are emitted adjacent at least one microchannel plate sensor to enable spatial and temporal coordinates to be assigned. The effect of comparing detected coordinates with predicted coordinates is to define a moving sample volume which effectively precludes the effects of background emissions. 3 figs.

  18. Single molecule tracking

    DOE Patents [OSTI]

    Shera, E. Brooks

    1988-01-01

    A detection system is provided for identifying individual particles or molecules having characteristic emission in a flow train of the particles in a flow cell. A position sensitive sensor is located adjacent the flow cell in a position effective to detect the emissions from the particles within the flow cell and to assign spatial and temporal coordinates for the detected emissions. A computer is then enabled to predict spatial and temporal coordinates for the particle in the flow train as a function of a first detected emission. Comparison hardware or software then compares subsequent detected spatial and temporal coordinates with the predicted spatial and temporal coordinates to determine whether subsequently detected emissions originate from a particle in the train of particles. In one embodiment, the particles include fluorescent dyes which are excited to fluoresce a spectrum characteristic of the particular particle. Photones are emitted adjacent at least one microchannel plate sensor to enable spatial and temporal coordinates to be assigned. The effect of comparing detected coordinates with predicted coordinates is to define a moving sample volume which effectively precludes the effects of background emissions.

  19. Electrochromic Graphene Molecules

    SciTech Connect (OSTI)

    Ji, Zhiqiang; Doorn, Stephen K.; Sykora, Milan

    2015-03-13

    Polyclic aromatic hydrocarbons, also called Graphene Molecules (GMs), with chemical composition C132H36(COOH)2 were synthesized in-situ on the surface of transparent nanocrystaline indium tin oxide (nc-ITO) electrodes. Their electronic structure was studied electrochemically and spectro-electrochemically. Variations in the potential applied onto the nc-ITO/GM electrodes induce only small changes in the observed current but they produce dramatic changes in the absorption of the GMs, which are associated with their oxidation and reduction. Analysis of the absorption changes using modified Nernst equation is used to determine standard potentials associated with the individual charge transfer processes. For the GMs prepared here these were found to be E1,ox 0 = 0.77 0.01 V and E2,ox 0 = 1.24 0.02 V vs. NHE for the first and second oxidation and E1,red 0 = -1.50 0.04 V for the first reduction. The charge transfer processes are found to be non-ideal. The non-ideality factors associated with the oxidation and reduction processes suggest presence of strong interactions between the GM redox centers. Under the conditions of potential cycling GMs show rapid (seconds) color change with high contrast and stability. An electrochromic application is demonstrated wherein the GMs are used as the optically active component.

  20. Nucleic acids encoding antifungal polypeptides and uses thereof

    DOE Patents [OSTI]

    Altier, Daniel J.; Ellanskaya, I. A.; Gilliam, Jacob T.; Hunter-Cevera, Jennie; Presnail, James K; Schepers, Eric; Simmons, Carl R.; Torok, Tamas; Yalpani, Nasser

    2010-11-02

    Compositions and methods for protecting a plant from a pathogen, particularly a fungal pathogen, are provided. Compositions include an amino acid sequence, and variants and fragments thereof, for an antipathogenic polypeptide that was isolated from a fungal fermentation broth. Nucleic acid molecules that encode the antipathogenic polypeptides of the invention, and antipathogenic domains thereof, are also provided. A method for inducing pathogen resistance in a plant using the nucleotide sequences disclosed herein is further provided. The method comprises introducing into a plant an expression cassette comprising a promoter operably linked to a nucleotide sequence that encodes an antipathogenic polypeptide of the invention. Compositions comprising an antipathogenic polypeptide or a transformed microorganism comprising a nucleic acid of the invention in combination with a carrier and methods of using these compositions to protect a plant from a pathogen are further provided. Transformed plants, plant cells, seeds, and microorganisms comprising a nucleotide sequence that encodes an antipathogenic polypeptide of the invention are also disclosed.

  1. Aromatic molecules as spintronic devices

    SciTech Connect (OSTI)

    Ojeda, J. H.; Orellana, P. A.; Laroze, D.

    2014-03-14

    In this paper, we study the spin-dependent electron transport through aromatic molecular chains attached to two semi-infinite leads. We model this system taking into account different geometrical configurations which are all characterized by a tight binding Hamiltonian. Based on the Green's function approach with a Landauer formalism, we find spin-dependent transport in short aromatic molecules by applying external magnetic fields. Additionally, we find that the magnetoresistance of aromatic molecules can reach different values, which are dependent on the variations in the applied magnetic field, length of the molecules, and the interactions between the contacts and the aromatic molecule.

  2. Electrochromic Graphene Molecules

    SciTech Connect (OSTI)

    Ji, Zhiqiang; Doorn, Stephen K.; Sykora, Milan

    2015-03-13

    Polyclic aromatic hydrocarbons, also called Graphene Molecules (GMs), with chemical composition C132H36(COOH)2 were synthesized in-situ on the surface of transparent nanocrystaline indium tin oxide (nc-ITO) electrodes. Their electronic structure was studied electrochemically and spectro-electrochemically. Variations in the potential applied onto the nc-ITO/GM electrodes induce only small changes in the observed current but they produce dramatic changes in the absorption of the GMs, which are associated with their oxidation and reduction. Analysis of the absorption changes using modified Nernst equation is used to determine standard potentials associated with the individual charge transfer processes. For the GMs prepared here these were found to be E1,ox 0 = 0.77± 0.01 V and E2,ox 0 = 1.24 ± 0.02 V vs. NHE for the first and second oxidation and E1,red 0 = -1.50 ± 0.04 V for the first reduction. The charge transfer processes are found to be non-ideal. The non-ideality factors associated with the oxidation and reduction processes suggest presence of strong interactions between the GM redox centers. Under the conditions of potential cycling GMs show rapid (seconds) color change with high contrast and stability. An electrochromic application is demonstrated wherein the GMs are used as the optically active component.

  3. Interaction between hydrogen molecules and metallofullerenes...

    Office of Scientific and Technical Information (OSTI)

    Interaction between hydrogen molecules and metallofullerenes. Citation Details In-Document Search Title: Interaction between hydrogen molecules and metallofullerenes. Within ...

  4. Science@SLAC—Discovering New Drugs

    SciTech Connect (OSTI)

    Drell, Persis; Smith, Clyde; Bushnell, Dave

    2011-10-18

    SLAC scientists and private-sector drug makers describe how a public--private partnership combined with the specialized X-rays from the Stanford Synchrotron Radiation Lightsource (SSRL) enable smart drug design that eliminates the costly trial-and-error approach used by traditional drug companies. SSRL is a synchrotron lightsource laboratory used by scientists from a range of disciplines to study matter on the scale of atoms and molecules. Featured in this video are SLAC Laboratory Director Persis Drell, SSRL staff scientist Clyde Smith, and Dave Bushnell, a scientist from startup drug maker Cocrystal Discovery Inc.

  5. Quantum transport through aromatic molecules

    SciTech Connect (OSTI)

    Ojeda, J. H.; Rey-Gonzlez, R. R.; Laroze, D.

    2013-12-07

    In this paper, we study the electronic transport properties through aromatic molecules connected to two semi-infinite leads. The molecules are in different geometrical configurations including arrays. Using a nearest neighbor tight-binding approach, the transport properties are analyzed into a Green's function technique within a real-space renormalization scheme. We calculate the transmission probability and the Current-Voltage characteristics as a function of a molecule-leads coupling parameter. Our results show different transport regimes for these systems, exhibiting metal-semiconductor-insulator transitions and the possibility to employ them in molecular devices.

  6. Antifungal polypeptides

    SciTech Connect (OSTI)

    Altier, Daniel J.; Crane, Virginia C.; Ellanskaya, Irina; Ellanskaya, legal representative, Natalia; Gilliam, Jacob T.; Hunter-Cevera, Jennie; Presnail, James K.; Schepers, Eric J.; Simmons, Carl R.; Torok, Tamas; Yalpani, Nasser

    2009-10-06

    The invention relates to compositions including amino acid sequences isolated from fungal fermentation broths and methods for protecting a plant from a pathogen, particularly a fungal pathogen.

  7. A New Way to Display the 3-D Structure of Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A New Way to Display the 3-D Structure of Molecules Researchers have created a sort of nanoscale display case that enables new atomic-scale views of hard-to-study chemical and biological samples. Their work could help to reveal new structural details for a range of challenging molecules, such as complex chemical compounds and potentially new drugs, by stabilizing them inside metal-organic frameworks (MOFs).

  8. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    cell. The class of dye molecules used in this research is related to the dye that gives blue jeans their color. By choosing organic molecules, an enormous repertoire of possible...

  9. Drug Retention Times

    SciTech Connect (OSTI)

    Center for Human Reliability Studies

    2007-05-01

    The purpose of this monograph is to provide information on drug retention times in the human body. The information provided is based on plausible illegal drug use activities that might be engaged in by a recreational drug user.

  10. Ultrafast electron diffraction from aligned molecules

    SciTech Connect (OSTI)

    Centurion, Martin

    2015-08-17

    The aim of this project was to record time-resolved electron diffraction patterns of aligned molecules and to reconstruct the 3D molecular structure. The molecules are aligned non-adiabatically using a femtosecond laser pulse. A femtosecond electron pulse then records a diffraction pattern while the molecules are aligned. The diffraction patterns are then be processed to obtain the molecular structure.

  11. Electrokinetic concentration of charged molecules

    DOE Patents [OSTI]

    Singh, Anup K.; Neyer, David W.; Schoeniger, Joseph S.; Garguilo, Michael G.

    2002-01-01

    A method for separating and concentrating charged species from uncharged or neutral species regardless of size differential. The method uses reversible electric field induced retention of charged species, that can include molecules and molecular aggregates such as dimers, polymers, multimers, colloids, micelles, and liposomes, in volumes and on surfaces of porous materials. The retained charged species are subsequently quantitatively removed from the porous material by a pressure driven flow that passes through the retention volume and is independent of direction thus, a multi-directional flow field is not required. Uncharged species pass through the system unimpeded thus effecting a complete separation of charged and uncharged species and making possible concentration factors greater than 1000-fold.

  12. Multifunctional hyper-structured molecules

    SciTech Connect (OSTI)

    Wada, T.; Zhang, Y.; Aoyama, T.; Kubo, Y.; Sasabe, H.

    1998-07-01

    To fill the gap between molecular design and the architecture of three-dimensional functional structures, the authors propose novel hyper-structured molecules (HSMs) based on well-defined and topologically controlled molecular systems. To this end they have developed carbazole dendrimers, trimers, cyclic oligomers and chromogenic calix[4]arenes as HSMs. Photorefractivity was selected as the primary target function of these HSMs. Oligomers developed in their laboratory exhibit intrinsic photocarrier generation, transport, electro-optic, film-forming and poling properties. These multifunctional properties allow us to demonstrate optical image processing using optical phase conjugation. The topological shapes of indoaniline-derived calix[4]arenes were studied by hyper-Rayleigh scattering. The two indoaniline moieties in calix[4]arene derivatives were pre-aligned so as to enhance the net molecular hyperpolarizability. Besides dendric oligomers, cyclic oligomers can be used as a molecular platform which allows molecular level tuning of shape, size and topology for superior opto-electronic functions.

  13. Electrorheological crystallization of proteins and other molecules

    DOE Patents [OSTI]

    Craig, G.D.; Rupp, B.

    1996-06-11

    An electrorheological crystalline mass of a molecule is formed by dispersing the molecule in a dispersion fluid and subjecting the molecule dispersion to a uniform electrical field for a period of time during which time an electrorheological crystalline mass is formed. Molecules that may be used to form an electrorheological crystalline mass include any organic or inorganic molecule which has a permanent dipole and/or which is capable of becoming an induced dipole in the presence of an electric field. The molecules used to form the electrorheological crystalline mass are preferably macromolecules, such as biomolecules, such as proteins, nucleic acids, carbohydrates, lipoproteins and viruses. Molecules are crystallized by a method in which an electric field is maintained for a period of time after the electrorheological crystalline mass has formed during which time at least some of the molecules making up the electrorheological crystalline mass form a crystal lattice. The three dimensional structure of a molecule is determined by a method in which an electrorheological crystalline mass of the molecule is formed, an X-ray diffraction pattern of the electrorheological crystalline mass is obtained and the three dimensional structure of the molecule is calculated from the X-ray diffraction pattern. 4 figs.

  14. Electrorheological crystallization of proteins and other molecules

    DOE Patents [OSTI]

    Craig, George D.; Rupp, Bernhard

    1996-01-01

    An electrorheological crystalline mass of a molecule is formed by dispersing the molecule in a dispersion fluid and subjecting the molecule dispersion to a uniform electrical field for a period of time during which time an electrorheological crystalline mass is formed. Molecules that may be used to form an electrorheological crystalline mass include any organic or inorganic molecule which has a permanent dipole and/or which is capable of becoming an induced dipole in the presence of an electric field. The molecules used to form the electrorheological crystalline mass are preferably macromolecules, such as biomolecules, such as proteins, nucleic acids, carbohydrates, lipoproteins and viruses. Molecules are crystallized by a method in which an electric field is maintained for a period of time after the electrorheological crystalline mass has formed during which time at least some of the molecules making up the electrorheological crystalline mass form a crystal lattice. The three dimensional structure of a molecule is determined by a method in which an electrorheological crystalline mass of the molecule is formed, an x-ray diffraction pattern of the electrorheological crystalline mass is obtained and the three dimensional structure of the molecule is calculated from the x-ray diffraction pattern.

  15. Covalent Bonding in Actinide Sandwich Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    improvements in organometallic catalysts that are employed across industry for the polymerization of organic molecules. In this study, Minasian et al. quantitatively probe...

  16. Production and Trapping of Ultracold Polar Molecules

    SciTech Connect (OSTI)

    David, DeMille

    2015-04-21

    We report a set of experiments aimed at the production and trapping of ultracold polar molecules. We begin with samples of laser-cooled and trapped Rb and Cs atoms, and bind them together to form polar RbCs molecules. The binding is accomplished via photoassociation, which uses a laser to catalyze the sticking process. We report results from investigation of a new pathway for photoassociation that can produce molecules in their absolute ground state of vibrational and rotational motion. We also report preliminary observations of collisions between these ground-state molecules and co-trapped atoms.

  17. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell...

  18. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption....

  19. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Organic molecules in dye-sensitized solar cells exhibit great potential to increase the efficiency and reduce the cost of photovoltaic power generation by allowing a wide variety ...

  20. Covalent Bonding in Actinide Sandwich Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    rows) mix with orbitals of carbon in various configurations has been the subject of debate. Development of more precise models of the electronic structure in molecules with...

  1. Inverted, semitransparent small molecule photovoltaic cells ...

    Office of Scientific and Technical Information (OSTI)

    small molecule photovoltaic cells Authors: Xiao, Xin 1 ; Lee, Kyusang 1 ; Forrest, Stephen R. 2 + Show Author Affiliations Department of Electrical Engineering and Computer...

  2. Tumor suppressor molecules and methods of use

    DOE Patents [OSTI]

    Welch, Peter J.; Barber, Jack R.

    2004-09-07

    The invention provides substantially pure tumor suppressor nucleic acid molecules and tumor suppressor polypeptides. The invention also provides hairpin ribozymes and antibodies selective for these tumor suppressor molecules. Also provided are methods of detecting a neoplastic cell in a sample using detectable agents specific for the tumor suppressor nucleic acids and polypeptides.

  3. Pharmacokinetic drivers of toxicity for basic molecules: Strategy to lower pKa results in decreased tissue exposure and toxicity for a small molecule Met inhibitor

    SciTech Connect (OSTI)

    Diaz, Dolores; Ford, Kevin A.; Hartley, Dylan P.; Harstad, Eric B.; Cain, Gary R.; Achilles-Poon, Kirsten; Nguyen, Trung; Peng, Jing; Zheng, Zhong; Merchant, Mark; Sutherlin, Daniel P.; Gaudino, John J.; Kaus, Robert; Lewin-Koh, Sock C.; Choo, Edna F.; Liederer, Bianca M.; Dambach, Donna M.

    2013-01-01

    Several toxicities are clearly driven by free drug concentrations in plasma, such as toxicities related to on-target exaggerated pharmacology or off-target pharmacological activity associated with receptors, enzymes or ion channels. However, there are examples in which organ toxicities appear to correlate better with total drug concentrations in the target tissues, rather than with free drug concentrations in plasma. Here we present a case study in which a small molecule Met inhibitor, GEN-203, with significant liver and bone marrow toxicity in preclinical species was modified with the intention of increasing the safety margin. GEN-203 is a lipophilic weak base as demonstrated by its physicochemical and structural properties: high LogD (distribution coefficient) (4.3) and high measured pKa (7.45) due to the basic amine (N-ethyl-3-fluoro-4-aminopiperidine). The physicochemical properties of GEN-203 were hypothesized to drive the high distribution of this compound to tissues as evidenced by a moderately-high volume of distribution (Vd > 3 l/kg) in mouse and subsequent toxicities of the compound. Specifically, the basicity of GEN-203 was decreased through addition of a second fluorine in the 3-position of the aminopiperidine to yield GEN-890 (N-ethyl-3,3-difluoro-4-aminopiperidine), which decreased the volume of distribution of the compound in mouse (Vd = 1.0 l/kg), decreased its tissue drug concentrations and led to decreased toxicity in mice. This strategy suggests that when toxicity is driven by tissue drug concentrations, optimization of the physicochemical parameters that drive tissue distribution can result in decreased drug concentrations in tissues, resulting in lower toxicity and improved safety margins. -- Highlights: ? Lower pKa for a small molecule: reduced tissue drug levels and toxicity. ? New analysis tools to assess electrostatic effects and ionization are presented. ? Chemical and PK drivers of toxicity can be leveraged to improve safety.

  4. Attachment of second harmonic-active moiety to molecules for detection of molecules at interfaces

    DOE Patents [OSTI]

    Salafsky, Joshua S.; Eisenthal, Kenneth B.

    2005-10-11

    This invention provides methods of detecting molecules at an interface, which comprise labeling the molecules with a second harmonic-active moiety and detecting the labeled molecules at the interface using a surface selective technique. The invention also provides methods for detecting a molecule in a medium and for determining the orientation of a molecular species within a planar surface using a second harmonic-active moiety and a surface selective technique.

  5. Chiral Isotropic Liquids from Achiral Molecules

    SciTech Connect (OSTI)

    L Hough; M Spannuth; M Nakata; D Coleman; C Jones; G Dantlgraber; C Tschierske; J Watanabe; N Clark; et al.

    2011-12-31

    A variety of simple bent-core molecules exhibit smectic liquid crystal phases of planar fluid layers that are spontaneously both polar and chiral in the absence of crystalline order. We found that because of intralayer structural mismatch, such layers are also only marginally stable against spontaneous saddle splay deformation, which is incompatible with long-range order. This results in macroscopically isotropic fluids that possess only short-range orientational and positional order, in which the only macroscopically broken symmetry is chirality - even though the phases are formed from achiral molecules. Their conglomerate domains exhibit optical rotatory powers comparable to the highest ever found for isotropic fluids of chiral molecules.

  6. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The most cost-effective solar cells are not high-end, high-efficiency single-crystal devices, but rather low-end cells based on organic molecules or conducting polymers. Vital ...

  7. Do triatomic molecules echo atomic periodicity?

    SciTech Connect (OSTI)

    Hefferlin, R. Barrow, J.

    2015-03-30

    Demonstrations of periodicity among triatomic-molecular spectroscopic constants underscore the role of the periodic law as a foundation of chemistry. The objective of this work is to prepare for another test using vibration frequencies ?{sub 1} of free, ground-state, main-group triatomic molecules. Using data from four data bases and from computation, we have collected ?{sub 1} data for molecules formed from second period atoms.

  8. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Biomimetic Dye Molecules for Solar Cells Print Wednesday, 28 April 2010 00:00 Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most

  9. Recovery of tritium from tritiated molecules

    DOE Patents [OSTI]

    Swansiger, W.A.

    1984-10-17

    This invention relates to the recovery of tritium from various tritiated molecules by reaction with uranium. More particularly, the invention relates to the recovery of tritium from tritiated molecules by reaction with uranium wherein the reaction is conducted in a reactor which permits the reaction to occur as a moving front reaction from the point where the tritium enters the reactor charged with uranium down the reactor until the uranium is exhausted.

  10. Covalent Bonding in Actinide Sandwich Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Covalent Bonding in Actinide Sandwich Molecules Covalent Bonding in Actinide Sandwich Molecules Print Wednesday, 28 May 2014 00:00 Glenn Seaborg was one of the first scientists to recognize that differences in the degree of covalent bonding in lanthanide and actinide compounds could have profound consequences for their unique chemical reactivity and physical properties. Now, researchers working at ALS Beamline 11.0.2 have found evidence for unexpected bonding interactions in two organometallic

  11. Sol-gel method for encapsulating molecules

    DOE Patents [OSTI]

    Brinker, C. Jeffrey; Ashley, Carol S.; Bhatia, Rimple; Singh, Anup K.

    2002-01-01

    A method for encapsulating organic molecules, and in particular, biomolecules using sol-gel chemistry. A silica sol is prepared from an aqueous alkali metal silicate solution, such as a mixture of silicon dioxide and sodium or potassium oxide in water. The pH is adjusted to a suitably low value to stabilize the sol by minimizing the rate of siloxane condensation, thereby allowing storage stability of the sol prior to gelation. The organic molecules, generally in solution, is then added with the organic molecules being encapsulated in the sol matrix. After aging, either a thin film can be prepared or a gel can be formed with the encapsulated molecules. Depending upon the acid used, pH, and other processing conditions, the gelation time can be from one minute up to several days. In the method of the present invention, no alcohols are generated as by-products during the sol-gel and encapsulation steps. The organic molecules can be added at any desired pH value, where the pH value is generally chosen to achieve the desired reactivity of the organic molecules. The method of the present invention thereby presents a sufficiently mild encapsulation method to retain a significant portion of the activity of the biomolecules, compared with the activity of the biomolecules in free solution.

  12. Structure Based Drug Design for HIM Protease: From Molecular Modeling to Cheminformatics

    SciTech Connect (OSTI)

    Volarath, Patra; Weber, Irene T.; Harrison, Robert W.

    2008-06-06

    Significant progress over the past decade in virtual representations of molecules and their physicochemical properties has produced new drugs from virtual screening of the structures of single protein molecules by conventional modeling methods. The development of clinical antiviral drugs from structural data for HIV protease has been a major success in structure based drug design. Techniques for virtual screening involve the ranking of the affinity of potential ligands for the target site on a protein. Two main alternatives have been developed: modeling of the target protein with a series of related ligand molecules, and docking molecules from a database to the target protein site. The computational speed and prediction accuracy will depend on the representation of the molecular structure and chemistry, the search or simulation algorithm, and the scoring function to rank the ligands. Moreover, the general challenges in modern computational drug design arise from the profusion of data, including whole genomes of DNA, protein structures, chemical libraries, affinity and pharmacological data. Therefore, software tools are being developed to manage and integrate diverse data, and extract and visualize meaningful relationships. Current areas of research include the development of searchable chemical databases, which requires new algorithms to represent molecules and search for structurally or chemically similar molecules, and the incorporation of machine learning techniques for data mining to improve the accuracy of predictions. Examples will be presented for the virtual screening of drugs that target HIV protease.

  13. A Supramolecular Complex in Small-Molecule Solar Cells based...

    Office of Scientific and Technical Information (OSTI)

    in Small-Molecule Solar Cells based on Contorted Aromatic Molecules Citation Details In-Document Search Title: A Supramolecular Complex in Small-Molecule Solar Cells based on ...

  14. Researchers use light to create rare uranium molecule

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Rare uranium molecule Researchers use light to create rare uranium molecule Uranium nitride materials show promise as advanced nuclear fuels due to their high density, high ...

  15. [alpha]E-catenin is an autoinhibited molecule that coactivates...

    Office of Scientific and Technical Information (OSTI)

    alphaE-catenin is an autoinhibited molecule that coactivates vinculin Citation Details In-Document Search Title: alphaE-catenin is an autoinhibited molecule that coactivates ...

  16. Molecule Nanoweaver Creates High-Tech Medical Patches and Multilayered...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Molecule Nanoweaver Creates High-Tech Medical Patches and Multilayered Capsules Technology available for licensing: Molecule Nanoweaver, a unique tool that can be used as both a...

  17. Understanding Small-Molecule Interactions in Metal-Organic Frameworks...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Understanding Small-Molecule Interactions in Metal-Organic Frameworks: Coupling Experiment ... guest molecules and the internal surface of the framework must first be understood. ...

  18. Adsorption of Organic Molecules May Explain Growth of Newly Nucleated...

    Office of Scientific and Technical Information (OSTI)

    Adsorption of Organic Molecules May Explain Growth of Newly Nucleated Clusters and New Particle Formation Citation Details In-Document Search Title: Adsorption of Organic Molecules ...

  19. Reliable Energy Level Alignment at Physisorbed Molecule-Metal...

    Office of Scientific and Technical Information (OSTI)

    at Physisorbed Molecule-Metal Interfaces from Density Functional Theory Title: Reliable Energy Level Alignment at Physisorbed Molecule-Metal Interfaces from Density Functional ...

  20. Adsorption of tris(8-hydroxyquinoline)aluminum molecules on cobalt...

    Office of Scientific and Technical Information (OSTI)

    Adsorption of tris(8-hydroxyquinoline)aluminum molecules on cobalt surfaces Prev Next Title: Adsorption of tris(8-hydroxyquinoline)aluminum molecules on cobalt surfaces ...

  1. Protein Scaffolding for Small Molecule Catalysts

    SciTech Connect (OSTI)

    Baker, David

    2014-09-14

    We aim to design hybrid catalysts for energy production and storage that combine the high specificity, affinity, and tunability of proteins with the potent chemical reactivities of small organometallic molecules. The widely used Rosetta and RosettaDesign methodologies will be extended to model novel protein / small molecule catalysts in which one or many small molecule active centers are supported and coordinated by protein scaffolding. The promise of such hybrid molecular systems will be demonstrated with the nickel-phosphine hydrogenase of DuBois et. al.We will enhance the hydrogenase activity of the catalyst by designing protein scaffolds that incorporate proton relays and systematically modulate the local environment of the catalyticcenter. In collaboration with DuBois and Shaw, the designs will be experimentally synthesized and characterized.

  2. Cavity sideband cooling of trapped molecules

    SciTech Connect (OSTI)

    Kowalewski, Markus; Vivie-Riedle, Regina de [Department of Chemistry, Ludwig-Maximilian-Universitaet, D-81377 Munich (Germany); Morigi, Giovanna [Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Theoretische Physik, Universitaet des Saarlandes, D-66041 Saarbruecken (Germany); Pinkse, Pepijn W. H. [MESA Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500AE Enschede (Netherlands)

    2011-09-15

    The efficiency of cavity sideband cooling of trapped molecules is theoretically investigated for the case in which the infrared transition between two rovibrational states is used as a cycling transition. The molecules are assumed to be trapped either by a radiofrequency or optical trapping potential, depending on whether they are charged or neutral, and confined inside a high-finesse optical resonator that enhances radiative emission into the cavity mode. Using realistic experimental parameters and COS as a representative molecular example, we show that in this setup, cooling to the trap ground state is feasible.

  3. Discovery of Small Molecules that Inhibit the Disordered Protein, p27Kip1

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Iconaru, Luigi I.; Ban, David; Bharatham, Kavitha; Ramanathan, Arvind; Zhang, Weixing; Shelat, Anang A.; Zuo, Jian; Kriwacki, Richard W.

    2015-10-28

    In disordered proteins we see that they are highly prevalent in biological systems. They control myriad signaling and regulatory processes, and their levels and/or cellular localization are often altered in human disease. In contrast to folded proteins, disordered proteins, due to conformational heterogeneity and dynamics, are not considered viable drug targets. We challenged this paradigm by identifying through NMR-based screening small molecules that bound specifically, albeit weakly, to the disordered cell cycle regulator, p27Kip1 (p27). Moreover, two groups of molecules bound to sites created by transient clusters of aromatic residues within p27. Conserved chemical features within these two groups ofmore » small molecules exhibited complementarity to their binding sites within p27, establishing structure-activity relationships for small molecule: disordered protein interactions. Finally, one compound counteracted the Cdk2/cyclin A inhibitory function of p27 in vitro, providing proof-of- principle that small molecules can inhibit the function of a disordered protein (p27) through sequestration in a conformation incapable of folding and binding to a natural regulatory target (Cdk2/cyclin A).« less

  4. Method for sequencing nucleic acid molecules

    DOE Patents [OSTI]

    Korlach, Jonas; Webb, Watt W.; Levene, Michael; Turner, Stephen; Craighead, Harold G.; Foquet, Mathieu

    2006-06-06

    The present invention is directed to a method of sequencing a target nucleic acid molecule having a plurality of bases. In its principle, the temporal order of base additions during the polymerization reaction is measured on a molecule of nucleic acid, i.e. the activity of a nucleic acid polymerizing enzyme on the template nucleic acid molecule to be sequenced is followed in real time. The sequence is deduced by identifying which base is being incorporated into the growing complementary strand of the target nucleic acid by the catalytic activity of the nucleic acid polymerizing enzyme at each step in the sequence of base additions. A polymerase on the target nucleic acid molecule complex is provided in a position suitable to move along the target nucleic acid molecule and extend the oligonucleotide primer at an active site. A plurality of labelled types of nucleotide analogs are provided proximate to the active site, with each distinguishable type of nucleotide analog being complementary to a different nucleotide in the target nucleic acid sequence. The growing nucleic acid strand is extended by using the polymerase to add a nucleotide analog to the nucleic acid strand at the active site, where the nucleotide analog being added is complementary to the nucleotide of the target nucleic acid at the active site. The nucleotide analog added to the oligonucleotide primer as a result of the polymerizing step is identified. The steps of providing labelled nucleotide analogs, polymerizing the growing nucleic acid strand, and identifying the added nucleotide analog are repeated so that the nucleic acid strand is further extended and the sequence of the target nucleic acid is determined.

  5. Method for sequencing nucleic acid molecules

    DOE Patents [OSTI]

    Korlach, Jonas; Webb, Watt W.; Levene, Michael; Turner, Stephen; Craighead, Harold G.; Foquet, Mathieu

    2006-05-30

    The present invention is directed to a method of sequencing a target nucleic acid molecule having a plurality of bases. In its principle, the temporal order of base additions during the polymerization reaction is measured on a molecule of nucleic acid, i.e. the activity of a nucleic acid polymerizing enzyme on the template nucleic acid molecule to be sequenced is followed in real time. The sequence is deduced by identifying which base is being incorporated into the growing complementary strand of the target nucleic acid by the catalytic activity of the nucleic acid polymerizing enzyme at each step in the sequence of base additions. A polymerase on the target nucleic acid molecule complex is provided in a position suitable to move along the target nucleic acid molecule and extend the oligonucleotide primer at an active site. A plurality of labelled types of nucleotide analogs are provided proximate to the active site, with each distinguishable type of nucleotide analog being complementary to a different nucleotide in the target nucleic acid sequence. The growing nucleic acid strand is extended by using the polymerase to add a nucleotide analog to the nucleic acid strand at the active site, where the nucleotide analog being added is complementary to the nucleotide of the target nucleic acid at the active site. The nucleotide analog added to the oligonucleotide primer as a result of the polymerizing step is identified. The steps of providing labelled nucleotide analogs, polymerizing the growing nucleic acid strand, and identifying the added nucleotide analog are repeated so that the nucleic acid strand is further extended and the sequence of the target nucleic acid is determined.

  6. Drug Detection Study

    Office of Scientific and Technical Information (OSTI)

    ... cause a person to be identified as using that substance in a workplace drug test. The initial test refers to the screening assay on specimens to eliminate a "negative" result ...

  7. Drug Testing Notification | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Drug Testing Notification Drug Testing Notification PDF icon Drug Testing Notification More Documents & Publications Intergrated Drug Testing System, PIA, Bechtel Jacobs C ompany, ...

  8. Automated imaging system for single molecules

    DOE Patents [OSTI]

    Schwartz, David Charles; Runnheim, Rodney; Forrest, Daniel

    2012-09-18

    There is provided a high throughput automated single molecule image collection and processing system that requires minimal initial user input. The unique features embodied in the present disclosure allow automated collection and initial processing of optical images of single molecules and their assemblies. Correct focus may be automatically maintained while images are collected. Uneven illumination in fluorescence microscopy is accounted for, and an overall robust imaging operation is provided yielding individual images prepared for further processing in external systems. Embodiments described herein are useful in studies of any macromolecules such as DNA, RNA, peptides and proteins. The automated image collection and processing system and method of same may be implemented and deployed over a computer network, and may be ergonomically optimized to facilitate user interaction.

  9. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal

  10. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal

  11. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal

  12. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal

  13. Covalent Bonding in Actinide Sandwich Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Covalent Bonding in Actinide Sandwich Molecules Print Glenn Seaborg was one of the first scientists to recognize that differences in the degree of covalent bonding in lanthanide and actinide compounds could have profound consequences for their unique chemical reactivity and physical properties. Now, researchers working at ALS Beamline 11.0.2 have found evidence for unexpected bonding interactions in two organometallic actinide "sandwich" complexes that have been lightning rods in

  14. Covalent Bonding in Actinide Sandwich Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Covalent Bonding in Actinide Sandwich Molecules Print Glenn Seaborg was one of the first scientists to recognize that differences in the degree of covalent bonding in lanthanide and actinide compounds could have profound consequences for their unique chemical reactivity and physical properties. Now, researchers working at ALS Beamline 11.0.2 have found evidence for unexpected bonding interactions in two organometallic actinide "sandwich" complexes that have been lightning rods in

  15. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal

  16. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal

  17. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal

  18. Biomimetic Dye Molecules for Solar Cells

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biomimetic Dye Molecules for Solar Cells Print Pressing energy problems provide opportunities for solid-state physicists and chemists to solve a major challenge: solar cell adoption. Though solar cells can use energy directly from the Sun to produce electricity that can be converted efficiently into other kinds of energy, they are currently too costly to compete with traditional (polluting) energy sources. The most cost-effective solar cells are not high-end, high-efficiency single-crystal

  19. Allosteric Modulation of DNA by Small Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Allosteric Modulation of DNA by Small Molecules Signals originating at the cell surface are conveyed by a complex system of interconnected signaling pathways to the nucleus. They converge at transcription factors, which in turn regulate the transcription of sets of genes that result in the gene expression. Many human diseases are caused by dysregulated gene expression and the oversupply of transcription factors may be required for the growth and metastatic behavior of human cancers. Cell

  20. Covalent Bonding in Actinide Sandwich Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Covalent Bonding in Actinide Sandwich Molecules Print Glenn Seaborg was one of the first scientists to recognize that differences in the degree of covalent bonding in lanthanide and actinide compounds could have profound consequences for their unique chemical reactivity and physical properties. Now, researchers working at ALS Beamline 11.0.2 have found evidence for unexpected bonding interactions in two organometallic actinide "sandwich" complexes that have been lightning rods in

  1. Covalent Bonding in Actinide Sandwich Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Covalent Bonding in Actinide Sandwich Molecules Print Glenn Seaborg was one of the first scientists to recognize that differences in the degree of covalent bonding in lanthanide and actinide compounds could have profound consequences for their unique chemical reactivity and physical properties. Now, researchers working at ALS Beamline 11.0.2 have found evidence for unexpected bonding interactions in two organometallic actinide "sandwich" complexes that have been lightning rods in

  2. Covalent Bonding in Actinide Sandwich Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Covalent Bonding in Actinide Sandwich Molecules Print Glenn Seaborg was one of the first scientists to recognize that differences in the degree of covalent bonding in lanthanide and actinide compounds could have profound consequences for their unique chemical reactivity and physical properties. Now, researchers working at ALS Beamline 11.0.2 have found evidence for unexpected bonding interactions in two organometallic actinide "sandwich" complexes that have been lightning rods in

  3. Covalent Bonding in Actinide Sandwich Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Covalent Bonding in Actinide Sandwich Molecules Print Glenn Seaborg was one of the first scientists to recognize that differences in the degree of covalent bonding in lanthanide and actinide compounds could have profound consequences for their unique chemical reactivity and physical properties. Now, researchers working at ALS Beamline 11.0.2 have found evidence for unexpected bonding interactions in two organometallic actinide "sandwich" complexes that have been lightning rods in

  4. Copper(II) complexes with 4-(1H-1, 2, 4-trizol-1-ylmethyl) benzoic acid: Syntheses, crystal structures and antifungal activities

    SciTech Connect (OSTI)

    Xiong, Pingping; Li, Jie; Bu, Huaiyu; Wei, Qing; Zhang, Ruolin; Chen, Sanping

    2014-07-01

    Reaction of Cu(II) with an asymmetric semi-rigid organic ligand 4-(1H-1, 2, 4-trizol-1-ylmethyl) benzoic acid (HL), yielded five compounds, [Cu{sub 0.5}L]{sub n} (1), [Cu(HL){sub 2}Cl{sub 2}]{sub n} (2), [Cu(HL){sub 2}Cl{sub 2}(H{sub 2}O)] (3), [Cu(L){sub 2}(H{sub 2}O)]{sub n} (4) and [Cu(L)(phen)(HCO{sub 2})]{sub n} (5), which have been fully characterized by infrared spectroscopy, elemental analysis, and single-crystal X-ray diffraction. As for compounds 1, 2 and 5, Cu(II) is bridged through HL, Cl{sup -}, and formic acid, respectively, featuring 1D chain-structure. In compound 3, Cu(II) with hexahedral coordination sphere is assembled through hydrogen-bonding into 3D supramolecular framework. In compound 4, 1D chain units –Cu–O–Cu–O– are ligand-bridged into a 3D network. All compounds were tested on fungi (Fusarium graminearum, Altemaria solani, Macrophoma kawatsukai, Alternaria alternata and Colletotrichum gloeosporioides). Compound 1 exhibits a better antifungal effect compared to other compounds. An effect of structure on the antifungal activity has also been correlated. - Graphical abstract: Copper(II) compounds with 4-(1H-1, 2, 4-trizol-1-ylmethyl) benzoic acid, were prepared, structurally characterized and investigated for antifungal activity. - Highlights: • The title compounds formed by thermodynamics and thermokinetics. • The five compounds show higher inhibition percentage than reactants. • The structure effect on the antifungal activity.

  5. Drug development and manufacturing

    DOE Patents [OSTI]

    Warner, Benjamin P.; McCleskey, T. Mark; Burrell, Anthony K.

    2015-10-13

    X-ray fluorescence (XRF) spectrometry has been used for detecting binding events and measuring binding selectivities between chemicals and receptors. XRF may also be used for estimating the therapeutic index of a chemical, for estimating the binding selectivity of a chemical versus chemical analogs, for measuring post-translational modifications of proteins, and for drug manufacturing.

  6. Identification of cell density signal molecule

    DOE Patents [OSTI]

    Schwarz, Richard I.

    1998-01-01

    Disclosed herein is a novel proteinaceous cell density signal molecule (CDS) between 25 and 35 kD, which is secreted by fibroblastic primary avian tendon cells in culture, and causes the cells to self-regulate their proliferation and the expression of differentiated function. It effects an increase of procollagen production in avian tendon cell cultures of ten fold while proliferation rates are decreased. CDS, and the antibodies which recognize them, are important for the development of diagnostics and treatments for injuries and diseases involving connective tissues, particularly tendon. Also disclosed are methods of production and use.

  7. Identification of cell density signal molecule

    DOE Patents [OSTI]

    Schwarz, R.I.

    1998-04-21

    Disclosed herein is a novel proteinaceous cell density signal molecule (CDS) between 25 and 35 kD, which is secreted by fibroblastic primary avian tendon cells in culture, and causes the cells to self-regulate their proliferation and the expression of differentiated function. It effects an increase of procollagen production in avian tendon cell cultures of ten fold while proliferation rates are decreased. CDS, and the antibodies which recognize them, are important for the development of diagnostics and treatments for injuries and diseases involving connective tissues, particularly tendon. Also disclosed are methods of production and use. 2 figs.

  8. Models from Big Molecules Captured in a Flash

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Models from Big Molecules Captured in a Flash Models from Big Molecules Captured in a Flash Print Sunday, 26 May 2013 00:00 The structures of most of the two million proteins in...

  9. Materials Project Releases Massive Trove of Battery and Molecule...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Materials Project Releases Massive Trove of Battery and Molecule Data Materials Project Releases Massive Trove of Battery and Molecule Data June 8, 2016 Julie Chao, JHChao@lbl.gov, ...

  10. Nanodevices for generating power from molecules and batteryless sensing

    DOE Patents [OSTI]

    Wang, Yinmin; Wang, Xianying; Hamza, Alex V.

    2014-07-15

    A nanoconverter or nanosensor is disclosed capable of directly generating electricity through physisorption interactions with molecules that are dipole containing organic species in a molecule interaction zone. High surface-to-volume ratio semiconductor nanowires or nanotubes (such as ZnO, silicon, carbon, etc.) are grown either aligned or randomly-aligned on a substrate. Epoxy or other nonconductive polymers are used to seal portions of the nanowires or nanotubes to create molecule noninteraction zones. By correlating certain molecule species to voltages generated, a nanosensor may quickly identify which species is detected. Nanoconverters in a series parallel arrangement may be constructed in planar, stacked, or rolled arrays to supply power to nano- and micro-devices without use of external batteries. In some cases breath, from human or other life forms, contain sufficient molecules to power a nanoconverter. A membrane permeable to certain molecules around the molecule interaction zone increases specific molecule nanosensor selectivity response.

  11. Nanodevices for generating power from molecules and batteryless sensing

    DOE Patents [OSTI]

    Wang, Yinmin; Wang, Xianying; Hamza, Alex V.

    2015-06-09

    A nanoconverter or nanosensor is disclosed capable of directly generating electricity through physisorption interactions with molecules that are dipole containing organic species in a molecule interaction zone. High surface-to-volume ratio semiconductor nanowires or nanotubes (such as ZnO, silicon, carbon, etc.) are grown either aligned or randomly-aligned on a substrate. Epoxy or other nonconductive polymers are used to seal portions of the nanowires or nanotubes to create molecule noninteraction zones. By correlating certain molecule species to voltages generated, a nanosensor may quickly identify which species is detected. Nanoconverters in a series parallel arrangement may be constructed in planar, stacked, or rolled arrays to supply power to nano- and micro-devices without use of external batteries. In some cases breath, from human or other life forms, contain sufficient molecules to power a nanoconverter. A membrane permeable to certain molecules around the molecule interaction zone increases specific molecule nanosensor selectivity response.

  12. Toroidal nanotraps for cold polar molecules

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Salhi, Marouane; Passian, Ali; Siopsis, George

    2015-09-14

    Electronic excitations in metallic nanoparticles in the optical regime that have been of great importance in surface-enhanced spectroscopy and emerging applications of molecular plasmonics, due to control and confinement of electromagnetic energy, may also be of potential to control the motion of nanoparticles and molecules. Here, we propose a concept for trapping polarizable particles and molecules using toroidal metallic nanoparticles. Specifically, gold nanorings are investigated for their scattering properties and field distribution to computationally show that the response of these optically resonant particles to incident photons permit the formation of a nanoscale trap when proper aspect ratio, photon wavelength, andmore » polarization are considered. However, interestingly the resonant plasmonic response of the nanoring is shown to be detrimental to the trap formation. The results are in good agreement with analytic calculations in the quasistatic limit within the first-order perturbation of the scalar electric potential. The possibility of extending the single nanoring trapping properties to two-dimensional arrays of nanorings is suggested by obtaining the field distribution of nanoring dimers and trimers.« less

  13. Toroidal nanotraps for cold polar molecules

    SciTech Connect (OSTI)

    Salhi, Marouane; Passian, Ali; Siopsis, George

    2015-09-14

    Electronic excitations in metallic nanoparticles in the optical regime that have been of great importance in surface-enhanced spectroscopy and emerging applications of molecular plasmonics, due to control and confinement of electromagnetic energy, may also be of potential to control the motion of nanoparticles and molecules. Here, we propose a concept for trapping polarizable particles and molecules using toroidal metallic nanoparticles. Specifically, gold nanorings are investigated for their scattering properties and field distribution to computationally show that the response of these optically resonant particles to incident photons permit the formation of a nanoscale trap when proper aspect ratio, photon wavelength, and polarization are considered. However, interestingly the resonant plasmonic response of the nanoring is shown to be detrimental to the trap formation. The results are in good agreement with analytic calculations in the quasistatic limit within the first-order perturbation of the scalar electric potential. The possibility of extending the single nanoring trapping properties to two-dimensional arrays of nanorings is suggested by obtaining the field distribution of nanoring dimers and trimers.

  14. Reversible Aptamer-Au Plasmon Rulers for Secreted Single Molecules

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lee, Somin Eunice; Chen, Qian; Bhat, Ramray; Petkiewicz, Shayne; Smith, Jessica M.; Ferry, Vivian E.; Correia, Ana Luisa; Alivisatos, A. Paul; Bissell, Mina J.

    2015-06-03

    Plasmon rulers, consisting of pairs of gold nanoparticles, allow single-molecule analysis without photobleaching or blinking; however, current plasmon rulers are irreversible, restricting detection to only single events. Here, we present a reversible plasmon ruler, comprised of coupled gold nanoparticles linked by a single aptamer, capable of binding individual secreted molecules with high specificity. We show that the binding of target secreted molecules to the reversible plasmon ruler is characterized by single-molecule sensitivity, high specificity, and reversibility. Lastly, such reversible plasmon rulers should enable dynamic and adaptive live-cell measurement of secreted single molecules in their local microenvironment.

  15. Adiabatic theory for anisotropic cold molecule collisions

    SciTech Connect (OSTI)

    Pawlak, Mariusz; Shagam, Yuval; Narevicius, Edvardas; Moiseyev, Nimrod

    2015-08-21

    We developed an adiabatic theory for cold anisotropic collisions between slow atoms and cold molecules. It enables us to investigate the importance of the couplings between the projection states of the rotational motion of the atom about the molecular axis of the diatom. We tested our theory using the recent results from the Penning ionization reaction experiment {sup 4}He(1s2s {sup 3}S) + HD(1s{sup 2}) → {sup 4}He(1s{sup 2}) + HD{sup +}(1s) + e{sup −} [Lavert-Ofir et al., Nat. Chem. 6, 332 (2014)] and demonstrated that the couplings have strong effect on positions of shape resonances. The theory we derived provides cross sections which are in a very good agreement with the experimental findings.

  16. Low energy ion-molecule reactions

    SciTech Connect (OSTI)

    Farrar, J.M.

    1993-12-01

    This project is concerned with elucidating the dynamics of elementary ion-molecule reactions at collision energies near and below 1 eV. From measurements of the angular and energy distributions of the reaction products, one can infer intimathe details about the nature of collisions leading to chemical reaction, the geometries and lifetimes of intermediate complexes that govern the reaction dynamics, and the collision energy dependence of these dynamical features. The author employs crossed-beam low energy mass spectrometry technology developed over the last several years, with the focus of current research on proton transfer and hydrogen atom transfer reactions of te O{sup {minus}} ion with species such as HF, H{sub 2}O, and NH{sub 3}.

  17. Time-Resolved SAXS/WAXS Study of the Phase Behavior and Microstructural Evolution of Drug/PEG Solid Dispersions

    SciTech Connect (OSTI)

    Zhu, Qing; Harris, Michael T.; Taylor, Lynne S.

    2013-03-07

    Simultaneous small-angle X-ray scattering/wide-angle X-ray scattering (SAXS/WAXS) was employed to elucidate the physical state and location of various small molecule drugs blended with polyethylene glycol (PEG), as well as the time dependent microstructural evolution of the systems. Samples were prepared by comelting physical mixtures of the drug and PEG, followed by solidification at 25 C. The model drugs selected encompassed a wide variety of physicochemical properties in terms of crystallization tendency and potential for interaction with PEG. It was observed that compounds which crystallized rapidly and had weak interactions with PEG tended to be excluded from the interlamellar region of the PEG matrix. In contrast, drugs which had favorable interactions with PEG were incorporated into the interlamellar regions of the polymer up until the point at which the drug crystallized whereby phase separation occurred. These factors are likely to impact the effectiveness of drug/PEG systems as drug delivery systems.

  18. Soft-Template-Synthesized Mesoporous Carbon for Oral Drug Delivery

    SciTech Connect (OSTI)

    Saha, Dipendu; Warren, Kaitlyn E; Naskar, Amit K

    2014-01-01

    Template-synthesized mesoporous carbons were successfully used in in vitro investigations of controlled delivery of three model drugs, captopril, furosemide, and ranitidine hydrochloride. Captopril and furosemide exhibited desorption kinetics over 30 40 h, and ranitidine HCl had a complete release time of 5 10 h. As evident from the slow release kinetics, we contend that our mesoporous carbon is an improved drug-delivery medium compared to state-of-the-art porous silica-based substrates. The mesoporous carbons, synthesized from phloroglucinol and lignin, a synthetic and a sustainable precursor, respectively, exhibit BET surface area of 200 400 m2 g-1 and pore volume of 0.2 0.6 cm3 g-1. The phloroglucinol-based carbon has narrower pore widths and higher pore volume than the lignin-derived counterpart and maintains a longer release time. Numerical modeling of the release kinetics data reveals that the diffusivities of all the drugs from lignin-based carbon media are of equivalent magnitude (10-22 to 10-24 m2 s-1). However, a tailored reduction of pore width in the sorbent reduces the diffusivity of smaller drug molecules (captopril) by an order of magnitude. Thus, engineered pore morphology in our synthesized carbon sorbent, along with its potential to tailor the chemistry of its interaction with sorbet, can be exploited for optimal delivery system of a preferred drug within its therapeutic level and below the level of toxicity.

  19. Glucose sensing molecules having selected fluorescent properties

    DOE Patents [OSTI]

    Satcher, Jr., Joe H.; Lane, Stephen M.; Darrow, Christopher B.; Cary, Douglas R.; Tran, Joe Anh

    2004-01-27

    An analyte sensing fluorescent molecule that employs intramolecular electron transfer is designed to exhibit selected fluorescent properties in the presence of analytes such as saccharides. The selected fluorescent properties include excitation wavelength, emission wavelength, fluorescence lifetime, quantum yield, photostability, solubility, and temperature or pH sensitivity. The compound comprises an aryl or a substituted phenyl boronic acid that acts as a substrate recognition component, a fluorescence switch component, and a fluorophore. The fluorophore and switch component are selected such that the value of the free energy for electron transfer is less than about 3.0 kcal mol.sup.-1. Fluorescent compounds are described that are excited at wavelengths greater than 400 nm and emit at wavelengths greater than 450 nm, which is advantageous for optical transmission through skin. The fluorophore is typically selected from transition metal-ligand complexes and thiazine, oxazine, oxazone, or oxazine-one as well as anthracene compounds. The fluorescent compound can be immobilized in a glucose permeable biocompatible polymer matrix that is implantable below the skin.

  20. Drug Testing for DOE Positions | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Drug Testing for DOE Positions Drug Testing for DOE Positions Drug Testing for DOE Positions Drug Testing Matrix Secretary Bodman's Memorandum Regarding Drug Testing at DOE Fact ...

  1. Orientational Analysis of Molecules in Thin Films | Stanford Synchrotron

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Radiation Lightsource Orientational Analysis of Molecules in Thin Films Monday, September 17, 2012 - 10:00am SSRL Bldg. 137, room 226 Daniel Kaefer The synchrotron-based X-ray absorption spectroscopy is a very powerful tool to unravel the orientation of organic molecules on surfaces or in thin films. This information on the alignment of - most often - highly anisotropic molecules can become crucial if an epitaxial or even crystalline organic growth is desired, if such thin film should serve

  2. Target molecules detection by waveguiding in a photonic silicon membrane

    DOE Patents [OSTI]

    Letant, Sonia E.; Van Buuren, Anthony; Terminello, Louis; Hart, Bradley R.

    2006-12-26

    Disclosed herein is a porous silicon filter capable of binding and detecting biological and chemical target molecules in liquid or gas samples. A photonic waveguiding silicon filter with chemical and/or biological anchors covalently attached to the pore walls bind target molecules. The system uses transmission curve engineering principles to allow measurements to be made in situ and in real time to detect the presence of various target molecules and calculate the concentration of bound target.

  3. Inducing and Quantifying Forbidden Reactivity with Single Molecule...

    Office of Scientific and Technical Information (OSTI)

    Inducing and Quantifying Forbidden Reactivity with Single Molecule Polymer Mechanochemistry Citation Details In-Document Search Title: Inducing and Quantifying Forbidden Reactivity ...

  4. The photodissociation and reaction dynamics of vibrationally excited molecules

    SciTech Connect (OSTI)

    Crim, F.F.

    1993-12-01

    This research determines the nature of highly vibrationally excited molecules, their unimolecular reactions, and their photodissociation dynamics. The goal is to characterize vibrationally excited molecules and to exploit that understanding to discover and control their chemical pathways. Most recently the author has used a combination of vibrational overtone excitation and laser induced fluorescence both to characterize vibrationally excited molecules and to study their photodissociation dynamics. The author has also begun laser induced grating spectroscopy experiments designed to obtain the electronic absorption spectra of highly vibrationally excited molecules.

  5. Controlling orbital-selective Kondo effects in a single molecule...

    Office of Scientific and Technical Information (OSTI)

    coordination chemistry Citation Details In-Document Search Title: Controlling orbital-selective Kondo effects in a single molecule through coordination chemistry Iron(II) ...

  6. Entropy-based separation of linear chain molecules by exploiting...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Entropy-based separation of linear chain molecules by exploiting differences in the saturation capacities in cage-type zeolites Previous Next List Rajamani Krishna, Jasper M. van...

  7. Two-dimensional stimulated resonance Raman spectroscopy of molecules...

    Office of Scientific and Technical Information (OSTI)

    Two-dimensional stimulated resonance Raman spectroscopy of molecules with broadband x-ray pulses Citation Details In-Document Search Title: Two-dimensional stimulated resonance ...

  8. Stable metal-organic frameworks containing single-molecule traps...

    Office of Scientific and Technical Information (OSTI)

    Title: Stable metal-organic frameworks containing single-molecule traps for enzyme encapsulation Authors: Feng, Dawei ; Liu, Tian-Fu ; Su, Jie ; Bosch, Mathieu ; Wei, Zhangwen ; ...

  9. Nanopost Arrays Anchor Molecules, Improve Ion Yields for Laser...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    molecules by laser mass spectrometry: A matrix of nanoposts protects the biomolecule from beam damage and facilitates the vaporization and ionization needed in mass spectrometry. ...

  10. Mapping protein collapse with single molecule fluorescence and...

    Office of Scientific and Technical Information (OSTI)

    spectroscopy Citation Details In-Document Search Title: Mapping protein collapse with single molecule fluorescence and kinetic synchrotron radiation circular dichroism spectroscopy ...

  11. Spectroscopic probes of vibrationally excited molecules at chemically significant energies

    SciTech Connect (OSTI)

    Rizzo, T.R.

    1993-12-01

    This project involves the application of multiple-resonance spectroscopic techniques for investigating energy transfer and dissociation dynamics of highly vibrationally excited molecules. Two major goals of this work are: (1) to provide information on potential energy surfaces of combustion related molecules at chemically significant energies, and (2) to test theoretical modes of unimolecular dissociation rates critically via quantum-state resolved measurements.

  12. Electrical, Mechanical and Thermal Properties of Single Molecules

    SciTech Connect (OSTI)

    Tao, Nongjian

    2014-08-20

    The specific aims of the prior DOE grant are to determine the stability of a single molecule bound to two electrodes, study local heating in single molecule junctions due to electron-phonon and electron-electron interactions, measure electron-phonon interactions in single molecule wires; and explore piezoelectric properties of single molecules. We have completed all the major tasks, and also expanded naturally the scope of the project to address several other critical issues in single molecule properties, developed new experimental capabilities, and observed a number of unexpected phenomena. We summarized here some of the findings that are most relevant to the present renewal proposal. More details can be found in the publications resulted from this grant and annual progress reports.

  13. Micro injector sample delivery system for charged molecules

    DOE Patents [OSTI]

    Davidson, James C.; Balch, Joseph W.

    1999-11-09

    A micro injector sample delivery system for charged molecules. The injector is used for collecting and delivering controlled amounts of charged molecule samples for subsequent analysis. The injector delivery system can be scaled to large numbers (>96) for sample delivery to massively parallel high throughput analysis systems. The essence of the injector system is an electric field controllable loading tip including a section of porous material. By applying the appropriate polarity bias potential to the injector tip, charged molecules will migrate into porous material, and by reversing the polarity bias potential the molecules are ejected or forced away from the tip. The invention has application for uptake of charged biological molecules (e.g. proteins, nucleic acids, polymers, etc.) for delivery to analytical systems, and can be used in automated sample delivery systems.

  14. Microfabricated injectable drug delivery system

    DOE Patents [OSTI]

    Krulevitch, Peter A.; Wang, Amy W.

    2002-01-01

    A microfabricated, fully integrated drug delivery system capable of secreting controlled dosages of multiple drugs over long periods of time (up to a year). The device includes a long and narrow shaped implant with a sharp leading edge for implantation under the skin of a human in a manner analogous to a sliver. The implant includes: 1) one or more micromachined, integrated, zero power, high and constant pressure generating osmotic engine; 2) low power addressable one-shot shape memory polymer (SMP) valves for switching on the osmotic engine, and for opening drug outlet ports; 3) microfabricated polymer pistons for isolating the pressure source from drug-filled microchannels; 4) multiple drug/multiple dosage capacity, and 5) anisotropically-etched, atomically-sharp silicon leading edge for penetrating the skin during implantation. The device includes an externally mounted controller for controlling on-board electronics which activates the SMP microvalves, etc. of the implant.

  15. The statistics of single molecule detection: An overview

    SciTech Connect (OSTI)

    Enderlein, J.; Robbins, D.L.; Ambrose, W.P.

    1995-12-31

    An overview of our recent results in modeling single molecule detection in fluid flow is presented. Our mathematical approach is based on a path integral representation. The model accounts for all experimental details, such as light collection, laser excitation, hydrodynamics and diffusion, and molecular photophysics. Special attention is paid to multiple molecule crossings through the detection volume. Numerical realization of the theory is discussed. Measurements of burst size distributions in single B-phycoerythrin molecule detection experiments are presented and compared with theoretical predictions.

  16. Recent progress in electron scattering from atoms and molecules

    SciTech Connect (OSTI)

    Brunger, M. J.; Buckman, S. J.; Sullivan, J. P.; Palihawadana, P.; Jones, D. B.; Chiari, L.; Pettifer, Z.; Silva, G. B. da; Lopes, M. C. A.; Duque, H. V.; Masin, Z.; Gorfinkiel, J. D.; Garcia, G.; Hoshino, M.; Tanaka, H.; Limo-Vieira, P.

    2014-03-05

    We present and discuss recent results, both experimental and theoretical (where possible), for electron impact excitation of the 3s[3/2 ]{sub 1} and 3s?[1/2 ]{sub 1} electronic states in neon, elastic electron scattering from the structurally similar molecules benzene, pyrazine, and 1,4-dioxane and excitation of the electronic states of the important bio-molecule analogue ?-tetrahydrofurfuryl alcohol. While comparison between theoretical and experimental results suggests that benchmarked cross sections for electron scattering from atoms is feasible in the near-term, significant further theoretical development for electron-molecule collisions, particularly in respect to discrete excitation processes, is still required.

  17. Restricted mobility of specific functional groups reduces anti-cancer drug activity in healthy cells

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Martins, Murillo L.; Ignazzi, Rosanna; Eckert, Juergen; Watts, Benjamin; Kaneno, Ramon; Zambuzzi, Willian F.; Daemen, Luke; Saeki, Margarida J.; Bordallo, Heloisa N.

    2016-03-02

    Here, the most common cancer treatments currently available are radio- and chemo-therapy. These therapies have, however, drawbacks, such as, the reduction in quality of life and the low efficiency of radiotherapy in cases of multiple metastases. To lessen these effects, we have encapsulated an anti-cancer drug into a biocompatible matrix. In-vitro assays indicate that this bio-nanocomposite is able to interact and cause morphological changes in cancer cells. Meanwhile, no alterations were observed in monocytes and fibroblasts, indicating that this system might carry the drug in living organisms with reduced clearance rate and toxicity. X-rays and neutrons were used to investigatemore » the carrier structure, as well as to assess the drug mobility within the bio-nanocomposite. In conclusion, from these unique data we show that partial mobility restriction of active groups of the drug molecule suggests why this carrier design is potentially safer to healthy cells.« less

  18. Stable Metal-Organic Frameworks Containing Single-Molecule Traps...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Stable Metal-Organic Frameworks Containing Single-Molecule Traps for Enzyme Encapsulation Previous Next List Dawei Feng, Tian-Fu Liu, Jie Su, Mathieu Bosch, Zhangwen Wei, Wei Wan,...

  19. Orientational Analysis of Molecules in Thin Films | Stanford...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Molecules in Thin Films Monday, September 17, 2012 - 10:00am SSRL Bldg. 137, room 226 Daniel Kaefer The synchrotron-based X-ray absorption spectroscopy is a very powerful tool to...

  20. Atom-diatom scattering dynamics of spinning molecules

    SciTech Connect (OSTI)

    Eyles, C. J.; Flo, J.; Averbukh, I. Sh.; Leibscher, M.

    2015-01-14

    We present full quantum mechanical scattering calculations using spinning molecules as target states for nuclear spin selective atom-diatom scattering of reactive D+H{sub 2} and F+H{sub 2} collisions. Molecules can be forced to rotate uni-directionally by chiral trains of short, non-resonant laser pulses, with different nuclear spin isomers rotating in opposite directions. The calculations we present are based on rotational wavepackets that can be created in this manner. As our simulations show, target molecules with opposite sense of rotation are predominantly scattered in opposite directions, opening routes for spatially and quantum state selective scattering of close chemical species. Moreover, two-dimensional state resolved differential cross sections reveal detailed information about the scattering mechanisms, which can be explained to a large degree by a classical vector model for scattering with spinning molecules.

  1. Isolated menthone reductase and nucleic acid molecules encoding same

    DOE Patents [OSTI]

    Croteau, Rodney B; Davis, Edward M; Ringer, Kerry L

    2013-04-23

    The present invention provides isolated menthone reductase proteins, isolated nucleic acid molecules encoding menthone reductase proteins, methods for expressing and isolating menthone reductase proteins, and transgenic plants expressing elevated levels of menthone reductase protein.

  2. Efficient Monte Carlo Simulations of Gas Molecules Inside Porous...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Efficient Monte Carlo Simulations of Gas Molecules Inside Porous Materials Previous Next List J. Kim and B. Smit, J. Chem. Theory Comput. 8 (7), 2336 (2012) DOI: 10.1021ct3003699 ...

  3. Frontiers in Laser Cooling, Single-Molecule Biophysics, and Enrgy...

    Office of Scientific and Technical Information (OSTI)

    Frontiers in Laser Cooling, Single-Molecule Biophysics, and Enrgy Science: A Talk from Paul Alivisatos titled LBNL in the Chu Era Citation Details In-Document Search Title:...

  4. Understanding Enzyme Activity Using Single Molecule Tracking (Poster)

    SciTech Connect (OSTI)

    Liu, Y.-S.; Zeng, Y.; Luo, Y.; Xu, Q.; Himmel, M.; Smith S.; Wei, H.; Ding, S.-Y.

    2009-06-01

    This poster describes single-molecule tracking and total internal reflection fluorescence microscopy. It discusses whether the carbohydrate-binding module (CBM) moves on cellulose, how the CBM binds to cellulose, and the mechanism of cellulosome assembly.

  5. Random Selection for Drug Screening (Technical Report) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Subject: 99 GENERAL AND MISCELLANEOUSMATHEMATICS, COMPUTING, AND INFORMATION SCIENCE; PROBABILITY; SAMPLING; DRUG ABUSE; DRUGS; CRIME DETECTION drug screenings, random selection ...

  6. Calculations of diatomic molecules with the LCTCO method. Double excited states of the H/sub 2/ molecule

    SciTech Connect (OSTI)

    Kirnos, V.N.; Samsonov, B.F.; Cheglokov, E.I.

    1987-01-01

    Autoionizing states of a molecule are short-lived and decay, as a rule, producing separate particles and ions. In particular, the H/sub 2/ molecule in such states decays into H/sub 2//sup +/ + e/sup -/, H + H/sup +/ + e/sup -/, or dissociates into two neutral H atoms in the ground and excited states. Nonempirical calculations of 20 autoionizing states of the H/sub 2/ molecule are performed in a two-center orbital basis and for two values of the internuclear distance. Results obtained are compared with other results known from the literature.

  7. Method of monitoring photoactive organic molecules in-situ during gas-phase deposition of the photoactive organic molecules

    SciTech Connect (OSTI)

    Forrest, Stephen R.; Vartanian, Garen; Rolin, Cedric

    2015-06-23

    A method for in-situ monitoring of gas-phase photoactive organic molecules in real time while depositing a film of the photoactive organic molecules on a substrate in a processing chamber for depositing the film includes irradiating the gas-phase photoactive organic molecules in the processing chamber with a radiation from a radiation source in-situ while depositing the film of the one or more organic materials and measuring the intensity of the resulting photoluminescence emission from the organic material. One or more processing parameters associated with the deposition process can be determined from the photoluminescence intensity data in real time providing useful feedback on the deposition process.

  8. Nitrogen molecule activation by excited states of copper

    SciTech Connect (OSTI)

    Sanchez-Zamora, M.; Novaro, O.; Ruiz, M.E. )

    1990-04-05

    Ab initio molecular orbital studies that include variational (with a multiconfiguration reference state of 200 states) and perturbational (including over 3 million configurations) configuration interaction calculations were addressed to the interaction of nitrogen molecules with copper. The Cu ground state {sup 2}S and first two excited states {sup 2}P and {sup 2}D were studied as they interact in different geometrical approaches (including side-on and end-on geometries) with ground-state N{sub 2} molecules.

  9. Molecule Nanoweaver Creates High-Tech Medical Patches and Multilayered

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Capsules | Argonne National Laboratory Molecule Nanoweaver Creates High-Tech Medical Patches and Multilayered Capsules Technology available for licensing: Molecule Nanoweaver, a unique tool that can be used as both a detector and a fabricator of high-tech patches, multilayered capsules, and other medical products. May increase the market for medical patches Allows creation of medical patches that are more efficient at delivering medication and treatment, speeding up the healing process PDF

  10. Recent Advances in Molecular Engineering of Redox Active Organic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    for Nonaqueous Flow Batteries - Joint Center for Energy Storage Research August 20, 2016, Research Highlights Recent Advances in Molecular Engineering of Redox Active Organic Molecules for Nonaqueous Flow Batteries Summary of organic couples and the corresponding supporting salts demonstrated in either a coin cell, Swagelok cell, H-cell, or flow cell. Scientific Achievement This review article summarizes the recent work on organic molecules for redox flow batteries, both redox couples and

  11. Los Alamos scientists detect and track single molecules with nanoscale

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    carbon cylinders Nanotube "glowsticks" transform surface science tool kit Los Alamos scientists detect and track single molecules with nanoscale carbon cylinders Researchers have now shown that semiconducting carbon nanotubes have the potential to detect and track single molecules in water. January 10, 2012 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering

  12. Materials Project Releases Massive Trove of Battery and Molecule Data

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Materials Project Releases Massive Trove of Battery and Molecule Data Materials Project Releases Massive Trove of Battery and Molecule Data June 8, 2016 Julie Chao, JHChao@lbl.gov, (510) 486-6491 materialsproject2 Screen shot from the Materials Project website. The Materials Project, a Google-like database of material properties aimed at accelerating innovation, has released an enormous trove of data to the public, giving scientists working on fuel cells, photovoltaics, thermoelectrics and a

  13. Conference: Frontiers in Laser Cooling, Single-Molecule Biophysics, and

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy Science: Remarks from Steve Chu at the Scientific Symposium Held in his Honor | ScienceCinema Frontiers in Laser Cooling, Single-Molecule Biophysics, and Energy Science: Remarks from Steve Chu at the Scientific Symposium Held in his Honor Citation Details Title: Frontiers in Laser Cooling, Single-Molecule Biophysics, and Energy Science: Remarks from Steve Chu at the Scientific Symposium Held in his Honor

  14. Methods And Devices For Characterizing Duplex Nucleic Acid Molecules

    DOE Patents [OSTI]

    Akeson, Mark; Vercoutere, Wenonah; Haussler, David; Winters-Hilt, Stephen

    2005-08-30

    Methods and devices are provided for characterizing a duplex nucleic acid, e.g., a duplex DNA molecule. In the subject methods, a fluid conducting medium that includes a duplex nucleic acid molecule is contacted with a nanopore under the influence of an applied electric field and the resulting changes in current through the nanopore caused by the duplex nucleic acid molecule are monitored. The observed changes in current through the nanopore are then employed as a set of data values to characterize the duplex nucleic acid, where the set of data values may be employed in raw form or manipulated, e.g., into a current blockade profile. Also provided are nanopore devices for practicing the subject methods, where the subject nanopore devices are characterized by the presence of an algorithm which directs a processing means to employ monitored changes in current through a nanopore to characterize a duplex nucleic acid molecule responsible for the current changes. The subject methods and devices find use in a variety of applications, including, among other applications, the identification of an analyte duplex DNA molecule in a sample, the specific base sequence at a single nulceotide polymorphism (SNP), and the sequencing of duplex DNA molecules.

  15. Single molecule detection using charge-coupled device array technology

    SciTech Connect (OSTI)

    Denton, M.B.

    1992-07-29

    A technique for the detection of single fluorescent chromophores in a flowing stream is under development. This capability is an integral facet of a rapid DNA sequencing scheme currently being developed by Los Alamos National Laboratory. In previous investigations, the detection sensitivity was limited by the background Raman emission from the water solvent. A detection scheme based on a novel mode of operating a Charge-Coupled Device (CCD) is being developed which should greatly enhance the discrimination between fluorescence from a single molecule and the background Raman scattering from the solvent. Register shifts between rows in the CCD are synchronized with the sample flow velocity so that fluorescence from a single molecule is collected in a single moving charge packet occupying an area approaching that of a single pixel while the background is spread evenly among a large number of pixels. Feasibility calculations indicate that single molecule detection should be achieved with an excellent signal-to-noise ratio.

  16. Isotope separation by photodissociation of Van der Waal's molecules

    DOE Patents [OSTI]

    Lee, Yuan T.

    1977-01-01

    A method of separating isotopes based on the dissociation of a Van der Waal's complex. A beam of molecules of a Van der Waal's complex containing, as one partner of the complex, a molecular species in which an element is present in a plurality of isotopes is subjected to radiation from a source tuned to a frequency which will selectively excite vibrational motion by a vibrational transition or through electronic transition of those complexed molecules of the molecular species which contain a desired isotope. Since the Van der Waal's binding energy is much smaller than the excitational energy of vibrational motion, the thus excited Van der Waal's complex dissociate into molecular components enriched in the desired isotope. The recoil velocity associated with vibrational to translational and rotational relaxation will send the separated molecules away from the beam whereupon the product enriched in the desired isotope can be separated from the constituents of the beam.

  17. A general strategy to construct small molecule biosensors in eukaryotes

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Feng, Justin; Jester, Benjamin W.; Tinberg, Christine E.; Mandell, Daniel J.; Antunes, Mauricio S.; Chari, Raj; Morey, Kevin J.; Rios, Xavier; Medford, June I.; Church, George M.; et al

    2015-12-29

    Biosensors for small molecules can be used in applications that range from metabolic engineering to orthogonal control of transcription. Here, we produce biosensors based on a ligand-binding domain (LBD) by using a method that, in principle, can be applied to any target molecule. The LBD is fused to either a fluorescent protein or a transcriptional activator and is destabilized by mutation such that the fusion accumulates only in cells containing the target ligand. We illustrate the power of this method by developing biosensors for digoxin and progesterone. Addition of ligand to yeast, mammalian, or plant cells expressing a biosensor activatesmore » transcription with a dynamic range of up to ~100-fold. We use the biosensors to improve the biotransformation of pregnenolone to progesterone in yeast and to regulate CRISPR activity in mammalian cells. This work provides a general methodology to develop biosensors for a broad range of molecules in eukaryotes.« less

  18. Spectroscopy and reactions of vibrationally excited transient molecules

    SciTech Connect (OSTI)

    Dai, H.L.

    1993-12-01

    Spectroscopy, energy transfer and reactions of vibrationally excited transient molecules are studied through a combination of laser-based excitation techniques and efficient detection of emission from the energized molecules with frequency and time resolution. Specifically, a Time-resolved Fourier Transform Emission Spectroscopy technique has been developed for detecting dispersed laser-induced fluorescence in the IR, visible and UV regions. The structure and spectroscopy of the excited vibrational levels in the electronic ground state, as well as energy relaxation and reactions induced by specific vibronic excitations of a transient molecule can be characterized from time-resolved dispersed fluorescence in the visible and UV region. IR emissions from highly vibrational excited levels, on the other hand, reveal the pathways and rates of collision induced vibrational energy transfer.

  19. Structure factors for tunneling ionization rates of diatomic molecules

    SciTech Connect (OSTI)

    Saito, Ryoichi; Tolstikhin, Oleg I.; Madsen, Lars Bojer; Morishita, Toru

    2015-05-15

    Within the leading-order, single-active-electron, and frozen-nuclei approximation of the weak-field asymptotic theory, the rate of tunneling ionization of a molecule in an external static uniform electric field is determined by the structure factor for the highest occupied molecular orbital. We present the results of systematic calculations of structure factors for 40 homonuclear and heteronuclear diatomic molecules by the Hartree–Fock method using a numerical grid-based approach implemented in the program X2DHF.

  20. Spectroscopic and dynamical studies of highly energized small polyatomic molecules

    SciTech Connect (OSTI)

    Field, R.W.; Silbey, R.J.

    1990-01-01

    The formyl radical and the acetylene molecule were chosen for these studies. The visible and fluorescence spectra of the formyl radical were recorded, and the spectral results are used as a basis to explain the electronic structure. Optical-optical double resonance studies of acetylene were recorded, and the spectral results are interpreted. The results of Zeeman and Stark anticrossing and quantum beat studies of acetylene are reported, and they provide an unusually detailed view of both Intersystem Crossing and Internal Conversion in small polyatomic molecules. 22 references are cited as resulting from Department of Energy sponsorship of this project.

  1. Diatomic molecules in optical and microwave dipole traps

    SciTech Connect (OSTI)

    Lysebo, Marius; Veseth, Leif

    2011-03-15

    The dipole forces on rotating diatomic molecules are worked out in detail for optical as well as microwave radiation fields. The objective is in particular to investigate how the dipole forces and potentials depend on the subtle internal structure of the molecule, with special emphasis on hyperfine and Zeeman states. Dipole potentials are obtained from computations of the real part of the complex molecular polarizability, whereas the imaginary part yields the scattering force. Numerical examples are presented for {sup 23}Na{sub 2} and OH for optical (laser) fields related to strong electronic transitions and for microwave fields for the {Lambda} doubling in the OH ground state.

  2. Meet the world's highest-performance single-molecule diode

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Meet the world's highest-performance single-molecule diode Click to share on Facebook (Opens in new window) Click to share on Twitter (Opens in new window) Click to share on Reddit (Opens in new window) Click to share on Pinterest (Opens in new window) This is the world's highest-performance single-molecule diode using a combination of gold electrodes and an ionic solution. (Image: Latha Venkataraman, Columbia University) More » Nanotubes that Assemble Themselves Discover a new way to look at

  3. Coherent atomic soliton molecules for matter-wave switching

    SciTech Connect (OSTI)

    Yin, Chenyun; Berloff, Natalia G.; Perez-Garcia, Victor M.; Novoa, David; Carpentier, Alicia V.; Michinel, Humberto

    2011-05-15

    We discuss the dynamics of interacting dark-bright two-dimensional vector solitons in multicomponent immiscible bulk Bose-Einstein condensates. We describe matter-wave molecules without a scalar counterpart that can be seen as bound states of vector objects. We also analyze the possibility of using these structures as building blocks for the design of matter-wave switchers.

  4. Analyte sensing mediated by adapter/carrier molecules

    DOE Patents [OSTI]

    Bayley, Hagan; Braha, Orit; Gu, LiQun

    2002-07-30

    This invention relates to an improved method and system for sensing of one or more analytes. A host molecule, which serves as an adapter/carrier, is used to facilitate interaction between the analyte and the sensor element. A detectable signal is produced reflecting the identity and concentration of analyte present.

  5. Translation and integration of numerical atomic orbitals in linear molecules

    SciTech Connect (OSTI)

    Heinäsmäki, Sami

    2014-02-14

    We present algorithms for translation and integration of atomic orbitals for LCAO calculations in linear molecules. The method applies to arbitrary radial functions given on a numerical mesh. The algorithms are based on pseudospectral differentiation matrices in two dimensions and the corresponding two-dimensional Gaussian quadratures. As a result, multicenter overlap and Coulomb integrals can be evaluated effectively.

  6. Single Molecule Study of Cellulase Hydrolysis of Crystalline Cellulose

    SciTech Connect (OSTI)

    Liu, Y.-S.; Luo, Y.; Baker, J. O.; Zeng, Y.; Himmel, M. E.; Smith, S.; Ding, S.-Y.

    2009-12-01

    This report seeks to elucidate the role of cellobiohydrolase-I (CBH I) in the hydrolysis of crystalline cellulose. A single-molecule approach uses various imaging techniques to investigate the surface structure of crystalline cellulose and changes made in the structure by CBH I.

  7. Forensic Drug Testing Custody and Control Form

    Broader source: Energy.gov [DOE]

    Forensic Drug Testing Custody and Control Form. A copy of the drug testing custody and control form for DOE contractors to use to comply with the drug testing requirements in 10 CFR part 707, Workplace Substance Abuse Programs at DOE Sites.

  8. Apparatus and method of determining molecular weight of large molecules

    DOE Patents [OSTI]

    Fuerstenau, S.; Benner, W.H.; Madden, N.M.; Searles, W.

    1998-06-23

    A mass spectrometer determines the mass of multiply charged high molecular weight molecules. This spectrometer utilizes an ion detector which is capable of simultaneously measuring the charge z and transit time of a single ion as it passes through the detector. From this transit time, the velocity of the single ion may then be derived, thus providing the mass-to-charge ratio m/z for a single ion which has been accelerated through a known potential. Given z and m/z, the mass m of the single ion can then be calculated. Electrospray ions with masses in excess of 1 MDa and charge numbers greater than 425 e{sup {minus}} are readily detected. The on-axis single ion detection configuration enables a duty cycle of nearly 100% and extends the practical application of electrospray mass spectrometry to the analysis of very large molecules with relatively inexpensive instrumentation. 14 figs.

  9. Apparatus and method of determining molecular weight of large molecules

    DOE Patents [OSTI]

    Fuerstenau, Stephen; Benner, W. Henry; Madden, Norman; Searles, William

    1998-01-01

    A mass spectrometer determines the mass of multiply charged high molecular weight molecules. This spectrometer utilizes an ion detector which is capable of simultaneously measuring the charge z and transit time of a single ion as it passes through the detector. From this transit time, the velocity of the single ion may then be derived, thus providing the mass-to-charge ratio m/z for a single ion which has been accelerated through a known potential. Given z and m/z, the mass m of the single ion can then be calculated. Electrospray ions with masses in excess of 1 MDa and charge numbers greater than 425 e.sup.- are readily detected. The on-axis single ion detection configuration enables a duty cycle of nearly 100% and extends the practical application of electrospray mass spectrometry to the analysis of very large molecules with relatively inexpensive instrumentation.

  10. Drug Retention Times (Technical Report) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: 60 APPLIED LIFE SCIENCES; RETENTION; DRUG ABUSE; DRUGS; CRIME DETECTION drugs, retention Word Cloud More Like This ...

  11. Intergrated Drug Testing System, PIA, Bechtel Jacobs C ompany...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Intergrated Drug Testing System, PIA, Bechtel Jacobs C ompany, LLC Intergrated Drug Testing System, PIA, Bechtel Jacobs C ompany, LLC Intergrated Drug Testing System, PIA, Bechtel ...

  12. New Catalytic Approach Builds Molecules with Specific Functionality More

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Safely and Efficiently | U.S. DOE Office of Science (SC) New Catalytic Approach Builds Molecules with Specific Functionality More Safely and Efficiently Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic Energy Sciences Advisory Committee (BESAC) Community Resources Contact Information Basic Energy Sciences U.S. Department of Energy SC-22/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301)

  13. Polymer and small molecule based hybrid light source

    DOE Patents [OSTI]

    Choong, Vi-En; Choulis, Stelios; Krummacher, Benjamin Claus; Mathai, Mathew; So, Franky

    2010-03-16

    An organic electroluminescent device, includes: a substrate; a hole-injecting electrode (anode) coated over the substrate; a hole injection layer coated over the anode; a hole transporting layer coated over the hole injection layer; a polymer based light emitting layer, coated over the hole transporting layer; a small molecule based light emitting layer, thermally evaporated over the polymer based light emitting layer; and an electron-injecting electrode (cathode) deposited over the electroluminescent polymer layer.

  14. Probing Valance and Core Excitons in Molecules by Coherent Multidimensional

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Spectroscopy with Clasical and Quantum Light | MIT-Harvard Center for Excitonics Valance and Core Excitons in Molecules by Coherent Multidimensional Spectroscopy with Clasical and Quantum Light September 20, 2011 at 3pm/36-428 Shaul Mukamel University of California, Irvine shaul_001 Abstract: Multidimensional spectroscopic techniques which originated with NMR in the 1970's have been extended over the past 18 years to the infrared and visible regimes. Novel extensions of these ideas to study

  15. Ro-vibrational Relaxation Dynamics of PbF Molecules

    SciTech Connect (OSTI)

    Neil Shafer-Ray

    2011-04-08

    In 1950 Purcell and Ramsey suggested that the electron might have a CP-violating electric dipole moment (e-EDM) proportional to its spin angular momentum. This possibility initiated an ongoing hunt for the e-EDM that has been spurred on by the recognition of the importance of CP-violation to the formation of a matter-dominated universe[2] as well as a difference in magnitude of the Supersymmetric and Standard Model[4] prediction for its value. The current limit on the e-EDM is 1.6E??27 e·cm as determined in a Ramsey beam resonance study of the Tl atom. The PbF molecule provides a unique opportunity to measure the e-EDM. The molecule??s odd electron, heavy mass, and large internal field combine to give it an intrinsic sensitivity to an e-EDM that is over three orders of magnitude bigger than that of the Tl atom. In addition to this increased intrinsic sensitivity, the ground state of the PbF molecule allows for a "magic" electric field at which the magnetic moment vanishes[7]. All of these advantages create an opportunity to significantly lower the current limit on the e-EDM. These advantages can only be realized if an intense source of ground-state PbF molecules can be created and detected with high efficiency. The scope of this project is to (1) create a rotationally cold molecular beam source of PbF, (2) achieve a continuous ionization scheme for sensitive state selective detection of the PbF molecule.

  16. Coupled wavepackets study of ion-molecule collisions

    SciTech Connect (OSTI)

    Aguillon, F.

    1996-02-25

    A semiclassical coupled wavepacket method is used to study non adiabatic dynamics of ion molecule collisions. In this method, some of the nuclear degrees of freedom are treated classically. Simultaneously, the quantal degrees of freedom are handled numerically, resulting in a coupled wavepacket description. Applications to the study of dissociative charge transfer (e.g. He{sup +}+H2{yields}He+H+H{sup +}) and non adiabatic reaction (Ar{sup +}+H2{yields}ArH{sup +}+H) are presented.

  17. Composition for detection of cell density signal molecule

    DOE Patents [OSTI]

    Schwarz, Richard I.

    2001-01-01

    Disclosed herein is a novel proteinaceous cell density signal molecule (CDS), which is secreted by fibroblastic cells in culture, preferably tendon cells, and which provides a means by which the cells self-regulate their proliferation and the expression of differentiated function. CDS, and the antibodies which recognize them, are important for the development of diagnostics and treatments for injuries and diseases involving connective tissues, particularly tendon. Also disclosed are methods of production and use.

  18. Subtask 2: Molecules, Materials, and Systems for Solar Electricity | ANSER

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Center | Argonne-Northwestern National Laboratory 2: Molecules, Materials, and Systems for Solar Electricity Home > Research > Subtask 2 The above figure depicts the structure of active polymer layers in organic solar cells. The above figure depicts the structure of active polymer layers in organic solar cells. ANSER Center research tests theory-driven ideas to understand at a fundamental level how photovoltaic cell performance is affected by nanoscale/mesoscale

  19. Density Functional Theory with Dissipation: Transport through Single Molecules

    SciTech Connect (OSTI)

    Kieron Burke

    2012-04-30

    A huge amount of fundamental research was performed on this grant. Most of it focussed on fundamental issues of electronic structure calculations of transport through single molecules, using density functional theory. Achievements were: (1) First density functional theory with dissipation; (2) Pseudopotential plane wave calculations with master equation; (3) Weak bias limit; (4) Long-chain conductance; and (5) Self-interaction effects in tunneling.

  20. Small-Molecule Inhibition of TNF-alpha

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Small-Molecule Inhibition of TNF-alpha Tumour necrosis factor is a polypeptide cytokine involved in inflammation and the acute phase response. TNF-alpha is present in larger quantities in persons with rheumatoid arthritis or Crohn's disease. Direct inhibition of TNF-a by the commercial biological agents etanercept (Enbrel), infliximab (Remicade), adalimumab (Humira), has produced significant advances in rheumatoid arthritis treatment and validated the extra-cellular inhibition of this

  1. Using Coupled Harmonic Oscillators to Model Some Greenhouse Gas Molecules

    SciTech Connect (OSTI)

    Go, Clark Kendrick C.; Maquiling, Joel T.

    2010-07-28

    Common greenhouse gas molecules SF{sub 6}, NO{sub 2}, CH{sub 4}, and CO{sub 2} are modeled as harmonic oscillators whose potential and kinetic energies are derived. Using the Euler-Lagrange equation, their equations of motion are derived and their phase portraits are plotted. The authors use these data to attempt to explain the lifespan of these gases in the atmosphere.

  2. Anatomic and Functional Imaging of Tagged Molecules in Animals - Energy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Innovation Portal Anatomic and Functional Imaging of Tagged Molecules in Animals Thomas Jefferson National Accelerator Facility Contact TJNAF About This Technology Technology Marketing SummaryA novel functional imaging system for use in the imaging of unrestrained and non-anesthetized small animals or other subjects and a method for acquiring such images and further registering them with anatomical X-ray images previously or subsequently acquired.DescriptionThe apparatus comprises a

  3. Single molecule transistor based nanopore for the detection of nicotine

    SciTech Connect (OSTI)

    Ray, S. J.

    2014-12-28

    A nanopore based detection methodology was proposed and investigated for the detection of Nicotine. This technique uses a Single Molecular Transistor working as a nanopore operational in the Coulomb Blockade regime. When the Nicotine molecule is pulled through the nanopore area surrounded by the Source(S), Drain (D), and Gate electrodes, the charge stability diagram can detect the presence of the molecule and is unique for a specific molecular structure. Due to the weak coupling between the different electrodes which is set by the nanopore size, the molecular energy states stay almost unaffected by the electrostatic environment that can be realised from the charge stability diagram. Identification of different orientation and position of the Nicotine molecule within the nanopore area can be made from specific regions of overlap between different charge states on the stability diagram that could be used as an electronic fingerprint for detection. This method could be advantageous and useful to detect the presence of Nicotine in smoke which is usually performed using chemical chromatography techniques.

  4. Structures of water molecules in carbon nanotubes under electric fields

    SciTech Connect (OSTI)

    Winarto,; Takaiwa, Daisuke; Yamamoto, Eiji; Yasuoka, Kenji

    2015-03-28

    Carbon nanotubes (CNTs) are promising for water transport through membranes and for use as nano-pumps. The development of CNT-based nanofluidic devices, however, requires a better understanding of the properties of water molecules in CNTs because they can be very different from those in the bulk. Using all-atom molecular dynamics simulations, we investigate the effect of axial electric fields on the structure of water molecules in CNTs having diameters ranging from (7,7) to (10,10). The water dipole moments were aligned parallel to the electric field, which increases the density of water inside the CNTs and forms ordered ice-like structures. The electric field induces the transition from liquid to ice nanotubes in a wide range of CNT diameters. Moreover, we found an increase in the lifetime of hydrogen bonds for water structures in the CNTs. Fast librational motion breaks some hydrogen bonds, but the molecular pairs do not separate and the hydrogen bonds reform. Thus, hydrogen bonds maintain the water structure in the CNTs, and the water molecules move collectively, decreasing the axial diffusion coefficient and permeation rate.

  5. Single Molecule Switches and Molecular Self-Assembly: Low Temperature STM Investigations and Manipulations

    SciTech Connect (OSTI)

    Iancu, Violeta

    2006-08-01

    This dissertation is devoted to single molecule investigations and manipulations of two porphyrin-based molecules, chlorophyll-a and Co-popphyrin. The molecules are absorbed on metallic substrates and studied at low temperatures using a scanning tunneling microscope. The electronic, structural and mechanical properties of the molecules are investigated in detail with atomic level precision. Chlorophyll-a is the key ingredient in photosynthesis processes while Co-porphyrin is a magnetic molecule that represents the recent emerging field of molecular spintronics. Using the scanning tunneling microscope tip and the substrate as electrodes, and the molecules as active ingredients, single molecule switches made of these two molecules are demonstrated. The first switch, a multiple and reversible mechanical switch, is realized by using chlorophyll-a where the energy transfer of a single tunneling electron is used to rotate a C-C bond of the molecule's tail on a Au(111) surface. Here, the det

  6. Quantum Monte Carlo Calculations Applied to Magnetic Molecules

    SciTech Connect (OSTI)

    Larry Engelhardt

    2006-08-09

    We have calculated the equilibrium thermodynamic properties of Heisenberg spin systems using a quantum Monte Carlo (QMC) method. We have used some of these systems as models to describe recently synthesized magnetic molecules, and-upon comparing the results of these calculations with experimental data-have obtained accurate estimates for the basic parameters of these models. We have also performed calculations for other systems that are of more general interest, being relevant both for existing experimental data and for future experiments. Utilizing the concept of importance sampling, these calculations can be carried out in an arbitrarily large quantum Hilbert space, while still avoiding any approximations that would introduce systematic errors. The only errors are statistical in nature, and as such, their magnitudes are accurately estimated during the course of a simulation. Frustrated spin systems present a major challenge to the QMC method, nevertheless, in many instances progress can be made. In this chapter, the field of magnetic molecules is introduced, paying particular attention to the characteristics that distinguish magnetic molecules from other systems that are studied in condensed matter physics. We briefly outline the typical path by which we learn about magnetic molecules, which requires a close relationship between experiments and theoretical calculations. The typical experiments are introduced here, while the theoretical methods are discussed in the next chapter. Each of these theoretical methods has a considerable limitation, also described in Chapter 2, which together serve to motivate the present work. As is shown throughout the later chapters, the present QMC method is often able to provide useful information where other methods fail. In Chapter 3, the use of Monte Carlo methods in statistical physics is reviewed, building up the fundamental ideas that are necessary in order to understand the method that has been used in this work. With these

  7. BEAM TRANSPORT AND STORAGE WITH COLD NEUTRAL ATOMS AND MOLECULES

    SciTech Connect (OSTI)

    Walstrom, Peter L.

    2012-05-15

    A large class of cold neutral atoms and molecules is subject to magnetic field-gradient forces. In the presence of a field, hyperfine atomic states are split into several Zeeman levels. The slopes of these curves vs. field are the effective magnetic moments. By means of optical pumping in a field, Zeeman states of neutral lithium atoms and CaH molecules with effective magnetic moments of nearly {+-} one Bohr magneton can be selected. Particles in Zeeman states for which the energy increases with field are repelled by increasing fields; particles in states for which the energy decreases with field are attracted to increasing fields. For stable magnetic confinement, field-repelled states are required. Neutral-particle velocities in the present study are on the order of tens to hundreds of m/s and the magnetic fields needed for transport and injection are on the order of in the range of 0.01-1T. Many of the general concepts of charged-particle beam transport carry over into neutral particle spin-force optics, but with important differences. In general, the role of bending dipoles in charged particle optics is played by quadrupoles in neutral particle optics; the role of quadrupoles is played by sextupoles. The neutralparticle analog of charge-exchange injection into storage rings is the use of lasers to flip the state of particles from field-seeking to field-repelled. Preliminary tracking results for two neutral atom/molecule storage ring configurations are presented. It was found that orbit instabilities limit the confinment time in a racetrack-shaped ring with discrete magnetic elements with drift spaces between them; stable behavior was observed in a toroidal ring with a continuous sextupole field. An alternative concept using a linear sextupole or octupole channel with solenoids on the ends is presently being considered.

  8. Novel nuclear magnetic resonance techniques for studying biological molecules

    SciTech Connect (OSTI)

    Laws, David D.

    2000-06-01

    Over the fifty-five year history of Nuclear Magnetic Resonance (NMR), considerable progress has been made in the development of techniques for studying the structure, function, and dynamics of biological molecules. The majority of this research has involved the development of multi-dimensional NMR experiments for studying molecules in solution, although in recent years a number of groups have begun to explore NMR methods for studying biological systems in the solid-state. Despite this new effort, a need still exists for the development of techniques that improve sensitivity, maximize information, and take advantage of all the NMR interactions available in biological molecules. In this dissertation, a variety of novel NMR techniques for studying biomolecules are discussed. A method for determining backbone ({phi}/{psi}) dihedral angles by comparing experimentally determined {sup 13}C{sub a}, chemical-shift anisotropies with theoretical calculations is presented, along with a brief description of the theory behind chemical-shift computation in proteins and peptides. The utility of the Spin-Polarization Induced Nuclear Overhauser Effect (SPINOE) to selectively enhance NMR signals in solution is examined in a variety of systems, as are methods for extracting structural information from cross-relaxation rates that can be measured in SPINOE experiments. Techniques for the production of supercritical and liquid laser-polarized xenon are discussed, as well as the prospects for using optically pumped xenon as a polarizing solvent. In addition, a detailed study of the structure of PrP 89-143 is presented. PrP 89-143 is a 54 residue fragment of the prion proteins which, upon mutation and aggregation, can induce prion diseases in transgenic mice. Whereas the structure of the wild-type PrP 89-143 is a generally unstructured mixture of {alpha}-helical and {beta}-sheet conformers in the solid state, the aggregates formed from the PrP 89-143 mutants appear to be mostly {beta}-sheet.

  9. Molecular Design of Branched and Binary Molecules at Ordered Interfaces

    SciTech Connect (OSTI)

    Kirsten Larson Genson

    2005-12-27

    This study examined five different branched molecular architectures to discern the effect of design on the ability of molecules to form ordered structures at interfaces. Photochromic monodendrons formed kinked packing structures at the air-water interface due to the cross-sectional area mismatch created by varying number of alkyl tails and the hydrophilic polar head group. The lower generations formed orthorhombic unit cell with long range ordering despite the alkyl tails tilted to a large degree. Favorable interactions between liquid crystalline terminal groups and the underlying substrate were observed to compel a flexible carbosilane dendrimer core to form a compressed elliptical conformation which packed stagger within lamellae domains with limited short range ordering. A twelve arm binary star polymer was observed to form two dimensional micelles at the air-water interface attributed to the higher polystyrene block composition. Linear rod-coil molecules formed a multitude of packing structures at the air-water interface due to the varying composition. Tree-like rod-coil molecules demonstrated the ability to form one-dimensional structures at the air-water interface and at the air-solvent interface caused by the preferential ordering of the rigid rod cores. The role of molecular architecture and composition was examined and the influence chemically competing fragments was shown to exert on the packing structure. The amphiphilic balance of the different molecular series exhibited control on the ordering behavior at the air-water interface and within bulk structures. The shell nature and tail type was determined to dictate the preferential ordering structure and molecular reorganization at interfaces with the core nature effect secondary.

  10. Numerically Solvable Model for Resonant Collisions of Electronswith Diatomic Molecules

    SciTech Connect (OSTI)

    Houfek, Karel; Rescigno, T.N.; McCurdy, C.W.

    2006-01-27

    We describe a simple model for electron-molecule collisions that has one nuclear and one electronic degree of freedom and that can be solved to arbitrarily high precision, without making the Born-Oppenheimer approximation, by employing a combination of the exterior complex scaling method and a finite-element implementation of the discrete variable representation. We compare exact cross sections for vibrational excitation and dissociative attachment with results obtained using the local complex potential approximation as commonly applied in the ''boomerang'' model, and suggest how this two-dimensional model can be used to test the underpinnings of contemporary nonlocal approximations to resonant collisions.

  11. Spectroscopic and dynamical studies of highly energized small polyatomic molecules

    SciTech Connect (OSTI)

    Field, R.W.; Silbey, R.J.

    1993-12-01

    The authors have initiated a program to perform spectroscopic and dynamic studies of small molecules. Large amplitude motions in excited acetylene were discussed along with plans to record the dispersed fluorescence (DF) and the stimulated emission pumping (SEP) spectra. SEP spectra were reported for the formyl radical. A Fourier transform spectrometer was discussed with respect to its ability to probe the structure of radicals. This instrument is capable of performing studies using various techniques such as magnetic rotation spectroscopy and sub-Doppler sideband-OODR Zeman (SOODRZ) spectroscopy.

  12. Vacuum ultraviolet photoionization and photodissociation of polyatomic molecules and radicals

    SciTech Connect (OSTI)

    Ng, C.Y.

    1993-12-01

    In the past decade, tremendous progress has been made in understanding the photodissociation (PD) dynamics of triatomic molecules. However, the PD study of radicals, especially polyatomic radicals, has remained essentially an unexplored research area. Detailed state-to-state PD cross sections for radicals in the UV and VUV provide challenges not only for dynamical calculations, but also for ab initio quantum chemical studies. The authors have developed a laser based pump-probe apparatus for the measurement of absolute PD cross sections for CH{sub 3}S and HS is summarized.

  13. Glassy dynamics of hydrogen-bonded heteroditopic molecules

    SciTech Connect (OSTI)

    Lou, Nan; Wang, Yangyang; Li, Haixia; Sokolov, Alexei P; Xiong, Huiming

    2012-01-01

    A self-complementary heteroditopic molecule composed of thymine and diamidopyridine end groups and a flexible aliphatic interconnecting chain has been synthesized. The glassy dynamics of this hydrogen-bonded supramolecule have been investigated by using dielectric and rheological measurements, in combination with infra-red spectroscopy and solid-state 13C NMR experiments. Decoupling of main dielectric relaxation from viscosity has been found in the vicinity of the glass transition and the temperature dependence of viscosity appears to be stronger than that of dielectric relaxation. The unusual dynamic decoupling phenomenon is ascribed to the chemical/dynamic heterogeneity and formation of hydrogen bonds in the supramolecules.

  14. Deterministically Polarized Fluorescence from Single Dye Molecules Aligned in Liquid Crystal Host

    SciTech Connect (OSTI)

    Lukishova, S.G.; Schmid, A.W.; Knox, R.; Freivald, P.; Boyd, R. W.; Stroud, Jr., C. R.; Marshall, K.L.

    2005-09-30

    We demonstrated for the first time to our konwledge deterministically polarized fluorescence from single dye molecules. Planar aligned nematic liquid crystal hosts provide deterministic alignment of single dye molecules in a preferred direction.

  15. Neuroimaging for drug addiction and related behaviors

    SciTech Connect (OSTI)

    Parvaz M. A.; Parvaz, M.A.; Alia-Klein, N.; Woicik,P.A.; Volkow, N.D.; Goldstein, R.Z.

    2011-10-01

    In this review, we highlight the role of neuroimaging techniques in studying the emotional and cognitive-behavioral components of the addiction syndrome by focusing on the neural substrates subserving them. The phenomenology of drug addiction can be characterized by a recurrent pattern of subjective experiences that includes drug intoxication, craving, bingeing, and withdrawal with the cycle culminating in a persistent preoccupation with obtaining, consuming, and recovering from the drug. In the past two decades, imaging studies of drug addiction have demonstrated deficits in brain circuits related to reward and impulsivity. The current review focuses on studies employing positron emission tomography (PET), functional magnetic resonance imaging (fMRI), and electroencephalography (EEG) to investigate these behaviors in drug-addicted human populations. We begin with a brief account of drug addiction followed by a technical account of each of these imaging modalities. We then discuss how these techniques have uniquely contributed to a deeper understanding of addictive behaviors.

  16. DEUTERATED MOLECULES IN ORION KL FROM HERSCHEL/HIFI

    SciTech Connect (OSTI)

    Neill, Justin L.; Crockett, Nathan R.; Bergin, Edwin A.; Pearson, John C.; Xu, Li-Hong

    2013-11-10

    We present a comprehensive study of the deuterated molecules detected in the fullband HIFI survey of the Orion Kleinmann-Low nebula (Orion KL) region. Ammonia, formaldehyde, and methanol and their singly deuterated isotopologues are each detected through numerous transitions in this survey with a wide range in optical depths and excitation conditions. In conjunction with a recent study of the abundance of HDO and H{sub 2}O in Orion KL, this study yields the best constraints on deuterium fractionation in an interstellar molecular cloud to date. As previous studies have found, both the Hot Core and Compact Ridge regions within Orion KL contain significant abundances of deuterated molecules, suggesting an origin in cold grain mantles. In the Hot Core, we find that ammonia is roughly a factor of two more fractionated than water. In the Compact Ridge, meanwhile, we find similar deuterium fractionation in water, formaldehyde, and methanol, with D/H ratios of (2-8) 10{sup 3}. The [CH{sub 2}DOH]/[CH{sub 3}OD] ratio in the Compact Ridge is found to be 1.2 0.3. The Hot Core generally has lower deuterium fractionation than the Compact Ridge, suggesting a slightly warmer origin, or a greater contribution from warm gas phase chemistry.

  17. Emerging pathogens: Dynamics, mutation and drug resistance

    SciTech Connect (OSTI)

    Perelson, A.S.; Goldstein, B.; Korber, B.T.

    1997-10-01

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The objectives of this project were to develop models of the spread of pathogens, such as HIV-1 and influenza, in humans, and then to use the models to address the possibility of designing appropriate drug therapies that may limit the ability of the pathogen to escape treatment by mutating into a drug resistant form. We have developed a model of drug-resistance to amantidine and rimantadine, the two major antiviral drugs used to treat influenza, and have used the model to suggest treatment strategies during an epidemic.

  18. Automated High Throughput Drug Target Crystallography

    SciTech Connect (OSTI)

    Rupp, B

    2005-02-18

    The molecular structures of drug target proteins and receptors form the basis for 'rational' or structure guided drug design. The majority of target structures are experimentally determined by protein X-ray crystallography, which as evolved into a highly automated, high throughput drug discovery and screening tool. Process automation has accelerated tasks from parallel protein expression, fully automated crystallization, and rapid data collection to highly efficient structure determination methods. A thoroughly designed automation technology platform supported by a powerful informatics infrastructure forms the basis for optimal workflow implementation and the data mining and analysis tools to generate new leads from experimental protein drug target structures.

  19. In and out of the minor groove: interaction of an AT-rich DNA with the drug CD27

    SciTech Connect (OSTI)

    Acosta-Reyes, Francisco J.; Dardonville, Christophe; Koning, Harry P. de; Natto, Manal; Subirana, Juan A.; Campos, J. Lourdes

    2014-06-01

    New features of an antiprotozoal DNA minor-groove binding drug, which acts as a cross-linking agent, are presented. It also fills the minor groove of DNA completely and prevents the access of proteins. These features are also expected for other minor-groove binding drugs when associated with suitable DNA targets. The DNA of several pathogens is very rich in AT base pairs. Typical examples include the malaria parasite Plasmodium falciparum and the causative agents of trichomoniasis and trypanosomiases. This fact has prompted studies of drugs which interact with the minor groove of DNA, some of which are used in medical practice. Previous studies have been performed almost exclusively with the AATT sequence. New features should be uncovered through the study of different DNA sequences. In this paper, the crystal structure of the complex of the DNA duplex d(AAAATTTT){sub 2} with the dicationic drug 4, 4?-bis(imidazolinylamino)diphenylamine (CD27) is presented. The drug binds to the minor groove of DNA as expected, but it shows two new features that have not previously been described: (i) the drugs protrude from the DNA and interact with neighbouring molecules, so that they may act as cross-linking agents, and (ii) the drugs completely cover the whole minor groove of DNA and displace bound water. Thus, they may prevent the access to DNA of proteins such as AT-hook proteins. These features are also expected for other minor-groove binding drugs when associated with all-AT DNA. These findings allow a better understanding of this family of compounds and will help in the development of new, more effective drugs. New data on the biological interaction of CD27 with the causative agent of trichomoniasis, Trichomonas vaginalis, are also reported.

  20. Coherent Anti-Stokes Raman Scattering Spectroscopy of Single Molecules in Solution

    SciTech Connect (OSTI)

    Sunney Xie, Wei Min, Chris Freudiger, Sijia Lu

    2012-01-18

    During this funding period, we have developed two breakthrough techniques. The first is stimulated Raman scattering microscopy, providing label-free chemical contrast for chemical and biomedical imaging based on vibrational spectroscopy. Spontaneous Raman microscopy provides specific vibrational signatures of chemical bonds, but is often hindered by low sensitivity. We developed a three-dimensional multiphoton vibrational imaging technique based on stimulated Raman scattering (SRS). The sensitivity of SRS imaging is significantly greater than that of spontaneous Raman microscopy, which is achieved by implementing high-frequency (megahertz) phase-sensitive detection. SRS microscopy has a major advantage over previous coherent Raman techniques in that it offers background-free and readily interpretable chemical contrast. We demonstrated a variety of biomedical applications, such as differentiating distributions of omega-3 fatty acids and saturated lipids in living cells, imaging of brain and skin tissues based on intrinsic lipid contrast, and monitoring drug delivery through the epidermis. This technology offers exciting prospect for medical imaging. The second technology we developed is stimulated emission microscopy. Many chromophores, such as haemoglobin and cytochromes, absorb but have undetectable fluorescence because the spontaneous emission is dominated by their fast non-radiative decay. Yet the detection of their absorption is difficult under a microscope. We use stimulated emission, which competes effectively with the nonradiative decay, to make the chromophores detectable, as a new contrast mechanism for optical microscopy. We demonstrate a variety of applications of stimulated emission microscopy, such as visualizing chromoproteins, non-fluorescent variants of the green fluorescent protein, monitoring lacZ gene expression with a chromogenic reporter, mapping transdermal drug distribu- tions without histological sectioning, and label-free microvascular

  1. Transport behavior of water molecules through two-dimensional nanopores

    SciTech Connect (OSTI)

    Zhu, Chongqin; Li, Hui; Meng, Sheng

    2014-11-14

    Water transport through a two-dimensional nanoporous membrane has attracted increasing attention in recent years thanks to great demands in water purification and desalination applications. However, few studies have been reported on the microscopic mechanisms of water transport through structured nanopores, especially at the atomistic scale. Here we investigate the microstructure of water flow through two-dimensional model graphene membrane containing a variety of nanopores of different size by using molecular dynamics simulations. Our results clearly indicate that the continuum flow transits to discrete molecular flow patterns with decreasing pore sizes. While for pores with a diameter ≥15 Å water flux exhibits a linear dependence on the pore area, a nonlinear relationship between water flux and pore area has been identified for smaller pores. We attribute this deviation from linear behavior to the presence of discrete water flow, which is strongly influenced by the water-membrane interaction and hydrogen bonding between water molecules.

  2. Reaction mechanism studies of unsaturated molecules using photofragment translational spectroscopy

    SciTech Connect (OSTI)

    Longfellow, C.A. |

    1996-05-01

    A number of molecules have been studied using the technique of photofragment translational spectroscopy. In Chapter One a brief introduction to the experimental technique is given. In Chapter Two the infrared multiphoton dissociation (IRMPD) of acetic acid is discussed. Carbon dioxide and methane were observed for the first time as products from dissociation under collisionless conditions. Chapter Three relates an IRMPD experiment of hexafluoropropene. The predominant channel produces CFCF{sub 3} or C{sub 2}F{sub 4} and CF{sub 2}, with the heavier species undergoing further dissociation to two CF{sub 2} fragments. In Chapter Four the ultraviolet (UV) dissociation of hexafluoropropene is investigated. Chapter Five explores the IRMPD of octafluoro-1-butene and octafluoro-2-butene.

  3. Gas phase ion-molecule reactions, spectroscopy and dynamics

    SciTech Connect (OSTI)

    Rinden, E.

    1989-01-01

    The chemical reactivity of nitric oxide anion (NO{sup {minus}}) with a variety of organic neurals at ambient and in argon bath gas has been probed using the flowing afterglow technique. The reactions fall into four main classes: electron transfer, dissociative electron transfer and/or displacement, collisional detachment and clustering. Electron transfer can occur when the neutral reactant possesses a positive electron affinity greater than the electron affinity of NO{center dot}, but does not always do so. Bimolecular substitution at sulfur is shown to occur with dimethyl disulfide, but for other substrates, distinguishing between displacement and dissociative electron transfer is not possible. Collisional detachment is the exclusive reaction channel observed for a few of the molecules examined, and occurs to some extent with many of the neutrals tested. Cluster ion formation between NO{sup {minus}} and a number of the reactant neutrals which possess permanent dipole moments is observed. The collected observations are discussed in the general theory of ion-molecule reactions. Cross sections for vibrational relaxation in small ionic systems (Li{sup +}-H{sub 2},Li{sup +}-D{sub 2}, ArH{sup +}-Ar and ArD{sup +}-Ar) have been calculated numerically using the j{sub z}-conserving coupled states approximation (CSA), and contrasted with cross sections calculated by methods which exclude the effects of attractive forces and/or rotation. Both attractive forces and rotations are found to be extremely important contributors to relaxation in ions; in the Li{sup +}-H{sub 2}/D{sub 2} systems these effects are separable whereas in ArH{sup +}/D{sup +}-Ar they are not. Attractive forces substantially enhance the cross sections at all collision energies and are responsible for the general collisional energy dependence of the cross sections. Molecular rotation is found to enhance cross sections most strongly at low collision energies in each system.

  4. Recent developments with metalloprotease inhibitor class of drug candidates for Botulinum neurotoxins

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kumar, Gyanendra; Swaminathan, Subramanyam

    2015-03-01

    Botulinum Neurotoxins are the most poisonous of all toxins with lethal dose in nanogram quantities. They are also potential biological warfare and bioterrorism agents due to their high toxicity and ease of preparation. On the other hand BoNTs are also being increasingly used for therapeutic and cosmetic purposes, and with that the chances of accidental overdose are increasing. And despite the potential damage they could cause to human health, there are no post-intoxication drugs available so far. But progress is being made in this direction. The crystal structures in native form and bound with substrate peptides have been determined, andmore » these are enabling structure-based drug discovery possible. High throughput assays have also been designed to speed up the screening progress. Substrate-based and small molecule inhibitors have been identified. But turning high affinity inhibitors into clinically viable drug candidates has remained a challenge. We discuss here the latest developments and the future challenges in drug discovery for Botulinum neurotoxins.« less

  5. Recent developments with metalloprotease inhibitor class of drug candidates for Botulinum neurotoxins

    SciTech Connect (OSTI)

    Kumar, Gyanendra; Swaminathan, Subramanyam

    2015-03-01

    Botulinum Neurotoxins are the most poisonous of all toxins with lethal dose in nanogram quantities. They are also potential biological warfare and bioterrorism agents due to their high toxicity and ease of preparation. On the other hand BoNTs are also being increasingly used for therapeutic and cosmetic purposes, and with that the chances of accidental overdose are increasing. And despite the potential damage they could cause to human health, there are no post-intoxication drugs available so far. But progress is being made in this direction. The crystal structures in native form and bound with substrate peptides have been determined, and these are enabling structure-based drug discovery possible. High throughput assays have also been designed to speed up the screening progress. Substrate-based and small molecule inhibitors have been identified. But turning high affinity inhibitors into clinically viable drug candidates has remained a challenge. We discuss here the latest developments and the future challenges in drug discovery for Botulinum neurotoxins.

  6. Method for loading lipid like vesicles with drugs of other chemicals

    DOE Patents [OSTI]

    Mehlhorn, Rolf Joachim

    1998-01-01

    A method for accumulating drugs or other chemicals within synthetic, lipid-like vesicles by means of a pH gradient imposed on the vesicles just prior to use is described. The method is suited for accumulating molecules with basic or acid moieties which are permeable to the vesicles membranes in their uncharged form and for molecules that contain charge moieties that are hydrophobic ions and can therefore cross the vesicle membranes in their charged form. The method is advantageous over prior art methods for encapsulating biologically active materials within vesicles in that is achieves very high degrees of loading with simple procedures that are economical and require little technical expertise, furthermore kits which can be stored for prolonged periods prior to use without impairment of the capacity to achieve drug accumulation are described. A related application of the method consists of using this technology to detoxify animals that have been exposed to poisons with basic, weak acid or hydrophobic charge groups within their molecular structures.

  7. Method for loading lipid like vesicles with drugs of other chemicals

    DOE Patents [OSTI]

    Mehlhorn, R.J.

    1998-06-09

    A method for accumulating drugs or other chemicals within synthetic, lipid-like vesicles by means of a pH gradient imposed on the vesicles just prior to use is described. The method is suited for accumulating molecules with basic or acid moieties which are permeable to the vesicles membranes in their uncharged form and for molecules that contain charge moieties that are hydrophobic ions and can therefore cross the vesicle membranes in their charged form. The method is advantageous over prior art methods for encapsulating biologically active materials within vesicles in that is achieves very high degrees of loading with simple procedures that are economical and require little technical expertise, furthermore kits which can be stored for prolonged periods prior to use without impairment of the capacity to achieve drug accumulation are described. A related application of the method consists of using this technology to detoxify animals that have been exposed to poisons with basic, weak acid or hydrophobic charge groups within their molecular structures. 2 figs.

  8. Oligomycin frames a common drug-binding site in the ATP synthase

    SciTech Connect (OSTI)

    Symersky, Jindrich; Osowski, Daniel; Walters, D. Eric; Mueller, David M.

    2015-12-01

    We report the high-resolution (1.9 {angstrom}) crystal structure of oligomycin bound to the subunit c10 ring of the yeast mitochondrial ATP synthase. Oligomycin binds to the surface of the c10 ring making contact with two neighboring molecules at a position that explains the inhibitory effect on ATP synthesis. The carboxyl side chain of Glu59, which is essential for proton translocation, forms an H-bond with oligomycin via a bridging water molecule but is otherwise shielded from the aqueous environment. The remaining contacts between oligomycin and subunit c are primarily hydrophobic. The amino acid residues that form the oligomycin-binding site are 100% conserved between human and yeast but are widely different from those in bacterial homologs, thus explaining the differential sensitivity to oligomycin. Prior genetics studies suggest that the oligomycin-binding site overlaps with the binding site of other antibiotics, including those effective against Mycobacterium tuberculosis, and thereby frames a common 'drug-binding site.' We anticipate that this drug-binding site will serve as an effective target for new antibiotics developed by rational design.

  9. Ancient Proteins Help Unravel a Modern Cancer Drug's Mechanism

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ancient Proteins Help Unravel a Modern Cancer Drug's Mechanism Ancient Proteins Help Unravel a Modern Cancer Drug's Mechanism Print Tuesday, 23 June 2015 13:00 The cancer drug...

  10. Continuum model for chiral induced spin selectivity in helical molecules

    SciTech Connect (OSTI)

    Medina, Ernesto; Gonzlez-Arraga, Luis A.; Finkelstein-Shapiro, Daniel; Mujica, Vladimiro; Berche, Bertrand

    2015-05-21

    A minimal model is exactly solved for electron spin transport on a helix. Electron transport is assumed to be supported by well oriented p{sub z} type orbitals on base molecules forming a staircase of definite chirality. In a tight binding interpretation, the spin-orbit coupling (SOC) opens up an effective ?{sub z} ? ?{sub z} coupling via interbase p{sub x,y} ? p{sub z} hopping, introducing spin coupled transport. The resulting continuum model spectrum shows two Kramers doublet transport channels with a gap proportional to the SOC. Each doubly degenerate channel satisfies time reversal symmetry; nevertheless, a bias chooses a transport direction and thus selects for spin orientation. The model predicts (i) which spin orientation is selected depending on chirality and bias, (ii) changes in spin preference as a function of input Fermi level and (iii) back-scattering suppression protected by the SO gap. We compute the spin current with a definite helicity and find it to be proportional to the torsion of the chiral structure and the non-adiabatic Aharonov-Anandan phase. To describe room temperature transport, we assume that the total transmission is the result of a product of coherent steps.

  11. Observing a coherent superposition of an atom and a molecule

    SciTech Connect (OSTI)

    Dowling, Mark R. [School of Physical Sciences, University of Queensland, St. Lucia, Queensland 4072 (Australia); Bartlett, Stephen D. [School of Physics, University of Sydney, Sydney, New South Wales 2006 (Australia); Rudolph, Terry [Optics Section, Blackett Laboratory, Imperial College London, London SW7 2BW (United Kingdom); Institute for Mathematical Sciences, Imperial College London, London SW7 2BW (United Kingdom); Spekkens, Robert W. [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB3 0WA (United Kingdom)

    2006-11-15

    We demonstrate that it is possible, in principle, to perform a Ramsey-type interference experiment to exhibit a coherent superposition of a single atom and a diatomic molecule. This gedanken experiment, based on the techniques of Aharonov and Susskind [Phys. Rev. 155, 1428 (1967)], explicitly violates the commonly accepted superselection rule that forbids coherent superpositions of eigenstates of differing atom number. A Bose-Einstein condensate plays the role of a reference frame that allows for coherent operations analogous to Ramsey pulses. We also investigate an analogous gedanken experiment to exhibit a coherent superposition of a single boson and a fermion, violating the commonly accepted superselection rule forbidding coherent superpositions of states of differing particle statistics. In this case, the reference frame is realized by a multimode state of many fermions. This latter case reproduces all of the relevant features of Ramsey interferometry, including Ramsey fringes over many repetitions of the experiment. However, the apparent inability of this proposed experiment to produce well-defined relative phases between two distinct systems each described by a coherent superposition of a boson and a fermion demonstrates that there are additional, outstanding requirements to fully 'lift' the univalence superselection rule.

  12. Single Molecule Kinetics of ENTH Binding to Lipid Membranes

    SciTech Connect (OSTI)

    Rozovsky, Sharon; Forstner, Martin B.; Sondermann, Holger; Groves, Jay T.

    2012-04-03

    Transient recruitment of proteins to membranes is a fundamental mechanism by which the cell exerts spatial and temporal control over proteins’ localization and interactions. Thus, the specificity and the kinetics of peripheral proteins’ membrane residence are an attribute of their function. In this article, we describe the membrane interactions of the interfacial epsin N-terminal homology (ENTH) domain with its target lipid phosphatidylinositol (4,5)-bisphosphate (PtdIns(4,5)P2). The direct visualization and quantification of interactions of single ENTH molecules with supported lipid bilayers is achieved using total internal reflection fluorescence microscopy (TIRFM) with a time resolution of 13 ms. This enables the recording of the kinetic behavior of ENTH interacting with membranes with physiologically relevant concentrations of PtdIns(4,5)P2 despite the low effective binding affinity. Subsequent single fluorophore tracking permits us to build up distributions of residence times and to measure ENTH dissociation rates as a function of membrane composition. In addition, due to the high time resolution, we are able to resolve details of the motion of ENTH associated with a simple, homogeneous membrane. In this case ENTH’s diffusive transport appears to be the result of at least three different diffusion processes.

  13. Spectroscopy, Thermochemistry, and Reactivity of Lanthanide and Actinide Molecules

    SciTech Connect (OSTI)

    Morse, Michael D.; Armentrout, Peter B.

    2012-08-16

    The research undertaken under this grant is described in this document. The document describes progress in the construction of an instrument for recording photodissociation action spectra of mass-selected cryo-cooled cations. The instrument is not yet functional, but we anticipate trapping ions and conducting photodissociation experiments before the end of the year. It also describes resonant two-photon ionization spectra that have been recorded for uranium mononitride (UN) in the visible portion of the spectrum. These experiments are still underway at the present time. Although the spectra are a bit difficult to properly fit, due to upper state perturbations, it appears that the molecule has a ground state with {Omega} = 3.5 and a bond length of approximately 1.76 {angstrom}. Finally, results on the thermochemistry and reactivity of Th{sup +} are presented. In these studies the bond energies of the following bonds have been determined: D{sub 0}(Th{sup +}-2O) = 10.2 {+-} 0.2 eV; D0(Th{sup +}-N) = 6.69 {+-} 0.35 eV; D0(Th{sup +}-O) = 8.40 {+-} 0.28 eV; D{sub 0}(OTh{sup +}-O) = 1.8 {+-} 0.4 eV.

  14. Spin-dependent electron transport in zinc- and manganese-doped adenine molecules

    SciTech Connect (OSTI)

    Simchi, Hamidreza; Esmaeilzadeh, Mahdi Mazidabadi, Hossein

    2014-01-28

    The spin-dependent electron transport properties of zinc- and manganese-doped adenine molecules connected to zigzag graphene leads are studied in the zero bias regime using the non-equilibrium Green's function method. The conductance of the adenine molecule increased and became spin-dependent when a zinc or manganese atom was doped into the molecules. The effects of a transverse electric field on the spin-polarization of the transmitted electrons were investigated and the spin-polarization was controlled by changing the transverse electric field. Under the presence of a transverse electric field, both the zinc- and manganese-doped adenine molecules acted as spin-filters. The maximum spin-polarization of the manganese-doped adenine molecule was greater than the molecule doped with zinc.

  15. Matrix Infrared Spectroscopic and Computational Investigations of Novel Small Uranium Containing Molecules - Final Technical Report

    SciTech Connect (OSTI)

    Andrews, Lester

    2014-10-17

    Direct reactions of f-element uranium, thorium and lanthanide metal atoms were investigated with small molecules. These metal atoms were generated by laser ablation and mixed with the reagent molecules then condensed with noble gases at 4K. The products were analyzed by absorption of infrared light to measure vibrational frequencies which were confirmed by quantum chemical calculations. We have learned more about the reactivity of uranium atoms with common molecules, which will aid in the develolpment of further applications of uranium.

  16. Controlling orbital-selective Kondo effects in a single molecule through

    Office of Scientific and Technical Information (OSTI)

    coordination chemistry (Journal Article) | SciTech Connect Controlling orbital-selective Kondo effects in a single molecule through coordination chemistry Citation Details In-Document Search Title: Controlling orbital-selective Kondo effects in a single molecule through coordination chemistry Iron(II) phthalocyanine (FePc) molecule causes novel Kondo effects derived from the unique electronic structure of multi-spins and multi-orbitals when attached to Au(111). Two unpaired electrons in the

  17. Spontaneous Liver Rupture After Treatment With Drug-Eluting Beads...

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: 62 RADIOLOGY AND NUCLEAR ... DRUGS; BODY; CARCINOMAS; DIGESTIVE SYSTEM; DISEASES; DRUGS; FAILURES; GLANDS; ...

  18. Flow cytometry aids basic cell biology research and drug discovery

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Flow cytometry aids basic cell biology research and drug discovery Flow cytometry aids basic cell biology research and drug discovery Life Technologies Corporation and LANL have ...

  19. Study reveals structure of tuberculosis enzyme, could offer drug...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of tuberculosis enzyme, could offer drug target By Louise Lerner * November 2, 2015 Tweet ... Researchers have been interested in the mycobacterium IMPDH enzyme as a drug target for ...

  20. Topo II: An Enzyme Target for Antibacterial and Cancer Drugs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Topo II: An Enzyme Target for Antibacterial and Cancer Drugs Print The veil has finally ... transcription and replication and is a prime target of antibacterial and anticancer drugs. ...

  1. Ancient Proteins Help Unravel a Modern Cancer Drug's Mechanism

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ancient Proteins Help Unravel a Modern Cancer Drug's Mechanism Print The cancer drug Gleevec is extremely specific, binding and inhibiting only the cancer-causing tyrosine protein...

  2. FACT SHEET ON THE CONSEQUENCES OF A FAILED DRUG TEST

    Office of Environmental Management (EM)

    SHEET ON THE CONSEQUENCES OF A POSITIVE DRUG TEST The Secretary has determined that ... The information below summarizes the consequences of a positive test for drugs for each ...

  3. Food and Drug Administration White Oak Campus Environmental Stewardshi...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Food and Drug Administration White Oak Campus Environmental Stewardship and Cost Savings FEMP ESPC Success Story on water conservation and green energy at the Food and Drug ...

  4. A Small Molecule That Switches a Ubiquitin Ligase From a Processive...

    Office of Scientific and Technical Information (OSTI)

    Title: A Small Molecule That Switches a Ubiquitin Ligase From a Processive to a Distributive Enzymatic Mechanism Authors: Kathman, Stefan G. ; Span, Ingrid ; Smith, Aaron T. ; Xu, ...

  5. Organic Molecule Functionalized Zn3P2 Nanowire Inorganic-Organic...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Organic Molecule Functionalized Zn3P2 Nanowire Inorganic-Organic Hybrid Thermoelectrics Demonstrates self-catalytic schemes for large-scale synthesis of compound semiconductor ...

  6. Small Molecule Adsorption in Open-Site Metal-Organic Frameworks...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Small Molecule Adsorption in Open-Site Metal-Organic Frameworks: A Systematic Density Functional Theory Study for Rational Design Previous Next List Kyuho Lee, Joshua D. Howe,...

  7. Viable Single-Molecule Diodes | U.S. DOE Office of Science (SC...

    Office of Science (SC) Website

    The Impact Individual molecules represent the gold standard for electronics miniaturization, which leads to improved performance, greater utility and lower costs. Summary A ...

  8. THE ORIGIN OF COMPLEX ORGANIC MOLECULES IN PRESTELLAR CORES

    SciTech Connect (OSTI)

    Vastel, C.; Ceccarelli, C.; Lefloch, B.; Bachiller, R.

    2014-11-01

    Complex organic molecules (COMs) have been detected in a variety of environments including cold prestellar cores. Given the low temperatures of these objects, these detections challenge existing models. We report here new observations toward the prestellar core L1544. They are based on an unbiased spectral survey of the 3mm band at the IRAM 30m telescope as part of the Large Program ASAI. The observations allow us to provide a full census of the oxygen-bearing COMs in this source. We detected tricarbon monoxide, methanol, acetaldehyde, formic acid, ketene, and propyne with abundances varying from 5 10{sup 11} to 6 10{sup 9}. The non-LTE analysis of the methanol lines shows that they are likely emitted at the border of the core at a radius of ?8000 AU, where T ? 10K and n {sub H{sub 2}} ?2 10{sup 4}cm{sup 3}. Previous works have shown that water vapor is enhanced in the same region because of the photodesorption of water ices. We propose that a non-thermal desorption mechanism is also responsible for the observed emission of methanol and COMs from the same layer. The desorbed oxygen and a small amount of desorbed methanol and ethene are enough to reproduce the abundances of tricarbon monoxide, methanol, acetaldehyde, and ketene measured in L1544. These new findings open the possibility that COMs in prestellar cores originate in a similar outer layer rather than in the dense inner cores, as previously assumed, and that their formation is driven by the non-thermally desorbed species.

  9. Inorganic-Organic Molecules and Solids with Nanometer-Sized Pores

    SciTech Connect (OSTI)

    Maverick, Andrew W

    2011-12-17

    We are constructing porous inorganic-organic hybrid molecules and solids, many of which contain coordinatively unsaturated metal centers. In this work, we use multifunctional ²-diketone ligands as building blocks to prepare extended-solid and molecular porous materials that are capable of reacting with a variety of guest molecules.

  10. Electrochemical detection of single molecules using abiotic nanopores having electrically tunable dimensions

    DOE Patents [OSTI]

    Sansinena, Jose-Maria; Redondo, Antonio; Olazabal, Virginia; Hoffbauer, Mark A.; Akhadov, Elshan A.

    2009-12-29

    A barrier structure for use in an electrochemical stochastic membrane sensor for single molecule detection. The sensor is based upon inorganic nanopores having electrically tunable dimensions. The inorganic nanopores are formed from inorganic materials and an electrically conductive polymer. Methods of making the barrier structure and sensing single molecules using the barrier structure are also described.

  11. Organic molecules deposited on graphene: A computational investigation of self-assembly and electronic structure

    SciTech Connect (OSTI)

    Oliveira, I. S. S. de; Miwa, R. H.

    2015-01-28

    We use ab initio simulations to investigate the adsorption and the self-assembly processes of tetracyanoquinodimethane (TCNQ), tetrafluoro-tetracyanoquinodimethane (F4-TCNQ), and tetrasodium 1,3,6,8-pyrenetetrasulfonic acid (TPA) on the graphene surface. We find that there are no chemical bonds at the moleculegraphene interface, even at the presence of grain boundaries on the graphene surface. The molecules bond to graphene through van der Waals interactions. In addition to the moleculegraphene interaction, we performed a detailed study of the role played by the (lateral) moleculemolecule interaction in the formation of the, experimentally verified, self-assembled layers of TCNQ and TPA on graphene. Regarding the electronic properties, we calculate the electronic charge transfer from the graphene sheet to the TCNQ and F4-TCNQ molecules, leading to a p-doping of graphene. Meanwhile, such charge transfer is reduced by an order of magnitude for TPA molecules on graphene. In this case, it is not expected a significant doping process upon the formation of self-assembled layer of TPA molecules on the graphene sheet.

  12. Group specific internal standard technology (GSIST) for simultaneous identification and quantification of small molecules

    DOE Patents [OSTI]

    Adamec, Jiri; Yang, Wen-Chu; Regnier, Fred E

    2014-01-14

    Reagents and methods are provided that permit simultaneous analysis of multiple diverse small molecule analytes present in a complex mixture. Samples are labeled with chemically identical but isotopically distince forms of the labeling reagent, and analyzed using mass spectrometry. A single reagent simultaneously derivatizes multiple small molecule analytes having different reactive functional groups.

  13. Method and apparatus for passive optical dosimeter comprising caged dye molecules

    DOE Patents [OSTI]

    Sandison, David R.

    2001-07-03

    A new class of ultraviolet dosimeters is made possible by exposing caged dye molecules, which generate a dye molecule on exposure to ultraviolet radiation, to an exterior environment. Applications include sunburn monitors, characterizing the UV exposure history of UV-sensitive materials, especially including structural plastics, and use in disposable `one-use` optical equipment, especially medical devices.

  14. Electro fluido dynamic techniques to design instructive biomaterials for tissue engineering and drug delivery

    SciTech Connect (OSTI)

    Guarino, Vincenzo Altobelli, Rosaria; Cirillo, Valentina; Ambrosio, Luigi

    2015-12-17

    A large variety of processes and tools is continuously investigated to discover new solutions to design instructive materials with controlled chemical, physical and biological properties for tissue engineering and drug delivery. Among them, electro fluido dynamic techniques (EFDTs) are emerging as an interesting strategy, based on highly flexible and low-cost processes, to revisit old biomaterial’s manufacturing approach by utilizing electrostatic forces as the driving force for the fabrication of 3D architectures with controlled physical and chemical functionalities to guide in vitro and in vivo cell activities. By a rational selection of polymer solution properties and process conditions, EFDTs allow to produce fibres and/or particles at micro and/or nanometric size scale which may be variously assembled by tailored experimental setups, thus giving the chance to generate a plethora of different 3D devices able to incorporate biopolymers (i.e., proteins, polysaccharides) or active molecules (e.g., drugs) for different applications. Here, we focus on the optimization of basic EFDTs - namely electrospinning, electrospraying and electrodynamic atomization - to develop active platforms (i.e., monocomponent, protein and drug loaded scaffolds and µ-scaffolds) made of synthetic (PCL, PLGA) or natural (chitosan, alginate) polymers. In particular, we investigate how to set materials and process parameters to impart specific morphological, biochemical or physical cues to trigger all the fundamental cell–biomaterial and cell– cell cross-talking elicited during regenerative processes, in order to reproduce the complex microenvironment of native or pathological tissues.

  15. Modeling molecule-plasmon interactions using quantized radiation fields within time-dependent electronic structure theory

    SciTech Connect (OSTI)

    Nascimento, Daniel R.; DePrince, A. Eugene

    2015-12-07

    We present a combined cavity quantum electrodynamics/ab initio electronic structure approach for simulating plasmon-molecule interactions in the time domain. The simple Jaynes-Cummings-type model Hamiltonian typically utilized in such simulations is replaced with one in which the molecular component of the coupled system is treated in a fully ab initio way, resulting in a computationally efficient description of general plasmon-molecule interactions. Mutual polarization effects are easily incorporated within a standard ground-state Hartree-Fock computation, and time-dependent simulations carry the same formal computational scaling as real-time time-dependent Hartree-Fock theory. As a proof of principle, we apply this generalized method to the emergence of a Fano-like resonance in coupled molecule-plasmon systems; this feature is quite sensitive to the nanoparticle-molecule separation and the orientation of the molecule relative to the polarization of the external electric field.

  16. Secretary Bodman's Memorandum Regarding Drug Testing at DOE

    Broader source: Energy.gov [DOE]

    Decisions regarding drug testing for Department of Energy positions that require access authorizations (Security Clearances)

  17. Resonance reactions and enhancement of weak interactions in collisions of cold molecules

    SciTech Connect (OSTI)

    Flambaum, V. V.; Ginges, J. S. M. [School of Physics, University of New South Wales, Sydney 2052 (Australia)

    2006-08-15

    With the creation of ultracold atoms and molecules, a new type of chemistry - 'resonance' chemistry - emerges: chemical reactions can occur when the energy of colliding atoms and molecules matches a bound state of the combined molecule (Feshbach resonance). This chemistry is rather similar to reactions that take place in nuclei at low energies. In this paper we suggest some problems for future experimental and theoretical work related to the resonance chemistry of ultracold molecules. Molecular Bose-Einstein condensates are particularly interesting because in this system collisions and chemical reactions are extremely sensitive to weak fields; also, a preferred reaction channel may be enhanced due to a finite number of final states. The sensitivity to weak fields arises due to the high density of narrow compound resonances and the macroscopic number of molecules with kinetic energy E=0 (in the ground state of a mean-field potential). The high sensitivity to the magnetic field may be used to measure the distribution of energy intervals, widths, and magnetic moments of compound resonances and study the onset of quantum chaos. A difference in the production rate of right-handed and left-handed chiral molecules may be produced by external electric E and magnetic B fields and the finite width {gamma} of the resonance (correlation {gamma}E{center_dot}B). The same effect may be produced by the parity-violating energy difference in chiral molecules.

  18. Growth of Ammonium Bisulfate Clusters by Adsorption of Oxygenated Organic Molecules

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    DePalma, Joseph W.; Wang, Jian; Wexler, Anthony S.; Johnston, Murray V.

    2015-10-21

    Quantum chemical calculations were employed to model the interactions of the [(NH4+)4(HSO4-)4] ammonium bisulfate cluster with one or more molecular products of monoterpene oxidation. A strong interaction was found between the bisulfate ion of the cluster and a carboxylic acid, aldehyde or ketone functionality of the organic molecule. Free energies of adsorption for carboxylic acids were in the -70 to -73 kJ/mol range, while those for aldehydes and ketones were in the -46 to -50 kJ/mol range. These values suggest that a small ambient ammonium bisulfate cluster, such as the [(NH4+)4(SO4-)4] cluster, is able to adsorb an oxygenated organic molecule.more » Although adsorption of the first molecule is highly favorable, adsorption of subsequent molecules is not, suggesting that sustained uptake of organic molecules does not occur, and thus is not a pathway for continuing growth of the cluster. This result is consistent with ambient measurements showing that particles below ~1 nm grow slowly, while those above 1 nm grow at an increasing rate presumably due to a lower surface energy barrier enabling the uptake of organic molecules. This work provides insight into the molecular level interactions which affect sustained cluster growth by uptake of organic molecules.« less

  19. Growth of Ammonium Bisulfate Clusters by Adsorption of Oxygenated Organic Molecules

    SciTech Connect (OSTI)

    DePalma, Joseph W.; Wang, Jian; Wexler, Anthony S.; Johnston, Murray V.

    2015-10-21

    Quantum chemical calculations were employed to model the interactions of the [(NH4+)4(HSO4-)4] ammonium bisulfate cluster with one or more molecular products of monoterpene oxidation. A strong interaction was found between the bisulfate ion of the cluster and a carboxylic acid, aldehyde or ketone functionality of the organic molecule. Free energies of adsorption for carboxylic acids were in the -70 to -73 kJ/mol range, while those for aldehydes and ketones were in the -46 to -50 kJ/mol range. These values suggest that a small ambient ammonium bisulfate cluster, such as the [(NH4+)4(SO4-)4] cluster, is able to adsorb an oxygenated organic molecule. Although adsorption of the first molecule is highly favorable, adsorption of subsequent molecules is not, suggesting that sustained uptake of organic molecules does not occur, and thus is not a pathway for continuing growth of the cluster. This result is consistent with ambient measurements showing that particles below ~1 nm grow slowly, while those above 1 nm grow at an increasing rate presumably due to a lower surface energy barrier enabling the uptake of organic molecules. This work provides insight into the molecular level interactions which affect sustained cluster growth by uptake of organic molecules.

  20. Controlling the optical dipole force for molecules with field-induced alignment

    SciTech Connect (OSTI)

    Purcell, S. M.; Barker, P. F.

    2010-09-15

    We measure the role of field-induced alignment on the dipole force for molecules using a single focused nonresonant laser beam. We show that through the alignment process we can modify the effective polarizability by field polarization and thus control the center-of-mass motion of the molecule. We observe a maximum change of 20% in the dipole force on CS{sub 2} molecules when changing from linearly to circularly polarized light. Additionally, the effect of the dipole force on different vibrational states is also studied.

  1. Mechanism of Angular Momentum Exchange between Molecules and Laguerre-Gaussian Beams

    SciTech Connect (OSTI)

    Alexandrescu, Adrian; Cojoc, Dan; Fabrizio, Enzo Di

    2006-06-23

    We derive the interaction Hamiltonian between a diatomic molecule and a Laguerre-Gaussian beam under the assumption of a small spread of the center of mass wave function of the molecule in comparison with the beam waist. Considering the dynamical variables of the center of mass, vibrational, rotational, and electronic motion, we show that, within the electronic dipole approximation, the orbital angular momentum of the field couples with the rotational and electronic motion. The changes in the transition probabilities and selection rules induced by the field orbital angular momentum and the applicability of the derived interaction mechanisms for polyatomic molecules are discussed.

  2. Reconstruction of the Electron Density of Molecules with Single-Axis Alignment

    SciTech Connect (OSTI)

    Starodub, Dmitri

    2011-08-12

    Diffraction from the individual molecules of a molecular beam, aligned parallel to a single axis by a strong electric field or other means, has been proposed as a means of structure determination of individual molecules. As in fiber diffraction, all the information extractable is contained in a diffraction pattern from incidence of the diffracting beam normal to the molecular alignment axis. We present two methods of structure solution for this case. One is based on the iterative projection algorithms for phase retrieval applied to the coefficients of the cylindrical harmonic expansion of the molecular electron density. Another is the holographic approach utilizing presence of the strongly scattering reference atom for a specific molecule.

  3. Artificial molecules that switch "handedness" at light-speed

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Artificial molecules that switch "handedness" Artificial molecules that switch "handedness" at light-speed Researchers create the first artificial molecules whose chirality can be rapidly switched from a right-handed to a left-handed orientation with a beam of light. July 10, 2012 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience,

  4. Dynamics of copper-phthalocyanine molecules on Au/Ge(001)

    SciTech Connect (OSTI)

    Sotthewes, K.; Heimbuch, R.; Zandvliet, H. J. W.

    2015-10-07

    Spatially resolved current-time scanning tunneling spectroscopy combined with current-distance spectroscopy has been used to characterize the dynamic behavior of copper-phthalocyanine (CuPc) molecules adsorbed on a Au-modified Ge(001) surface. The analyzed CuPc molecules are adsorbed in a “molecular bridge” configuration, where two benzopyrrole groups (lobes) are connected to a Au-induced nanowire, whereas the other two lobes are connected to the adjacent nanowire. Three types of lobe configurations are found: a bright lobe, a dim lobe, and a fuzzy lobe. The dim and fuzzy lobes exhibit a well-defined switching behavior between two discrete levels, while the bright lobe shows a broad oscillation band. The observed dynamic behavior is induced by electrons that are injected into the LUMO+1 orbital of the CuPc molecule. By precisely adjusting the tip-molecule distance, the switching frequency of the lobes can be tuned accurately.

  5. From Artificial Atoms to Nanocrystal Molecules: Preparation and Properties of More Complex Nanostructures

    SciTech Connect (OSTI)

    Choi, Charina L; Alivisatos, A Paul

    2009-10-20

    Quantum dots, which have found widespread use in fields such as biomedicine, photovoltaics, and electronics, are often called artificial atoms due to their size-dependent physical properties. Here this analogy is extended to consider artificial nanocrystal molecules, formed from well-defined groupings of plasmonically or electronically coupled single nanocrystals. Just as a hydrogen molecule has properties distinct from two uncoupled hydrogen atoms, a key feature of nanocrystal molecules is that they exhibit properties altered from those of the component nanoparticles due to coupling. The nature of the coupling between nanocrystal atoms and its response to vibrations and deformations of the nanocrystal molecule bonds are of particular interest. We discuss synthetic approaches, predicted and observed physical properties, and prospects and challenges toward this new class of materials.

  6. Atomistic Simulation of Nafion Membrane: 2. Dynamics of Water Molecules and Hydronium Ions

    SciTech Connect (OSTI)

    Devanathan, Ram; Venkatnathan, Arun; Dupuis, Michel

    2007-10-20

    We have performed a detailed and comprehensive analysis of the dynamics of water molecules and hydronium ions in hydrated Nafion using classical molecular dynamics simulations with the DREIDING force field. In addition to calculating diffusion coefficients as a function of hydration level, we have also determined mean residence time of H2O molecules and H3O+ ions in the first solvation shell of SO3- groups. The diffusion coefficient of H2O molecules increases with increasing hydration level and is in good agreement with experiment. The mean residence time of H2O molecules decreases with increasing membrane hydration from 1 ns at a low hydration level to 75 ps at the highest hydration level studied. These dynamical changes are related to the changes in membrane nanostructure reported in the first part of this work. Our results provide insights into slow proton dynamics observed in neutron scattering experiments and are consistent with the Gebel model of Nafion structure.

  7. Ionization of oriented carbonyl sulfide molecules by intense circularly polarized laser pulses

    SciTech Connect (OSTI)

    Dimitrovski, Darko; Abu-samha, Mahmoud; Madsen, Lars Bojer; Filsinger, Frank; Meijer, Gerard; Kuepper, Jochen [Lundbeck Foundation Theoretical Center for Quantum System Research, Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C (Denmark); Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin (Germany); Holmegaard, Lotte; Kalhoej, Line [Department of Chemistry, Aarhus University, DK-8000 Aarhus C (Denmark); Nielsen, Jens H. [Department of Physics, Aarhus University, DK-8000 Aarhus C (Denmark); Stapelfeldt, Henrik [Department of Chemistry, Aarhus University, DK-8000 Aarhus C (Denmark); Interdisciplinary Nanoscience Center (iNANO), Aarhus University, DK-8000 Aarhus C (Denmark)

    2011-02-15

    We present combined experimental and theoretical results on strong-field ionization of oriented carbonyl sulfide molecules by circularly polarized laser pulses. The obtained molecular frame photoelectron angular distributions show pronounced asymmetries perpendicular to the direction of the molecular electric dipole moment. These findings are explained by a tunneling model invoking the laser-induced Stark shifts associated with the dipoles and polarizabilities of the molecule and its unrelaxed cation. The focus of the present article is to understand the strong-field ionization of one-dimensionally-oriented polar molecules, in particular asymmetries in the emission direction of the photoelectrons. In the following article [Phys. Rev. A 83, 023406 (2011)] the focus is to understand strong-field ionization from three-dimensionally-oriented asymmetric top molecules, in particular the suppression of electron emission in nodal planes of molecular orbitals.

  8. Complete solution of electronic excitation and ionization in electron-hydrogen molecule scattering

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zammit, Mark C.; Savage, Jeremy S.; Fursa, Dmitry V.; Bray, Igor

    2016-06-01

    The convergent close-coupling method has been used to solve the electron-hydrogen molecule scattering problem in the fixed-nuclei approximation. Excellent agreement with experiment is found for the grand total, elastic, electronic-excitation, and total ionization cross sections from the very low to the very high energies. This shows that for the electronic degrees of freedom the method provides a complete treatment of electron scattering on molecules as it does for atoms.

  9. Tracing the structure of asymmetric molecules from high-order harmonic generation

    SciTech Connect (OSTI)

    Chen Yanjun; Zhang, Bing

    2011-11-15

    We investigate high-order harmonic generation (HHG) from asymmetric molecules exposed to intense laser fields. We show that the emissions of odd and even harmonics depend differently on the orientation angle, the internuclear distance, as well as the effective charge. This difference mainly comes from different roles of intramolecular interference in the HHG of odd and even harmonics. These roles map the structure of the asymmetric molecule to the odd vs even HHG spectra.

  10. Unmasking the Molecule | U.S. DOE Office of Science (SC)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Unmasking the Molecule Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic Energy Sciences Advisory Committee (BESAC) Community Resources Contact Information Basic Energy Sciences U.S. Department of Energy SC-22/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3081 F: (301) 903-6594 E: Email Us More Information » 08.07.16 Unmasking the Molecule Researchers reveal the structure of individual