Sample records for pentane chemistry industries

  1. 77 FR 43131 - Designation of the Center for Innovation and Technology Cooperation (CITC), Pentane Chemistry...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-23

    ... Cooperation (CITC), Pentane Chemistry Industries (PCI), and Hossein Tanideh Pursuant to Executive Order 13382... (CITC), Pentane Chemistry Industries (PCI), and Hossein Tanideh Pursuant to E.O. 13382. SUMMARY... Cooperation (CITC), Pentane Chemistry Industries (PCI), and Hossein Tanideh, have engaged, or attempted to...

  2. 78 FR 13142 - Designation of the Center for Innovation and Technology Cooperation (CITC), Pentane Chemistry...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-26

    ... Cooperation (CITC), Pentane Chemistry Industries (PCI), and Hossein Tanideh Pursuant to Executive Order 13382... (CITC), Pentane Chemistry Industries (PCI), and Hossein Tanideh Pursuant to E.O. 13382. SUMMARY... Cooperation (CITC), Pentane Chemistry Industries (PCI), and Hossein Tanideh, have engaged, or attempted to...

  3. Changes in Atmospheric Butanes and Pentanes and Their Isomeric Ratios in the Continental United States

    NASA Astrophysics Data System (ADS)

    Rossabi, Sam; Helmig, Detlev

    2018-04-01

    Nonmethane hydrocarbons have been used as tracers in research on emissions and atmospheric oxidation chemistry. This research investigates source region mixing ratio trends of the nonmethane hydrocarbons i-butane, n-butane, i-pentane, and n-pentane, and the (i/n) isomeric ratios of these compounds between 2001 and 2015. Data collected at Photochemical Assessment Monitoring Stations, mandated by the U.S. Environmental Protection Agency in ozone nonattainment areas, and data collected at Global Greenhouse Gas Reference Network sites within the National Oceanic and Atmospheric Administration network, and analyzed at the Institute of Arctic and Alpine Research at the University of Colorado-Boulder, were examined. Among all considered species, linear regression analyses on concentration time series had negative slopes at 81% of sites, indicating predominantly declining butane and pentane atmospheric concentrations. Mostly negative slopes (78% of sites) were found for the (i/n) butane and pentane isomeric ratios, including all six and seven statistically significant (i/n) butane and pentane trends, respectively. Over the 15 year investigation period and averaged over all sites, total relative changes were 30 and 45% for the (i/n) ratios of butanes and pentanes, respectively, with a relative increase in the prominence of the n-isomers. Most likely causes include changing isomeric ratios in gasoline sector emissions, and increasing influence of oil and natural gas industry emissions. Changes in concentrations and isomeric ratios depend on proximity of contributing emission sources to measurement sites.

  4. Analysis of Non-Methane Hydrocarbon Data from 2004-2016 in a Subtropical Area close to the Gulf of Mexico

    NASA Astrophysics Data System (ADS)

    Rappenglueck, B.

    2017-12-01

    Speciated C2-C11 non-methane hydrocarbons (NMHC) have been measured online on an hourly basis at Lake Jackson/TX close to the Gulf of Mexico. Altogether 48 NMHCs along with NO, NO2, NOx, O3 have been collected continuously from January 2004-December 2016 under the auspices of the Texas Commission on Environmental Quality. Data was screened for background conditions representing marine wind sectors. The data set represents a combination of marine air masses mixed with local biogenic emissions. The data analysis addresses photochemical processing of air masses as reflected in the relationship of ln(n-butane/ethane) vs. ln(propane/ethane) and ln(i-butane/ethane) vs. ln(n-butane/ethane). In addition, key NMHC relationships for radical chemistry, e.g. i-butane vs n-butane for OH and Cl chemistry and i-pentane vs. n-pentane for NO3 chemistry, are discussed. Seasonal analysis revealed a clear trend with maximum NMHC mixing ratios in winter time and lowest mixing ratios in summer reflecting the impact of photochemical processes in summer. Propene equivalents were highest during summertime, with significant contributions from alkenes, including isoprene. The relation of propane/ethane vs ethane indicates seasonal variation with lowest values (i.e. most aged air masses) in winter.

  5. A time-accurate algorithm for chemical non-equilibrium viscous flows at all speeds

    NASA Technical Reports Server (NTRS)

    Shuen, J.-S.; Chen, K.-H.; Choi, Y.

    1992-01-01

    A time-accurate, coupled solution procedure is described for the chemical nonequilibrium Navier-Stokes equations over a wide range of Mach numbers. This method employs the strong conservation form of the governing equations, but uses primitive variables as unknowns. Real gas properties and equilibrium chemistry are considered. Numerical tests include steady convergent-divergent nozzle flows with air dissociation/recombination chemistry, dump combustor flows with n-pentane-air chemistry, nonreacting flow in a model double annular combustor, and nonreacting unsteady driven cavity flows. Numerical results for both the steady and unsteady flows demonstrate the efficiency and robustness of the present algorithm for Mach numbers ranging from the incompressible limit to supersonic speeds.

  6. A coupled implicit method for chemical non-equilibrium flows at all speeds

    NASA Technical Reports Server (NTRS)

    Shuen, Jian-Shun; Chen, Kuo-Huey; Choi, Yunho

    1993-01-01

    The present time-accurate coupled-solution procedure addresses the chemical nonequilibrium Navier-Stokes equations over a wide Mach-number range uses, in conjunction with the strong conservation form of the governing equations, five unknown primitive variables. The numerical tests undertaken address steady convergent-divergent nozzle flows with air dissociation/recombination, dump combustor flows with n-pentane/air chemistry, and unsteady nonreacting cavity flows.

  7. Diurnal and seasonal variation of various carbon fluxes from an urban tower platform in Houston, TX

    NASA Astrophysics Data System (ADS)

    Schade, G. W.; Werner, N.; Hale, M. C.

    2013-12-01

    We measured carbon fluxes (CO2, CO, VOCs) from a tall lattice tower in Houston between 2007 and 2009, and 2011-2013. We present results from various analyses of (i) anthropogenic and biogenic CO2 fluxes using a quadrant segregation technique, (ii) seasonal and multi-year changes of CO fluxes as related to car traffic and industrial sources, and (iii) the accuracy of, and usefulness of a bulk flux footprint model to quantify pentane emissions form a distant source in comparison to permitted emission levels. Segregated and net anthropogenic CO2 fluxes were dominated by car traffic but industrial sources were identified as well. Emissions sank to minimal levels after hurricane Ike had passed over Houston, causing a traffic shutdown and lower population density. Segregated biogenic fluxes showed a clear seasonal variation with photosynthetic activity between April and November, and large effects of the 2011 Texas drought due to negligible irrigation in the study area. Carbon monoxide fluxes, measured via a flux gradient technique, are even stronger dominated by car traffic than CO2 fluxes and serve as a traffic tracer. Our data show a continued drop in emissions over time, seasonal changes with higher emissions during winter, and local influences due to industrial emissions. Lastly, we present the results of a tracer release study and a single point source quantification to test a bulk footprint model in this complex urban area. Known releases of volatile acetone and MEK were compered to measured fluxes using a REA-GC-FID system, and permit emissions of pentane from a foam plastics manufacturing facility were compared to measured pentane fluxes. Both comparisons reveal a surprisingly accurate performance of the footprint model within a factor of 2.

  8. 24 CFR Appendix I to Subpart C of... - Specific Hazardous Substances

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Ketone Naptha Pentane Propylene Oxide Toluene Vinyl Acetate Xylene Hazardous Gases Acetaldehyde Butadiene Butane Ethene Ethylene Ethylene Oxide Hydrogen Liquefied Natural Gas (LNG) Liquefied Petroleum Gas (LPG... Commercial/Industrial Facilities,” by Rolf Jensen and Associates, Inc., April 1982) [49 FR 5105, Feb. 10...

  9. Niosh analytical methods for Set G

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1976-12-01

    Industrial Hygiene sampling and analytical monitoring methods validated under the joint NIOSH/OSHA Standards Completion Program for Set G are contained herein. Monitoring methods for the following compounds are included: butadiene, heptane, ketene, methyl cyclohexane, octachloronaphthalene, pentachloronaphthalene, petroleum distillates, propylene dichloride, turpentine, dioxane, hexane, LPG, naphtha(coal tar), octane, pentane, propane, and stoddard solvent.

  10. Adsorption and separation of n/iso-pentane on zeolites: A GCMC study.

    PubMed

    Fu, Hui; Qin, Hansong; Wang, Yajun; Liu, Yibin; Yang, Chaohe; Shan, Honghong

    2018-03-01

    Separation of branched chain hydrocarbons and straight chain hydrocarbons is very important in the isomerization process. Grand canonical ensemble Monte Carlo simulations were used to investigate the adsorption and separation of iso-pentane and n-pentane in four types of zeolites: MWW, BOG, MFI, and LTA. The computation of the pure components indicates that the adsorption capacity is affected by physical properties of zeolite, like pore size and structures, and isosteric heat. In BOG, MFI and LTA, the amount of adsorption of n-pentane is higher than iso-pentane, while the phenomenon is contrary in MWW. For a given zeolite, a stronger adsorption heat corresponds to a higher loading. In the binary mixture simulations, the separation capacity of n-and iso-pentane increases with the elevated pressure and the increasing iso-pentane composition. The adsorption mechanism and competition process have been examined. Preferential adsorption contributions prevail at low pressure, however, the size effect becomes important with the increasing pressure, and the relatively smaller n-pentane gradually competes successfully in binary adsorption. Among these zeolites, MFI has the best separation performance due to its high shape selectivity. This work helps to better understand the adsorption and separation performance of n- and iso-pentane in different zeolites and explain the relationship between zeolite structures and adsorption performance. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Anesthetic synergy between two n-alkanes.

    PubMed

    Brosnan, Robert J; Fukushima, Fabíola B; Pham, Trung L

    2017-05-01

    N-butane and n-pentane can both produce general anesthesia. Both compounds potentiate γ-aminobutyric acid type A (GABA A ) receptor function, but only butane inhibits N-methyl-d-aspartate (NMDA) receptors. It was hypothesized that butane and pentane would exhibit anesthetic synergy due to their different actions on ligand-gated ion channels. Prospective experimental study. A total of four Xenopus laevis frogs and 43 Sprague-Dawley rats. Alkane concentrations for all studies were determined via gas chromatography. Using a Xenopus oocyte expression model, standard two-electrode voltage clamp techniques were used to measure NMDA and GABA A receptor responses in vitro as a function of butane and pentane concentrations relevant to anesthesia. The minimum alveolar concentrations (MAC) of butane and pentane were measured separately in rats, and then pentane MAC was measured during coadministration of 0.25, 0.50 or 0.75 times MAC of butane. An isobole with 95% confidence intervals was constructed using regression analysis. A sum of butane and pentane that was statistically less than the lower-end confidence bound isobole indicated a synergistic interaction. Both butane and pentane dose-dependently potentiated GABA A receptor currents over the study concentration range. Butane dose-dependently inhibited NMDA receptor currents, but pentane did not modulate NMDA receptors. Butane and pentane MAC in rats was 39.4±0.7 and 13.7±0.4 %, respectively. A small but significant (p<0.03) synergistic anesthetic effect with pentane was observed during administration of either 0.50 or 0.75×MAC butane. Butane and pentane show synergistic anesthetic effects in vivo consistent with their different in vitro receptor effects. Findings support the relevance of NMDA receptors in mediating anesthetic actions for some, but not all, inhaled agents. Copyright © 2017 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.

  12. Ethane and n-pentane in exhaled breath are biomarkers of exposure not effect.

    PubMed

    Gorham, Katrine A; Sulbaek Andersen, Mads P; Meinardi, Simone; Delfino, Ralph J; Staimer, Norbert; Tjoa, Thomas; Rowland, F Sherwood; Blake, Donald R

    2009-02-01

    The relationship of exhaled ethane and n-pentane to exhaled NO, carbonylated proteins, and indoor/outdoor atmospheric pollutants were examined in order to evaluate ethane and n-pentane as potential markers of airway inflammation and/or oxidative stress. Exhaled NO and carbonylated proteins were found to have no significant associations with either ethane (p = 0.96 and p = 0.81, respectively) or n-pentane (p = 0.44 and 0.28, respectively) when outliers were included. In the case where outliers were removed n-pentane was found to be inversely associated with carbonylated proteins. Exhaled hydrocarbons adjusted for indoor hydrocarbon concentrations were instead found to be positively associated with air pollutants (NO, NO(2) and CO), suggesting pollutant exposure is driving exhaled hydrocarbon concentrations. Given these findings, ethane and n-pentane do not appear to be markers of airway inflammation or oxidative stress.

  13. Ethane and n-pentane in exhaled breath are biomarkers of exposure not effect

    PubMed Central

    Gorham, Katrine A.; Sulbaek Andersen, Mads P.; Meinardi, Simone; Delfino, Ralph J.; Staimer, Norbert; Tjoa, Thomas; Rowland, F. Sherwood; Blake, Donald R.

    2013-01-01

    The relationship of exhaled ethane and n-pentane to exhaled NO, carbonylated proteins, and indoor/outdoor atmospheric pollutants were examined in order to evaluate ethane and n-pentane as potential markers of airway inflammation and/or oxidative stress. Exhaled NO and carbonylated proteins were found to have no significant associations with either ethane (p = 0.96 and p = 0.81, respectively) or n-pentane (p = 0.44 and 0.28, respectively) when outliers were included. In the case where outliers were removed n-pentane was found to be inversely associated with carbonylated proteins. Exhaled hydrocarbons adjusted for indoor hydrocarbon concentrations were instead found to be positively associated with air pollutants (NO, NO2 and CO), suggesting pollutant exposure is driving exhaled hydrocarbon concentrations. Given these find-ings, ethane and n-pentane do not appear to be markers of airway inflammation or oxidative stress. PMID:19283520

  14. Levitation effect in zeolites: Quasielastic neutron scattering and molecular dynamics study of pentane isomers in zeolite NaY.

    PubMed

    Borah, Bhaskar J; Jobic, H; Yashonath, S

    2010-04-14

    We report the quasielastic neutron scattering (QENS) and molecular dynamics (MD) investigations into diffusion of pentane isomers in zeolite NaY. The molecular cross section perpendicular to the long molecular axis varies for the three isomers while the mass and the isomer-zeolite interaction remains essentially unchanged. Both QENS and MD results show that the branched isomers neopentane and isopentane have higher self-diffusivities as compared with n-pentane at 300 K in NaY zeolite. This result provides direct experimental evidence for the existence of nonmonotonic, anomalous dependence of self-diffusivity on molecular diameter known as the levitation effect. The energetic barrier at the bottleneck derived from MD simulations exists for n-pentane which lies in the linear regime while no such barrier is seen for neopentane which is located clearly in the anomalous regime. Activation energy is in the order E(a)(n-pentane)>E(a)(isopentane)>E(a)(neopentane) consistent with the predictions of the levitation effect. In the liquid phase, it is seen that D(n-pentane)>D(isopentane)>D(neopentane) and E(a)(n-pentane)

  15. Levitation effect in zeolites: Quasielastic neutron scattering and molecular dynamics study of pentane isomers in zeolite NaY

    NASA Astrophysics Data System (ADS)

    Borah, Bhaskar J.; Jobic, H.; Yashonath, S.

    2010-04-01

    We report the quasielastic neutron scattering (QENS) and molecular dynamics (MD) investigations into diffusion of pentane isomers in zeolite NaY. The molecular cross section perpendicular to the long molecular axis varies for the three isomers while the mass and the isomer-zeolite interaction remains essentially unchanged. Both QENS and MD results show that the branched isomers neopentane and isopentane have higher self-diffusivities as compared with n-pentane at 300 K in NaY zeolite. This result provides direct experimental evidence for the existence of nonmonotonic, anomalous dependence of self-diffusivity on molecular diameter known as the levitation effect. The energetic barrier at the bottleneck derived from MD simulations exists for n-pentane which lies in the linear regime while no such barrier is seen for neopentane which is located clearly in the anomalous regime. Activation energy is in the order Ea(n-pentane)>Ea(isopentane)>Ea(neopentane) consistent with the predictions of the levitation effect. In the liquid phase, it is seen that D(n-pentane)>D(isopentane)>D(neopentane) and Ea(n-pentane)

  16. Adsorption of normal pentane on the surface of rutile. Experimental results and simulations.

    PubMed

    Rakhmatkariev, G U; Carvalho, A J Palace; Ramalho, J P Prates

    2007-07-03

    Adsorption isotherms and differential heats of normal pentane adsorption on microcrystalline rutile were measured at 303 K. The heat of adsorption of n-pentane on rutile at zero occupancy is 64 kJ/mol. The differential heats have three descending segments, corresponding to the adsorption of n-pentane on three types of surfaces. At low coverage (first segment), the adsorption is restricted to the rows A of the (110) faces along the 5-fold coordinatively unsaturated (cus) Ti(4+) ions with differential heat showing a linear decrease with increasing occupancy. The second segment is attributed to bonding with atoms of the rows along the remaining faces exposed, (101) and (100). The third segment is related to a multilayer adsorption. The mean molar adsorption entropy of n-pentane is ca. -25 J/mol K less than the entropy of the bulk liquid, thus revealing a hindered state of motion of the n-pentane molecules on the surface of rutile. Simulations of the adsorption of n-pentane on the three most abundant crystallographic faces of rutile were also performed. The adsorption isotherm obtained from the combination of each face's isotherm weighted by the respective abundance was found to be in a good agreement with the experimental data. A structural characterization of n-pentane near the surface was also conducted, and it was found that the substrate, especially for the (110) face, strongly perturbs the distribution of n-pentane conformations, compared to those found for the gas phase. Adsorbed molecules are predominantly oriented with their long axes and their backbone zigzag planes parallel to the surface and are also characterized by fewer gauche conformations than observed in the bulk phase.

  17. Effect of separation in n-pentane on storability of sugar maple seeds

    Treesearch

    Clayton M., Jr. Carl

    1976-01-01

    Seeds in samaras separated in n-pentane have been stored successfully for 5½ years. The seeds in the separated samaras germinated equally as well as the unseparated controls, indicating that there was no detrimental effect from the n-pentane.

  18. Hydrogen bond strength and vibrational assignment of the enol form of 3-(ortho-methoxyphenylthio) and 3-(para-methoxyphenylthio)pentane-2,4-dione.

    PubMed

    Zahedi-Tabrizi, Mansoureh; Gerivani, Bentolhoda; Tayyari, Sayyed Faramarz

    2015-02-05

    The molecular structure of 3-(ortho-methoxyphenylthio) pentane-2,4-dione (o-MPTPD) and 3-(para-methoxyphenylthio) pentane-2,4-dione (p-MPTPD) has been investigated by means of Density Functional Theory (DFT) calculations. The results were compared with 3-(phenylthio) pentane-2,4-dione (PTPD), 3-(methylthio) pentane-2,4-dione (MTPD), and their parent, pentane-2,4-dione (known as acetylacetone, AA). The full optimized geometry, the IR and Raman frequencies and their intensities has been calculated at the B3LYP/6-311++G(∗∗) level of theory. The calculated frequencies were compared with the experimental results. The IR and Raman spectra of o-MPTPD and p-MPTPD and their deuterated analogs are recorded in the 3200-200 cm(-1) range. The quantum theory of atoms in molecules (QTAIM) was applied to calculate the topological parameters of electron density distributions and charge transfer energy associated with the intramolecular hydrogen bond (IHB). Natural bond orbital analysis (NBO) was performed for investigation of electron delocalization in these compounds. According to the theoretical and experimental data, the hydrogen bond strength in the 3-thio-pentane-2,4-dione derivatives is much stronger than that in AA. The results of theoretical calculations are in excellent agreement with the vibrational and NMR spectroscopy data. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Extra virgin olive oil aroma release after interaction with human saliva from individuals with different body mass index.

    PubMed

    Genovese, Alessandro; Rispoli, Tiziana; Sacchi, Raffaele

    2018-07-01

    The interindividual variability observed in saliva characteristics raises the question of its relationship with variability in fat sensory perception, particularly in aroma compounds. In the present study, which aimed to measure aroma release from different individuals, eleven key aroma compounds of extra virgin olive oil (EVOO) were monitored and quantified in dynamic headspace after an in vitro interaction between EVOO and human saliva. Therefore, 60 individuals were studied from those who were normal weight (NW), overweight (OW) and obese (O). OW and O demonstrate a higher release of C 6 compounds compared to NW. By contrast, NW have a higher release of C 5 compounds. Pentanal and hexanal also increased after saliva interaction in a refined olive oil that is free from volatiles. Among the saliva samples with a higher release in NW individuals, only pentanal was different. However, the low levels of these lipid oxidation end-products do not appear to be very important with respect to increasing odorous fat sensitivity. The results obtained in the present study demonstrate the important role of saliva in the aroma release of EVOO, indicating that humans can perceive it differently in relation to their body mass index. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  20. Verification of diffusive and pumped samplers for volatile organic compounds using a controlled atmosphere test facility

    NASA Astrophysics Data System (ADS)

    Martin, Nicholas A.; Leming, Edward J.; Henderson, Malcolm H.; Lipscombe, Robert P.; Black, John K.; Jarvis, Scott D.

    2010-09-01

    There is a requirement to verify the performance of sorbent-based passive or active samplers and to extend their use, where possible, to monitor volatile organic compounds (VOCs) that are known to be photochemical ozone pre-cursors or are relevant to the activities of the petrochemical industry. We report measurements of the 14-day diffusive uptake rates for the VOCs: i-butane (2-methyl propane), n-butane, i-pentane (2-methyl butane), n-pentane, n-hexane, benzene, toluene, and m-xylene (at environmental level concentrations) for industry standard axial samplers (Perkin-Elmer-type samplers) containing the sorbents Carbopack-X, -Z, -B or Tenax-TA. We also present data on back-diffusion, blank levels, and storage for the above sorbents, and describe the simultaneous use of the sorbent Carbopack-X for pumped sampling of certain VOCs. The results were obtained by dosing samplers in a controlled atmosphere test facility (CATFAC) operating under well-defined conditions of concentration, nominal temperature of 20 °C, wind speed of 0.5 m s -1, and relative humidities of 0% and 80%. Field measurements were also obtained to provide supplementary data to support the laboratory study. Results are compared to existing published data, where these are available.

  1. Hazardous organic compounds in groundwater near Tehran automobile industry.

    PubMed

    Dobaradaran, Sina; Mahvi, Amir Hossein; Nabizadeh, Ramin; Mesdaghinia, Alireza; Naddafi, Kazem; Yunesian, Masoud; Rastkari, Noushin; Nazmara, Shahrokh

    2010-11-01

    Potential of groundwater contamination by trichloroethylene (TCE) and other volatile organic compounds VOCs near car industry was conducted in this study. TCE, PCE, toluene, xylene, dichloromethane, cyclohexane, n-hexane and n-pentane were detected in all groundwaters. Mean TCE levels in groundwater ranged from 124.37 to 1,035.9 μg L⁻¹ with maximum level of 1,345.7 μg L⁻¹. Due to the data obtained from conventional wastewater treatment in car factory the TCE removal efficiency was only 24 percent which necessitates the TCE removal by advanced treatment processes before the use of well water.

  2. On the behavior of solutions of xenon in liquid n-alkanes: solubility of xenon in n-pentane and n-hexane.

    PubMed

    Bonifácio, Rui P M F; Martins, Luís F G; McCabe, Clare; Filipe, Eduardo J M

    2010-12-09

    The solubility of xenon in liquid n-pentane and n-hexane has been studied experimentally, theoretically, and by computer simulation. Measurements of the solubility are reported for xenon + n-pentane as a function of temperature from 254 to 305 K. The uncertainty in the experimental data is less than 0.15%. The thermodynamic functions of solvation such as the standard Gibbs energy, enthalpy, and entropy of solvation have been calculated from Henry's law coefficients for xenon + n-pentane solutions and also for xenon + n-hexane, which were reported in previous work. The results provide a further example of the similarity between the xenon + n-alkane interaction and the n-alkane + n-alkane interactions. Using the SAFT-VR approach we were able to quantitatively predict the experimental solubility for xenon in n-pentane and semiquantitatively that of xenon in n-hexane using simple Lorentz-Berthelot combining rules to describe the unlikely interaction. Henry's constants at infinite dilution for xenon + n-pentane and xenon + n-hexane were also calculated by Monte Carlo simulation using a united atom force field to describe the n-alkane and the Widom test particle insertion method.

  3. Methyl tert-butyl ether biodegradation by microbial consortia obtained from soil samples of gasoline-polluted sites in Mexico.

    PubMed

    Morales, Marcia; Velázquez, Elia; Jan, Janet; Revah, Sergio; González, Uriel; Razo-Flores, Elías

    2004-02-01

    Microbial consortia obtained from soil samples of gasoline-polluted sites were individually enriched with pentane, hexane, isooctane and toluene. Cometabolism with methyl tert-butyl ether, (MTBE), gave maximum degradation rates of 49, 12, 32 and 0 mg g(-1)protein h(-1), respectively. MTBE was fully degraded even when pentane was completely depleted with a cometabolic coefficient of 1 mgMTBE mg(-1)pentane. The analysis of 16S rDNA from isolated microorganisms in the pentane-adapted consortia showed that microorganisms could be assigned to Pseudomonas. This is the first work reporting the cometabolic mineralization of MTBE by consortium of this genus.

  4. Determination of ethane, pentane and isoprene in exhaled air--effects of breath-holding, flow rate and purified air.

    PubMed

    Lärstad, M A E; Torén, K; Bake, B; Olin, A-C

    2007-01-01

    Exhaled ethane, pentane and isoprene have been proposed as biomarkers of oxidative stress. The objectives were to explore whether ethane, pentane and isoprene are produced within the airways and to explore the effect of different sampling parameters on analyte concentrations. The flow dependency of the analyte concentrations, the concentrations in dead-space and alveolar air after breath-holding and the influence of inhaling purified air on analyte concentrations were investigated. The analytical method involved thermal desorption from sorbent tubes and gas chromatography. The studied group comprised 13 subjects with clinically stable asthma and 14 healthy controls. Ethane concentrations decreased slightly, but significantly, at higher flow rates in subjects with asthma (P = 0.0063) but not in healthy controls. Pentane levels were increased at higher flow rates both in healthy and asthmatic subjects (P = 0.022 and 0.0063 respectively). Isoprene levels were increased at higher flow rates, but only significantly in healthy subjects (P = 0.0034). After breath-holding, no significant changes in ethane levels were observed. Pentane and isoprene levels increased significantly after 20 s of breath-holding. Inhalation of purified air before exhalation resulted in a substantial decrease in ethane levels, a moderate decrease in pentane levels and an increase in isoprene levels. The major fractions of exhaled ethane, pentane and isoprene seem to be of systemic origin. There was, however, a tendency for ethane to be flow rate dependent in asthmatic subjects, although to a very limited extent, suggesting that small amounts of ethane may be formed in the airways.

  5. Coupled-cluster, Möller Plesset (MP2), Density Fitted Local MP2, and Density Functional Theory Examination of the Energetic and Structural Features of Hydrophobic Solvation: Water and Pentane

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ghadar, Yasaman; Clark, Aurora E.

    2012-02-02

    The interaction potentials between immiscible polar and non-polar solvents are a major driving force behind the formation of liquid:liquid interfaces. In this work, the interaction energy of water–pentane dimer has been determined using coupled-cluster theory with single double (triple) excitations [CCSD(T)], 2nd order Möller Plesset perturbation theory (MP2), density fitted local MP2 (DF-LMP2), as well as density functional theory using a wide variety of density functionals and several different basis sets. The M05-2X exchange correlation functionals exhibit excellent agreement with CCSD(T) and DF-LMP2 after taking into account basis set superposition error. The gas phase water–pentane interaction energy is found tomore » be quite sensitive to the specific pentane isomer (2,2- dimethylpropane vs. n-pentane) and relative orientation of the monomeric constituents. Subsequent solution phase cluster calculations of 2,2-dimethylpropane and n-pentane solvated by water indicate a positive free energy of solvation that is in good agreement with available experimental data. Structural parameters are quite sensitive to the density functional employed and reflect differences in the two-body interaction energy calculated by each method. In contrast, cluster calculations of pentane solvation of H2O solute are found to be inadequate for describing the organic solvent, likely due to limitations associated with the functionals employed (B3LYP, BHandH, and M05-2X).« less

  6. Gravity Effects in Condensing and Evaporating Films

    NASA Technical Reports Server (NTRS)

    Hermanson, J. C.; Som, S. M.; Allen, J. S.; Pedersen, P. C.

    2004-01-01

    A general overview of gravity effects in condensing and evaporating films is presented. The topics include: 1) Research Overview; 2) NASA Recognizes Critical Need for Condensation & Evaporation Research to Enable Human Exploration of Space; 3) Condensation and Evaporation Research in Reduced Gravity is Enabling for AHST Technology Needs; 4) Differing Role of Surface Tension on Condensing/Evaporating Film Stability; 5) Fluid Mechanisms in Condensing and Evaporating Films in Reduced Gravity; 6) Research Plan; 7) Experimental Configurations for Condensing Films; 8) Laboratory Condensation Test Cell; 9) Aircraft Experiment; 10) Condensation Study Current Test Conditions; 11) Diagnostics; 12) Shadowgraph Images of Condensing n- pentane Film in Unstable (-1g) Configuration; 13) Condensing n-Pentane Film in Normal Gravity (-1g) at Constant Pressure; 14) Condensing n-Pentane Film in Normal Gravity (-1g) with Cyclic Pressure; 15) Non-condensing Pumped Film in Normal Gravity (-1g); 16) Heat Transfer Coefficient in Developing, Unstable Condensing Film in Normal Gravity; 17) Heat Transfer for Unsteady Condensing Film (-1g); 18) Ultrasound Measurement of Film Thickness N-pentane Film, Stable (+1g) Configuration; and 19) Ultrasound Measurement of Film Thickness N-pentane Film, Unstable (-1g) Configuration.

  7. Refining of Military Jet Fuels from Shale Oil. Part III. Pilot Plant Sample Preparation.

    DTIC Science & Technology

    1982-07-01

    product gas composition, regen- erator flue gas composition, and carbon contents of the spent and regenerated catalysts were also monitored for...product. Gas samples were collected at eight-hour intervals from the reactor product gas and regenerator flue gas streams and analyzed for material balance...Isobutane C4= Butylene C5 Pentane C5s Pentane and Pentenes I+ C5+, >C5 Compounds Heavier than Pentane in Gas .* Streams C6 Hexane C/H Carbon-to

  8. 26 CFR 48.4081-1 - Taxable fuel; definitions.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... xylene); (L) Natural gasoline; (M) Pentane; (N) Pentane mixture; (O) Polymer gasoline; (P) Raffinate; (Q... hydrocarbon stream that is produced in a natural gas processing plant is not a gasoline blendstock if the...

  9. The equation of state of n-pentane in the atomistic model TraPPE-EH

    NASA Astrophysics Data System (ADS)

    Valeev, B. U.; Pisarev, V. V.

    2018-01-01

    In this work, we study the vapor-liquid equilibrium in n-pentane. We use the TraPPE-EH (transferable potentials for phase equilibria-explicit hydrogen) forcefield, where each hydrogen and carbon atom is considered as independent center of force. The fluid behavior was investigated with different values of density and temperature by molecular dynamics method. The n-pentane evaporation curve was calculated in the temperature range of 290 to 390 K. The densities of the coexisting phases are also calculated. The compression curve at 370 K was calculated and isothermal bulk modulus was found. The simulated properties of n-pentane are in good agreement with data from a database of the National Institute of Standards and Technology, so the TraPPE-EH model can be recommended for simulations of hydrocarbons.

  10. Effect of Fuel Composition on Particulate Matter Emissions from a Gasoline Direct Injection Engine

    NASA Astrophysics Data System (ADS)

    Smallwood, Bryden Alexander

    The effects of fuel composition on reducing PM emissions were investigated using a Ford Focus wall-guided gasoline direct injection engine (GDI). Initial results with a 65% isooctane and 35% toluene blend showed significant reductions in PM emissions. Further experiments determined that this decrease was due to a lack of light-end components in that fuel blend. Tests with pentane content lower than 15% were found to have PN concentrations 96% lower than tests with 20% pentane content. This indicates that there is a shift in mode of soot production. Pentane significantly increases the vapour pressure of the fuel blend, potentially resulting in surface boiling, less homogeneous mixtures, or decreased fuel rebound from the piston. PM mass measurements and PN Index values both showed strong correlations with the PN concentration emissions. In the gaseous exhaust, THC, pentane, and 1,3 butadiene showed strong correlations with the PM emissions.

  11. Intermolecular network analysis of the liquid and vapor interfaces of pentane and water: microsolvation does not trend with interfacial properties.

    PubMed

    Ghadar, Yasaman; Clark, Aurora E

    2014-06-28

    Liquid:vapor and liquid:liquid interfaces exhibit complex organizational structure and dynamics at the molecular level. In the case of water and organic solvents, the hydrophobicity of the organic, its conformational flexibility, and compressibility, all influence interfacial properties. This work compares the interfacial tension, width, molecular conformations and orientations at the vapor and aqueous liquid interfaces of two solvents, n-pentane and neopentane, whose varying molecular shapes can lead to significantly different interfacial behavior. Particular emphasis has been dedicated toward understanding how the hydrogen bond network of water responds to the pentane relative to the vapor interface and the sensitivity of the network to the individual pentane isomer and system temperature. Interfacial microsolvation of the immiscible solvents has been examined using graph theoretical methods that quantify the structure and dynamics of microsolvated species (both H2O in C5H12 and C5H12 in H2O). At room temperature, interfacial water at the pentane phase boundary is found to have markedly different organization and dynamics than at the vapor interface (as indicated by the hydrogen bond distributions and hydrogen bond persistence in solution). While the mesoscale interfacial properties (e.g. interfacial tension) are sensitive to the specific pentane isomer, the distribution and persistence of microsolvated species at the interface is nearly identical for both systems, irrespective of temperature (between 273 K and 298 K). This has important implications for understanding how properties defined by the interfacial organization are related to the underlying solvation reactions that drive formation of the phase boundary.

  12. Catalytic coal liquefaction with treated solvent and SRC recycle

    DOEpatents

    Garg, Diwakar; Givens, Edwin N.; Schweighardt, Frank K.

    1986-01-01

    A process for the solvent refining of coal to distillable, pentane soluble products using a dephenolated and denitrogenated recycle solvent and a recycled, pentane-insoluble, solvent-refined coal material, which process provides enhanced oil-make in the conversion of coal.

  13. Catalytic coal liquefaction with treated solvent and SRC recycle

    DOEpatents

    Garg, D.; Givens, E.N.; Schweighardt, F.K.

    1986-12-09

    A process is described for the solvent refining of coal to distillable, pentane soluble products using a dephenolated and denitrogenated recycle solvent and a recycled, pentane-insoluble, solvent-refined coal material, which process provides enhanced oil-make in the conversion of coal. 2 figs.

  14. A New Exploration of the Torsional Energy Surface of N-Pentane Using Molecular Modeling Software

    ERIC Educational Resources Information Center

    Galembeck, Sergio E.; Caramori, Giovanni F.; Romero, Jose Ricardo

    2005-01-01

    The torsional potential energy surface of a chemical compounds, the accessible conformations at a specified temperature and the transition states that connect these confirmations establishes many chemical properties such as dynamic behavior, reactivity and biological activity. A conformational search of n-pentane is presented using computational…

  15. Central Appalachian basin natural gas database: distribution, composition, and origin of natural gases

    USGS Publications Warehouse

    Román Colón, Yomayra A.; Ruppert, Leslie F.

    2015-01-01

    The U.S. Geological Survey (USGS) has compiled a database consisting of three worksheets of central Appalachian basin natural gas analyses and isotopic compositions from published and unpublished sources of 1,282 gas samples from Kentucky, Maryland, New York, Ohio, Pennsylvania, Tennessee, Virginia, and West Virginia. The database includes field and reservoir names, well and State identification number, selected geologic reservoir properties, and the composition of natural gases (methane; ethane; propane; butane, iso-butane [i-butane]; normal butane [n-butane]; iso-pentane [i-pentane]; normal pentane [n-pentane]; cyclohexane, and hexanes). In the first worksheet, location and American Petroleum Institute (API) numbers from public or published sources are provided for 1,231 of the 1,282 gas samples. A second worksheet of 186 gas samples was compiled from published sources and augmented with public location information and contains carbon, hydrogen, and nitrogen isotopic measurements of natural gas. The third worksheet is a key for all abbreviations in the database. The database can be used to better constrain the stratigraphic distribution, composition, and origin of natural gas in the central Appalachian basin.

  16. Strain Release Amination

    PubMed Central

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

    2015-01-01

    To optimize drug candidates, modern medicinal chemists are increasingly turning to an unconventional structural motif: small, strained ring systems. However, the difficulty of introducing substituents such as bicyclo[1.1.1]pentanes, azetidines, or cyclobutanes often outweighs the challenge of synthesizing the parent scaffold itself. Thus, there is an urgent need for general methods to rapidly and directly append such groups onto core scaffolds. Here we report a general strategy to harness the embedded potential energy of effectively spring-loaded C–C and C–N bonds with the most oft-encountered nucleophiles in pharmaceutical chemistry, amines. Strain release amination can diversify a range of substrates with a multitude of desirable bioisosteres at both the early and late-stages of a synthesis. The technique has also been applied to peptide labeling and bioconjugation. PMID:26816372

  17. Binary chromatographic data and estimation of adsorbent porosities. [data for system n-heptane/n-pentane

    NASA Technical Reports Server (NTRS)

    Meisch, A. J.

    1972-01-01

    Data for the system n-pentane/n-heptane on porous Chromosorb-102 adsorbent were obtained at 150, 175, and 200 C for mixtures containing zero to 100% n-pentane by weight. Prior results showing limitations on superposition of pure component data to predict multicomponent chromatograms were verified. The thermodynamic parameter MR0 was found to be a linear function of sample composition. A nonporous adsorbent failed to separate the system because of large input sample dispersions. A proposed automated data processing scheme involving magnetic tape recording of the detector signals and processing by a minicomputer was rejected because of resolution limitations of the available a/d converters. Preliminary data on porosity and pore size distributions of the adsorbents were obtained.

  18. Electron Transport in Paracoccus Halodenitrificans and the Role of Ubiquinone

    NASA Technical Reports Server (NTRS)

    Hochstein, L. I.; Cronin, S. E.

    1983-01-01

    The membrane-bound NADH oxidase of Paracoccus halodenitrificans was inhibited by dicoumarol, 2-n-heptyl-4-hydroxyquinoline-N-oxide (HQNO), and exposure to ultraviolet light (at 366 nm). When the membranes were extracted with n-pentane, NADH oxidase activity was lost. Partial restoration was achieved by adding the ubiquinone fraction extracted from the membranes. Succinate oxidation was not inhibited by dicoumarol or HQNO but was affected by ultraviolet irradiation or n-pentane extraction. However, the addition of the ubiquinone fraction to the n-pentane-extracted membranes did not restore enzyme activity. These observations suggested the reducing equivalents from succinate entered the respiratory chain on the oxygen side of the HQNO-sensitive site and probably did not proceed through a quinone.

  19. Electron transport in Paracoccus halodenitrificans and the role of Ubiquinone

    NASA Technical Reports Server (NTRS)

    Hochstein, L. I.; Cronin, S. E.

    1984-01-01

    The membrane-bound NADH oxidase of Paracoccus halodenitrificans was inhibited by dicoumarol, 2-n-heptyl-4-hydroxyquinoline-N-oxide (HQNO), and exposure to ultraviolet light (at 366 nm). When the membranes were extracted with n-pentane, NADH oxidase activity was lost. Partial restoration was achieved by adding the ubiquinone fraction extracted from the membranes. Succinate oxidation was not inhibited by dicoumarol or HQNO but was affected by ultraviolet irradiation or n-pentane extraction. However, the addition of the ubiquinone fraction to the n-pentane-extracted membranes did not restore enzyme activity. These observations suggested the reducing equivalents from succinate entered the respiratory chain on the oxygen side of the HQNO-sensitive site and probably did not proceed through a quinone.

  20. 77 FR 9947 - Guidance for Industry: Early Clinical Trials With Live Biotherapeutic Products: Chemistry...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-21

    ...] Guidance for Industry: Early Clinical Trials With Live Biotherapeutic Products: Chemistry, Manufacturing... ``Guidance for Industry: Early Clinical Trials With Live Biotherapeutic Products: Chemistry, Manufacturing... for Industry: Early Clinical Trials With Live Biotherapeutic Products: Chemistry, Manufacturing, and...

  1. Production of Reactive Oxygen Species by Polyhalogenated Cyclic Hydrocarbons (PCH)

    DTIC Science & Technology

    1991-07-22

    dry ice in metabolism cages. One ml aliquots of urine were derivatized with 2,4- dinitrophenylhydrazine , and extracted with pentane. The hydrazones of...U.S.A. Key Words: formaldehyde; acetaldehyde; malondialdehyde; acetone; high pressure liquid chromatography; 2,4- dinitrophenylhydrazine ; gas... dinitrophenylhydrazine , and extracted with pentane. The hydrazones of the four lipid metabolic products were quantitated by high pressure liquid chromatography

  2. Influences of the molecular fuel structure on combustion reactions towards soot precursors in selected alkane and alkene flames.

    PubMed

    Ruwe, Lena; Moshammer, Kai; Hansen, Nils; Kohse-Höinghaus, Katharina

    2018-04-25

    In this study, we experimentally investigate the high-temperature oxidation kinetics of n-pentane, 1-pentene and 2-methyl-2-butene (2M2B) in a combustion environment using flame-sampling molecular beam mass spectrometry. The selected C5 fuels are prototypes for linear and branched, saturated and unsaturated fuel components, featuring different C-C and C-H bond structures. It is shown that the formation tendency of species, such as polycyclic aromatic hydrocarbons (PAHs), yielded through mass growth reactions increases drastically in the sequence n-pentane < 1-pentene < 2M2B. This comparative study enables valuable insights into fuel-dependent reaction sequences of the gas-phase combustion mechanism that provide explanations for the observed difference in the PAH formation tendency. First, we investigate the fuel-structure-dependent formation of small hydrocarbon species that are yielded as intermediate species during the fuel decomposition, because these species are at the origin of the subsequent mass growth reaction pathways. Second, we review typical PAH formation reactions inspecting repetitive growth sequences in dependence of the molecular fuel structure. Third, we discuss how differences in the intermediate species pool influence the formation reactions of key aromatic ring species that are important for the PAH growth process underlying soot formation. As a main result it was found that for the fuels featuring a C[double bond, length as m-dash]C double bond, the chemistry of their allylic fuel radicals and their decomposition products strongly influences the combination reactions to the initially formed aromatic ring species and as a consequence, the PAH formation tendency.

  3. Industrial Chemistry: A Series of New Courses at the Undergraduate Level.

    ERIC Educational Resources Information Center

    Jasinski, Jerry P.; Miller, Robert E.

    1985-01-01

    Describes four courses in the undergraduate bachelor of science program in industrial chemistry at Keene State College (NH). They are (1) introduction to industrial chemistry; (2) polymers--synthesis and separation techniques; (3) inorganic industrial processes; and (4) organic industrial processes. (JN)

  4. Cascade upgrading of γ-valerolactone to biofuels.

    PubMed

    Yan, Kai; Lafleur, Todd; Wu, Xu; Chai, Jiajue; Wu, Guosheng; Xie, Xianmei

    2015-04-25

    Cascade upgrading of γ-valerolactone (GVL), produced from renewable cellulosic biomass, with selective conversion to biofuels pentyl valerate (PV) and pentane in one pot using a bifunctional Pd/HY catalyst is described. Excellent catalytic performance (over 99% conversion of GVL, 60.6% yield of PV and 22.9% yield of pentane) was achieved in one step. These biofuels can be targeted for gasoline and jet fuel applications.

  5. On Study of New Progress and Application of Coordination Chemistry in Chemistry and Chemical Industry in Recent Years

    NASA Astrophysics Data System (ADS)

    Zhang, Yunshen

    2017-12-01

    Coordination chemistry refers to a branch of chemistry, and its research results are widely used in industry and people's daily life. Many edge disciplines emerge during the development, which propels the process of disciplines and technology. This paper briefly discusses new progress of coordination chemistry and its application in chemistry and chemical industry in recent years.

  6. Stimulated raman scattering of fuel droplets

    NASA Astrophysics Data System (ADS)

    Acker, William P.; Serpengüzel, Ali; Chang, Richard K.; Hill, Steven C.

    1990-07-01

    The strong stimulated Raman scattering (SRS) from diesel fuel droplets has the potential of providing the relative concentration of multicomponent fuel and the absolute size of individual droplets. The morphology-dependent resonances (MDRs) of a sphere cause the droplet to act as an optical resonator which greatly lowers the SRS threshold. The number density, quality factor, and frequency shift of several MDRs are calculated as a function of the ratio of the index of refraction of the liquid and the surrounding gas, which approaches unity at the thermodynamic critical condition for the fuel spray. The SRS spectra of monodispersed droplets of toluene, pentane, Exxon-Aromatic-150, and Mobil D-2 are presented. The exponential growth region of the SRS intensity I 1S as a function of the input laser intensity I input is investigated for the toluene carbon ring breathing mode v 2 and the pentane C-H stretching region. The I 1S ratio of toluene and pentane is measured as a function of the ratio of the toluene and pentane concentration for monodispersed droplets. The reduced fluctuation in I 1S when I input is changed from multimode to single-mode is displayed as a histogram of the I 1S of the v 2 mode of toluene droplets.

  7. Headspace Solid-Phase Microextraction and Ultrasonic Extraction with the Solvent Sequences in Chemical Profiling of Allium ursinum L. Honey.

    PubMed

    Jerković, Igor; Kuś, Piotr M

    2017-11-06

    A volatile profile of ramson (wild garlic, Allium ursinum L.) honey was investigated by headspace solid-phase microextraction (HS-SPME) and ultrasonic solvent extraction (USE) followed by gas chromatography and mass spectrometry (GC-FID/GC-MS) analyses. The headspace was dominated by linalool derivatives: cis - and trans -linalool oxides (25.3%; 9.2%), hotrienol (12.7%), and linalool (5.8%). Besides direct extraction with dichloromethane and pentane/diethyl ether mixture (1:2, v / v ), two solvent sequences (I: pentane → diethyl ether; II: pentane → pentane/diethyl ether (1:2, v / v ) → dichloromethane) were applied. Striking differences were noted among the obtained chemical profiles. The extracts with diethyl ether contained hydroquinone (25.8-36.8%) and 4-hydroxybenzoic acid (11.6-16.6%) as the major compounds, while ( E )-4-(r-1',t-2',c-4'-trihydroxy-2',6',6'-trimethylcyclohexyl)but-3-en-2-one predominated in dichloromethane extracts (18.3-49.1%). Therefore, combination of different solvents was crucial for the comprehensive investigation of volatile organic compounds in this honey type. This particular magastigmane was previously reported only in thymus honey and hydroquinone in vipers bugloss honey, while a combination of the mentioned predominant compounds is unique for A. ursinum honey.

  8. Vapor phase nucleation of the short-chain n-alkanes (n-pentane, n-hexane and n-heptane): Experiments and Monte Carlo simulations.

    PubMed

    Ogunronbi, Kehinde E; Sepehri, Aliasghar; Chen, Bin; Wyslouzil, Barbara E

    2018-04-14

    We measured the nucleation rates of n-pentane through n-heptane in a supersonic nozzle at temperatures ranging from ca. 109 K to 168 K. For n-pentane and n-hexane, these are the first nucleation rate measurements that have been made, and the trends in the current data agree well with those in the earlier work of Ghosh et al. [J. Chem. Phys. 132, 024307 (2010)] for longer chain alkanes. Complementary Monte Carlo simulations, using the transferable potentials for phase equilibria-united atom potentials, suggest that despite the high degree of supercooling, the critical clusters remain liquid like under experimental conditions for n-pentane through n-heptane, but adopt more ordered structures for n-octane and n-nonane. For all three alkanes, the experimental and simulated nucleation rates are offset by ∼3 orders of magnitude when plotted as a function of ln S/(T c /T - 1) 1.5 . Explicitly accounting for the surface tension difference between the real and model substances, or alternatively using the Hale [Phys. Rev. A 33, 4156 (1986); Metall. Mater. Trans. A 23, 1863 (1992)] scaling parameter, Ω, consistent with the model potential, increases the offset to ∼6 orders of magnitude.

  9. Vapor phase nucleation of the short-chain n-alkanes (n-pentane, n-hexane and n-heptane): Experiments and Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Ogunronbi, Kehinde E.; Sepehri, Aliasghar; Chen, Bin; Wyslouzil, Barbara E.

    2018-04-01

    We measured the nucleation rates of n-pentane through n-heptane in a supersonic nozzle at temperatures ranging from ca. 109 K to 168 K. For n-pentane and n-hexane, these are the first nucleation rate measurements that have been made, and the trends in the current data agree well with those in the earlier work of Ghosh et al. [J. Chem. Phys. 132, 024307 (2010)] for longer chain alkanes. Complementary Monte Carlo simulations, using the transferable potentials for phase equilibria-united atom potentials, suggest that despite the high degree of supercooling, the critical clusters remain liquid like under experimental conditions for n-pentane through n-heptane, but adopt more ordered structures for n-octane and n-nonane. For all three alkanes, the experimental and simulated nucleation rates are offset by ˜3 orders of magnitude when plotted as a function of ln S/(Tc/T - 1)1.5. Explicitly accounting for the surface tension difference between the real and model substances, or alternatively using the Hale [Phys. Rev. A 33, 4156 (1986); Metall. Mater. Trans. A 23, 1863 (1992)] scaling parameter, Ω, consistent with the model potential, increases the offset to ˜6 orders of magnitude.

  10. Thermodynamic properties of isomeric pentanols under elevated pressures determined by the acoustic method

    NASA Astrophysics Data System (ADS)

    Dzida, M.

    2008-02-01

    Three isomeric pentanols were studied: pentan-1-ol, 2-methyl-1-buta- nol, and 2-methyl-2-butanol. Isobaric heat capacities and internal pressure at pressures up to 100 MPa and temperatures ranging from 293 K to 318 K were determined by the acoustic method. In calculations the measured speeds of sound as function of temperature and pressure together with densities as function of temperature under atmospheric pressure and the literature isobaric heat capacities for the atmospheric pressure were used. To this end, the method, based on the suggestion of Davis and Gordon [1] was applied. The results obtained show that the effect of pressure on and the values of isobaric heat capacity and internal presure of 2-methyl-2-butanol is higher than that of pentan-1-ol, 2-methyl-1-butanol over the whole pressure range. That facilitates telling 2-methyl-2-butanol from pentan-1-ol and 2-methyl-1-butanol.

  11. Conservative and dissipative force field for simulation of coarse-grained alkane molecules: A bottom-up approach

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Trément, Sébastien; Rousseau, Bernard, E-mail: bernard.rousseau@u-psud.fr; Schnell, Benoît

    2014-04-07

    We apply operational procedures available in the literature to the construction of coarse-grained conservative and friction forces for use in dissipative particle dynamics (DPD) simulations. The full procedure rely on a bottom-up approach: large molecular dynamics trajectories of n-pentane and n-decane modeled with an anisotropic united atom model serve as input for the force field generation. As a consequence, the coarse-grained model is expected to reproduce at least semi-quantitatively structural and dynamical properties of the underlying atomistic model. Two different coarse-graining levels are studied, corresponding to five and ten carbon atoms per DPD bead. The influence of the coarse-graining levelmore » on the generated force fields contributions, namely, the conservative and the friction part, is discussed. It is shown that the coarse-grained model of n-pentane correctly reproduces self-diffusion and viscosity coefficients of real n-pentane, while the fully coarse-grained model for n-decane at ambient temperature over-predicts diffusion by a factor of 2. However, when the n-pentane coarse-grained model is used as a building block for larger molecule (e.g., n-decane as a two blobs model), a much better agreement with experimental data is obtained, suggesting that the force field constructed is transferable to large macro-molecular systems.« less

  12. Groundwater chemistry in the vicinity of the Puna Geothermal Venture Power Plant, Hawai‘i, after two decades of production

    USGS Publications Warehouse

    Evans, W.C.; Bergfeld, D.; Sutton, A.J.; Lee, R.C.; Lorenson, T.D.

    2015-01-01

    We report chemical data for selected shallow wells and coastal springs that were sampled in 2014 to determine whether geothermal power production in the Puna area over the past two decades has affected the characteristics of regional groundwater. The samples were analyzed for major and minor chemical species, trace metals of environmental concern, stable isotopes of water, and two organic compounds (pentane and isopropanol) that are injected into the deep geothermal reservoir at the power plant. Isopropanol was not detected in any of the groundwaters; confirmed detection of pentane was restricted to one monitoring well near the power plant at a low concentration not indicative of source. Thus, neither organic compound linked geothermal operations to groundwater contamination, though chemical stability and transport velocity questions exist for both tracers. Based on our chemical analysis of geothermal fluid at the power plant and on many similar results from commercially analyzed samples, we could not show that geothermal constituents in the groundwaters we sampled came from the commercially developed reservoir. Our data are consistent with a long-held view that heat moves by conduction from the geothermal reservoir into shallow groundwaters through a zone of low permeability rock that blocks passage of geothermal water. The data do not rule out all impacts of geothermal production on groundwater. Removal of heat during production, for example, may be responsible for minor changes that have occurred in some groundwater over time, such as the decline in temperature of one monitoring well near the power plant. Such indirect impacts are much harder to assess, but point out the need for an ongoing groundwater monitoring program that should include the coastal springs down-gradient from the power plant.

  13. Redox Chemistry of Gold(I) Phosphine Thiolates: Sulfur-Based Oxidation

    PubMed Central

    Jiang, Tong; Wei, Gang; Turmel, Cristopher; Bruce, Alice E.

    1994-01-01

    The redox chemistry of mononuclear and dinuclear gold(I) phosphine arylthiolate complexes was recently investigated by using electrochemical, chemical, and photochemical techniques. We now report the redox chemistry of dinuclear gold(I) phosphine complexes containing aliphatic dithiolate ligands. These molecules differ from previously studied gold(I) phosphine thiolate complexes in that they are cyclic and contain aliphatic thiolates. Cyclic voltammetry experiments of Au2 (LL)(pdt) [pdt = propanedithiol; LL = 1,2-bis(diphenylphosphino)-ethane (dppe), 1,3-bis(diphenylphosphino)propane (dppp), 1,4-bis(diphenylphosphino)butane (dppb), 1,5-bis(diphenylphosphino)pentane (dpppn)] in 0.1 M TBAH/CH3CN or CH2Cl2 solutions at 50 to 500 mV/sec using glassy carbon or platinum electrodes, show two irreversible anodic processes at ca. +0.6 and +1.1 V (vs. SCE). Bulk electrolyses at +0.9 V and +1.4 V result in n values of 0.95 and 3.7, respectively. Chemical oxidation of Au2(dppp)(pdt) using one equivalent of Br2 (2 oxidizing equivalents) yields 1,2-dithiolane and Au2(dppp)Br2. The reactivity seen upon mild oxidation ≤ +1.0 V is consistent with formal oxidation of a thiolate ligand, followed by a fast chemical reaction that results in cleavage of a second gold-sulfur bond. Oxidation at higher potentials (≥ +1.3 V) is consistent with oxidation of gold(I) to gold(III). Structural and electrochemical differences between gold(I) aromatic and aliphatic thiolate oxidation processes are discussed. PMID:18476260

  14. The future of discovery chemistry: quo vadis? Academic to industrial--the maturation of medicinal chemistry to chemical biology.

    PubMed

    Hoffmann, Torsten; Bishop, Cheryl

    2010-04-01

    At Roche, we set out to think about the future role of medicinal chemistry in drug discovery in a project involving both Roche internal stakeholders and external experts in drug discovery chemistry. To derive a coherent strategy, selected scientists were asked to take extreme positions and to derive two orthogonal strategic options: chemistry as the traditional mainstream science and chemistry as the central entrepreneurial science. We believe today's role of medicinal chemistry in industry has remained too narrow. To provide the innovation that industry requires, medicinal chemistry must play its part and diversify at pace with our increasing understanding of chemical biology and network pharmacology. 2010 Elsevier Ltd. All rights reserved.

  15. Liquid CO2 extraction of Jasminum grandiflorum and comparison with conventional processes.

    PubMed

    Prakash, Om; Sahoo, Deeptanjali; Rout, Prasant Kumar

    2012-01-01

    The concrete (0.35%) of Jasminum grandiflorum L. flowers was prepared by extraction in n-pentane, and the absolute (0.27%) by fractionation of the n-pentane extract (concrete) with cold methanol. Direct extraction of flowers with liquid CO2 gave a relatively fat-free product in 0.26% yield. The liquid CO2 extract was enriched with terpenoids and benzenoids, thus providing the organoleptically accepted product. The major compounds, such as benzyl acetate, (E,E)-alpha-farnesene and (Z)-3-hexenyl benzoate, along with compounds like indole, methyl anthranilate, (Z)-jasmone, (Z)-methyl jasmonoate and (Z)-methyl epi-jasmonoate, are responsible for the high diffusivity of the jasmine fragrance. These compounds have been obtained with improved recoveries in the liquid CO2 extract. On the other hand, the yield of the essential oil was poor (0.05%), and some polar compounds (oxygenated terpenoids) were recovered in less amounts in comparison with either the n-pentane or liquid CO2 extract.

  16. Swelling behaviour in n-pentane and mechanical properties of epoxidized natural rubber with different epoxide content

    NASA Astrophysics Data System (ADS)

    Kinasih, N. A.; Fathurrohman, M. I.; Winarto, D. A.

    2017-07-01

    Epoxidized natural rubber (ENR) with different level of epoxidation (i.e. 10, 20, 30, 40 and 50 mol% indicated as ENR ENR10, ENR20, ENR30, ENR40 and ENR50, respectively) were prepared. They were then vulcanized by using efficient system vulcanization. The effect of epoxide content on curing characteristic, swelling and mechanical properties in N-pentane was investigated. The Attenuated Resonance Fourier Transform Infrared (ATR-FTIR) and H-Nuclear Magnetic Resonance (H-NMR) were used to determine the epoxidation level. Glass transition (Tg) of ENR samples was determined by using Direct Scanning Calorimetry (DSC). The result revealed that the resistance of ENR in N-pentane increased with increasing epoxidation level, which indicated by decreasing equilibrium mol uptake and diffusion coefficient. The compression set of ENR and aging resistance increased with increasing epoxide content, except ENR50 was due to ENR 50 have two Tg value. However, the value of hardness and tensile strength were not effected by epoxidation level.

  17. The simulation of organic rankine cycle power plant with n-pentane working fluid

    NASA Astrophysics Data System (ADS)

    Nurhilal, Otong; Mulyana, Cukup; Suhendi, Nendi; Sapdiana, Didi

    2016-02-01

    In the steam power plant in Indonesia the dry steam from separator directly used to drive the turbin. Meanwhile, brine from the separator with low grade temperature reinjected to the earth. The brine with low grade temperature can be converted indirectly to electrical power by organic Rankine cycle (ORC) methods. In ORC power plant the steam are released from vaporization of organic working fluid by brine. The steam released are used to drive an turbine which in connected to generator to convert the mechanical energy into electric energy. The objective of this research is the simulation ORC power plant with n-pentane as organic working fluid. The result of the simulation for brine temperature around 165°C and the pressure 8.001 bar optained the net electric power around 1173 kW with the cycle thermal efficiency 14.61% and the flow rate of n-pentane around 15.51 kg/s. This result enable to applied in any geothermal source in Indonesia.

  18. 75 FR 63188 - Draft Guidance for Industry: Early Clinical Trials With Live Biotherapeutic Products: Chemistry...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-14

    ...] Draft Guidance for Industry: Early Clinical Trials With Live Biotherapeutic Products: Chemistry...: Chemistry, Manufacturing, and Control Information'' dated September 2010. The draft guidance provides... Products: Chemistry, Manufacturing, and Control Information'' dated September 2010. The draft guidance...

  19. Experimental study of the heated contact line region for a pure fluid and binary fluid mixture in microgravity.

    PubMed

    Nguyen, Thao T T; Kundan, Akshay; Wayner, Peter C; Plawsky, Joel L; Chao, David F; Sicker, Ronald J

    2017-02-15

    Understanding the dynamics of phase change heat and mass transfer in the three-phase contact line region is a critical step toward improving the efficiency of phase change processes. Phase change becomes especially complicated when a fluid mixture is used. In this paper, a wickless heat pipe was operated on the International Space Station (ISS) to study the contact line dynamics of a pentane/isohexane mixture. Different interfacial regions were identified, compared, and studied. Using high resolution (50×), interference images, we calculated the curvature gradient of the liquid-vapor interface at the contact line region along the edges of the heat pipe. We found that the curvature gradient in the evaporation region increases with increasing heat flux magnitude and decreasing pentane concentration. The curvature gradient for the mixture case is larger than for the pure pentane case. The difference between the two cases increases as pentane concentration decreases. Our data showed that the curvature gradient profile within the evaporation section is separated into two regions with the boundary between the two corresponding to the location of a thick, liquid, "central drop" region at the point of maximum internal local heat flux. We found that the curvature gradients at the central drop and on the flat surfaces where condensation begins are one order of magnitude smaller than the gradients in the corner meniscus indicating the driving forces for fluid flow are much larger in the corners. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Preferential methanogenic biodegradation of short-chain n-alkanes by microbial communities from two different oil sands tailings ponds.

    PubMed

    Mohamad Shahimin, Mohd Faidz; Foght, Julia M; Siddique, Tariq

    2016-05-15

    Oil sands tailings ponds harbor diverse anaerobic microbial communities capable of methanogenic biodegradation of solvent hydrocarbons entrained in the tailings. Mature fine tailings (MFT) from two operators (Albian and CNRL) that use different extraction solvents were incubated with mixtures of either two (n-pentane and n-hexane) or four (n-pentane, n-hexane, n-octane and n-decane) n-alkanes under methanogenic conditions for ~600 d. Microbes in Albian MFT began methane production by ~80 d, achieving complete depletion of n-pentane and n-hexane in the two-alkane mixture and their preferential biodegradation in the four-alkane mixture. Microbes in CNRL MFT preferentially metabolized n-octane and n-decane in the four-alkane mixture after a ~80 d lag but exhibited a lag of ~360 d before commencing biodegradation of n-pentane and n-hexane in the two-alkane mixture. 16S rRNA gene pyrosequencing revealed Peptococcaceae members as key bacterial n-alkane degraders in all treatments except CNRL MFT amended with the four-alkane mixture, in which Anaerolineaceae, Desulfobacteraceae (Desulfobacterium) and Syntrophaceae (Smithella) dominated during n-octane and n-decane biodegradation. Anaerolineaceae sequences increased only in cultures amended with the four-alkane mixture and only during n-octane and n-decane biodegradation. The dominant methanogens were acetoclastic Methanosaetaceae. These results highlight preferential n-alkane biodegradation by microbes in oil sands tailings from different producers, with implications for tailings management and reclamation. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Sorption and phase distribution of ethanol and butanol blended gasoline vapours in the vadose zone after release.

    PubMed

    Ugwoha, Ejikeme; Andresen, John M

    2014-03-01

    The sorption and phase distribution of 20% ethanol and butanol blended gasoline (E20 and B20) vapours have been examined in soils with varying soil organic matter (SOM) and water contents via laboratory microcosm experiments. The presence of 20% alcohol reduced the sorption of gasoline compounds by soil as well as the mass distribution of the compounds to soil solids. This effect was greater for ethanol than butanol. Compared with the sorption coefficient (Kd) of unblended gasoline compounds, the Kd of E20 gasoline compounds decreased by 54% for pentane, 54% for methylcyclopentane (MCP) and 63% for benzene, while the Kd of B20 gasoline compounds decreased by 39% for pentane, 38% for MCP and 49% for benzene. The retardation factor (R) of E20 gasoline compounds decreased by 53% for pentane, 53% for MCP and 48% for benzene, while the R of B20 gasoline compounds decreased by 39% for pentane, 37% for MCP and 38% for benzene. For all SOM and water contents tested, the Kd and R of all gasoline compounds were in the order of unblended gasoline > B20 > E20, indicating that the use of high ethanol volume in gasoline to combat climate change could put the groundwater at greater risk of contamination. Copyright © 2014 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  2. 75 FR 47604 - Guidance for Industry on Drug Substance Chemistry, Manufacturing, and Controls Information...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-06

    ...] (formerly 2003D-0571) Guidance for Industry on Drug Substance Chemistry, Manufacturing, and Controls... Substance Chemistry, Manufacturing, and Controls Information.'' This guidance provides recommendations on the chemistry, manufacturing, and controls (CMC) information for drug substances that should be...

  3. Hydrocarbon emissions characterization in the Colorado Front Range: A pilot study

    NASA Astrophysics Data System (ADS)

    Pétron, Gabrielle; Frost, Gregory; Miller, Benjamin R.; Hirsch, Adam I.; Montzka, Stephen A.; Karion, Anna; Trainer, Michael; Sweeney, Colm; Andrews, Arlyn E.; Miller, Lloyd; Kofler, Jonathan; Bar-Ilan, Amnon; Dlugokencky, Ed J.; Patrick, Laura; Moore, Charles T., Jr.; Ryerson, Thomas B.; Siso, Carolina; Kolodzey, William; Lang, Patricia M.; Conway, Thomas; Novelli, Paul; Masarie, Kenneth; Hall, Bradley; Guenther, Douglas; Kitzis, Duane; Miller, John; Welsh, David; Wolfe, Dan; Neff, William; Tans, Pieter

    2012-02-01

    The multispecies analysis of daily air samples collected at the NOAA Boulder Atmospheric Observatory (BAO) in Weld County in northeastern Colorado since 2007 shows highly correlated alkane enhancements caused by a regionally distributed mix of sources in the Denver-Julesburg Basin. To further characterize the emissions of methane and non-methane hydrocarbons (propane, n-butane, i-pentane, n-pentane and benzene) around BAO, a pilot study involving automobile-based surveys was carried out during the summer of 2008. A mix of venting emissions (leaks) of raw natural gas and flashing emissions from condensate storage tanks can explain the alkane ratios we observe in air masses impacted by oil and gas operations in northeastern Colorado. Using the WRAP Phase III inventory of total volatile organic compound (VOC) emissions from oil and gas exploration, production and processing, together with flashing and venting emission speciation profiles provided by State agencies or the oil and gas industry, we derive a range of bottom-up speciated emissions for Weld County in 2008. We use the observed ambient molar ratios and flashing and venting emissions data to calculate top-down scenarios for the amount of natural gas leaked to the atmosphere and the associated methane and non-methane emissions. Our analysis suggests that the emissions of the species we measured are most likely underestimated in current inventories and that the uncertainties attached to these estimates can be as high as a factor of two.

  4. An examination of past and present influences on university chemistry education

    NASA Astrophysics Data System (ADS)

    Soliman, William Atef

    This study examined the historical influences that have contributed to past and present-day university level chemistry education. The study was organized into three sections: First, by analyzing the academic genealogy, education origins of prominent chemists, Nobel Prize winners in chemistry and scientific patents awarded by countries; the major historical contributors to chemical education during the 19th century were identified; Secondly, by analyzing the educational backgrounds of current chemistry professors (n=12,120) in 407 universities in 40 countries around the world and six chemical education indicators for 25 countries; and finally the relationship, if any, between a country's chemical, biotechnology, defense, and petroleum industries to its level of chemistry education was investigated utilizing a multiple regression analysis between the monetary value of the industries and the extent of chemical education within each country. The findings indicated that the U.S., Britain, Germany, and France were major influencers of 19th century chemical education while the major present-day influencers of university chemical education are the U.S., Germany, Britain, France, Italy, and Japan. Pearson correlation coefficients indicated that the value of the chemical industry for a country was significantly related to (a) the number of chemistry doctorates awarded (p=.05), (b) chemistry Nobel awards (p=.001), (c) the number of chemistry publications (p=.001), and (d) prominence of the country in the chemical literature (p=.05). Multiple regression analysis indicated that the value of the biotechnology industry was significantly related to the number of Nobel awards (p=.007) and the number of chemistry publications (p=.001). The value of the defense industry was significantly related to chemistry doctorates (p=.002), chemistry Nobel awards (p=.001), the number of chemistry publications (p=.001), and prominence in the literature (p=.001). The value of the petroleum industry was not significantly related to any education variables. The findings suggest that university chemical education is influenced by a select group of countries and that chemical, biotechnology, and defense industry values are significantly related to the level of a country's chemical education. These findings may be valuable to those interested in the industrial and societal applications of chemical education.

  5. Analysis of the Properties of Working Substances for the Organic Rankine Cycle based Database "REFPROP"

    NASA Astrophysics Data System (ADS)

    Galashov, Nikolay; Tsibulskiy, Svyatoslav; Serova, Tatiana

    2016-02-01

    The object of the study are substances that are used as a working fluid in systems operating on the basis of an organic Rankine cycle. The purpose of research is to find substances with the best thermodynamic, thermal and environmental properties. Research conducted on the basis of the analysis of thermodynamic and thermal properties of substances from the base "REFPROP" and with the help of numerical simulation of combined-cycle plant utilization triple cycle, where the lower cycle is an organic Rankine cycle. Base "REFPROP" describes and allows to calculate the thermodynamic and thermophysical parameters of most of the main substances used in production processes. On the basis of scientific publications on the use of working fluids in an organic Rankine cycle analysis were selected ozone-friendly low-boiling substances: ammonia, butane, pentane and Freon: R134a, R152a, R236fa and R245fa. For these substances have been identified and tabulated molecular weight, temperature of the triple point, boiling point, at atmospheric pressure, the parameters of the critical point, the value of the derivative of the temperature on the entropy of the saturated vapor line and the potential ozone depletion and global warming. It was also identified and tabulated thermodynamic and thermophysical parameters of the steam and liquid substances in a state of saturation at a temperature of 15 °C. This temperature is adopted as the minimum temperature of heat removal in the Rankine cycle when working on the water. Studies have shown that the best thermodynamic, thermal and environmental properties of the considered substances are pentane, butane and R245fa. For a more thorough analysis based on a gas turbine plant NK-36ST it has developed a mathematical model of combined cycle gas turbine (CCGT) triple cycle, where the lower cycle is an organic Rankine cycle, and is used as the air cooler condenser. Air condenser allows stating material at a temperature below 0 °C. Calculation of the parameters of all substances in the model are based on a base "REFPROP". Numerical investigations on this model showed that the highest net efficiency will be at work on pentane. Butane and R245fa have the same net efficiency, for 0.8% lower than pentane. Ammonia has a net efficiency of 2.5% is lower than pentane. CCP net efficiency strongly depends on the condensation temperature of the substance, as for pentane at lower temperature of condensation at 10 °C it is increased by 1%.

  6. Chlor-Alkali Industry: A Laboratory Scale Approach

    ERIC Educational Resources Information Center

    Sanchez-Sanchez, C. M.; Exposito, E.; Frias-Ferrer, A.; Gonzalez-Garaia, J.; Monthiel, V.; Aldaz, A.

    2004-01-01

    A laboratory experiment for students in the last year of degree program in chemical engineering, chemistry, or industrial chemistry is presented. It models the chlor-alkali process, one of the most important industrial applications of electrochemical technology and the second largest industrial consumer of electricity after aluminium industry.

  7. Overview on the history of organofluorine chemistry from the viewpoint of material industry

    PubMed Central

    Okazoe, Takashi

    2009-01-01

    Fluorine (from “le fluor”, meaning “to flow”) is a second row element of Group 17 in the periodic table. When bound to carbon it forms the strongest bond in organic chemistry to give organofluorine compounds. The scientific field treating them, organofluorine chemistry, started before elemental fluorine itself was isolated. Applying the fruits in academia, industrial organofluorine chemistry has developed over 80 years via dramatic changes during World War II. Nowadays, it provides various materials essential for our society. Recently, it utilizes elemental fluorine itself as a reagent for the introduction of fluorine atoms to organic molecules in leading-edge industries. This paper overviews the historical development of organofluorine chemistry especially from the viewpoint of material industry. PMID:19838009

  8. On Study of Teaching Reform of Organic Chemistry Course in Applied Chemical Industry Technology

    NASA Astrophysics Data System (ADS)

    Zhang, Yunshen

    2017-11-01

    with the implementation of new curriculum reform, the education sees great changes in teaching methods. Teaching reform is profound in organic chemistry course in applied chemical industry technology. However, many problems which have never been noticed before occur when reform programs are implemented which harm students’ ability for learning and enthusiasm in side face. This paper proposes reform measures like combining theory and practice, improving professional quality, supplementing professional needs and integrating teaching into life after analyzing organic chemistry course teaching in applied chemical industry technology currently, hoping to play a role of reference for organic chemistry course teaching reform in applied chemical industry technology.

  9. Chemists, Engineers Probe Mutual Problems.

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1980

    1980-01-01

    Summarizes recommendations made in a workshop sponsored by the American Chemical Society concerning issues involving the diverging viewpoints of chemistry and chemical engineering. Includes recommendations regarding curricula, salary differences, and the need to change attitudes of chemistry faculty toward industry and industrial chemistry. (CS)

  10. Organometallic Chemistry and Catalysis in Industry.

    ERIC Educational Resources Information Center

    Parshall, George W.; Putscher, Richard E.

    1986-01-01

    Traces the growth in the industrial usage of organometallic chemistry from 1950 to 1977, pointing out that this growth involved the production of commodity chemicals. Indicates that one of the early successes of organometallic chemistry was the discovery of ethylene polymerization catalysts. (JN)

  11. cis-Bis[2-(1,3-benzothia­zol-2-yl)-1-(4-fluoro­phen­yl)ethen­yl](pentane-2,4-dionato-κ2 O,O′)iridium(III)

    PubMed Central

    Xiao, Guo-Yong; Lei, Peng; Chi, Hai-Jun; Hu, Zhi-Zhi; Li, Xiao

    2009-01-01

    In the title compound, [Ir(C15H9FNS)2(C5H7O2)], the Ir atom is hexa­coordinated by three chelating ligands, with two cyclo­metalated 2-(1,3-benzothia­zol-2-yl)-1-(4-fluoro­phen­yl)ethenyl ligands showing N,C-bidentate coordination and an O,O′-bidenate pentane-2,4-dionate anion, thereby forming a distorted octa­hedral enviroment. PMID:21582377

  12. Neuroprotective effects of Lepidium meyenii (Maca).

    PubMed

    Pino-Figueroa, Alejandro; Nguyen, Diane; Maher, Timothy J

    2010-06-01

    The neuroprotective activity of the plant Lepidium meyenii (Maca) was studied in two experimental models: in vitro and in vivo. Crayfish neurons were pretreated with vehicle or the pentane extract from Maca, subjected to H(2)O(2), and their viability determined microscopically and chemically. A significant concentration-neuroprotective effect relationship was demonstrated. The pentane extract was then administered intravenously to rats prior to and following middle cerebral artery occlusion. While infarct volumes were decreased for the lower dose, higher doses increased infarct volumes compared to controls. These results suggest a potential application of Maca as a neuroprotectant.

  13. Chemical Industry: A New Interdisciplinary Course for Secondary Schools.

    ERIC Educational Resources Information Center

    Nae, Nehemia; And Others

    1980-01-01

    Describes an advanced high school course which incorporates an industrial approach into the chemistry curriculum. Presents three case studies as examples taken from the local chemistry industry--the production of copper, bromine, and plastics. (CS)

  14. Transition boiling heat transfer and the film transition regime

    NASA Technical Reports Server (NTRS)

    Ramilison, J. M.; Lienhard, J. H.

    1987-01-01

    The Berenson (1960) flat-plate transition-boiling experiment has been recreated with a reduced thermal resistance in the heater, and an improved access to those portions of the transition boiling regime that have a steep negative slope. Tests have been made in Freon-113, acetone, benzene, and n-pentane boiling on horizontal flat copper heaters that have been mirror-polished, 'roughened', or teflon-coated. The resulting data reproduce and clarify certain features observed by Berenson: the modest surface finish dependence of boiling burnout, and the influence of surface chemistry on both the minimum heat flux and the mode of transition boiling, for example. A rational scheme of correlation yields a prediction of the heat flux in what Witte and Lienhard (1982) previously identified as the 'film-transition boiling' region. It is also shown how to calculate the heat flux at the boundary between the pure-film, and the film-transition, boiling regimes, as a function of the advancing contact angle.

  15. Microbial removal of alkanes from dilute gaseous waste streams: kinetics and mass transfer considerations.

    PubMed

    Barton, J W; Klasson, K T; Koran, L J; Davison, B H

    1997-01-01

    Treatment of dilute gaseous hydrocarbon waste streams remains a current need for many industries, particularly as increasingly stringent environmental regulations and oversight force emission reduction. Biofiltration systems hold promise for providing low-cost alternatives to more traditional, energy-intensive treatment methods such as incineration and adsorption. Elucidation of engineering principles governing the behavior of such systems, including mass transfer limitations, will broaden their applicability. Our processes exploit a microbial consortium to treat a mixture of 0.5% n-pentane and 0.5% isobutane in air. Since hydrocarbon gases are sparingly soluble in water, good mixing and high surface area between the gas and liquid phases are essential for biodegradation to be effective. One liquid-continuous columnar bioreactor was operated for more than 30 months with continued degradation of n-pentane and isobutane as sole carbon and energy sources. The maximum degradation rate observed in this gas-recycle system was 2 g of volatile organic compounds (VOC)/(m3.h). A trickle-bed bioreactor was operated continuously for over 24 months to provide a higher surface area (using a structured packing) with increased rates. Degradation rates consistently achieved were approximately 50 g of VOC/(m3.h) via single pass in this gas-continuous columnar system. Effective mass transfer coefficients comparable to literature values were also measured for this reactor; these values were substantially higher than those found in the gas-recycle reactor. Control of biomass levels was implemented by limiting the level of available nitrogen in the recirculating aqueous media, enabling long-term stability of reactor performance.

  16. 75 FR 36421 - Draft Guidance for Industry on Chemistry, Manufacturing, and Controls Postapproval Manufacturing...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-25

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2010-D-0283] Draft Guidance for Industry on Chemistry, Manufacturing, and Controls Postapproval Manufacturing Changes... guidance describes chemistry, manufacturing, and controls (CMC) postapproval manufacturing changes that FDA...

  17. Basic Chemistry for the Cement Industry.

    ERIC Educational Resources Information Center

    Turner, Mason

    This combined student workbook and instructor's guide contains nine units for inplant classes on basic chemistry for employees in the cement industry. The nine units cover the following topics: chemical basics; measurement; history of cement; atoms; bonding and chemical formulas; solids, liquids, and gases; chemistry of Portland cement…

  18. 1,4-hydroxycarbonyl products of the OH radical initiated reactions of C5-C8 n-alkanes in the presence of NO.

    PubMed

    Reisen, Fabienne; Aschmann, Sara M; Atkinson, Roger; Arey, Janet

    2005-06-15

    Alkanes account for approximately 50% of nonmethane organic compounds present in urban atmospheres. Previous studies have shown that hydroxycarbonyls are important products ofthe OH radical initiated reactions of > or = C5 n-alkanes, but isomer-specific identifications and quantifications of these products have not been carried out. In this work, we have used solid-phase microextraction fibers precoated with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine for on-fiber derivatization of carbonyl-containing compounds with subsequent analyses by combined gas chromatography-mass spectrometry (GC-MS) and GC with flame ionization detection (GC-FID). GC-MS analyses showed the presence of the oximes of 5-hydroxy-2-pentanone and 4-hydroxypentanal from the n-pentane reaction; 5-hydroxy-2-hexanone, 6-hydroxy-3-hexanone, and 4-hydroxyhexanal from the n-hexane reaction; 5-hydroxy-2-heptanone, 6-hydroxy-3-heptanone, 1-hydroxy-4-heptanone, and 4-hydroxyheptanal from the n-heptane reaction; and 5-hydroxy-2-octanone, 6-hydroxy-3-octanone, 7-hydroxy-4-octanone, and 4-hydroxyoctanal from the n-octane reaction. The formation yields of these 1,4-hydroxycarbonyls were determined from GC-FID analyses. By use of the yields of 1,4-hydroxycarbonyls formed from n-hexane, n-heptane, and n-octane at 50% relative humidity (and those from n-pentane at both 5 and 50% relative humidity), then formation of 1,4-hydroxycarbonyls accounts for 54% of the reaction products from n-pentane, 57% from n-hexane, 51% from n-heptane, and 53% from n-octane. Combined with previously measured yields of carbonyls, alkyl nitrates, and hydroxyalkyl nitrates, we can now accountfor approximately 74-118% of the products formed from the n-pentane through n-octane reactions.

  19. Partners in Chemical Education: Proceedings of the International Conference on Industry - Education Initiatives in Chemistry edited by J. N. Lazonby and D. J. Waddington

    NASA Astrophysics Data System (ADS)

    Harris, Hal

    1997-06-01

    What is the place of industrial chemistry in the curriculum? Since virtually every kind of chemistry is used to produce commercial products, what is the difference between industrial and any other type? Most of the chemists that we educate will work in one of the chemical industries, and the nonmajors in our classes also should understand some of the practical chemistry that makes possible the world in which they live. The chemical industry would like to be respected (or at least not feared) for its essential role in modern societies. All of these threads met at a conference at University of York, whose proceedings were recently published. Every even-numbered year, the IUPAC sponsors a big International Conference on Chemical Education that encompasses the whole gamut of issues and developments in the field. The conference of which this volume is the Proceedings occurred in late summer, 1995, an off year for the big conference, and was designed to attract a smaller audience to a more specific topic. Given the current interest from both the academic and industrial sides of the subject of joint efforts, it is not surprising that the organizers at University of York were able to attract a sizable number of participants and a page full of industrial donors to what appears to have been a very successful five-day meeting. The Proceedings are organized into Plenary Lectures, Symposia, Workshops, and Poster Papers, but the conference itself included displays, industrial visits, informal events, and other activities that could not be captured on paper. The Plenary Lectures included contributions from both the industry and academic speakers, as well as three lectures describing Chemistry and Industry Centers, which are enhanced science museums that emphasize the role of the chemical industry. Joost Douma and Astrid van de Graaf (Prototyping for the 21st Century) described plans for such an enterprise (IMPULS), to open in April 1997 in Amsterdam. T. M. Alagiri Swamy Raju briefly summarized India's network of 50 science centers, describing in more detail the Madras Science Center where he works. The Chemical Industry Education Center in York, as described by its Manager, Miranda Mapletoft, seems to have the most extensive program integrating the chemical industry into chemistry classrooms. The Center has been working very closely with the University of York to produce a number of books and pamphlets that are cited in her useful bibliography. Michael Pratt of DuPont Printing and Publishing showed how the chemistry of lithographic printing can be used to teach. Fernando Galembeck and Elizabeth Fatima de Souza came from the Institute of Chemistry of the University of Campinas, Brazil, to show how physical and chemical principles essential to the paints and coatings industry also occur in the chemistry curriculum. More general lectures about industry-education cooperation were presented by keynoter David Giachardi and Ann Hubbard.

  20. Combinatorial computational chemistry approach for materials design: applications in deNOx catalysis, Fischer-Tropsch synthesis, lanthanoid complex, and lithium ion secondary battery.

    PubMed

    Koyama, Michihisa; Tsuboi, Hideyuki; Endou, Akira; Takaba, Hiromitsu; Kubo, Momoji; Del Carpio, Carlos A; Miyamoto, Akira

    2007-02-01

    Computational chemistry can provide fundamental knowledge regarding various aspects of materials. While its impact in scientific research is greatly increasing, its contributions to industrially important issues are far from satisfactory. In order to realize industrial innovation by computational chemistry, a new concept "combinatorial computational chemistry" has been proposed by introducing the concept of combinatorial chemistry to computational chemistry. This combinatorial computational chemistry approach enables theoretical high-throughput screening for materials design. In this manuscript, we review the successful applications of combinatorial computational chemistry to deNO(x) catalysts, Fischer-Tropsch catalysts, lanthanoid complex catalysts, and cathodes of the lithium ion secondary battery.

  1. Solidification and loss of hydrostaticity in liquid media used for pressure measurements

    DOE PAGES

    Torikachvili, M. S.; Kim, S. K.; Colombier, E.; ...

    2015-12-16

    We carried out a study of the pressure dependence of the solidification temperature in nine pressure transmitting media that are liquid at ambient temperature, under pressures up to 2.3 GPa. These fluids are 1:1 isopentane/n-pentane, 4:6 light mineral oil/n-pentane, 1:1 isoamyl alcohol/n-pentane, 4:1 methanol/ethanol, 1:1 FC72/FC84 (Fluorinert), Daphne 7373, isopentane, and Dow Corning PMX silicone oils 200 and 60,000 cS. We relied on the high sensitivity of the electrical resistivity of Ba(Fe 1–xRu x) 2As 2 single crystals to the freezing of the pressure media and cross-checked with corresponding anomalies observed in the resistance of the manganin coil that servedmore » as the ambient temperature resistive manometer. In addition to establishing the temperature-pressure line separating the liquid (hydrostatic) and frozen (non-hydrostatic) phases, these data permit rough estimates of the freezing pressure of these media at ambient temperature. As a result, this pressure establishes the extreme limit for the medium to be considered hydrostatic. For higher applied pressures, the medium has to be treated as non-hydrostatic.« less

  2. Solidification and loss of hydrostaticity in liquid media used for pressure measurements

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Torikachvili, M. S.; Kim, S. K.; Colombier, E.

    We carried out a study of the pressure dependence of the solidification temperature in nine pressure transmitting media that are liquid at ambient temperature, under pressures up to 2.3 GPa. These fluids are 1:1 isopentane/n-pentane, 4:6 light mineral oil/n-pentane, 1:1 isoamyl alcohol/n-pentane, 4:1 methanol/ethanol, 1:1 FC72/FC84 (Fluorinert), Daphne 7373, isopentane, and Dow Corning PMX silicone oils 200 and 60,000 cS. We relied on the high sensitivity of the electrical resistivity of Ba(Fe 1–xRu x) 2As 2 single crystals to the freezing of the pressure media and cross-checked with corresponding anomalies observed in the resistance of the manganin coil that servedmore » as the ambient temperature resistive manometer. In addition to establishing the temperature-pressure line separating the liquid (hydrostatic) and frozen (non-hydrostatic) phases, these data permit rough estimates of the freezing pressure of these media at ambient temperature. As a result, this pressure establishes the extreme limit for the medium to be considered hydrostatic. For higher applied pressures, the medium has to be treated as non-hydrostatic.« less

  3. Air quality in the Industrial Heartland of Alberta, Canada and potential impacts on human health

    NASA Astrophysics Data System (ADS)

    Simpson, Isobel J.; Marrero, Josette E.; Batterman, Stuart; Meinardi, Simone; Barletta, Barbara; Blake, Donald R.

    2013-12-01

    The “Industrial Heartland” of Alberta is Canada's largest hydrocarbon processing center, with more than 40 major chemical, petrochemical, and oil and gas facilities. Emissions from these industries affect local air quality and human health. This paper characterizes ambient levels of 77 volatile organic compounds (VOCs) in the region using high-precision measurements collected in summer 2010. Remarkably strong enhancements of 43 VOCs were detected, and concentrations in the industrial plumes were often similar to or even higher than levels measured in some of the world's largest cities and industrial regions. For example maximum levels of propene and i-pentane exceeded 100 ppbv, and 1,3-butadiene, a known carcinogen, reached 27 ppbv. Major VOC sources included propene fractionation, diluent separation and bitumen processing. Emissions of the measured VOCs increased the hydroxyl radical reactivity (kOH), a measure of the potential to form downwind ozone, from 3.4 s-1 in background air to 62 s-1 in the most concentrated plumes. The plume value was comparable to polluted megacity values, and acetaldehyde, propene and 1,3-butadiene contributed over half of the plume kOH. Based on a 13-year record (1994-2006) at the county level, the incidence of male hematopoietic cancers (leukemia and non-Hodgkin lymphoma) was higher in communities closest to the Industrial Heartland compared to neighboring counties. While a causal association between these cancers and exposure to industrial emissions cannot be confirmed, this pattern and the elevated VOC levels warrant actions to reduce emissions of known carcinogens, including benzene and 1,3-butadiene.

  4. Air quality in the Industrial Heartland of Alberta, Canada and potential impacts on human health

    PubMed Central

    Simpson, Isobel J.; Marrero, Josette E.; Batterman, Stuart; Meinardi, Simone; Barletta, Barbara; Blake, Donald R.

    2015-01-01

    The “Industrial Heartland” of Alberta is Canada’s largest hydrocarbon processing center, with more than 40 major chemical, petrochemical, and oil and gas facilities. Emissions from these industries affect local air quality and human health. This paper characterizes ambient levels of 77 volatile organic compounds (VOCs) in the region using high-precision measurements collected in summer 2010. Remarkably strong enhancements of 43 VOCs were detected, and concentrations in the industrial plumes were often similar to or even higher than levels measured in some of the world’s largest cities and industrial regions. For example maximum levels of propene and i-pentane exceeded 100 ppbv, and 1,3-butadiene, a known carcinogen, reached 27 ppbv. Major VOC sources included propene fractionation, diluent separation and bitumen processing. Emissions of the measured VOCs increased the hydroxyl radical reactivity (kOH), a measure of the potential to form downwind ozone, from 3.4 s−1 in background air to 62 s−1 in the most concentrated plumes. The plume value was comparable to polluted megacity values, and acetaldehyde, propene and 1,3-butadiene contributed over half of the plume kOH. Based on a 13-year record (1994–2006) at the county level, the incidence of male hematopoietic cancers (leukemia and non-Hodgkin lymphoma) was higher in communities closest to the Industrial Heartland compared to neighboring counties. While a causal association between these cancers and exposure to industrial emissions cannot be confirmed, this pattern and the elevated VOC levels warrant actions to reduce emissions of known carcinogens, including benzene and 1,3-butadiene. PMID:25685050

  5. Observations and Explicit Modeling of Summertime Carbonyl Formation in Beijing: Identification of Key Precursor Species and Their Impact on Atmospheric Oxidation Chemistry

    NASA Astrophysics Data System (ADS)

    Yang, Xue; Xue, Likun; Wang, Tao; Wang, Xinfeng; Gao, Jian; Lee, Shuncheng; Blake, Donald R.; Chai, Fahe; Wang, Wenxing

    2018-01-01

    Carbonyls are an important group of volatile organic compounds (VOCs) that play critical roles in tropospheric chemistry. To better understand the formation mechanisms of carbonyl compounds, extensive measurements of carbonyls and related parameters were conducted in Beijing in summer 2008. Formaldehyde (11.17 ± 5.32 ppbv), acetone (6.98 ± 3.01 ppbv), and acetaldehyde (5.27 ± 2.24 ppbv) were the most abundant carbonyl species. Two dicarbonyls, glyoxal (0.68 ± 0.26 ppbv) and methylglyoxal (MGLY; 1.10 ± 0.44 ppbv), were also present in relatively high concentrations. An observation-based chemical box model was used to simulate the in situ production of formaldehyde, acetaldehyde, glyoxal, and MGLY and quantify their contributions to ozone formation and ROx budget. All four carbonyls showed similar formation mechanisms but exhibited different precursor distributions. Alkenes (mainly isoprene and ethene) were the dominant precursors of formaldehyde, while both alkenes (e.g., propene, i-butene, and cis-2-pentene) and alkanes (mainly i-pentane) were major precursors of acetaldehyde. For dicarbonyls, both isoprene and aromatic VOCs were the dominant parent hydrocarbons of glyoxal and MGLY. Photolysis of oxygenated VOCs was the dominant source of ROx radicals (approximately >80% for HO2 and approximately >70% for RO2) in Beijing. Ozone production occurred under a mixed-control regime with carbonyls being the key VOC species. Overall, this study provides some new insights into the formation mechanisms of carbonyls, especially their parent hydrocarbon species, and underlines the important role of carbonyls in radical chemistry and ozone pollution in Beijing. Reducing the emissions of alkenes and aromatics would be an effective way to mitigate photochemical pollution in Beijing.

  6. Synthesis, Isolation, and Characterization of Dimeric Compounds Containing Two Different Exocyclic Ligands on the Group 13 Center. X-Ray Crystal Structures of R(Me3SiCH2)InE(SiMe3)22 (R=Ph, E=As; R=Me, E=As, P; R=Cl, E-P)

    DTIC Science & Technology

    1992-09-07

    from the resulting light yellow solution, leaving a viscous yellow oil . This oil was dissolved in pentane and upon storing at -15 °C for 1 week...to 40* C in an oil bath and allowed to stir for 5 days. The volatiles were removed in vacuo leaving a powdery white residue. The residue was dissolved...from the resulting cloudy yellow solution, leaving a milky yellow oil . The oil was dissolved in pentane and allowed to evaporate slowly at room

  7. Structure of α, ω-bis-(pentane-2,4-dione-3-ylmethylsulfanyl)alkanes and even/odd crystallization effects

    NASA Astrophysics Data System (ADS)

    Khalilov, Leonard M.; Tulyabaev, Arthur R.; Mescheryakova, Ekaterina S.; Akhmadiev, Nail S.; Timirov, Yulai I.; Skaldin, Oleg A.; Akhmetova, Vnira R.

    2015-09-01

    The relationships between structural features and crystallization of the С1-С6 α,ω-bis-(pentane-2,4-dione-3-ylmethylsulfanyl)alkanes are considered. It was shown that the conjugated enol bis-pentadiones which form pseudo six-membered rings and stabilized by intramolecular hydrogen bonds favor the crystallization. Using a polarized optical technique, it has been found that crystallization rate of the melts of crystalline compounds decreases with elongation of the aliphatic chain between sulfur atoms. It is assumed that one of the main factors that contributes to probability to form single crystals is a small twist angle between two pseudo six-membered rings.

  8. Anthropogenic emissions of nonmethane hydrocarbons in the northeastern United States: Measured seasonal variations from 1992-1996 and 1999-2001

    NASA Astrophysics Data System (ADS)

    Lee, Ben H.; Munger, J. William; Wofsy, Steven C.; Goldstein, Allen H.

    2006-10-01

    Harvard Forest, a rural site located in central Massachusetts downwind of major urban-industrial centers, provides an excellent location to observe a typical regional mixture of anthropogenic trace gases. Air that arrives at Harvard Forest from the southwest is affected by emissions from the U.S. east coast urban corridor and may have residual influence from emissions in the upper Ohio Valley and Great Lakes region farther to the west. Because of its relatively long distance from large individual emission sources, pollution plumes reaching the site are a homogenized mixture of regional anthropogenic emissions. Concentrations of C2-C6 hydrocarbons along with CO and NOy were measured nearly continuously from August 1992 through July 1996 and from June 1999 through November 2001. By correlating observed concentrations to acetylene, which is almost solely produced during combustion, we are able to detect seasonal trends in relative emissions for this series of trace gases. Seasonal changes in n-butane and i-butane emissions may largely be influenced by different gasoline formulations in late spring and summer. Shifts in evaporation rates due to the annual temperature cycle could induce a seasonal pattern for n-pentane, i-pentane and n-hexane emissions. Emissions of ethane and propane lack clear seasonality relative to acetylene emissions and also correlate less with acetylene than other gases, indicating that emissions of these two gases are strongly influenced by sources not associated with fuel combustion. Changes in the observed correlations of CO2 and CO relative to acetylene are consistent with published changes in the estimated emissions of CO2 and CO over the past decade, though variability in the observations makes it difficult to precisely quantify these changes.

  9. Do vehicular emissions dominate the source of C6-C8 aromatics in the megacity Shanghai of eastern China?

    PubMed

    Wang, Hongli; Wang, Qian; Chen, Jianmin; Chen, Changhong; Huang, Cheng; Qiao, Liping; Lou, Shengrong; Lu, Jun

    2015-01-01

    The characteristic ratios of volatile organic compounds (VOCs) to i-pentane, the indicator of vehicular emissions, were employed to apportion the vehicular and non-vehicular contributions to reactive species in urban Shanghai. Two kinds of tunnel experiments, one tunnel with more than 90% light duty gasoline vehicles and the other with more than 60% light duty diesel vehicles, were carried out to study the characteristic ratios of vehicle-related emissions from December 2009 to January 2010. Based on the experiments, the characteristic ratios of C6-C8 aromatics to i-pentane of vehicular emissions were 0.53 ± 0.08 (benzene), 0.70 ± 0.12 (toluene), 0.41 ± 0.09 (m,p-xylenes), 0.16 ± 0.04 (o-xylene), 0.023 ± 0.011 (styrene), and 0.15 ± 0.02 (ethylbenzene), respectively. The source apportionment results showed that around 23.3% of C6-C8 aromatics in urban Shanghai were from vehicular emissions, which meant that the non-vehicular emissions had more importance. These findings suggested that emission control of non-vehicular sources, i.e. industrial emissions, should also receive attention in addition to the control of vehicle-related emissions in Shanghai. The chemical removal of VOCs during the transport from emissions to the receptor site had a large impact on the apportionment results. Generally, the overestimation of vehicular contributions would occur when the VOC reaction rate constant with OH radicals (kOH) was larger than that of the vehicular indicator, while for species with smaller kOH than the vehicular indicator, the vehicular contribution would be underestimated by the method of characteristic ratios. Copyright © 2014. Published by Elsevier B.V.

  10. An Alternative Educational Approach for an Inorganic Chemistry Laboratory Course in Industrial and Chemical Engineering

    ERIC Educational Resources Information Center

    Garces, Andres; Sanchez-Barba, Luis Fernando

    2011-01-01

    We describe an alternative educational approach for an inorganic chemistry laboratory module named "Experimentation in Chemistry", which is included in Industrial Engineering and Chemical Engineering courses. The main aims of the new approach were to reduce the high levels of failure and dropout on the module and to make the content match the…

  11. The quadruple bottom line: the advantages of incorporating Green Chemistry into the undergraduate chemistry major

    NASA Astrophysics Data System (ADS)

    Bodner, George M.

    2017-08-01

    When the author first became involved with the Green Chemistry movement, he noted that his colleagues in industry who were involved in one of the ACS Green Chemistry Institute® industrial roundtables emphasized the take-home message they described as the "triple bottom line." They noted that introducing Green Chemistry in industrial settings had economic, social, and environmental benefits. As someone who first went to school at age 5, and has been "going to school" most days for 65 years, it was easy for the author to see why introducing Green Chemistry into academics had similar beneficial effects within the context of economic, social and environmental domains at the college/university level. He was prepared to understand why faculty who had taught traditional courses often saw the advantage of incorporating Green Chemistry into the courses they teach. What was not as obvious is why students who were encountering chemistry for the first time were often equally passionate about the Green Chemistry movement. Recent attention has been paid, however, to a model that brings clarity to the hitherto vague term of "relevance" that might explain why integrating Green Chemistry into the undergraduate chemistry classroom can achieve a "quadruple bottom-line" for students because of potentially positive effects of adding a domain of "relevance" to the existing economic, social, and environmental domains.

  12. Theoretical and Experimental Investigation of the Stability of an Evaporating Constrained Vapor Bubble

    NASA Technical Reports Server (NTRS)

    Wayner, P. C., Jr.; Plawsky, J. L.; Wong, Harris

    2004-01-01

    The major accomplishments of the experimental portion of the research were documented in Ling Zheng's doctoral dissertation. Using Pentane, he obtained a considerable amount of data on the stability and heat transfer characteristics of an evaporating meniscus. The important points are that experimental equipment to obtain data on the stability and heat transfer characteristics of an evaporating meniscus were built and successfully operated. The data and subsequent analyses were accepted by the Journal of Heat Transfer for publication in 2004 [PU4]. The work was continued by a new graduate student using HFE-7000 [PU3] and then Pentane at lower heat fluxes. The Pentane results are being analyzed for publication. The experimental techniques are currently being used in our other NASA Grant. The oscillation of the contact line observed in the experiments involves evaporation (retraction part) and spreading. Since both processes occur with finite contact angles, it is important to derive a precise equation of the intermolecular forces (disjoining pressure) valid for non-zero contact angles. This theoretical derivation was accepted for publication by Journal of Fluid Mechanics [PU5]. The evaporation process near the contact line is complicated, and an idealized micro heat pipe has been proposed to help in elucidating the detailed evaporation process [manuscripts in preparation].

  13. An Industrial Chemistry Course that Optimizes the Value of Plant Tours

    ERIC Educational Resources Information Center

    Hartman, J. Stephen

    2005-01-01

    Plant tours, when emphasized appropriately and fully integrated into an industrial chemistry course, are very useful in motivating students and deepening their understanding of the chemical industry. Emphasis is placed on plant tours as it adds immediacy and a practical flavor to the course and is a good preparation for the graduates who move from…

  14. Cometabolism of Methyl tertiary Butyl Ether and Gaseous n-Alkanes by Pseudomonas mendocina KR-1 Grown on C5 to C8 n-Alkanes

    PubMed Central

    Smith, Christy A.; O'Reilly, Kirk T.; Hyman, Michael R.

    2003-01-01

    Pseudomonas mendocina KR-1 grew well on toluene, n-alkanes (C5 to C8), and 1° alcohols (C2 to C8) but not on other aromatics, gaseous n-alkanes (C1 to C4), isoalkanes (C4 to C6), 2° alcohols (C3 to C8), methyl tertiary butyl ether (MTBE), or tertiary butyl alcohol (TBA). Cells grown under carbon-limited conditions on n-alkanes in the presence of MTBE (42 μmol) oxidized up to 94% of the added MTBE to TBA. Less than 3% of the added MTBE was oxidized to TBA when cells were grown on either 1° alcohols, toluene, or dextrose in the presence of MTBE. Concentrated n-pentane-grown cells oxidized MTBE to TBA without a lag phase and without generating tertiary butyl formate (TBF) as an intermediate. Neither TBF nor TBA was consumed by n-pentane-grown cells, while formaldehyde, the expected C1 product of MTBE dealkylation, was rapidly consumed. Similar Ks values for MTBE were observed for cells grown on C5 to C8 n-alkanes (12.95 ± 2.04 mM), suggesting that the same enzyme oxidizes MTBE in cells grown on each n-alkane. All growth-supporting n-alkanes (C5 to C8) inhibited MTBE oxidation by resting n-pentane-grown cells. Propane (Ki = 53 μM) and n-butane (Ki = 16 μM) also inhibited MTBE oxidation, and both gases were also consumed by cells during growth on n-pentane. Cultures grown on C5 to C8 n-alkanes also exhibited up to twofold-higher levels of growth in the presence of propane or n-butane, whereas no growth stimulation was observed with methane, ethane, MTBE, TBA, or formaldehyde. The results are discussed in terms of their impacts on our understanding of MTBE biodegradation and cometabolism. PMID:14660389

  15. Wild carrot pentane-based fractions suppress proliferation of human HaCaT keratinocytes and protect against chemically-induced skin cancer.

    PubMed

    Shebaby, Wassim N; Mroueh, Mohamad A; Boukamp, Petra; Taleb, Robin I; Bodman-Smith, Kikki; El-Sibai, Mirvat; Daher, Costantine F

    2017-01-10

    Previous studies in our laboratory showed that the Lebanese Daucus carota ssp. carota (wild carrot) oil extract possesses in vitro and in vivo anticancer activities. The present study aims to examine the cytotoxic effect of Daucus carota oil fractions on human epidermal keratinocytes and evaluate the chemopreventive activity of the pentane diethyl ether fraction on DMBA/TPA induced skin carcinogenesis in mice. Wild carrot oil extract was chromatographed to yield four fractions (F1, 100% pentane; F2, 50:50 pentane:diethyl ether; F3, 100% diethyl ether; F4 93:7 chloroform:methanol). The cytotoxic effect of fractions (10, 25, 50 and 100 μg/mL) was tested on human epidermal keratinocytes (non-tumorigenic HaCaT cells and tumorigenic HaCaT-ras variants) using WST a ssay. Cell cycle phase distribution of tumorigenic HaCaT-ras variants was determined by flow cytometry post-treatment with F2 fraction. Apoptosis related proteins were also assessed using western blot. The antitumor activity of F2 fraction was also evaluated using a DMBA/TPA induced skin carcinoma in Balb/c mice. All fractions exhibited significant cytotoxicity, with HaCaT cells being 2.4-3 times less sensitive than HaCaT-ras A5 (benign tumorigenic), and HaCaT-ras II4 (malignant) cells. GC-MS analysis revealed the presence of a major compound (around 60%) in the pentane/diethylether fraction (F2), identified as 2-himachalen-6-ol. Treatment of HaCaT-ras A5 and HaCaT-ras II4 cells with F2 fraction resulted in the accumulation of cells in the sub-G1 apoptotic phase and decreased the population of cells in the S and G2/M phases. Additionally, F2 fraction treatment caused an up-regulation of the expression of pro-apoptotic (Bax) and down-regulation of the expression of anti-apoptotic (Bcl2) proteins. A decrease in the phosphorylation of AKT and ERK was also observed. Intraperitoneal treatment with F2 fraction (50 or 200 mg/kg) in the DMBA/TPA skin carcinogenesis mouse model showed a significant inhibition of papilloma incidence (mice with papilloma), yield (number of papilloma/mouse) and volume (tumor relative size) at weeks 15, 18 and 21. The present data reveal that F2 fraction has a remarkable antitumor activity against DMBA/TPA-induced skin carcinogenesis, an effect that may be mediated through inhibition of the MAPK/ERK and PI3K/AKT pathways.

  16. Summer Course Promotes Polymer Chemistry for Small Colleges.

    ERIC Educational Resources Information Center

    Stinson, Stephen

    1989-01-01

    Describes a three-week summer program teaching selected chemistry faculty how to incorporate polymer chemistry into chemistry courses. In addition to lectures, the program conducted many experiments and provided a trip to industry laboratories. (YP)

  17. Teaching Applied Chemistry in a Pollution Control Context.

    ERIC Educational Resources Information Center

    Sell, Nancy J.

    1982-01-01

    Discusses rationale behind and content of a course (Industrial Pollution Control Techniques) combining knowledge from fields of industrial chemistry and chemical engineering and utilizing this knowledge in the context of understanding pollution problems and potential methods of pollution control. (Author/SK)

  18. Safety in the Chemical Laboratory

    ERIC Educational Resources Information Center

    Steere, Norman V., Ed.

    1974-01-01

    Discusses the offering of a course in chemical and industrial hazards for junior and senior chemistry majors at City College of New York in 1972. Suggests inclusion of laboratory and industrial safety education as a formal part of chemistry or science curricula. (CC)

  19. Kent and Riegel's Handbook of industrial chemistry and biotechnology. 11th ed.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kent, James A.

    2007-07-01

    This handbook provides extensive information on plastics, rubber, adhesives, textile fibers, pharmaceutical chemistry, synthetic organic chemicals, soaps and detergents, as well as various other major classes of industrial chemistry. There is detailed coverage of coal utilization technology, dyes and dye intermediates, chlor-alkali and heavy chemicals, paints and pigments, chemical explosives, propellants, petroleum and petrochemicals, natural gas, industrial gases, synthetic nitrogen products, fats and oils, sulfur and sulfuric acid, phosphorous and phosphates, wood products, and sweeteners. The chapter on coal is entitled: coal technology for power, liquid fuels and chemicals. 100 ills.

  20. Removal of Cyclohexane from a Contaminated Air Stream Using a Dense Phase Membrane Bioreactor

    DTIC Science & Technology

    2005-03-01

    57 Statistical Analysis ....................................................................................................57...60 JP-8 Analysis , Transfer, and...Challenges ..................................................................60 n-Pentane Analysis , Transfer, and Challenges

  1. Gas-liquid chromatographic determination of resmethrin in corn, cornmeal, flour, and wheat.

    PubMed

    Simonaitis, R A; Cail, R S

    1975-09-01

    A gas-liquid chromatographic (GLC) method was developed for the determination of residues of resmethrin ((5-benzyl-3-furyl)methyl cis-trans-(+/-)-2,2-dimethyl-3-(2-methylpropenyl)-cyclopropanecarboxylate) in corn, cornmeal, flour, and wheat. The commodity, fortified with resmethrin, was extracted by tumbling with pentane and transferred to acetonitrile, the fat was partitioned off, and the sample was chromatographed with 3% ethyl acetate in pentane on Florisil containing 0.5% water. The resmethrin residue was determined by GLC with a flame ionization detector. The results were compared with known standards that had undergone the same cleanup procedures. The method was sensitive to concentrations of resmethrin to 0.2 ppm, recoveries averaged 83%, and reproducibility was good.

  2. 77 FR 14022 - Guidance for Industry on Chemistry, Manufacturing, and Controls Information-Fermentation-Derived...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-08

    ...] Guidance for Industry on Chemistry, Manufacturing, and Controls Information--Fermentation-Derived... (CMC) Information-- Fermentation-Derived Intermediates, Drug Substances, and Related Drug Products for... to submit to support the CMC information for fermentation-derived intermediates, drug substances, and...

  3. 31 CFR 561.319 - Petroleum products.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... petroleum gases, pentanes plus, aviation gasoline, motor gasoline, naphtha-type jet fuel, kerosene-type jet fuel, kerosene, distillate fuel oil, residual fuel oil, petrochemical feedstocks, special naphthas...

  4. 31 CFR 561.319 - Petroleum products.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... petroleum gases, pentanes plus, aviation gasoline, motor gasoline, naphtha-type jet fuel, kerosene-type jet fuel, kerosene, distillate fuel oil, residual fuel oil, petrochemical feedstocks, special naphthas...

  5. 31 CFR 561.319 - Petroleum products.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... petroleum gases, pentanes plus, aviation gasoline, motor gasoline, naphtha-type jet fuel, kerosene-type jet fuel, kerosene, distillate fuel oil, residual fuel oil, petrochemical feedstocks, special naphthas...

  6. 76 FR 13629 - Draft Guidance for Industry on Chemistry, Manufacturing, and Controls Information-Fermentation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-14

    ...] Draft Guidance for Industry on Chemistry, Manufacturing, and Controls Information--Fermentation-Derived... Controls (CMC) Information-- Fermentation-Derived Intermediates, Drug Substances, and Related Drug Products... documentation to submit to support the CMC information for fermentation-derived intermediates, drug substances...

  7. International comparison CCQM-K119 liquefied petroleum gas

    NASA Astrophysics Data System (ADS)

    Brewer, P. J.; Downey, M. L.; Atkins, E.; Brown, R. J. C.; Brown, A. S.; Zalewska, E. T.; van der Veen, A. M. H.; Smeulders, D. E.; McCallum, J. B.; Satumba, R. T.; Kim, Y. D.; Kang, N.; Bae, H. K.; Woo, J. C.; Konopelko, L. A.; Popova, T. A.; Meshkov, A. V.; Efremova, O. V.; Kustikov, Y.

    2018-01-01

    Liquefied hydrocarbon mixtures with traceable composition are required in order to underpin measurements of the composition and other physical properties of LPG (liquefied petroleum gas), thus meeting the needs of an increasingly large industrial market. This comparison aims to assess the analytical capabilities of laboratories for measuring the composition of a Liquid Petroleum Gas (LPG) mixture when sampled in the liquid phase from a Constant Pressure Cylinder. Mixtures contained ethane, propane, propene, i-butane, n-butane, but-1-ene and i-pentane with nominal amount fractions of 2, 71, 9, 4, 10, 3 and 1 cmol mol-1 respectively. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  8. Suppression of reaction during rapid compression and its effect on ignition delay

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mohamed, C.

    1998-02-01

    A single-shot, rapid compression machine has been used to investigate the effect of diethylamine (5 mol%) on the spontaneous ignition (or autoignition) of n-heptane and n-pentane in stoichiometric proportion in air ({psi} = 1.0). Autoignition delays were measured at compressed gas temperatures and pressures in the range 659--950 K and 9--11 atm, respectively. In addition to pressure-time data, the total light output from the chamber was recorded as a function of time using a photomultiplier positioned at the end window. Diethylamine retards the first stage of the two-stage ignition of n-heptane and n-pentane, causing a reduction in both the pressuremore » rise and the light intensity associated with the first (cool flame) stage. A longer duration of the second stage of ignition was measured. Consequently, an increase in ignition delay was observed for n-heptane throughout the temperature range 650--950 K, for which first-stage reactions persist in the compression stroke at temperatures above 850 K. The ignition delay of n-pentane was increased in the range 650--850 K by the addition of diethylamine, but was decreased at compressed gas temperatures greater than 850 K. The possible mechanisms of the inhibition of the first stage of autoignition and promotion of the second stage by diethylamine are outlined.« less

  9. Chromatographic analysis of methylglyoxal and other α-dicarbonyls using gas-diffusion microextraction.

    PubMed

    Santos, Christiane M; Valente, Inês M; Gonçalves, Luís M; Rodrigues, José A

    2013-12-07

    Many α-dicarbonyl compounds such as methylglyoxal, diacetyl and pentane-2,3-dione are important quality markers of processed foods. They are produced by enzymatic and chemical processes, the Maillard reaction is the most known chemical route for α-dicarbonyl formation. In the case of methylglyoxal, there are obstacles to be overcome when analysing this compound due to its high reactivity, low volatility and low concentration. The use of extraction techniques based on the volatilization of methylglyoxal (like solid-phase microextraction) showed to be ineffective for the methylglyoxal extraction from aqueous solutions. Therefore, derivatization is typically applied to increase analyte's volatility. In this work a new methodology for the extraction and analysis of methylglyoxal and also diacetyl and pentane-2,3-dione from selected food matrices is presented. It is based on a gas-diffusion microextraction step followed by high performance liquid chromatographic analysis. It was successfully applied to port wines, black tea and soy sauce. Methylglyoxal, diacetyl and pentane-2,3-dione were quantified in the following concentration ranges: 0.24-1.74 mg L(-1), 0.1-1.85 mg L(-1) and 0.023-0.15 mg L(-1), respectively. The main advantages over existing methodologies are its simplicity in terms of sample handling, not requiring any chemical modification of the α-dicarbonyls prior to the extraction, low reagent consumption and short time of analysis.

  10. 27 CFR 19.746 - Authorized materials.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... benzoate N.F. and 2 gallons of isopropyl alcohol. (c) Specifications. (1) Specifications for gasoline... mixture of butane, pentane, and hexane hydrocarbons extracted from natural gas; and (ii) Distillation...

  11. 27 CFR 19.746 - Authorized materials.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... benzoate N.F. and 2 gallons of isopropyl alcohol. (c) Specifications. (1) Specifications for gasoline... mixture of butane, pentane, and hexane hydrocarbons extracted from natural gas; and (ii) Distillation...

  12. 27 CFR 19.746 - Authorized materials.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... benzoate N.F. and 2 gallons of isopropyl alcohol. (c) Specifications. (1) Specifications for gasoline... mixture of butane, pentane, and hexane hydrocarbons extracted from natural gas; and (ii) Distillation...

  13. 27 CFR 19.746 - Authorized materials.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... benzoate N.F. and 2 gallons of isopropyl alcohol. (c) Specifications. (1) Specifications for gasoline... mixture of butane, pentane, and hexane hydrocarbons extracted from natural gas; and (ii) Distillation...

  14. Chemistry Notes

    ERIC Educational Resources Information Center

    School Science Review, 1972

    1972-01-01

    Thirteen ideas are presented that may be of use to chemistry teachers. Topics covered include vitamin C, industrial chemistry, electrical conductivity, electrolysis, alkali metals, vibration modes infra-red, dynamic equilibrium, and some new demonstrations in gaseous combinations. (PS)

  15. Performance specifications and six sigma theory: Clinical chemistry and industry compared.

    PubMed

    Oosterhuis, W P; Severens, M J M J

    2018-04-11

    Analytical performance specifications are crucial in test development and quality control. Although consensus has been reached on the use of biological variation to derive these specifications, no consensus has been reached which model should be preferred. The Six Sigma concept is widely applied in industry for quality specifications of products and can well be compared with Six Sigma models in clinical chemistry. However, the models for measurement specifications differ considerably between both fields: where the sigma metric is used in clinical chemistry, in industry the Number of Distinct Categories is used instead. In this study the models in both fields are compared and discussed. Copyright © 2018. Published by Elsevier Inc.

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

    ERIC Educational Resources Information Center

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

    2008-01-01

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

  17. Introducing Chemistry Students to the "Real World" of Chemistry

    ERIC Educational Resources Information Center

    Brown, Michael E.; Cosser, Ronald C.; Davies-Coleman, Michael T.; Kaye, Perry T.; Klein, Rosalyn; Lamprecht, Emmanuel; Lobb, Kevin; Nyokong, Tebello; Sewry, Joyce D.; Tshentu, Zenixole R.; van der Zeyde, Tino; Watkins, Gareth M.

    2010-01-01

    A majority of chemistry graduates seek employment in a rapidly changing chemical industry. Our attempts to provide the graduates with skills in entrepreneurship and the ability to understand and communicate with their chemical engineering colleagues, in addition to their fundamental knowledge of chemistry, are described. This is done at…

  18. Partners for Progress and Prosperity in the Global Chemistry Enterprise

    USDA-ARS?s Scientific Manuscript database

    In the past several years, there have been many changes facing the global chemistry enterprise. Whereas the overall chemistry enterprise appears to be strong and the chemical industry is still a major contributor to GDP, many chemistry-based products have been commoditized, and chemical employment h...

  19. Temperature-dependent mid-IR absorption spectra of gaseous hydrocarbons

    NASA Astrophysics Data System (ADS)

    Klingbeil, Adam E.; Jeffries, Jay B.; Hanson, Ronald K.

    2007-10-01

    Quantitative mid-IR absorption spectra (2500 3400 cm-1) for 12 pure hydrocarbon compounds are measured at temperatures ranging from 25 to 500 °C using an FTIR spectrometer. The hydrocarbons studied are n-pentane, n-heptane, n-dodecane, 2,2,4-trimethyl-pentane (iso-octane), 2-methyl-butane, 2-methyl-pentane, 2,4,4-trimethyl-1-pentene, 2-methyl-2-butene, propene, toluene, m-xylene, and ethylbenzene. Room-temperature measurements of neat hydrocarbon vapor were made with an instrument resolution of both 0.1 and 1 cm-1 (FWHM) to confirm that the high-resolution setting was required only to resolve the propene absorption spectrum while the spectra of the other hydrocarbons could be resolved with 1 cm-1 resolution. High-resolution (0.1 cm-1), room-temperature measurements of neat hydrocarbons were made at low pressure (˜1 Torr, 133 Pa) and compared to measurements of hydrocarbon/N2 mixtures at atmospheric pressure to verify that no pressure broadening could be observed over this pressure range. The temperature was varied between 25 and 500 °C for atmospheric-pressure measurements of hydrocarbon/N2 mixtures (Xhydrocarbon˜0.06 1.5%) and it was found that the absorption cross section shows simple temperature-dependent behavior for a fixed wavelength over this temperature range. Comparisons with previous FTIR data over a limited temperature range and with high-resolution laser absorption data over a wide temperature range show good agreement.

  20. Instrumental studies on silicone oil adsorption to the surface of intraocular lenses

    NASA Astrophysics Data System (ADS)

    Kim, Chun Ho; Joo, Choun-Ki; Chun, Heung Jae; Yoo, Bok Ryul; Noh, Dong Il; Shim, Young Bock

    2012-12-01

    The purpose of this study was to examine the degree of adherence of silicone oil to various intraocular lenses (IOLs) through comparison of the physico-chemical properties of the oil and IOLs. Four kinds of IOLs comprising various biomaterials were examined: PMMA (720A™), PHEMA (IOGEL 1103™), Acrysof (MA60BM™), and silicone (SI30NB™). Each lens was immersed in silicone oil or carboxylated silicone (CS-PDMS) oil for 72 h. For determination of the changes in chemical and elemental compositions on the surfaces of IOLs caused by the contact with silicone oil, IOLs were washed and rinsed with n-pentane to remove as much of the adsorbed silicone oil as possible, then subjected to Fourier transform infrared spectroscopic (FTIR) and X-ray photoelectron spectroscopic (XPS) analyses. The results of FTIR studies strongly indicate that washing with n-pentane completely removed the adhered silicone oil on the surfaces of PHEMA and Acrysof IOLs, whereas the residual silicone oil was detected on the surfaces of PMMA and silicone IOLs. XPS studies showed that silicone oil coverage of PMMA lenses was 12%, even after washing with n-pentane. In the case of silicone IOLs, the relative O1s peak area of carboxyl group in the residual CS-PDMS oil was found to be ˜2.7%. Considering that 2.8% carboxyl group-substituted silicone oil was used in the present study, CS-PDMS oil covered the entire surface of the silicone IOLs.

  1. Real World of Industrial Chemistry: An Acid Can Be Basic.

    ERIC Educational Resources Information Center

    Fernelius, W. Conard, Ed.; And Others

    1979-01-01

    The uses of sulfuric acid in our technological society are given. The discussion includes sulfuric acid in the petroleum industry, construction industry, textile industry and in steel production. (SA)

  2. Integrating Chemistry Laboratory Instrumentation into the Industrial Internet: Building, Programming, and Experimenting with an Automatic Titrator

    ERIC Educational Resources Information Center

    Famularo, Nicole; Kholod, Yana; Kosenkov, Dmytro

    2016-01-01

    This project is designed to improve physical chemistry and instrumental analysis laboratory courses for undergraduate students by employing as teaching tools novel technologies in electronics and data integration using the industrial Internet. The project carried out by upper-division undergraduates is described. Students are exposed to a complete…

  3. Polymer Chemistry--An Elective in the New Leaving Chemistry Course: A Method of Teaching It

    ERIC Educational Resources Information Center

    Lister, G.

    1972-01-01

    A scheme is suggested for teaching concepts of polymer chemistry. Laboratory activities are suggested for the major topics. Interrelationships of different industrial uses of polymers are emphasized during the course. (PS)

  4. Convective heat transfer measurements in a vapour-liquid-liquid three-phase direct contact heat exchanger

    NASA Astrophysics Data System (ADS)

    Mahood, Hameed B.; Campbell, A. N.; Baqir, Ali Sh.; Sharif, A. O.; Thorpe, R. B.

    2018-06-01

    Energy usage is increasing around the world due to the continued development of technology, and population growth. Solar energy is a promising low-grade energy resource that can be harvested and utilised in different applications, such solar heater systems, which are used in both domestic and industrial settings. However, the implementation of an efficient energy conversion system or heat exchanger would enhance such low-grade energy processes. The direct contact heat exchanger could be the right choice due to its ability to efficiently transfer significant amounts of heat, simple design, and low cost. In this work, the heat transfer associated with the direct contact condensation of pentane vapour bubbles in a three-phase direct contact condenser is investigated experimentally. Such a condenser could be used in a cycle with a solar water heater and heat recovery systems. The experiments on the steady state operation of the three-phase direct contact condenser were carried out using a short Perspex tube of 70 cm in total height and an internal diameter of 4 cm. Only a height of 48 cm was active as the direct contact condenser. Pentane vapour, (the dispersed phase) with three different initial temperatures (40° C, 43.5° C and 47.5° C) was directly contacted with water (the continuous phase) at 19° C. The experimental results showed that the total heat transfer rate per unit volume along the direct contact condenser gradually decreased upon moving higher up the condenser. Additionally, the heat transfer rate increases with increasing mass flow rate ratio, but no significant effect on the heat transfer rate of varying the initial temperature of the dispersed phase was seen. Furthermore, both the outlet temperature of the continuous phase and the void fraction were positively correlated with the total heat transfer rate per unit volume, with no considerable effect of the initial temperature difference between the dispersed and continuous phases.

  5. Convective heat transfer measurements in a vapour-liquid-liquid three-phase direct contact heat exchanger

    NASA Astrophysics Data System (ADS)

    Mahood, Hameed B.; Campbell, A. N.; Baqir, Ali Sh.; Sharif, A. O.; Thorpe, R. B.

    2017-12-01

    Energy usage is increasing around the world due to the continued development of technology, and population growth. Solar energy is a promising low-grade energy resource that can be harvested and utilised in different applications, such solar heater systems, which are used in both domestic and industrial settings. However, the implementation of an efficient energy conversion system or heat exchanger would enhance such low-grade energy processes. The direct contact heat exchanger could be the right choice due to its ability to efficiently transfer significant amounts of heat, simple design, and low cost. In this work, the heat transfer associated with the direct contact condensation of pentane vapour bubbles in a three-phase direct contact condenser is investigated experimentally. Such a condenser could be used in a cycle with a solar water heater and heat recovery systems. The experiments on the steady state operation of the three-phase direct contact condenser were carried out using a short Perspex tube of 70 cm in total height and an internal diameter of 4 cm. Only a height of 48 cm was active as the direct contact condenser. Pentane vapour, (the dispersed phase) with three different initial temperatures (40° C, 43.5° C and 47.5° C) was directly contacted with water (the continuous phase) at 19° C. The experimental results showed that the total heat transfer rate per unit volume along the direct contact condenser gradually decreased upon moving higher up the condenser. Additionally, the heat transfer rate increases with increasing mass flow rate ratio, but no significant effect on the heat transfer rate of varying the initial temperature of the dispersed phase was seen. Furthermore, both the outlet temperature of the continuous phase and the void fraction were positively correlated with the total heat transfer rate per unit volume, with no considerable effect of the initial temperature difference between the dispersed and continuous phases.

  6. Final report on EURAMET.QM-S6/1195: Bilateral comparison of liquefied hydrocarbon mixtures in constant pressure (piston) cylinders

    NASA Astrophysics Data System (ADS)

    Brown, Andrew S.; Downey, Michael L.; Milton, Martin J. T.; van der Veen, Adriaan M. H.; Zalewska, Ewelina T.; Li, Jianrong

    2013-01-01

    Traceable liquid hydrocarbon mixtures are required in order to underpin measurements of the composition and other physical properties of LPG (liquefied petroleum gas) and LNG (liquefied natural gas), thus meeting the needs of an increasingly large European industrial market. The development of traceable liquid hydrocarbon standards by National Measurement Institutes (NMIs) was still at a relatively early stage at the time this comparison was proposed in 2011. NPL and VSL, who were the only NMIs active in this area, had developed methods for the preparation and analysis of such standards in constant pressure (piston) cylinders, but neither laboratory had Calibration and Measurement Capabilities (CMCs) for these mixtures. This report presents the results of EURAMET 1195, the first comparison of liquid hydrocarbon mixtures between NMIs, which assessed the preparation and analytical capabilities of NPL and VSL for these mixtures. The comparison operated between August 2011 and January 2012. Each laboratory prepared a liquid hydrocarbon standard with nominally the same composition and these standards were exchanged for analysis. The results of the comparison show a good agreement between the laboratories' results and the comparison reference values for the six components with amount fractions greater than 1.0 cmol/mol (propane, propene, iso-butene, n-butane, iso-butane and 1-butene). Measurement of the three components with lower amount fractions (1,3-butadiene, iso-pentane and n-pentane) proved more challenging. In all but one case, the differences from the comparison reference values for these three components were greater than the expanded measurement uncertainty. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by EURAMET, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  7. Immiscible Systems

    ERIC Educational Resources Information Center

    Eckelmann, Jens; Luning, Ulrich

    2013-01-01

    layers of liquids. The setup of both demonstrations is such that one homogeneous layer in a multiphasic mixture separates into two new layers upon shaking. The solvents used are methanol, toluene, petroleum ether or "n"-pentane, silicone oil, perfluoroheptanes,…

  8. Chemistry from Issues.

    ERIC Educational Resources Information Center

    Harding, Jan; Donaldson, Jim

    1986-01-01

    Describes the "Chemistry from Issues" project at Chelsea College. Provides the background information, rationale, and overall structure of a proposed course about the importance of chemistry to common culture. Outlines one module about the British steel industry that has been taught at King's College. (TW)

  9. Ask the experts: the challenges and benefits of flow chemistry to optimize drug development.

    PubMed

    Anderson, Neal; Gernaey, Krist V; Jamison, Timothy F; Kircher, Manfred; Wiles, Charlotte; Leadbeater, Nicholas E; Sandford, Graham; Richardson, Paul

    2012-09-01

    Against a backdrop of a struggling economic and regulatory climate, pharmaceutical companies have recently been forced to develop new ways to provide more efficient technology to meet the demands of a competitive drug industry. This issue, coupled with an increase in patent legislation and a rising generics market, makes these themes common issues in the growth of drug development. As a consequence, the importance of process chemistry and scale-up has never been more under the spotlight. Future Medicinal Chemistry wishes to share the thoughts and opinions of a variety of experts from this field, discussing issues concerning the use of flow chemistry to optimize drug development, the potential regulatory and environmental challenges faced with this, and whether the academic and industrial sectors could benefit from a more harmonized system relevant to process chemistry.

  10. Chemistry in California: How it Started and How it Grew

    ERIC Educational Resources Information Center

    Norberg, Arthur L.

    1976-01-01

    Gives a brief history of chemistry in California during the last 100 years, including the foundation of chemical industries, the development of chemistry departments in universities and their respective specialities, and the role of California laboratories in World War II. (MLH)

  11. An Industrially Developed Basic Chemistry Course.

    ERIC Educational Resources Information Center

    Collins, L. W.; Haws, L. D.

    1979-01-01

    Describes a practical, job-related, 3 1/2 month long, basic chemistry course developed by Monsanto Research Corporation to train laboratory technicians and service employees. The course, centered around 31 chemistry topics, is designed to supplement university courses and stresses application of concepts. (BT)

  12. Flash chemistry: flow chemistry that cannot be done in batch.

    PubMed

    Yoshida, Jun-ichi; Takahashi, Yusuke; Nagaki, Aiichiro

    2013-11-04

    Flash chemistry based on high-resolution reaction time control using flow microreactors enables chemical reactions that cannot be done in batch and serves as a powerful tool for laboratory synthesis of organic compounds and for production in chemical and pharmaceutical industries.

  13. Air Sparging Versus Gas Saturated Water Injection for Remediation of Volatile LNAPL in the Borden Aquifer

    NASA Astrophysics Data System (ADS)

    Barker, J.; Nelson, L.; Doughty, C.; Thomson, N.; Lambert, J.

    2009-05-01

    In the shallow, rather homogeneous, unconfined Borden sand aquifer, field trials of air sparging (Tomlinson et al., 2003) and pulsed air sparging (Lambert et al., 2009) have been conducted, the latter to remediate a residual gasoline source emplaced below the water table. As well, a supersaturated (with CO2) water injection (SWI) technology, using the inVentures inFusion system, has been trialed in two phases: 1. in the uncontaminated sand aquifer to evaluate the radius of influence, extent of lateral gas movement and gas saturation below the water table, and 2. in a sheet pile cell in the Borden aquifer to evaluate the recovery of volatile hydrocarbon components (pentane and hexane) of an LNAPL emplaced below the water table (Nelson et al., 2008). The SWI injects water supersaturated with CO2. The supersaturated injected water moves laterally away from the sparge point, releasing CO2 over a wider area than does gas sparging from a single well screen. This presentation compares these two techniques in terms of their potential for remediating volatile NAPL components occurring below the water table in a rather homogeneous sand aquifer. Air sparging created a significantly greater air saturation in the vicinity of the sparge well than did the CO2 system (60 percent versus 16 percent) in the uncontaminated Borden aquifer. However, SWI pushed water, still supersaturated with CO2, up to about 2.5 m from the injection well. This would seem to provide a considerable advantage over air sparging from a point, in that gas bubbles are generated at a much larger radius from the point of injection with SWI and so should involve additional gas pathways through a residual NAPL. Overall, air sparging created a greater area of influence, defined by measurable air saturation in the aquifer, but air sparging also injected about 12 times more gas than was injected in the SWI trials. The pulsed air sparging at Borden (Lambert et al.) removed about 20 percent (4.6 kg) of gasoline hydrocarbons, mainly pentane and hexane, from the residual gasoline via sparging. A similar mass was estimated to have been removed by aerobic biodegradation. The extent of volatile recovery needs to be better defined and so post-sparging coring and analysis of residual LNAPL is underway. Impressively, the second SWI trial recovered more than 60 percent of the pentane-hexane from the NAPL. In both field experiments there was potential for minor additional recovery if the system had been operated longer. Comparison of efficiency of the pulsed air sparging and SWI systems is difficult in that the initial LNAPL residuals have different chemistry, but similar distribution, different volumes of gas were used, and biodegradation accounted for a significant removal of hydrocarbons only in the air sparging system. The SWI trial recovered an impressive portion of the volatile LNAPL, while using considerably less gas than the air sparging system, but the SWI delivery system was both more complex and more expensive than the air sparging system. Additional trials are underway in more complex aquifers to further assess the performance of the SWI technology, including costs and practical limitations.

  14. A method for the solvent extraction of low-boiling-point plant volatiles.

    PubMed

    Xu, Ning; Gruber, Margaret; Westcott, Neil; Soroka, Julie; Parkin, Isobel; Hegedus, Dwayne

    2005-01-01

    A new method has been developed for the extraction of volatiles from plant materials and tested on seedling tissue and mature leaves of Arabidopsis thaliana, pine needles and commercial mixtures of plant volatiles. Volatiles were extracted with n-pentane and then subjected to quick distillation at a moderate temperature. Under these conditions, compounds such as pigments, waxes and non-volatile compounds remained undistilled, while short-chain volatile compounds were distilled into a receiving flask using a high-efficiency condenser. Removal of the n-pentane and concentration of the volatiles in the receiving flask was carried out using a Vigreux column condenser prior to GC-MS. The method is ideal for the rapid extraction of low-boiling-point volatiles from small amounts of plant material, such as is required when conducting metabolic profiling or defining biological properties of volatile components from large numbers of mutant lines.

  15. Pentan isomers compound flame front structure

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mansurov, Z.A.; Mironenko, A.W.; Bodikov, D.U.

    1995-08-13

    The fuels (hexane, pentane, diethyl ether) and conditions investigated in this study are relevant to engine knock in spark- ignition engines. A review is provided of the field of low temperature hydrocarbon oxidation. Studies were made of radical and stable intermediate distribution in the front of cool flames: Maximum concentrations of H atoms and peroxy radicals were observed in the luminous zone of the cool flame front. Peroxy radicals appear before the luminous zone at 430 K due to diffusion. H atoms were found in cool flames of butane and hexane. H atoms diffuses from the luminous zone to themore » side of the fresh mixture, and they penetrate into the fresh mixture to a small depth. Extension of action sphear of peroxy radicals in the fresh mixture is much greater than that of H atoms due to their small activity and high concentrations.« less

  16. Features of the propagation of laminar spherical flames initiated by a spark discharge in mixtures of methane, pentane, and hydrogen with air at atmospheric pressure

    NASA Astrophysics Data System (ADS)

    Rubtsov, N. M.; Seplyarskii, B. S.; Troshin, K. Ya.; Chernysh, V. I.; Tsvetkov, G. I.

    2011-10-01

    Using high-speed digital color cinematography, we studied the propagation of a laminar spherical flame in stoichiometric mixtures of hydrogen, methane, and pentane with air in the presence of additives at atmospheric pressure in constant-volume reactors, and derived quantitative data on the time of formation of a stable flame front. Cellular flames caused by gas-dynamic instability attributable to convective flows arising during the afterburning of gas were observed in hydrocarbon-air stoichiometric mixtures diluted with inert additives. It was found that the effect of additives of carbon dioxide and argon (>10%) and minor additives of CCl4 on the combustion of hydrocarbons, and of propylene on the combustion of hydrogen-rich mixtures, lead to periods of delay in the development of a laminar spherical flame; in addition, additives of propylene promote the combustion of hydrogen poor mixtures.

  17. Investigation of Y/SBA Composite Molecular Sieves Morphology Control and Catalytic Performance for n-Pentane Aromatization

    PubMed Central

    Shi, Chun-Wei; Wu, Wen-Yuan; Li, Shuai; Bian, Xue; Zhao, Shan-lin; Pei, Ming-Yuan

    2016-01-01

    Using Y molecular sieve as the core, Y/SBA-15 composite molecular sieves were prepared by different crystallization methods in the paper. The growth process and morphologies of the composite molecular sieves were controlled by adjusting the synthesis factors. The structures and acidity of two kinds of composite molecular sieves were characterized by X-ray diffraction (XRD), N2 adsorption/desorption, transmission electron microscopy (TEM), and NH3-TPD. The catalysis performances of the composite molecular sieves were investigated in the aromatization reaction of n-pentane. The results indicated that the desired core-shell composite molecular sieves were obtained when the crystallization conditions were 36 hours, 100 °C and secondary crystallization. The aromatization results showed that core-shell composite molecular sieves had better selectivity for producing high application value xylenes compared to mixed-crystal composite molecular sieves. PMID:27029526

  18. Liquid-state nuclear spin comagnetometers.

    PubMed

    Ledbetter, M P; Pustelny, S; Budker, D; Romalis, M V; Blanchard, J W; Pines, A

    2012-06-15

    We discuss nuclear spin comagnetometers based on ultralow-field nuclear magnetic resonance in mixtures of miscible solvents, each rich in a different nuclear spin. In one version thereof, Larmor precession of protons and 19F nuclei in a mixture of thermally polarized pentane and hexafluorobenzene is monitored via a sensitive alkali-vapor magnetometer. We realize transverse relaxation times in excess of 20 s and suppression of magnetic field fluctuations by a factor of 3400. We estimate it should be possible to achieve single-shot sensitivity of about 5×10(-9)  Hz, or about 5×10(-11)  Hz in ≈1 day of integration. In a second version, spin precession of protons and 129Xe nuclei in a mixture of pentane and hyperpolarized liquid xenon is monitored using superconducting quantum interference devices. Application to spin-gravity experiments, electric dipole moment experiments, and sensitive gyroscopes is discussed.

  19. Part 7: Environmental Chemistry, Revised.

    ERIC Educational Resources Information Center

    Douville, Judith A.

    2003-01-01

    Discusses resources on applied/interdisciplinary areas of chemistry available as books and electronic materials that mostly target graduate students, faculty, and chemists in the industry. (Author/YDS)

  20. Economic Aspects of the Chemical Industry

    NASA Astrophysics Data System (ADS)

    Koleske, Joseph V.

    Within the formal disciplines of science at traditional universities, through the years, chemistry has grown to have a unique status because of its close correspondence with an industry and with a branch of engineering—the chemical industry and chemical engineering. There is no biology industry, but aspects of biology have closely related disciplines such as fish raising and other aquaculture, animal cloning and other facets of agriculture, ethical drugs of pharmaceutical manufacture, genomics, water quality and conservation, and the like. Although there is no physics industry, there are power generation, electricity, computers, optics, magnetic media, and electronics that exist as industries. However, in the case of chemistry, there is a named industry. This unusual correspondence no doubt came about because in the chemical industry one makes things from raw materials—chemicals—and the science, manufacture, and use of chemicals grew up together during the past century or so.

  1. Pharmaceutical process chemistry: evolution of a contemporary data-rich laboratory environment.

    PubMed

    Caron, Stéphane; Thomson, Nicholas M

    2015-03-20

    Over the past 20 years, the industrial laboratory environment has gone through a major transformation in the industrial process chemistry setting. In order to discover and develop robust and efficient syntheses and processes for a pharmaceutical portfolio with growing synthetic complexity and increased regulatory expectations, the round-bottom flask and other conventional equipment familiar to a traditional organic chemistry laboratory are being replaced. The new process chemistry laboratory fosters multidisciplinary collaborations by providing a suite of tools capable of delivering deeper process understanding through mechanistic insights and detailed kinetics translating to greater predictability at scale. This transformation is essential to the field of organic synthesis in order to promote excellence in quality, safety, speed, and cost efficiency in synthesis.

  2. Computational Chemistry in the Pharmaceutical Industry: From Childhood to Adolescence.

    PubMed

    Hillisch, Alexander; Heinrich, Nikolaus; Wild, Hanno

    2015-12-01

    Computational chemistry within the pharmaceutical industry has grown into a field that proactively contributes to many aspects of drug design, including target selection and lead identification and optimization. While methodological advancements have been key to this development, organizational developments have been crucial to our success as well. In particular, the interaction between computational and medicinal chemistry and the integration of computational chemistry into the entire drug discovery process have been invaluable. Over the past ten years we have shaped and developed a highly efficient computational chemistry group for small-molecule drug discovery at Bayer HealthCare that has significantly impacted the clinical development pipeline. In this article we describe the setup and tasks of the computational group and discuss external collaborations. We explain what we have found to be the most valuable and productive methods and discuss future directions for computational chemistry method development. We share this information with the hope of igniting interesting discussions around this topic. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Discussion on the Development of Green Chemistry and Chemical Engineering

    NASA Astrophysics Data System (ADS)

    Zhang, Yunshen

    2017-11-01

    Chemical industry plays a vital role in the development process of national economy. However, in view of the special nature of the chemical industry, a large number of poisonous and harmful substances pose a great threat to the ecological environment and human health in the entire process of raw material acquisition, production, transportation, product manufacturing, and the final practical application. Therefore, it is a general trend to promote the development of chemistry and chemical engineering towards a greener environment. This article will focus on some basic problems occurred in the development process of green chemistry and chemical engineering.

  4. Ethylene by Naphta Cracking

    ERIC Educational Resources Information Center

    Wiseman, Peter

    1977-01-01

    Presents a discussion of the manufacture of ethylene by thermal cracking of hydrocarbon feedstocks that is useful for introducing the subject of industrial chemistry into a chemistry curriculum. (MLH)

  5. Knowledge Production at Industrial Research Institutes: Institutional Logics and Struggles for Relevance in the Swedish Institute for Surface Chemistry, 1980-2005

    ERIC Educational Resources Information Center

    Bruno, Karl; Larsen, Katarina; van Leeuwen, Thed N.

    2017-01-01

    This article examines dynamics of knowledge production and discourses of basic-applied science and relevance at the Swedish Institute for Surface Chemistry, a semi-public industrially oriented research institute, from 1980 to 2005. We employ a three-pronged method, consisting of (1) an analysis of how the institute articulated its research…

  6. Trace detection of perchlorate in industrial-grade emulsion explosive with portable surface-enhanced Raman spectroscopy.

    PubMed

    Nuntawong, N; Eiamchai, P; Limwichean, S; Wong-ek, B; Horprathum, M; Patthanasettakul, V; Leelapojanaporn, A; Nakngoenthong, S; Chindaudom, P

    2013-12-10

    Recent analyses by ion-exchange chromatography (IC) showed that, beside nitrate, the majority of the industrial-grade emulsion explosives, extensively used by most separatists in the southern Thailand insurgency, contained small traces of perchlorate anions. In demand for the faster, reliable, and simple detection methods, the portable detection of nitrate and perchlorate became the great interest for the forensic and field-investigators. This work proposed a unique method to detect the trace amount of perchlorate in seven industrial-grade emulsion explosives under the field tests. We utilized the combination of the portable Raman spectroscope, the developed surfaced-enhanced Raman substrates, and the sample preparation procedures. The portable Raman spectroscope with a laser diode of 785 nm for excitation and a thermoelectric-cooled CCD spectrometer for detection was commercially available. The SERS substrates, with uniformly distributed nanostructured silver nanorods, were fabricated by the DC magnetron sputtering system, based on the oblique-angle deposition technique. The sample preparation procedures were proposed based on (1) pentane extraction technique and (2) combustion technique, prior to being dissolved in the purified water. In comparison to the ion chromatography and the conventional Raman measurements, our proposed methods successfully demonstrated the highly sensitive detectability of the minimal trace amount of perchlorate from five of the explosives with minimal operating time. This work was therefore highly practical to the development for the forensic analyses of the post-blast explosive residues under the field-investigations. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  7. VOCs emission characteristics and priority control analysis based on VOCs emission inventories and ozone formation potentials in Zhoushan

    NASA Astrophysics Data System (ADS)

    Wang, Qiaoli; Li, Sujing; Dong, Minli; Li, Wei; Gao, Xiang; Ye, Rongmin; Zhang, Dongxiao

    2018-06-01

    Zhoushan is an island city with booming tourism and service industry, but also has many developed VOCs and/or NOX emission industries. It is necessary to carry out regional VOCs and O3 pollution control in Zhoushan as the only new area owns the provincial economic and social administration rights. Anthropogenic VOCs emission inventories were built based on emission factor method and main emission sources were identified according to the emission inventories. Then, localized VOCs source profiles were built based on in-site sampling and referring to other studies. Furthermore, ozone formation potentials (OFPs) profiles were built through VOCs source profiles and maximum incremental reactivity (MIR) theory. At last, the priority control analysis results showed that industrial processes, especially surface coating, are the key of VOCs and O3 control. Alkanes were the most emitted group, accounting for 58.67%, while aromatics contributed the most to ozone production accounting for 69.97% in total OFPs. n-butane, m/p-xylene, i-pentane, n-decane, toluene, propane, n-undecane, o-xylene, methyl cyclohexane and ethyl benzene were the top 10 VOC species that should be preferentially controlled for VOCs emission control. However, m/p-xylene, o-xylene, ethylene, n-butane, toluene, propene, 1,2,4-trimethyl benzene, 1,3,5-trimethyl benzene, ethyl benzene and 1,2,3-trimethyl benzene were the top 10 VOC species that required preferential control for O3 pollution control.

  8. [The effects of the success of the synthesis of Stovaïne in science and industry. Ernest Fourneau (1872-1949) and the transformation of the field of medicinal chemistry in France].

    PubMed

    Debue-Barazer, Christine

    2007-01-01

    The synthetic local anaesthetic Stovaine was commercialised in France in 1904. Its inventor, Ernest Fourneau, began his career as a pharmaceutical chemist in organic chemistry laboratories in Germany, where from 1899 to 1901 he discovered how basic research could benefit from the modern chemistry theories which had developed in Germany starting in the 1860s. Using the complex structure of cocaine, he invented an original molecule, with comparable activity, but less toxic. The knowledge and the know-how which he acquired in Germany nourished his reflection in the field of the chemistry of the relationships between structure and activity, and led him to the development of Stovaïne. Emile Roux, Director of the Pasteur Institute in Paris, was interested in his work and invited him to head the first French therapeutic chemistry laboratory, in which research on medicinal chemistry was organised scientifically. The industrial development of new medicines resulting from the Pasteur Institute's therapeutic chemistry laboratory was supported by the Etablissements Poulenc frères, France thus gaining international reputation in the domain of pharmaceutical chemistry.

  9. Rate Constants for the Reactions of Hydroxyl Radical with Several Alkanes, Cycloalkanes, and Dimethyl Ether

    NASA Technical Reports Server (NTRS)

    DeMore, W.; Bayes, K.

    1998-01-01

    Relative rate experiements were used to measure rate constants and temperature denpendencies of the reactions of OH with propane, n-butane, n-pentane, n-hexane, cyclopropane, cyclobutane, cyclopentane, and dimethyl ether.

  10. Chemistry-Climate Interactions in the GISS GCM. Part 1; Tropospheric Chemistry Model Description and Evaluation

    NASA Technical Reports Server (NTRS)

    Shindell, Drew T.; Grenfell, J. Lee; Rind, David; Price, Colin; Grewe, Volker; Hansen, James E. (Technical Monitor)

    2001-01-01

    A tropospheric chemistry module has been developed for use within the Goddard Institute for Space Studies (GISS) general circulation model (GCM) to study interactions between chemistry and climate change. The model uses a simplified chemistry scheme based on CO-NOx-CH4 chemistry, and also includes a parameterization for emissions of isoprene, the most important non-methane hydrocarbon. The model reproduces present day annual cycles and mean distributions of key trace gases fairly well, based on extensive comparisons with available observations. Examining the simulated change between present day and pre-industrial conditions, we find that the model has a similar response to that seen in other simulations. It shows a 45% increase in the global tropospheric ozone burden, within the 25% - 57% range seen in other studies. Annual average zonal mean ozone increases by more than 125% at Northern Hemisphere middle latitudes near the surface. Comparison of model runs that allow the calculated ozone to interact with the GCM's radiation and meteorology with those that do not shows only minor differences for ozone. The common usage of ozone fields that are not calculated interactively seems to be adequate to simulate both the present day and the pre-industrial ozone distributions. However, use of coupled chemistry does alter the change in tropospheric oxidation capacity, enlarging the overall decrease in OH concentrations from the pre-industrial to the present by about 10% (-5.3% global annual average in uncoupled mode, -5.9% in coupled mode). This indicates that there may be systematic biases in the simulation of the pre-industrial to present day decrease in the oxidation capacity of the troposphere (though a 10% difference is well within the total uncertainty). Global annual average radiative forcing from pre-industrial to present day ozone change is 0.32 W/sq m. The forcing seems to be increased by about 10% when the chemistry is coupled to the GCM. Forcing values greater than 0.8 W/sq m are seen over large areas of the United States, Southern Europe, North Africa, the Middle East, Central Asia, and the Arctic. Radiative forcing is greater than 1.5 W/sq m over parts of these areas during Northern summer Though there are local differences, the radiative forcing is overall in good agreement with the results of other modeling studies in both its magnitude and spatial distribution, demonstrating that the simplified chemistry is adequate for climate studies.

  11. Presidential Green Chemistry Challenge: 1996 Academic Award

    EPA Pesticide Factsheets

    Presidential Green Chemistry Challenge 1996 award winner, Professor Mark Holtzapple, developed methods to convert waste biomass (e.g., sewage sludge, agricultural wastes), into animal feed, industrial chemicals, or fuels.

  12. An Example of Learning about Plastics and Their Evaluation as a Contribution to Education for Sustainable Development in Secondary School Chemistry Teaching

    ERIC Educational Resources Information Center

    Burmeister, Mareike; Eilks, Ingo

    2012-01-01

    This paper describes the development and evaluation of a secondary school lesson plan for chemistry education on the topic Education for Sustainable Development (ESD). The lessons focus both on the chemistry of plastics and on learning about the societal evaluation of competing, chemistry-based industrial products. A specific teaching method was…

  13. 30 CFR 256.40 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... products means natural gas liquid products including the following: ethane, propane, butane, pentane... resulting from the removal of natural gas liquids and nonhydrocarbon gases. (3) Of liquefied petroleum products means the volume of natural gas liquids produced from reservoir gas and liquefied at surface...

  14. 30 CFR 556.40 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... products means natural gas liquid products including the following: ethane, propane, butane, pentane... resulting from the removal of natural gas liquids and nonhydrocarbon gases. (3) Of liquefied petroleum products mean the volume of natural gas liquids produced from reservoir gas and liquefied at surface...

  15. 30 CFR 556.40 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... products means natural gas liquid products including the following: ethane, propane, butane, pentane... resulting from the removal of natural gas liquids and nonhydrocarbon gases. (3) Of liquefied petroleum products mean the volume of natural gas liquids produced from reservoir gas and liquefied at surface...

  16. 30 CFR 556.40 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... products means natural gas liquid products including the following: ethane, propane, butane, pentane... resulting from the removal of natural gas liquids and nonhydrocarbon gases. (3) Of liquefied petroleum products mean the volume of natural gas liquids produced from reservoir gas and liquefied at surface...

  17. Presidential Green Chemistry Challenge: 1997 Designing Greener Chemicals Award

    EPA Pesticide Factsheets

    Presidential Green Chemistry Challenge 1997 award winner, Albright & Wilson Americas, discovered that tetrakis(hydroxymethyl)phosphonium sulfate, THPS, is an effective, safer biocide for use in industrial water systems.

  18. The Chemistry of a Mini

    ERIC Educational Resources Information Center

    Jones, C. E.

    1972-01-01

    Describes various parts of a mini car and their chemical composition. Useful information is included for science teachers to relate basic chemistry concepts and techniques with their application in automobile industry. (PS)

  19. Vertical Distribution of Non-Methane Hydrocarbons During Winter Ozone Production Events in the Uintah Basin

    NASA Astrophysics Data System (ADS)

    Stephens, C. R.; Helmig, D.; Evans, J.; Hueber, J.; Park, J.; Boylan, P.

    2013-12-01

    Emissions of non-methane hydrocarbons (NMHC) are primarily linked to anthropogenic fossil fuel activities, such as oil and natural gas extraction and distribution, and are important tropospheric ozone precursors. The Uintah Basin, Utah, is a region of heavy oil and natural gas development where high winter-time ozone production events have been observed during strong inversions when there is snow cover present. In the winters of 2012 and 2013, we conducted measurements of methane and NMHC during the Uintah Basin Winter Ozone Study. NMHC were monitored along a vertical gradient up to 150 m using a flux tower and tethered balloon. In 2013, measurements of NMHC were also conducted from within the snowpack. In 2012, no high ozone events were observed. In contrast, during the 2013 study, several periods of high ozone occurred concurrently with strong increases in ambient NMHC. Here, we present vertical profile measurements of C2-C5 alkanes, benzene and toluene comparing 2012 and 2013. Data from 2013 show strong vertical gradients with build-up of NMHC and ozone near the surface during inversion events, with wash out of both ozone and ozone precursors during low pressure front passage from the west. The NOAA/INSTAAR global flask network provides a useful comparison for expected regional background values of NMHC, and we find up to a 570-fold enhancement in Uintah, providing evidence for the importance of local emissions sources. Investigation of NMHC ratios reveals distinctly different values in the ambient air and within the snowpack, suggesting active radical chemistry occurring in the snow. Analysis of butane and pentane isomer ratios points towards the presence of chlorine radicals, indicating that the snow may serve as a reactive chlorine reservoir that may enhance ozone production chemistry.

  20. A glossary of corrosion-related terms used in science and industry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vukasovich, M.S.

    1995-12-31

    A Glossary of Corrosion-Related Terms Used in Science and Industry features definitions for over 4,000 specialized terms related to corrosion and corrosion prevention/control. Its coverage encompasses not only the fundamental terms commonly used in corrosion science, but also lesser-known, industry-specific jargon. The Glossary contains terms relevant to the study, effect, and control of corrosion that pertain to chemistry/electro-chemistry, metallurgy, plastics, paints/coatings, metal finishing, and the environment. Various synonyms, acronyms, and abbreviations are also included. A practical desk reference for students, scientists, engineers, technicians, and manufacturing and maintenance personnel.

  1. Thermal Chemistry of Cp*W(NO)(CH2CMe3)(H)(L) Complexes (L = Lewis Base).

    PubMed

    Fabulyak, Diana; Handford, Rex C; Holmes, Aaron S; Levesque, Taleah M; Wakeham, Russell J; Patrick, Brian O; Legzdins, Peter; Rosenfeld, Devon C

    2017-01-03

    The complexes trans-Cp*W(NO)(CH 2 CMe 3 )(H)(L) (Cp* = η 5 -C 5 Me 5 ) result from the treatment of Cp*W(NO)(CH 2 CMe 3 ) 2 in n-pentane with H 2 (∼1 atm) in the presence of a Lewis base, L. The designation of a particular geometrical isomer as cis or trans indicates the relative positions of the alkyl and hydrido ligands in the base of a four-legged piano-stool molecular structure. The thermal behavior of these complexes is markedly dependent on the nature of L. Some of them can be isolated at ambient temperatures [e.g., L = P(OMe) 3 , P(OPh) 3 , or P(OCH 2 ) 3 CMe]. Others undergo reductive elimination of CMe 4 via trans to cis isomerization to generate the 16e reactive intermediates Cp*W(NO)(L). These intermediates can intramolecularly activate a C-H bond of L to form 18e cis complexes that may convert to the thermodynamically more stable trans isomers [e.g., Cp*W(NO)(PPh 3 ) initially forms cis-Cp*W(NO)(H)(κ 2 -PPh 2 C 6 H 4 ) that upon being warmed in n-pentane at 80 °C isomerizes to trans-Cp*W(NO)(H)(κ 2 -PPh 2 C 6 H 4 )]. Alternatively, the Cp*W(NO)(L) intermediates can effect the intermolecular activation of a substrate R-H to form trans-Cp*W(NO)(R)(H)(L) complexes [e.g., L = P(OMe) 3 or P(OCH 2 ) 3 CMe; R-H = C 6 H 6 or Me 4 Si] probably via their cis isomers. These latter activations are also accompanied by the formation of some Cp*W(NO)(L) 2 disproportionation products. An added complication in the L = P(OMe) 3 system is that thermolysis of trans-Cp*W(NO)(CH 2 CMe 3 )(H)(P(OMe) 3 ) results in it undergoing an Arbuzov-like rearrangement and being converted mainly into [Cp*W(NO)(Me)(PO(OMe) 2 )] 2 , which exists as a mixture of two isomers. All new complexes have been characterized by conventional and spectroscopic methods, and the solid-state molecular structures of most of them have been established by single-crystal X-ray crystallographic analyses.

  2. Presidential Green Chemistry Challenge: 1999 Greener Reaction Conditions Award

    EPA Pesticide Factsheets

    Presidential Green Chemistry Challenge 1999 award winner, Nalco Chemical Co., developed homogeneous dispersion polymerization with water as the solvent to make polymers to treat water in industrial and municipal operations.

  3. Presidential Green Chemistry Challenge: 2012 Greener Reaction Conditions Award

    EPA Pesticide Factsheets

    Presidential Green Chemistry Challenge 2012 award winner, Cytec Industries, developed the MAX HT sodalite scale inhibitor for heat exchangers and pipes in the Bayer process, which converts bauxite into alumina.

  4. Presidential Green Chemistry Challenge: 2001 Designing Greener Chemicals Award

    EPA Pesticide Factsheets

    Presidential Green Chemistry Challenge 2001 award winner, PPG Industries, developed cationic electrodeposition coatings with yttrium that resist corrosion in automobiles. Yttrium is a safe replacement for lead in this use.

  5. Collection Development: Celebrating Chemistry, February 1, 2011

    ERIC Educational Resources Information Center

    Hamm, Susannah

    2011-01-01

    A hundred years after Marie Curie received her Nobel Prize in Chemistry, this arm of science is pointing the way to a more sustainable future. Growing movements like green chemistry, which strives to create alternative and new chemical reactions that produce no harmful waste products, and molecular engineering hold great potential for industry,…

  6. Predicting fire frequency with chemistry and climate

    Treesearch

    Richard P. Guyette; Michael C. Stambaugh; Daniel C. Dey; Rose-Marie Muzika

    2012-01-01

    A predictive equation for estimating fire frequency was developed from theories and data in physical chemistry, ecosystem ecology, and climatology. We refer to this equation as the Physical Chemistry Fire Frequency Model (PC2FM). The equation was calibrated and validated with North American fire data (170 sites) prior to widespread industrial influences (before ...

  7. The Chemistry behind Special Effects in Film and Television

    ERIC Educational Resources Information Center

    Short, Daniel B.; Badger, Paul D.

    2013-01-01

    The chemistry behind practical special effects in the film and television industry is discussed, along with examples of commonly used chemical demonstrations that simulate them in the laboratory. (Contains 3 figures.)

  8. Presidential Green Chemistry Challenge: 2002 Academic Award

    EPA Pesticide Factsheets

    Presidential Green Chemistry Challenge 2002 award winner, Professor Eric J. Beckman, developed fluorine-free detergents that help supercritical carbon dioxide (CO2) dissolve many chemicals, so it can be a solvent for industrial processes.

  9. Evaporation of binary mixtures in microgravity

    NASA Technical Reports Server (NTRS)

    Girgis, Morris; Matta, Nabil; Kolli, Kiran; Brown, Leon; Chubb, Kevin

    1995-01-01

    The motivation of this research is to obtain a better understanding of phase-change heat transfer within single and binary liquid meniscii, both in 1-g and 0-g environments. During phase 1 and part of phase 2, in a glass test cell with an inclined heated plate, 1-6 experiments on pentane with additions of decane up to 3% were conducted to determine the optimum concentration that will exhibit the maximum heat transfer and stability. During phase 2 emphasis was given to explore fundamental research issues and to ultimately develop a reliable capillary pumped loop (CPL) device for low gravity. In related experimental work, it was found that thermocapillary stresses near the contract line could result in a degraded wettability which ultimately could explain the observed failure of CPL devices in zero-gravity environment. Therefore, the current experimental effort investigates the effect of adding binary constituents in improving the thermocapillary characteristics near the contact line within the loop configuration. Achievements during second phase include: (1) Further enhancement of Central State University's Microgravity Laboratory by adding or improving upon capabilities of photography, video imaging, fluid visualization, and general experimental testing capabilities; (2) Experimental results for the inclined plate cell; (3) Modeling effort with a detailed scaling analysis; (4) Additional testing with a tube loop configuration to extend experimental work by Dickens, et al.; (5) Fabrication of a capillary loop to be tested using binary fluid (pentane/decane). The device that has been recently completed will be set up horizontally so that the effect of gravity on the performance is negligible. Testing will cover a wide range of parameters such as decane/pentane concentration, heat input value, heat input location (below or above meniscus), and loop temperature.

  10. Analysis of breath volatile organic compounds as a noninvasive tool to diagnose nonalcoholic fatty liver disease in children.

    PubMed

    Alkhouri, Naim; Cikach, Frank; Eng, Katharine; Moses, Jonathan; Patel, Nishaben; Yan, Chen; Hanouneh, Ibrahim; Grove, David; Lopez, Rocio; Dweik, Raed

    2014-01-01

    Nonalcoholic fatty liver disease (NAFLD) is one of the most common complications of childhood obesity. Our objective was to investigate the association of breath volatile organic compounds with the diagnosis of NAFLD in children. Patients were screened with an ultrasound of the abdomen to evaluate for NAFLD. Exhaled breath was collected and analyzed per protocol using selective ion flow tube mass spectrometry (SIFT-MS). Sixty patients were included in the study (37 with NAFLD and 23 with normal liver). All children were overweight or obese. The mean age was 14.1±2.8 years and 50% were female. A comparison of the SIFT-MS results of patients with NAFLD with those with normal liver on ultrasound revealed differences in concentration of more than 15 compounds. A panel of four volatile organic compounds can identify the presence of NAFLD with good accuracy (area under the receiver operating characteristic curve of 0.913 in the training set and 0.763 in the validation set). Breath isoprene, acetone, trimethylamine, acetaldehyde, and pentane were significantly higher in the NAFLD group compared with normal liver group (14.7 ppb vs. 8.9 for isoprene; 71.7 vs. 36.9 for acetone; 5.0 vs. 3.2 for trimethylamine; 35.1 vs. 26.0 for acetaldehyde; and 13.3 vs. 8.8 for pentane, P<0.05 for all). Exhaled breath analysis is a promising noninvasive method to detect fatty liver in children. Isoprene, acetone, trimethylamine, acetaldehyde, and pentane are novel biomarkers that may help to gain insight into pathophysiological processes leading to the development of NAFLD.

  11. A remarkable solvent effect on the nuclearity of neutral titanium(IV)-based helicate assemblies.

    PubMed

    Weekes, David Michael; Diebold, Carine; Mobian, Pierre; Huguenard, Clarisse; Allouche, Lionel; Henry, Marc

    2014-04-22

    The spontaneous self-assembly of a neutral circular trinuclear Ti(IV) -based helicate is described through the reaction of titanium(IV) isopropoxide with a rationally designed tetraphenolic ligand. The trimeric ring helicate was obtained after diffusion of n-pentane into a solution with dichloromethane. The circular helicate has been characterized by using single-crystal X-ray diffraction study, (13) C CP-MAS NMR and (1) H NMR DOSY solution spectroscopic, and positive electrospray ionization mass-spectrometric analysis. These analytical data were compared with those obtained from a previously reported double-stranded helicate that crystallizes in toluene. The trimeric ring was unstable in a pure solution with dichloromethane and transformed into the double-stranded helicate. Thermodynamic analysis by means of the PACHA software revealed that formation of the double-stranded helicates was characterized by ΔH(toluene)=-30 kJ mol(-1) and ΔS(toluene)=+357 J K(-1)  mol(-1) , whereas these values were ΔH(CH2 Cl2 )=-75 kJ mol(-1) and ΔS(CH2 Cl2 )=-37 J K(-1)  mol(-1) for the ring helicate. The transformation of the ring helicate into the double-stranded helicate was a strongly endothermic process characterized by ΔH(CH2 Cl2 )=+127 kJ mol(-1) and ΔH(n-pentane)=+644 kJ mol(-1) associated with a large positive entropy change ΔS=+1115 J K(-1) ⋅mol(-1) . Consequently, the instability of the ring helicate in pure dichloromethane was attributed to the rather high dielectric constant and dipole moment of dichloromethane relative to n-pentane. Suggestions for increasing the stability of the ring helicate are given. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Chemistry in Action: How to Plan a Visit to the Chemical Industry.

    ERIC Educational Resources Information Center

    Nae, Hemi; And Others

    1982-01-01

    Presents guidelines for field trips to chemical industries. Includes examples of objectives, administrative aspects (time off from school, contact persons, transportation, pre/post-trip discussions, and guides at the industrial facility). Includes an evaluation of trips taken to industrial plants in Israel. (JN)

  13. Cuticular hydrocarbons from the bed bug Cimex lectularius L.

    USDA-ARS?s Scientific Manuscript database

    Pentane extracts of male and female bed bugs were analyzed by gas chromatography and mass spectrometry in an effort to identify cuticular hydrocarbons. Seventeen hydrocarbons accounting for nearly 99% of the compounds eluting in the cuticular hydrocarbon region were identified. The sample contained ...

  14. 40 CFR 414.70 - Applicability; description of the bulk organic chemicals subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., Calcium Salt Maleic Anhydride Methacrylic Acid *Methacrylic Acid Esters Methane Methyl Ethyl Ketone Methyl Methacrylate Methyl Tert-Butyl Ether Methylisobutyl Ketone *n-Alkanes n-Butyl Alcohol n-Butylacetate n... Acid Nylon Salt Oxalic Acid *Oxo Aldehydes—Alcohols Pentaerythritol Pentane *Pentenes *Petroleum...

  15. 40 CFR 414.70 - Applicability; description of the bulk organic chemicals subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., Calcium Salt Maleic Anhydride Methacrylic Acid *Methacrylic Acid Esters Methane Methyl Ethyl Ketone Methyl Methacrylate Methyl Tert-Butyl Ether Methylisobutyl Ketone *n-Alkanes n-Butyl Alcohol n-Butylacetate n... Acid Nylon Salt Oxalic Acid *Oxo Aldehydes—Alcohols Pentaerythritol Pentane *Pentenes *Petroleum...

  16. 40 CFR 414.70 - Applicability; description of the bulk organic chemicals subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., Calcium Salt Maleic Anhydride Methacrylic Acid *Methacrylic Acid Esters Methane Methyl Ethyl Ketone Methyl Methacrylate Methyl Tert-Butyl Ether Methylisobutyl Ketone *n-Alkanes n-Butyl Alcohol n-Butylacetate n... Acid Nylon Salt Oxalic Acid *Oxo Aldehydes—Alcohols Pentaerythritol Pentane *Pentenes *Petroleum...

  17. 40 CFR 414.70 - Applicability; description of the bulk organic chemicals subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., Calcium Salt Maleic Anhydride Methacrylic Acid *Methacrylic Acid Esters Methane Methyl Ethyl Ketone Methyl Methacrylate Methyl Tert-Butyl Ether Methylisobutyl Ketone *n-Alkanes n-Butyl Alcohol n-Butylacetate n... Acid Nylon Salt Oxalic Acid *Oxo Aldehydes—Alcohols Pentaerythritol Pentane *Pentenes *Petroleum...

  18. Volatile organic compounds as markers of quality changes during the storage of wild rocket.

    PubMed

    Luca, Alexandru; Kjær, Anders; Edelenbos, Merete

    2017-10-01

    The quality of leafy green vegetables changes during storage. Leaves become yellow or disintegrate, and an off-odor may develop. In addition, small amounts of volatile organic compounds (VOCs) are released. In this study, the release of acetone, carbon disulfide, dimethyl sulfide, nitromethane, pentane, 3-methylfuran, 2-ethylfuran, and dimethyl disulfide from wild rocket with different initial qualities was monitored during 8d storage at 10°C and correlated to aerobic bacteria counts, yeast and mold counts, and degree of tissue disintegration. The release of VOCs, except for 3-methylfuran, was influenced by the initial quality of the leaves. The release of pentane and 2-ethylfuran was related to the degree of tissue disintegration, and the release of dimethyl sulfide and dimethyl disulfide was related to the total aerobic bacteria count. The results demonstrated that VOCs can be used as markers for monitoring the complex quality changes taking place in packaged fresh produce during storage. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Effect of oxidoreduction potential on aroma biosynthesis by lactic acid bacteria in nonfat yogurt.

    PubMed

    Martin, F; Cachon, R; Pernin, K; De Coninck, J; Gervais, P; Guichard, E; Cayot, N

    2011-02-01

    The aim of this study was to investigate the effect of oxidoreduction potential (Eh) on the biosynthesis of aroma compounds by lactic acid bacteria in non-fat yogurt. The study was done with yogurts fermented by Lactobacillus bulgaricus and Streptococcus thermophilus. The Eh was modified by the application of different gaseous conditions (air, nitrogen, and nitrogen/hydrogen). Acetaldehyde, dimethyl sulfide, diacetyl, and pentane-2,3-dione, as the major endogenous odorant compounds of yogurt, were chosen as tracers for the biosynthesis of aroma compounds by lactic acid bacteria. Oxidative conditions favored the production of acetaldehyde, dimethyl sulfide, and diketones (diacetyl and pentane-2,3-dione). The Eh of the medium influences aroma production in yogurt by modifying the metabolic pathways of Lb. bulgaricus and Strep. thermophilus. The use of Eh as a control parameter during yogurt production could permit the control of aroma formation. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  20. Maleate/vinyl ether UV-cured coatings: Effects of composition on curing and properties

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Noren, G.K.

    1996-10-01

    The effect of the composition of the maleate polyester and the vinyl ether terminated compound on their UV-curing and properties has been investigated. Linear unsaturated polyester resins based on maleic anhydride and 1,5-pentane diol were synthesized. The molecular weight of the unsaturated polyesters was varied by changing the ratio of maleic anhydride to 1,5-pentane diol and the double bond equivalent weight was varied by replacing maleic anhydride with succinic anhydride. Coating formulations containing these unsaturated polyesters, triethylene glycol divinyl ether and a free radical photoinitiator were crosslinked in the presence of UV light. The coatings were very brittle, exhibiting tensilemore » strengths in the range of 1.5-4.0 MPa and elongations of only 3-7%. Diethyl maleate and isobutyl vinyl ether were effective diluents for reducing viscosity but reduced the cure speed. A vinyl ether urethane oligomer was synthesized and enhanced the flexibility and toughness of the coatings when substituted for triethylene glycol divinyl ether.« less

  1. Hydrocarbons in the sediments of the Bermuda region lagoonal to abyssal depths

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sletter, T.D.; Butler, J.N.; Barbash, J.E.

    1980-01-01

    Gas chromatographic analyses of the pentane fraction derived from surface sediments collected from 20 stations (50 cores) around Bermuda from the subtidal zone to 40 m depth and one deep-water sediment sample from 1400 m depth showed that outside the protective boiler reef, the total aliphatic (pentane-extractable) hydrocarbon content was less than inside the reef (3-10 jg/g dry weight outside vs. 10-65 jg/g inside). Samples from the 1400 m depth showed < 1.0 jg/g aliphatic hydrocarbon content. The chromatograms from the shipping channels showed fresh petroleum source concentrations of 8-31 jg/g; harbors yielded chromatograms typical of chronic petroleum contamination, withmore » 30-110 jg/g concentrations. Several biogenic compounds (including C15 and C17 n-alkanes and most probably derived from marine algae) were observed, in addition to the petroleum-derived hydrocarbons. The criteria adopted for distinguishing biogenic and petroleum hydrocarbons are given.« less

  2. Tropospheric OH and Cl levels deduced from non-methane hydrocarbon measurements in a marine site

    NASA Astrophysics Data System (ADS)

    Arsene, C.; Bougiatioti, A.; Kanakidou, M.; Bonsang, B.; Mihalopoulos, N.

    2007-05-01

    In situ continuous hourly measurements of C2-C8 non-methane hydrocarbons (NMHCS) have been performed from March to October 2006 at two coastal locations on the island of Crete, in the Eastern Mediterranean. Well defined diurnal variations were observed for several short lived NMHCS (including ethene, propene, n-butane, n-pentane, n-hexane, 2-methyl-pentane). The daytime concentration of hydroxyl (OH) radicals estimated from these experimental data varied from 1.3×106 to ~4.0×106 radical cm-3, in good agreement with box-model simulations. In addition the relative variability of various hydrocarbon pairs (at least 7) was used to derive the tropospheric levels of Cl atoms. The Cl atom concentration has been estimated to range between 0.6×104 and 4.7×104 atom cm-3, in good agreement with gaseous hydrochloric acid (HCl) observations in the area. Such levels of Cl atoms can be of considerable importance for the oxidation capacity of the troposphere on a regional scale.

  3. Presidential Green Chemistry Challenge: 2003 Designing Greener Chemicals Award

    EPA Pesticide Factsheets

    Presidential Green Chemistry Challenge 2003 award winner, Shaw Industries, developed EcoWorx carpet tiles with a backing that uses less toxic materials. The carpet tile fiber and backing are readily separated for recycling.

  4. Exploring the Information Literacy Needs and Values of High School Chemistry Teachers

    ERIC Educational Resources Information Center

    Zane, Marci; Tucci, Valerie Karvey

    2016-01-01

    To meet the information literacy (IL) needs of chemistry students, The College of New Jersey's (TCNJ) Library and Chemistry Departments have created a three-year seminar with a strong IL component. The program focuses on IL skills necessary for success in industry and graduate or professional education, but may lack features specific to those…

  5. Bridging the Cognitive-Affective Gaps: Teaching Chemistry while Advancing Affective Objectives. The Singapore Curricular Experience

    ERIC Educational Resources Information Center

    Tan, Kok Siang; Goh, Ngoh Khang; Chia, Lian Sai

    2006-01-01

    Chemistry teachers face constraints when trying to integrate cognitive and affective objectives, and hence thoughtful lesson planning is required to achieve the goal. Chemistry teachers can educate students to be knowledgeable about chemical concepts, processes and the benefits of responsible practice by the chemical industry, while being aware,…

  6. ConfChem Conference on Select 2016 BCCE Presentations: Twentieth Year of the OLCC

    ERIC Educational Resources Information Center

    Belford, Robert E.

    2017-01-01

    The ACS CHED Committee on Computers in Chemical Education (CCCE) ran the first intercollegiate OnLine Chemistry Course (OLCC) on Environmental and Industrial Chemistry in 1996, and is offering the seventh OLCC on Cheminformatics and Public Compound Databases: An Introduction to Big Data in Chemistry in 2017. This Communication summarizes the past,…

  7. GREEN REACTION CHEMISTRIES PERFORMED IN THE SST REACTOR

    EPA Science Inventory


    The U. S. Environmental Protection Agency (USEPA) and Kreido Laboratories have established a Cooperative Research and Development Agreement (CRADA) collaboration, to develop and commercialize green and sustainable chemistries in the area of industrial chemical synthesis. Uti...

  8. ChemTechLinks: Alliances for Chemical Technician Education

    NASA Astrophysics Data System (ADS)

    Nameroff, Tamara

    2003-09-01

    ChemTechLinks (CTL) is a project of the American Chemical Society (ACS) Educational and International Activities Division and funded by the National Science Foundation to support and advance chemistry-based technician education. The project aims to help improve technician education programs, foster academic-industry alliances, provide professional development opportunities for faculty, and increase student recruitment into chemical technology. The CTL Web site serves as an information clearinghouse and link to other ACS resources and programs, including a Web-based, Voluntary Industry Standards (VIS) database, the Chemistry Technician Program Approval Service, the College Chemistry Consultants Service, summer workshops for high school teachers and two-year college faculty that emphasize a technology-oriented curriculum, scholarships for two-year college faculty to attend ACS Short Courses, a self-study instructional guide for faculty to use in preparing for classroom instruction, and information and free recruitment materials about career opportunities in chemistry technology.

  9. Teaching Chemistry Students How To Use Patent Databases and Glean Patent Information

    NASA Astrophysics Data System (ADS)

    MacMillan, Margy; Shaw, Lawton

    2008-07-01

    Patent literature is an important source of chemical information that is often neglected by chemical educators. This paper describes an effort to teach chemistry students how to use patent databases to search for information on applied chemical technology related to the manufacture of industrial and specialty chemicals. Students in a second-year-level organic chemistry class were shown how to search patent literature as part of a group research paper assignment that involved determining the feasibility of starting an industrial chemical operation to manufacture a given industrial chemical. Students who were assigned high value or specialty chemicals were most likely to cite patent literature in their final papers. Students who were assigned plastics or bulk commodity chemicals were less likely to cite patents. It is suggested that students made choices about the usefulness of patent literature and that patents were most useful when current patents existed and provided the patent owner a competitive advantage. For plastics or commodity chemicals, manufacturing technologies tend to be mature and are well described by more accessible information sources. Suggestions are made for effective introduction of patent literature instruction into upper-level chemistry courses.

  10. Incorporating a Soap Industry Case Study to Motivate and Engage Students in the Chemistry of Daily Life

    ERIC Educational Resources Information Center

    Chowdhury, Mohammad A.

    2013-01-01

    The global trend of the declining interest in chemistry education is a major concern. Over the last few decades, significant efforts and improvements have been made in various areas of chemistry education research to increase student motivation and engagement based on classroom and laboratory practices. However, little research has been conducted…

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

    ERIC Educational Resources Information Center

    Hill, Nicholas J.; Hoover, Jessica M.; Stahl, Shannon S.

    2013-01-01

    Modern undergraduate organic chemistry textbooks provide detailed discussion of stoichiometric Cr- and Mn-based reagents for the oxidation of alcohols, yet the use of such oxidants in instructional and research laboratories, as well as industrial chemistry, is increasingly avoided. This work describes a laboratory exercise that uses ambient air as…

  12. Pierre-Joseph Macquer: Chemistry in the French Enlightenment.

    PubMed

    Lehman, Christine

    2014-01-01

    Despite recent studies of chemistry courses and of academic research at the beginning of the eighteenth century, the perception of chemistry in the French Enlightenment has often been overshadowed by Lavoisier's works. This article proposes three specific case studies selected from Pierre Joseph Macquer's (1718-84) rich career to show the continuous evolution of chemistry throughout the century: medicinal chemistry through the application of the Comte de La Garaye's metallic salt solutions, the emergence of industrial chemistry through a few of Macquer's evaluations at the Bureau du Commerce, and finally communal academic research through the experiments on diamonds using Tschirnhaus's lens. These examples attempt to illustrate the innovative, creative, dynamic, multicultural, and multifaceted chemistry of the Enlightenment.

  13. Carbon source in the future chemical industries

    NASA Astrophysics Data System (ADS)

    Hofmann, Peter; Heinrich Krauch, Carl

    1982-11-01

    Rising crude oil prices favour the exploitation of hitherto unutilised energy carriers and the realisation of new technologies in all sectors where carbon is used. These changed economic constraints necessitate both savings in conventional petrochemistry and a change to oil-independent carbon sources in the chemical industry. While, in coal chemistry, the synthesis and process principles of petrochemistry — fragmentation of the raw material and subsequent buildup of molecular structures — can be maintained, the raw material structure largely remains unchanged in the chemistry of renewable raw materials. This lecture is to demonstrate the structural as well as the technological and energy criteria of the chemistry of alternative carbon sources, to forecast the chances of commercial realization and to discuss some promising fields of research and development.

  14. 40 CFR 98.406 - Data reporting requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Suppliers of Natural Gas and Natural Gas Liquids § 98.406 Data..., isobutane, and pentanes plus. (3) Annual volumes in Mscf of natural gas received for processing. (4) Annual... report for each LDC shall contain the following information. (1) Annual volume in Mscf of natural gas...

  15. 40 CFR 98.406 - Data reporting requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Suppliers of Natural Gas and Natural Gas Liquids § 98.406 Data..., isobutane, and pentanes plus. (3) Annual volumes in Mscf of natural gas received for processing. (4) Annual... Mscf of natural gas received by the LDC at its city gate stations for redelivery on the LDC's...

  16. 40 CFR 98.406 - Data reporting requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Suppliers of Natural Gas and Natural Gas Liquids § 98.406 Data..., isobutane, and pentanes plus. (3) Annual volumes in Mscf of natural gas received for processing. (4) Annual... Mscf of natural gas received by the LDC at its city gate stations for redelivery on the LDC's...

  17. 40 CFR 98.406 - Data reporting requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Suppliers of Natural Gas and Natural Gas Liquids § 98.406 Data..., isobutane, and pentanes plus. (3) Annual volumes in Mscf of natural gas received for processing. (4) Annual... shall contain the following information. (1) Annual volume in Mscf of natural gas received by the LDC at...

  18. 40 CFR 98.406 - Data reporting requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Suppliers of Natural Gas and Natural Gas Liquids § 98.406 Data..., isobutane, and pentanes plus. (3) Annual volumes in Mscf of natural gas received for processing. (4) Annual... Mscf of natural gas received by the LDC at its city gate stations for redelivery on the LDC's...

  19. Real World of Industrial Chemistry: Ethylene: The Organic Chemical Industry's Most Important Building Block.

    ERIC Educational Resources Information Center

    Fernelius, W. Conrad, Ed.; And Others

    1979-01-01

    The value of ethylene, as the organic chemical industry's most important building block, is discussed. The discussion focuses on the source of ethylene, its various forms and functions, and the ways in which the forms are made. (SA)

  20. Simultaneous assessment of phase chemistry, phase abundance and bulk chemistry with statistical electron probe micro-analyses: Application to cement clinkers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wilson, William; Krakowiak, Konrad J.; Ulm, Franz-Josef, E-mail: ulm@mit.edu

    2014-01-15

    According to recent developments in cement clinker engineering, the optimization of chemical substitutions in the main clinker phases offers a promising approach to improve both reactivity and grindability of clinkers. Thus, monitoring the chemistry of the phases may become part of the quality control at the cement plants, along with the usual measurements of the abundance of the mineralogical phases (quantitative X-ray diffraction) and the bulk chemistry (X-ray fluorescence). This paper presents a new method to assess these three complementary quantities with a single experiment. The method is based on electron microprobe spot analyses, performed over a grid located onmore » a representative surface of the sample and interpreted with advanced statistical tools. This paper describes the method and the experimental program performed on industrial clinkers to establish the accuracy in comparison to conventional methods. -- Highlights: •A new method of clinker characterization •Combination of electron probe technique with cluster analysis •Simultaneous assessment of phase abundance, composition and bulk chemistry •Experimental validation performed on industrial clinkers.« less

  1. GREEN REACTION CHEMISTRIES PERFORMED IN THE SPINNING TUBE-IN-TUBE (STT) REACTOR

    EPA Science Inventory

    The U. S. Environmental Protection Agency (USEPA) and Kreido Laboratories have established a Cooperative Research and Development Agreement (CRADA) collaboration, to develop and commercialize green and sustainable chemistries in the area of industrial chemical synthesis. Utilizi...

  2. Presidential Green Chemistry Challenge: 2015 Specific Environmental Benefit: Climate Change Award

    EPA Pesticide Factsheets

    Presidential Green Chemistry Challenge 2015 award winner, Algenol, blue-green algae to produce ethanol and other fuels, uses CO2 from air or industrial emitters, reduces the carbon footprint, costs and water usage, no reliance on food crops

  3. The Kinetics and Thermodynamics of the Phenol from Cumene Process: A Physical Chemistry Experiment.

    ERIC Educational Resources Information Center

    Chen, Edward C. M.; Sjoberg, Stephen L.

    1980-01-01

    Presents a physical chemistry experiment demonstrating the differences between thermodynamics and kinetics. The experiment used the formation of phenol and acetone from cumene hydroperoxide, also providing an example of an industrially significant process. (CS)

  4. Starch: chemistry, microstructure, processing and enzymatic degradation

    USDA-ARS?s Scientific Manuscript database

    Starch is recognized as one of the most abundant and important commodities containing value added attributes for a vast number of industrial applications. Its chemistry, structure, property and susceptibility to various chemical, physical and enzymatic modifications offer a high technological value ...

  5. Drug discovery chemistry: a primer for the non-specialist.

    PubMed

    Jordan, Allan M; Roughley, Stephen D

    2009-08-01

    Like all scientific disciplines, drug discovery chemistry is rife with terminology and methodology that can seem intractable to those outside the sphere of synthetic chemistry. Derived from a successful in-house workshop, this Foundation Review aims to demystify some of this inherent terminology, providing the non-specialist with a general insight into the nomenclature, terminology and workflow of medicinal chemists within the pharmaceutical industry.

  6. Dirt Alert--The Chemistry of Cleaning. Hands-on Science Activities for Grades 4-12. Science in Our World, Volume Three.

    ERIC Educational Resources Information Center

    Sarquis, Mickey, Ed.

    This monograph focuses on the chemistry of cleaning and enables teachers to introduce their students to the concepts and processes of industrial chemistry and relate these concepts to the consumer products students encounter daily. This teacher resource module is organized into sections that provide information on how to use the resource module,…

  7. Science Fare--Chemistry at the Table. Hands-on Science Activities for Grades 4-12. Science in Our World, Volume One.

    ERIC Educational Resources Information Center

    Sarquis, Mickey, Ed.

    This monograph focuses on chemistry at the table and enables teachers to introduce their students to the concepts and processes of industrial chemistry and relate these concepts to the consumer products students encounter daily. This teacher resource module is organized into sections that provide information on how to use the resource module, how…

  8. Strong Medicine--Chemistry at the Pharmacy. Hands-on Science Activities for Grades 7-12. Science in Our World, Volume Two.

    ERIC Educational Resources Information Center

    Sarquis, Mickey, Ed.

    This monograph focuses on chemistry at the pharmacy and enables teachers to introduce their students to the concepts and processes of industrial chemistry and relate these concepts to the consumer products students encounter daily. This teacher resource module is organized into sections that provide information on how to use the resource module,…

  9. Chain Gang--The Chemistry of Polymers. Hands-on Science Activities for Grades 4-12. Science in Our World, Volume Five.

    ERIC Educational Resources Information Center

    Sarquis, Mickey, Ed.

    This monograph focuses on the chemistry of polymers and enables teachers to introduce their students to the concepts and processes of industrial chemistry and relate these concepts to the consumer products students encounter daily. This teacher resource module is organized into sections that provide information on how to use the resource module,…

  10. Fat Chance--The Chemistry of Lipids. Hands-on Science Activities for Grades 4-12. Science in Our World, Volume Four.

    ERIC Educational Resources Information Center

    Sarquis, Mickey, Ed.

    This monograph focuses on the chemistry of lipids and enables teachers to introduce their students to the concepts and processes of industrial chemistry and relate these concepts to the consumer products students encounter daily. This teacher resource module is organized into sections that provide information on how to use the resource module, how…

  11. Thermocapillary flow contribution to dropwise condensation heat transfer

    NASA Astrophysics Data System (ADS)

    Phadnis, Akshay; Rykaczewski, Konrad

    2017-11-01

    With recent developments of durable hydrophobic materials potentially enabling industrial applications of dropwise condensation, accurate modeling of heat transfer during this phase change process is becoming increasingly important. Classical steady state models of dropwise condensation are based on the integration of heat transfer through individual droplets over the entire drop size distribution. These models consider only the conduction heat transfer inside the droplets. However, simple scaling arguments suggest that thermocapillary flows might exist in such droplets. In this work, we used Finite Element heat transfer model to quantify the effect of Marangoni flow on dropwise condensation heat transfer of liquids with a wide range of surface tensions ranging from water to pentane. We confirmed that the Marangoni flow is present for a wide range of droplet sizes, but only has quantifiable effects on heat transfer in drops larger than 10 µm. By integrating the single drop heat transfer simulation results with drop size distribution for the cases considered, we demonstrated that Marangoni flow contributes a 10-30% increase in the overall heat transfer coefficient over conduction only model.

  12. Intelligent Chemistry Management System (ICMS)--A new approach to steam generator chemistry control

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barto, R.J.; Farrell, D.M.; Noto, F.A.

    1986-04-01

    The Intelligent Chemistry Management System (ICMS) is a new tool which assists in steam generator chemistry control. Utilizing diagnostic capabilities, the ICMS will provide utility and industrial boiler operators, system chemists, and plant engineers with a tool for monitoring, diagnosing, and controlling steam generator system chemistry. By reducing the number of forced outages through early identification of potentially detrimental conditions, suggestion of possible causes, and execution of corrective actions, improvements in unit availability and reliability will result. The system monitors water and steam quality at a number of critical locations in the plant.

  13. Doctorate Program Trains Industrial Chemists.

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1982

    1982-01-01

    The University of Texas (Dallas) has initiated a new Ph.D. program specifically to train chemists for doctoral level work in industry (Doctor of Chemistry). Participants will complete three research practica (at an industrial site and in two laboratory settings) instead of the traditional dissertation, emphasizing breadth and flexibility in…

  14. Platinum adlayered ruthenium nanoparticles, method for preparing, and uses thereof

    DOEpatents

    Tong, YuYe; Du, Bingchen

    2015-08-11

    A superior, industrially scalable one-pot ethylene glycol-based wet chemistry method to prepare platinum-adlayered ruthenium nanoparticles has been developed that offers an exquisite control of the platinum packing density of the adlayers and effectively prevents sintering of the nanoparticles during the deposition process. The wet chemistry based method for the controlled deposition of submonolayer platinum is advantageous in terms of processing and maximizing the use of platinum and can, in principle, be scaled up straightforwardly to an industrial level. The reactivity of the Pt(31)-Ru sample was about 150% higher than that of the industrial benchmark PtRu (1:1) alloy sample but with 3.5 times less platinum loading. Using the Pt(31)-Ru nanoparticles would lower the electrode material cost compared to using the industrial benchmark alloy nanoparticles for direct methanol fuel cell applications.

  15. PROCESS INTENSIFIED GREEN REACTION CHEMISTRIES PERFORMED IN THE SPINNING TUBE-IN-TUBE (STT®) REACTOR

    EPA Science Inventory

    The U. S. Environmental Protection Agency (USEPA) and Kreido Laboratories have established a Cooperative Research and Development Agreement (CRADA) collaboration, to develop and commercialize green and sustainable chemistries in the area of industrial chemical synthesis. Utilizi...

  16. Harold Seifried, PhD | Division of Cancer Prevention

    Cancer.gov

    Dr. Harold Seifried is a member of the American Chemical Society Biological Chemistry Division; American College of Toxicology Industrial Toxicology Subcommittee; American Industrial Hygiene Association; Society of Toxicology; International Society for the Study of Xenobiotics; Diplomate of the American Board of Toxicology since 1980; American Board of Industrial Hygiene,

  17. Sustainable Chemistry, the Spinning Tube-in-Tube (STT(R)) Reactor and GREENSCOPE: Innovation and Industrial Partnerships

    EPA Science Inventory

    The chemical industry faces environmental, social and health challenges that are common across all economic sectors. From worker exposure to toxic substances, to product design and use, to the cost and handling of waste disposal, the industry must overcome numerous complex hurdle...

  18. Industrial medicinal chemistry insights: neuroscience hit generation at Janssen.

    PubMed

    Tresadern, Gary; Rombouts, Frederik J R; Oehlrich, Daniel; Macdonald, Gregor; Trabanco, Andres A

    2017-10-01

    The role of medicinal chemistry has changed over the past 10 years. Chemistry had become one step in a process; funneling the output of high-throughput screening (HTS) on to the next stage. The goal to identify the ideal clinical compound remains, but the means to achieve this have changed. Modern medicinal chemistry is responsible for integrating innovation throughout early drug discovery, including new screening paradigms, computational approaches, novel synthetic chemistry, gene-family screening, investigating routes of delivery, and so on. In this Foundation Review, we show how a successful medicinal chemistry team has a broad impact and requires multidisciplinary expertise in these areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Chemistry Perfumes Your Daily Life

    ERIC Educational Resources Information Center

    Fortineau, Anne-Dominique

    2004-01-01

    A synopsis on the history of perfumery is presented, along with the various processes accessible for obtaining natural perfume constituents, and creation of synthetic chemicals. The important contribution of organic chemists in the invention of perfumes, aspects of fragrance chemistry, and general information on the perfume industry are…

  20. 40 CFR 60.631 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... feedstock gas entering the natural gas processing plant. In light liquid service means that the piece of equipment contains a liquid that meets the conditions specified in § 60.485(e) or § 60.633(h)(2). In wet gas... the process. Natural gas liquids means the hydrocarbons, such as ethane, propane, butane, and pentane...

  1. 40 CFR 60.631 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... feedstock gas entering the natural gas processing plant. In light liquid service means that the piece of equipment contains a liquid that meets the conditions specified in § 60.485(e) or § 60.633(h)(2). In wet gas... the process. Natural gas liquids means the hydrocarbons, such as ethane, propane, butane, and pentane...

  2. 40 CFR 60.631 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... feedstock gas entering the natural gas processing plant. In light liquid service means that the piece of equipment contains a liquid that meets the conditions specified in § 60.485(e) or § 60.633(h)(2). In wet gas... the process. Natural gas liquids means the hydrocarbons, such as ethane, propane, butane, and pentane...

  3. Role of alcohol dehydrogenase activity and the acetaldehyde in ethanol- induced ethane and pentane production by isolated perfused rat liver.

    PubMed Central

    Müller, A; Sies, H

    1982-01-01

    The volatile hydrocarbons ethane and n-pentane are produced at increased rates by isolated perfused rat liver during the metabolism of acutely ethanol. The effect is half-maximal at 0.5 mM-ethanol, and its is not observed when inhibitors of alcohol dehydrogenase such as 4-methyl- or 4-propyl-pyrazole are also present. Propanol, another substrate for the dehydrogenase, is also active. Increased alkane production can be initiated by adding acetaldehyde in the presence of 4-methyl- or 4-propyl-pyrazole. An antioxidant, cyanidanol, suppresses the ethanol-induced alkane production. The data obtained with the isolated organ demonstrate that products known to arise from the peroxidation of polyunsaturated fatty acids are formed in the presence of ethanol and that the activity of alcohol dehydrogenase is required for the generation of the active radical species. The mere presence of ethanol, e.g. at binding sites of special form(s) of cytochrome P-450, it not sufficient to elicit an increased production of volatile hydrocarbons by rat liver. PMID:6751324

  4. On sub-T(g) dewetting of nanoconfined liquids and autophobic dewetting of crystallites.

    PubMed

    Souda, Ryutaro

    2012-03-28

    The glass transition temperature (T(g)) of thin films is reduced by nanoconfinement, but it is also influenced by the free surface and substrate interface. To gain more insights into their contributions, dewetting behaviors of n-pentane, 3-methylpentane, and toluene films are investigated on various substrates as functions of temperature and film thickness. It is found that monolayers of these molecules exhibit sub-T(g) dewetting on a perfluoro-alkyl modified Ni substrate, which is attributable to the evolution of a 2D liquid. The onset temperature of dewetting increases with film thickness because fluidity evolves via cooperative motion of many molecules; sub-T(g) dewetting is observed for films thinner than 5 monolayers. In contrast, monolayers wet substrates of graphite, silicon, and amorphous solid water until crystallization occurs. The crystallites exhibit autophobic dewetting on the substrate covered with a wetting monolayer. The presence of premelting layers is inferred from the fact that n-pentane crystallites disappear on amorphous solid water via intermixing. Thus, the properties of quasiliquid formed on the crystallite surface differ significantly from those of the 2D liquid formed before crystallization.

  5. Determination of the boiling-point distribution by simulated distillation from n-pentane through n-tetratetracontane in 70 to 80 seconds.

    PubMed

    Lubkowitz, Joaquin A; Meneghini, Roberto I

    2002-01-01

    This work presents the carrying out of boiling-point distributions by simulated distillation with direct-column heating rather than oven-column heating. Column-heating rates of 300 degrees C/min are obtained yielding retention times of 73 s for n-tetratetracontane. The calibration curves of the retention time versus the boiling point, in the range of n-pentane to n-tetratetracontane, are identical to those obtained by slower oven-heating rates. The boiling-point distribution of the reference gas oil is compared with that obtained with column oven heating at rates of 15 to 40 degrees C/min. The results show boiling-point distribution values nearly the same (1-2 degrees F) as those obtained with oven column heating from the initial boiling point to 80% distilled off. Slightly higher differences are obtained (3-4 degrees F) for the 80% distillation to final boiling-point interval. Nonetheless, allowed consensus differences are never exceeded. Precision of the boiling-point distributions (expressed as standard deviations) are 0.1-0.3% for the data obtained in the direct column-heating mode.

  6. Boiling of an emulsion in a yield stress fluid.

    PubMed

    Guéna, Geoffroy; Wang, Ji; d'Espinose, Jean-Baptiste; Lequeux, François; Talini, Laurence

    2010-11-01

    We report the boiling behavior of pentane emulsified in a yield stress fluid, a colloidal clay (Laponite) suspension. We have observed that a superheated state is easily reached: the emulsion, heated more than 50 °C above the alkane boiling point, does not boil. Superheating is made possible by the suppression of heterogeneous nucleation in pentane, resulting from the emulsification process, a phenomenon evidenced decades ago in studies of the superheating of two phase fluids. We have furthermore studied the growth of isolated bubbles nucleated in the emulsion. The rate of increase of the bubble radius with time depends on both the temperature and emulsion volume fraction but, rather unexpectedly, does not depend on the fluid rheology. We show that the bubbles grow by diffusion of the alkane through the aqueous phase between liquid droplets and bubbles, analogously to an Ostwald ripening process. The peculiarity of the process reported here is that a layer depleted in oil droplets forms around the bubble, layer to which the alkane concentration gradient is confined. We successfully describe our experimental results with a simple transfer model.

  7. Volatiles from a rare Acer spp. honey sample from Croatia.

    PubMed

    Jerković, Igor; Marijanović, Zvonimir; Malenica-Staver, Mladenka; Lusić, Drazen

    2010-06-24

    A rare sample of maple (Acer spp.) honey from Croatia was analysed. Ultrasonic solvent extraction (USE) using: 1) pentane, 2) diethyl ether, 3) a mixture of pentane and diethyl ether (1:2 v/v) and 4) dichloromethane as solvents was applied. All the extracts were analysed by GC and GC/MS. The most representative extracts were 3) and 4). Syringaldehyde was the most striking compound, being dominant in the extracts 2), 3) and 4) with percentages 34.5%, 33.1% and 35.9%, respectively. In comparison to USE results of other single Croatian tree honey samples (Robinia pseudoacacia L. nectar honey, Salix spp. nectar and honeydew honeys, Quercus frainetto Ten. honeydew as well as Abies alba Mill. and Picea abies L. honeydew) and literature data the presence of syringaldehyde, previously identified in maple sap and syrup, can be pointed out as a distinct characteristic of the Acer spp. honey sample. Headspace solid-phase microextraction (HS-SPME) combined with GC and GC/MS identified benzaldehyde (16.5%), trans-linalool oxide (20.5%) and 2-phenylethanol (14.9%) as the major compounds that are common in different honey headspace compositions.

  8. Spectroscopic studies and antibacterial activities of some new 16-membered octaazamacrocyclic complexes derived from thiocarbohydrazide and pentane-2,4-dione

    NASA Astrophysics Data System (ADS)

    Singh, D. P.; Kumar, Krishan; Chopra, Rimpi Mehani ne'e.

    2011-02-01

    A series of macrocyclic complexes of the type [M(C 12H 20N 8S 2)X 2]; where M = Co(II), Ni(II), Cu(II), Zn(II); X = Cl -, NO 3-, CH 3COO - has been synthesized by template condensation of thiocarbohydrazide and pentane-2,4-dione in the presence of divalent metal salts in methanolic medium. The complexes have been characterized with the help of elemental analyses, conductance measurements, magnetic measurements, electronic, NMR, IR, EPR and MS spectral studies. The low value of molar conductance indicates them to be non-electrolytes. On the basis of various studies a distorted octahedral geometry may be proposed for all of these complexes. These metal complexes were also tested for their in vitro antibacterial activities against some Gram-positive bacterial strains, i.e., Bacillus subtilis, Bacillus stearothermophilus and two Gram-negative bacterial strains, i.e., Escherichia coli, Pseudomonas putida. The results obtained were compared with standard antibiotics, Chloramphenicol and Streptomycin and found that some of the synthesized complexes show good antibacterial activities as compared to the standard antibiotics.

  9. Aging of SRC liquids

    NASA Astrophysics Data System (ADS)

    Hara, T.; Jones, L.; Tewari, K. C.; Li, N. C.

    1981-02-01

    The viscosity of SRC-LL liquid increases when subjected to accelerated aging by bubbling oxygen in the presence of copper strip at 62°C. Precipitates are formed and can be separated from the aged liquid by Soxhlet extraction with pentane. A 30-70 blend of SRC-I with SRC-LL was subjected to oxygen aging in the absence of copper, and the viscosity increased dramatically after 6 days at 62°. The content of preasphaltene and its molecular size increase with time of aging, accompanied by decrease of asphaltene and pentane-soluble contents. For the preasphaltene fraction on aging, gel permeation chromatography shows formation of larger particles. ESR experiments show that with oxygen aging, spin concentration in the preasphaltene fraction decreases. Perhaps some semiquinone, together with di- and tri-substituted phenoxy radicals, generated by oxygen aging of the coal liquid, interact with the free radicals already present in coal to yield larger particles and reduce free radical concentration. We are currently using the very high-field (600-MHz) NMR spectrometer at Mellon Institute to determine changes in structural parameters before and after aging of SRC-II and its chromatographically separated fractions.

  10. First Report on Rare Unifloral Honey of Endemic Moltkia petraea (Tratt.) Griseb. from Croatia: Detailed Chemical Screening and Antioxidant Capacity.

    PubMed

    Jerković, Igor; Marijanović, Zvonimir; Zekić, Marina; Tuberoso, Carlo I G

    2017-03-01

    Rare Moltkia petraea (Tratt.) Griseb. honey from Croatia was first time characterised. The spectrophotometric assays on CIE L*a*b*C ab *h ab ° colour coordinates, total phenol content and antioxidant capacity (FRAP, CUPRAC, DPPH • and ABTS •+ assays) determined higher honey values generally close to dark honeys ranges. Headspace solid-phase microextraction (HS-SPME) on two fibres after GC-FID and GC/MS revealed the major compounds 2-phenylacetaldehyde (12.8%; 15.6%), benzaldehyde (11.1%; 10.0%), octane (9.3%; 7.6%), nonane, propan-2-one, pentan-2-one, pentanal and nonanal (4.9%; 14.5%). Ultrasonic solvent extraction (USE) mainly isolated non-specific higher molecular compounds characteristic of the comb environment. Targeted HLPC-DAD analysis of the honey determined higher concentration of phenylalanine (212.08 mg/kg) and lumichrome (16.25 mg/kg) along with tyrosine and kojic acid. The headspace composition (chemical fingerprint) and high concentration of lumichrome can be considered particular for M. petraea honey. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

  11. Hydronium ion motion in nanometer 3-methyl-pentane films

    NASA Astrophysics Data System (ADS)

    Bell, Richard C.; Wu, Kai; Iedema, Martin J.; Cowin, James P.

    2007-07-01

    An ion soft-landing approach was applied to study the motion of hydronium (D3O+) and cesium (Cs+) ions from 84to104K in glassy 3-methyl-pentane (3MP) films vapor deposited on Pt(111). Both ions were found to have very similar mobilities in 3MP. The span of ion mobilities probed is from ˜10-18to˜10-13m2V-1s-1. Ion transport in these films was studied as a function of film thickness and electric field strength. The drift velocity was found to be linear with applied field below about 2×108V/m and deviated from linearity above this. To a large extent, D3O+ and Cs+ motion in 3MP was well predicted by a simple continuum-based ion mobility model in films from 25 to 20 000 ML thick (including pronounced perturbations 7 ML from both the vacuum and Pt interfaces). The mobility varied with temperature more slowly than predicted by Stokes' law, which may be due to extended inhomogeneous structures in the 3MP near its glass transition at 77K.

  12. Rate constant for OH with selected large alkanes : shock-tube measurements and an improved group scheme.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sivaramakrishnan, R.; Michael, J. V.; Chemical Sciences and Engineering Division

    High-temperature rate constant experiments on OH with the five large (C{sub 5}-C{sub 8}) saturated hydrocarbons n-heptane, 2,2,3,3-tetramethylbutane (2,2,3,3-TMB), n-pentane, n-hexane, and 2,3-dimethylbutane (2,3-DMB) were performed with the reflected-shock-tube technique using multipass absorption spectrometric detection of OH radicals at 308 nm. Single-point determinations at {approx}1200 K on n-heptane, 2,2,3,3-TMB, n-hexane, and 2,3-DMB were previously reported by Cohen and co-workers; however, the present work substantially extends the database to both lower and higher temperature. The present experiments span a wide temperature range, 789-1308 K, and represent the first direct measurements of rate constants at T > 800 K for n-pentane. The presentmore » work utilized 48 optical passes corresponding to a total path length of {approx}4.2 m. As a result of this increased path length, the high OH concentration detection sensitivity permitted pseudo-first-order analyses for unambiguously measuring rate constants.« less

  13. Selective pressurized liquid extraction of polychlorinated biphenyls from fat-containing food and feed samples influence of cell dimensions, solvent type, temperature and flush volume.

    PubMed

    Sporring, Sune; Björklund, Erland

    2004-06-25

    Sulphuric acid impregnated silica was used for the lipid free extraction of polychlorinated biphenyls from fat containing food and feed matrices using pressurized liquid extraction on a Dionex ASE300, with 34 mL cells. Data were compared to a previous publication where extractions had been performed on a Dionex ASE200, with 33 mL cells. Four different fat/fat retainer ratios (FFRs) were tested (0.100, 0.075, 0.050 and 0.025) at 50 and 100 degrees C using n-pentane, n-hexane or n-heptane as extraction solvent. The best results were obtained with a FFR of 0.025 when applying a temperature of 100 degrees C. Both n-pentane and n-heptane were capable of replacing n-hexane as extraction solvent. A flush volume of 60% was sufficient as suggested in US Environmental Protection Agency Method 3545. The applicability of the method was demonstrated for naturally contaminated fish meal as well as various spiked and certified materials.

  14. Prediction of warmed-over flavour development in cooked chicken by colorimetric sensor array.

    PubMed

    Kim, Su-Yeon; Li, Jinglei; Lim, Na-Ri; Kang, Bo-Sik; Park, Hyun-Jin

    2016-11-15

    The aim of this study was to develop a simple and rapid method based on colorimetric sensor array (CSA) for evaluation of warmed-over flavour (WOF) in cooked chicken. All samples were classified according to storage time by CSA coupled with principle component analysis (PCA) or hierarchical cluster analysis (HCA). The CSA data were used to establish prediction models with thiobarbituric acid reactive substances (TBARS), pentanal, hexanal, or heptanal associated with WOF by partial least square regression (PLSR). For the TBARS model, the coefficient of determination (rp(2)) was 0.9997 in the prediction range of 0.28-0.69mg/kg. In each of the models for pentanal, hexanal, and heptanal, all rp(2) were higher than 0.960 in the range of 0.58-2.10mg/kg, 5.50-11.69mg/kg, and 0.09-0.16mg/kg, respectively. These results demonstrate that the CSA was able to predict WOF development and to distinguish between each storage time. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Tropospheric OH and Cl levels deduced from non-methane hydrocarbon measurements in a marine site

    NASA Astrophysics Data System (ADS)

    Arsene, C.; Bougiatioti, A.; Kanakidou, M.; Bonsang, B.; Mihalopoulos, N.

    2007-09-01

    In situ continuous hourly measurements of C2-C8 non-methane hydrocarbons (NMHCS) have been performed from March to October 2006 at two coastal locations (natural and rural) on the island of Crete, in the Eastern Mediterranean. Well defined diel variations were observed for several short lived NMHCS (including ethene, propene, n-butane, n-pentane, n-hexane, 2-methyl-pentane). The daytime concentration of hydroxyl (OH) radicals estimated from these experimental data varied from 1.3×106 to ~4.0×106 radical cm-3, in good agreement with box-model simulations. In addition the relative variability of various hydrocarbon pairs (at least 7) was used to derive the tropospheric levels of Cl atoms. The Cl atom concentration has been estimated to range between 0.6×104 and 4.7×104 atom cm-3, in good agreement with gaseous hydrochloric acid (HCl) observations in the area. Such levels of Cl atoms can be of considerable importance for the oxidation capacity of the troposphere on a regional scale.

  16. Theory and Experiment of Binary Diffusion Coefficient of n-Alkanes in Dilute Gases.

    PubMed

    Liu, Changran; McGivern, W Sean; Manion, Jeffrey A; Wang, Hai

    2016-10-10

    Binary diffusion coefficients were measured for n-pentane, n-hexane, and n-octane in helium and of n-pentane in nitrogen over the temperature range of 300 to 600 K, using reversed-flow gas chromatography. A generalized, analytical theory is proposed for the binary diffusion coefficients of long-chain molecules in simple diluent gases, taking advantage of a recently developed gas-kinetic theory of the transport properties of nanoslender bodies in dilute free-molecular flows. The theory addresses the long-standing question about the applicability of the Chapman-Enskog theory in describing the transport properties of nonspherical molecular structures, or equivalently, the use of isotropic potentials of interaction for a roughly cylindrical molecular structure such as large normal alkanes. An approximate potential energy function is proposed for the intermolecular interaction of long-chain n-alkane with typical bath gases. Using this potential and the analytical theory for nanoslender bodies, we show that the diffusion coefficients of n-alkanes in typical bath gases can be treated by the resulting analytical model accurately, especially for compounds larger than n-butane.

  17. Coriolis analysis of several high-resolution infrared bands of bicyclo[111]pentane-d0 and -d1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Perry, A.; Martin, M. A.; Nibler, J. W.

    High resolution infrared absorption spectra have been analyzed for two bicyclo[1.1.1]pentane isotopologues, C5H8 (-d0) and C5H7D (-d1), where in the latter the D-atom replaces a hydrogen on the C3 symmetry axis such that the molecular symmetry is reduced from D3h to C3v. Two (a2") parallel bands, ν17 and ν18, of bicyclopentane-d0 were studied and the former was found to be profoundly affected by Coriolis coupling with the nearby (e') perpendicular band, ν11. Weaker coupling was observed between the ν18 band and the nearby ν13(e') band, for which fewer transitions could be assigned. For bicyclopentane-d1, the ν5 parallel band was alsomore » studied along with the nearby ν15(e') band to which it is coupled through a similar type of Coriolis resonance. For both isotopologues, quantum calculations (B3LYP/cc-pVTZ) done at the anharmonic level were very helpful in unraveling the complexities caused by the Coriolis interactions, provided that care is taken in identifying the effect of any Coriolis resonances in the theoretical values of aB and q rovibrational parameters. The ground state B0 constants were found to be 0.2399412(2) and 0.2267506(11) cm-1 for the -d0 and -d1 isotopologues. The difference yields an Rs substitution value of 2.0309(2) Å for the position of the axial H atom relative to the -d0 center of mass, a result in good accord with a corresponding Ra value of 2.044(6) Å from electron diffraction data. For both isotopologues, the theoretical results from the quantum calculations are in good agreement with all corresponding values determined from the spectra.« less

  18. Identification and analytical characterization of nine synthetic cathinone derivatives N-ethylhexedrone, 4-Cl-pentedrone, 4-Cl-α-EAPP, propylone, N-ethylnorpentylone, 6-MeO-bk-MDMA, α-PiHP, 4-Cl-α-PHP, and 4-F-α-PHP.

    PubMed

    Liu, Cuimei; Jia, Wei; Li, Tao; Hua, Zhendong; Qian, Zhenhua

    2017-08-01

    Clinical and forensic toxicology laboratories are continuously confronted by analytical challenges when dealing with the new psychoactive substances (NPS) phenomenon. In this study, the analytical characterization of nine synthetic cathinones is described: 2-(ethylamino)-1-phenylhexan-1-one (N-ethylhexedrone 1), 1-(4-chlorophenyl)-2-(methylamino)pentan-1-one (4-Cl-pentedrone 2), 1-(4-chlorophenyl)-2-(ethylamino)pentan-1-one (4-Cl-α-EAPP 3), 1-(3,4-methylenedioxyphenyl)-2-propylaminopropan-1-one (propylone 4), 1-(3,4-methylenedioxyphenyl)-2-ethylaminopentan-1-one (N-ethylnorpentylone 5), 1-(6-methoxy-3,4-methylenedioxyphenyl)-2-methylaminopropan-1-one (6-MeO-bk-MDMA 6), 4-methyl-1-phenyl-2-(pyrrolidin-1-yl)pentan-1-one (α-PiHP 7), 1-(4-chlorophenyl)-2-(pyrrolidin-1-yl)hexan-1-one (4-Cl-α-PHP 8), and 1-(4-fluorophenyl)-2-(pyrrolidin-1-yl)hexan-1-one (4-F-α-PHP 9). The identification was based on ultra-high-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UHPLC-QTOF-MS), gas chromatography-mass spectrometry (GC-MS), and nuclear magnetic resonance (NMR) spectroscopy. The mass-spectral fragmentations of these compounds following collision-induced dissociation (CID) and electron ionization (EI) were studied to assist forensic laboratories in identifying these compounds or other substances with similar structure in their case work. To our knowledge, no analytical data about the compounds 1-4, 7, and 8 have appeared until now, making this the first report on these compounds. The GC-MS data of 5, 6 and 9 has been reported, but this study added the LC-MS, Fourier Transform Infrared (FTIR) and NMR data for additional characterization. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  19. U.S. EPA’s Computational Toxicology Program: Innovation Powered by Chemistry (Dalton State College presentation)

    EPA Science Inventory

    Invited presentation at Dalton College, Dalton, GA to the Alliance for Innovation & Sustainability, April 20, 2017. U.S. EPA’s Computational Toxicology Program: Innovation Powered by Chemistry It is estimated that tens of thousands of commercial and industrial chemicals are ...

  20. Biodiesel Synthesis and Evaluation: An Organic Chemistry Experiment

    ERIC Educational Resources Information Center

    Bucholtz, Ehren C.

    2007-01-01

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

  1. Chemistry in the Pharmaceutical Industry

    NASA Astrophysics Data System (ADS)

    Poindexter, Graham S.; Pendri, Yadagiri; Snyder, Lawrence B.; Yevich, Joseph P.; Deshpande, Milind

    This chapter will discuss the role of chemistry within the pharmaceutical industry. Although the focus will be upon the industry within the United States, much of the discussion is equally relevant to pharmaceutical companies based in other first world nations such as Japan and those in Europe. The major objective of the pharmaceutical industry is the discovery, development, and marketing of efficacious and safe drugs for the treatment of human disease. Of course drug companies do not exist as altruistic, charitable organizations but like other share-holder owned corporations within our capitalistic society must achieve profits in order to remain viable and competitive. Thus, there exists a conundrum between the dual goals of enhancing the quality and duration of human life and that of increasing stock-holder equity. Much has been written and spoken in the lay media about the high prices of prescription drugs and the hardships this places upon the elderly and others of limited income.

  2. Trigger chemistries for better industrial formulations.

    PubMed

    Wang, Hsuan-Chin; Zhang, Yanfeng; Possanza, Catherine M; Zimmerman, Steven C; Cheng, Jianjun; Moore, Jeffrey S; Harris, Keith; Katz, Joshua S

    2015-04-01

    In recent years, innovations and consumer demands have led to increasingly complex liquid formulations. These growing complexities have provided industrial players and their customers access to new markets through product differentiation, improved performance, and compatibility/stability with other products. One strategy for enabling more complex formulations is the use of active encapsulation. When encapsulation is employed, strategies are required to effect the release of the active at the desired location and time of action. One particular route that has received significant academic research effort is the employment of triggers to induce active release upon a specific stimulus, though little has translated for industrial use to date. To address emerging industrial formulation needs, in this review, we discuss areas of trigger release chemistries and their applications specifically as relevant to industrial use. We focus the discussion on the use of heat, light, shear, and pH triggers as applied in several model polymeric systems for inducing active release. The goal is that through this review trends will emerge for how technologies can be better developed to maximize their value through industrial adaptation.

  3. Developing Professional Skills in a Third-Year Undergraduate Chemistry Course Offered in Western Australia

    NASA Astrophysics Data System (ADS)

    Dunn, Jeffrey G.; Kagi, Robert I.; Phillips, David N.

    1998-10-01

    "This unit gave me a broad industrial view of the chemical world and I am grateful for the professional skills I gained." That is the response of one graduate several years after he had taken the "Chemistry and Technology" unit that we present in the third year of the undergraduate chemistry course at Western Australia's Curtin University of Technology. Students in tertiary education are effectively "cocooned from the real world". There is a growing need for a teaching that links students to situations they will encounter upon gaining employment. The Chemistry and Technology unit has been developed over a 12-year period and is presented in the final semester of the course. It comprises six modules and is taught by lecturers from industry and the staff of the School. The Professional Practice, Consumer Chemistry, and Environmental modules are ones that most teachers could consider in their course. The other three modules are specific to Western Australia's needs, but could be modified or replaced to cater to other employment circumstances. A survey of recent graduates yielded complimentary responses to the appropriateness of such a unit in the course.

  4. A Survey of Industrial Organic Chemists: Understanding the Chemical Industry's Needs of Current Bachelor-Level Graduates

    ERIC Educational Resources Information Center

    Fair, Justin D.; Kleist, Elyse M.; Stoy, Dylan M.

    2014-01-01

    A survey was conducted of companies from the chemical industry with an emphasis on the organic division. The data include results from 377 respondents from more than 100 different companies. More than half of all undergraduates gain fulltime work in the chemical industry or government after graduating with a bachelor's degree in chemistry.…

  5. Report of the Polymer Core Course Committee: Inclusion of Polymer Topics into Undergraduate Inorganic Chemistry Courses.

    ERIC Educational Resources Information Center

    Miller, Norman E.; And Others

    1984-01-01

    Suggests polymer topics for study in inorganic chemistry courses. Commercial materials (including list of inorganic compounds utilized in polymer industry), anchored metal catalysis, polymers modified or formed by coordination, polysiloxanes, phosphazene or phosphonitrilic halide polymers, and hetergeneous polymerization catalysts are considered.…

  6. USSR Report, Chemistry

    DTIC Science & Technology

    1984-01-06

    Sep-Oct 83) ................................. ANALYTICAL CHEMISTRY Ionometric Determination of Copper in Organic Compounds S(S. L. Davydova, et al...Committee Reviews Progress in Fertilizer Industry (EKONOMICHESKAYA GAZETA, No 42, Oct 83) .................. 30 INORGANIC COMPOUNDS Speed of Ultrasound...Sep 83).. ........... .......... . . .. . . . . .... 39 NITROGEN COMPOUNDS Phototropy of Quaternary Ammonium Salts of N,N’-Bis- Substituted Diimides

  7. Chemistry for Energy Technology I. Energy Technology Series.

    ERIC Educational Resources Information Center

    Center for Occupational Research and Development, Inc., Waco, TX.

    This course in chemistry for energy technology is one of 16 courses in the Energy Technology Series developed for an Energy Conservation-and-Use Technology curriculum. Intended for use in two-year postsecondary technical institutions to prepare technicians for employment, the courses are also useful in industry for updating employees in…

  8. 78 FR 65667 - Agency Information Collection Activities; Submission for Office of Management and Budget Review...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-01

    ... Request; Guidance for Industry on Chemistry, Manufacturing, and Controls Postapproval Manufacturing... chemistry, manufacturing, and controls (CMC) postapproval manufacturing changes that FDA has determined will... Pharmaceutical Product Quality Initiative and its risk-based approach to CMC review, FDA has evaluated the types...

  9. The Impact of Biotechnology upon Chemistry in Pharmacy Schools.

    ERIC Educational Resources Information Center

    Henkel, James G.; And Others

    1990-01-01

    Applications of biotechnology to the pharmaceutical industry are examined, and its impact on the research and practical domains of medicinal and natural products chemistry is discussed. Specific curricular implications for undergraduate and graduate study in pharmacy are outlined, and suggestions for faculty development in biotechnology are made.…

  10. Assessing Process Mass Intensity and Waste via an "aza"-Baylis-Hillman Reaction

    ERIC Educational Resources Information Center

    Go´mez-Biagi, Rodolfo F.; Dicks, Andrew P.

    2015-01-01

    A synthetic procedure is outlined where upper-level undergraduate organic chemistry students perform a two-week, semimicroscale "aza"-Baylis-Hillman reaction to generate an allylic sulfonamide product. Students evaluate several green chemistry reaction metrics of industrial importance (process mass intensity (PMI), E factor, and reaction…

  11. Chemistry for Energy Technology II. Energy Technology Series.

    ERIC Educational Resources Information Center

    Center for Occupational Research and Development, Inc., Waco, TX.

    This course in chemistry for energy technology is one of 16 courses in the Energy Technology Series developed for an Energy Conservation-and-Use Technology curriculum. Intended for use in two-year postsecondary technical institutions to prepare technicians for employment, the courses are also useful in industry for updating employees in…

  12. Real World of Industrial Chemistry: The SHOP Process: An Example of Industrial Creativity.

    ERIC Educational Resources Information Center

    Reuben, Bryan; Wittcoff, Harold

    1988-01-01

    Discusses the Shell Higher Olefins Process (SHOP) in the manufacture of primary C11-C15 fatty alcohols. Offers examples and explanations of the four-step process. Gives uses for reaction products. (ML)

  13. Survey of cotton (Gossypium sp.) for non-polar, extractable hydrocarbons for use as petrochemicals and liquid fuels

    USDA-ARS?s Scientific Manuscript database

    An ontogenetic study of a commercial cotton cultivar (FiberMax 1320), grown dryland, revealed that the dry weight (DW) of leaves reached a maximum at the 1st flower stage, and then declined as bolls opened. However, % pentane soluble hydrocarbon (HC) yield continued to increase throughout the growi...

  14. Short-Term Energy Outlook Model Documentation: Petroleum Products Supply Module

    EIA Publications

    2013-01-01

    The Petroleum Products Supply Module of the Short-Term Energy Outlook (STEO) model provides forecasts of petroleum refinery inputs (crude oil, unfinished oils, pentanes plus, liquefied petroleum gas, motor gasoline blending components, and aviation gasoline blending components) and refinery outputs (motor gasoline, jet fuel, distillate fuel, residual fuel, liquefied petroleum gas, and other petroleum products).

  15. VOCs and OVOCs distribution and control policy implications in Pearl River Delta region, China

    NASA Astrophysics Data System (ADS)

    Louie, Peter K. K.; Ho, Josephine W. K.; Tsang, Roy C. W.; Blake, Donald R.; Lau, Alexis K. H.; Yu, Jian Zhen; Yuan, Zibing; Wang, Xinming; Shao, Min; Zhong, Liuju

    2013-09-01

    Ambient air measurements of volatile organic compounds (VOCs) and oxygenated volatile organic compounds (OVOCs) were conducted and characterised during a two-year grid study in the Pearl River Delta (PRD) region of southern China. The present grid study pioneered the systematic investigation of the nature and characteristics of complex VOC and OVOC sources at a regional scale. The largest contributing VOCs, accounting over 80% of the total VOCs mixing ratio, were toluene, ethane, ethyne, propane, ethene, butane, benzene, pentane, ethylbenzene, and xylenes. Sub-regional VOC spatial characteristics were identified, namely: i) relatively fresh pollutants, consistent with elevated vehicular and industrial activities, around the PRD estuary; and ii) a concentration gradient with higher mixing ratios of VOCs in the west as compared with the eastern part of PRD. Based on alkyl nitrate aging determination, a high hydroxyl radical (OH) concentration favoured fast hydrocarbon reactions and formation of locally produced ozone. The photochemical reactivity analysis showed aromatic hydrocarbons and alkenes together consisted of around 80% of the ozone formation potential (OFP) among the key VOCs. We also found that the OFP from OVOCs should not be neglected since their OFP contribution was more than one-third of that from VOCs alone. These findings support the choice of current air pollution control policy which focuses on vehicular sources but warrants further controls. Industrial emissions and VOCs emitted by solvents should be the next targets for ground-level ozone abatement.

  16. Integrating Chemistry: Crossing the Millennium Divide.

    PubMed

    Housecroft, Catherine E

    2018-02-01

    A personal account of the development of two University level chemistry books is presented. The account focuses on ways to integrate the traditional branches of chemistry into a textbook that captures the imagination of students and relates chemical principles and fundamental topics to environmental, medicinal, biological and industrial applications. The ways in which teaching methods have changed over two decades and how web-based resources can be used to improve the communication of chemical (in particular structural) concepts are highlighted.

  17. Synthesis of Hollow Gold-Silver Alloyed Nanoparticles: A "Galvanic Replacement" Experiment for Chemistry and Engineering Students

    ERIC Educational Resources Information Center

    Jenkins, Samir V.; Gohman, Taylor D.; Miller, Emily K.; Chen, Jingyi

    2015-01-01

    The rapid academic and industrial development of nanotechnology has led to its implementation in laboratory teaching for undergraduate-level chemistry and engineering students. This laboratory experiment introduces the galvanic replacement reaction for synthesis of hollow metal nanoparticles and investigates the optical properties of these…

  18. Teaching Analytical Method Transfer through Developing and Validating Then Transferring Dissolution Testing Methods for Pharmaceuticals

    ERIC Educational Resources Information Center

    Kimaru, Irene; Koether, Marina; Chichester, Kimberly; Eaton, Lafayette

    2017-01-01

    Analytical method transfer (AMT) and dissolution testing are important topics required in industry that should be taught in analytical chemistry courses. Undergraduate students in senior level analytical chemistry laboratory courses at Kennesaw State University (KSU) and St. John Fisher College (SJFC) participated in development, validation, and…

  19. Ionic Liquids and Green Chemistry: A Lab Experiment

    ERIC Educational Resources Information Center

    Stark, Annegret; Ott, Denise; Kralisch, Dana; Kreisel, Guenter; Ondruschka, Bernd

    2010-01-01

    Although ionic liquids have been investigated as solvents for many applications and are starting to be used in industrial processes, only a few lab experiments are available to introduce students to these materials. Ionic liquids have been discussed in the context of green chemistry, but few investigations have actually assessed the degree of…

  20. 40 Low-Waste, Low-Risk Chemistry Labs.

    ERIC Educational Resources Information Center

    Dougan, David

    This resource book contains 40 chemistry labs and provides a single solution to the problems of purchase, storage, use, and disposal of chemicals. The text is designed to be used alone or integrated with current textbooks. A mixture of microchemistry and macrochemistry is used to provide variety and reflects trends in research and industry. Most…

  1. Applications of Pulsed Power in Advanced Oxidation and Reduction Processes for Pollution Control

    DTIC Science & Technology

    1993-06-01

    electrical driver pulse width and rise time, electrical drive circuit coupling to plasma cells, and the role of UV light in the plasma chemistry and...will permit industrial service. Basic understanding of the plasma chemistry has evolved to the point where trends and equipment scaling can be

  2. Evaluation of Future Blogs. Final Report

    ERIC Educational Resources Information Center

    Haines, Ben; Straw, Suzanne

    2008-01-01

    Future Blogs was developed through collaboration between the Royal Society of Chemistry and The Brightside Trust. It is an innovative e-mentoring scheme that links pupils studying chemistry with mentors from universities or industry and is based on the Bright Journals e-mentoring programme (an e-mentoring scheme targeted at 14-18 year olds…

  3. Quantum chemistry in environmental pesticide risk assessment.

    PubMed

    Villaverde, Juan J; López-Goti, Carmen; Alcamí, Manuel; Lamsabhi, Al Mokhtar; Alonso-Prados, José L; Sandín-España, Pilar

    2017-11-01

    The scientific community and regulatory bodies worldwide, currently promote the development of non-experimental tests that produce reliable data for pesticide risk assessment. The use of standard quantum chemistry methods could allow the development of tools to perform a first screening of compounds to be considered for the experimental studies, improving the risk assessment. This fact results in a better distribution of resources and in better planning, allowing a more exhaustive study of the pesticides and their metabolic products. The current paper explores the potential of quantum chemistry in modelling toxicity and environmental behaviour of pesticides and their by-products by using electronic descriptors obtained computationally. Quantum chemistry has potential to estimate the physico-chemical properties of pesticides, including certain chemical reaction mechanisms and their degradation pathways, allowing modelling of the environmental behaviour of both pesticides and their by-products. In this sense, theoretical methods can contribute to performing a more focused risk assessment of pesticides used in the market, and may lead to higher quality and safer agricultural products. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  4. Automated Classification and Analysis of Non-metallic Inclusion Data Sets

    NASA Astrophysics Data System (ADS)

    Abdulsalam, Mohammad; Zhang, Tongsheng; Tan, Jia; Webler, Bryan A.

    2018-05-01

    The aim of this study is to utilize principal component analysis (PCA), clustering methods, and correlation analysis to condense and examine large, multivariate data sets produced from automated analysis of non-metallic inclusions. Non-metallic inclusions play a major role in defining the properties of steel and their examination has been greatly aided by automated analysis in scanning electron microscopes equipped with energy dispersive X-ray spectroscopy. The methods were applied to analyze inclusions on two sets of samples: two laboratory-scale samples and four industrial samples from a near-finished 4140 alloy steel components with varying machinability. The laboratory samples had well-defined inclusions chemistries, composed of MgO-Al2O3-CaO, spinel (MgO-Al2O3), and calcium aluminate inclusions. The industrial samples contained MnS inclusions as well as (Ca,Mn)S + calcium aluminate oxide inclusions. PCA could be used to reduce inclusion chemistry variables to a 2D plot, which revealed inclusion chemistry groupings in the samples. Clustering methods were used to automatically classify inclusion chemistry measurements into groups, i.e., no user-defined rules were required.

  5. User-friendly chemistry takes center stage at ACS meeting

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pool, R.

    1992-09-11

    These days it seems that what chemistry needs more than anything else is a good p.r. agent. If you ask John or Joan Q. Public about the accomplishments of the chemical industry, chances are they'll mention Love Canal, CFCs destroying the ozone layer, or carcinogens in food. However, if the national meeting of the American Chemical Society in Washington, D.C., 2 weeks ago is any indication, chemists are working hard to fix the image problem. Nearly all of the two dozen press conferences held during the meeting focused on food, health topics, environment-friendly technology, or some other subject close tomore » consumers' hearts. And the scientific talks themselves reflected the same interests, with sessions such as Environmental Successes in the Chemical Industry', Food Phytochemicals for Cancer Prevention', Chemistry of Electrophilic Metal Complexes', New Advances in Polyolefin Polymers', Zapping acid rain with microwaves.'« less

  6. Study and modeling of finite rate chemistry effects in turbulent non-premixed flames

    NASA Technical Reports Server (NTRS)

    Vervisch, Luc

    1993-01-01

    The development of numerical models that reflect some of the most important features of turbulent reacting flows requires information about the behavior of key quantities in well defined combustion regimes. In turbulent flames, the coupling between turbulent and chemical processes is so strong that it is extremely difficult to isolate the role played by one individual physical phenomenon. Direct numerical simulation (hereafter DNS) allows us to study in detail the turbulence-chemistry interaction in some restricted but completely defined situations. Globally, non-premixed flames are controlled by two limiting regimes: the fast chemistry case, where the turbulent flame can be pictured as a random distribution of local chemical equilibrium problems; and the slow chemistry case, where the chemistry integrates in time the turbulent fluctuations. The Damkoehler number, ratio of a mechanical time scale to chemical time scale, is used to distinguish between these regimes. Today most of the industrial computer codes are able to perform predictions in the hypothesis of local equilibrium chemistry using a presumed shape for the probability density function (pdt) of the conserved scalar. However, the finite rate chemistry situation is of great interest because industrial burners usually generate regimes in which, at some points, the flame is undergoing local extinction or at least non-equilibrium situations. Moreover, this variety of situations strongly influences the production of pollutants. To quantify finite rate chemistry effect, the interaction between a non-premixed flame and a free decaying turbulence is studied using DNS. The attention is focused on the dynamic of extinction, and an attempt is made to quantify the effect of the reaction on the small scale mixing process. The unequal diffusivity effect is also addressed. Finally, a simple turbulent combustion model based on the DNS observations and tractable in real flow configurations is proposed.

  7. Tropospheric Bromine Chemistry: Implications for Present and Pre-industrial Ozone and Mercury

    NASA Technical Reports Server (NTRS)

    Parella, J. P.; Jacob, D. J.; Liang, Q.; Zhang, Y.; Mickley, L. J.; Miller, B.; Evans, M. J.; Yang, X.; Pyle, J. A.; Theys, N.; hide

    2012-01-01

    We present a new model for the global tropospheric chemistry of inorganic bromine (Bry) coupled to oxidant-aerosol chemistry in the GEOS-Chem chemical transport model (CTM). Sources of tropospheric Bry include debromination of sea-salt aerosol, photolysis and oxidation of short-lived bromocarbons, and transport from the stratosphere. Comparison to a GOME-2 satellite climatology of tropospheric BrO columns shows that the model can reproduce the observed increase of BrO with latitude, the northern mid-latitudes maximum in winter, and the Arctic maximum in spring. This successful simulation is contingent on the HOBr + HBr reaction taking place in aqueous aerosols and ice clouds. Bromine chemistry in the model decreases tropospheric ozone mixing ratios by <1-8 nmol/mol (6.5% globally), with the largest effects in the northern extratropics in spring. The global mean tropospheric OH concentration decreases by 4 %. Inclusion of bromine chemistry improves the ability of global models (GEOS-Chem and p-TOMCAT) to simulate observed 19th-century ozone and its seasonality. Bromine effects on tropospheric ozone are comparable in the present-day and pre-industrial atmospheres so that estimates of anthropogenic radiative forcing are minimally affected. Br atom concentrations are 40% higher in the pre-industrial atmosphere due to lower ozone, which would decrease by a factor of 2 the atmospheric lifetime of elemental mercury against oxidation by Br. This suggests that historical anthropogenic mercury emissions may have mostly deposited to northern mid-latitudes, enriching the corresponding surface reservoirs. The persistent rise in background surface ozone at northern mid-latitudes during the past decades could possibly contribute to the observations of elevated mercury in subsurface waters of the North Atlantic.

  8. Reconstructing Early Industrial Contributions to Legacy Trace Metal Contamination in Southwestern Pennsylvania.

    PubMed

    Rossi, Robert J; Bain, Daniel J; Hillman, Aubrey L; Pompeani, David P; Finkenbinder, Matthew S; Abbott, Mark B

    2017-04-18

    Early industrial trace metal loadings are poorly characterized but potentially substantial sources of trace metals to the landscape. The magnitude of legacy contamination in southwestern Pennsylvania, the cradle of North American fossil fuel industrialization, is reconstructed from trace metal concentrations in a sediment core with proxies including major and trace metal chemistry, bulk density, and magnetic susceptibility. Trace metal chemistry in this sediment record reflects 19th and 20th century land use and industry. In particular, early 19th century arsenic loadings to the lake are elevated from pesticides used by early European settlers at a lakeside tannery. Later, sediment barium concentrations rise, likely reflecting the onset of acidic mine drainage from coal operations. Twentieth century zinc, cadmium, and lead concentrations are dominated by emissions from the nearby, infamous Donora Zinc Works yet record both the opening of a nearby coal-fired power plant and amendments to the Clean Air Act. The impact of early industry is substantial and rivals more recent metal fluxes, resulting in a significant potential source of contaminated sediments. Thus, modern assessments of trace metal contamination cannot ignore early industrial inputs, as the potential remobilization of legacy contamination would impact ecosystem and human health.

  9. 21 CFR 178.3010 - Adjuvant substances used in the manufacture of foamed plastics.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... prescribed limitations: List of substances Limitations Azodicarbonamide For use as a blowing agent in pol... agent in polystyrene. Isopentane For use as a blowing agent in polystyrene. n-Pentane Do. 1,1,2,2-Tetra-chloroethylene For use only as a blowing agent adjuvant in polystyrene at a level not to exceed 0.3 percent by...

  10. 21 CFR 178.3010 - Adjuvant substances used in the manufacture of foamed plastics.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... prescribed limitations: List of substances Limitations Azodicarbonamide For use as a blowing agent in pol... agent in polystyrene. Isopentane For use as a blowing agent in polystyrene. n-Pentane Do. 1,1,2,2-Tetra-chloroethylene For use only as a blowing agent adjuvant in polystyrene at a level not to exceed 0.3 percent by...

  11. 21 CFR 178.3010 - Adjuvant substances used in the manufacture of foamed plastics.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... prescribed limitations: List of substances Limitations Azodicarbonamide For use as a blowing agent in pol... agent in polystyrene. Isopentane For use as a blowing agent in polystyrene. n-Pentane Do. 1,1,2,2-Tetra-chloroethylene For use only as a blowing agent adjuvant in polystyrene at a level not to exceed 0.3 percent by...

  12. [1,3-Bis(diphenyl-phosphino)pentane-κP,P']tetra-carbonyl-chromium(0).

    PubMed

    Shawkataly, Omar Bin; Thangadurai, Daniel T; Pankhi, Mohd Aslam A; Shahinoor Dulal Islam, S M; Fun, Hoong-Kun

    2009-02-04

    In the title compound, [Cr(C(29)H(30)P(2))(CO)(4)], the Cr atom is octa-hedrally coordinated by four carbonyl ligands and one bidentate phosphine ligand, which is bounded as a chelate in a cis position. The average Cr-P and Cr-C bond lengths are 2.377 and 1.865 Å, respectively.

  13. The Mechanochemical Reaction of Palladium(II) Chloride with a Bidentate Phosphine

    ERIC Educational Resources Information Center

    Berry, David E.; Carrie, Philippa; Fawkes, Kelli L.; Rebner, Bruce; Xing, Yao

    2010-01-01

    This experiment describes the reaction of palladium(II) chloride with 1,5-bis(diphenylphosphino)pentane by grinding the two powders together in the solid state. The product is the precursor for the metalation reaction at one of the methylene carbon atoms of the ligand's backbone. The final product is known to be a catalyst for Suzuki-Miyaura…

  14. Super Hydrides.

    DTIC Science & Technology

    1985-03-07

    hydroboration of alkynes with BHBr 2 .SMe2 react with water , giving the corresponding alkenylboronic acids and with alcohols and glycols to give the...of ester by carrying out the reaction in pentane from which the water component separates. This procedure does away with the necessity of azeotrope... distillation of a ternary mixture, extensively used previously for the esterification of boronic acids. We previously demonstrdted that treatment of

  15. An improved molecular dynamics algorithm to study thermodiffusion in binary hydrocarbon mixtures

    NASA Astrophysics Data System (ADS)

    Antoun, Sylvie; Saghir, M. Ziad; Srinivasan, Seshasai

    2018-03-01

    In multicomponent liquid mixtures, the diffusion flow of chemical species can be induced by temperature gradients, which leads to a separation of the constituent components. This cross effect between temperature and concentration is known as thermodiffusion or the Ludwig-Soret effect. The performance of boundary driven non-equilibrium molecular dynamics along with the enhanced heat exchange (eHEX) algorithm was studied by assessing the thermodiffusion process in n-pentane/n-decane (nC5-nC10) binary mixtures. The eHEX algorithm consists of an extended version of the HEX algorithm with an improved energy conservation property. In addition to this, the transferable potentials for phase equilibria-united atom force field were employed in all molecular dynamics (MD) simulations to precisely model the molecular interactions in the fluid. The Soret coefficients of the n-pentane/n-decane (nC5-nC10) mixture for three different compositions (at 300.15 K and 0.1 MPa) were calculated and compared with the experimental data and other MD results available in the literature. Results of our newly employed MD algorithm showed great agreement with experimental data and a better accuracy compared to other MD procedures.

  16. Evaluation of a locally homogeneous flow model of spray combustion

    NASA Technical Reports Server (NTRS)

    Mao, C. P.; Szekely, G. A., Jr.; Faeth, G. M.

    1980-01-01

    A model of spray combustion which employs a second-order turbulence model was developed. The assumption of locally homogeneous flow is made, implying infinitely fast transport rates between the phase. Measurements to test the model were completed for a gaseous n-propane flame and an air atomized n-pentane spray flame, burning in stagnant air at atmospheric pressure. Profiles of mean velocity and temperature, as well as velocity fluctuations and Reynolds stress, were measured in the flames. The predictions for the gas flame were in excellent agreement with the measurements. The predictions for the spray were qualitatively correct, but effects of finite rate interphase transport were evident, resulting in a overstimation of the rate development of the flow. Predictions of spray penetration length at high pressures, including supercritical combustion conditions, were also completed for comparison with earlier measurements. Test conditions involved a pressure atomized n-pentane spray, burning in stagnant air at pressures of 3, 5, and 9 MPa. The comparison between predictions and measurements was fair. This is not a very sensitive test of the model, however, and further high pressure experimental and theoretical results are needed before a satisfactory assessment of the locally homogeneous flow approximation can be made.

  17. Analysis of a new drug of abuse: cathinone derivative 1-(3,4-dimethoxyphenyl)-2-(ethylamino)pentan-1-one.

    PubMed

    Weiß, Jennifer A; Taschwer, Magdalena; Kunert, Olaf; Schmid, Martin G

    2015-03-01

    Recently, novel psychoactive drugs for human abuse such as amphetamines, phenethylamines, benzofuries, and tryptamines, cathinones have gained high popularity. These designer drugs are mainly sold via online stores as "bath salts" and are labeled "not for human consumption." Due to the novelty of the compounds, only a little information about pharmacology, toxicology, and the long-term damage they may cause is available. Moreover, there are only few analytical methods for their identification and analysis. Among new cathinone derivatives, 1-(3,4-dimethoxyphenyl)-2-(ethylamino)pentan-1-one (DL-4662), became available via an internet shop. A sample of this compound was purchased and investigated. The first aim of our study was an identity check by NMR spectroscopy and gas chromatography with mass spectrometry. As many of the recreational drugs are chiral and are mainly sold as racemates, a further goal of our research was enantioseparation by gas chromatography with mass spectrometry and high-performance liquid chromatography with UV detection, to prove whether DL-4662 was traded enantiomerically pure or as racemic mixture. Both chiral separation methods showed the presence of a racemate. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Preparation of tyrosinase inhibitors and antibrowning agents using green technology.

    PubMed

    Dong, Xue; Zhang, Yinan; He, Jia-Liang; Zhang, Shuang; Zeng, Mao-Mao; Chen, Jie; Zheng, Zong-Ping

    2016-04-15

    Chalcones and their derivatives have attracted great interests in recent years for their comprehensive biological activities. In this study, 2,4,2',4'-tetrahydroxychalcone and its two derivatives, 1,3,5-tris-(2,4-dihydroxy-phenyl)pentane-1,5-dione (new compound) and 7,2',4'-trihydroxyflavanone, were synthesized through one-pot green procedure catalyzed by boric acid in polyethylene glycol 400. Their structures were identified by ESI-MS and NMR spectral. Tyrosinase inhibitory activity and antibrowning test results showed that compounds 1-3 exhibited strong tyrosinase inhibitory activities and significant antibrowning effects on the fresh-cut lotus root slices at room temperature in 48 h. Among them, 0.01% 1,3,5-tris-(2,4-dihydroxy-phenyl)pentane-1,5-dione combined with 0.5% VC showed the best antibrowning ability. In brief, this study offers a protocol for one-pot green synthesis of high efficiency tyrosinase inhibitors which may be suitable as antibrowning agents for fresh-cut vegetables. More important, this study developed a new type of 1,5-dione derivative which may serve as new lead structures for novel tyrosinase inhibitors discovery. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Expanding GREENSCOPE beyond the Gate: A Green Chemistry and Life-Cycle Perspective

    EPA Science Inventory

    Industrial processes, particularly those within the chemical industry, contribute products and services to improve and increase society’s quality of life. However, the transformation of raw materials into their respective final goods involves the consumption of mass and energy an...

  20. From coal to DDT: the history of the development of the pesticide DDT from synthetic dyes till Silent Spring.

    PubMed

    Jarman, Walter M; Ballschmiter, Karlheinz

    2012-12-01

    The controversial pesticide DDT arose out of a number of practical and conceptual developments in science and industry during the nineteenth and twentieth centuries. Here we trace its story back to experiments involving the industrial by-product coal tar, proceed to the development of modern organic chemistry and the establishment of an advanced dye industry, and go on to chart the attempt to identify and synthesize chemicals capable of killing the insects involved in human and crop diseases. This paper argues that work on the chemistry of coal tar played a significant role in the history of DDT because it helped bring about the scientific ideas and the practical objectives that led chemists to embark on the search for pesticides. It concludes by examining the Swiss-German DDT production industry in the early 1940s and the subsequent condemnation of DDT by an environmental movement epitomized by Rachel Carson's Silent Spring. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Fogwater chemistry in a wood-burning community, western Oregon.

    PubMed

    Muir, P S

    1991-01-01

    Fogwater chemistry in Corvallis, Oregon, a wood-burning community (pop. approximately 43,000) was compared with the chemistry of fogwater collected in more remote and in more highly industrialized areas. The fogwater was not acidic (median pH = 5.7) and was usually dominated by SO4=, NO3-, and NH4+ whose concentrations were generally lower than in fogwater in other urban areas but higher than in remote areas. Concentrations of formic and acetic acids (medians = 61 and 52 microN, respectively) were comparable to those in fogwater in Los Angeles, California and were typically much higher than concentrations in fogwater from more remote areas. Formate and acetate concentrations were often comparable to those of SO4= and NO3-. Formaldehyde concentrations (range = 0.4-3.0 mg L-1) were comparable to those in fogwater in some urban areas of southern California, yet lower than concentrations in highly industrialized areas of southern California. Because concentrations of organic compounds in Corvallis fogwater were often comparable to those in larger urban areas, sources in addition to motor vehicles must be important in Corvallis. Additional sources may be natural and anthropogenic, the latter including residential wood burning and wood products industries.

  2. Ethics in Science: The Unique Consequences of Chemistry.

    PubMed

    Kovac, Jeffrey

    2015-01-01

    This article discusses the ethical issues unique to the science and practice of chemistry. These issues arise from chemistry's position in the middle between the theoretical and the practical, a science concerned with molecules that are of the right size to directly affect human life. Many of the issues are raised by the central activity of chemistry--synthesis. Chemists make thousands of new substances each year. Many are beneficial, but others are threats. Since the development of the chemical industry in the nineteenth century, chemistry has contributed to the deterioration of the environment but has also helped to reduce pollution. Finally, we discuss the role of codes of ethics and whether the current codes of conduct for chemists are adequate for the challenges of today's world.

  3. PREFACE: 10th Joint Conference on Chemistry

    NASA Astrophysics Data System (ADS)

    2016-02-01

    The 10th Joint Conference on Chemistry is an international conference organized by 4 chemistry departments of 4 universities in central Java, Indonesia. The universities are Sebelas Maret University, Diponegoro University, Semarang State University and Soedirman University. The venue was at Solo, Indonesia, at September 8-9, 2015. The total conference participants are 133 including the invited speakers. The conference emphasized the multidisciplinary chemical issue and impact of today's sustainable chemistry which covering the following topics: • Material innovation for sustainable goals • Development of renewable and sustainable energy based on chemistry • New drug design, experimental and theoretical methods • Green synthesis and characterization of material (from molecule to functionalized materials) • Catalysis as core technology in industry • Natural product isolation and optimization

  4. Polyurethane Foams for Thermal Insulation Uses Produced from Castor Oil and Crude Glycerol Biopolyols.

    PubMed

    Carriço, Camila S; Fraga, Thaís; Carvalho, Vagner E; Pasa, Vânya M D

    2017-07-02

    Rigid polyurethane foams were synthesized using a renewable polyol from the simple physical mixture of castor oil and crude glycerol. The effect of the catalyst (DBTDL) content and blowing agents in the foams' properties were evaluated. The use of physical blowing agents (cyclopentane and n-pentane) allowed foams with smaller cells to be obtained in comparison with the foams produced with a chemical blowing agent (water). The increase of the water content caused a decrease in density, thermal conductivity, compressive strength, and Young's modulus, which indicates that the increment of CO₂ production contributes to the formation of larger cells. Higher amounts of catalyst in the foam formulations caused a slight density decrease and a small increase of thermal conductivity, compressive strength, and Young's modulus values. These green foams presented properties that indicate a great potential to be used as thermal insulation: density (23-41 kg·m -3 ), thermal conductivity (0.0128-0.0207 W·m -1 ·K -1 ), compressive strength (45-188 kPa), and Young's modulus (3-28 kPa). These biofoams are also environmentally friendly polymers and can aggregate revenue to the biodiesel industry, contributing to a reduction in fuel prices.

  5. Chemical and Sensory Characterization of Oxidative Changes in Roasted Almonds Undergoing Accelerated Shelf Life.

    PubMed

    Franklin, Lillian M; Chapman, Dawn M; King, Ellena S; Mau, Mallory; Huang, Guangwei; Mitchell, Alyson E

    2017-03-29

    In almonds, there is no standard method for detecting oxidative changes and little data correlating consumer perception with chemical markers of rancidity. To address this, we measured peroxide values (PV), free fatty acid values (FFAs), conjugated dienes, tocopherols, headspace volatiles, and consumer hedonic response in light roasted (LR) and dark roasted (DR) almonds stored under conditions that promote rancidity development over 12 months. Results demonstrate that, although rancidity develops at different rates in LR and DR almonds, consumer liking was not significantly different between LR and DR almonds. Average hedonic ratings of almonds were found to fall below a designated acceptable score of 5 ("neither like nor dislike") by 6 months of storage. This did not correspond with recommended industry rejection standard of PV < 5 mequiv peroxide/kg oil and FFA < 1.5% oleic. FFAs remain well below <1.5% oleic during storage, indicating that FFAs are not a good marker of rancidity in roasted almonds stored in low humidity environments. Regression of consumer liking to concentration of rancidity indicators revealed that selected headspace volatiles, including heptanal, octanal, nonanal, 2-octenal, 2-heptanone, 2-pentylfuran, hexanal, and pentanal, had a better correlation with liking than did nonvolatile indicators.

  6. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Green, D.W.; Heinrich, R.R.; Graczyk, D.G.

    The purpose of this report is to summarize the activities of the Analytical Chemistry Laboratory (ACL) at Argonne National Laboratory (ANL) for fiscal year 1988 (October 1987 through September 1988). The Analytical Chemistry Laboratory is a full-cost recovery service center, with the primary mission of providing a broad range of analytical chemistry support services to the scientific and engineering programs at ANL. In addition, the ACL conducts a research program in analytical chemistry, works on instrumental and methods development, and provides analytical services for governmental, educational, and industrial organizations. The ACL handles a wide range of analytical problems, from routinemore » standard analyses to unique problems that require significant development of methods and techniques.« less

  7. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Green, D.W.; Heinrich, R.R.; Graczyk, D.G.

    The purpose of this report is to summarize the activities of the Analytical Chemistry Laboratory (ACL) at Argonne National Laboratory (ANL) for Fiscal Year 1989 (October 1988 through September 1989). The Analytical Chemistry Laboratory is a full-cost-recovery service center, with the primary mission of providing a broad range of analytical chemistry support services to the scientific and engineering programs at ANL. In addition, the ACL conducts a research program in analytical chemistry, works on instrumental and methods development, and provides analytical services for governmental, educational, and industrial organizations. The ACL handles a wide range of analytical problems, from routine standardmore » analyses to unique problems that require significant development of methods and techniques.« less

  8. Copolymerization of Epoxides and CO[subscript 2]: Polymer Chemistry for Incorporation in Undergraduate Inorganic Chemistry

    ERIC Educational Resources Information Center

    Darensbourg, Donald J.

    2017-01-01

    Because fossil fuels are a nonrenewable resource, alternative sources of chemical carbon will be necessary as petroleum based chemicals decline during the 21st century. Carbon dioxide can serve as a source of carbon for the synthesis of useful chemicals, thereby contributing to a sustainable chemical industry. A promising technology for…

  9. Hydrocarbons. Independent Learning Project for Advanced Chemistry (ILPAC). Unit O1.

    ERIC Educational Resources Information Center

    Inner London Education Authority (England).

    This unit on hydrocarbons is one of 10 first year units produced by the Independent Learning Project for Advanced Chemistry (ILPAC). The unit is divided into sections dealing with alkanes, alkenes, alkynes, arenes, and several aspects of the petroleum industry. Two experiments, exercises (with answers), and pre- and post-tests are included.…

  10. Academic Women Chemists in the 20th Century: Past, Present, Projections.

    ERIC Educational Resources Information Center

    Roscher, Nina Matheny; Cavanaugh, Margaret A.

    1987-01-01

    The number of women obtaining degrees in chemistry has increased and many indicators suggest that the trend will continue. The percentage of women obtaining BS, MS, and PhD degrees in chemistry is also expected to continue to rise. Doctoral women chemists are beginning to be distributed in governmental, academic, and industrial workplaces in the…

  11. Hydrodésazotation de la pyridine sous pression atmosphérique catalysée par des oxynitrures de Ni, Mo, et des oxynitrures mixtes MoNi, MoPNi, AlNi et AlPNi

    NASA Astrophysics Data System (ADS)

    Elkamel, K.; Elidrissi, M.; Yacoubi, A.; Nadiri, A.; Abouarnadasse, S.

    1998-11-01

    Hydrodenitrogenation of pyridine has been realised, under atmospheric pressure, in the presence of oxynitride catalysts of molybdenum, nickel and their solid solutions as well as on mixed catalysts MoNi, MoPNi, AlNi and AlPNi. In all cases, the main reaction products are n-pentane and N-pentylpiperidine, at any conversion. Kinetic results suggest that the conversion of pyridine, on nickel oxynitride, proceeds through successive steps with hydrogenation as rate-limiting. Molybdenum oxynitride and Mo-Ni-N solid solutions tested in the temperature range 500 circC-450 circC, showed a good structural and catalytic stability, but a low catalytic activity. On the other hand, nickel oxynitride catalyst yielded higher activity at much lower temperatures (190 circC-250 circC). X-rays analysis indicates that the used catalyst was entirely reduced to metallic nickel, which is the active phase. Under the same experimental conditions, mixed catalysts are relatively less active but more selective than nickel oxynitride into n-pentane formation. La réaction d'hydrodésazotation de la pyridine a été réalisée, sous pression atmosphérique, en présence de catalyseurs oxynitrures de molybdène, de nickel et leurs solutions solides ainsi que sur les catalyseurs mixtes MoNi, MoPNi, AlNi et AlPNi. Dans tous les cas, les principaux produits de réaction observés sont le n-pentane et la N- pentylpipéridine, quel que soit le taux de conversion. Les résultats cinétiques obtenus en régime intégral, en présence de l'oxynitrure de nickel, suggèrent un schéma réactionnel successif où l'hydrogénation de la pyridine serait l'étape limitante. L'oxynitrure de molybdène et les solutions solides Mo-Ni-N, testés à des températures supérieures ou égales à 500 circC, ont montré une bonne stabilité catalytique et structurale mais une faible activité catalytique. En revanche, l'oxynitrure de nickel présente une activité catalytique plus importante à des températures de réaction beaucoup plus basses (190 circC 250 circC). Cependant, l'analyse aux rayons X du catalyseur usagé, indique qu'il est entièrement réduit à l'état métallique; ceci laisse supposer que le nickel métallique est la phase active. Dans les mêmes conditions expérimentales, les catalyseurs mixtes sont relativement moins actifs que l'oxynitrure de nickel, mais plus sélectifs vis-à-vis de la formation du n-pentane.

  12. Industrial Chemistry, Science (Experimental): 5316.07.

    ERIC Educational Resources Information Center

    Scholz, Robert

    This unit of instruction presents some important and interesting processes carried on daily in industry and which result in products with which the student is familiar. The student will be responsible for learning some reactions involving these chemical processes and the quantitative calculations of these reactions. Fractional distillation,…

  13. Chemical Pathways of Corticosteroids, Industrial Synthesis from Sapogenins.

    PubMed

    Herráiz, Ignacio

    2017-01-01

    Corticosteroids are products of high industrial and commercial importance. There are dozens of different synthesis published for all of them. Some are coming from academia and some from industry. Here, industrial processes for the synthesis of prednisone, prednisolone, hydrocortisone, dexamethasone, betamethasone, and methylprednisolone are described. The starting material is diosgenin and the desired molecules are reached due to a good combination of chemistry and biotechnology that was developed along the second part of the twentieth century.

  14. Properties, performance and associated hazards of state-of-the-art durable water repellent (DWR) chemistry for textile finishing.

    PubMed

    Holmquist, H; Schellenberger, S; van der Veen, I; Peters, G M; Leonards, P E G; Cousins, I T

    2016-05-01

    Following the phase-out of long-chain per- and polyfluoroalkyl substances (PFASs), the textile industry had to find alternatives for side-chain fluorinated polymer based durable water repellent (DWR) chemistries that incorporated long perfluoroalkyl side chains. This phase-out and subsequent substitution with alternatives has resulted in a market where both fluorinated and non-fluorinated DWRs are available. These DWR alternatives can be divided into four broad groups that reflect their basic chemistry: side-chain fluorinated polymers, silicones, hydrocarbons and other chemistries (includes dendrimer and inorganic nanoparticle chemistries). In this critical review, the alternative DWRs are assessed with regards to their structural properties and connected performance, loss and degradation processes resulting in diffuse environmental emissions, and hazard profiles for selected emitted substances. Our review shows that there are large differences in performance between the alternative DWRs, most importantly the lack of oil repellence of non-fluorinated alternatives. It also shows that for all alternatives, impurities and/or degradation products of the DWR chemistries are diffusively emitted to the environment. Our hazard ranking suggests that hydrocarbon based DWR is the most environmentally benign, followed by silicone and side-chain fluorinated polymer-based DWR chemistries. Industrial commitments to reduce the levels of impurities in silicone based and side-chain fluorinated polymer based DWR formulations will lower the actual risks. There is a lack of information on the hazards associated with DWRs, in particular for the dendrimer and inorganic nanoparticle chemistries, and these data gaps must be filled. Until environmentally safe alternatives, which provide the required performance, are available our recommendation is to choose DWR chemistry on a case-by-case basis, always weighing the benefits connected to increased performance against the risks to the environment and human health. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Water Pollution: Part I, Municipal Wastewaters; Part II, Industrial Wastewaters.

    ERIC Educational Resources Information Center

    Fowler, K. E. M.

    This publication is an annotated bibliography of municipal and industrial wastewater literature. This publication consists of two parts plus appendices. Part one is entitled Municipal Wastewaters and includes publications in such areas as health effects of polluted waters, federal policy and legislation, biology and chemistry of polluted water,…

  16. Egyptology in the Service of Learning Chemistry in Industrial Engineering

    ERIC Educational Resources Information Center

    Giménez, Javier

    2014-01-01

    Ancient cultures or civilizations carried out different technological improvements without the knowledge of the scientific processes involved. At the Escola Tècnica Superior d'Enginyeria Industrial de Barcelona (ETSEIB), some courses deal with the technological achievements in the antiquity and, in particular, one course deals with the…

  17. Analytical evaluation of current starch methods used in the international sugar industry: Part I

    USDA-ARS?s Scientific Manuscript database

    Several analytical starch methods currently exist in the international sugar industry that are used to prevent or mitigate starch-related processing challenges as well as assess the quality of traded end-products. These methods use simple iodometric chemistry, mostly potato starch standards, and uti...

  18. 21 CFR 178.3010 - Adjuvant substances used in the manufacture of foamed plastics.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Limitations Azodicarbonamide For use as a blowing agent in pol-yethylene complying with item 2.1 in § 177.1520...-Difluoroethane (CAS Reg. No. 75-37-6) For use as a blowing agent in polystyrene. Isopentane For use as a blowing agent in polystyrene. n-Pentane Do. 1,1,2,2-Tetra-chloroethylene For use only as a blowing agent...

  19. International Traffic in Arms Regulations (ITAR), (22 CFR 120-130)

    DTIC Science & Technology

    1996-06-01

    Butadienenitrileoxide (BNO); (6) Catocene, N-butyl- ferrocene and other ferrocene derivatives; (7) 3-nitraza-l,5 pentane diisocyanate; (8) Bis(2,2...Tris-l-(2-methyl)aziridinyl phosphine oxide (MAPO), bis(2-methyl aziridinyl) 2-(2-hydroxypropanoxy) propylamino phosphine oxide (BOBBA 8), and...other MAPO derivatives; (22) Bis(2-methyl aziridinyl) methylamino phosphine oxide (methyl BAPO); (23) Organo-metallic coupling agents, specifi

  20. Quantitative Determination of Compound Classes in Jet Turbine Fuels by High Performance Liquid Chromatography/Differential Refractive Index Detection. Part 2.

    DTIC Science & Technology

    1984-12-31

    Code) Washington, DC 20375-5000 8a AEO UDN POSRN FIESMO 9. PROCUREMENT INSTRUMENT IDENTIFICATION NUMBER ORGANIZATION (if aplicable ) Naa i ~ Proulion...pentane mobile phase was maintained at a flow rate of 6.0 ml/min with a Milton Roy Constametric pump operating in the 400-600 psi range. The injector was

  1. Role of NSO compounds during primary cracking of a Type II kerogen and a Type III lignite

    USGS Publications Warehouse

    Behar, F.; Lorant, F.; Lewan, M.

    2008-01-01

    The aim of this work is to follow the generation of NSO compounds during the artificial maturation of an immature Type II kerogen and a Type III lignite in order to determine the different sources of the petroleum potential during primary cracking. Experiments were carried out in closed system pyrolysis in the temperature range from 225 to 350 ??C. Two types of NSOs were recovered: one is soluble in n-pentane and the second in dichloromethane. A kinetic scheme was optimised including both kerogen and NSO cracking. It was validated by complementary experiments carried out on isolated asphaltenes generated from the Type II kerogen and on the total n-pentane and DCM extracts generated from the Type III lignite. Results show that kerogen and lignite first decompose into DCM NSOs with minor generation of hydrocarbons. Then, the main source of petroleum potential originates from secondary cracking of both DCM and n-pentane NSOs through successive decomposition reactions. These results confirm the model proposed by Tissot [Tissot, B., 1969. Premie??res donne??es sur les me??canismes et la cine??tique de la formation du pe??trole dans les bassins se??dimentaires. Simulation d'un sche??ma re??actionnel sur ordinateur. Oil and Gas Science and Technology 24, 470-501] in which the main source of hydrocarbons is not the insoluble organic matter, but the NSO fraction. As secondary cracking of the NSOs largely overlaps that of the kerogen, it was demonstrated that bulk kinetics in open system is a result of both kerogen and NSO cracking. Thus, another kinetic scheme for primary cracking in open system was built as a combination of kerogen and NSO cracking. This new kinetic scheme accounts for both the rate and amounts of hydrocarbons generated in a closed pyrolysis system. Thus, the concept of successive steps for hydrocarbon generation is valid for the two types of pyrolysis system and, for the first time, a common kinetic scheme is available for extrapolating results to natural case studies. ?? 2007 Elsevier Ltd. All rights reserved.

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

    PubMed

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

    2017-01-17

    Synthetic chemistry remains a time- and labor-intensive process of inherent hazardous nature. Our organic solvent disintegrating tablet (O-Tab) technology has shown potential to make industrial/synthetic chemistry more efficient. As is the case with pharmaceutical tablets, our reagent-containing O-Tabs are mechanically strong, but disintegrate rapidly when in contact with reaction media (organic solvents). For O-Tabs containing sensitive chemicals, they can be further coated to insulate them from air and moisture. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. [Application of metal ions and their complexes in medicine II. Application of platina complexes in the treatment of tumor].

    PubMed

    Nagy, László; Csintalan, Gabriella; Kálmán, Eszter; Nagy, Eniko; Sipos, Pál

    2004-01-01

    The rapid development of inorganic medical chemistry opens enormous potential for various applications of a range of inorganic substances in the medicine. Thus inorganic chemistry offers real possibilities to pharmaceutical industries, which used to be dominated by organic chemistry alone. The field has particularly been stimulated by the success-story of cisplatin, which is the World's best selling anticancer drug. Nowadays orally administered Pt(IV) complexes with reduced toxicity, and activity against resistant tumors are on various phases of clinical trial.

  4. Research on the development of green chemistry technology assessment techniques: a material reutilization case.

    PubMed

    Hong, Seokpyo; Ahn, Kilsoo; Kim, Sungjune; Gong, Sungyong

    2015-01-01

    This study presents a methodology that enables a quantitative assessment of green chemistry technologies. The study carries out a quantitative evaluation of a particular case of material reutilization by calculating the level of "greenness" i.e., the level of compliance with the principles of green chemistry that was achieved by implementing a green chemistry technology. The results indicate that the greenness level was enhanced by 42% compared to the pre-improvement level, thus demonstrating the economic feasibility of green chemistry. The assessment technique established in this study will serve as a useful reference for setting the direction of industry-level and government-level technological R&D and for evaluating newly developed technologies, which can greatly contribute toward gaining a competitive advantage in the global market.

  5. Using Structured Chemistry Examinations (SCHemEs) as an Assessment Method to Improve Undergraduate Students' Generic, Practical, and Laboratory-Based Skills

    ERIC Educational Resources Information Center

    Kirton, Stewart B.; Al-Ahmad, Abdullah; Fergus, Suzanne

    2014-01-01

    Increase in tuition fees means there will be renewed pressure on universities to provide "value for money" courses that provide extensive training in both subject-specific and generic skills. For graduates of chemistry this includes embedding the generic, practical, and laboratory-based skills associated with industrial research as an…

  6. OXIDATION OF ALKANES WITH AIR USING IRON AND MANGANESE CATALYSTS. AN OVERALL GREEN CHEMISTRY APPROACH INCLUDING THE USE OF ALTERNATIVE SOLVENT SYSTEMS GENERATED BY PARIS II

    EPA Science Inventory

    The selective oxidation of alkanes is an industrially important process that is often plagued by low conversions and the formation of unwanted by-products. Research being conducted at the USEPA, implements a Green chemistry approach which is utilized to improve these difficult o...

  7. Hydrogen ion input to the Hubbard Brook Experimental Forest, New Hampshire, during the last decade

    Treesearch

    Gene E. Likens; F. Herbert Bormann; John S. Eaton; Robert S. Pierce; Noye M. Johnson

    1976-01-01

    Being downwind of eastern and midwestern industrial centers, the Hubbard Brook Experimental Forest offers a prime location to monitor long-term trends in atmospheric chemistry. Continuous measurements of precipitation chemistry during the last 10 years provide a measure of recent changes in precipitation inputs of hydrogen ion. The weighted average pH of precipitation...

  8. Green and Bio-Based Solvents.

    PubMed

    Calvo-Flores, Francisco G; Monteagudo-Arrebola, María José; Dobado, José A; Isac-García, Joaquín

    2018-04-24

    Chemical reactions and many of the procedures of separation and purification employed in industry, research or chemistry teaching utilize solvents massively. In the last decades, with the birth of Green Chemistry, concerns about the employment of solvents and the effects on human health, as well as its environmental impacts and its dependence on non-renewable raw materials for manufacturing most of them, has drawn the attention of the scientific community. In this work, we review the concept of green solvent and the properties and characteristics to be considered green. Additionally, we discuss the different possible routes to prepare many solvents from biomass, as an alternative way to those methods currently applied in the petrochemical industry.

  9. Students' perceptions of academic dishonesty in the chemistry classroom laboratory

    NASA Astrophysics Data System (ADS)

    del Carlo, Dawn I.; Bodner, George M.

    2004-01-01

    Although the literature on both academic dishonesty and scientific misconduct is extensive, research on academic dishonesty has focused on quizzes, exams, and papers, with the virtual exclusion of the classroom laboratory. This study examined the distinctions undergraduate chemistry majors made between academic dishonesty in the classroom laboratory and scientific misconduct in the research laboratory. Across the spectrum of undergraduate chemistry courses, from the introductory course for first-semester chemistry majors to the capstone course in instrumental analysis, we noted that students believe the classroom lab is fundamentally different from a research or industrial lab. This difference is so significant that it carries over into students' perceptions of dishonesty in these two environments.

  10. Reducing isozyme competition increases target fatty acid accumulation in seed triacylglycerols of transgenic Arabidopsis

    USDA-ARS?s Scientific Manuscript database

    One goal of green chemistry is the production of industrially useful fatty acids (FAs) in crop plants. We focus on the engineering of industrial FAs, specifically hydroxy fatty acids (HFA) and conjugated polyenoic fatty acids (a-eleostearic acid, ESA), using Arabidopsis (Arabidopsis thaliana) as a m...

  11. Hydration of Acetylene: A 125th Anniversary

    ERIC Educational Resources Information Center

    Ponomarev, Dmitry A.; Shevchenko, Sergey M.

    2007-01-01

    The year 2006 is the 125th anniversary of a chemical reaction, the discovery of which by Mikhail Kucherov had a profound effect on the development of industrial chemistry in the 19-20th centuries. This was the hydration of alkynes catalyzed by mercury ions that made possible industrial production of acetaldehyde from acetylene. Historical…

  12. USSR Report, Energy.

    DTIC Science & Technology

    1983-06-03

    Agriculture Construction and Related Industries Consumer Goods and Domestic Trade Economic Affairs Energy Human Resources International Economic...Relations Transportation Physics and Mathmetics Space Space Biology and Aerospace Medicine Military Affairs Chemistry Cybernetics, Computers...tons of "black , it is necessary to mention the n enormous contribution to the atar ASSR’s oil industry. The iation /Tatar ASSR Production

  13. Are We Serious about Preparing Chemists for the 21st Century Workplace or Are We Just Teaching Chemistry?

    NASA Astrophysics Data System (ADS)

    Kerr, Sylvia; Runquist, Olaf

    2005-02-01

    What characteristics of employees do you value in the workplace? Sixteen leaders from world-class chemistry-based industries responded: "We want competent scientists who have high-level communication skills, cultural competencies, knowledge of how for-profit organizations function, excellent team problem-solving skills, broad backgrounds, strong work ethics, the ability to move effortlessly from science to business to humanitarian issues, and data-analysis skills." A wish list of 16 valued characteristics was generated. In response to the concern of industrial leaders and as a result of a National Science Foundation grant the Hamline University 3M Project was initiated. This unique project brought 3M professionals and Hamline University faculty members together in teams to address the concerns of industry leaders and to design and initiate curricular changes to better prepare students for the 21st century technological workplace. Each of five teams focused on one of five skill areas: namely, communications, team problem solving, data analysis, cultural competency, business, and economics. The Hamline 3M Project demonstrated a model for utilizing the industrial intellectual community to enhance undergraduate science education.

  14. Saccharin Derivative Synthesis via [1,3] Thermal Sigmatropic Rearrangement: A Multistep Organic Chemistry Experiment for Undergraduate Students

    ERIC Educational Resources Information Center

    Fonseca, Custódia S. C.

    2016-01-01

    Saccharin (1,2-benzisothiazole-3-one 1,1-dioxide) is an artificial sweetener used in the food industry. It is a cheap and easily available organic compound that may be used in organic chemistry laboratory classes for the synthesis of related heterocyclic compounds and as a derivatizing agent. In this work, saccharin is used as a starting material…

  15. The IUPAC International Congresses of Pesticide Chemistry (1963-2014) and Pest Management Science: a half-century of progress.

    PubMed

    Brooks, Gerald T

    2014-08-01

    As we approach the 2014 San Francisco IUPAC Pesticide Chemistry Congress, we reflect on the 51 years of such congresses every 4 years since 1963. Meanwhile, our journal, Pesticide Science/Pest Management Science, has in parallel continually published relevant science for nearly as long (44 years from 1970). © 2014 Society of Chemical Industry.

  16. Polymeric and Inorganic Fibers

    NASA Astrophysics Data System (ADS)

    This series presents critical reviews of the present and future trends in polymer and biopolymer science including chemistry, physical chemistry, physics and materials science. It is addressed to all scientists at universities and in industry who wish to keep abreast of advances in the topics covered. Impact Factor Ranking: Always number one in Polymer Science. More information as well as the electronic version of the whole content available at: www.springerlink.

  17. Analytical Chemistry in Russia.

    PubMed

    Zolotov, Yuri

    2016-09-06

    Research in Russian analytical chemistry (AC) is carried out on a significant scale, and the analytical service solves practical tasks of geological survey, environmental protection, medicine, industry, agriculture, etc. The education system trains highly skilled professionals in AC. The development and especially manufacturing of analytical instruments should be improved; in spite of this, there are several good domestic instruments and other satisfy some requirements. Russian AC has rather good historical roots.

  18. [1,3-Bis(diphenyl­phosphino)pentane-κ2 P,P′]tetra­carbonyl­chromium(0)

    PubMed Central

    Shawkataly, Omar bin; Thangadurai, Daniel T.; Pankhi, Mohd. Aslam A.; Shahinoor Dulal Islam, S. M.; Fun, Hoong-Kun

    2009-01-01

    In the title compound, [Cr(C29H30P2)(CO)4], the Cr atom is octa­hedrally coordinated by four carbonyl ligands and one bidentate phosphine ligand, which is bounded as a chelate in a cis position. The average Cr—P and Cr—C bond lengths are 2.377 and 1.865 Å, respectively. PMID:21582044

  19. Fluoroalkyl containing salts combined with fluorinated solvents for electrolytes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tikhonov, Konstantin; Yip, Ka Ki; Lin, Tzu-Yuan

    Provided are electrochemical cells and electrolytes used to build such cells. An electrolyte may include a fluoroalkyl-substituted LiPF.sub.6 salt or a fluoroalkyl-substituted LiBF.sub.4 salt. In some embodiments, at least one fluorinated alkyl of the salt has a chain length of from 1 to 8 or, more specifically, between about 2 and 8. These fluorinated alkyl groups, in particular, relatively large fluorinated alkyl groups improve solubility of these salts in fluorinated solvents that are less flammable than, for example, conventional carbonate solvents. At the same time, the size of fluoroalkyl-substituted salts should be limited to ensure adequate concentration of the saltmore » in an electrolyte and low viscosity of the electrolyte. In some embodiments, the concentration of a fluoroalkyl-substituted salt is at least about 0.5M. Examples of fluorinated solvents include various fluorinated esters, fluorinated ethers, and fluorinated carbonates, such a 1-methoxyheptafluoropropane, methyl nonafluorobutyl ether, ethyl nonafluorobutyl ether, 1,1,1,2,2,3,4,5,5,5-decafluoro-3-methoxy-4-(trifluoromethyl)-pentane, 3-ethoxy-1,1,1,2,3,4,4,5,5,6,6,6-dodecafluoro-2-trifluoromethyl-hexane, and 1,1,1,2,3,3-hexafluoro-4-(1,1,2,3,3,3-hexafluoropropoxy)-pentane.« less

  20. Atmospheric Mercury in the Barnett Shale Area, Texas: Implications for Emissions from Oil and Gas Processing.

    PubMed

    Lan, Xin; Talbot, Robert; Laine, Patrick; Torres, Azucena; Lefer, Barry; Flynn, James

    2015-09-01

    Atmospheric mercury emissions in the Barnett Shale area were studied by employing both stationary measurements and mobile laboratory surveys. Stationary measurements near the Engle Mountain Lake showed that the median mixing ratio of total gaseous mercury (THg) was 138 ppqv (140 ± 29 ppqv for mean ± S.D.) during the June 2011 study period. A distinct diurnal variation pattern was observed in which the highest THg levels appeared near midnight, followed by a monotonic decrease until midafternoon. The influence of oil and gas (ONG) emissions was substantial in this area, as inferred from the i-pentane/n-pentane ratio (1.17). However, few THg plumes were captured by our mobile laboratory during a ∼3700 km survey with detailed downwind measurements from 50 ONG facilities. One compressor station and one natural gas condensate processing facility were found to have significant THg emissions, with maximum THg levels of 963 and 392 ppqv, respectively, and the emissions rates were estimated to be 7.9 kg/yr and 0.3 kg/yr, respectively. Our results suggest that the majority of ONG facilities in this area are not significant sources of THg; however, it is highly likely that a small number of these facilities contribute a relatively large amount of emissions in the ONG sector.

  1. Self-assembly of a thin highly reduced graphene oxide film and its high electrocatalytic activity

    NASA Astrophysics Data System (ADS)

    Bai, Yan-Feng; Zhang, Yong-Fang; Zhou, An-Wei; Li, Hai-Wai; Zhang, Yu; Luong, John H. T.; Cui, Hui-Fang

    2014-10-01

    A thin highly reduced graphene oxide (rGO) film was self-assembled at the dimethyl formamide (DMF)-air interface through evaporation-induced water-assisted thin film formation at the pentane-DMF interface, followed by complete evaporation of pentane. The thin film was transferred onto various solid substrates for film characterization and electrochemical sensing. UV-visible spectrometry, scanning electron microscopy (SEM), atomic force microscopy (AFM) and electrochemistry techniques were used to characterize the film. An rGO film showing 82.8% of the transmittance at 550 nm corresponds to a few layers of rGO nanosheets. The rGO nanosheets cross-stack with each other, lying approximately in the plane of the film. An rGO film collected on a glassy carbon (GC) electrode exhibited improved electrical conductivity compared to GC, with the electrode charge-transfer resistance (Rct) reduced from 31 Ω to 22 Ω. The as-formed rGO/GC electrode was mechanically very stable, exhibiting significantly enhanced electrocatalytic activity to H2O2 and dopamine. Multiple layers of the rGO films on the GC electrode showed even stronger electrocatalytic activity to dopamine than that of the single rGO film layer. The controllable formation of a stable rGO film on various solid substrates has potential applications for nanoelectronics and sensors/biosensors.

  2. Development of a Small, Inexpensive, and Field-deployable Gas Chromatograph for the Automated Collection, Separation, and Analysis of Gas-phase Organic Compounds

    NASA Astrophysics Data System (ADS)

    Skog, K.; Xiong, F.; Gentner, D. R.

    2017-12-01

    The identification and quantification of gas-phase organic compounds, like volatile organic compounds (VOCs), in the atmosphere relies on separation of complex mixtures and sensitive detection. Gas chromatography (GC) is widely applied, but relies on the need for high-purity compressed gases for separation and, often for detection. We have developed a low-cost, compact GC-based system for the collection and quantitative chemical speciation of complex mixtures of common atmospheric VOCs without the need for compressed high-purity gases or expensive detectors. We present results of lab and field testing against a commercially-available GC system. At optimized linear velocities challenging VOC pairs of similar volatility were resolved within 30 minutes, including n- and i-pentane; n-pentane and isoprene; and ethylbenzene and m/p-xylene. For 5-30 minute samples, we observe ppt-level detection limits for common VOCs such as benzene, toluene, ethylbenzene, xylenes, alpha-pinene, and limonene. We also present results of in-field use for VOC measurements. In all, this instrument is accurate, precise, small, and inexpensive (<$2500). Its lack of compressed gas cylinders make it ideal for field deployment and has been demonstrated to produce similar quality data to available GC technology.

  3. Modular and selective biosynthesis of gasoline-range alkanes.

    PubMed

    Sheppard, Micah J; Kunjapur, Aditya M; Prather, Kristala L J

    2016-01-01

    Typical renewable liquid fuel alternatives to gasoline are not entirely compatible with current infrastructure. We have engineered Escherichia coli to selectively produce alkanes found in gasoline (propane, butane, pentane, heptane, and nonane) from renewable substrates such as glucose or glycerol. Our modular pathway framework achieves carbon-chain extension by two different mechanisms. A fatty acid synthesis route is used to generate longer chains heptane and nonane, while a more energy efficient alternative, reverse-β-oxidation, is used for synthesis of propane, butane, and pentane. We demonstrate that both upstream (thiolase) and intermediate (thioesterase) reactions can act as control points for chain-length specificity. Specific free fatty acids are subsequently converted to alkanes using a broad-specificity carboxylic acid reductase and a cyanobacterial aldehyde decarbonylase (AD). The selectivity obtained by different module pairings provides a foundation for tuning alkane product distribution for desired fuel properties. Alternate ADs that have greater activity on shorter substrates improve observed alkane titer. However, even in an engineered host strain that significantly reduces endogenous conversion of aldehyde intermediates to alcohol byproducts, AD activity is observed to be limiting for all chain lengths. Given these insights, we discuss guiding principles for pathway selection and potential opportunities for pathway improvement. Copyright © 2015 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  4. Cement manufacture and the environment - Part I: Chemistry and technology

    USGS Publications Warehouse

    Van Oss, H. G.; Padovani, A.C.

    2002-01-01

    Hydraulic (chiefly portland) cement is the binding agent in concrete and mortar and thus a key component of a country's construction sector. Concrete is arguably the most abundant of all manufactured solid materials. Portland cement is made primarily from finely ground clinker, which itself is composed dominantly of hydraulically active calcium silicate minerals formed through high-temperature burning of limestone and other materials in a kiln. This process requires approximately 1.7 tons of raw materials perton of clinker produced and yields about 1 ton of carbon dioxide (CO2) emissions, of which calcination of limestone and the combustion of fuels each contribute about half. The overall level of CO2 output makes the cement industry one of the top two manufacturing industry sources of greenhouse gases; however, in many countries, the cement industry's contribution is a small fraction of that from fossil fuel combustion by power plants and motor vehicles. The nature of clinker and the enormous heat requirements of its manufacture allow the cement industry to consume a wide variety of waste raw materials and fuels, thus providing the opportunity to apply key concepts of industrial ecology, most notably the closing of loops through the use of by-products of other industries (industrial symbiosis). In this article, the chemistry and technology of cement manufacture are summarized. In a forthcoming companion article (part II), some of the environmental challenges and opportunities facing the cement industry are described. Because of the size and scope of the U.S. cement industry, the analysis relies primarily on data and practices from the United States.

  5. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Green, D.W.; Heinrich, R.R.; Graczyk, D.G.

    The purpose of this report is to summarize the activities of the Analytical Chemistry Laboratory (ACL) at Argonne National Laboratory (ANL) for Fiscal Year 1991 (October 1990 through September 1991). This is the eighth annual report for the ACL. The Analytical Chemistry Laboratory is a full-cost-recovery service center, with the primary mission of providing a broad range of analytical chemistry support services to the scientific and engineering programs at ANL. In addition, the ACL conducts a research program in analytical chemistry, works on instrumental and methods development, and provides analytical services for governmental, educational, and industrial organizations. The ACL handlesmore » a wide range of analytical problems, from routine standard analyses to unique problems that require significant development of methods and techniques.« less

  6. Hybrid carrageenans: isolation, chemical structure, and gel properties.

    PubMed

    Hilliou, Loic

    2014-01-01

    Hybrid carrageenan is a special class of carrageenan with niche application in food industry. This polysaccharide is extracted from specific species of seaweeds belonging to the Gigartinales order. This chapter focuses on hybrid carrageenan showing the ability to form gels in water, which is known in the food industry as weak kappa or kappa-2 carrageenan. After introducing the general chemical structure defining hybrid carrageenan, the isolation of the polysaccharide will be discussed focusing on the interplay between seaweed species, extraction parameters, and the hybrid carrageenan chemistry. Then, the rheological experiments used to determine the small and large deformation behavior of gels will be detailed before reviewing the relationships between gel properties and hybrid carrageenan chemistry. © 2014 Elsevier Inc. All rights reserved.

  7. Study on Sources of Volatile Organic Compounds (CMB) in Pearl River Delta region, China

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Shao, M.; Lu, S.; Chang, C.; Wang, C. J.; Wang, B.

    2007-05-01

    The profiles of major Volatile organic compounds (VOCs) sources including vehicle exhaust, gasoline vapor, painting, asphalt, liquefied petroleum gas (LPG), biomass burning and petrochemical industry in Pearl River Delta were experimentally determined. Source samples were taken by using dilution chamber for mobile and stationary sources, laboratory simulation for biomass burning. The concentrations of 108 VOC species of sources were quantified by using canister with pre-concentration-GC/MS system, from which 52 PAMS hydrocarbons and one kind of chlorinated hydrocarbon were deployed to build the source profiles for source apportionment of VOCs. Based the measurement of source profiles, the possible tracers for various emission sources were identified, e.g 2-methylbutane and 1,3-butadiene were the tracers for motor vehicle exhaust, the characteristic compounds of architectural and furnishing coatings are aromatics such as toluene and m/p-xylene; the light hydrocarbons, namely n-butane, trans-2-butene and n-pentane, dominated the composition of gasoline vapor; and the nonane, decane and undecane are found to represent the asphalt emissions etc.. The CMB receptor model was applied to source apportionment of 58 hydrocarbons measured at seven sites during the PRD campaign, 2004. The 12 kinds of VOC sources include gasoline/diesel-powered vehicle exhaust, gasoline/diesel headspace vapor, vehicle evaporative emissions, liquid petroleum gas (LPG) leakage, painting vapors, asphalt emission from paved road, biomass burning, coal burning, chemical industry and petroleum refinery. Vehicle exhaust was the largest sources contributing over half of the ambient VOCs at the three urban sites (GuangZhou, FoShan and ZhongShan). LPG leakage played an important role with the percentage of 8- 16% in most sites in PRD. Contributions from solvents usage were highest at DongGuan, an industrial site. At XinKen, the solvents and coatings had the largest percentage of 31% probably due to the influence of its upwind area of DongGuan. The local biomass burning was also found to be a noticeable source at XK.

  8. Sensitive detection of n-alkanes using a mixed ionization mode proton-transfer-reaction mass spectrometer

    NASA Astrophysics Data System (ADS)

    Amador-Muñoz, Omar; Misztal, Pawel K.; Weber, Robin; Worton, David R.; Zhang, Haofei; Drozd, Greg; Goldstein, Allen H.

    2016-11-01

    Proton-transfer-reaction mass spectrometry (PTR-MS) is a technique that is widely used to detect volatile organic compounds (VOCs) with proton affinities higher than water. However, n-alkanes generally have a lower proton affinity than water and therefore proton transfer (PT) by reaction with H3O+ is not an effective mechanism for their detection. In this study, we developed a method using a conventional PTR-MS to detect n-alkanes by optimizing ion source and drift tube conditions to vary the relative amounts of different primary ions (H3O+, O2+, NO+) in the reaction chamber (drift tube). There are very few studies on O2+ detection of alkanes and the mixed mode has never been proposed before. We determined the optimum conditions and the resulting reaction mechanisms, allowing detection of n-alkanes from n-pentane to n-tridecane. These compounds are mostly emitted by evaporative/combustion process from fossil fuel use. The charge transfer (CT) mechanism observed with O2+ was the main reaction channel for n-heptane and longer n-alkanes, while for n-pentane and n-hexane the main reaction channel was hydride abstraction (HA). Maximum sensitivities were obtained at low E / N ratios (83 Td), low water flow (2 sccm) and high O2+ / NO+ ratios (Uso = 180 V). Isotopic 13C contribution was taken into account by subtracting fractions of the preceding 12C ion signal based on the number of carbon atoms and the natural abundance of 13C (i.e., 5.6 % for n-pentane and 14.5 % for n-tridecane). After accounting for isotopic distributions, we found that PT cannot be observed for n-alkanes smaller than n-decane. Instead, protonated water clusters of n-alkanes (M ṡ H3O+) species were observed with higher abundance using lower O2+ and higher water cluster fractions. M ṡ H3O+ species are probably the source for the M + H+ species observed from n-decane to n-tridecane. Normalized sensitivities to O2+ or to the sum of O2++ NO+ were determined to be a good metric with which to compare sensitivities for n-alkane detection between experiments. Double hydride abstraction was observed from the reaction with O2+. Sensitivity to CT increased with carbon chain length from n-pentane to n-dodecane, sensitivity to HA increased from n-heptane to n-dodecane and sensitivity to PT increased from n-decane to n-tridecane. Sensitivity to CT exponentially decreased with molecular ionization energy, which is inversely related to the carbon chain length. We introduce a calibrated fragmentation algorithm as a method to determine the concentrations of n-alkanes and demonstrate its effectiveness using a custom n-alkane mixture and a much more complex oil example representing perhaps the most difficult mixture available for application of the method. We define optimum conditions for using the mixed ionization mode to measure n-alkanes in conventional PTR-MS instruments regardless of whether they are equipped with switchable reagent ion (SRI) capabilities.

  9. Revitalizing chemistry laboratory instruction

    NASA Astrophysics Data System (ADS)

    McBride, Phil Blake

    This dissertation involves research in three major domains of chemical education as partial fulfillment of the requirements for the Ph.D. program in chemistry at Miami University with a major emphasis on chemical education, and concurrent study in organic chemistry. Unit I, Development and Assessment of a Column Chromatography Laboratory Activity, addresses the domain of Instructional Materials Development and Testing. This unit outlines the process of developing a publishable laboratory activity, testing and revising that activity, and subsequently sharing that activity with the chemical education community. A laboratory activity focusing on the separation of methylene blue and sodium fluorescein was developed to demonstrate the effects of both the stationary and mobile phase in conducting a separation. Unit II, Bringing Industry to the Laboratory, addresses the domain of Curriculum Development and Testing. This unit outlines the development of the Chemistry of Copper Mining module, which is intended for use in high school or undergraduate college chemistry. The module uses the learning cycle approach to present the chemistry of the industrial processes of mining copper to the students. The module includes thirteen investigations (three of which are web-based and ten which are laboratory experiments) and an accompanying interactive CD-ROM, which provides an explanation of the chemistry used in copper mining with a virtual tour of an operational copper mine. Unit III, An Alternative Method of Teaching Chemistry. Integrating Lecture and the Laboratory, is a project that addresses the domain of Research in Student Learning. Fundamental Chemistry was taught at Eastern Arizona College as an integrated lecture/laboratory course that met in two-hour blocks on Monday, Wednesday, and Friday. The students taking this integrated course were compared with students taking the traditional 1-hour lectures held on Monday, Wednesday, and Friday, with accompanying 3-hour lab on Tuesday or Thursday. There were 119 students in the test group, 522 students in the Shelton control group and 556 students in the McBride control group. Both qualitative data and quantitative data were collected. A t-test was used to test significance.

  10. Enabling Chemistry Technologies and Parallel Synthesis-Accelerators of Drug Discovery Programmes.

    PubMed

    Vasudevan, A; Bogdan, A R; Koolman, H F; Wang, Y; Djuric, S W

    There is a pressing need to improve overall productivity in the pharmaceutical industry. Judicious investments in chemistry technologies can have a significant impact on cycle times, cost of goods and probability of technical success. This perspective describes some of these technologies developed and implemented at AbbVie, and their applications to the synthesis of novel scaffolds and to parallel synthesis. © 2017 Elsevier B.V. All rights reserved.

  11. Heterocyclic chemistry in crop protection.

    PubMed

    Lamberth, Clemens

    2013-10-01

    An overview is given of the significance of heterocycles in crop protection chemistry, which is enormous as more than two-thirds of all agrochemicals launched to the market within the last 20 years belong to this huge group of chemicals. This review focuses on two important aspects of heterocyclic agrochemistry: the different roles of heterocyclic scaffolds in crop protection agents and the major possibilities for their synthesis. © 2013 Society of Chemical Industry.

  12. Eco-Driven Chemical Research in the Boundary between Academia and Industry

    ERIC Educational Resources Information Center

    Sjöström, Jesper

    2013-01-01

    This paper examines and discusses the views on science and society held among PhD students working in two different industrially and environmentally driven research programmes in the broad area of green chemistry. It is based on thirteen in-depth interviews. The analysis shows three main ways of handling the situation as "post-academic"…

  13. Modeling the atmospheric chemistry of TICs

    NASA Astrophysics Data System (ADS)

    Henley, Michael V.; Burns, Douglas S.; Chynwat, Veeradej; Moore, William; Plitz, Angela; Rottmann, Shawn; Hearn, John

    2009-05-01

    An atmospheric chemistry model that describes the behavior and disposition of environmentally hazardous compounds discharged into the atmosphere was coupled with the transport and diffusion model, SCIPUFF. The atmospheric chemistry model was developed by reducing a detailed atmospheric chemistry mechanism to a simple empirical effective degradation rate term (keff) that is a function of important meteorological parameters such as solar flux, temperature, and cloud cover. Empirically derived keff functions that describe the degradation of target toxic industrial chemicals (TICs) were derived by statistically analyzing data generated from the detailed chemistry mechanism run over a wide range of (typical) atmospheric conditions. To assess and identify areas to improve the developed atmospheric chemistry model, sensitivity and uncertainty analyses were performed to (1) quantify the sensitivity of the model output (TIC concentrations) with respect to changes in the input parameters and (2) improve, where necessary, the quality of the input data based on sensitivity results. The model predictions were evaluated against experimental data. Chamber data were used to remove the complexities of dispersion in the atmosphere.

  14. Moving Green Chemistry Forward: Networks as a Foundation

    NASA Astrophysics Data System (ADS)

    Carter, T.; Lough, G.

    2014-12-01

    Green chemistry is a growing discipline, but for a variety of reasons, it has not yet become integrated into science curriculum and the greater societal conscience. With its increasing economic benefits to many sectors including business, industry, and academia and its potential to make science more accessible not only to science students but also to the general citizenry, we suggested answers to the questions: Why has greater success not been realized? What are the particular barriers to wider implementation? And what are incentives and ways to move green chemistry forward? We suggest some strategies and options to both increase the use of green chemistry principles and to also increase stakeholders' understanding of the importance and utility of green chemistry in their daily lives. For example, our main suggestions are that an inclusive, multidisciplinary network would aid in coordinating data and in translating the science into user friendly tools, and that an educational component embedded in this greater effort would also serve to move green chemistry forward.

  15. Reconstructing Early Industrial Contributions to Legacy Trace Metal Contamination in Southwestern Pennsylvania

    NASA Astrophysics Data System (ADS)

    Rossi, R.; Bain, D.; Hillman, A. L.; Pompeani, D. P.; Abbott, M. B.

    2015-12-01

    The remobilization of legacy contamination stored in floodplain sediments remains a threat to ecosystem and human health, particularly with potential changes in global precipitation patterns and flooding regimes. Vehicular and industrial emissions are often the dominant, recognized source of anthropogenic trace metal loadings to ecosystems today. However, loadings from early industrial activities are poorly characterized and potential sources of trace metal inputs. While potential trace metal contamination from these activities is recognized (e.g., the historical use of lead arsenate as a pesticide), the magnitude and distribution of legacy contamination is often unknown. This presentation reconstructs a lake sediment record of trace metal inputs from an oxbow lake in Southwestern Pennsylvania. Sediment cores were analyzed for major and trace metal chemistry, carbon to nitrogen ratios, bulk density, and magnetic susceptibility. Sediment trace metal chemistry in this approximately 250 year record (180 cm) record changes in land use and industry both in the 19th century and the 20th century. Of particular interest is early 19th century loadings of arsenic and calcium to the lake, likely attributable to pesticides and lime used in tanning processes near the lake. After this period of tanning dominated inputs, sediment barium concentrations rise, likely reflecting the onset of coal mining operations and resulting discharge of acid mine drainage to surface waters. In the 20th century portion of our record (70 -20 cm), patterns in sediment zinc, cadmium, and lead concentrations are dominated by the opening and closing of the nearby Donora Zinc Works and the American Steel & Wire Works, infamous facilities in the history of air quality regulation. The most recent sediment chemistry records periods include the enactment of air pollution legislation (~ 35 cm), and the phase out of tetraethyl leaded gasoline (~30 cm). Our study documents the impact of early industry in the Southwestern Pennsylvania region, as well as early industrial coal production/consumption on legacy trace metal contamination. This record suggests that some early industrial processes can rival more recent metal fluxes and should be carefully considered in modern assessments of legacy sediment metal contamination.

  16. Modeling local chemistry in PWR steam generator crevices

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Millett, P.J.

    1997-02-01

    Over the past two decades steam generator corrosion damage has been a major cost impact to PWR owners. Crevices and occluded regions create thermal-hydraulic conditions where aggressive impurities can become highly concentrated, promoting localized corrosion of the tubing and support structure materials. The type of corrosion varies depending on the local conditions, with stress corrosion cracking being the phenomenon of most current concern. A major goal of the EPRI research in this area has been to develop models of the concentration process and resulting crevice chemistry conditions. These models may then be used to predict crevice chemistry based on knowledgemore » of bulk chemistry, thereby allowing the operator to control corrosion damage. Rigorous deterministic models have not yet been developed; however, empirical approaches have shown promise and are reflected in current versions of the industry-developed secondary water chemistry guidelines.« less

  17. Biomass Deconstruction and Pretreatment Publications | Bioenergy | NREL

    Science.gov Websites

    a quantitative indication of data uncertainty. Enlarge image Transgenic Ferritin Overproduction Pretreatment, Industrial & Engineering Chemistry Research Image of a chart showing solubilization of

  18. Method for the synthesis of chlorosilanes

    DOEpatents

    Wheeler, D.R.; Pollagi, T.P.

    1999-08-17

    A novel method is described for the synthesis of chlorinated or partially chlorinated organosilanes and organopolysilanes. The chlorination is effected by contacting an organosilanes or organopolysilanes with anhydrous CuCl{sub 2} in a nonpolar alkane solvent, preferably pentane or hexadecane, without the use of a catalyst. Copper metal, which is easily filtered, is a reaction product. The filtrate containing the chlorinated organosilane or organopolysilane can be used directly as a reactant to produce, for example, aminoorganosilanes.

  19. Method for the synthesis of chlorosilanes

    DOEpatents

    Wheeler, David R.; Pollagi, Timothy P.

    1999-01-01

    A novel method for the synthesis of chlorinated or partially chlorinated organosilanes and organopolysilanes. The chlorination is effected by contacting an organosilanes or organopolysilanes with anhydrous CuCl.sub.2 in a nonpolar alkane solvent, preferably pentane or hexadecane, without the use of a catalyst. Copper metal, which is easily filtered, is a reaction product. The filtrate containing the chlorinated organosilane or organopolysilane can be used directly as a reactant to produce, for example, aminoorganosilanes.

  20. Observed trends in ambient concentrations of C 2-C 8 hydrocarbons in the United Kingdom over the period from 1993 to 2004

    NASA Astrophysics Data System (ADS)

    Dollard, G. J.; Dumitrean, P.; Telling, S.; Dixon, J.; Derwent, R. G.

    Hourly measurements of up to 26 C 2-C 8 hydrocarbons have been made at eight urban background sites, three urban-industrial sites, a kerbside and a rural site in the UK from 1993 onwards up until the end of December 2004. Average annual mean benzene and 1,3-butadiene concentrations at urban background locations have declined at about -20% per year and the observed declines have exactly mimicked the inferred declines in benzene and 1,3-butadiene emissions over the same period. Ninety-day rolling mean concentrations of ethylene, propylene, n- and i-butane, n- and i-pentane, isoprene and propane at urban and rural sites have also declined steadily by between -10% and -30% per year. Rolling mean concentrations of acetylene, 2- and 3-methylpentane, n-hexane, n-heptane, cis- and trans-but-2-ene, cis- and trans-pent-2-ene, toluene, ethylbenzene and o-, m- and p-xylene at a roadside location in London have all declined at between -14% and -21% per year. These declines demonstrate that motor vehicle exhaust catalysts and evaporative canisters have effectively and efficiently controlled vehicular emissions of hydrocarbons in the UK. Urban ethane concentrations arising largely from natural gas leakage have remained largely unchanged over this same period.

  1. Molecular dynamics simulations of diffusion and clustering along critical isotherms of medium-chain n-alkanes.

    PubMed

    Mutoru, J W; Smith, W; O'Hern, C S; Firoozabadi, A

    2013-01-14

    Understanding the transport properties of molecular fluids in the critical region is important for a number of industrial and natural systems. In the literature, there are conflicting reports on the behavior of the self diffusion coefficient D(s) in the critical region of single-component molecular systems. For example, D(s) could decrease to zero, reach a maximum, or remain unchanged and finite at the critical point. Moreover, there is no molecular-scale understanding of the behavior of diffusion coefficients in molecular fluids in the critical regime. We perform extensive molecular dynamics simulations in the critical region of single-component fluids composed of medium-chain n-alkanes-n-pentane, n-decane, and n-dodecane-that interact via anisotropic united-atom potentials. For each system, we calculate D(s), and average molecular cluster sizes κ(cl) and numbers N(cl) at various cluster lifetimes τ, as a function of density ρ in the range 0.2ρ(c) ≤ ρ ≤ 2.0ρ(c) at the critical temperature T(c). We find that D(s) decreases with increasing ρ but remains finite at the critical point. Moreover, for any given τ < 1.2 × 10(-12) s, κ(cl) increases with increasing ρ but is also finite at the critical point.

  2. Robin Ganellin gives his views on medicinal chemistry and drug discovery. Interview by Stephen L. Carney.

    PubMed

    Ganellin, C Robin

    2004-02-15

    Robin Ganellin was born in East London and studied chemistry at Queen Mary College, London, receiving a PhD in 1958 under Professor Michael Dewar for his research on tropylium chemistry. He joined Smith Kline & French Laboratories (SK&F) in the UK in 1958 and was one of the co-inventors of the revolutionary drug cimetidine (Tagamet(R)) He subsequently became Vice-President for Research at the company's Welwyn facility. In 1986 he was awarded a DSc from London University for his work on the medicinal chemistry of drugs acting at histamine receptors and was also made a Fellow of the Royal Society and appointed to the SK&F Chair of Medicinal Chemistry at University College London, where he is now Emeritus Professor of Medicinal Chemistry. Professor Ganellin has been honoured extensively, including such awards as the Royal Society of Chemistry Award for Medicinal Chemistry, their Tilden Medal and Lectureship and their Adrien Albert Medal and Lectureship, Le Prix Charles Mentzer de France, the ACS Division of Medicinal Chemistry Award, the Society of Chemical Industry Messel Medal and the Society for Drug Research Award for Drug Discovery. He is a past Chairman of the Society for Drug Research, was President of the Medicinal Chemistry Section of IUPAC, and is currently Chairman of the IUPAC Subcommittee on Medicinal Chemistry and Drug Development.

  3. Want Ads, Job Skills, and Curriculum: A Survey of 1998 Chemistry Help-Wanted Ads

    NASA Astrophysics Data System (ADS)

    Headrick, Kurt L.

    2001-09-01

    Employer surveys are useful checks on how well we are preparing students for the working world. Employer surveys are also useful because they put curriculum deficiencies into terms that are readily understood; they can thus be a catalyst for curriculum reform. This study classified 2035 chemistry jobs advertized in newspapers across the USA in the fall of 1998 according to job type, employment sector, industry, type of chemistry principally involved, and academic background and experience desired. Job ads were also searched for keywords denoting a broad range of instrumentation and techniques, personality traits, and general work skills and experience. The total of 7872 keywords, an average of 3.9 per job, indicates that employers are looking for more than just a B.S. in chemistry.

  4. Interview with Future Medicinal Chemistry's US Senior Editor, Iwao Ojima. Interview by Issac Bruce.

    PubMed

    Ojima, Iwao

    2012-10-01

    Professor Iwao Ojima studied at the University of Tokyo (Japan) before being appointed as a Senior Research Fellow and Group Leader at the Sagami Institute of Chemical Research. He is now Director of the Institute of Chemical Biology and Drug Discovery at State University of New York (USA) and has been a visiting professor in European, North American and Asian academic institutions. Professor Ojima agreed to serve as the US Senior Editor of Future Medicinal Chemistry when it launched in 2009 and continues to provide his expertise to the journal. Professor Ojima spoke to Future Medicinal Chemistry about why medicinal chemistry is such an exciting field to work in, the state of the pharmaceutical industry, and what features and issues make this journal unique.

  5. 200 Years of Lithium and 100 Years of Organolithium Chemistry

    PubMed Central

    2018-01-01

    The element lithium has been discovered 200 years ago. Due to its unique properties it has emerged to play a vital role in industry, esp. for energy storage, and lithium‐based products and processes support sustainable technological developments. In addition to the many uses of lithium in its inorganic forms, lithium has a rich organometallic chemistry. The development of organometallic chemistry has been hindered by synthetic problems from the start. When Wilhelm Schlenk developed the basic principles to handle and synthesize air‐ and moisture‐sensitive compounds, the road was open to further developments. After more information was available about the stability and solubility of such compounds, they started to play an essential role in other fields of chemistry as alkyl or aryl transfer reagents. PMID:29540939

  6. Atmospheric Chemistry and Air Pollution

    DOE PAGES

    Gaffney, Jeffrey S.; Marley, Nancy A.

    2003-01-01

    Atmospheric chemistry is an important discipline for understanding air pollution and its impacts. This mini-review gives a brief history of air pollution and presents an overview of some of the basic photochemistry involved in the production of ozone and other oxidants in the atmosphere. Urban air quality issues are reviewed with a specific focus on ozone and other oxidants, primary and secondary aerosols, alternative fuels, and the potential for chlorine releases to amplify oxidant chemistry in industrial areas. Regional air pollution issues such as acid rain, long-range transport of aerosols and visibility loss, and the connections of aerosols to ozonemore » and peroxyacetyl nitrate chemistry are examined. Finally, the potential impacts of air pollutants on the global-scale radiative balances of gases and aerosols are discussed briefly.« less

  7. The Physics Teacher: The Four States of Matter—Solid, Squishy, Liquid, and Gas

    NASA Astrophysics Data System (ADS)

    Clark, Roy W.

    2007-04-01

    The featured article offers several demonstrations of substances that seem to be neither solid nor liquid, but somewhere in between. The authors suggest laboratory experiments that can be performed by beginning physics students, and suggest theoretical explanations for the strange viscosity behaviors. The subject is chemistry much more than physics, and it may require chemistry textbook authors to rethink the popular definitions of physical and chemical change. This reviewer then comments on the historical origins of squishiness, and on its unfortunate neglect, in their author's opinion, by general chemistry texts. The subject is properly called rheology, and is of considerable significance to industrial chemists.

  8. Computer-aided drug discovery research at a global contract research organization

    NASA Astrophysics Data System (ADS)

    Kitchen, Douglas B.

    2017-03-01

    Computer-aided drug discovery started at Albany Molecular Research, Inc in 1997. Over nearly 20 years the role of cheminformatics and computational chemistry has grown throughout the pharmaceutical industry and at AMRI. This paper will describe the infrastructure and roles of CADD throughout drug discovery and some of the lessons learned regarding the success of several methods. Various contributions provided by computational chemistry and cheminformatics in chemical library design, hit triage, hit-to-lead and lead optimization are discussed. Some frequently used computational chemistry techniques are described. The ways in which they may contribute to discovery projects are presented based on a few examples from recent publications.

  9. The calculation of quality indices of the water heat carrier and estimation of the condition of water chemistry of drum boilers

    NASA Astrophysics Data System (ADS)

    Larin, B. M.; Larin, A. B.; Kozyulina, E. V.; Kolegov, A. V.

    2012-07-01

    There is suggested a method for an indirect calculated identification of ionic impurities in water of drum boilers ( p b = 13.8 MPa) by means of measuring the electric conductivity of cooled samples (direct and H-cationized ones) of the feedwater and drum water. This paper reports the results of an industrial experiment carried out on the drum power boiler during the entire heating season. The possibility of evaluating the condition of the water chemistry, with plotting a phase diagram of the phosphate-based water chemistry and determining characteristic dependences, is shown.

  10. Halogenase engineering and its utility in medicinal chemistry.

    PubMed

    Fraley, Amy E; Sherman, David H

    2018-06-15

    Halogenation is commonly used in medicinal chemistry to improve the potency of pharmaceutical leads. While synthetic methods for halogenation present selectivity and reactivity challenges, halogenases have evolved over time to perform selective reactions under benign conditions. The optimization of halogenation biocatalysts has utilized enzyme evolution and structure-based engineering alongside biotransformation in a variety of systems to generate stable site-selective variants. The recent improvements in halogenase-catalyzed reactions has demonstrated the utility of these biocatalysts for industrial purposes, and their ability to achieve a broad substrate scope implies a synthetic tractability with increasing relevance in medicinal chemistry. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Computer-aided drug discovery research at a global contract research organization.

    PubMed

    Kitchen, Douglas B

    2017-03-01

    Computer-aided drug discovery started at Albany Molecular Research, Inc in 1997. Over nearly 20 years the role of cheminformatics and computational chemistry has grown throughout the pharmaceutical industry and at AMRI. This paper will describe the infrastructure and roles of CADD throughout drug discovery and some of the lessons learned regarding the success of several methods. Various contributions provided by computational chemistry and cheminformatics in chemical library design, hit triage, hit-to-lead and lead optimization are discussed. Some frequently used computational chemistry techniques are described. The ways in which they may contribute to discovery projects are presented based on a few examples from recent publications.

  12. Irrigation of an established vineyard with winery cleaning agent solution (simulated winery wastewater): vine growth, berry quality, and soil chemistry

    USDA-ARS?s Scientific Manuscript database

    The ability to use winery wastewater (WW) for irrigation purposes could be a beneficial to the wine industry. A major difficulty in studying WW use is its inconsistent availability and composition. As such, we applied four simulated WWs composed of salts from two main industrial cleaning agents, and...

  13. CHEMISTRY FOR THE SAFETY MAN. SAFETY IN INDUSTRY--ENVIRONMENTAL AND CHEMICAL HAZARDS SERVICES.

    ERIC Educational Resources Information Center

    CESTRONE, PATRICK F.

    THIS BULLETIN, ONE OF A SERIES ON SAFETY IN INDUSTRY, IS INTENDED TO PROVIDE THE BACKGROUND WHICH WILL ENABLE THE SAFETY MAN TO UNDERSTAND SOME OF THE PRINCIPLES APPLIED IN CONTROLLING CHEMICAL HAZARDS. IT WAS PREPARED IN THE OFFICE OF OCCUPATIONAL SAFETY, DIVISION OF PROGRAMING AND RESEARCH, BUREAU OF LABOR STANDARDS. TOPICS INCLUDE (1) WHAT IS…

  14. 'Click chemistry' for diagnosis: a patent review on exploitation of its emerging trends.

    PubMed

    Mandhare, Anita; Banerjee, Paromita; Bhutkar, Smita; Hirwani, Rajkumar

    2014-12-01

    Click chemistry is the novel synthetic approach towards developing reactions with large thermodynamic driving forces to give almost complete conversion of new molecular reagents to a single product. Thus, click chemistry describes the chemistry for making carbon-heteroatom-carbon bonds in benign solvents, especially in water, and having a plethora of chemical and biological applications. This has played an important role in early detection of diseases, real-time monitoring of drug delivery and investigating the biomolecular functions in vivo. This review aims at highlighting the research advancements in click chemistry published in the patent literature and categorizing the patents according to the technological progress. An extensive search was carried out to collect and analyze the patent information claiming the use of click chemistry in biotechnology, especially for diagnosis. The study further concentrates on licensing of the click chemistry patents and defining the recent breakthroughs. Different databases like Espacenet, ISI Web of Science, Patbase and Thomson Innovation are used to compile the relevant literature. In recent years, considerable development in the click concept has encouraged researchers in using click reactions in almost every branch of industry that uses chemistry. Click chemistry for chemical ligation has been immensely explored in the field of biotechnology especially for detection, diagnosis and therapeutics.

  15. Radiation curing progress in Hungary

    NASA Astrophysics Data System (ADS)

    Czvikovszky, T.

    Radiation chemistry and radiation processing is an actively cultivated field of chemical technology and of applied research in several Central/Eastern European countries. Hungary, with his synthetic polymer production over 50 kg/capita/year, with his strong commitment in nuclear power production /almost 40 % of total electric power/, with his pioneering activity in food irradiation, radiation sterilization as well as EB processing of polymer — performs an iniciating role in this region. Actually four industrial EB machines are working in Hungary on plastics converting. Two of these accelerators, manufactured in SU are producing heat-shrinkable products. Two other, low-energy EB machines from FRG are working on industrial-scale surface-coating. An ELECTROCURTAIN /USA/ is serving R/D. Some actual problems of the applied radiation chemistry of EB-curing will be discussed.

  16. Coincident Observations of Surface Ozone and NMVOCs over Abu Dhabi

    NASA Astrophysics Data System (ADS)

    Abbasi, Naveed; Majeed, Tariq; Iqbal, Mazhar; Tarasick, David; Davies, Jonathan; Riemer, Daniel; Apel, Eric

    2016-07-01

    The vertical profiles of ozone are measured coincidently with non-methane volatile organic compounds (NMVOCs) at the meteorological site located at the Abu Dhabi international airport (latitude 24.45N; longitude 54.22E) during the years 2012 - 2014. Some of the profiles show elevated surface ozone >95 ppbv during the winter months (December, January and February). The ground-level NMVOCs obtained from the gas chromatography-flame ionization detection/mass spectrometry system also show elevated values of acetylene, ethane, propane, butane, pentane, benzene, and toluene. NMVOCs and ozone abundances in other seasons are much lower than the values in winter season. NMVOCs are emitted from an extensive number of sources in urban environments including fuel production, distribution, and consumption, and serve as precursor of ozone. Transport sources contribute a substantial portion of the NMVOC burden to the urban atmosphere in developed regions. Abu Dhabi is located at the edge of the Arabian Gulf and is highly affected by emissions from petrochemical industries in the neighboring Gulf region. The preliminary results indicate that wintertime enhancement in ozone is associated with large values of NMVOCs at Abu Dhabi. The domestic production of surface ozone is estimated from the combination of oxygen recombination and NMVOCs and compared with the data. It is estimated that about 40-50% of ozone in Abu Dhabi is transported from the neighbouring petrochemical industries. We will present ozone sounding and NMVOCs data and our model estimates of surface ozone, including a discussion on the high levels of the tropospheric ozone responsible for contaminating the air quality in the UAE. This work is supported by National Research Foundation, UAE.

  17. Proceedings of Symposium Lipid Mediators in Immunology of Shock Held in Copenhagen, Denmark 21-25 July 1986

    DTIC Science & Technology

    1989-07-01

    MONITORING ORGANIZATION REPORT NUMBER(S) Ga . NAME OF PERFORMING ORGANIZATION 6b. OFFICE SYMBOL 7a. NAME OF MONITORING ORGANIZATION NATO Symposium...is a brief consideration of several new drugs which may prove to be valua- ble therapeutic agents in trauma, shock and related conditions. In...Bertrand, M. Lismonde Vol Detection of Pentane as a Measurement of Lipid Peroxidation in Humans Using Gas Chromatography With a Photoionization Detector

  18. Transition-Metal-Free Alkynylation of Aryl Chlorides

    PubMed Central

    Truong, Thanh; Daugulis, Olafs

    2011-01-01

    Two sets of conditions have been developed for a base-mediated, transition-metal-free alkynylation of aryl chlorides that proceeds via benzyne intermediates. The first set of conditions involves the use of TMPLi base in a pentane/THF mixture at 25 °C. The second set involves use of a metal alkoxide base in dioxane at elevated temperature. Reasonable functional group tolerance has been observed. Fluoro, trifluoromethyl, silyl, cyano, and alcohol functionalities are compatible with the reaction conditions. PMID:21786825

  19. Microencapsulation, Chemical Characterization, and Antimicrobial Activity of Mexican (Lippia graveolens H.B.K.) and European (Origanum vulgare L.) Oregano Essential Oils

    PubMed Central

    Regalado-González, Carlos; Vázquez-Landaverde, Pedro; Guerrero-Legarreta, Isabel; García-Almendárez, Blanca E.

    2014-01-01

    The effect of solvent polarity (methanol and pentane) on the chemical composition of hydrodistilled essential oils (EO's) of Lippia graveolens H.B.K. (MXO) and Origanum vulgare L. (EUO) was studied by GC-MS. Composition of modified starch microencapsulated EO's was conducted by headspace-solid-phase microextraction (HS-SPME). The antimicrobial activity of free and microencapsulated EO's was evaluated. They were tested against Salmonella sp., Brochothrix thermosphacta, Pseudomonas fragi, Lactobacillus plantarum, and Micrococcus luteus. Thymol and carvacrol were among the main components of EO's and their free and microencapsulated inhibitory activity was tested against M. luteus, showing an additive combined effect. Chemical composition of EO's varied according to the solvent used for GC analysis and to volatile fraction as evaluated by HS-SPME. Thymol (both solvents) was the main component in essential oil of MXO, while carvacrol was the main component of the volatile fraction. EUO showed α-pinene (methanol) and γ-terpinene (pentane) as major constituents, the latter being the main component of the volatile fraction. EO's showed good stability after 3 months storage at 4°C, where antimicrobial activity of microencapsulated EO's remained the same, while free EO's decreased 41% (MXO) and 67% (EUO) from initial activity. Microencapsulation retains most antimicrobial activity and improves stability of EO's from oregano. PMID:25177730

  20. Explosion characteristics of flammable organic vapors in nitrous oxide atmosphere.

    PubMed

    Koshiba, Yusuke; Takigawa, Tomihisa; Matsuoka, Yusaku; Ohtani, Hideo

    2010-11-15

    Despite unexpected explosion accidents caused by nitrous oxide have occurred, few systematic studies have been reported on explosion characteristics of flammable gases in nitrous oxide atmosphere compared to those in air or oxygen. The objective of this paper is to characterize explosion properties of mixtures of n-pentane, diethyl ether, diethylamine, or n-butyraldehyde with nitrous oxide and nitrogen using three parameters: explosion limit, peak explosion pressure, and time to the peak explosion pressure. Then, similar mixtures of n-pentane, diethyl ether, diethylamine, or n-butyraldehyde with oxygen and nitrogen were prepared to compare their explosion characteristics with the mixtures containing nitrous oxide. The explosion experiments were performed in a cylindrical vessel at atmospheric pressure and room temperature. The measurements showed that explosion ranges of the mixtures containing nitrous oxide were narrow compared to those of the mixtures containing oxygen. On the other hand, the maximum explosion pressures of the mixtures containing nitrous oxide were higher than those of the mixtures containing oxygen. Moreover, our experiments revealed that these mixtures differed in equivalence ratios at which the maximum explosion pressures were observed: the pressures of the mixtures containing nitrous oxide were observed at stoichiometry; in contrast, those of the mixtures containing oxygen were found at fuel-rich area. Chemical equilibrium calculations confirmed these behaviors. Copyright © 2010 Elsevier B.V. All rights reserved.

  1. Enhanced cometabolic degradation of methyl tert-butyl ether by a Pseudomonas sp. strain grown on n-pentane

    NASA Astrophysics Data System (ADS)

    Li, S. S.; Wang, S.; Yan, W.

    2016-08-01

    When methyl tert-butyl ether (MTBE) is added as oxygenates it increases the octane number and decreases the release of nitric oxide from the incomplete combustion of reformulated gasoline. The extensive use of MTBE allowed it to be detectable as a pollutant in both ground-level and underground water worldwide. The present study focuses on the isolation and characterization of MTB-degrading microorganisms by cometabolism based on the results of growth on different carbon sources. It also focuses on the kinetic analysis and the continuous degradation of MTBE. A bacterial strain WL1 that can grow on both n-alkanes (C5-C8) and aromatics was isolated and named Pseudomonas sp. WL1 according to the 16S rDNA sequencing analysis. Strain WL1 could cometabolically degrade MTBE in the presence of n-alkanes with a desirable degradation rate. Diverse n-alkanes with different lengths of carbon chains showed significant influence on the degradation rate of MTBE and accumulation of tert-butyl alcohol (TBA). When strain WL1 cometabolically degraded MTBE in the presence of n-pentane, higher MTBE-degrading rate and lower TBA-accumulation were observed (Vmax = 38.1 nmol/min/mgprotei, Ks = 6.8 mmol/L). In the continuous degrading experiment, the removal efficiency of MTBE by Pseudomonas sp. WL1 did not show any obvious decrease after five subsequent additions.

  2. Microencapsulation, chemical characterization, and antimicrobial activity of Mexican (Lippia graveolens H.B.K.) and European (Origanum vulgare L.) oregano essential oils.

    PubMed

    Hernández-Hernández, Elvia; Regalado-González, Carlos; Vázquez-Landaverde, Pedro; Guerrero-Legarreta, Isabel; García-Almendárez, Blanca E

    2014-01-01

    The effect of solvent polarity (methanol and pentane) on the chemical composition of hydrodistilled essential oils (EO's) of Lippia graveolens H.B.K. (MXO) and Origanum vulgare L. (EUO) was studied by GC-MS. Composition of modified starch microencapsulated EO's was conducted by headspace-solid-phase microextraction (HS-SPME). The antimicrobial activity of free and microencapsulated EO's was evaluated. They were tested against Salmonella sp., Brochothrix thermosphacta, Pseudomonas fragi, Lactobacillus plantarum, and Micrococcus luteus. Thymol and carvacrol were among the main components of EO's and their free and microencapsulated inhibitory activity was tested against M. luteus, showing an additive combined effect. Chemical composition of EO's varied according to the solvent used for GC analysis and to volatile fraction as evaluated by HS-SPME. Thymol (both solvents) was the main component in essential oil of MXO, while carvacrol was the main component of the volatile fraction. EUO showed α-pinene (methanol) and γ-terpinene (pentane) as major constituents, the latter being the main component of the volatile fraction. EO's showed good stability after 3 months storage at 4°C, where antimicrobial activity of microencapsulated EO's remained the same, while free EO's decreased 41% (MXO) and 67% (EUO) from initial activity. Microencapsulation retains most antimicrobial activity and improves stability of EO's from oregano.

  3. Characterizations of volatile organic compounds (VOCs) from vehicular emissions at roadside environment: The first comprehensive study in Northwestern China

    NASA Astrophysics Data System (ADS)

    Li, Bowei; Ho, Steven Sai Hang; Xue, Yonggang; Huang, Yu; Wang, Liqin; Cheng, Yan; Dai, Wenting; Zhong, Haobin; Cao, Junji; Lee, Shuncheng

    2017-07-01

    Vehicular emission (VE) is one of the important anthropogenic sources for ground-level volatile organic compounds (VOCs) in both urban and suburban areas. A first comprehensive campaign was conducted at an urban roadside in Xi'an, China in summer, 2016. A total of 57 VOCs, as known as critical surface ozone (O3) precursors, and other trace gases were measured simultaneously during the sampling period. Iso-pentane, a tracer of gasoline evaporation, was the most abundant VOC in the roadside samples, followed by isobutane and benzene, attributed to the largest composition (∼70%) of gasoline-fueled vehicles on the road. The molar ratio of toluene/benzene (T/B) in our study (0.36) is far lower than the range reported in other cities, indicating the stronger contributions from diesel emissions. The results of source apportionment achieved with positive matrix factorization (PMF) receptor model were highly consistent with the vehicles compositions, strongly evidenced that the precise characterization of the VE sources from those marker species. The degrees of individual compound contributed to O3 production were weighed by ozone formation potential (OFP). Propylene (20%), 1-butene (11%) and iso-pentane(10%) were the top three contributors at the roadside. The information of this study complements the VOCs database regarding to the VE sources in Northwestern China.

  4. Detection Identification and Quantification of Keto-Hydroperoxides in Low-Temperature Oxidation.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hansen, Nils; Moshammer, Kai; Jasper, Ahren W.

    2017-07-01

    Keto-hydroperoxides are reactive partially oxidized intermediates that play a central role in chain-branching reactions during the low-temperature oxidation of hydrocarbons. In this Perspective, we outline how these short lived species can be detected, identified, and quantified using integrated experimental and theoretical approaches. The procedures are based on direct molecular-beam sampling from reactive environments, followed by mass spectrometry with single-photon ionization, identification of fragmentation patterns, and theoretical calculations of ionization thresholds, fragment appearance energies, and photoionization cross sections. Using the oxidation of neo-pentane and tetrahydrofuran as examples, the individual steps of the experimental approaches are described in depth together with amore » detailed description of the theoretical efforts. For neo-pentane, the experimental data are consistent with the calculated ionization and fragment appearance energies of the keto-hydroperoxide, thus adding confidence to the analysis routines and the employed levels of theory. For tetrahydrofuran, multiple keto-hydroperoxide isomers are possible due to the presence of nonequivalent O 2 addition sites. Despite this additional complexity, the experimental data allow for the identification of two to four keto-hydroperoxides. Mole fraction profiles of the keto-hydroperoxides, which are quantified using calculated photoionization cross sections, are provided together with estimated uncertainties as function of the temperature of the reactive mixture and can serve as validation targets for chemically detailed mechanisms.« less

  5. Time distribution of adsorption entropy of gases on heterogeneous surfaces by reversed-flow gas chromatography.

    PubMed

    Katsanos, Nicholas A; Kapolos, John; Gavril, Dimitrios; Bakaoukas, Nicholas; Loukopoulos, Vassilios; Koliadima, Athanasia; Karaiskakis, George

    2006-09-15

    The reversed-flow gas chromatography (RF-GC) technique has been applied to measure the adsorption entropy over time, when gaseous pentane is adsorbed on the surface of two solids (gamma-alumina and a silica supported rhodium catalyst) at 393.15 and 413.15K, respectively. Utilizing experimental chromatographic data, this novel methodology also permits the simultaneous measurement of the local adsorption energy, epsilon, local equilibrium adsorbed concentration, c(s)(*), and local adsorption isotherm, theta(p, T, epsilon) in a time resolved way. In contrast with other inverse gas chromatographic methods, which determine the standard entropy at zero surface coverage, the present method operates over a wide range of surface coverage taking into account not only the adsorbate-adsorbent interaction, but also the adsorbate-adsorbate interaction. One of the most interesting observations of the present work is the fact that the interaction of n-pentane is spontaneous on the Rh/SiO(2) catalyst for a very short time interval compared to that on gamma-Al(2)O(3). This can explain the different kinetic behavior of each particular gas-solid system, and it can be attributed to the fact that large amounts of n-C(5)H(12) are present on the active sites of the Rh/SiO(2) catalyst compared to those on gamma-Al(2)O(3), as the local equilibrium adsorbed concentration values, c(s)(*), indicate.

  6. CURRICULUM MATERIALS.

    ERIC Educational Resources Information Center

    New Jersey State Dept. of Education, Trenton.

    MATERIALS ARE LISTED BY 36 TOPICS ARRANGED IN ALPHABETICAL ORDER. TOPICS INCLUDE APPRENTICE TRAINING, BAKING, DRAFTING, ENGLISH, GLASSBLOWING, HOME ECONOMICS, INDUSTRIAL CHEMISTRY, MACHINE SHOP, NEEDLE TRADES, REFRIGERATION, AND UPHOLSTERY. PRICES ARE GIVEN FOR EACH ITEM. (EL)

  7. Electroplate Short Mix

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    2017-06-19

    Modifying the surface chemistry of materials by aluminization can protect vulnerable materials from corroding in harsh environments. The industry deals with corrosion issues is to regularly inspect components and replace them with corrosion resistant components.

  8. I. the Synthesis and Coordination Chemistry of Novel 6Pi-Electron Ligands. II. Improvement of Student Writing Skills in General Chemistry Lab Reports through the Use of Calibrated Peer Review

    ERIC Educational Resources Information Center

    William, Wilson Ngambeki

    2011-01-01

    Abstract I. The goal of this study was to synthesize and characterize a set of coordination complexes containing 6pi-cationic ligands. These compounds could be extremely useful as catalysts for the polymerization of olefins that are widely used in the synthetic polymer industry. The original strategy was to synthesize the 6pi-cationic ligands…

  9. Fundamental and applied aspects of the chemistry of radioactive iodine in gas and aqueous media

    NASA Astrophysics Data System (ADS)

    Kulyukhin, Sergei A.

    2012-10-01

    The results of investigations carried out in the past 15-20 years in the chemistry of radioactive iodine in the gas phase and in aqueous media of various compositions are described systematically and analyzed. The prospects for practical application of the obtained data in various fields of nuclear power industry including accidents at nuclear power plants and enterprises engaged in spent nuclear fuel reprocessing are estimated. The bibliography includes 206 references.

  10. Rapid analysis of inner and outer bark composition of southern yellow pine bark from industrial sources

    Treesearch

    Chi-Leung So; Thomas L. Eberhardt

    2006-01-01

    Differences in bark chemistry between inner and outer bark are well known and may affect the suitability of various bark supplies for a particular application. Accordingly, there is a need for quality control protocols to assess variability and predict product yields. Southern yellow pine bark samples from two industrial sources were separated into inner and outer bark...

  11. Capturing of the monoterpene olefin limonene produced in Saccharomyces cerevisiae.

    PubMed

    Jongedijk, Esmer; Cankar, Katarina; Ranzijn, Jorn; van der Krol, Sander; Bouwmeester, Harro; Beekwilder, Jules

    2015-01-01

    Monoterpene olefins such as limonene are plant compounds with applications as flavouring and fragrance agents, as solvents and potentially also in polymer and fuel chemistry. We engineered baker's yeast Saccharomyces cerevisiae to express a (-)-limonene synthase from Perilla frutescens and a (+)-limonene synthase from Citrus limon. Both proteins were expressed either with their native plastid targeting signal or in a truncated form in which the plastidial sorting signal was removed. The yeast host strain for expression was AE9 K197G, which expresses a mutant Erg20 enzyme. This enzyme catalyses the formation of geranyl diphosphate, which is the precursor for monoterpenes. Several methods were tested to capture limonene produced by the yeast. Extraction from the culture medium by pentane, or by the addition of CaCl2 followed by solid-phase micro-extraction, did not lead to detectable limonene, indicating that limonene is rapidly lost from the culture medium. Volatile terpenes such as limonene may also be trapped in a dodecane phase added to the medium during fermentation. This method resulted in recovery of 0.028 mg/l (+)-limonene and 0.060 mg/l (-)-limonene in strains using the truncated Citrus and Perilla synthases, respectively. Trapping the headspace during culture of the limonene synthase-expressing strains resulted in higher titres, at 0.12 mg/l (+)-limonene and 0.49 mg/l (-)-limonene. These results show that the volatile properties of the olefins produced require specific methods for efficient recovery of these molecules from biotechnological production systems. Copyright © 2014 John Wiley & Sons, Ltd.

  12. A Unique Master's Program in Combined Nuclear Technology and Nuclear Chemistry at Chalmers University of Technology, Sweden

    NASA Astrophysics Data System (ADS)

    Skarnemark, Gunnar; Allard, Stefan; Ekberg, Christian; Nordlund, Anders

    2009-08-01

    The need for engineers and scientists who can ensure safe and secure use of nuclear energy is large in Sweden and internationally. Chalmers University of Technology is therefore launching a new 2-year master's program in Nuclear Engineering, with start from the autumn of 2009. The program is open to Swedish and foreign students. The program starts with compulsory courses dealing with the basics of nuclear chemistry and physics, radiation protection, nuclear power and reactors, nuclear fuel supply, nuclear waste management and nuclear safety and security. There are also compulsory courses in nuclear industry applications and sustainable energy futures. The subsequent elective courses can be chosen freely but there is also a possibility to choose informal tracks that concentrate on nuclear chemistry or reactor technology and physics. The nuclear chemistry track comprises courses in e.g. chemistry of lanthanides, actinides and transactinides, solvent extraction, radioecology and radioanalytical chemistry and radiopharmaceuticals. The program is finished with a one semester thesis project. This is probably a unique master program in the sense of its combination of deep courses in both nuclear technology and nuclear chemistry.

  13. A database of georeferenced nutrient chemistry data for mountain lakes of the Western United States

    PubMed Central

    Williams, Jason; Labou, Stephanie G.

    2017-01-01

    Human activities have increased atmospheric nitrogen and phosphorus deposition rates relative to pre-industrial background. In the Western U.S., anthropogenic nutrient deposition has increased nutrient concentrations and stimulated algal growth in at least some remote mountain lakes. The Georeferenced Lake Nutrient Chemistry (GLNC) Database was constructed to create a spatially-extensive lake chemistry database needed to assess atmospheric nutrient deposition effects on Western U.S. mountain lakes. The database includes nitrogen and phosphorus water chemistry data spanning 1964–2015, with 148,336 chemistry results from 51,048 samples collected across 3,602 lakes in the Western U.S. Data were obtained from public databases, government agencies, scientific literature, and researchers, and were formatted into a consistent table structure. All data are georeferenced to a modified version of the National Hydrography Dataset Plus version 2. The database is transparent and reproducible; R code and input files used to format data are provided in an appendix. The database will likely be useful to those assessing spatial patterns of lake nutrient chemistry associated with atmospheric deposition or other environmental stressors. PMID:28509907

  14. Research for the advancement of green chemistry practice: Studies in atmospheric and educational chemistry

    NASA Astrophysics Data System (ADS)

    Cullipher, Steven Gene

    Green chemistry is a philosophy of chemistry that emphasizes a decreasing dependence on limited non-renewable resources and an increasing focus on preventing pollution byproducts of the chemical industry. In short, it is the discipline of chemistry practiced through the lens of environmental stewardship. In an effort to advance the practice of green chemistry, three studies will be described that have ramifications for the practice. The first study examines the atmospheric oxidation of a hydrofluorinated ether, a third-generation CFC replacement compound with primarily unknown atmospheric degradation products. Determination of these products has the potential to impact decisions on refrigerant usage in the future. The second study examines chemistry students' development of understanding benefits-costs-risks analysis when presented with two real-world scenarios: refrigerant choice and fuel choice. By studying how benefits-costs-risks thinking develops, curricular materials and instructional approaches can be designed to better foster the development of an ability that is both necessary for green chemists and important in daily decision-making for non-chemists. The final study uses eye tracking technology to examine students' abilities to interpret molecular properties from structural information in the context of global warming. Such abilities are fundamental if chemists are to appropriately assess risks and hazards of chemistry practice.

  15. Ionic liquid syntheses via click chemistry: expeditious routes toward versatile functional materials.

    PubMed

    Mirjafari, Arsalan

    2018-03-25

    Since the introduction of click chemistry by K. B. Sharpless in 2001, its exploration and exploitation has occurred in countless fields of materials sciences in both academic and industrial spheres. Click chemistry is defined as an efficient, robust, and orthogonal synthetic platform for the facile formation of new carbon-heteroatom bonds, using readily available starting materials. Premier examples of click reactions are copper(i)-catalyzed azide-alkyne Huisgen cycloaddition (CuAAC) and the thiol-X (X = ene and yne) coupling reactions to form C-N and C-S bonds, respectively. The emphasis of this review is centered on the rapidly expanding area of click chemistry-mediated synthesis of functional ionic liquids via CuAAC, thiol-X and oxime formation, and selected examples of nucleophilic ring-opening reactions, while offering some thoughts on emerging challenges, opportunities and ultimately the evolution of this field. Click chemistry offers tremendous opportunities, and introduces intriguing perspectives for efficient and robust generation of tailored task-specific ionic liquids - an important class of soft materials.

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

    PubMed

    Rotella, David P

    2016-10-19

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

  17. JPRS Report. Soviet Union, EKO: Economics & Organization of Industrial Production No. 7, July 1987.

    DTIC Science & Technology

    1987-12-03

    to the question of the interest in plasma equip- ment in various branches of the national economy. Plasma processes occupy a leading position among...the principally new technologies that are based on process - ing concentrated flows of energy. Even today there are more than 50 of them. An entire...branch of chemistry has been formed—plasma chemistry, for which it is typical to have processes with an average mass temperature of the working gas

  18. Quantification of petroleum-type hydrocarbons in avian tissue

    USGS Publications Warehouse

    Gay, M.L.; Belisle, A.A.; Patton, J.F.

    1980-01-01

    Methods were developed for the analysis of 16 hydrocarbons in avian tissue. Mechanical extraction with pentane was followed by clean-up on Florisil and Silicar. Residues were determined by gas—liquid chromatography and gas—liquid, chromatography—mass spectrometry. The method was applied to the analysis of liver, kidney, fat, and brain tissue of mallard ducks (Anas platyrhynchos) fed a mixture of hydrocarbons. Measurable concentrations of all compounds analyzed were present in all tissues except brain. Highest concentrations were in fat.

  19. Sample Collection, Analysis, and Respirator Use With Isocyanate Paints

    DTIC Science & Technology

    1990-02-01

    waterbath. 4. Acetonitrile. 6. Vials, 20-m. glass, with polypropylene-lined screw 5. Deionized water . caps. 6. Pentane. 7. Vials, 4-mK glass, with screw...Evaporator, Mini-Vap. 6 port, n, eqjivalent. sodium acetate in 1 L deionized 15. Flask, filtration, 500-mt. water . Add 1 L acetonitrile. Add 16. Funnel...methanol toie 5 mi way be stored at -21 uin the dark for at least solution. four weeks. Limit peibd of storage of samler at 6. Water , distilled. 25 *C

  20. Regioselective alkane hydroxylation with a mutant CYP153A6 enzyme

    DOEpatents

    Koch, Daniel J.; Arnold, Frances H.

    2013-01-29

    Cytochrome P450 CYP153A6 from Myobacterium sp. strain HXN1500 was engineered using in-vivo directed evolution to hydroxylate small-chain alkanes regioselectively. Mutant CYP153A6-BMO1 selectively hydroxylates butane and pentane at the terminal carbon to form 1-butanol and 1-pentanol, respectively, at rates greater than wild-type CYP153A6 enzymes. This biocatalyst is highly active for small-chain alkane substrates and the regioselectivity is retained in whole-cell biotransformations.

  1. Ending America’s Energy Insecurity: How Electric Vehicles Can Drive the Solution to Energy Independence

    DTIC Science & Technology

    2011-12-01

    road oil, aviation gasoline, kerosene, lubricants, naphtha-type jet fuel, pentanes plus, petrochemical feedstocks, special naphthas, still gas... refinery gas), waxes, miscellaneous products, and crude oil burned as fuel. Figure 2. Uses of Oil (EIA, 2010a, p. 148) There is no significant body of...1. Large-Scale Efforts in the 1990s There have been efforts in the past to bring about the adoption of EVs or other zero- emissions vehicles. There

  2. Development of Biodegradable Polyphosphazene- Nanohydroxyapatite Composite Nanofibers Via Electrospinning

    DTIC Science & Technology

    2005-01-01

    transmission electron microscopy (TEM), gravimetry and energy dispersive X-ray mapping. This study demonstrated the feasibility of developing novel composite...successive precipitations into hexane (3x) and pentane (2x). The product was an off-white fibrous material. 31P NMR: (CDC13), ppm 3 -1.1. ’H NMR (CDC13), ppm...determined by gravimetry . Theoretical loading of 50% (w/w) of the nanofibers showed an actual loading of 59% (w/w) of nHAp in the nanofiber matrix. This

  3. Investigation of Molecular Exchange Using DEXSY with Ultra-High Pulsed Field Gradients

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gratz, Marcel; Galvosas, Petrik

    2008-12-05

    Diffusion exchange spectroscopy has been employed for the investigation of water exchange between different regions of a cosmetic lotion as well as for the exchange of n-pentane between the inter- and intra-crystalline space in zeolite NaX. We successfully combined this two-dimensional (2D) NMR experiment with methods for the application of ultra-high pulsed field gradients of up to 35 T/m, resulting in observation times and mixing times as short as 2 ms and 2.8 ms, respectively.

  4. Surface chemistry changes of weathered HDPE/wood-flour composites studied by XPS and FTIR spectroscopy

    Treesearch

    Nicole M. Stark; Laurent M. Matuana

    2004-01-01

    The use of wood-derived fillers by the thermoplastic industry has been growing, fueled in part by the use of wood-fiber–thermoplastic composites by the construction industry. As a result, the durability of wood-fiber– thermoplastic composites after ultraviolet exposure has become a concern. Samples of 100% high-density polyethylene (HDPE) and HDPE filled with 50% wood-...

  5. Scaling up Effects in the Organic Laboratory

    ERIC Educational Resources Information Center

    Persson, Anna; Lindstrom, Ulf M.

    2004-01-01

    A simple and effective way of exposing chemistry students to some of the effects of scaling up an organic reaction is described. It gives the student an experience that may encounter in an industrial setting.

  6. Flow Reactors

    EPA Science Inventory

    The twelve principles of Green Chemistry presented by Anastas and Warner provide the philosophical basis and identify potential areas to increase the level of greenness in designing or implementing chemical reactions in the pharmaceutical industry. With these efforts in mind, the...

  7. "F-The French Connection."

    ERIC Educational Resources Information Center

    Sleigh, John; Plevey, Ray

    1986-01-01

    Provides background information for teachers on the chemistry of flourine. Points out that it links aerosols with refrigerants, anaesthetics with fire-fighting agents, batteries with blood substitutes, and atomic energy with the steel, petroleum, and aluminum industries. (JN)

  8. Urban impact on air quality in RegCM/CAMx couple for MEGAPOLI project - high resolution sensitivity study

    NASA Astrophysics Data System (ADS)

    Halenka, T.; Huszar, P.; Belda, M.

    2010-09-01

    Recent studies show considerable effect of atmospheric chemistry and aerosols on climate on regional and local scale. For the purpose of qualifying and quantifying the magnitude of climate forcing due to atmospheric chemistry/aerosols on regional scale, the development of coupling of regional climate model and chemistry/aerosol model was started on the Department of Meteorology and Environmental Protection, Charles University, Prague, for the EC FP6 Project QUANTIFY and EC FP6 Project CECILIA. For this coupling, existing regional climate model and chemistry transport model have been used at very high resolution of 10km grid. Climate is calculated using RegCM while chemistry is solved by CAMx. The experiments with the couple have been prepared for EC FP7 project MEGAPOLI assessing the impact of the megacities and industrialized areas on climate. Meteorological fields generated by RCM drive CAMx transport, chemistry and a dry/wet deposition. A preprocessor utility was developed for transforming RegCM provided fields to CAMx input fields and format. New domain have been settled for MEGAPOLI purpose in 10km resolution including all the European "megacities" regions, i.e. London metropolitan area, Paris region, industrialized Ruhr area, Po valley etc. There is critical issue of the emission inventories available for 10km resolution including the urban hot-spots, TNO emissions are adopted for this sensitivity study in 10km resolution for comparison of the results with the simulation based on merged TNO emissions, i.e. basically original EMEP emissions at 50 km grid. The sensitivity test to switch on/off Paris area emissions is analysed as well. Preliminary results for year 2005 are presented and discussed to reveal whether the concept of effective emission indices could help to parameterize the urban plume effects in lower resolution models. Interactive coupling is compared to study the potential of possible impact of urban air-pollution to the urban area climate.

  9. Barriers to the implementation of green chemistry in the United States.

    PubMed

    Matus, Kira J M; Clark, William C; Anastas, Paul T; Zimmerman, Julie B

    2012-10-16

    This paper investigates the conditions under which firms are able to develop and implement innovations with sustainable development benefits. In particular, we examine "green chemistry" innovations in the United States. Via interviews with green chemistry leaders from industry, academia, nongovernmental institutions (NGOs), and government, we identified six major categories of challenges commonly confronted by innovators: (1) economic and financial, (2) regulatory, (3) technical, (4) organizational, (5) cultural, and (6) definition and metrics. Further analysis of these barriers shows that in the United States, two elements of these that are particular to the implementation of green chemistry innovations are the absence of clear definitions and metrics for use by researchers and decision makers, as well as the interdisciplinary demands of these innovations on researchers and management. Finally, we conclude with some of the strategies that have been successful thus far in overcoming these barriers, and the types of policies which could have positive impacts moving forward.

  10. The role of "inert" surface chemistry in marine biofouling prevention.

    PubMed

    Rosenhahn, Axel; Schilp, Sören; Kreuzer, Hans Jürgen; Grunze, Michael

    2010-05-07

    The settlement and colonization of marine organisms on submerged man-made surfaces is a major economic problem for many marine industries. The most apparent detrimental effects of biofouling are increased fuel consumption of ships, clogging of membranes and heat exchangers, disabled underwater sensors, and growth of biofoulers in aquaculture systems. The presently common-but environmentally very problematic-way to deal with marine biofouling is to incorporate biocides, which use biocidal products in the surface coatings to kill the colonizing organisms, into the surface coatings. Since the implementation of the International Maritime Organization Treaty on biocides in 2008, the use of tributyltin (TBT) is restricted and thus environmentally benign but effective surface coatings are required. In this short review, we summarize the different strategies which are pursued in academia and industry to better understand the mechanisms of biofouling and to develop strategies which can be used for industrial products. Our focus will be on chemically "inert" model surface coatings, in particular oligo- and poly(ethylene glycol) (OEG and PEG) functionalized surface films. The reasons for choosing this class of chemistry as an example are three-fold: Firstly, experiments on spore settlement on OEG and PEG coatings help to understand the mechanism of non-fouling of highly hydrated interfaces; secondly, these studies defy the common assumption that surface hydrophilicity-as measured by water contact angles-is an unambiguous and predictive tool to determine the fouling behavior on the surface; and thirdly, choosing this system is a good example for "interfacial systems chemistry": it connects the behavior of unicellular marine organisms with the antifouling properties of a hydrated surface coating with structural and electronic properties as derived from ab initio quantum mechanical calculations using the electronic wave functions of oxygen, hydrogen, and carbon. This short review is written to outline for non-experts the hierarchical structure in length- and timescale of marine biofouling and the role of surface chemistry in fouling prevention. Experts in the field are referred to more specialized recent reviews.

  11. Chemistry Notes

    ERIC Educational Resources Information Center

    School Science Review, 1972

    1972-01-01

    Short articles describing the construction of a self-testing device for learning ionic formulae, problems with standard'' experiments in crystallizing sulfur, preparative details for a cold-setting adhesive and vermillion dye, and providing data related to the industrial manufacture of sulphuric acid. (AL)

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

    ERIC Educational Resources Information Center

    Schmidt, Hans-Jurgen

    1973-01-01

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

  13. Life in the fast lane: high-throughput chemistry for lead generation and optimisation.

    PubMed

    Hunter, D

    2001-01-01

    The pharmaceutical industry has come under increasing pressure due to regulatory restrictions on the marketing and pricing of drugs, competition, and the escalating costs of developing new drugs. These forces can be addressed by the identification of novel targets, reductions in the development time of new drugs, and increased productivity. Emphasis has been placed on identifying and validating new targets and on lead generation: the response from industry has been very evident in genomics and high throughput screening, where new technologies have been applied, usually coupled with a high degree of automation. The combination of numerous new potential biological targets and the ability to screen large numbers of compounds against many of these targets has generated the need for large diverse compound collections. To address this requirement, high-throughput chemistry has become an integral part of the drug discovery process. Copyright 2002 Wiley-Liss, Inc.

  14. Development and Application of Gas Sensing Technologies to Enable Boiler Balancing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dutta, Prabir

    2008-12-31

    Identifying gas species and their quantification is important for optimization of many industrial applications involving high temperatures, including combustion processes. CISM (Center for Industrial Sensors and Measurements) at the Ohio State University has developed CO, O{sub 2}, NO{sub x}, and CO{sub 2} sensors based on TiO{sub 2} semiconducting oxides, zirconia and lithium phosphate based electrochemical sensors and sensor arrays for high-temperature emission control. The underlying theme in our sensor development has been the use of materials science and chemistry to promote high-temperature performance with selectivity. A review article presenting key results of our studies on CO, NO{sub x}, CO{sub 2}more » and O{sub 2} sensors is described in: Akbar, Sheikh A.; Dutta, Prabir K. Development and Application of Gas Sensing Technologies for Combustion Processes, PowerPlant Chemistry, 9(1) 2006, 28-33.« less

  15. Tighten water-chemistry control after boiler layup

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brestel, L.

    1994-01-01

    The potential for internal deposition and corrosion can affect boiler reliability by reducing thermal efficiency, tube integrity, and the time between chemical cleanings. While chemical control specifications for normal operation have been developed by consensus of manufacturers and industry, their impact on shutdowns, layups, and startups is not always appreciated. The discussion of chemical-control options applies to boiler systems operating in the medium- and high-pressure ranges. Identification and correction of root causes underlying the chemistry problems encountered and application of the principles involved should result in shorter startup times, improved control over phosphate hideout, and reduced need for chemical cleaning.more » Each of these has a significant cost impact; together, they are the true measure of a successful chemistry-control program.« less

  16. Efficient magnetic recycling of covalently attached enzymes on carbon-coated metallic nanomagnets.

    PubMed

    Zlateski, Vladimir; Fuhrer, Roland; Koehler, Fabian M; Wharry, Scott; Zeltner, Martin; Stark, Wendelin J; Moody, Thomas S; Grass, Robert N

    2014-04-16

    In the pursuit of robust and reusable biocatalysts for industrial synthetic chemistry, nanobiotechnology is currently taking a significant part. Recently, enzymes have been immobilized on different nanoscaffold supports. Carbon coated metallic nanoparticles were found to be a practically useful support for enzyme immobilization due to their large surface area, high magnetic saturation, and manipulatable surface chemistry. In this study carbon coated cobalt nanoparticles were chemically functionalized (diazonium chemistry), activated for bioconjugation (N,N-disuccinimidyl carbonate), and subsequently used in enzyme immobilization. Three enzymes, β-glucosidase, α-chymotrypsin, and lipase B were successfully covalently immobilized on the magnetic nonsupport. The enzyme-particle conjugates formed retained their activity and stability after immobilization and were efficiently recycled from milliliter to liter scales in short recycle times.

  17. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Green, D.W.; Heinrich, R.R.; Jensen, K.J.

    The Analytical Chemistry Laboratory is a full-cost-recovery service center, with the primary mission of providing a broad range of technical support services to the scientific and engineering programs at ANL. In addition, ACL conducts a research program in analytical chemistry, works on instrumental and methods development, and provides analytical services for governmental, educational, and industrial organizations. The ACL handles a wide range of analytical problems, from routine standard analyses to unique problems that require significant development of methods and techniques. The purpose of this report is to summarize the technical and administrative activities of the Analytical Chemistry Laboratory (ACL) atmore » Argonne National Laboratory (ANL) for Fiscal Year 1985 (October 1984 through September 1985). This is the second annual report for the ACL. 4 figs., 1 tab.« less

  18. The coupled atmosphere-chemistry-ocean model SOCOL-MPIOM

    NASA Astrophysics Data System (ADS)

    Muthers, S.; Anet, J. G.; Stenke, A.; Raible, C. C.; Rozanov, E.; Brönnimann, S.; Peter, T.; Arfeuille, F. X.; Shapiro, A. I.; Beer, J.; Steinhilber, F.; Brugnara, Y.; Schmutz, W.

    2014-05-01

    The newly developed atmosphere-ocean-chemistry-climate model SOCOL-MPIOM is presented by demonstrating the influence of the interactive chemistry module on the climate state and the variability. Therefore, we compare pre-industrial control simulations with (CHEM) and without (NOCHEM) interactive chemistry. In general, the influence of the chemistry on the mean state and the variability is small and mainly restricted to the stratosphere and mesosphere. The largest differences are found for the atmospheric dynamics in the polar regions, with slightly stronger northern and southern winter polar vortices in CHEM. The strengthening of the vortex is related to larger stratospheric temperature gradients, which are attributed to a parametrization of the absorption of ozone and oxygen in the Lyman-alpha, Schumann-Runge, Hartley, and Higgins bands. This effect is parametrized in the version with interactive chemistry only. A second reason for the temperature differences between CHEM and NOCHEM is related to diurnal variations in the ozone concentrations in the higher atmosphere, which are missing in NOCHEM. Furthermore, stratospheric water vapour concentrations differ substantially between the two experiments, but their effect on the temperatures is small. In both setups, the simulated intensity and variability of the northern polar vortex is inside the range of present day observations. Sudden stratospheric warming events are well reproduced in terms of their frequency, but the distribution amongst the winter months is too uniform. Additionally, the performance of SOCOL-MPIOM under changing external forcings is assessed for the period 1600-2000 using an ensemble of simulations driven by a spectral solar forcing reconstruction. The amplitude of the reconstruction is large in comparison to other state-of-the-art reconstructions, providing an upper limit for the importance of the solar signal. In the pre-industrial period (1600-1850) the simulated surface temperature trends are in reasonable agreement with temperature reconstructions, although the multi-decadal variability is more pronounced. This enhanced variability can be attributed to the variability in the solar forcing. The simulated temperature reductions during the Maunder Minimum are in the lowest probability range of the proxy records. During the Dalton Minimum, when also volcanic forcing is an important driver of temperature variations, the agreement is better. In the industrial period from 1850 onward SOCOL-MPIOM overestimates the temperature increase in comparison to observational data sets. Sensitivity simulations show that this overestimation can be attributed to the increasing trend in the solar forcing reconstruction that is used in this study and an additional warming induced by the simulated ozone changes.

  19. Doping-assisted low-pressure photoionization mass spectrometry for the real-time detection of lung cancer-related volatile organic compounds.

    PubMed

    Li, Zhen; Xu, Ce; Shu, Jinian; Yang, Bo; Zou, Yao

    2017-04-01

    Real-time detection of lung cancer-related volatile organic compounds (VOCs) is a promising, non-intrusive technique for lung cancer (LC) prescreening. In this study, a novel method was designed to enhance the detection selectivity and sensitivity of LC-related polar VOCs by dichloromethane (CH 2 Cl 2 ) doping-assisted low-pressure photoionization mass spectrometry (LPPI-MS). Compared with conventional LPPI-MS, CH 2 Cl 2 doping-assisted LPPI-MS boosted the peak intensities of n-propanol, n-pentanal, acetone, and butyl acetate in nitrogen specifically by 53, 18, 16, and 43 times, respectively. The signal intensities of their daughter ions were inhibited or reduced. At relative humidity (RH) of 20%, the sensitivities of n-propanol, n-pentanal, acetone, and butyl acetate detection ranged from 116 to 452 counts/ppbv with a detection time of 10s and R 2 >0.99 for the linear calibration curves. The method was also applicable under higher RH levels of 50% and 90%. Breath samples obtained from 10 volunteers and spiked samples were investigated. Eight-fold enhancements in the signal intensities of polar VOCs were observed in the normal and spiked samples. These preliminary results demonstrate the efficacy of the dichloromethane doping-assisted LPPI technique for the detection of LC-related polar VOCs. Further studies are indispensible to illustrating the detailed mechanism and applying the technique to breath diagnosis. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Antiplasmodial activity of plant extracts used in west African traditional medicine.

    PubMed

    Mustofa; Valentin, A; Benoit-Vical, F; Pélissier, Y; Koné-Bamba, D; Mallié, M

    2000-11-01

    Five plants originating from Ivory Coast were selected after an ethnobotanical survey, Alchornea cordifolia, Mitragyna inermis, Nauclea diderrichii, Pterocarpus santalinoides, and Terminalia glaucescens. Traditional healers for the treatment of malaria commonly used these plants. Extracts of these plants were tested on three strains of Plasmodium falciparum, FcB1-Colombia and FcM29-Cameroon (chloroquine-resistant strains) and a Nigerian chloroquine-sensitive strain. Extracts were obtained by preparing decoction in water of the powdered plant, the technique used by most of the traditional healers. A radioactive micromethod allowed the evaluation of the in vitro activity of the extracts on P. falciparum. Concentrations inhibiting 50% of the parasite growth (IC(50)) ranged from 2.34 to more than 500 microg/ml according to the plant. For the most active plants (A. cordifolia and T. glaucescens) ethanol and pentane extracts were made and tested. The IC(50) values obtained for these extracts ranged from 0.35 to 43.40 microg/ml. The stage specificity of the ethanol extracts of A. cordifolia and T. glaucescens and pentane extract of T. glaucescens on the parasite erythrocytic cycle were determined. The ethanol extract of T. glaucescens showed its highest activity at the transition from the trophozoite to the schizont stages. Cytotoxicity was estimated on human fibroblasts (HeLa) cells and a cytotoxicity/antiplasmodial index was calculated, it ranged between 5 and 21, and the best antiplasmodial extract (T. glaucescens ethanol extract) had the higher index (>20).

  1. Gas hydrates and active mud volcanism on the South Shetland continental margin, Antarctic Peninsula

    NASA Astrophysics Data System (ADS)

    Tinivella, U.; Accaino, F.; Della Vedova, B.

    2008-04-01

    During the Antarctic summer of 2003 2004, new geophysical data were acquired from aboard the R/V OGS Explora in the BSR-rich area discovered in 1996 1997 along the South Shetland continental margin off the Antarctic Peninsula. The objective of the research program, supported by the Italian National Antarctic Program (PNRA), was to verify the existence of a potential gas hydrate reservoir and to reconstruct the tectonic setting of the margin, which probably controls the extent and character of the diffused and discontinuous bottom simulating reflections. The new dataset, i.e. multibeam bathymetry, seismic profiles (airgun and chirp), and two gravity cores analysed by computer-aided tomography as well as for gas composition and content, clearly shows active mud volcanism sustained by hydrocarbon venting in the region: several vents, located mainly close to mud volcanoes, were imaged during the cruise and their occurrence identified in the sediment samples. Mud volcanoes, vents and recent slides border the gas hydrate reservoir discovered in 1996 1997. The cores are composed of stiff silty mud. In core GC01, collected in the proximity of a mud volcano ridge, the following gases were identified (maximum contents in brackets): methane (46 μg/kg), pentane (45), ethane (35), propane (34), hexane (29) and butane (28). In core GC02, collected on the flank of the Vualt mud volcano, the corresponding data are methane (0 μg/kg), pentane (45), ethane (22), propane (0), hexane (27) and butane (25).

  2. ILIDS measurements of the evaporation of fuel droplets during the intake and compression strokes in a firing lean burn engine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Skippon, S.M.; Tagaki, Y.

    1996-09-01

    The evaporation of fuel droplets is an important factor in determining the quality of mixture preparation in lean-burn engines, particularly when using open-valve injection timing, which results in large in-cylinder droplet populations. Interferometric Laser Imaging for Droplet Sizing (ILIDS) has been used to measure the in-cylinder droplet size distribution and fuel volume in the droplet phase as a function of crank angle for a typical full boiling range gasoline and three single component fuels with different boiling points: iso-pentane, iso-octane, and xylene, representing the volatilities of the light end, mid-range and heavy ends of a typical gasoline. The measurements weremore » made under firing conditions, with both open and closed valve injection timing, and at two different coolant temperatures, representing simulated cold start and fully warmed up conditions. A specially built single cylinder research engine was used, equipped with a transparent sapphire cylinder to provide all-round sidewall optical access to the cylinder interior. The engine had a four-valve leanburn head, swirl control valve and air-assisted injector. The experimental arrangements for ILIDS in a firing engine, and the optical access engine itself, are discussed in detail. The results showed significant differences in the rates of evaporation of the three fuel components: iso-pentane evaporated fully very early in the induction stroke, iso-octane droplets persisted longer, and xylene droplets persisted to the end of the compression stroke.« less

  3. A pheromone analogue affects the evaporation rate of (+)-disparlure in Lymantria dispar.

    PubMed

    Sollai, Giorgia; Murgia, Sergio; Secci, Francesco; Frongia, Angelo; Cerboneschi, Anna; Masala, Carla; Liscia, Anna; Crnjar, Roberto; Solari, Paolo

    2014-04-01

    The gypsy moth Lymantria dispar L. is a widespread pest that causes economic damage to cork oak forests. Females produce the sex pheromone (+)-(7R,8S)-epoxy-2-methyloctadecane, known as (+)-disparlure [(+)D], for long-distance attraction of conspecific males. A (+)D analogue, 2-decyl-1-oxaspiro[2.2]pentane (OXP-01), neither stimulating nor attractive by itself, causes short-time inhibition of male response in a 1:1 blend with (+)D. The authors investigated whether and how the biological activity of the natural pheromone is affected by OXP-01 on a long-time basis (up to 16 days), also by looking at possible physicochemical reciprocal interactions. Blending of (+)D with OXP-01 decreased, under low evaporation rate, the pheromone effectiveness, as assessed by electroantennogram recordings. In male trappings, within the first 24 h, OXP-01 decreased and later enhanced the blend attractiveness, but only under high evaporation rate. Gas chromatography-mass spectroscopy indicates that quantitative retrieval of (+)D from blend cartridges is higher than for pure pheromone, and nuclear magnetic resonance measurements show that OXP-01 produces, possibly by Van der Waals interactions, a bimolecular entity with pheromone causing retention and lengthening of its attractiveness over time. The biological and physicochemical interactions between (+)D and OXP-01 may provide valuable information for the optimisation of pheromone-based control strategies for gypsy moths. © 2013 Society of Chemical Industry.

  4. USSR Report, Chemistry

    DTIC Science & Technology

    1985-02-06

    of technical processes in chemical industries and shows fundamental sources of defects of various analysis methods and ways to remove them. It...their Removal 18 2.1. Methods for Analyzing Composition of Industrial Gases and Vapors.. 19. 2.1.1. Thermal Conductometric Method. 19 2.1.2...cyclododecanol (80-135°C) were purged with neon to remove oxygen and irradiated with 10 MeV pulses of 1.5 ys duration in a 3.5 cm cylindrical quartz

  5. Implementation and Evaluation of Web-Based Learning Activities on Bonding and the Structure of Matter for 10-th Grade Chemistry

    NASA Astrophysics Data System (ADS)

    Frailich, Marcel

    This study deals with the development, implementation, and evaluation of web-based activities associated with the topic of chemical bonding , as taught in 10th grade chemistry. A website was developed entitled: "Chemistry and the Chemical Industry in the Service of Mankind", its URL is: http://stwww.weizmann.ac.il/g-chem/learnchem (Kesner, Frailich, & Hofstein, 2003). The main goal of this study was to assess the educational effectiveness of website activities dealing with the chemical bonding concept. These activities include visualization tools, as well as topics relevant to daily life and industrial applications. The study investigated the effectiveness of a web-based learning environment regarding the understanding of chemical bonding concepts, students' perceptions of the classroom learning environment, their attitudes regarding the relevance of learning chemistry to everyday life, and their interest in chemistry studies. As mentioned before, in the present study we focused on activities (from the website), all of which deal with chemical bonding concept. The following are the reasons for the decision to focus on this topic: (1) Chemical bonding is a key concept that is taught in 10th grade chemistry in high school. It provides the basis for many other chemistry topics that are taught later, and (2) Chemical bonding is a difficult for students using existing tools (e. g., static models in books, ball-and- stick models), which are insufficient to demonstrate the abstract nature phenomena associated with this topic. The four activities developed for this study are (1) models of the atomic structure, (2) metals -- structure and properties, (3) ionic substances in everyday life and in industry, and (4) molecular substances -- structure, properties, and uses. The study analyzed both quantitative and qualitative research. The quantitative tools of the study included: A Semantic Differential questionnaire and a Chemistry Classroom Web-Based Learning Environment Inventory to assess students' perceptions regarding the relevance of chemistry to their life and attitude towards chemistry studies, a Feedback questionnaire that examined the students' response after performing the website activities, and an achievement test that assessed their knowledge and understanding of the concept of chemical bonding. The qualitative research included observations and interviews of both students and teachers. About twenty eight observations were made while the students preformed the Internet activities. Eighteen students and seven teachers from the experimental group, and two teachers from the comparison group were interviewed. The quantitative research reveals that the experimental group outperformed the comparison group significantly, in the achievement post-test, which examines students' understanding of chemical bonding concept. We also found from the attitude questionnaires that in most of the categories, the experimental groupdemonstrated more positive attitudes compared to comparison group. Those results are in alignment with interviews that were analyzed in which teachers and students in the experimental group suggested that the visualization tools helped students to better understand the chemical bonding concept. In addition, we found that web-based learning was a significant addition to the teacher's explanations in class, since it provided scaffolding and supported the students' learning process, and indeed promoted cooperative and active learning within a community of learners using a constructivist approach. Furthermore, the students were satisfied with the activities conducted on the website and enjoyed their chemistry learning Also, they showed significant higher awareness to the relevance of chemistry to daily life. The teachers were also satisfied with the web-based activities because they were more aware to students' difficulties in understanding the chemical bonding concept, and the visual tools help them to demonstrate abstract phenomena to their students. Moreover, the website activities caused teachers to make reflection on their instruction strategies and improve them. (Abstract shortened by UMI.)

  6. Recovery Processes of Organic Acids from Fermentation Broths in the Biomass-Based Industry.

    PubMed

    Li, Qian-Zhu; Jiang, Xing-Lin; Feng, Xin-Jun; Wang, Ji-Ming; Sun, Chao; Zhang, Hai-Bo; Xian, Mo; Liu, Hui-Zhou

    2016-01-01

    The new movement towards green chemistry and renewable feedstocks makes microbial production of chemicals more competitive. Among the numerous chemicals, organic acids are more attractive targets for process development efforts in the renewable-based biorefinery industry. However, most of the production costs in microbial processes are higher than that in chemical processes, among which over 60% are generated by separation processes. Therefore, the research of separation and purification processes is important for a promising biorefinery industry. This review highlights the progress of recovery processes in the separation and purification of organic acids, including their advantages and disadvantages, current situation, and future prospects in terms of recovery yields and industrial application.

  7. An Industrial Steam Distillation

    ERIC Educational Resources Information Center

    Potter, Frederick S.; Schuerch, Conrad

    1975-01-01

    Describes an undergraduate chemistry experiment which demonstrates the use of codistillation for the separation of substances of low volatility from nonvolatiles. Pine gum is separated into turpentine and rosin by means of codistillation with steam at temperatures above 100 degrees centigrade. (MLH)

  8. Perfluoroalkyl acids and related chemistries Toxicokinetics and modes of action

    EPA Science Inventory

    The perfluoroalkyl acid salts (both carboxylates and sulfonates, hereafter designated as PFAAs) and their derivatives are important chemicals that have numerous consumer and industrial applications. However, recent discoveries that some of these compounds have global distribution...

  9. Global Ozone and Reactive Nitrogen : Composition, Chemistry and Sources

    NASA Technical Reports Server (NTRS)

    Sing, Hanwant B.; Bradshaw, J.; Davis, D.; Gregory, G.; Talbot, R.

    1994-01-01

    Ozone plays a central role in the chemistry of the atmosphere both as an ultraviolet shield and as a source of hydroxyl radicals (OH), a potent initiator of atmospheric chemistry. There is evidence to suggest that the ozone abundance in the troposphere (0-10 km) has doubled since the industrial revolution and continues to increase to date. The principle reason for this increase is thought to be the increasing emissions of nitrogen oxides (NO(x)) from anthropogenic activities. Although NO(x) is highly reactive and its products such as HN03 are easily removed by deposition, it now appears that its chemistry is quite complex and it can be transported over long distances via its conversion to a variety of nitrates and penetrates. The sources of atmospheric NO(x) include free tropospheric sources such as lightning and subsonic aircraft, as well as surface emissions which are transported to the free troposphere via convective processes. Recent experimental and theoretical studies have tried to unravel the chemistry of reactive nitrogen species, its sources, and their role in ozone formation. In this presentation we shall describe the results from these studies.

  10. Enabling Technologies for the Future of Chemical Synthesis.

    PubMed

    Fitzpatrick, Daniel E; Battilocchio, Claudio; Ley, Steven V

    2016-03-23

    Technology is evolving at breakneck pace, changing the way we communicate, travel, find out information, and live our lives. Yet chemistry as a science has been slower to adapt to this rapidly shifting world. In this Outlook we use highlights from recent literature reports to describe how progresses in enabling technologies are altering this trend, permitting chemists to incorporate new advances into their work at all levels of the chemistry development cycle. We discuss the benefits and challenges that have arisen, impacts on academic-industry relationships, and future trends in the area of chemical synthesis.

  11. Chemistry and Pharmacology of Citrus sinensis.

    PubMed

    Favela-Hernández, Juan Manuel J; González-Santiago, Omar; Ramírez-Cabrera, Mónica A; Esquivel-Ferriño, Patricia C; Camacho-Corona, María del Rayo

    2016-02-22

    Presently the search for new drugs from natural resources is of growing interest to the pharmaceutical industry. Natural products have been the source of new drugs since ancient times. Plants are a good source of secondary metabolites which have been found to have beneficial properties. The present study is a review of the chemistry and pharmacology of Citrus sinensis. This review reveals the therapeutic potential of C. sinensis as a source of natural compounds with important activities that are beneficial for human health that could be used to develop new drugs.

  12. Editorial of the PCCP themed issue on "Solvation Science".

    PubMed

    Morgenstern, Karina; Marx, Dominik; Havenith, Martina; Muhler, Martin

    2015-04-07

    The present special issue presents exciting experimental and theoretical results in the topic of "Solvation Science", a topic that emerges from physical, theoretical, and industrial chemistry, and is also of interest to a multitude of neighboring fields, such as inorganic and organic chemistry, biochemistry, physics and engineering. We hope that the articles will be highly useful for researchers who would like to enter this newly emerging area, and that it is a valuable source for the nucleation of new ideas and collaborations to better understand the active role of the solvent in reactions.

  13. Biobased chemicals: the convergence of green chemistry with industrial biotechnology.

    PubMed

    Philp, Jim C; Ritchie, Rachael J; Allan, Jacqueline E M

    2013-04-01

    Policy issues around biobased chemicals are similar to those for biobased plastics. However, there are significant differences that arise from differences in production volumes and the more specific applications of most chemicals. The drivers for biobased chemicals production are similar to those for biobased plastics, particularly the environmental drivers. However, in Europe, biobased chemical production is further driven by the need to improve the competitiveness of the chemicals industry. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Chemistry Notes.

    ERIC Educational Resources Information Center

    School Science Review, 1979

    1979-01-01

    Included is information regarding: sucrose dehydration by sulphuric acid; an example of school-industry link in studying zinc oxide production; viscous flow in inorganic silicate glass; construction of a peristaltic pump; electrolysis; carbon dioxide preparation; electrophoresis; safety in using hydrogen and sulphuric acid; and approaches to…

  15. Review of antimicrobial and antioxidative activities of chitosans in food

    USDA-ARS?s Scientific Manuscript database

    shellfish, arises from the fact that they are reported to exhibit numerous health-related beneficial effects, including strong antibiotic and antioxidative activities in foods. The extraordinary interest in the chemistry and application in agriculture, horticulture, environmental science, industry,...

  16. The Microbial Conversion of D-Sorbitol to L-Sorbose: An Interdisciplinary Experiment Illustrating an Industrial Process.

    ERIC Educational Resources Information Center

    Volker, Eugene J.; Schultz, Clyde

    1978-01-01

    Describes an experiment that has been introduced in the organic chemistry laboratory program at Shepherd College, Shepherdstown, West Virginia. It illustrates microbial reaction and its role in the synthesis of vitamin C. (HM)

  17. Chemiluminescence of Organic Peroxides. Thermal Generation of an o-Xylylene Peroxide.

    DTIC Science & Technology

    1981-04-07

    Iq It. KEY WORDS (Countinue oni tow.e* ole At neesar did tffoiltl by *lack Mmber) ?T. chemil uminesceflce AR~~ 1 * peroxides A CIEEL therniol1ys is b...recrystallization of the result- ing residue gives a peroxidic white solid. The structure of this material was deduced from spectroscopic, osmometric...recrystallized from pentane-CH2Cl to 22 give j 36 mg (32%,) as a white solid, m.p. 1.090 (with decomposition). 1HNMR (CDC]3): 7.0-6.8 (d, 2H1); 7.9-7.2

  18. Modulated growth of nanoparticles. Application for sensing nerve gases.

    PubMed

    Virel, Ana; Saa, Laura; Pavlov, Valeri

    2009-01-01

    Hydrolysis of acetylthiocholine mediated by acetylcholine esterase yields the thiol-bearing compound thiocholine. At trace concentrations, thiocholine modulates the growth of Au-Ag nanoparticles on seeding gold nanoparticles in the presence of ascorbic acid. Inhibition of the enzyme by 1,5-bis(4-allyldimethylammoniumphenyl)pentan-3-one dibromide (BW284c51) or by diethyl p-nitrophenyl phosphate (paraoxon) produces lower yields of thiocholine, promoting the catalytic growth of Au-Ag nanoparticles. Here, we describe the development of a simple and sensitive colorimetric assay for the detection of AChE inhibitors.

  19. Modeling Joint Effects of Mixtures of Chemicals on Microorganisms Using Quantitative Structure Activity Relationships

    DTIC Science & Technology

    1993-08-22

    Cyclohexane Alk 74 133 26 Pentane Alk 70 150 27 Hexane Alk 38 47 28 Heptane Alk 18 58 29 Octane Alk 8 60 30 Bis (2-chloroethyl) ether Alc 1,600 3,025 31...Triethanolarnine Amni 900 741 SAro- aromatic; Hal- balogemmaed aliphatic; Alk - alkanes; Alc- alcohols, este’s, ketones and et Aji- amineL -5- Correlation...chemicals using laboratory grown activated sludge by synthetic feed. They adapted the OECD Method 209, using inhibition of oxygen uptake rate as the measure

  20. Activation of hydrocarbons and the octane number

    NASA Technical Reports Server (NTRS)

    Peschard, Marcel

    1939-01-01

    This report presents an examination of the history of research on engine knocking and the various types of fuels used in the investigations of this phenomenon. According to this report, the spontaneous ignition of hydrocarbons doped with oxygen follows the logarithmic law within a certain temperature range, but not above 920 degrees K. Having extended the scope of investigations to prove hydrocarbons, the curves of the mixtures burned by air should then be established by progressive replacement of pure iso-octane with heptane. Pentane was also examined in this report.

  1. Synthesis and Reactivity of a New (Methylene)Phosphine.

    DTIC Science & Technology

    1981-01-27

    the synthesis of a variety of alkyl(silylamino)- 8phosphines Similarly, if two equivalents of the silylmethyl Grignard reagent were used (eq 3), the...n-BuLi (hexane solution), and t-BuLi (pentane solution). The Grignard reagent Me 3SiCH2 MgCl was prepared in Et 0 2 2 solution from Me3SiCH 2C and Mg...trimethylsilyl)amino] (chloro)- (trimethylsilylmethyl)phosphine (1) was prepared by the "one-pot" Grignard method (eqs 1 and 2) which we have used previously for

  2. Dipotassium tetra-aqua-bis-[3,5-bis-(dicyano-methyl-ene)cyclo-pentane-1,2,4-trionato(1-)-κN]cobaltate(II).

    PubMed

    Chagas, Luciano Honorato; Janczak, Jan; Machado, Flavia C; de Oliveira, Luiz Fernando C; Diniz, Renata

    2010-11-27

    The title structure, K(2)[Co(C(11)N(4)O(3))(2)(H(2)O)(4)], is isotypic with K(2)[Fe(C(11)N(4)O(3))(2)(H(2)O)(4)]. The Co(II) atom is in a distorted octa-hedral CoN(2)O(4) geometry, forming a dianionic mononuclear entity. Each dianionic unit is associated with two potassium cations and inter-acts with adjacent units through O-H⋯N and O-H⋯O hydrogen bonds.

  3. Individual Protection Testing (Task 5 - Qualitative Fit Test Simulants)

    DTIC Science & Technology

    1990-04-01

    2- octanol 0 .00026(b) 506,000 * 2- octanone 248 4 A n-octylacetate 0.21 2,500 A Paracresol 0.001 D Pelargonic acid .00084(b) 164,000 * n-pentane 990...77 Unpleasant [107-92-6] Cinnamaldehyde-CgH80 2.5 53,000 -- 246 ---- [104-55-2] Methyl salicylate-C8H803 0.58 113,400 -- 224 99 -- [119-36-8] 2- octanol ...of the literature assessment are summarized in Table 2. Bromoacetone was eliminated because of its high acute toxicity. The candidate, 2- octanol , was

  4. Baseline Geochemistry of Natural Occurring Methane and Saline Groundwater in an Area of Unconventional Shale Gas Development Through Time

    NASA Astrophysics Data System (ADS)

    Harkness, J.; Darrah, T.; Warner, N. R.; Whyte, C. J.; Moore, M. T.; Millot, R.; Kloppmann, W.; Jackson, R. B.; Vengosh, A.

    2017-12-01

    Naturally occurring methane is nearly ubiquitous in most sedimentary basins and delineating the effects of anthropogenic contamination sources from geogenic sources is a major challenge for evaluating the impact of unconventional shale gas development on water quality. This study employs a broadly integrated study of various geochemical techniques to investigate the geochemical variations of groundwater and surface water before, during, and after hydraulic fracturing.This approache combines inorganic geochemistry (major cations and anions), stable isotopes of select inorganic constituents including strontium (87Sr/86Sr), boron (δ11B), lithium (δ7Li), and carbon (δ13C-DIC), select hydrocarbon molecular (methane, ethane, propane, butane, and pentane) and isotopic tracers (δ13C-CH4, δ13C-C2H6), tritium (3H), and noble gas elemental and isotopic composition (He, Ne, Ar) to apportion natural and anthropogenic sources of natural gas and salt contaminants both before and after drilling. Methane above 1 ccSTP/L in groundwater samples awas strongly associated with elevated salinity (chloride >50 mg/L).The geochemical and isotopic analysis indicate saline groundwater originated via naturally occurring processes, presumably from the migration of deeper methane-rich brines that have interacted extensively with coal lithologies. The chemistry and gas compostion of both saline and fresh groundwater wells did not change following the installation of nearby shale-gas wells.The results of this study emphasize the value of baseline characterization of water quality in areas of fossil fuel exploration. Overall this study presents a comprehensive geochemical framework that can be used as a template for assessing the sources of elevated hydrocarbons and salts to water resources in areas potentially impacted by oil and gas development.

  5. Low-temperature superacid catalysis: Reactions of n - butane and propane catalyzed by iron- and manganese-promoted sulfated zirconia

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsz-Keung, Cheung; d`Itri, J.L.; Lange, F.C.

    1995-12-31

    The primary goal of this project is to evaluate the potential value of solid superacid catalysts of the sulfated zirconia type for light hydrocarbon conversion. The key experiments catalytic testing of the performance of such catalysts in a flow reactor fed with streams containing, for example, n-butane or propane. Fe- and Mn-promoted sulfated zirconia was used to catalyze the conversion of n-butane at atmospheric pressure, 225-450{degrees}C, and n-butane partial pressures in the range of 0.0025-0.01 atm. At temperatures <225{degrees}C, these reactions were accompanied by cracking; at temperatures >350{degrees}C, cracking and isomerization occurred. Catalyst deactivation, resulting at least in part frommore » coke formation, was rapid. The primary cracking products were methane, ethane, ethylene, and propylene. The observation of these products along with an ethane/ethylene molar ratio of nearly 1 at 450{degrees}C is consistent with cracking occurring, at least in part, by the Haag-Dessau mechanism, whereby the strongly acidic catalyst protonates n-butane to give carbonium ions. The rate of methane formation from n-butane cracking catalyzed by Fe- and Mn-promoted sulfated zirconia at 450{degrees}C was about 3 x 10{sup -8} mol/(g of catalyst {center_dot}s). The observation of butanes, pentanes, and methane as products is consistent with Olah superacid chemistry, whereby propane is first protonated by a very strong acid to form a carbonium ion. The carbonium ion then decomposes into methane and an ethyl cation which undergoes oligocondensation reactions with propane to form higher molecular weight alkanes. The results are consistent with the identification of iron- and manganese-promoted sulfated zirconia as a superacid.« less

  6. Contribution from philosophy of chemistry to chemistry education: In a case of ionic liquids as technochemistry

    NASA Astrophysics Data System (ADS)

    Mudzakir, Ahmad; Hernani, Widhiyanti, Tuszie; Sudrajat, Devi Pratiwi

    2017-08-01

    Traditional chemistry education is commonly handing down of concepts, principles, and theories, such as mechanical properties, the relationship between structure and properties as well as chemical structure and chemical bonding theory, to students without engaging them in the processes of chemical inquiry. This practice leads to the lack of opportunity for the students to construct an appropriate understanding of these concepts, principles, and theories. Students are also rarely facilitated in modeling the structure and function of matter themselves. This situation shows that the philosophy of chemistry has not received as much attention from chemistry educators. The main idea of this paper is to embed philosophy of chemistry through the implementation of technochemistry in chemistry education. One of the most interesting and rapidly developing areas of modern chemistry, technologies and engineering is Ionic Liquids (ILs) as an emerging knowledge on technochemistry which can be applied to chemistry education. The developments between academic researchers and industrial developments in the ILs area are conducted in parallel. In order to overcome the existing problems of scientific development in chemistry education, the science and technology of ILs can be used for reconceptualizing the teaching and learning of chemistry to embrace the epistemology in chemistry. This study promises a potential contribution by philosophy of chemistry. The main objectives of this study are to develop: (i) a perspective based on philosophy of science considerations (rational reconstruction) in order to understand ionic liquids and (ii) teaching materials that can be used to enhance pre-service teacher's view of nature of science and technology (VNOST). The method used in the study is analytical-descriptive (elementarization), i.e. the first step in the model of educational reconstruction (MER). This study concludes that the development of the concepts and their applications of ionic liquids follow the inductive process. Experimental observations lead to scientific concepts which later can facilitate to elaborate explanatory theories.

  7. Estimates of the changes in tropospheric chemistry which result from human activity and their dependence on NO(x) emissions and model resolution

    NASA Technical Reports Server (NTRS)

    Kanakidou, Maria; Crutzen, Paul J.; Zimmermann, Peter H.

    1994-01-01

    As a consequence of the non-linear behavior of the chemistry of the atmosphere and because of the short lifetime of nitrogen oxides (NO(x)), two-dimensional models do not give an adequate description of the production and destruction rates of NO(x) and their effects on the distributions of the concentration of ozone and hydroxyl radical. In this study, we use a three-dimensional model to evaluate the contribution of increasing NO(x) emissions from industrial activity and biomass burning to changes in the chemical composition of the troposphere. By comparing results obtained from longitudinally-uniform and longitudinally-varying emissions of NO(x), we demonstrate that the geographical representation of the NO(x) emissions is crucial in simulating tropospheric chemistry.

  8. Natural products and combinatorial chemistry: back to the future.

    PubMed

    Ortholand, Jean-Yves; Ganesan, A

    2004-06-01

    The introduction of high-throughput synthesis and combinatorial chemistry has precipitated a global decline in the screening of natural products by the pharmaceutical industry. Some companies terminated their natural products program, despite the unproven success of the new technologies. This was a premature decision, as natural products have a long history of providing important medicinal agents. Furthermore, they occupy a complementary region of chemical space compared with the typical synthetic compound library. For these reasons, the interest in natural products has been rekindled. Various approaches have evolved that combine the power of natural products and organic chemistry, ranging from the combinatorial total synthesis of analogues to the exploration of natural product scaffolds and the design of completely unnatural molecules that resemble natural products in their molecular characteristics.

  9. Ethics in Science: The Unique Consequences of Chemistry

    PubMed Central

    Kovac, Jeffrey

    2015-01-01

    This article discusses the ethical issues unique to the science and practice of chemistry. These issues arise from chemistry’s position in the middle between the theoretical and the practical, a science concerned with molecules that are of the right size to directly affect human life. Many of the issues are raised by the central activity of chemistry––synthesis. Chemists make thousands of new substances each year. Many are beneficial, but others are threats. Since the development of the chemical industry in the nineteenth century, chemistry has contributed to the deterioration of the environment but has also helped to reduce pollution. Finally, we discuss the role of codes of ethics and whether the current codes of conduct for chemists are adequate for the challenges of today’s world. PMID:26155729

  10. Source Apportionment of VOCs in Edmonton, Alberta

    NASA Astrophysics Data System (ADS)

    McCarthy, M. C.; Brown, S. G.; Aklilu, Y.; Lyder, D. A.

    2012-12-01

    Regional emissions at Edmonton, Alberta, are complex, containing emissions from (1) transportation sources, such as cars, trucks, buses, and rail; (2) industrial sources, such as petroleum refining, light manufacturing, and fugitive emissions from holding tanks or petroleum terminals; and (3) miscellaneous sources, such as biogenic emissions and natural gas use and processing. From 2003 to 2009, whole air samples were collected at two sites in Edmonton and analyzed for over 77 volatile organic compounds (VOCs). VOCs were sampled in the downtown area (Central) and the industrial area on the eastern side of the city (East). Concentrations of most VOCs were highest at the East site. The positive matrix factorization (PMF) receptor model was used to apportion ambient concentration measurements of VOCs into eleven factors, which were associated with emissions source categories. Factors of VOCs identified in the final eleven-factor solution include transportation sources (both gasoline and diesel vehicles), industrial sources, a biogenic source, and a natural-gas-related source. Transportation sources accounted for more mass at the Central site than at the East site; this was expected because Central is in a core urban area where transportation emissions are concentrated. Transportation sources accounted for nearly half of the VOC mass at the Central site, but only 6% of the mass at the East site. Encouragingly, mass from transportation sources has declined by about 4% a year in this area; this trend is similar to the decline found throughout the United States, and is likely due to fleet turnover as older, more highly polluting cars are replaced with newer, cleaner cars. In contrast, industrial sources accounted for ten times more VOC mass at the East site than at the Central site and were responsible for most of the total VOC mass observed at the East site. Of the six industrial factors identified at the East site, four were linked to petrochemical industry production and storage. The two largest contributors to VOC mass at the East site were associated with fugitive emissions of volatile species (butanes, pentanes, hexane, and cyclohexane); together, these two factors accounted for more than 50% of the mass at the East site and less than 2% of the mass at the Central site. Natural-gas-related emissions accounted for 10% to 20% of the mass at both sites. Biogenic emissions and VOCs associated with well-mixed global background were less than 10% of the VOC mass at the Central site and less than 3% of the mass at the East site. Controllable emissions sources account for the bulk of the identified VOC mass. Efforts to reduce ozone or particulate matter precursors or exposure to toxic pollutants can now be directed to those sources most important to the Edmonton area.

  11. Design of Molecular Materials: Supramolecular Engineering

    NASA Astrophysics Data System (ADS)

    Simon, Jacques; Bassoul, Pierre

    2001-02-01

    This timely and fascinating book is destined to be recognised as THE book on supramolecular engineering protocols. It covers this sometimes difficult subject in an approachable form, gathering together information from many sources. Supramolecular chemistry, which links organic chemistry to materials science, is one of the fastest growth areas of chemistry research. This book creates a correlation between the structure of single molecules and the physical and chemical properties of the resulting materials. By making systematic changes to the component molecules, the resulting solid can be engineered for optimum performance. There is a clearly written development from synthesis of designer molecules to properties of solids and further on to devices and complex materials systems, providing guidelines for mastering the organisation of these systems. Topics covered include: Systemic chemistry Molecular assemblies Notions of symmetry Supramolecular engineering Principe de Curie Organisation in molecular media Molecular semiconductors Industrial applications of molecular materials This superb book will be invaluable to researchers in the field of supramolecular materials and also to students and teachers of the subject.

  12. Current Status and Future Perspectives in Flavor Research: Highlights of the 11th Wartburg Symposium on Flavor Chemistry & Biology.

    PubMed

    Hofmann, Thomas; Krautwurst, Dietmar; Schieberle, Peter

    2018-03-14

    The 11th Wartburg Symposium on Flavor Chemistry & Biology, held at the hotel "Auf der Wartburg" in Eisenach, Germany, from June 21 to 24 in 2016, offered a venue for global exchange on cutting-edge research in chemistry and biology of odor and taste. The focus areas were (1) functional flavor genomics and biotechnology, (2) flavor generation and precursors, (3) new approaches and precursors, (4) new approaches and technologies, (5) new molecules and structure/activity relationships, (6) food-borne bioactives and chemosensory health prevention, and (7) chemosensory reception, processing, and perception. Selected from more than 250 applicants, 160 distinguished scientists and rising stars from academia and industry from 24 countries participated in this multidisciplinary event. This special issue comprises a selection of 33 papers from oral presentations and poster contributions and is prefaced by this symposium introduction to carve out essential achievements in odor and taste chemistry and to share future research perspectives.

  13. Science in Connecticut Classrooms.

    ERIC Educational Resources Information Center

    Bourquin, Eugene

    1985-01-01

    Outlines a science-industrial arts survey course which presents basic concepts of chemistry as applied to practical experiences. Course topics include: paints; solvents; finishes; metallurgy of iron; precious metals; calorimetry; fossil fuels; batteries; adhesives; cement; and others. The short units were designed for students with limited…

  14. Commission on the Future of the United States Aerospace Industry

    DTIC Science & Technology

    2002-11-01

    ballistics of a baseball, computing gas mileage in Corvettes, the chemistry of cosmetics , etc.) provokes student interest in core scientific areas... Fenton Carey, Deputy Director for Production Department of Transportation/Federal Aviation Administration Permanent Staff Mr. William J. Bihner, Jr

  15. THE INFLUENCE OF SOURCE AND CHEMISTRY ON THE TOXICITY OF AMBIENT PARTICULATE MATTER

    EPA Science Inventory

    Air pollution has long been associated with detrimental health risks in susceptible populations. Experimental evidence in rodents indicates that inhaled or instilled particles from heavy industry, diesel exhaust particles, woodsmoke or collected from different locations can caus...

  16. Navigating through the domains of biology and chemistry

    EPA Science Inventory

    Developing computational toxicology methods to assist the risk assessment process has recently gained much attention both in regulatory agencies and industries. The FDA Center for Food Safety and Applied Nutrition’s Office of Food Additive Safety (CFSAN OFAS) uses (Q)SAR approach...

  17. Recent trends in laboratory automation in the pharmaceutical industry.

    PubMed

    Rutherford, M L; Stinger, T

    2001-05-01

    The impact of robotics and automation on the pharmaceutical industry over the last two decades has been significant. In the last ten years, the emphasis of laboratory automation has shifted from the support of manufactured products and quality control of laboratory applications, to research and development. This shift has been the direct result of an increased emphasis on the identification, development and eventual marketing of innovative new products. In this article, we will briefly identify and discuss some of the current trends in laboratory automation in the pharmaceutical industry as they apply to research and development, including screening, sample management, combinatorial chemistry, ADME/Tox and pharmacokinetics.

  18. DOE Office of Scientific and Technical Information (OSTI.GOV)

    King, Paul W; Chen, Jingguang G.; Crooks, Richard M.

    Nitrogen is fundamental to all of life and many industrial processes. The interchange of nitrogen oxidation states in the industrial production of ammonia, nitric acid, and other commodity chemicals is largely powered by fossil fuels. A key goal of contemporary research in the field of nitrogen chemistry is to minimize the use of fossil fuels by developing more efficient heterogeneous, homogeneous, photo-, and electrocatalytic processes or by adapting the enzymatic processes underlying the natural nitrogen cycle. These approaches, as well as the challenges involved, are discussed in this Review.

  19. USGS Research on Saline Waters Co-Produced with Energy Resources

    USGS Publications Warehouse

    ,

    1997-01-01

    The United States energy industry faces the challenge of satisfying our expanding thirst for energy while protecting the environment. This challenge is magnified by the increasing volumes of saline water produced with oil and gas in the Nation's aging petroleum fields. Ultimately, energy-producing companies are responsible for disposing of these waters. USGS research provides basic information, for use by regulators, industry, and the public, about the chemistry of co-produced waters and environmentally acceptable ways of handling them.

  20. Development and evaluation of GRAL-C dispersion model, a hybrid Eulerian-Lagrangian approach capturing NO-NO 2-O 3 chemistry

    NASA Astrophysics Data System (ADS)

    Oettl, Dietmar; Uhrner, Ulrich

    2011-02-01

    Based on two recent publications using Lagrangian dispersion models to simulate NO-NO 2-O 3 chemistry for industrial plumes, a similar modified approach was implemented using GRAL-C ( Graz Lagrangian Model with Chemistry) and tested on two urban applications. In the hybrid dispersion model GRAL-C, the transport and turbulent diffusion of primary species such as NO and NO 2 are treated in a Lagrangian framework while those of O 3 are treated in an Eulerian framework. GRAL-C was employed on a one year street canyon simulation in Berlin and on a four-day simulation during a winter season in Graz, the second biggest city in Austria. In contrast to Middleton D.R., Jones A.R., Redington A.L., Thomson D.J., Sokhi R.S., Luhana L., Fisher B.E.A. (2008. Lagrangian modelling of plume chemistry for secondary pollutants in large industrial plumes. Atmospheric Environment 42, 415-427) and Alessandrini S., Ferrero E. (2008. A Lagrangian model with chemical reactions: application in real atmosphere. Proceedings of the 12th Int. Conf. on Harmonization within atmospheric dispersion modelling for regulatory purposes. Croatian Meteorological Journal, 43, ISSN: 1330-0083, 235-239) the treatment of ozone was modified in order to facilitate urban scale simulations encompassing dense road networks. For the street canyon application, modelled daily mean NO x/NO 2 concentrations deviated by +0.4%/-15% from observations, while the correlations for NO x and NO 2 were 0.67 and 0.76 respectively. NO 2 concentrations were underestimated in summer, but were captured well for other seasons. In Graz a fair agreement for NO x and NO 2 was obtained between observed and modelled values for NO x and NO 2. Simulated diurnal cycles of NO 2 and O 3 matched observations reasonably well, although O 3 was underestimated during the day. A possible explanation here might lie in the non-consideration of volatile organic compounds (VOCs) chemistry.

  1. Flow microreactor synthesis in organo-fluorine chemistry

    PubMed Central

    Nagaki, Aiichiro

    2013-01-01

    Summary Organo-fluorine compounds are the substances of considerable interest in various industrial fields due to their unique physical and chemical properties. Despite increased demand in wide fields of science, synthesis of fluoro-organic compounds is still often faced with problems such as the difficulties in handling of fluorinating reagents and in controlling of chemical reactions. Recently, flow microreactor synthesis has emerged as a new methodology for producing chemical substances with high efficiency. This review outlines the successful examples of synthesis and reactions of fluorine-containing molecules by the use of flow microreactor systems to overcome long-standing problems in fluorine chemistry. PMID:24367443

  2. Flow microreactor synthesis in organo-fluorine chemistry.

    PubMed

    Amii, Hideki; Nagaki, Aiichiro; Yoshida, Jun-Ichi

    2013-12-05

    Organo-fluorine compounds are the substances of considerable interest in various industrial fields due to their unique physical and chemical properties. Despite increased demand in wide fields of science, synthesis of fluoro-organic compounds is still often faced with problems such as the difficulties in handling of fluorinating reagents and in controlling of chemical reactions. Recently, flow microreactor synthesis has emerged as a new methodology for producing chemical substances with high efficiency. This review outlines the successful examples of synthesis and reactions of fluorine-containing molecules by the use of flow microreactor systems to overcome long-standing problems in fluorine chemistry.

  3. Enabling Technologies for the Future of Chemical Synthesis

    PubMed Central

    2016-01-01

    Technology is evolving at breakneck pace, changing the way we communicate, travel, find out information, and live our lives. Yet chemistry as a science has been slower to adapt to this rapidly shifting world. In this Outlook we use highlights from recent literature reports to describe how progresses in enabling technologies are altering this trend, permitting chemists to incorporate new advances into their work at all levels of the chemistry development cycle. We discuss the benefits and challenges that have arisen, impacts on academic–industry relationships, and future trends in the area of chemical synthesis. PMID:27163040

  4. Development of New Transferable Coarse-Grained Models of Hydrocarbons.

    PubMed

    An, Yaxin; Bejagam, Karteek K; Deshmukh, Sanket A

    2018-06-21

    We have utilized an approach that integrates molecular dynamics (MD) simulations with particle swarm optimization (PSO) to accelerate the development of coarse-grained (CG) models of hydrocarbons. Specifically, we have developed new transferable CG beads, which can be used to model the hydrocarbons (C5 to C17) and reproduce their experimental properties with good accuracy. Firstly, the PSO method was used to develop the CG beads of the decane model represented with 2:1 (2-2-2-2-2) mapping scheme. This was followed by the development of the nonane model described with hybrid 2-2-3-2, and 3:1 (3-3-3) mapping schemes. The force-field (FF) parameters for these three CG models were optimized to reproduce four experimentally observed properties including density, enthalpy of vaporization, surface tension, and self-diffusion coefficient at 300 K. The CG MD simulations conducted with these new CG models of decane and nonane, at different timesteps, for various system sizes, and at a range of different temperatures, were able to predict their density, enthalpy of vaporization, surface tension, self-diffusion coefficient, expansibility, and isothermal compressibility with a good accuracy. Moreover, comparison of structural features obtained from the CG MD simulations and the CG beads of mapped all-atom (AA) trajectories of decane and nonane showed very good agreement. To test the chemical transferability of these models, we have constructed the models for hydrocarbons ranging from pentane to heptadecane, by using different combination of the CG beads of decane and nonane. The properties of pentane to heptadecane predicted by these new CG models showed an excellent agreement with the experimental data.

  5. Reaction of the thermo-labile triazenide Na[tBu3SiNNNSiMe3] with CO2: formation of the imido carbonate (tBu3SiO)(Me3SiO)C[double bond, length as m-dash]N-SitBu3 and carbamine acid (tBu3SiO)CONH2.

    PubMed

    Lerner, H-W; Bolte, M; Wagner, M

    2017-07-11

    The thermo-labile triazenide Na[tBu 3 SiNNNSiMe 3 ] was prepared by the reaction of Me 3 SiN 3 with Na(thf) 2 [SitBu 3 ] in pentane at -78 °C. Treatment of Na[tBu 3 SiNNNSiMe 3 ] with an excess of carbon dioxide in pentane at -78 °C yielded the imido carbonate (tBu 3 SiO)(Me 3 SiO)C[double bond, length as m-dash]N-SitBu 3 and the carbamine acid (tBu 3 SiO)CONH 2 along with other products. From the reaction solution we could isolate the imido carbonate (tBu 3 SiO)(Me 3 SiO)C[double bond, length as m-dash]N-SitBu 3 and carbamine acid (tBu 3 SiO)CONH 2 . At first single crystals of the carbamine acid (tBu 3 SiO)CONH 2 (triclinic, space group P1[combining macron]) were grown from this solution at room temperature. A second crop of crystals were obtained by concentrating the solution. The second charge consisted of the imido carbonate (tBu 3 SiO)(Me 3 SiO)C[double bond, length as m-dash]N-SitBu 3 (monoclinic, space group P2 1 /n).

  6. Thiobarbituric acid reactive substances and volatile compounds in chicken breast meat infused with plant extracts and subjected to electron beam irradiation.

    PubMed

    Rababah, T; Hettiarachchy, N S; Horax, R; Cho, M J; Davis, B; Dickson, J

    2006-06-01

    The effect of irradiation on thiobarbituric acid reactive substances (TBARS) and volatile compounds in raw and cooked nonirradiated and irradiated chicken breast meat infused with green tea and grape seed extracts was investigated. Chicken breast meat was vacuum infused with green tea extract (3,000 ppm), grape seed extract (3,000 ppm), or their combination (at a total of 6,000 ppm), irradiated with an electron beam, and stored at 5 degrees C for 12 d. The targeted irradiation dosage was 3.0 kGy and the average absorbed dosage was 3.12 kGy. Values of TBARS and volatile compound contents of raw and cooked chicken meat were determined during the 12-d storage period. Thiobarbituric acid reactive substances values ranged from 15.5 to 71.4 mg of malondialdehyde/kg for nonirradiated raw chicken and 17.3 to 80.1 mg of malondialdehyde/kg for irradiated raw chicken. Values for cooked chicken ranged from 31.4 to 386.2 and 38.4 to 504.1 mg of malondialdehyde/kg for nonirradiated and irradiated chicken, respectively. Irradiation increased TBARS and hexanal values of controls and meat infused with plant extracts. Hexanal had the highest intensity of volatiles followed by pentanal and other volatiles. Cooking the samples significantly (P < 0.05) increased the amounts of TBARS and volatiles. Addition of plant extracts decreased the amount of TBARS as well as hexanal and pentanal values. Although irradiation increases lipid oxidation, infusion of chicken meat with plant extracts could reduce lipid oxidation caused by irradiation.

  7. Characteristics of atmospheric non-methane hydrocarbons during haze episode in Beijing, China.

    PubMed

    Guo, Songjun; Tan, Jihua; Duan, Jingchun; Ma, Yongliang; Yang, Fumo; He, Kebin; Hao, Jimin

    2012-12-01

    This study firstly focused on non-methane hydrocarbons (NMHCs) during three successive days with haze episode (16-18 August 2006) in Beijing. Concentrations of alkanes, alkenes, aromatic hydrocarbons, and ethyne all peaked at traffic rush hour, implying vehicular emission; and alkanes also peaked at non-traffic rush hour in the daytime, implying additional source. Especially, alkanes and aromatics clearly showed higher levels in the nighttime than that in the daytime, implying their active photochemical reactions in the daytime. Correlation coefficients (R (2)) showed that propane, n-butane, i-butane, ethene, propene, and benzene correlated with ethyne (R (2) = 0.61-0.66), suggesting that their main source is vehicular emission; 2-methylpentane and n-hexane correlated with i-pentane (R (2) = 0.61-0.64), suggesting that gasoline evaporation is their main source; and ethylbezene, m-/p-xylene, and o-xylene correlated with toluene (R (2) = 0.60-0.79), suggesting that their main source is similar to that of toluene (e.g., solvent usage). The R (2) of ethyne, i-pentane, and toluene with total NMHCs were 0.58, 0.76, and 0.60, respectively, indicating that ambient hydrocarbons are associated with vehicular emission, gasoline evaporation, and solvent usage. The sources of other hydrocarbons (e.g., ethane) might be natural gas leakage, biogenic emission, or long-range transport of air pollutants. Measured higher mean B/T ratio (0.78 ± 0.27) was caused by the more intensive photochemical activity of toluene than benzene, still indicating the dominant emission from vehicles.

  8. What can we learn about dispersion from the conformer surface of n-pentane?

    PubMed

    Martin, Jan M L

    2013-04-11

    In earlier work [Gruzman, D. ; Karton, A.; Martin, J. M. L. J. Phys. Chem. A 2009, 113, 11974], we showed that conformer energies in alkanes (and other systems) are highly dispersion-driven and that uncorrected DFT functionals fail badly at reproducing them, while simple empirical dispersion corrections tend to overcorrect. To gain greater insight into the nature of the phenomenon, we have mapped the torsional surface of n-pentane to 10-degree resolution at the CCSD(T)-F12 level near the basis set limit. The data obtained have been decomposed by order of perturbation theory, excitation level, and same-spin vs opposite-spin character. A large number of approximate electronic structure methods have been considered, as well as several empirical dispersion corrections. Our chief conclusions are as follows: (a) the effect of dispersion is dominated by same-spin correlation (or triplet-pair correlation, from a different perspective); (b) singlet-pair correlation is important for the surface, but qualitatively very dissimilar to the dispersion component; (c) single and double excitations beyond third order are essentially unimportant for this surface; (d) connected triple excitations do play a role but are statistically very similar to the MP2 singlet-pair correlation; (e) the form of the damping function is crucial for good performance of empirical dispersion corrections; (f) at least in the lower-energy regions, SCS-MP2 and especially MP2.5 perform very well; (g) novel spin-component scaled double hybrid functionals such as DSD-PBEP86-D2 acquit themselves very well for this problem.

  9. The Chemistry of Beer Instability

    ERIC Educational Resources Information Center

    Stewart, Graham G.

    2004-01-01

    Brewing of beer, one of the oldest biotechnology industries was one of the earliest processes to be undertaken on commercial basis. Biological instability involves contamination of bacteria, yeast, or mycelia fungi and there is always a risk in brewing that beer can become contaminated by micro-organisms.

  10. GREEN CHEMISTRY FOR SELECTIRVE OXIDATION PROCESSES

    EPA Science Inventory

    The costs of handling, treating and disposing of wastes generated annually in the United States has reached to 2.2% of gross domestic product, and continued to rise. The chemical manufacturing industry generates more than 1.5 billion tons of hazardous waste and 9 billion tons of ...

  11. THE ROLE OF RAMAN SPECTROSCOPY IN THE ANALYTICAL CHEMISTRY OF POTABLE WATER

    EPA Science Inventory

    Advances in instrumentation are making Raman spectroscopy the tool of choice for an increasing number of chemical applications. For example, many recalcitrant industrial-process monitoring problems have been solved in recent years with in-line Raman spectrometers. Raman is attr...

  12. From Carver to Hill, and On.

    ERIC Educational Resources Information Center

    Massie, Samuel P.

    The story of blacks in chemistry is one of determination, expectation, participation and contribution. Between 1910 and 1945, despite George Washington Carver's significant agricultural contributions and St. Elmo Brady's scholarship, white graduate schools and industry had little interest in accepting blacks. There was slow progress, despite these…

  13. Potential Energy Sources Pose Mining Problem

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1974

    1974-01-01

    Summarizes the discussions of a Division of Industrial and Engineering Chemistry symposium on solids handling for synthetic fuels production. Included is a description of technical difficulties with the use of coal seams and deposits of oil shale and oil sand as potential sources of fuel. (CC)

  14. CONTROL OF CHELATOR-BASED UPSETS IN SURFACE FINISHING SHOP WASTE WATER TREATMENT SYSTEMS

    EPA Science Inventory

    Actual surface finishing shop examples are used to illustrate the use of process chemistry understanding and analyses to identify immediate, interim and permanent response options for industrial waste water treatment plant (IWTP) upset problems caused by chelating agents. There i...

  15. Plastics in Building.

    ERIC Educational Resources Information Center

    Skeist, Irving, Ed.

    The evaluation and use of plastics in the construction industry are explained. The contributors offer extensive, timely, and thoroughly researched data on the chemistry, properties, functions, engineering behavior, and specific applications of plastics to building requirements. The major subjects discussed in depth are--(1) the role of plastics in…

  16. Subject Bibliographies and Research Guides. 1985-1987.

    ERIC Educational Resources Information Center

    San Francisco State Univ., CA. J. Paul Leonard Library.

    The 35 pathfinders in this collection provide selected information about information sources at the J. Paul Leonard Library for the following subjects: Biography; Book Reviews; Broadcasting; Business; Chemistry; Cinema; Computer Science; Corporations, Stocks and Industries; Costume and Fashion; Current Events and News Sources; Economic Censuses of…

  17. Report: Industrial Hygiene: Safer Working through Analytical Chemistry.

    ERIC Educational Resources Information Center

    Hemingway, Ronald E.

    1980-01-01

    The analytical chemist is involved in the recognition, evaluation, and control of chemical hazards in the workplace environment. These goals can be achieved by setting up a monitoring program; this should be a combination of planning, calibration, sampling, and analysis of toxic substances. (SMB)

  18. Symposium on the Chemistry and Toxicology of Acrylamide

    USDA-ARS?s Scientific Manuscript database

    Acrylamide is used worldwide to synthesize polyacrylamide. The polymer has found many applications as a soil conditioner, in wastewater treatment, in the cosmetic, paper, and textile industries, and in the laboratory as a solid support for the separation of proteins by electrophoresis. Because of th...

  19. A Laboratory Course in Technological Chemistry.

    ERIC Educational Resources Information Center

    Wiseman, P.

    1986-01-01

    Describes a laboratory course taught at the University of Manchester Institute of Science and Technology (United Kingdom) which focuses on the preparation, properties, and applications of end-use products of the chemical industry. Outlines laboratory experiments on dyes, fibers, herbicides, performance testing, antioxidants, and surface active…

  20. THE ROLE OF RAMAN SPECTROSCOPY IN THE ANALYTICAL CHEMISTRY OF POTABLE WATER

    EPA Science Inventory

    Advances in instrumentation are making Raman spectroscopy the tool of choice for an increasing number of chemical applications. For example, many recalcitrant industrial process monitoring problems have been solved in recent years with in-line Raman spectrometers. Raman is attr...

  1. HYDROCARBON OXIDATION OVER VANADIUM PHOSPHORUS OXIDE CATALYST USING HYDROGEN PEROXIDE

    EPA Science Inventory

    Selective oxidation of hydrocarbons is one of the very important and challenging areas in industrial chemistry due to the wide ranging utility of the resulting oxygenates in fine chemical synthesis. Most of the existing processes for their oxidations employ toxic and often stoich...

  2. SCIP in Action in Bury.

    ERIC Educational Resources Information Center

    Dawson, Bob

    1986-01-01

    Gives an example of a class project dealing with pollution developed by one school involved in the School Curriculum Industry Project. Discusses investigations covering a three-week period in which chemistry students were involved in audiovisual productions, field trips to pollution treatment centers, and small group presentations. (TW)

  3. Halogen-Mediated Conversion of Hydrocarbons to Commodities.

    PubMed

    Lin, Ronghe; Amrute, Amol P; Pérez-Ramírez, Javier

    2017-03-08

    Halogen chemistry plays a central role in the industrial manufacture of various important chemicals, pharmaceuticals, and polymers. It involves the reaction of halogens or halides with hydrocarbons, leading to intermediate compounds which are readily converted to valuable commodities. These transformations, predominantly mediated by heterogeneous catalysts, have long been successfully applied in the production of polymers. Recent discoveries of abundant conventional and unconventional natural gas reserves have revitalized strong interest in these processes as the most cost-effective gas-to-liquid technologies. This review provides an in-depth analysis of the fundamental understanding and applied relevance of halogen chemistry in polymer industries (polyvinyl chloride, polyurethanes, and polycarbonates) and in the activation of light hydrocarbons. The reactions of particular interest include halogenation and oxyhalogenation of alkanes and alkenes, dehydrogenation of alkanes, conversion of alkyl halides, and oxidation of hydrogen halides, with emphasis on the catalyst, reactor, and process design. Perspectives on the challenges and directions for future development in this exciting field are provided.

  4. [Analytical chemistry in works of Maria Skłodowska-Curie].

    PubMed

    Hulanicki, Adam

    2012-01-01

    Maria Skłodowska-Curie--a Nobel Prize winner in chemistry--the elements of learning of chemistry gained just by a dint of work of more than ten months in Warsaw in the Institute of Industry and Agriculture Museum. The Nobel Prize concerned a contribution to the progress of chemistry through the discovery of radium and polonium, separation of radium and study of properties of this amazing element. It was awarded for an extremely arduous work, during which the chemical reactions being the principles of analytical chemistry were realized. Unlike to a typical analytical procedure, an initial attempt here was the thousands of kilograms of uranium ore: pitchblende. The final effect was small amounts of new elements: polonium and radium. Both the knowledge and the intuition of the researcher let her have a triumph. The difficulties she experienced because the properties of the searched chemical elements could only be evaluated thanks to the knowledge on other chemical elements. A significant achievement was the determination of the samples by means of radioactivity measurement, which gave rise to radiochemical analytical methods. An extreme analytical precision was demanded in multiple processes of fractional crystallization and precipitation which finally led to the calculation of the atomic mass of radium.

  5. What are the Limitations of Enzymes in Synthetic Organic Chemistry?

    PubMed

    Reetz, Manfred T

    2016-12-01

    Enzymes have been used in organic chemistry and biotechnology for 100 years, but their widespread application has been prevented by a number of limitations, including the often-observed limited thermostability, narrow substrate scope, and low or wrong stereo- and/or regioselectivity. Directed evolution provides a means to address and generally solve these problems, especially since recent methodology development has made this protein engineering method faster, more efficient, and more reliable than in the past. This Darwinian approach to asymmetric catalysis has led to a number of industrial applications. Metabolic-pathway engineering, mutasynthesis, and fermentation are likewise enzyme-based techniques that enrich chemistry. This account outlines the scope, and particularly, the limitations, of biocatalysis. The complementary nature of enzymes and man-made catalysts is emphasized. © 2016 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Chemistry in microstructured reactors.

    PubMed

    Jähnisch, Klaus; Hessel, Volker; Löwe, Holger; Baerns, Manfred

    2004-01-16

    The application of microstructured reactors in the chemical process industry has gained significant importance in recent years. Companies that offer not only microstructured reactors, but also entire chemical process plants and services relating to them, are already in existence. In addition, many institutes and universities are active within this field, and process-engineering-oriented reviews and a specialized book are available. Microstructured systems can be applied with particular success in the investigation of highly exothermic and fast reactions. Often the presence of temperature-induced side reactions can be significantly reduced through isothermal operations. Although microstructured reaction techniques have been shown to optimize many synthetic procedures, they have not yet received the attention they deserve in organic chemistry. For this reason, this Review aims to address this by providing an overview of the chemistry in microstructured reactors, grouped into liquid-phase, gas-phase, and gas-liquid reactions.

  7. 2016 AMS Mario J. Molina Symposium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Renyi

    A named symposium to honor Dr. Mario J. Molina was held 10–14 January 2016, as part of the 96th American Meteorological Society (AMS) Annual Meeting in New Orleans, Louisiana. Dr. Molina first demonstrated that industrially produced chlorofluorocarbons (CFCs) decompose in the stratosphere and release chlorine atoms, leading to catalytic ozone destruction. His research in stratospheric chemistry was instrumental to the establishment of the 1987 United Nations Montreal Protocol to ban ozone-depleting substances worldwide. Dr. Molina’s contributions to preserving the planet Earth not only save the atmospheric ozone layer, but also protect the climate by reducing the emissions of greenhouse gases.more » He was awarded the 1995 Nobel Prize in Chemistry for his pioneering research in understanding the stratospheric ozone loss mechanism. In 2013, President Barack Obama announced Dr. Molina as a recipient of the Presidential Medal of Freedom. The 2016 AMS Molina Symposium honored Dr. Molina’s distinguished contributions to research related to atmospheric chemistry. The symposium contained an integrated theme related to atmospheric chemistry, climate, and policy. Dr. Molina delivered a keynote speech at the Symposium. The conference included invited keynote speeches and invited and contributed oral and poster sessions, and a banquet was held on Tuesday January 12, 2016. The symposium covered all aspects of atmospheric chemistry, with topics including (1) Stratospheric chemistry, (2) Tropospheric chemistry, (3) Aerosol nucleation, growth, and transformation, (4) Aerosol properties, (5) Megacity air pollution, and (6) Atmospheric chemistry laboratory, field, and modeling studies. This DOE project supported 14 scientists, including graduate students, post docs, junior research scientists, and non-tenured assistant professors to attend this symposium.« less

  8. Understanding the Cu-Zn brass alloys using a short-range-order cluster model: significance of specific compositions of industrial alloys

    PubMed Central

    Hong, H. L.; Wang, Q.; Dong, C.; Liaw, Peter K.

    2014-01-01

    Metallic alloys show complex chemistries that are not yet understood so far. It has been widely accepted that behind the composition selection lies a short-range-order mechanism for solid solutions. The present paper addresses this fundamental question by examining the face-centered-cubic Cu-Zn α-brasses. A new structural approach, the cluster-plus-glue-atom model, is introduced, which suits specifically for the description of short-range-order structures in disordered systems. Two types of formulas are pointed out, [Zn-Cu12]Zn1~6 and [Zn-Cu12](Zn,Cu)6, which explain the α-brasses listed in the American Society for Testing and Materials (ASTM) specifications. In these formulas, the bracketed parts represent the 1st-neighbor cluster, and each cluster is matched with one to six 2nd-neighbor Zn atoms or with six mixed (Zn,Cu) atoms. Such a cluster-based formulism describes the 1st- and 2nd-neighbor local atomic units where the solute and solvent interactions are ideally satisfied. The Cu-Ni industrial alloys are also explained, thus proving the universality of the cluster-formula approach in understanding the alloy selections. The revelation of the composition formulas for the Cu-(Zn,Ni) industrial alloys points to the common existence of simple composition rules behind seemingly complex chemistries of industrial alloys, thus offering a fundamental and practical method towards composition interpretations of all kinds of alloys. PMID:25399835

  9. Understanding the Cu-Zn brass alloys using a short-range-order cluster model: Significance of specific compositions of industrial alloys

    DOE PAGES

    Hong, H. L.; Wang, Q.; Dong, C.; ...

    2014-11-17

    Metallic alloys show complex chemistries that are not yet understood so far. It has been widely accepted that behind the composition selection lies a short-range-order mechanism for solid solutions. The present paper addresses this fundamental question by examining the face-centered-cubic Cu-Zn α-brasses. A new structural approach, the cluster-plus-glue-atom model, is introduced, which suits specifically for the description of short-range-order structures in disordered systems. Two types of formulas are pointed out, [Zn-Cu 12]Zn 1~6 and [Zn-Cu 12](Zn,Cu) 6, which explain the α-brasses listed in the American Society for Testing and Materials (ASTM) specifications. In these formulas, the bracketed parts represent themore » 1 st-neighbor cluster, and each cluster is matched with one to six 2 nd-neighbor Zn atoms or with six mixed (Zn,Cu) atoms. Such a cluster-based formulism describes the 1 st- and 2 nd-neighbor local atomic units where the solute and solvent interactions are ideally satisfied. The Cu-Ni industrial alloys are also explained, thus proving the universality of the cluster-formula approach in understanding the alloy selections. As a result, the revelation of the composition formulas for the Cu-(Zn,Ni) industrial alloys points to the common existence of simple composition rules behind seemingly complex chemistries of industrial alloys, thus offering a fundamental and practical method towards composition interpretations of all kinds of alloys.« less

  10. Microfluidics for food, agriculture and biosystems industries.

    PubMed

    Neethirajan, Suresh; Kobayashi, Isao; Nakajima, Mitsutoshi; Wu, Dan; Nandagopal, Saravanan; Lin, Francis

    2011-05-07

    Microfluidics, a rapidly emerging enabling technology has the potential to revolutionize food, agriculture and biosystems industries. Examples of potential applications of microfluidics in food industry include nano-particle encapsulation of fish oil, monitoring pathogens and toxins in food and water supplies, micro-nano-filtration for improving food quality, detection of antibiotics in dairy food products, and generation of novel food structures. In addition, microfluidics enables applications in agriculture and animal sciences such as nutrients monitoring and plant cells sorting for improving crop quality and production, effective delivery of biopesticides, simplified in vitro fertilization for animal breeding, animal health monitoring, vaccination and therapeutics. Lastly, microfluidics provides new approaches for bioenergy research. This paper synthesizes information of selected microfluidics-based applications for food, agriculture and biosystems industries. © The Royal Society of Chemistry 2011

  11. Traditional Chinese Biotechnology

    NASA Astrophysics Data System (ADS)

    Xu, Yan; Wang, Dong; Fan, Wen Lai; Mu, Xiao Qing; Chen, Jian

    The earliest industrial biotechnology originated in ancient China and developed into a vibrant industry in traditional Chinese liquor, rice wine, soy sauce, and vinegar. It is now a significant component of the Chinese economy valued annually at about 150 billion RMB. Although the production methods had existed and remained basically unchanged for centuries, modern developments in biotechnology and related fields in the last decades have greatly impacted on these industries and led to numerous technological innovations. In this chapter, the main biochemical processes and related technological innovations in traditional Chinese biotechnology are illustrated with recent advances in functional microbiology, microbial ecology, solid-state fermentation, enzymology, chemistry of impact flavor compounds, and improvements made to relevant traditional industrial facilities. Recent biotechnological advances in making Chinese liquor, rice wine, soy sauce, and vinegar are reviewed.

  12. Lowering industry firewalls: pre-competitive informatics initiatives in drug discovery.

    PubMed

    Barnes, Michael R; Harland, Lee; Foord, Steven M; Hall, Matthew D; Dix, Ian; Thomas, Scott; Williams-Jones, Bryn I; Brouwer, Cory R

    2009-09-01

    Pharmaceutical research and development is facing substantial challenges that have prompted the industry to shift funding from early- to late-stage projects. Among the effects is a major change in the attitude of many companies to their internal bioinformatics resources: the focus has moved from the vigorous pursuit of intellectual property towards exploration of pre-competitive cross-industry collaborations and engagement with the public domain. High-quality, open and accessible data are the foundation of pre-competitive research, and strong public-private partnerships have considerable potential to enhance public data resources, which would benefit everyone engaged in drug discovery. In this article, we discuss the background to these changes and propose new areas of collaboration in computational biology and chemistry between the public domain and the pharmaceutical industry.

  13. Chemistry of Carbon Nanotubes for Everyone

    ERIC Educational Resources Information Center

    Basu-Dutt, Sharmistha; Minus, Marilyn L.; Jain, Rahul; Nepal, Dhriti; Kumar, Satish

    2012-01-01

    Carbon nanotubes (CNTs) have the extraordinary potential to change our lives by improving existing products and enabling new ones. Current and future research and industrial workforce professionals are very likely to encounter some aspects of nanotechnology including CNT science and technology in their education or profession. The simple structure…

  14. Exploring application of cardanol from natural resource: Chemistry and products

    USDA-ARS?s Scientific Manuscript database

    Cardanol (cashew nut shell liquid, CNSL) is a renewable raw material derived from a byproduct of the cashew nut processing industry. First, two natural plasticizers derived from cardanol, cardanol acetate (CA) and epoxidated cardanol acetate (ECA), have been synthesized and characterized by 1HNMR an...

  15. Real World of Industrial Chemistry: Technology of the Rare Earths.

    ERIC Educational Resources Information Center

    Kremers, Howard E.

    1985-01-01

    The 17 rare earth elements account for one-fifth of the 83 naturally occurring elements and collectively rank as the 22nd most abundant "element." Properties of these elements (including their chemical similarity), their extraction from the earth, and their uses are discussed. (JN)

  16. MULTI-ANALYTE CHEMISTRY METHODS FOR PESTICIDES WHICH ARE ACETOLACTATE SYNTHASE (ALS) INHIBITORS IN SOIL

    EPA Science Inventory

    A joint EPA/state/industry working group has developed several multi-analyte methods to analyze soils for low ppb (parts per billion) levels of herbicides (such as sulfonylureas, imidazolinones, and sulfonamides) that are acetolactate synthase (ALS) inhibitors and may cause phyto...

  17. The Real World of Industrial Chemistry: The Use of Oxygen in the Treatment of Sewage.

    ERIC Educational Resources Information Center

    Cook, Gerhard A.; And Others

    1980-01-01

    Reviews the events leading up to the establishment of oxygen (rather than air) as an important component in the second stage treatment of municipal wastewater in sewage-disposal plants. Advantages, problems, and costs of using oxygen are discussed. (CS)

  18. Bibliography on carbohydrate synthesis. Selected works, 1861 - 1981

    NASA Technical Reports Server (NTRS)

    Dufour, P. A.

    1981-01-01

    International in scope, this bibliography cites 220 articles books, patents, and conference proceedings related to carbohydrate synthesis. The works are listed alphabetically by author in the following categories: (1) experimental and industrial chemistry; (2) space travel and feeding studies; (3) hardware; and (4) general reviews and progress.

  19. Technology for Improving Production, Economic Efficiency, Quality, and Sustainability in Peanut Production and Handling

    USDA-ARS?s Scientific Manuscript database

    USDA ARS National Peanut Research Laboratory has a very diverse scientific staff conducting research to address the needs of the United States peanut industry. Research is conducted in the fields of mycology, chemistry, biochemistry, molecular biology, breeding, agronomy, economics, and engineering....

  20. Technology for Improving Production, Economic Efficiency, Quality and Sustainability in Peanut Production and Handling

    USDA-ARS?s Scientific Manuscript database

    USDA ARS National Peanut Research Laboratory has a very diverse scientific staff conducting research to address the needs of the United States peanut industry. Research is conducted in the fields of mycology, chemistry, biochemistry, molecular biology, breeding, agronomy, economics, and engineering....

  1. Technology for improving production, economic efficiency, quality, and sustainability in peanut production and handling

    USDA-ARS?s Scientific Manuscript database

    USDA ARS National Peanut Research Laboratory has a very diverse scientific staff conducting research to address the needs of the United States peanut industry. Research is conducted in the fields of mycology, chemistry, biochemistry, molecular biology, breeding, agronomy, economics, and engineering....

  2. Occupational Listings Arranged by Cluster and Subject Matter Areas.

    ERIC Educational Resources Information Center

    Schwarz, Otto

    Approximately 850 occupations are listed under 27 occupational clusters. The Dictionary of Occupational Title (DOT) number is specified for occupations in the clusters of business training and distributive education, chemistry, general shop and industrial arts, home economics, foreign language, music, social studies, art, agriculture, physics, and…

  3. “Gold” Pressed Essential Oil: An Essay on the Volatile Fragment from Citrus Juice Industry By-Products Chemistry and Bioactivity

    PubMed Central

    Kapsaski-Kanelli, V. N.; Papachristos, D. P.; Myrtsi, E. D.; Koulocheri, S. D.

    2017-01-01

    Present essay explores the potentials of Citrus juice industry's by-products as alternative bioactive natural products resources. Four crude Cold Pressed Essential Oils (CPEOs), derived from orange, lemon, grapefruit, and mandarin, were studied. All CPEOs were subjected to water distillation, in order to obtain the volatile fragment, which was further fractionated with respect to distillation period in two parts, concluding to eight samples. These samples along with the four original CPEOs were assessed in relation to their phytochemical content and their repellent and larvicidal properties against Asian Tiger Mosquito. The volatiles recovery rates ranged from 74% to 88% of the CPEO. Limonene presented a significant increase in all samples ranging from 8% to 52% of the respective CPEO's content and peaked in mandarin's 2nd volatile fragment which comprised 97% of the essential oil. The refinement process presented clear impacts on both bioassays: a significant increase in larvicidal potency was observed, annotated best by the improvement by 1100% and 1300% of the grapefruit volatile fractions; repellence testing provided only one significant result, the decrease of landings by 50% as a response to mandarin's second volatile fraction. The applied methodology thus may be considered for the improvement of Citrus juice industry's by-products chemistry and bioactivity. PMID:29109957

  4. "Gold" Pressed Essential Oil: An Essay on the Volatile Fragment from Citrus Juice Industry By-Products Chemistry and Bioactivity.

    PubMed

    Kapsaski-Kanelli, V N; Evergetis, E; Michaelakis, A; Papachristos, D P; Myrtsi, E D; Koulocheri, S D; Haroutounian, S A

    2017-01-01

    Present essay explores the potentials of Citrus juice industry's by-products as alternative bioactive natural products resources. Four crude Cold Pressed Essential Oils (CPEOs), derived from orange, lemon, grapefruit, and mandarin, were studied. All CPEOs were subjected to water distillation, in order to obtain the volatile fragment, which was further fractionated with respect to distillation period in two parts, concluding to eight samples. These samples along with the four original CPEOs were assessed in relation to their phytochemical content and their repellent and larvicidal properties against Asian Tiger Mosquito. The volatiles recovery rates ranged from 74% to 88% of the CPEO. Limonene presented a significant increase in all samples ranging from 8% to 52% of the respective CPEO's content and peaked in mandarin's 2nd volatile fragment which comprised 97% of the essential oil. The refinement process presented clear impacts on both bioassays: a significant increase in larvicidal potency was observed, annotated best by the improvement by 1100% and 1300% of the grapefruit volatile fractions; repellence testing provided only one significant result, the decrease of landings by 50% as a response to mandarin's second volatile fraction. The applied methodology thus may be considered for the improvement of Citrus juice industry's by-products chemistry and bioactivity.

  5. Identification of major sources controlling groundwater chemistry from a hard rock terrain — A case study from Mettur taluk, Salem district, Tamil Nadu, India

    NASA Astrophysics Data System (ADS)

    Srinivasamoorthy, K.; Chidambaram, S.; Prasanna, M. V.; Vasanthavihar, M.; Peter, John; Anandhan, P.

    2008-02-01

    The study area Mettur forms an important industrial town situated NW of Salem district. The geology of the area is mainly composed of Archean crystalline metamorphic complexes. To identify the major process activated for controlling the groundwater chemistry an attempt has been made by collecting a total of 46 groundwater samples for two different seasons, viz., pre-monsoon and post-monsoon. The groundwater chemistry is dominated by silicate weathering and (Na + Mg) and (Cl + SO4) accounts of about 90% of cations and anions. The contribution of (Ca + Mg) and (Na + K) to total cations and HCO3 indicates the domination of silicate weathering as major sources for cations. The plot for Na to Cl indicates higher Cl in both seasons, derived from Anthropogenic (human) sources from fertilizer, road salt, human and animal waste, and industrial applications, minor representations of Na also indicates source from weathering of silicate-bearing minerals. The plot for Na/Cl to EC indicates Na released from silicate weathering process which is also supported by higher HCO3 values in both the seasons. Ion exchange process is also activated in the study area which is indicated by shifting to right in plot for Ca + Mg to SO4 + HCO3. The plot of Na-Cl to Ca + Mg-HCO3-SO4 confirms that Ca, Mg and Na concentrations in groundwater are derived from aquifer materials. Thermodynamic plot indicates that groundwater is in equilibrium with kaolinite, muscovite and chlorite minerals. Saturation index of silicate and carbonate minerals indicate oversaturation during pre-monsoon and undersaturation during post-monsoon, conforming dissolution and dilution process. In general, water chemistry is guided by complex weathering process, ion exchange along with influence of Cl ions from anthropogenic impact.

  6. BIGCHEM: Challenges and Opportunities for Big Data Analysis in Chemistry.

    PubMed

    Tetko, Igor V; Engkvist, Ola; Koch, Uwe; Reymond, Jean-Louis; Chen, Hongming

    2016-12-01

    The increasing volume of biomedical data in chemistry and life sciences requires the development of new methods and approaches for their handling. Here, we briefly discuss some challenges and opportunities of this fast growing area of research with a focus on those to be addressed within the BIGCHEM project. The article starts with a brief description of some available resources for "Big Data" in chemistry and a discussion of the importance of data quality. We then discuss challenges with visualization of millions of compounds by combining chemical and biological data, the expectations from mining the "Big Data" using advanced machine-learning methods, and their applications in polypharmacology prediction and target de-convolution in phenotypic screening. We show that the efficient exploration of billions of molecules requires the development of smart strategies. We also address the issue of secure information sharing without disclosing chemical structures, which is critical to enable bi-party or multi-party data sharing. Data sharing is important in the context of the recent trend of "open innovation" in pharmaceutical industry, which has led to not only more information sharing among academics and pharma industries but also the so-called "precompetitive" collaboration between pharma companies. At the end we highlight the importance of education in "Big Data" for further progress of this area. © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  7. GIRAFE, a campaign forecast tool for anthropogenic and biomass burning plumes

    NASA Astrophysics Data System (ADS)

    Fontaine, Alain; Mari, Céline; Drouin, Marc-Antoine; Lussac, Laure

    2015-04-01

    GIRAFE (reGIonal ReAl time Fire plumEs, http://girafe.pole-ether.fr, alain.fontaine@obs-mip.fr) is a forecast tool supported by the French atmospheric chemistry data centre Ether (CNES and CNRS), build on the lagrangian particle dispersion model FLEXPART coupled with ECMWF meteorological fields and emission inventories. GIRAFE was used during the CHARMEX campaign (Chemistry-Aerosol Mediterranean Experiment http://charmex.lsce.ipsl.fr) in order to provide daily 5-days plumes trajectory forecast over the Mediterranean Sea. For this field experiment, the lagrangian model was used to mimic carbon monoxide pollution plumes emitted either by anthropogenic or biomass burning emissions. Sources from major industrial areas as Fos-Berre or the Po valley were extracted from the MACC-TNO inventory. Biomass burning sources were estimated based on MODIS fire detection. Comparison with MACC and CHIMERE APIFLAME models revealed that GIRAFE followed pollution plumes from small and short-duration fires which were not captured by low resolution models. GIRAFE was used as a decision-making tool to schedule field campaign like airbone operations or balloons launching. Thanks to recent features, GIRAFE is able to read the ECCAD database (http://eccad.pole-ether.fr) inventories. Global inventories such as MACCITY and ECLIPSE will be used to predict CO plumes trajectories from major urban and industrial sources over West Africa for the DACCIWA campaign (Dynamic-Aerosol-Chemistry-Cloud interactions in West Africa).

  8. BIGCHEM: Challenges and Opportunities for Big Data Analysis in Chemistry

    PubMed Central

    Engkvist, Ola; Koch, Uwe; Reymond, Jean‐Louis; Chen, Hongming

    2016-01-01

    Abstract The increasing volume of biomedical data in chemistry and life sciences requires the development of new methods and approaches for their handling. Here, we briefly discuss some challenges and opportunities of this fast growing area of research with a focus on those to be addressed within the BIGCHEM project. The article starts with a brief description of some available resources for “Big Data” in chemistry and a discussion of the importance of data quality. We then discuss challenges with visualization of millions of compounds by combining chemical and biological data, the expectations from mining the “Big Data” using advanced machine‐learning methods, and their applications in polypharmacology prediction and target de‐convolution in phenotypic screening. We show that the efficient exploration of billions of molecules requires the development of smart strategies. We also address the issue of secure information sharing without disclosing chemical structures, which is critical to enable bi‐party or multi‐party data sharing. Data sharing is important in the context of the recent trend of “open innovation” in pharmaceutical industry, which has led to not only more information sharing among academics and pharma industries but also the so‐called “precompetitive” collaboration between pharma companies. At the end we highlight the importance of education in “Big Data” for further progress of this area. PMID:27464907

  9. Survey of whole air data from the second airborne Biomass Burning and Lightning Experiment using principal component analysis

    NASA Astrophysics Data System (ADS)

    Choi, Yunsoo; Elliott, Scott; Simpson, Isobel J.; Blake, Donald R.; Colman, Jonah J.; Dubey, Manvendra K.; Meinardi, Simone; Rowland, F. Sherwood; Shirai, Tomoko; Smith, Felisa A.

    2003-03-01

    Hydrocarbon and halocarbon measurements collected during the second airborne Biomass Burning and Lightning Experiment (BIBLE-B) were subjected to a principal component analysis (PCA), to test the capability for identifying intercorrelated compounds within a large whole air data set. The BIBLE expeditions have sought to quantify and understand the products of burning, electrical discharge, and general atmospheric chemical processes during flights arrayed along the western edge of the Pacific. Principal component analysis was found to offer a compact method for identifying the major modes of composition encountered in the regional whole air data set. Transecting the continental monsoon, urban and industrial tracers (e.g., combustion byproducts, chlorinated methanes and ethanes, xylenes, and longer chain alkanes) dominated the observed variability. Pentane enhancements reflected vehicular emissions. In general, ethyl and propyl nitrate groupings indicated oxidation under nitrogen oxide (NOx) rich conditions and hence city or lightning influences. Over the tropical ocean, methyl nitrate grouped with brominated compounds and sometimes with dimethyl sulfide and methyl iodide. Biomass burning signatures were observed during flights over the Australian continent. Strong indications of wetland anaerobics (methane) or liquefied petroleum gas leakage (propane) were conspicuous by their absence. When all flights were considered together, sources attributable to human activity emerged as the most important. We suggest that factor reductions in general and PCA in particular may soon play a vital role in the analysis of regional whole air data sets, as a complement to more familiar methods.

  10. Synthesis and Evaluation of Chirally Defined Side Chain Variants of 7-Chloro-4-Aminoquinoline To Overcome Drug Resistance in Malaria Chemotherapy

    PubMed Central

    Dola, Vasantha Rao; Soni, Awakash; Agarwal, Pooja; Ahmad, Hafsa; Raju, Kanumuri Siva Rama; Rashid, Mamunur; Wahajuddin, Muhammad; Srivastava, Kumkum; Haq, W.; Dwivedi, A. K.; Puri, S. K.

    2016-01-01

    ABSTRACT A novel 4-aminoquinoline derivative [(S)-7-chloro-N-(4-methyl-1-(4-methylpiperazin-1-yl)pentan-2-yl)-quinolin-4-amine triphosphate] exhibiting curative activity against chloroquine-resistant malaria parasites has been identified for preclinical development as a blood schizonticidal agent. The lead molecule selected after detailed structure-activity relationship (SAR) studies has good solid-state properties and promising activity against in vitro and in vivo experimental malaria models. The in vitro absorption, distribution, metabolism, and excretion (ADME) parameters indicate a favorable drug-like profile. PMID:27956423

  11. Structure and Dynamics of Interfaces: Drops and Films

    NASA Technical Reports Server (NTRS)

    Mann, J. Adin, Jr.; Mann, Elizabeth K.; Meyer, William V.; Neumann, A. Wilhelm; Tavana, Hossein

    2015-01-01

    We aim to acquire measurements of the structure and dynamics of certain liquid-fluid interfaces using an ensemble of techniques in collaboration: (1) Total internal reflection (TIR) Surface light scattering spectroscopy (SLSS), (2) Brewster angle microscopy (BAM), and (3) Drop-shape analysis. SLSS and BAM can be done on a shared interfacial footprint. Results using a 50-50 mixture of pentane-isohexane, which extends the range of NASA's Confined Vapor Bubble (CVB) experiment, yield surface tension results that differ from the expected Langmuir Fit. These results were confirmed using both the SLSS and drop-shape analysis approaches.

  12. Reliable method for determination of the velocity of a sinker in a high-pressure falling body type viscometer

    NASA Astrophysics Data System (ADS)

    Dindar, Cigdem; Kiran, Erdogan

    2002-10-01

    We present a new sensor configuration and data reduction process to improve the accuracy and reliability of determining the terminal velocity of a falling sinker in falling body type viscometers. This procedure is based on the use of multiple linear variable differential transformer sensors and precise mapping of the sensor signal and position along with the time of fall which is then converted to distance versus fall time along the complete fall path. The method and its use in determination of high-pressure viscosity of n-pentane and carbon dioxide are described.

  13. Four new 6-oxy purine alkaloids from the South China Sea sponge, Haliclona cymaeformis

    NASA Astrophysics Data System (ADS)

    Chen, Min; Wu, Xudong; Shen, Nanxing; Wang, Changyun

    2017-12-01

    In this study, the chemical analysis of the marine sponge spieces, Haliclona cymaeformis, collected from the South China Sea was carried out, Two pairs of regioisomers of alkyl substitutional 6-oxy purine alkaloids ( 1a/ 1b and 2a/ 2b) were isolated. All of them possess two structural moieties, a 6-oxy purine nucleus and a pentan-2-one or hexan-2-one alkyl chain. Among them, 1a and 2a are the major N-9-substitutional regioisomers, and 1b and 2b are the minor N-7-substitutional regioisomers.

  14. Achieving continuous manufacturing: technologies and approaches for synthesis, workup, and isolation of drug substance. May 20-21, 2014 Continuous Manufacturing Symposium.

    PubMed

    Baxendale, Ian R; Braatz, Richard D; Hodnett, Benjamin K; Jensen, Klavs F; Johnson, Martin D; Sharratt, Paul; Sherlock, Jon-Paul; Florence, Alastair J

    2015-03-01

    This whitepaper highlights current challenges and opportunities associated with continuous synthesis, workup, and crystallization of active pharmaceutical ingredients (drug substances). We describe the technologies and requirements at each stage and emphasize the different considerations for developing continuous processes compared with batch. In addition to the specific sequence of operations required to deliver the necessary chemical and physical transformations for continuous drug substance manufacture, consideration is also given to how adoption of continuous technologies may impact different manufacturing stages in development from discovery, process development, through scale-up and into full scale production. The impact of continuous manufacture on drug substance quality and the associated challenges for control and for process safety are also emphasized. In addition to the technology and operational considerations necessary for the adoption of continuous manufacturing (CM), this whitepaper also addresses the cultural, as well as skills and training, challenges that will need to be met by support from organizations in order to accommodate the new work flows. Specific action items for industry leaders are: Develop flow chemistry toolboxes, exploiting the advantages of flow processing and including highly selective chemistries that allow use of simple and effective continuous workup technologies. Availability of modular or plug and play type equipment especially for workup to assist in straightforward deployment in the laboratory. As with learning from other industries, standardization is highly desirable and will require cooperation across industry and academia to develop and implement. Implement and exploit process analytical technologies (PAT) for real-time dynamic control of continuous processes. Develop modeling and simulation techniques to support continuous process development and control. Progress is required in multiphase systems such as crystallization. Involve all parts of the organization from discovery, research and development, and manufacturing in the implementation of CM. Engage with academia to develop the training provision to support the skills base for CM, particularly in flow chemistry, physical chemistry, and chemical engineering skills at the chemistry-process interface. Promote and encourage publication and dissemination of examples of CM across the sector to demonstrate capability, engage with regulatory comment, and establish benchmarks for performance and highlight challenges. Develop the economic case for CM of drug substance. This will involve various stakeholders at project and business level, however establishing the critical economic drivers is critical to driving the transformation in manufacturing. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  15. AutoClickChem: click chemistry in silico.

    PubMed

    Durrant, Jacob D; McCammon, J Andrew

    2012-01-01

    Academic researchers and many in industry often lack the financial resources available to scientists working in "big pharma." High costs include those associated with high-throughput screening and chemical synthesis. In order to address these challenges, many researchers have in part turned to alternate methodologies. Virtual screening, for example, often substitutes for high-throughput screening, and click chemistry ensures that chemical synthesis is fast, cheap, and comparatively easy. Though both in silico screening and click chemistry seek to make drug discovery more feasible, it is not yet routine to couple these two methodologies. We here present a novel computer algorithm, called AutoClickChem, capable of performing many click-chemistry reactions in silico. AutoClickChem can be used to produce large combinatorial libraries of compound models for use in virtual screens. As the compounds of these libraries are constructed according to the reactions of click chemistry, they can be easily synthesized for subsequent testing in biochemical assays. Additionally, in silico modeling of click-chemistry products may prove useful in rational drug design and drug optimization. AutoClickChem is based on the pymolecule toolbox, a framework that may facilitate the development of future python-based programs that require the manipulation of molecular models. Both the pymolecule toolbox and AutoClickChem are released under the GNU General Public License version 3 and are available for download from http://autoclickchem.ucsd.edu.

  16. AutoClickChem: Click Chemistry in Silico

    PubMed Central

    Durrant, Jacob D.; McCammon, J. Andrew

    2012-01-01

    Academic researchers and many in industry often lack the financial resources available to scientists working in “big pharma.” High costs include those associated with high-throughput screening and chemical synthesis. In order to address these challenges, many researchers have in part turned to alternate methodologies. Virtual screening, for example, often substitutes for high-throughput screening, and click chemistry ensures that chemical synthesis is fast, cheap, and comparatively easy. Though both in silico screening and click chemistry seek to make drug discovery more feasible, it is not yet routine to couple these two methodologies. We here present a novel computer algorithm, called AutoClickChem, capable of performing many click-chemistry reactions in silico. AutoClickChem can be used to produce large combinatorial libraries of compound models for use in virtual screens. As the compounds of these libraries are constructed according to the reactions of click chemistry, they can be easily synthesized for subsequent testing in biochemical assays. Additionally, in silico modeling of click-chemistry products may prove useful in rational drug design and drug optimization. AutoClickChem is based on the pymolecule toolbox, a framework that may facilitate the development of future python-based programs that require the manipulation of molecular models. Both the pymolecule toolbox and AutoClickChem are released under the GNU General Public License version 3 and are available for download from http://autoclickchem.ucsd.edu. PMID:22438795

  17. A Brief History of the Most Remarkable Numbers "e," "i" and "?" in Mathematical Sciences with Applications

    ERIC Educational Resources Information Center

    Debnath, Lokenath

    2015-01-01

    This paper deals with a brief history of the most remarkable Euler numbers "e,"?"i"?and?"?" in mathematical sciences. Included are many properties of the constants "e,"?"i"?and?"?" and their applications in algebra, geometry, physics, chemistry, ecology, business and industry. Special…

  18. Berkeley Lab Wins Seven 2015 R&D 100 Awards | Berkeley Lab

    Science.gov Websites

    products from industry, academia, and government-sponsored research, ranging from chemistry to materials to problems in metrology techniques: the quantitative characterization of the imaging instrumentation Computational Research Division led the development of the technology. Sensor Integrated with Recombinant and

  19. Real-Time Monitoring of Heterogeneous Catalysis with Mass Spectrometry

    ERIC Educational Resources Information Center

    Young, Mark A.

    2009-01-01

    Heterogeneous, gas-solid processes constitute an important class of catalytic reactions that play a key role in a variety of applications, such as industrial processing and environmental controls. Heterogeneous catalytic chemistry can be demonstrated in a simple heated flow reactor containing a fragment of the catalytic converter from a vehicular…

  20. High-Resolution Solid-State NMR Spectroscopy: Characterization of Polymorphism in Cimetidine, a Pharmaceutical Compound

    ERIC Educational Resources Information Center

    Pacilio, Julia E.; Tokarski, John T.; Quiñones, Rosalynn; Iuliucci, Robbie J.

    2014-01-01

    High-resolution solid-state NMR (SSNMR) spectroscopy has many advantages as a tool to characterize solid-phase material that finds applications in polymer chemistry, nanotechnology, materials science, biomolecular structure determination, and others, including the pharmaceutical industry. The technology associated with achieving high resolution…

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