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Sample records for spontaneous deposition methanol

  1. Palladium deposits spontaneously grown on nickel foam for electro-catalyzing methanol oxidation: Effect of precursors

    NASA Astrophysics Data System (ADS)

    Niu, Xiangheng; Zhao, Hongli; Lan, Minbo

    2016-02-01

    Methanol, a high-energy substance, is widely used for green fuel cells. However, the sluggish electrochemical methanol oxidation reaction (MOR) on state-of-the-art catalysts still requires for exploring high-performance and low-cost materials to further promote the reaction kinetics at low overpotentials. Here we carried out the first electrocatalytic comparison study of two Ni foam-supported Pd nanomaterials (Pd-2-Ni and Pd-4-Ni, respectively), obtained through the spontaneous galvanic replacement of Ni with different palladic precursors ([PdCl4]2- and [PdCl6]2-, respectively), toward MOR. With replacement, Pd deposits with discrepant arrangements and coverages were grown on the porous Ni support. Compared to commercial Pd/C, both Pd-2-Ni and Pd-4-Ni exhibited better mass activity and catalytic durability for MOR in alkaline media. More interestingly, different palladic precursors made a significant effect on the catalytic performance of the Ni foam-supported Pd deposits. In Pd-4-Ni, the 2:1 stoichiometric replacement of Ni with [PdCl6]2- enabled the incompact arrangement of Pd structures, with more exposure of Ni atoms adjoined to Pd atoms on the catalytic interface compared to Pd-2-Ni. As a result, with the favorable Ni-neighbor-Pd regime and the higher utilization efficiency of Pd atoms, the synthesized Pd-4-Ni catalyst provided a mass activity of approximately 1.5 times higher than Pd-2-Ni toward MOR.

  2. Atmospheric deposition of methanol over the Atlantic Ocean.

    PubMed

    Yang, Mingxi; Nightingale, Philip D; Beale, Rachael; Liss, Peter S; Blomquist, Byron; Fairall, Christopher

    2013-12-10

    In the troposphere, methanol (CH3OH) is present ubiquitously and second in abundance among organic gases after methane. In the surface ocean, methanol represents a supply of energy and carbon for marine microbes. Here we report direct measurements of air-sea methanol transfer along a ∼10,000-km north-south transect of the Atlantic. The flux of methanol was consistently from the atmosphere to the ocean. Constrained by the aerodynamic limit and measured rate of air-sea sensible heat exchange, methanol transfer resembles a one-way depositional process, which suggests dissolved methanol concentrations near the water surface that are lower than what were measured at ∼5 m depth, for reasons currently unknown. We estimate the global oceanic uptake of methanol and examine the lifetimes of this compound in the lower atmosphere and upper ocean with respect to gas exchange. We also constrain the molecular diffusional resistance above the ocean surface-an important term for improving air-sea gas exchange models.

  3. Atmospheric deposition of methanol over the Atlantic Ocean

    PubMed Central

    Yang, Mingxi; Nightingale, Philip D.; Beale, Rachael; Liss, Peter S.; Blomquist, Byron; Fairall, Christopher

    2013-01-01

    In the troposphere, methanol (CH3OH) is present ubiquitously and second in abundance among organic gases after methane. In the surface ocean, methanol represents a supply of energy and carbon for marine microbes. Here we report direct measurements of air–sea methanol transfer along a ∼10,000-km north–south transect of the Atlantic. The flux of methanol was consistently from the atmosphere to the ocean. Constrained by the aerodynamic limit and measured rate of air–sea sensible heat exchange, methanol transfer resembles a one-way depositional process, which suggests dissolved methanol concentrations near the water surface that are lower than what were measured at ∼5 m depth, for reasons currently unknown. We estimate the global oceanic uptake of methanol and examine the lifetimes of this compound in the lower atmosphere and upper ocean with respect to gas exchange. We also constrain the molecular diffusional resistance above the ocean surface—an important term for improving air–sea gas exchange models. PMID:24277830

  4. Palladium catalysts synthesized by atomic layer deposition for methanol decomposition.

    SciTech Connect

    Elam, J. W.; Feng, H.; Stair, P. C.; Libera, J. A.; Setthapun, W.; Northwestern Univ.

    2010-05-25

    Atomic layer deposition (ALD) palladium films were deposited at 200 C on various ALD metal oxide surfaces using sequential exposures to Pd(II) hexafluoroacetylacetonate (Pd(hfac)2) and formalin. In situ quartz crystal microbalance measurements as well as ex situ measurements performed on planar substrates revealed that the Pd growth begins with a relatively slow nucleation process and accelerates once an adequate amount of Pd has deposited on the surface. Furthermore, the Pd nucleation is faster on ALD ZnO surfaces compared to ALD Al2O3 surfaces. ALD was utilized to synthesize highly dispersed, uniform Pd nanoparticles (1 to 2 nm in diameter) on ALD ZnO and Al2O3 coated mesoporous silica gel, and the catalytic performances of these samples were compared in the methanol decomposition reaction. The ALD Pd-Al2O3 showed high activity and hydrogen selectivity at relatively low temperatures while the ALD Pd-ZnO showed very low activity as well as quick deactivation. In situ extended X-ray absorption fine structure (EXAFS) measurement revealed that the Pd supported on ZnO 'dissolves' into the substrate during the methanol decomposition reaction which accounts for the gradual disappearance of its catalytic activity. By applying one cycle of ALD Al2O3 on top of the Pd-ZnO catalyst, the activity was enhanced and the catalyst deactivation was mitigated. This Al2O3 overcoating method stabilizes the Pd-ZnO and effectively prevents the dissolution of Pd into the ZnO substrate.

  5. Methanol

    Integrated Risk Information System (IRIS)

    Methanol ; CASRN 67 - 56 - 1 Human health assessment information on a chemical substance is included in IRIS only after a comprehensive review of toxicity data by U.S . EPA health scientists from several program offices , regional offices , and the Office of Research and Development . Sections I ( H

  6. Spontaneous metal deposition from organic solutions for electronic materials applications

    NASA Astrophysics Data System (ADS)

    Fang, Rui

    Electrochemical deposition (ECD) has been used widely in the electronics industry. A novel "galvanic deposition" process was used for spontaneous and selective ECD of metal from organic solutions in contrast to the more conventional aqueous media. The more noble metal ions loaded in the organic solution are reduced and deposited onto the less noble metal substrate, which is simultaneously dissolved into the organic. Cu and Pd seed layers have been successfully deposited from organic solutions onto patterned and unpatterned pure aluminum and Al(0.5wt%Cu) thin films using this immersion displacement process. The Cu and Pd deposits were effectively used as catalytic sites for subsequent conventional electroless or electrolytic copper deposition. Further studies were performed to modify and optimize the organic deposition solution composition. These modified organic solutions could be used to deposit nearly continuous copper films on both unpatterned and patterned aluminum substrates. A patent disclosure on the modified organic deposition process was made to the University of Missouri and will be officially filed with the U.S. Patent Office. The EIS technique was one method used to characterize these high resistivity organic media. The organic solution resistivities were determined to be in the range of ˜108 O-cm but decreased to ˜10 6 O-cm with the addition of some modifying additives. Pd and Cu deposition have also been accomplished on various blanket and patterned Ti, TiN, Ta, and TaN barrier films. Some pre-treatment or in-situ etching in combination with ultrasonic or intensive mechanical agitation was necessary to activate the surface and enhance the metal deposition reaction. After seeding, continuous copper films were built up using a conventional electroless or electroplating process.

  7. Splitting methanol on ultra-thin MgO(100) films deposited on a Mo substrate.

    PubMed

    Song, Zhenjun; Xu, Hu

    2017-03-08

    The dissociation reaction of methanol on metal-supported MgO(100) films has been studied by employing density functional theory calculations. As far as we know, the dissociation of a single methanol molecule over inert oxide insulators such as MgO has not yet been successfully realized without the introduction of defects or low coordinated atoms. By depositing ultra-thin oxide films on a Mo substrate, we have successfully proposed the dissociative state of methanol. The dissociation reaction is energetically exothermic and nearly barrierless. The lattice mismatch between ultra-thin MgO(100) films and metal substrates plays a crucial role in the heterolytic dissociation of adsorbates, while the electronic effect of the Mo(100) substrate plays a non-ignorable role in the homolytic dissociation of methanol. The metal-supported ultra-thin oxide films studied herein provide a versatile approach to enhance the surface reaction activity and properties of oxides.

  8. A spontaneous and passive waste-management device (PWMD) for a micro direct methanol fuel cell

    NASA Astrophysics Data System (ADS)

    Chuang, Yun-Ju; Chieng, Ching-Chang; Pan, Chin; Luo, Shih-Jin; Tseng, Fan-Gang

    2007-05-01

    This paper introduces a passive waste-management device (PWMD) for a micro direct methanol fuel cell to exhale CO2 gas and to gather and transport water and methanol residue during operation. It passively employs condensation, temperature gradient, surface tension gradient and droplet coalescence to accumulate liquid, separate liquid and gas, and transport droplets without the need of external power. CO2 gas can be breathed out through hydrophobic micro holes with the assistance of buoyancy force while water/methanol vapor is condensing into droplets, coalescing with smaller droplets and is transported toward a cooler and more hydrophilic waste tank through wettability gradient. The wettability gradient is prepared by diffusion-controlled silanization with a gradient from 117° to 28° and is radial toward the outer boundary, which can drive droplets down to 1 µl with a speed of up to 20 mm s-1. With the assistance of coalescence along with the wettability gradient, the condensed water droplets can reach a double speed of 40 mm s-1. The maximum water removal rate of the PWMD can approach 6.134 µl s-1 cm-2, which is at least one order of magnitude higher than the demand of a standard µDMFC with power generation ability of 100 mW cm-2.

  9. Investigations of a platinum-ruthenium/carbon nanotube catalyst formed by a two-step spontaneous deposition method

    NASA Astrophysics Data System (ADS)

    Chang, Wei-Chin; Nguyen, Minh Toan

    Platinum (Pt) is a popular catalyst for hydrogen oxidation on the anode side of solid polymer fuel cells (SPFC). It increases the electrode activity, which catalyzes the reaction of the fuel cell. There are two methods commonly used to produce hydrogen for SPFC: fuel reforming and methanol decomposition. Both of these methods produce carbon monoxide, which is considered to be a poison for SPFC because it deactivates Pt easily. Adding ruthenium (Ru) to a Pt catalyst is an efficient way to improve the inhibition of carbon monoxide (CO) formation and reduce the Pt loading requirement. This study introduces a method to synthesize a bimetal catalyst that is suitable for SPFC. To improve the electrocatalyst activity, a new process with two spontaneous deposition steps is adopted. In the first step, Ru is deposited on the wall of carbon nanotubes (CNTs) to obtain Ru/CNTs. Pt is then added in the second deposition step to form Pt-Ru/CNTs. The morphology and microstructure of catalysts are characterized with microscopes, and the performance of membrane electrode assembly is evaluated by cyclic voltammetry method. Experimental results have proved that even with a lower Pt loading, this home-brewed bimetal catalyst performs a compatible electrocatalytic activity, and is capable of resisting attack from CO when a syngas (H 2 + 20 ppm CO) is provided.

  10. Beta amyloid deposition and neurofibrillary tangles spontaneously occur in the brains of captive cheetahs (Acinonyx jubatus).

    PubMed

    Serizawa, S; Chambers, J K; Une, Y

    2012-03-01

    Alzheimer disease is a dementing disorder characterized pathologically by Aβ deposition, neurofibrillary tangles, and neuronal loss. Although aged animals of many species spontaneously develop Aβ deposits, only 2 species (chimpanzee and wolverine) have been reported to develop Aβ deposits and neurofibrillary tangles in the same individual. Here, the authors demonstrate the spontaneous occurrence of Aβ deposits and neurofibrillary tangles in captive cheetahs (Acinonyx jubatus). Among 22 cheetahs examined in this study, Aβ deposits were observed in 13. Immunostaining (AT8) revealed abnormal intracellular tau immunoreactivity in 10 of the cheetahs with Aβ deposits, and they were mainly distributed in the parahippocampal cortex and CA1 in a fashion similar to that in human patients with Alzheimer disease. Ultrastructurally, bundles of straight filaments filled the neuronal somata and axons, consistent with tangles. Interestingly, 2 of the cheetahs with the most severe abnormal tau immunoreactivity showed clinical cognitive dysfunction. The authors conclude that cheetahs spontaneously develop age-related neurodegenerative disease with pathologic changes similar to Alzheimer disease.

  11. Tuneable stability of nanoemulsions fabricated using spontaneous emulsification by biopolymer electrostatic deposition.

    PubMed

    Saberi, Amir Hossein; Zeeb, Benjamin; Weiss, Jochen; McClements, David Julian

    2015-10-01

    Nanoemulsions can be formed spontaneously from surfactant-oil-water systems using low energy methods. In this work, we showed that the droplets in oil-in-water nanoemulsions fabricated by spontaneous emulsification could be coated with an anionic biopolymer (beet pectin) using electrostatic deposition. Nanoemulsions were formed by titrating oil (medium chain triglycerides) and surfactant (polyoxyethylene sorbitan monostearate+lauric arginate) mixtures into an aqueous solution (10 mM citrate buffer, pH 4). Lauric arginate was used to generate a positive charge on the droplet surfaces, thereby enabling subsequent electrostatic deposition of anionic pectin. Extensive droplet aggregation occurred when intermediate pectin concentrations were used due to bridging flocculation. However, stable anionic pectin-coated lipid droplets could be formed at high pectin concentrations. These results demonstrate the possibility of tailoring the functionality of lipid nanodroplets produced by spontaneous emulsification. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Breath-by-breath measurement of particle deposition in the lung of spontaneously breathing rats.

    PubMed

    Karrasch, S; Eder, G; Bolle, I; Tsuda, A; Schulz, H

    2009-10-01

    A number of deposition models for humans, as well as experimental animals, have been described. However, no breath-by-breath deposition measurement in rats has been reported to date. The objective of this study is to determine lung deposition of micrometer-sized particles as a function of breathing parameters in the adult rat lung. A new aerosol photometry system was designed to measure deposition of nonhygroscopic, 2-mum sebacate particles in anesthetized, intubated, and spontaneously breathing 90-day-old Wistar-Kyoto rats placed in a size-adjusted body plethysmograph box. Instrumental dead space of the system was minimized down to 310 microl (i.e., approximately 20% of respiratory dead space). The system allows continuous monitoring of particle concentration in the respired volume. Breathing parameters, such as respiratory rate (f), tidal volume (Vt), as well as inspiration/expiration times, were also monitored at different levels of anesthesia. The results showed that Vt typically varied between 1.5 and 4.0 ml for regular breathing and between 4.0 and 10.0 ml for single-sigh breaths; f ranged from 40 to 200 breaths/min. Corresponding deposition values varied between 5 and 50%, depending on breath-by-breath breathing patterns. The best fit of deposition (D) was achieved by a bilinear function of Vt and f and found to be D = 11.0 - 0.09.f + 3.75.Vt. We conclude that our approach provides more realistic conditions for the measurement of deposition than conventional models using ventilated animals and allows us to analyze the correlation between breath-specific deposition and spontaneous breathing patterns.

  13. Bimetallic Nickel/Ruthenium Catalysts Synthesized by Atomic Layer Deposition for Low-Temperature Direct Methanol Solid Oxide Fuel Cells.

    PubMed

    Jeong, Heonjae; Kim, Jun Woo; Park, Joonsuk; An, Jihwan; Lee, Tonghun; Prinz, Fritz B; Shim, Joon Hyung

    2016-11-09

    Nickel and ruthenium bimetallic catalysts were heterogeneously synthesized via atomic layer deposition (ALD) for use as the anode of direct methanol solid oxide fuel cells (DMSOFCs) operating in a low-temperature range. The presence of highly dispersed ALD Ru islands over a porous Ni mesh was confirmed, and the Ni/ALD Ru anode microstructure was observed. Fuel cell tests were conducted using Ni-only and Ni/ALD Ru anodes with approximately 350 μm thick gadolinium-doped ceria electrolytes and platinum cathodes. The performance of fuel cells was assessed using pure methanol at operating temperatures of 300-400 °C. Micromorphological changes of the anode after cell operation were investigated, and the content of adsorbed carbon on the anode side of the operated samples was measured. The difference in the maximum power density between samples utilizing Ni/ALD Ru and Pt/ALD Ru, the latter being the best catalyst for direct methanol fuel cells, was observed to be less than 7% at 300 °C and 30% at 350 °C. The improved electrochemical activity of the Ni/ALD Ru anode compared to that of the Ni-only anode, along with the reduction of the number of catalytically active sites due to agglomeration of Ni and carbon formation on the Ni surface as compared to Pt, explains this decent performance.

  14. Spontaneous formation of hierarchical wrinkles in Cr films deposited on silicone oil drops with constrained edges.

    PubMed

    Yu, Sen-Jiang; Zhang, Yong-Ju; Zhou, Hong; Chen, Miao-Gen; Zhang, Xiao-Fei; Jiao, Zhi-Wei; Si, Ping-Zhan

    2013-10-01

    We report on the spontaneous formation of hierarchical wrinkling patterns in Cr films deposited on silicone oil drops with constrained edges. The appearance of the wrinkling patterns is strongly dependent on the film thickness and the size of the silicone oil drop. Because the Cr film at the drop edge is constrained due to the strong adhesion between the film and the glass surface, the wrinkle wavelength merely depends on the distance starting from the drop edge. When the distance increases, the wavelength increases quickly first, and then it slows down gradually in compliance with a simple power law. The evolution of the wrinkle amplitude is similar to that of the wavelength, but it is also closely related to the film thickness and the oil drop size. Based on the fact that the silicone oil is polymerized to form an elastic layer during deposition, the formation and evolution of the hierarchical wrinkling patterns have been analyzed in detail.

  15. Spontaneous deposition of gold nanoparticle nanocomposite on polymer surfaces through sol-gel chemistry

    NASA Astrophysics Data System (ADS)

    Choi, Yong-Jae; Chiu, Chi-Kai; Luo, Tzy-Jiun M.

    2011-01-01

    A aminosilica nanocomposite layer containing a monolayer of gold nanoparticles (d = 18-22 nm) with a well-defined spacing was spontaneously deposited on an unmodified polystyrene surface via a sol-gel reaction when the reduction reaction was carried out under 1:8 molar ratio (gold(III):aminosilane). The amount of aminosilica and spacing between gold nanoparticles were found to be a function of the aminosilane:water molar ratio, which contributes to the plasmonic property of the films with its absorption wavelength ranging between 701 and 548 nm. Furthermore, the nanocomposite film that consists of a monolayer of nanoparticles in aminosilica has also been deposited on the surface of polystyrene beads. This core-shell structure was found capable of storing electrostatic charges and forming a well-separated 2D array.

  16. The synthesis of methanol and the reverse water-gas shift reaction over Zn-deposited Cu(100) and Cu(110) surfaces: comparison with Zn/Cu(111)

    NASA Astrophysics Data System (ADS)

    Nakamura, I.; Fujitani, T.; Uchijima, T.; Nakamura, J.

    1998-03-01

    The catalytic activity of Zn vapor-deposited Cu(100) and Cu(110) surfaces for methanol synthesis by the hydrogenation of CO 2 and the reverse water-gas shift reaction were studied using an XPS apparatus combined with a high-pressure flow reactor (18 atm). At a reaction temperature of 523 K, no promotional effect of Zn was observed for the methanol synthesis on both Zn/Cu(100) and Zn/Cu(110). The results were quite different from those for Zn/Cu(111), on which a significant promotion of methanol synthesis activity appeared to be due to the deposition of Zn, indicating that the promotional effect of Zn was sensitive to the surface structure of Cu. However, hysteresis was observed in the catalytic activity for methanol synthesis over the Zn/Cu(110) surface upon heating above 543 K in the reaction mixture. The activity became twice that measured before heating, which was close to the methanol synthesis activity of Zn/Cu(111) at the same Zn coverage. On the other hand, no such hysteresis was observed for the reverse water-gas shift reaction on Zn/Cu(110), indicating that the active site for methanol synthesis was not identical to that for the reverse water-gas shift reaction. In the post-reaction surface analysis, formate species was detected on both Zn/Cu(100) and Zn/Cu(110), whose coverage increased with increasing Zn coverage at 0< ΘZn<0.2. No correlation between the formate coverage and the methanol synthesis activity was obtained, which was in contrast to the results for Zn/Cu(111). Thus, the structure sensitivity observed in the catalytic activity of methanol synthesis over Zn-deposited Cu surfaces is ascribed to the significant difference in the reactivity of the formate intermediate.

  17. Method of plasma enhanced chemical vapor deposition of diamond using methanol-based solutions

    NASA Technical Reports Server (NTRS)

    Tzeng, Yonhua (Inventor)

    2009-01-01

    Briefly described, methods of forming diamond are described. A representative method, among others, includes: providing a substrate in a reaction chamber in a non-magnetic-field microwave plasma system; introducing, in the absence of a gas stream, a liquid precursor substantially free of water and containing methanol and at least one carbon and oxygen containing compound having a carbon to oxygen ratio greater than one, into an inlet of the reaction chamber; vaporizing the liquid precursor; and subjecting the vaporized precursor, in the absence of a carrier gas and in the absence in a reactive gas, to a plasma under conditions effective to disassociate the vaporized precursor and promote diamond growth on the substrate in a pressure range from about 70 to 130 Torr.

  18. Spontaneous wrinkling of soft matter by energetic deposition of Cr and Au

    NASA Astrophysics Data System (ADS)

    Teixeira, F. S.; Araújo, W. W. R.; Salvadori, M. C.

    2016-04-01

    Wrinkling of stiff thin films deposited on compliant substrates is an effect that has been broadly investigated. However, wrinkling consequent to metal ion implantation has been less studied. In the work described here, we have explored the sub-micron wrinkling phenomena that spontaneously occur when metal ions (Au and Cr) are implanted with energy of a few tens of electron volts (49 eV for Au and 72 eV for Cr) into a compliant material (PDMS). This very low energy ion implantation was performed using a Filtered Cathodic Vacuum Arc technique, a process often referred to as energetic deposition or energetic condensation. For comparison, Au and Cr depositions with similar doses were also done using a sputtering technique (with lower particle energy of approximately 2 eV), and no wrinkle formation was then observed. In this way, we can discuss the role of ion energy in wrinkle formation. Depth profiles of the implanted material were calculated using the Tridyn computer simulation code for each metal, for several implantation doses. UV-vis absorption spectroscopy analysis confirmed the presence of metal nanoparticles. Atomic Force Microscopy imaging with spectral processing was used to compare the wrinkle morphology for each case investigated.

  19. Particle deposition in spontaneously hypertensive rats exposed via whole-body inhalation: measured and estimated dose.

    PubMed

    Wichers, Lindsay B; Rowan, William H; Nolan, Julianne P; Ledbetter, Allen D; McGee, John K; Costa, Daniel L; Watkinson, William P

    2006-10-01

    A plethora of epidemiological studies have shown that exposure to elevated levels of ambient particulate matter (PM) can lead to adverse health outcomes, including cardiopulmonary-related mortality. Subsequent animal toxicological studies have attempted to mimic these cardiovascular and respiratory responses, in order to better understand underlying mechanisms. However, it is difficult to quantitate the amount of PM deposited in rodent lungs following inhalation exposure, thus making fundamental dose-to-effect assessment and linkages to human responses problematic. To address this need, spontaneously hypertensive rats were exposed to an oil combustion-derived PM (HP12) via inhalation while being maintained in whole-body plethysmograph chambers. Rats were exposed 6 h/day to 13 mg/m(3) of HP12 for 1 or 4 days. Immediately following the last exposure, rats were sacrificed and their tracheas and lung lobes harvested and separated for neutron activation analysis. Total lower respiratory tract deposition ranged from 20-60 microg to 89-139 microg for 1- and 4-day exposures, respectively. Deposition data were compared to default and rat-specific estimates provided by the Multiple Path Particle Deposition (MPPD) model, yielding model predictions that were < 33% of the measured dose. This study suggests that HP12 exposure decreased particle clearance, as the mass of HP12 in the lungs following a 4-day protocol was nearly four times that observed after a 1-day exposure. This work should improve the ability of risk assessors to extrapolate rat-to-human exposure concentrations on the basis of lung burdens and, thus, better relate inhaled doses and resultant toxicological effects.

  20. Electrocatalytic performance of Pt nanoparticles sputter-deposited on indium tin oxide toward methanol oxidation reaction: The particle size effect

    NASA Astrophysics Data System (ADS)

    Ting, Chao-Cheng; Chao, Chih-Hsuan; Tsai, Cheng Yu; Cheng, I.-Kai; Pan, Fu-Ming

    2017-09-01

    We sputter-deposited Pt nanoparticles with an average size ranging from 2.0 nm to 8.5 nm on the indium-tin oxide (ITO) glass substrate, and studied the effect of the size of Pt nanoparticles on electrocatalytic activity of the Pt/ITO electrode toward methanol oxidation reaction (MOR) in acidic solution. X-ray photoelectron spectroscopy (XPS) reveals an interfacial oxidized Pt layer present between Pt nanoparticles and the ITO substrate, which may modify the surface electronic structure of Pt nanoparticles and thus influences the electrocatalytic properties of the Pt catalyst toward MOR. According to electrochemical analyses, smaller Pt nanoparticles exhibit slower kinetics for CO electrooxidation and MOR. However, a smaller particle size enables better CO tolerance because the bifunctional mechanism is more effective on smaller Pt nanoparticles. The electrocatalytic activity decays rapidly for Pt nanoparticles with a size smaller than 3 nm and larger than 8 nm. The rapid activity decay is attributed to Pt dissolution for smaller nanoparticles and to CO poisoning for larger ones. Pt nanoparticles of 5-6 nm in size loaded on ITO demonstrate a greatly improved electrocatalytic activity and stability compared with those deposited on different substrates in our previous studies.

  1. Further study on the effects of coffee cherry on spontaneous mammary tumourigenesis in mice: effects of methanol extract.

    PubMed

    Nagasawa, H; Yasuda, M; Inatomi, H

    1996-01-01

    To examine the effective components in the antitumourigenic role of water extract of coffee cherry (CC), and the residue after removal of beans, the dry matter of coffee cherry was extracted repeatedly by 60% methanol and further divided into water-soluble and -insoluble fractions (CC-W and CC-M, respectively). Free access to CC-W (0.25% in tap water) markedly inhibited mammary tumour development in SHN virgin mice, while it had no effect on the growth of normal and preneoplastic mammary glands and established tumours. Associated with this, urinary excretion of some components and intrathymic T cell differentiation were stimulated by the treatment with the CC. CC-W had little affect on the endocrine system, including serum prolactin level, oestrous cycles and endocrine organs, but retarded ovarian degeneration in mice developing mammary tumours. The finding in CC-W were generally similar to those in CC. Fat emulsion of CC-M, which was only checked for mammary tumour growth owing to the limited amount available, showed no effect at the dose level used (0.25% in drinking water). Finally, the previous and the present findings taken together strongly suggest that the effective components of coffee cherry are in the water-soluble fraction.

  2. Effects of HCl and Methanol in the Precursor on Physical Properties of Spray-Deposited Nanostructured CuO Thin Films for Solar Applications

    NASA Astrophysics Data System (ADS)

    Asl, Hassan Zare; Rozati, Seyed Mohammad

    2017-08-01

    The influence of the presence of HCl and methanol in the precursor on CuO absorber layers deposited by spray pyrolysis has been investigated. The films were deposited on glass substrate at fixed substrate temperature of 450°C using 0.05 molar CuCl2·2H2O in deionized water containing a specific amount of HCl and methanol. The structural, morphological, electrical, and optical properties of the resulting thin films were studied to evaluate their suitability for solar applications. Presence of HCl increased the concentration of Cu2+ ions in the precursor, leading to a rise in the Cu concentration in the resulting film, which improved the crystallinity with increased mean grain size, surface roughness, and carrier mobility at the cost of decreased carrier concentration. However, film deposited with excess HCl suffered from corrosion and huge cracks, making it unfavorable for solar applications. On the other hand, although presence of methanol improved the crystallinity of the resulting film, the surface was smooth due to lower deposition rate. Kubelka-Munk theory was used to estimate the optical bandgap of the deposited thin films, revealing values fairly close to optimum for solar cell applications.

  3. The kinetics and mechanism of methanol synthesis by hydrogenation of CO 2 over a Zn-deposited Cu(111) surface

    NASA Astrophysics Data System (ADS)

    Fujitani, T.; Nakamura, I.; Uchijima, T.; Nakamura, J.

    1997-07-01

    The hydrogenation of CO 2 over a Zn-deposited Cu(111) surface has been studied using an X-ray photoelectron spectroscopy (XPS) apparatus combined with a high-pressure flow reactor. It was shown that the turnover frequency (TOF) for methanol formation linearly increased with Zn coverage below ϑZn=0.19 and decreased above ϑZn=0.20. The optimum TOF obtained at ϑZn=0.19 was thirteen-fold larger than that of the Zn-free Cu(111) surface. On the other hand, the TOF for CO formation started to decrease at ϑZn=0.10 and approached zero at ϑZn=0.5. No promotional effect of Zn was thus observed for the reverse water-gas shift (RWGS) reaction on Cu(111). Post-reaction surface analysis by XPS showed the formation of formate species (HCOO a) on the Cu(111) surfaces. The formate coverage linearly increased with the Zn coverage below ϑZn=0.15, suggesting that the formation of the formate species was stabilized by the Zn species. The relation between ϑHCOO and ϑZn is similar to that between TOF and ϑZn; thus, the formate species is considered to be the reaction intermediates during methanol formation, and the amount of the formate species should determine the rate of the reaction. It was found that the surface chemistry of the Zn-deposited Cu surface drastically changed at ϑZn=0.15. At higher Zn coverages ( ϑZn>0.15), Zn on Cu(111) was readily oxidized to ZnO during the CO 2 hydrogenation reaction. On the other hand, at low Zn coverages below ϑZn=0.15, Zn was partially oxidized in the absence of oxygen in ZnO or O a on the Cu surface under the reaction conditions. It was suggested that the Zn on Cu(111) was directly bound to the oxygen in the surface formate species as the role of the active sites.

  4. Os layers spontaneously deposited on the Pt(111) electrode : XPS, STM and GIF-XAS study.

    SciTech Connect

    Rhee, C. K.; Wakisaka, M.; Tolmachev, Y.; Johnston, C.; Haasch, R.; Attenkofer, K.; Lu, G. Q.; You, H.; Wieckowski, A.; Univ. of Illinois Champaigh-Urbana

    2003-01-01

    Scanning tunneling microscopy (STM) characterized adlayers of spontaneously deposited osmium on a Pt(111) electrode were investigated using ex-situ X-ray photoemission spectroscopy (XPS) and in-situ grazing incidence fluorescence X-ray absorption spectroscopy (GIF-XAS). After a single spontaneous deposition, monoatomic (or nearly monoatomic) nanoislands of osmium are formed. The island diameter varies from 2 to 5 nm depending on the Os coverage, which in turn is adjusted by varying the concentration of the Os precursor salt (OsCl3) in the deposition bath and/or by the deposition time. XPS reveals three oxidation states: a metallic Os (the 4f7/2 core level binding energy of 50.8 eV), Os(IV) (51.5 eV) and Os(VIII) (52.4 eV). The metallic osmium exists at potentials below 500 mV (vs. RHE) while above 500 mV osmium is oxidized to Os(IV). Electrodissolution of osmium begins above 900 mV and occurs simultaneously with platinum oxidation. At ca. 1200 mV V versus the RHE reference, the oxidation state of some small amounts of osmium that survive dissolution is the Os(VIII). We demonstrate, for the first time, that mixed or odd valencies of osmium exist on the platinum surface at potentials higher that 800 mV. In-situ GIF-XAS measurements of an Os LIII edge also reveal the presence of three Os oxidation states. Namely, below the electrode potential of 400 mV, the X-ray fluorescent energy at maximum absorption is 10.8765 keV, and is characteristic of the metallic Os. In the potential range between 500 and 1000 mV this energy is gradually shifted to higher values, assignable to higher valencies of osmium, like Os(IV). This tendency continues to higher potentials consistent with the third, highly oxidized osmium form present, most likely Os(VIII). The variation of the 'raw edge jump height' of Os with the electrode potential, which is equivalent to a drop in osmium surface concentration, demonstrates that the electrochemical stripping of Os begins below 1.0 V versus RHE, as

  5. Ethanol oxidation on electrocatalysts obtained by spontaneous deposition of palladium onto nickel-zinc materials.

    PubMed

    Bambagioni, Valentina; Bianchini, Claudio; Filippi, Jonathan; Oberhauser, Werner; Marchionni, Andrea; Vizza, Francesco; Psaro, Rinaldo; Sordelli, Laura; Foresti, Maria Luisa; Innocenti, Massimo

    2009-01-01

    Ni-Zn and Ni-Zn-P alloys supported on Vulcan XC-72 are effective materials for the spontaneous deposition of palladium through redox transmetalation with Pd(IV) salts. The materials obtained, Pd-(Ni-Zn)/C and Pd-(Ni-Zn-P)/C, have been characterized by a variety of techniques. The analytical and spectroscopic data show that the surface of Pd-(Ni-Zn)/C and Pd-(Ni-Zn-P)/C contain very small, highly dispersed, and highly crystalline palladium clusters as well as single palladium sites, likely stabilized by interaction with oxygen atoms from Ni--O moieties. As a reference material, a nanostructured Pd/C material was prepared by reduction of an aqueous solution of PdCl(2)/HCl with ethylene glycol in the presence of Vulcan XC-72. In Pd/C, the Pd particles are larger, less dispersed, and much less crystalline. Glassy carbon electrodes coated with the Pd-(Ni-Zn)/C and Pd-(Ni-Zn-P)/C materials, containing very low Pd loadings (22-25 microg cm(-2)), were studied for the oxidation of ethanol in alkaline media in half cells and provided excellent results in terms of both specific current (as high as 3600 A g(Pd)(-1) at room temperature) and onset potential (as low as -0.6 V vs Ag/AgCl/KCl(sat)).

  6. Optimizing the deposition of hydrogen evolution sites on suspended semiconductor particles using on-line photocatalytic reforming of aqueous methanol solutions.

    PubMed

    Busser, G Wilma; Mei, Bastian; Muhler, Martin

    2012-11-01

    The deposition of hydrogen evolution sites on photocatalysts is a crucial step in the multistep process of synthesizing a catalyst that is active for overall photocatalytic water splitting. An alternative approach to conventional photodeposition was developed, applying the photocatalytic reforming of aqueous methanol solutions to deposit metal particles on semiconductor materials such as Ga₂O₃ and (Ga₀.₆ Zn₀.₄)(N₀.₆O₀.₄). The method allows optimizing the loading of the co-catalysts based on the stepwise addition of their precursors and the continuous online monitoring of the evolved hydrogen. Moreover, a synergetic effect between different co-catalysts can be directly established.

  7. Metal accumulation strategies in plants spontaneously inhabiting Zn-Pb waste deposits.

    PubMed

    Wójcik, Małgorzata; Sugier, Piotr; Siebielec, Grzegorz

    2014-07-15

    Metal (Zn, Pb, Cd, Cu, Ni, Cr) accumulation in shoots of 38 plant species spontaneously colonizing three Zn-Pb waste deposits in southern Poland was studied in order to find out if the age of the waste (30-130 years) or its type (slag or flotation residues) influence metal content in plants and to identify species potentially suitable for biomonitoring and phytoremediation. The total metal concentrations in the waste upper layers ranged from 7300 to 171,790 mg kg(-1) for Zn, from 1390 to 22,265 mg kg(-1) for Pb, and from 66 to 1,464 mg kg(-1) for Cd, whereas CaCl2-extracted fractions accounted for 0.034-0.11 %, 0.005-0.03 %, and 0.28-0.62 % of total Zn, Pb and Cd concentrations, respectively. The concentrations of Cu, Ni, and Cr in substrates and in plants were low and ranged within the background values. Metal accumulation in plant shoots was poorly correlated with both total and CaCl2-extracted forms of metals in the substrate and was highly variable among species and also specimens of the same species. The highest mean concentrations of Zn, Pb and Cd were found in Anthyllis vulneraria L. (901.5 mg kg(-1)), Echium vulgare L. (116.92 mg kg(-1)), and Hieracium piloselloides Vill. (26.86 mg kg(-1)), respectively. Besides Reseda lutea L., no species appeared to be a good indicator of polymetallic environment pollution based on chemical analysis of shoots; however, metal accumulation in the whole plant communities of a particular contaminated area might be an accurate tool for assessment of metal transfer to vegetation irrespective of the type or age of the waste. All the species studied developed a metal exclusion strategy, thus exhibiting potential for phytostabilization of metalliferous wastelands.

  8. Multi-laminated copper nanoparticles deposited on conductive substrates for electrocatalytic oxidation of methanol in alkaline electrolytes

    NASA Astrophysics Data System (ADS)

    Xia, Lun-Peng; Guo, Peng; Wang, Yan; Ding, Shi-Qi; He, Jian-Bo

    2014-09-01

    A simple electrodeposition approach to grow multi-laminated copper particles on two conductive substrates is presented. Morphological and structural characterization was performed using SEM and XRD. The copper crystallites are preferentially oriented with {111} planes parallel to the substrate surfaces, providing an optimum interface for methanol oxidation. There are a large number of edges, corners, and atomic steps around individual multi-laminated nanostructured particles. The excellent electrocatalytic activity of the particles to methanol oxidation in alkaline solutions is demonstrated by cyclic voltammetry, electrochemical impedance spectroscopy and chronoamperometry. The presence of the conductive poly(2-amino-5-mercapto-1,3,4-thiadiazole) interlayer between the Cu particles and the carbon paste substrate results in larger specific surface areas of the particles and smaller charge-transfer resistances of methanol oxidation reaction in the lower potential range. Such an anisotropic laminated structure of non-noble metal nanomaterials deserves further investigation for finding a suitable alternative to noble metal-based anodic catalysts in fuel cells.

  9. Spontaneous polarization of vapor-deposited 1-butanol films and its dependence on temperature

    NASA Astrophysics Data System (ADS)

    Gavra, Irini K.; Pilidi, Alexandra N.; Tsekouras, Athanassios A.

    2017-03-01

    Films of 1-butanol were vapor deposited under vacuum conditions at cryogenic temperatures on a polycrystalline platinum foil. Kelvin probe measurements showed the generation of a large negative voltage on the vacuum side of the film relative to its back side in contact with the platinum foil. Voltages across vapor deposited films, which are known to require molecules with an electric dipole moment, were confirmed to be proportional to the amount of gas deposited at a given temperature. Voltages of several hundreds of volts were recorded for films that were a few thousand monolayers thick. As deposition temperature was reduced from 120 K, the film voltage was found to increase almost linearly from 0 V until a little below 38 K, where the trend was reversed. Ramping up the sample temperature after deposition at 15 K/min exhibited an initial increase in absolute magnitude and then a gradual elimination of the voltage as the temperature of 120 K was reached. Both the initial increase and the subsequent decrease were found to be irreversible and indicate structural changes in the amorphous film. The elimination of the film voltage is associated with small rearrangements of the deposited molecules which are facilitated by the gradual increase of the temperature and the cumulative electric field of the surrounding molecules.

  10. Spontaneous polarization of vapor-deposited 1-butanol films and its dependence on temperature.

    PubMed

    Gavra, Irini K; Pilidi, Alexandra N; Tsekouras, Athanassios A

    2017-03-14

    Films of 1-butanol were vapor deposited under vacuum conditions at cryogenic temperatures on a polycrystalline platinum foil. Kelvin probe measurements showed the generation of a large negative voltage on the vacuum side of the film relative to its back side in contact with the platinum foil. Voltages across vapor deposited films, which are known to require molecules with an electric dipole moment, were confirmed to be proportional to the amount of gas deposited at a given temperature. Voltages of several hundreds of volts were recorded for films that were a few thousand monolayers thick. As deposition temperature was reduced from 120 K, the film voltage was found to increase almost linearly from 0 V until a little below 38 K, where the trend was reversed. Ramping up the sample temperature after deposition at 15 K/min exhibited an initial increase in absolute magnitude and then a gradual elimination of the voltage as the temperature of 120 K was reached. Both the initial increase and the subsequent decrease were found to be irreversible and indicate structural changes in the amorphous film. The elimination of the film voltage is associated with small rearrangements of the deposited molecules which are facilitated by the gradual increase of the temperature and the cumulative electric field of the surrounding molecules.

  11. Enhanced formic acid oxidation on polycrystalline platinum modified by spontaneous deposition of gold. Fourier transform infrared spectroscopy studies

    NASA Astrophysics Data System (ADS)

    Cappellari, Paula S.; García, Gonzalo; Florez-Montaño, Jonathan; Barbero, Cesar A.; Pastor, Elena; Planes, Gabriel A.

    2015-11-01

    Formic acid and adsorbed carbon monoxide electrooxidation on polycrystalline Pt and Au-modified Pt surfaces were studied by cyclic voltammetry, lineal sweep voltammetry and in-situ Fourier transform infrared spectroscopy techniques. With this purpose, a polycrystalline Pt electrode was modified by spontaneous deposition of gold atoms, achieving a gold surface coverage (θ) in the range of 0 ≤ θ ≤ 0.47. Results indicate the existence of two main pathways during the formic acid oxidation reaction, i.e. dehydration and dehydrogenation routes. At higher potentials than 0.5 V the dehydrogenation pathway appears to be the operative at both Pt and Au electrodes. Meanwhile, the dehydration reaction is the main pathway for Pt at lower potentials than 0.5 V. It was found that reaction routes are easily tuned by Au deposition on the Pt sites responsible for the formic acid dehydration reaction, and hence for the catalytic formation of adsorbed carbon monoxide. Gold deposition on these Pt open sites produces an enhanced activity toward the HCOOH oxidation reaction. In general terms, the surface inhibition of the reaction by adsorbed intermediates (indirect pathway) is almost absent at gold-modified Pt electrodes, and therefore the direct pathway appears as the main route during the formic acid electrooxidation reaction.

  12. Spontaneous Deposition of Prussian Blue on Multi-Walled Carbon Nanotubes and the Application in an Amperometric Biosensor

    PubMed Central

    Yao, Yanli; Bai, Xiaoyun; Shiu, Kwok-Keung

    2012-01-01

    A simple method has been developed for the spontaneous deposition of Prussian blue (PB) particles from a solution containing only ferricyanide ions onto conducting substrates such as indium tin oxide glass, glassy carbon disk and carbon nanotube (CNT) materials. Formation of PB deposits was confirmed by ultraviolet-visible absorption spectrometry and electrochemical techniques. The surface morphology of the PB particles deposited on the substrates was examined by atomic force microscopy and scanning electron microscopy. CNT/PB composite modified glassy carbon electrodes exhibited an electrocatalytic property for hydrogen peroxide reduction. These modified electrodes exhibited a high sensitivity for electrocatalytic reduction of hydrogen peroxide at −0.05 V (vs. Ag|AgCl), probably due to the synergistic effect of CNT with PB. Then, CNT/PB modified electrodes were further developed as amperometric glucose biosensors. These biosensors offered a linear response to glucose concentration from 0.1 to 0.9 mM with good selectivity, high sensitivity of 0.102 A M−1 cm−2 and short response time (within 2 s) at a negative operation potential of −0.05 V (vs. Ag|AgCl). The detection limit was estimated to be 0.01 mM at a signal-to-noise ratio of 3. PMID:28348317

  13. Spontaneous Electroless Galvanic Cell Deposition of 3D Hierarchical and Interlaced S-M-S Heterostructures.

    PubMed

    Tan, Chuan Fu; Azmansah, Siti Aishah Bte; Zhu, Hai; Xu, Qing-Hua; Ho, Ghim Wei

    2017-01-01

    One-pot electroless galvanic cell deposition of a 3D hierarchical semiconductor-metal-semiconductor interlaced nanoarray is demonstrated. The fabricated 3D photoanode deviates from the typical planar geometry, and aims to optimize the effective surface area for light harvesting and long-range charge transfer-collection pathways. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Photocatalytic hydrogen production by water/methanol decomposition using Au/TiO2 prepared by deposition-precipitation with urea.

    PubMed

    Oros-Ruiz, Socorro; Zanella, Rodolfo; López, Rosendo; Hernández-Gordillo, Agileo; Gómez, Ricardo

    2013-12-15

    Gold nanoparticles deposited on TiO2 Degussa P25, prepared by deposition-precipitation with urea, were studied in the photocatalytic hydrogen production. The effect of parameters such as mass of catalyst, gold loading, thermal treatment, and atmosphere of treatment was evaluated and optimized. The presence of metallic gold on the titania surface showed to have contributed to the high improvement in the activity of bare TiO2 for hydrogen generation under UV light (λ=254 nm) using a lamp of low energy (2W) consumption. The optimal gold loading for the photocatalysts was 0.5 wt.%, the mass of catalyst in the reactor was 0.5 g/L in a water/methanol 1:1 vol. solution, and the thermal treatment that produced the most active gold nanoparticles was found at 300°C. The photocatalysts thermally treated under hydrogen at 300°C produced 1492 μmol g(-1)h(-1) of hydrogen; the same catalyst activated in air produced 1866 μmo lg(-1)h(-1) of hydrogen.

  15. In situ surface-enhanced Raman spectroscopic study of formic acid electrooxidation on spontaneously deposited platinum on gold.

    PubMed

    Muralidharan, Ranjani; McIntosh, Michael; Li, Xiao

    2013-06-28

    Present formic acid fuel cell efficiency is limited by low kinetics at the anode, indicating the need for effective catalysts to improve the formic acid oxidation. As a prerequisite, the nature of adsorbed species and specifically the reaction intermediates formed in this process needs to be examined. This work focuses on the electrooxidation of formic acid and the nature of the intermediates at a platinum-modified gold surface prepared through spontaneous deposition using a combination of electrochemistry and in situ surface enhanced Raman spectroscopy (SERS). This Pt-modified gold electrode surface assists in oxidizing formic acid at potentials as low as 0.0 V vs. Ag/AgCl which is 0.15 V more negative than a bare Pt surface. The oxidation current obtained on the Pt-modified gold electrode is 72 times higher than on a bare Au surface and 5 times higher than on a bare Pt surface at the same potential. In situ SERS has revealed the involvement of formate at a low frequency as the primary intermediate in this electrooxidation process. While previous studies mainly focused on the formate mode at ca. 1322 cm(-1), it is the first time that a formate peak at ca. 300 cm(-1) was observed on a Pt or Pt-associated surface. A unique relationship has been observed between the formic acid oxidation currents and the SERS intensity of this formate adsorbate. Furthermore, the characteristic Stark effect of the formate proves the strong interaction between the adsorbate and the catalyst. Both electrochemical and spectroscopic results suggest that the formic acid electrooxidation takes place by the dehydrogenation pathway involving a low frequency formate intermediate on the Pt-modified gold electrode catalyst.

  16. Method for making methanol

    DOEpatents

    Mednick, R. Lawrence; Blum, David B.

    1986-01-01

    Methanol is made in a liquid-phase methanol reactor by entraining a methanol-forming catalyst in an inert liquid and contacting said entrained catalyst with a synthesis gas comprising hydrogen and carbon monoxide.

  17. Method for making methanol

    DOEpatents

    Mednick, R. Lawrence; Blum, David B.

    1987-01-01

    Methanol is made in a liquid-phase methanol reactor by entraining a methanol-forming catalyst in an inert liquid and contacting said entrained catalyst with a synthesis gas comprising hydrogen and carbon monoxide.

  18. In situ electro-deposition of Pt micro-nano clusters on the surface of {[PMo12O40]3-/PAMAM}n multilayer composite films and their electrocatalytic activities regarding methanol oxidation.

    PubMed

    Li, Zhong-Shui; Lin, Shen; Chen, Zu-liang; Shi, Yuan-De; Huang, Xiao-Mei

    2012-02-15

    The {[PMo(12)O(40)](3-)/PAMAM}(n) multilayer films are prepared by LBL electrostatic assembly technique, and their uniform and homogeneous traits have been verified by cyclic voltammetry. The {[PMo(12)O(40)](3-)/PAMAM}(n) multilayer films with PAMAM as the outmost layer, having an open structure and exhibiting good penetrability for the solvent molecules at low pH, are used as matrices for electro-deposition of Pt micro-nano clusters in situ. X-ray photoelectron spectroscopy (XPS) analysis and field emission scanning electron microscope (FE-SEM) characterization show that the unique Pt micro-nano clusters with flower-like structure have been immobilized on the surface of {[PMo(12)O(40)](3-)/PAMAM}(n) multilayer films. The morphologies of Pt micro-nano clusters are influenced by electro-deposition conditions such as deposition potential, deposition time, and the number of layers of {[PMo(12)O(40)](3-)/PAMAM}(n) multilayer films. Pt(-clusters)-{PMo(12)/PAMAM}(3) composite films demonstrate good electrocatalytic activities regarding methanol oxidation and improved tolerance of CO.

  19. Correlating the chemical composition and size of various metal oxide substrates with the catalytic activity and stability of as-deposited Pt nanoparticles for the methanol oxidation reaction

    SciTech Connect

    Megan E. Scofield; Wong, Stanislaus S.; Koenigsmann, Christopher; Bobb-Semple, Dara; Tao, Jing; Tong, Xiao; Wang, Lei; Lewis, Crystal S.; Vuklmirovic, Miomir; Zhu, Yimei; Adzic, Radoslav R.

    2015-12-09

    The performance of electrode materials in conventional direct alcohol fuel cells (DAFC) is constrained by (i) the low activity of the catalyst materials relative to their overall cost, (ii) the poisoning of the active sites due to the presence of partially oxidized carbon species (such as but not limited to CO, formate, and acetate) produced during small molecule oxidation, and (iii) the lack of catalytic stability and durability on the underlying commercial carbon support. Therefore, as a viable alternative, we have synthesized various metal oxide and perovskite materials of different sizes and chemical compositions as supports for Pt nanoparticles (NPs). Our results including unique mechanistic studies demonstrate that the SrRuO3 substrate with immobilized Pt NPs at its surface evinces the best methanol oxidation performance as compared with all of the other substrate materials tested herein, including commercial carbon itself. In addition, data from electron energy loss spectroscopy (EELS) and X-ray photoelectron spectroscopy (XPS) confirmed the presence of electron transfer from bound Pt NPs to surface Ru species within the SrRuO3 substrate itself, thereby suggesting that favorable metal support interactions are responsible for the increased methanol oxidation reaction (MOR) activity of Pt species with respect to the underlying SrRuO3 composite catalyst material.

  20. Correlating the chemical composition and size of various metal oxide substrates with the catalytic activity and stability of as-deposited Pt nanoparticles for the methanol oxidation reaction

    DOE PAGES

    Megan E. Scofield; Wong, Stanislaus S.; Koenigsmann, Christopher; ...

    2015-12-09

    The performance of electrode materials in conventional direct alcohol fuel cells (DAFC) is constrained by (i) the low activity of the catalyst materials relative to their overall cost, (ii) the poisoning of the active sites due to the presence of partially oxidized carbon species (such as but not limited to CO, formate, and acetate) produced during small molecule oxidation, and (iii) the lack of catalytic stability and durability on the underlying commercial carbon support. Therefore, as a viable alternative, we have synthesized various metal oxide and perovskite materials of different sizes and chemical compositions as supports for Pt nanoparticles (NPs).more » Our results including unique mechanistic studies demonstrate that the SrRuO3 substrate with immobilized Pt NPs at its surface evinces the best methanol oxidation performance as compared with all of the other substrate materials tested herein, including commercial carbon itself. In addition, data from electron energy loss spectroscopy (EELS) and X-ray photoelectron spectroscopy (XPS) confirmed the presence of electron transfer from bound Pt NPs to surface Ru species within the SrRuO3 substrate itself, thereby suggesting that favorable metal support interactions are responsible for the increased methanol oxidation reaction (MOR) activity of Pt species with respect to the underlying SrRuO3 composite catalyst material.« less

  1. Spontaneous glomerular sclerosis in aging Sprague-Dawley rats. I. Lesions associated with mesangial IgM deposits.

    PubMed Central

    Bolton, W. K.; Benton, F. R.; Maclay, J. G.; Sturgill, B. C.

    1976-01-01

    The present studies examined the pathogenesis of focal glomerular sclerosis in aging rats. A marked difference in development of the lesion was noted between males and females, and strain variability was an important factor. Increased glomerular basement membrane permeability with loss of selectivity unrelated to changes in glomerular sialoprotein occurred with aging and was accompanied by increasing proteinuria. Noncomplement-fixing mesangial deposits of rat IgM were present after 1 month of age and were also found in lesser amounts in germfree rats. Fluoresceinated eluates of rat kidneys did not have antibody activity against rat serum or tissue antigens. There was no evidence for a pathogenetic role of IgM deposits. Rat IgG, IgA, IgE, C3, and fibrin were occasionally found in sclerotic areas. Analysis of multiple histologic sections revealed a close correlation between aging and glomerular pathology, with a poor correlation between tubular damage and aging. Glomerular damage appeared to be the initial event leading to tubular damage. Indirect evidence suggests that a relative thymic deficiency may play an important role in the pathogenesis of the lesion. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:793408

  2. Enhanced Photoluminescence and Raman Properties of Al-Doped ZnO Nanostructures Prepared Using Thermal Chemical Vapor Deposition of Methanol Assisted with Heated Brass

    PubMed Central

    Thandavan, Tamil Many K.; Gani, Siti Meriam Abdul; San Wong, Chiow; Md. Nor, Roslan

    2015-01-01

    Vapor phase transport (VPT) assisted by mixture of methanol and acetone via thermal evaporation of brass (CuZn) was used to prepare un-doped and Al-doped zinc oxide (ZnO) nanostructures (NSs). The structure and morphology were characterized by field emission scanning electron microscopy (FESEM) and x-ray diffraction (XRD). Photoluminescence (PL) properties of un-doped and Al-doped ZnO showed significant changes in the optical properties providing evidence for several types of defects such as zinc interstitials (Zni), oxygen interstitials (Oi), zinc vacancy (Vzn), singly charged zinc vacancy (VZn-), oxygen vacancy (Vo), singly charged oxygen vacancy (Vo+) and oxygen anti-site defects (OZn) in the grown NSs. The Al-doped ZnO NSs have exhibited shifted PL peaks at near band edge (NBE) and red luminescence compared to the un-doped ZnO. The Raman scattering results provided evidence of Al doping into the ZnO NSs due to peak shift from 145 cm-1 to an anomalous peak at 138 cm-1. Presence of enhanced Raman signal at around 274 and 743 cm-1 further confirmed Al in ZnO NSs. The enhanced D and G band in all Al-doped ZnO NSs shows possible functionalization and doping process in ZnO NSs. PMID:25756598

  3. Enhanced photoluminescence and Raman properties of Al-Doped ZnO nanostructures prepared using thermal chemical vapor deposition of methanol assisted with heated brass.

    PubMed

    Thandavan, Tamil Many K; Gani, Siti Meriam Abdul; San Wong, Chiow; Md Nor, Roslan

    2015-01-01

    Vapor phase transport (VPT) assisted by mixture of methanol and acetone via thermal evaporation of brass (CuZn) was used to prepare un-doped and Al-doped zinc oxide (ZnO) nanostructures (NSs). The structure and morphology were characterized by field emission scanning electron microscopy (FESEM) and x-ray diffraction (XRD). Photoluminescence (PL) properties of un-doped and Al-doped ZnO showed significant changes in the optical properties providing evidence for several types of defects such as zinc interstitials (Zni), oxygen interstitials (Oi), zinc vacancy (Vzn), singly charged zinc vacancy (VZn-), oxygen vacancy (Vo), singly charged oxygen vacancy (Vo+) and oxygen anti-site defects (OZn) in the grown NSs. The Al-doped ZnO NSs have exhibited shifted PL peaks at near band edge (NBE) and red luminescence compared to the un-doped ZnO. The Raman scattering results provided evidence of Al doping into the ZnO NSs due to peak shift from 145 cm-1 to an anomalous peak at 138 cm-1. Presence of enhanced Raman signal at around 274 and 743 cm-1 further confirmed Al in ZnO NSs. The enhanced D and G band in all Al-doped ZnO NSs shows possible functionalization and doping process in ZnO NSs.

  4. Evaluation of uncertainty and detection limits in 210Pb and 210Po measurement in water by alpha spectrometry using 210Po spontaneous deposition onto a silver disk.

    PubMed

    Fernández, Pedro L; Gómez, José; Ródenas, Carmen

    2012-04-01

    An easy and accurate method for the determination of (210)Pb and (210)Po in water using (210)Po spontaneous deposition onto a silver disk is proposed and assessed for its detection capabilities according to the ISO Guide for the expression of uncertainty in measurement (GUM) and ISO Standard 11929-7 concerning the evaluation of the characteristic limits for ionizing radiation measurements. The method makes no assumption on the initial values of the activity concentrations of (210)Pb, (210)Bi and (210)Po in the sample to be analyzed, and is based on the alpha spectrometric measurement of (210)Po in two different aliquots: the first one measured five weeks after the sampling date to ensure radioactive equilibrium between (210)Pb and (210)Bi and the second after a sufficient time for the ingrowth of (210)Po from (210)Pb to be significant. As shown, for a recommended time interval of seven months between (210)Po measurements, the applicability of the proposed method is limited to water samples with a (226)Ra to (210)Pb activity ratio C(Ra)/C(Pb) ≤ 4, as usual in natural waters. Using sample and background counting times of 24h and 240 h, respectively, the detection limit of the activity concentration of each radionuclide at the sampling time for a 1L sample typically varies between 0.7 and 16 mBq L(-1) for (210)Pb in water samples with an initial activity of (210)Po in the range 0-200 mBq L(-1), and between 0.6 and 8.5 mBq L(-1) for (210)Po in water samples with an initial activity of (210)Pb in the same range.

  5. Formation and spectra of clathrate hydrates of methanol and methanol-ether mixtures

    NASA Astrophysics Data System (ADS)

    Williams, Kenneth Dixon; Devlin, J. Paul

    1997-10-01

    Infrared spectra of mixed clathrate hydrates, with either ethylene oxide (EO) or tetrahydrofuran (THF) and methanol molecules as the guest species, have been obtained from thin films prepared by vapor deposition of D 2O mixtures in the 115-130 K range. Although methanol acts as a suppressant to the direct vapor deposition of a type I clathrate with EO, nearly complete conversion of 115 K amorphous codeposits, to the crystalline mixed clathrate, occurs upon warming near 150 K. By contrast, the type II clathrate of THF shows an increased crystalline quality when methanol is included in the vapor deposits of the mixed clathrate hydrate at 130 K. The observation of the OD stretch-mode band of weakly bonded CD 3OD near 2575 cm -1 is part of the evidence that the methanol molecules are encaged. However, as shown theoretically by Tanaka, the clathrate hydrates of methanol, even when mixed with an ether help gas, are not stable structures but form at low temperatures because of kinetic factors, only to decompose in the 140-160 K range. Attempts to prepare a simple type I or type II clathrate hydrate of methanol have produced mixed results. Limited amounts of clathrate hydrate form during deposition but annealing does not result in complete conversion to crystalline clathrates, particularly for host : guest ratios of 17 : 1.

  6. The Methanol Economy Project

    SciTech Connect

    Olah, George; Prakash, G. K.

    2014-02-01

    The Methanol Economy Project is based on the concept of replacing fossil fuels with methanol generated either from renewable resources or abundant natural (shale) gas. The full methanol cycle was investigated in this project, from production of methanol through bromination of methane, bireforming of methane to syngas, CO2 capture using supported amines, co-electrolysis of CO2 and water to formate and syngas, decomposition of formate to CO2 and H2, and use of formic acid in a direct formic acid fuel cell. Each of these projects achieved milestones and provided new insights into their respective fields.

  7. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, Shabbir; Kumar, Romesh; Krumpelt, Michael

    1999-01-01

    A partial oxidation reformer comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell.

  8. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, S.; Kumar, R.; Krumpelt, M.

    1999-08-17

    A partial oxidation reformer is described comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell. 7 figs.

  9. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, S.; Kumar, R.; Krumpelt, M.

    1999-08-24

    A partial oxidation reformer is described comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell. 7 figs.

  10. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, Shabbir; Kumar, Romesh; Krumpelt, Michael

    2001-01-01

    A partial oxidation reformer comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell.

  11. Methanol partial oxidation reformer

    DOEpatents

    Ahmed, Shabbir; Kumar, Romesh; Krumpelt, Michael

    1999-01-01

    A partial oxidation reformer comprising a longitudinally extending chamber having a methanol, water and an air inlet and an outlet. An igniter mechanism is near the inlets for igniting a mixture of methanol and air, while a partial oxidation catalyst in the chamber is spaced from the inlets and converts methanol and oxygen to carbon dioxide and hydrogen. Controlling the oxygen to methanol mole ratio provides continuous slightly exothermic partial oxidation reactions of methanol and air producing hydrogen gas. The liquid is preferably injected in droplets having diameters less than 100 micrometers. The reformer is useful in a propulsion system for a vehicle which supplies a hydrogen-containing gas to the negative electrode of a fuel cell.

  12. Dietary methanol and autism.

    PubMed

    Walton, Ralph G; Monte, Woodrow C

    2015-10-01

    The authors sought to establish whether maternal dietary methanol during pregnancy was a factor in the etiology of autism spectrum disorders. A seven item questionnaire was given to women who had given birth to at least one child after 1984. The subjects were solicited from a large primary care practice and several internet sites and separated into two groups - mothers who had given birth to a child with autism and those who had not. Average weekly methanol consumption was calculated based on questionnaire responses. 550 questionnaires were completed by women who gave birth to a non-autistic child. On average these women consumed 66.71mg. of methanol weekly. 161 questionnaires were completed by women who had given birth to an autistic child. The average estimated weekly methanol consumption for this group was 142.31mg. Based on the results of the Wilcoxon rank sum-test, we see a significant difference between the reported methanol consumption rates of the two groups. This study suggests that women who have given birth to an autistic child are likely to have had higher intake of dietary sources of methanol than women who have not. Further investigation of a possible link of dietary methanol to autism is clearly warranted.

  13. Deactivation of ceria-based SOFC anodes in methanol

    NASA Astrophysics Data System (ADS)

    Kim, Taeyoon; Ahn, Kipyung; Vohs, John M.; Gorte, Raymond J.

    The performance and stability of Cu-ceria-YSZ (yttria-stabilized zirconia) and carbon-ceria-YSZ, solid-oxide-fuel-cell (SOFC) anodes were examined in neat (100%) methanol at 973 K and compared to the performance of the same anodes in dry H 2. The presence of Cu catalyzed the decomposition of methanol, so that the initial performance of cells with Cu-ceria-YSZ anodes was similar to CO and H 2. However, with carbon-ceria-YSZ anodes, the open-circuit voltage was significantly higher and the reaction over-potential significantly lower in methanol than in H 2, suggesting that methanol is a more effective reductant of the anode three-phase boundary region. Carbon-ceria-YSZ anodes were found to undergo rapid and irreversible deactivation in methanol. Steady-state rates of methanol decomposition over ceria-YSZ were found to undergo a similar deactivation as the carbon-ceria anodes. Although no evidence for carbon deposition was observed with methanol at 973 K, the addition of steam was found to partially stabilize both anode and catalyst performance. Scanning electron microscopy (SEM) of ceria particles in YSZ showed a large change in the morphology of the ceria particles when the samples were heated in methanol, while negligible changes were observed when heating in H 2. It is suggested that the results with methanol can be explained as resulting from the very low P(O 2) that is effectively produced by having methanol in contact with ceria.

  14. The Methanol Multibeam Survey

    NASA Astrophysics Data System (ADS)

    Green, James A.; Cohen, R. J.; Caswell, J. L.; Fuller, G. A.; Brooks, K.; Burton, M. G.; Chrysostomou, A.; Diamond, P. J.; Ellingsen, S. P.; Gray, M. D.; Hoare, M. G.; Masheder, M. R. W.; McClure-Griffiths, N.; Pestalozzi, M.; Phillips, C.; Quinn, L.; Thompson, M. A.; Voronkov, M.; Walsh, A.; Ward-Thompson, D.; Wong-McSweeney, D.; Yates, J. A.; Cox, J.

    2007-03-01

    A new 7-beam methanol multibeam receiver is being used to survey the Galaxy for newly forming massive stars, that are pinpointed by strong methanol maser emission at 6.668 GHz. The receiver, jointly constructed by Jodrell Bank Observatory (JBO) and the Australia Telescope National Facility (ATNF), was successfully commissioned at Parkes in January 2006. The Parkes-Jodrell survey of the Milky Way for methanol masers is two orders of magnitude faster than previous systematic surveys using 30-m class dishes, and is the first systematic survey of the entire Galactic plane. The first 53 days of observations with the Parkes telescope have yielded 518 methanol sources, of which 218 are new discoveries. We present the survey methodology as well as preliminary results and analysis.

  15. Methanol Cannon Demonstrations Revisited.

    ERIC Educational Resources Information Center

    Dolson, David A.; And Others

    1995-01-01

    Describes two variations on the traditional methanol cannon demonstration. The first variation is a chain reaction using real metal chains. The second example involves using easily available components to produce sequential explosions that can be musical in nature. (AIM)

  16. Methanol Cannon Demonstrations Revisited.

    ERIC Educational Resources Information Center

    Dolson, David A.; And Others

    1995-01-01

    Describes two variations on the traditional methanol cannon demonstration. The first variation is a chain reaction using real metal chains. The second example involves using easily available components to produce sequential explosions that can be musical in nature. (AIM)

  17. Spontaneous Fission

    DOE R&D Accomplishments Database

    Segre, Emilio

    1950-11-22

    The first attempt to discover spontaneous fission in uranium was made by [Willard] Libby, who, however, failed to detect it on account of the smallness of effect. In 1940, [K. A.] Petrzhak and [G. N.] Flerov, using more sensitive methods, discovered spontaneous fission in uranium and gave some rough estimates of the spontaneous fission decay constant of this substance. Subsequently, extensive experimental work on the subject has been performed by several investigators and will be quoted in the various sections. [N.] Bohr and [A.] Wheeler have given a theory of the effect based on the usual ideas of penetration of potential barriers. On this project spontaneous fission has been studied for the past several years in an effort to obtain a complete picture of the phenomenon. For this purpose the spontaneous fission decay constants {lambda} have been measured for separated isotopes of the heavy elements wherever possible. Moreover, the number {nu} of neutrons emitted per fission has been measured wherever feasible, and other characteristics of the spontaneous fission process have been studied. This report summarizes the spontaneous fission work done at Los Alamos up to January 1, 1945. A chronological record of the work is contained in the Los Alamos monthly reports.

  18. The Asian methanol market

    SciTech Connect

    Nagase, Hideki

    1995-12-31

    For the purpose of this presentation, Asia has been broadly defined as a total of 15 countries, namely Japan, Korea, Taiwan, China, Hong Kong, the Philippines, Thailand, Malaysia, Singapore, Indonesia, Myanmar, India, Vietnam, Australia and New Zealand. In 1994 and the first half of 1995, the methanol industry and its derivative industries experienced hard time, because of extraordinarily high methanol prices. In spite of this circumstance, methanol demand in Asian countries has been growing steadily and remarkably, following Asian high economic growth. Most of this growth in demand has been and will continue to be met by outside supply. However, even with increased import of methanol from outside of Asia, as a result of this growth, Asian trade volume will be much larger in the coming years. Asian countries must turn their collective attention to making logistics and transportation for methanol and its derivatives more efficient in the Asian region to make better use of existing supply resources. The author reviews current economic growth as his main topic, and explains the forecast of the growth of methanol demand and supply in Asian countries in the near future.

  19. Spontaneous Pt Deposition on Defective Surfaces of In2O3 Nanocrystals Confined within Cavities of Hollow Silica Nanoshells: Pt Catalyst-Modified ITO Electrode with Enhanced ECL Performance.

    PubMed

    Cho, Young Shin; Kim, Soo Min; Ju, Youngwon; Kim, Junghoon; Jeon, Ki-Wan; Cho, Seung Hwan; Kim, Joohoon; Lee, In Su

    2017-06-21

    Although the deposition of metallic domains on a preformed semiconductor nanocrystal provides an effective pathway to access diverse hybrid nanocrystals with synergistic metal/semiconductor heterojunction interface, those reactions that take place on the surface of semiconductor nanoscrystals have not been investigated thoroughly, because of the impediments caused by the surface-capping organic surfactants. By exploiting the interfacial reactions occurring between the solution and nanoparticles confined with the cavities of hollow nanoparticles, we propose a novel nanospace-confined strategy for assessing the innate reactivity of surfaces of inorganic semiconductor nanoparticles. This strategy was adopted to investigate the newly discovered process of spontaneous Pt deposition on In2O3 nanocrystals. Through an in-depth examination involving varying key reaction parameters, the Pt deposition process was identified to be templated by the defective In2O3 surface via a unique redox process involving the oxygen vacancies in the In2O3 lattice, whose density can be controlled by high-temperature annealing. The product of the Pt-deposition reaction inside the hollow silica nanoparticle, bearing In2O3-supported Pt catalysts inside the cavity protected by a porous silica shell, was proved to be an effective nanoreactor system which selectively and sustainably catalyzed the reduction reaction of small-sized aromatic nitro-compounds. Moreover, the surfactant-free and electroless Pt deposition protocol, which was devised based on the surface chemistry of the In2O3 nanoparticles, was successfully employed to fabricate Pt-catalyst-modified ITO electrodes with enhanced electrogenerated chemiluminescece (ECL) performance.

  20. Methanol in dark clouds

    NASA Technical Reports Server (NTRS)

    Friberg, P.; Hjalmarson, A.; Madden, S. C.; Irvine, W. M.

    1988-01-01

    The first observation of methanol in cold dark clouds TMC 1, L 134 N, and B 335 is reported. In all three clouds, the relative abundance of methanol was found to be in the range of 10 to the -9th (i.e., almost an order of magnitude more abundant than acetaldehyde), with no observable variation between the clouds. Methanol emission showed a complex velocity structure; in TMC 1, clear indications of non-LTE were observed. Dimethyl ether was searched for in L 134 N; the upper limit of the column density of dimethyl ether in L 134 N was estimated to be 4 x 10 to the 12th/sq cm, assuming 5 K rotation temperature and LTE. This limit makes the abundance ratio (CH3)2O/CH3OH not higher than 1/5, indicating that dimethyl ether is not overabundant in this dark cloud.

  1. Methanol in dark clouds

    NASA Technical Reports Server (NTRS)

    Friberg, P.; Hjalmarson, A.; Madden, S. C.; Irvine, W. M.

    1988-01-01

    The first observation of methanol in cold dark clouds TMC 1, L 134 N, and B 335 is reported. In all three clouds, the relative abundance of methanol was found to be in the range of 10 to the -9th (i.e., almost an order of magnitude more abundant than acetaldehyde), with no observable variation between the clouds. Methanol emission showed a complex velocity structure; in TMC 1, clear indications of non-LTE were observed. Dimethyl ether was searched for in L 134 N; the upper limit of the column density of dimethyl ether in L 134 N was estimated to be 4 x 10 to the 12th/sq cm, assuming 5 K rotation temperature and LTE. This limit makes the abundance ratio (CH3)2O/CH3OH not higher than 1/5, indicating that dimethyl ether is not overabundant in this dark cloud.

  2. Methanol contamination in traditionally fermented alcoholic beverages: the microbial dimension.

    PubMed

    Ohimain, Elijah Ige

    2016-01-01

    Incidence of methanol contamination of traditionally fermented beverages is increasing globally resulting in the death of several persons. The source of methanol contamination has not been clearly established in most countries. While there were speculations that unscrupulous vendors might have deliberately spiked the beverages with methanol, it is more likely that the methanol might have been produced by contaminating microbes during traditional ethanol fermentation, which is often inoculated spontaneously by mixed microbes, with a potential to produce mixed alcohols. Methanol production in traditionally fermented beverages can be linked to the activities of pectinase producing yeast, fungi and bacteria. This study assessed some traditional fermented beverages and found that some beverages are prone to methanol contamination including cachaca, cholai, agave, arak, plum and grape wines. Possible microbial role in the production of methanol and other volatile congeners in these fermented beverages were discussed. The study concluded by suggesting that contaminated alcoholic beverages be converted for fuel use rather than out rightly banning the age-long traditional alcohol fermentation.

  3. A case of methanol intoxication caused by methomyl pesticide ingestion.

    PubMed

    Gil, H W; Hong, J R; Song, H Y; Hong, S Y

    2012-12-01

    When clinicians treat patients with pesticide poisoning, they often pay attention only to the chief toxic agent and ignore the toxicity of the pesticide's additives or solvents. Occasionally, however, a solvent (e.g. methanol) may itself be the cause of poisoning. We report a case of acute methanol intoxication that occurred after ingestion of a methomyl pesticide that contained methanol as an additive. A 49-year-old man was brought to the emergency department in an unconscious state after ingestion of 20 ml of a carbamate pesticide (chief ingredient: methomyl; active ingredient: methanol). Upon arrival, he was semicomatose and did not breathe spontaneously; however, his cholinesterase level was within normal limits and cholinergic symptoms were not observed. High anion gap metabolic acidosis was present. His blood ethanol level was 74.8 mg/dL. The urine methanol level was 55.60 mg/dL, and urine ethanol level was 22.0 mg/dL. He was treated with hemodialysis; subsequently, his metabolic acidosis resolved and he returned to normal mental status. We guessed that methanol, as the solvent of the methomyl, had produced the symptoms. When treating pesticide-poisoned patients, clinicians should identify the solvent used in the pesticide, because solvents such as methanol may exacerbate the symptoms of poisoned patients.

  4. Methanol fuel mixture

    SciTech Connect

    Thrasher, D.A.; Greiner, L.; Cooper, G.

    1990-06-12

    This patent describes a fuel composition. It comprises: a major portion of fuel comprising 85 to 95% by volume of methanol; demineralized water, from 3 to 15% of the fuel; a fluorosurfactant for increasing the lubricity of the fuel, comprising approximately 0.01 to 0.05 weight percent of the fuel.

  5. Methanol from coal

    NASA Technical Reports Server (NTRS)

    Miller, D. R.

    1978-01-01

    Economic feasibility of methanol or methyl fuel produced from coal using existing technology is discussed. Other factors considered include environmental, safety, toxicity, transportation, so storage, ease of burning, and retrofitting of present boilers. Demonstrations of its uses as a boiler fuel and as a turbine fuel are cited.

  6. Methanol and acetaldehyde fluxes over ryegrass

    NASA Astrophysics Data System (ADS)

    Custer, Thomas; Schade, Gunnar

    2007-09-01

    Oxygenated volatile organic compounds (OVOCs) play an active role in tropospheric chemistry but our knowledge concerning their release and ultimate fate is limited. However, the recent introduction of Proton Transfer Reaction Mass Spectrometry (PTRMS) has improved our capability to make direct field observations of OVOC mixing ratios and fluxes. We used PTRMS in an eddy covariance setup to measure selected OVOC exchange rates above a well-characterized agricultural plot in Northern Germany. In fall 2003, mixing ratios of methanol and acetaldehyde 2 m above the field ranged from 1 to 10 and 0.4 to 2.1 ppb, respectively, well correlated with one another. Fluxes of both gases were followed for growing Italian ryegrass (Lolium multiflorum) over a significant portion of its life cycle. Diurnally fluctuating emissions of methanol and very small acetaldehyde fluxes were observed up to the cutting and removal of the grass. Methanol emissions were exponentially related to ambient temperatures and appeared to be higher during the grass' rapid leaf area expansion and after a rain event. Acetaldehyde exchanges averaged over the whole period indicated very slow deposition. Our measurements confirm previous, similar results, as well as presumptions that grasses are comparatively low methanol emitters compared to non-grass species.

  7. The Development of Methanol Industry and Methanol Fuel in China

    SciTech Connect

    Li, W.Y.; Li, Z.; Xie, K.C.

    2009-07-01

    In 2007, China firmly established itself as the driver of the global methanol industry. The country became the world's largest methanol producer and consumer. The development of the methanol industry and methanol fuel in China is reviewed in this article. China is rich in coal but is short on oil and natural gas; unfortunately, transportation development will need more and more oil to provide the fuel. Methanol is becoming a dominant alternative fuel. China is showing the rest of the world how cleaner transportation fuels can be made from coal.

  8. Two new methanol converters

    SciTech Connect

    Westerterp, K.R.; Bodewes, T.N.; Vrijiand, M.S.A.; Kuczynski, M. )

    1988-11-01

    Two novel converter systems were developed for the manufacture of methanol from synthesis gas: the Gas-Solid-Solid Trickle Flow Reactor (GSSTFR) and the Reactor System with Interstage Product Removal (RSIPR). In the GSSTFR version, the product formed at the catalyst surface is directly removed from the reaction zone by means of a solid adsorbent. This adsorbent continuously trickles over the catalyst bed. High reactant conversions up to 100% can be achieved in a single pass so that the usual recycle loop for the unconverted reactants is absent or greatly reduced in size. In the RSIPR version, high conversions per pass are achieved in a series of adiabatic or isothermal fixed bed reactors with selective product removal in absorbers between the reactor stages. The feasibility and economics of the two systems are discussed on the basis of 1,000 tpd methanol plants compared with a low-pressure Lurgi system.

  9. Eucomic acid methanol monosolvate

    PubMed Central

    Li, Guo-Qiang; Li, Yao-Lan; Wang, Guo-Cai; Liang, Zhi-Hong; Jiang, Ren-Wang

    2011-01-01

    In the crystal structure of the title compound [systematic name: 2-hy­droxy-2-(4-hy­droxy­benz­yl)butane­dioic acid methanol monosolvate], C11H12O6·CH3OH, the dihedral angles between the planes of the carboxyl groups and the benzene ring are 51.23 (9) and 87.97 (9)°. Inter­molecular O—H⋯O hydrogen-bonding inter­actions involving the hy­droxy and carb­oxy­lic acid groups and the methanol solvent mol­ecule give a three-dimensional structure. PMID:22091200

  10. An ecosystem-scale perspective of the net land methanol flux. Synthesis of micrometeorological flux measurements

    SciTech Connect

    Wohlfahrt, G.; Amelynck, C.; Ammann, C.; Arneth, A.; Bamberger, I.; Goldstein, A. H.; Gu, L.; Guenther, A.; Hansel, A.; Heinesch, B.; Holst, T.; Hörtnagl, L.; Karl, T.; Laffineur, Q.; Neftel, A.; McKinney, K.; Munger, J. W.; Pallardy, S. G.; Schade, G. W.; Seco, R.; Schoon, N.

    2015-07-09

    Methanol is the second most abundant volatile organic compound in the troposphere and plays a significant role in atmospheric chemistry. While there is consensus about the dominant role of living plants as the major source and the reaction with OH as the major sink of methanol, global methanol budgets diverge considerably in terms of source/sink estimates, reflecting uncertainties in the approaches used to model and the empirical data used to separately constrain these terms. Here we compiled micrometeorological methanol flux data from eight different study sites and reviewed the corresponding literature in order to provide a first cross-site synthesis of the terrestrial ecosystem-scale methanol exchange and present an independent data-driven view of the land–atmosphere methanol exchange. Our study shows that the controls of plant growth on production, and thus the methanol emission magnitude, as well as stomatal conductance on the hourly methanol emission variability, established at the leaf level, hold across sites at the ecosystem level. Unequivocal evidence for bi-directional methanol exchange at the ecosystem scale is presented. Deposition, which at some sites even exceeds methanol emissions, represents an emerging feature of ecosystem-scale measurements and is likely related to environmental factors favouring the formation of surface wetness. Methanol may adsorb to or dissolve in this surface water and eventually be chemically or biologically removed from it. Management activities in agriculture and forestry are shown to increase local methanol emission by orders of magnitude; however, they are neglected at present in global budgets. While contemporary net land methanol budgets are overall consistent with the grand mean of the micrometeorological methanol flux measurements, we caution that the present approach of simulating methanol emission and deposition separately is prone to opposing systematic errors and does not allow for full advantage to be taken of

  11. An ecosystem-scale perspective of the net land methanol flux: synthesis of micrometeorological flux measurements

    NASA Astrophysics Data System (ADS)

    Wohlfahrt, G.; Amelynck, C.; Ammann, C.; Arneth, A.; Bamberger, I.; Goldstein, A. H.; Gu, L.; Guenther, A.; Hansel, A.; Heinesch, B.; Holst, T.; Hörtnagl, L.; Karl, T.; Laffineur, Q.; Neftel, A.; McKinney, K.; Munger, J. W.; Pallardy, S. G.; Schade, G. W.; Seco, R.; Schoon, N.

    2015-01-01

    Methanol is the second most abundant volatile organic compound in the troposphere and plays a significant role in atmospheric chemistry. While there is consensus about the dominant role of living plants as the major source and the reaction with OH as the major sink of methanol, global methanol budgets diverge considerably in terms of source/sink estimates reflecting uncertainties in the approaches used to model, and the empirical data used to separately constrain these terms. Here we compiled micrometeorological methanol flux data from eight different study sites and reviewed the corresponding literature in order to provide a first cross-site synthesis of the terrestrial ecosystem-scale methanol exchange and present an independent data-driven view of the land-atmosphere methanol exchange. Our study shows that the controls of plant growth on the production, and thus the methanol emission magnitude, and stomatal conductance on the hourly methanol emission variability, established at the leaf level, hold across sites at the ecosystem-level. Unequivocal evidence for bi-directional methanol exchange at the ecosystem scale is presented. Deposition, which at some sites even exceeds methanol emissions, represents an emerging feature of ecosystem-scale measurements and is likely related to environmental factors favouring the formation of surface wetness. Methanol may adsorb to or dissolve in this surface water and eventually be chemically or biologically removed from it. Management activities in agriculture and forestry are shown to increase local methanol emission by orders of magnitude; they are however neglected at present in global budgets. While contemporary net land methanol budgets are overall consistent with the grand mean of the micrometeorological methanol flux measurements, we caution that the present approach of simulating methanol emission and deposition separately is prone to opposing systematic errors and does not allow taking full advantage of the rich

  12. An ecosystem-scale perspective of the net land methanol flux: synthesis of micrometeorological flux measurements

    NASA Astrophysics Data System (ADS)

    Wohlfahrt, G.; Amelynck, C.; Ammann, C.; Arneth, A.; Bamberger, I.; Goldstein, A. H.; Gu, L.; Guenther, A.; Hansel, A.; Heinesch, B.; Holst, T.; Hörtnagl, L.; Karl, T.; Laffineur, Q.; Neftel, A.; McKinney, K.; Munger, J. W.; Pallardy, S. G.; Schade, G. W.; Seco, R.; Schoon, N.

    2015-07-01

    Methanol is the second most abundant volatile organic compound in the troposphere and plays a significant role in atmospheric chemistry. While there is consensus about the dominant role of living plants as the major source and the reaction with OH as the major sink of methanol, global methanol budgets diverge considerably in terms of source/sink estimates, reflecting uncertainties in the approaches used to model and the empirical data used to separately constrain these terms. Here we compiled micrometeorological methanol flux data from eight different study sites and reviewed the corresponding literature in order to provide a first cross-site synthesis of the terrestrial ecosystem-scale methanol exchange and present an independent data-driven view of the land-atmosphere methanol exchange. Our study shows that the controls of plant growth on production, and thus the methanol emission magnitude, as well as stomatal conductance on the hourly methanol emission variability, established at the leaf level, hold across sites at the ecosystem level. Unequivocal evidence for bi-directional methanol exchange at the ecosystem scale is presented. Deposition, which at some sites even exceeds methanol emissions, represents an emerging feature of ecosystem-scale measurements and is likely related to environmental factors favouring the formation of surface wetness. Methanol may adsorb to or dissolve in this surface water and eventually be chemically or biologically removed from it. Management activities in agriculture and forestry are shown to increase local methanol emission by orders of magnitude; however, they are neglected at present in global budgets. While contemporary net land methanol budgets are overall consistent with the grand mean of the micrometeorological methanol flux measurements, we caution that the present approach of simulating methanol emission and deposition separately is prone to opposing systematic errors and does not allow for full advantage to be taken of

  13. An ecosystem-scale perspective of the net land methanol flux: synthesis of micrometeorological flux measurements

    PubMed Central

    Wohlfahrt, G.; Amelynck, C.; Ammann, C.; Arneth, A.; Bamberger, I.; Goldstein, A. H.; Gu, L.; Guenther, A.; Hansel, A.; Heinesch, B.; Holst, T.; Hörtnagl, L.; Karl, T.; Laffineur, Q.; Neftel, A.; McKinney, K.; Munger, J. W.; Pallardy, S. G.; Schade, G. W.; Seco, R.; Schoon, N.

    2015-01-01

    Methanol is the second most abundant volatile organic compound in the troposphere and plays a significant role in atmospheric chemistry. While there is consensus about the dominant role of living plants as the major source and the reaction with OH as the major sink of methanol, global methanol budgets diverge considerably in terms of source/sink estimates reflecting uncertainties in the approaches used to model, and the empirical data used to separately constrain these terms. Here we compiled micrometeorological methanol flux data from eight different study sites and reviewed the corresponding literature in order to provide a first cross-site synthesis of the terrestrial ecosystem-scale methanol exchange and present an independent data-driven view of the land–atmosphere methanol exchange. Our study shows that the controls of plant growth on the production, and thus the methanol emission magnitude, and stomatal conductance on the hourly methanol emission variability, established at the leaf level, hold across sites at the ecosystem-level. Unequivocal evidence for bi-directional methanol exchange at the ecosystem scale is presented. Deposition, which at some sites even exceeds methanol emissions, represents an emerging feature of ecosystem-scale measurements and is likely related to environmental factors favouring the formation of surface wetness. Methanol may adsorb to or dissolve in this surface water and eventually be chemically or biologically removed from it. Management activities in agriculture and forestry are shown to increase local methanol emission by orders of magnitude; they are however neglected at present in global budgets. While contemporary net land methanol budgets are overall consistent with the grand mean of the micrometeorological methanol flux measurements, we caution that the present approach of simulating methanol emission and deposition separately is prone to opposing systematic errors and does not allow taking full advantage of the rich

  14. An ecosystem-scale perspective of the net land methanol flux: synthesis of micrometeorological flux measurements.

    PubMed

    Wohlfahrt, G; Amelynck, C; Ammann, C; Arneth, A; Bamberger, I; Goldstein, A H; Gu, L; Guenther, A; Hansel, A; Heinesch, B; Holst, T; Hörtnagl, L; Karl, T; Laffineur, Q; Neftel, A; McKinney, K; Munger, J W; Pallardy, S G; Schade, G W; Seco, R; Schoon, N

    2015-01-27

    Methanol is the second most abundant volatile organic compound in the troposphere and plays a significant role in atmospheric chemistry. While there is consensus about the dominant role of living plants as the major source and the reaction with OH as the major sink of methanol, global methanol budgets diverge considerably in terms of source/sink estimates reflecting uncertainties in the approaches used to model, and the empirical data used to separately constrain these terms. Here we compiled micrometeorological methanol flux data from eight different study sites and reviewed the corresponding literature in order to provide a first cross-site synthesis of the terrestrial ecosystem-scale methanol exchange and present an independent data-driven view of the land-atmosphere methanol exchange. Our study shows that the controls of plant growth on the production, and thus the methanol emission magnitude, and stomatal conductance on the hourly methanol emission variability, established at the leaf level, hold across sites at the ecosystem-level. Unequivocal evidence for bi-directional methanol exchange at the ecosystem scale is presented. Deposition, which at some sites even exceeds methanol emissions, represents an emerging feature of ecosystem-scale measurements and is likely related to environmental factors favouring the formation of surface wetness. Methanol may adsorb to or dissolve in this surface water and eventually be chemically or biologically removed from it. Management activities in agriculture and forestry are shown to increase local methanol emission by orders of magnitude; they are however neglected at present in global budgets. While contemporary net land methanol budgets are overall consistent with the grand mean of the micrometeorological methanol flux measurements, we caution that the present approach of simulating methanol emission and deposition separately is prone to opposing systematic errors and does not allow taking full advantage of the rich

  15. An ecosystem-scale perspective of the net land methanol flux. Synthesis of micrometeorological flux measurements

    DOE PAGES

    Wohlfahrt, G.; Amelynck, C.; Ammann, C.; ...

    2015-07-09

    Methanol is the second most abundant volatile organic compound in the troposphere and plays a significant role in atmospheric chemistry. While there is consensus about the dominant role of living plants as the major source and the reaction with OH as the major sink of methanol, global methanol budgets diverge considerably in terms of source/sink estimates, reflecting uncertainties in the approaches used to model and the empirical data used to separately constrain these terms. Here we compiled micrometeorological methanol flux data from eight different study sites and reviewed the corresponding literature in order to provide a first cross-site synthesis ofmore » the terrestrial ecosystem-scale methanol exchange and present an independent data-driven view of the land–atmosphere methanol exchange. Our study shows that the controls of plant growth on production, and thus the methanol emission magnitude, as well as stomatal conductance on the hourly methanol emission variability, established at the leaf level, hold across sites at the ecosystem level. Unequivocal evidence for bi-directional methanol exchange at the ecosystem scale is presented. Deposition, which at some sites even exceeds methanol emissions, represents an emerging feature of ecosystem-scale measurements and is likely related to environmental factors favouring the formation of surface wetness. Methanol may adsorb to or dissolve in this surface water and eventually be chemically or biologically removed from it. Management activities in agriculture and forestry are shown to increase local methanol emission by orders of magnitude; however, they are neglected at present in global budgets. While contemporary net land methanol budgets are overall consistent with the grand mean of the micrometeorological methanol flux measurements, we caution that the present approach of simulating methanol emission and deposition separately is prone to opposing systematic errors and does not allow for full advantage to be

  16. The toxicity of methanol

    SciTech Connect

    Tephly, T.R. )

    1991-01-01

    Methanol toxicity in humans and monkeys is characterized by a latent period of many hours followed by a metabolic acidosis and ocular toxicity. This is not observed in most lower animals. The metabolic acidosis and blindness is apparently due to formic acid accumulation in humans and monkeys, a feature not seen in lower animals. The accumulation of formate is due to a deficiency in formate metabolism which is, in turn, related, in part, to low hepatic tetrahydrofolate (H{sub 4}folate). An excellent correlation between hepatic H{sub 4} folate and formate oxidation rates has been shown within and across species. Thus, humans and monkeys possess low hepatic H{sub 4}folate levels, low rates of formate oxidation and accumulation of formate after methanol. Formate, itself, produces blindness in monkeys in the absence of metabolic acidosis. In addition to low hepatic H{sub 4}folate concentrations, monkeys and humans also have low hepatic 10-formyl H{sub 4}folate dehydrogenase levels, the enzyme which is the ultimate catalyst for conversion of formate to carbon dioxide. This review presents the basis for the role of folic acid-dependent reactions in the regulation of methanol toxicity.

  17. California methanol assessment. Volume 2: Technical report

    NASA Technical Reports Server (NTRS)

    Otoole, R.; Dutzi, E.; Gershman, R.; Heft, R.; Kalema, W.; Maynard, D.

    1983-01-01

    Energy feedstock sources for methanol; methanol and other synfuels; transport, storage, and distribution; air quality impact of methanol use in vehicles, chemical methanol production and use; methanol utilization in vehicles; methanol utilization in stationary applications; and environmental and regulatory constraints are discussed.

  18. Reduced methanol kinetic mechanisms for combustion applications

    SciTech Connect

    Yalamanchili, S.; Sirignano, W.A.; Seiser, R.; Seshadri, K.

    2005-08-01

    Reduced chemical kinetic mechanisms for methanol combustion were investigated by evaluating ignition delay magnitudes and combustion in a continuously stirred reactor. Unsteady computations were made to study the characteristics of the kinetic mechanisms proposed in the literature and to compare the dependence of various parameters on methanol combustion. All computations were done under isobaric conditions, and, to capture the influence of all the reactions involved in the mechanism, a very small time step was used. Finite-difference methods were used to solve the coupled differential equations. The five-step mechanism developed by C.M. Mueller and N. Peters [in: N. Peters, B. Rogg (Eds.), Reduced Kinetic Mechanisms for Applications in Combustion Systems, Springer-Verlag, New York, 1993, pp. 143-155] for premixed flames and both the five-step mechanism and the four-step mechanisms developed by C.M. Mueller, K. Seshadri, J.Y. Chen [ibid, pp. 284-307] for non-premixed flames were considered. It was found that the Mueller et al. five-step mechanism, with some modifications, best supported the spontaneous ignition and continuous stirred reactor combustion. The results were validated by comparing calculated ignition delays with available experimental data of C.T. Bowman [Combust. Flame 25 (1975) 343-354], and calculated final steady-state concentrations with chemical equilibrium calculations [J.-Y. Chen, Combust. Sci. Technol. 78 (1991) 127]. Initial temperature and concentration and the operating pressure of the system have a major effect on the delay of methanol ignition. The residence time of the continuous stirred reactor affects ignition delay and also changes the transient characteristic of chemical composition of the fuel-vapor mixture. The computations are intended to guide and explain many combustion studies that require a methanol kinetic mechanism.

  19. Formaldehyde, methanol and hydrocarbon emissions from methanol-fueled cars

    SciTech Connect

    Williams, R.L.; Lipari, F.; Potter, R.A. )

    1990-05-01

    Exhaust and evaporative emissions tests were conducted on several methanol- and gasoline-fueled vehicles. Separate samples for chromatographic analysis of formaldehyde, methanol, and individual hydrocarbons were collected in each of the three phases of the driving cycle and in each of the two portions of the evaporative emissions test. One vehicle, equipped with an experimental variable-fuel engine, was tested using methanol/gasoline fuel mixtures of 100, 85, 50, 15, and 0 percent methanol. Combustion-generated hydrocarbons were lowest using methanol fuel, and increased several-fold as the gasoline fraction was increased. Gasoline components in the exhaust increased from zero as the gasoline fraction of the fuel was increased. On the other hand, formaldehyde emissions were several times higher using methanol fuel than they were using gasoline. A dedicated methanol car and the variable-fuel car gave similar emissions patterns when they both were tested using methanol fuel. The organic-carbon composition of the exhaust was 85-90 percent methanol, 5-7 percent formaldehyde, and 3-9 percent hydrocarbons. Several cars that were tested using gasoline emitted similar distributions of hydrocarbons, even through the vehicles represented a broad range of current and developmental engine families and emissions control systems.

  20. Methanol-Air Batteries.

    DTIC Science & Technology

    1977-01-01

    Cells charged with 120 ml of anolyte , consisting of 6 M methanol in 11 M KOH, have operated for 2,230 hours under cyclic load drains of 50 mA for 13...minutes and 2 A for 1 second. One cell operated for more than 8,000 hours with periodic refilling of fresh anolyte , demonstrating the long serviceable...life of the electrode components. Fuel utilization efficiencies as high as 84% have been obtained from cells charged with an anolyte solution of

  1. Transport of methanol by pipeline

    SciTech Connect

    Not Available

    1985-04-01

    This report examines and evaluates the problems and considerations that could affect the feasibility of transporting methanol by pipeline. The following are the major conclusions: Though technical problems, such as methanol water contamination and materials incompatibility, remain to be solved, none appears insolvable. Methanol appears to be less toxic, and therefore to represent less of a health hazard, than gasoline, the fuel for which methanol is expected to substitute. The primary safety hazards of methanol, fire and explosion, are no worse than those of gasoline. The environmental hazards that can be associated with methanol are not as significant as those of petroleum. Provided quantities of throughput sufficient to justify pipeline transport are available, there appear to be no economic impediments to the transport of methanol by pipeline. Based on these, it appears that it can be concluded that the pipelining of methanol, whether via an existing petroleum pipeline or a new methanol-dedicated pipeline, is indeed feasible. 66 refs., 3 figs., 27 tabs.

  2. Methanol-reinforced kraft pulping

    SciTech Connect

    Norman, E.; Olm, L.; Teder, A. )

    1993-03-01

    The addition of methanol to a high-sulfidity kraft cook on Scandinavian softwood chips was studied under different process conditions. Delignification and the degradation of carbohydrates were accelerated, but the effect on delignification was greater. Thus, methanol addition improved selectivity. The positive effect of methanol could also be observed for modified kraft cooks having a leveled out alkali concentration and lower concentration of sodium ions and dissolved lignin at the end of the cook. Methanol addition had no discernible effect on pulp strength or on pulp bleachability.

  3. Effects of methanol on a methanol-tolerant bacterial lipase.

    PubMed

    Santambrogio, Carlo; Sasso, Francesco; Natalello, Antonino; Brocca, Stefania; Grandori, Rita; Doglia, Silvia Maria; Lotti, Marina

    2013-10-01

    Methanol is often employed in biocatalysis with the purpose of increasing substrates solubility or as the acyl acceptor in transesterification reactions, but inhibitory effects are observed in several cases. We have studied the influence of methanol on the catalytic activity and on the conformation of the lipase from Burkholderia glumae, which is reported to be highly methanol tolerant if compared with other lipases. We detected highest activity in the presence of 50-70 % methanol. Under these conditions, however, the enzyme stability is perturbed, leading to gradual protein unfolding and finally to aggregation. These results surmise that, for this lipase, methanol-induced deactivation does not depend on inhibition of catalytic activity but rather on negative effects on the conformational stability of the catalyst.

  4. OTEC energy via methanol production

    SciTech Connect

    Avery, W.H.; Richards, D.; Niemeyer, W.G.; Shoemaker, J.D.

    1983-01-01

    The conceptual design of an 160 MW/sub e/ OTEC plantship has been documented; it is designed to produce 1000 tonne/day of fuel-grade methanol from coal slurry shipped to the plantship, using oxygen and hydrogen from the on-board electrolysis of water. Data and components are used that were derived by Brown and Root Development, Inc. (BARDI) in designing a barge-mounted plant to make methanol from natural gas for Litton Industries and in the design and construction of a coal-to-ammonia demonstration plant in operation at Muscle Shoals, Alabama, for the Tennessee Valley Authority (TVA). The OTEC-methanol plant design is based on the use of the Texaco gasifier and Lurgi synthesis units. The sale price of OTEC methanol delivered to port from this first-of-a-kind plant is estimated to be marginally competitive with methanol from other sources at current market prices.

  5. California methanol assessment. Volume 1: Summary report

    NASA Technical Reports Server (NTRS)

    Otoole, R.; Dutzi, E.; Gershman, R.; Heft, R.; Kalema, W.; Maynard, D.

    1983-01-01

    The near term methanol industry, the competitive environment, long term methanol market, the transition period, air quality impacts of methanol, roles of the public and private sectors are considered.

  6. A simple preparation of very high methanol tolerant cathode electrocatalyst for direct methanol fuel cell based on polymer-coated carbon nanotube/platinum

    PubMed Central

    Yang, Zehui; Nakashima, Naotoshi

    2015-01-01

    The development of a durable and methanol tolerant electrocatalyst with a high oxygen reduction reaction activity is highly important for the cathode side of direct methanol fuel cells. Here, we describe a simple and novel methodology to fabricate a practically applicable electrocatalyst with a high methanol tolerance based on poly[2,2′-(2,6-pyridine)-5,5′-bibenzimidazole]-wrapped multi-walled carbon nanotubes, on which Pt nanoparticles have been deposited, then coated with poly(vinylphosphonic acid) (PVPA). The polymer coated electrocatalyst showed an ~3.3 times higher oxygen reduction reaction activity compared to that of the commercial CB/Pt and methanol tolerance in the presence of methanol to the electrolyte due to a 50% decreased methanol adsorption on the Pt after coating with the PVPA. Meanwhile, the peroxide generation of the PVPA coated electrocatalyst was as low as 0.8% with 2 M methanol added to the electrolyte, which was much lower than those of the non-PVPA-coated electrocatalyst (7.5%) and conventional CB/Pt (20.5%). Such a high methanol tolerance is very important for the design of a direct methanol fuel cell cathode electrocatalyst with a high performance. PMID:26192397

  7. Single passive direct methanol fuel cell supplied with pure methanol

    NASA Astrophysics Data System (ADS)

    Feng, Ligang; Zhang, Jing; Cai, Weiwei; Liang, Liang; Xing, Wei; Liu, Changpeng

    2011-03-01

    A new single passive direct methanol fuel cell (DMFC) supplied with pure methanol is designed, assembled and tested using a pervaporation membrane (PM) to control the methanol transport. The effect of the PM size on the fuel cell performances and the constant current discharge of the fuel cell with one-fueling are studied. The results show that the fuel cell with PM 9 cm2 can yield a maximum power density of about 21 mW cm-2, and a stable performances at a discharge current of 100 mA can last about 45 h. Compared with DMFC supplied with 3 M methanol solution, the energy density provided by this new DMFC has increased about 6 times.

  8. A bottom-up perspective of the net land methanol flux: synthesis of global eddy covariance flux measurements

    NASA Astrophysics Data System (ADS)

    Wohlfahrt, Georg; Amelynck, Crist; Ammann, Christof; Arneth, Almut; Bamberger, Ines; Goldstein, Allen; Hansel, Armin; Heinesch, Bernhard; Holst, Thomas; Hörtnagl, Lukas; Karl, Thomas; Neftel, Albrecht; McKinney, Karena; Munger, William; Schade, Gunnar; Schoon, Niels

    2014-05-01

    Methanol (CH3OH) is, after methane, the second most abundant VOC in the troposphere and globally represents nearly 20% of the total biospheric VOC emissions. With typical concentrations of 1-10 ppb in the continental boundary layer, methanol plays a crucial role in atmospheric chemistry, which needs to be evaluated in the light of ongoing changes in land use and climate. Previous global methanol budgets have approached the net land flux by summing up the various emission terms (namely primary biogenic and anthropogenic emissions, plant decay and biomass burning) and by subtracting dry and wet deposition, resulting in a net land flux in the range of 75-245 Tg y-1. The data underlying these budget calculations largely stem from small-scale leaf gas exchange measurements and while recently column-integrated remotely sensed methanol concentrations have become available for constraining budget calculations, there have been few attempts to contrast model calculations with direct net ecosystem-scale methanol flux measurements. Here we use eddy covariance methanol flux measurements from 8 sites in Europe and North America to study the magnitude of and controls on the diurnal and seasonal variability in the net ecosystem methanol flux. In correspondence with leaf-level literature, our data show that methanol emission and its strong environmental and biotic control (by temperature and stomatal conductance) prevailed at the more productive (agricultural) sites and at a perturbed forest site. In contrast, at more natural, less productive sites substantial deposition of methanol occurred, in particular during periods of surface wetness. These deposition processes are poorly represented by currently available temperature/light and/or production-driven modelling algorithms. A new framework for modelling the bi-directional land-atmosphere methanol exchange is proposed which accounts for the production of methanol in leaves, the regulation of leaf methanol emission by stomatal

  9. Methanol crossover in direct methanol fuel cell systems.

    SciTech Connect

    Pivovar, B. S.; Bender, G.; Davey, J. R.; Zelenay, P.

    2003-01-01

    Direct methanol fuel cells (DMFCs) are currently being investigated for a number of different applications from several milliwatts to near kilowatt size scales (cell phones, laptops, auxiliary power units, etc .). Because methanol has a very high energy density, over 6000 W hr/kg, a DMFC can possibly have greatly extended lifetimes compared to the batteries, doesn't present the storage problems associated with hydrogen fuel cells and can possibly operate more efficiently and cleanly than internal combustion engines.

  10. Methanol Oxidation on Pt3Sn(111) for Direct Methanol Fuel Cells: Methanol Decomposition.

    PubMed

    Lu, Xiaoqing; Deng, Zhigang; Guo, Chen; Wang, Weili; Wei, Shuxian; Ng, Siu-Pang; Chen, Xiangfeng; Ding, Ning; Guo, Wenyue; Wu, Chi-Man Lawrence

    2016-05-18

    PtSn alloy, which is a potential material for use in direct methanol fuel cells, can efficiently promote methanol oxidation and alleviate the CO poisoning problem. Herein, methanol decomposition on Pt3Sn(111) was systematically investigated using periodic density functional theory and microkinetic modeling. The geometries and energies of all of the involved species were analyzed, and the decomposition network was mapped out to elaborate the reaction mechanisms. Our results indicated that methanol and formaldehyde were weakly adsorbed, and the other derivatives (CHxOHy, x = 1-3, y = 0-1) were strongly adsorbed and preferred decomposition rather than desorption on Pt3Sn(111). The competitive methanol decomposition started with the initial O-H bond scission followed by successive C-H bond scissions, (i.e., CH3OH → CH3O → CH2O → CHO → CO). The Brønsted-Evans-Polanyi relations and energy barrier decomposition analyses identified the C-H and O-H bond scissions as being more competitive than the C-O bond scission. Microkinetic modeling confirmed that the vast majority of the intermediates and products from methanol decomposition would escape from the Pt3Sn(111) surface at a relatively low temperature, and the coverage of the CO residue decreased with an increase in the temperature and decrease in partial methanol pressure.

  11. Methanol unity frays, discounting returns

    SciTech Connect

    Morris, G.D.L.

    1997-02-05

    This article reviews the price variation in methanol for February 1997 and how the company Methanex compares to other producers. The discrepancy between posting prices and transaction prices is noted.

  12. Acute methanol toxicity in minipigs

    SciTech Connect

    Dorman, D.C.; Dye, J.A.; Nassise, M.P.; Ekuta, J.; Bolon, B.

    1993-01-01

    The pig has been proposed as a potential animal model for methanol-induced neuro-ocular toxicosis in humans because of its low liver tetrahydrofolate levels and slower rate of formate metabolism compared to those of humans. To examine the validity of this animal model, 12 4-month-old female minipigs (minipig YU) were given a single oral dose of water or methanol at 1.0, 2.5, or 5.0 g/kg body wt by gavage (n = 3 pigs/dose). Dose-dependent signs of acute methanol intoxication, which included mild CNS depression, tremors, ataxia, and recumbency, developed within 0.5 to 2.0 hr, and resolved by 52 hr. Methanol- and formate-dosed pigs did not develop optic nerve lesions, toxicologically significant formate accumulation, or metabolic acidosis. Based on results following a single dose, female minipigs do not appear to be overtly sensitive to methanol and thus may not be a suitable animal model for acute methanol-induced neuroocular toxicosis.

  13. Indonesia to build methanol plant

    SciTech Connect

    Alperowicz, N.

    1992-08-05

    P.T. Kaltim Methanol Industri (Jakarta), a company set up to build a new methanol plant in Indonesia, expects to award contracts for the construction of a new plant, Indonesia's second methanol unit, by the end of this year. P.T. Kaltim Methanol is a private company owned by P.T. Humpuss, an industrial group active in transport, airlines, and shipping of LNG and methanol. The 2,000-m.t./day plant will be built at Bontang, Kalimantan Island, close to the fertilizer producer P.T. Pupuk Kaltim and near the country's largest natural gas reserves. The site is also a deepsea port, handy for transportation of ready product. Three groups are in discussions with the investor on plant supply as well as methanol offtake deals. They are H G/Kockner; John Brown/Davy/Lucky Goldstar, offering the ICI process independently; and Lurgi/Metallgesellschaft (MG), proposing the Lurgi process. At least 60% of the output is expected to be exported, and both ICI and MG are understood to be interested in selling product from the future plant. Japan, Southeast Asia, and the US are targeted.

  14. Reduction of methanol crossover by thin cracked metal barriers at the interface between membrane and electrode in direct methanol fuel cells

    NASA Astrophysics Data System (ADS)

    Kim, Sungjun; Jang, Segeun; Kim, Sang Moon; Ahn, Chi-Yeong; Hwang, Wonchan; Cho, Yong-Hun; Sung, Yung-Eun; Choi, Mansoo

    2017-09-01

    This work reports the successful reduction in methanol crossover by creating a thin cracked metal barrier at the interface between a Nafion® membrane and an electrode in direct methanol fuel cells (DMFCs). The cracks are generated by simple mechanical stretching of a metal deposited Nafion® membrane as a result of the elastic mismatch between the two attached surfaces. The cracked metal barriers with varying strains (∼0.5 and ∼1.0) are investigated and successfully incorporated into the DMFC. Remarkably, the membrane electrode assembly with the thin metal crack exhibits comparable ohmic resistance as well as reduction of methanol crossover, which enhanced the device performance.

  15. Unusual case of methanol poisoning

    SciTech Connect

    Shapiro, L.; Henderson, M. . Dept. of Chemical Pathology); Madi, S.; Mellor, L. . Dept. of Medicine, and Pharmacy)

    1993-01-09

    A 31-year-old man with a history of alcohol abuse presented to the accident and emergency department complaining of blurred vision. 4 h previously he had drunk 300 mL de-icer fluid. Electrolytes, urea, creatinine, glucose, and blood-gas analysis were normal. Measured osmolality, however, was 368 mosmol/kg with a calculated osmolality of 300 mosmol/kg, which indicated a greatly increased osmolar gap. He was therefore given 150 mL whisky and admitted. Methanol was later reported as 200 mg/dL. Ethylene glycol was not detected, but another glycol, propylene glycol, was present at 47 mg/dL. 10 h after ingestion an intravenous infusion of ethanol was started and he was hemodialysed for 7 h. After dialysis he was given a further 100 mL whisky and the rate of ethanol infusion was reduced to 11 g per h. Methanol and ethanol were measured twice daily until methanol was under 10/mg/dL: The recommendation is that blood ethanol be maintained between 100 and 200 mg/dL during treatment of methanol poisoning. This concentration was not achieved, presumably because of the high rate of ethanol metabolism often found in alcoholics. Antifreeze solutions commonly contain methanol and ethylene glycol. Sometimes propylene glycol is substituted because it has properties similar to those of ethylene glycol but is less toxic. The authors postulate that propylene glycol inhibited the metabolism of methanol in the patient, thus sparing him from the toxic effects of methanol.

  16. Rapid starting methanol reactor system

    DOEpatents

    Chludzinski, Paul J.; Dantowitz, Philip; McElroy, James F.

    1984-01-01

    The invention relates to a methanol-to-hydrogen cracking reactor for use with a fuel cell vehicular power plant. The system is particularly designed for rapid start-up of the catalytic methanol cracking reactor after an extended shut-down period, i.e., after the vehicular fuel cell power plant has been inoperative overnight. Rapid system start-up is accomplished by a combination of direct and indirect heating of the cracking catalyst. Initially, liquid methanol is burned with a stoichiometric or slightly lean air mixture in the combustion chamber of the reactor assembly. The hot combustion gas travels down a flue gas chamber in heat exchange relationship with the catalytic cracking chamber transferring heat across the catalyst chamber wall to heat the catalyst indirectly. The combustion gas is then diverted back through the catalyst bed to heat the catalyst pellets directly. When the cracking reactor temperature reaches operating temperature, methanol combustion is stopped and a hot gas valve is switched to route the flue gas overboard, with methanol being fed directly to the catalytic cracking reactor. Thereafter, the burner operates on excess hydrogen from the fuel cells.

  17. Methanol conversion to higher hydrocarbons

    SciTech Connect

    Tabak, S.A.

    1994-12-31

    Several indirect options exist for producing chemicals and transportation fuels from coal, natural gas, or biomass. All involve an initial conversion step to synthesis gas (CO and H{sub 2}). Presently, there are two commercial technologies for converting syngas to liquids: Fischer-Tropsch, which yields a range of aliphatic hydrocarbons with molecular weights determined by Schulz-Flory kinetics, and methanol synthesis. Mobil`s diversity of technology for methanol conversion gives the methanol synthesis route flexibility for production of either gasoline, distillate or chemicals. Mobil`s ZSM-5 catalyst is the key in several processes for producing chemicals and transportation fuels from methanol: MTO for light olefins, MTG for gasoline, MOGD for distillates. The MTG process has been commercialized in New Zealand since 1985, producing one-third of the country`s gasoline supply, while MTO and MOGD have been developed and demonstrated at greater than 100 BPD scale. This paper will discuss recent work in understanding methanol conversion chemistry and the various options for its use.

  18. Fabrication and Characterization of a Micro Methanol Sensor Using the CMOS-MEMS Technique

    PubMed Central

    Fong, Chien-Fu; Dai, Ching-Liang; Wu, Chyan-Chyi

    2015-01-01

    A methanol microsensor integrated with a micro heater manufactured using the complementary metal oxide semiconductor (CMOS)-microelectromechanical system (MEMS) technique was presented. The sensor has a capability of detecting low concentration methanol gas. Structure of the sensor is composed of interdigitated electrodes, a sensitive film and a heater. The heater located under the interdigitated electrodes is utilized to provide a working temperature to the sensitive film. The sensitive film prepared by the sol-gel method is tin dioxide doped cadmium sulfide, which is deposited on the interdigitated electrodes. To obtain the suspended structure and deposit the sensitive film, the sensor needs a post-CMOS process to etch the sacrificial silicon dioxide layer and silicon substrate. The methanol senor is a resistive type. A readout circuit converts the resistance variation of the sensor into the output voltage. The experimental results show that the methanol sensor has a sensitivity of 0.18 V/ppm. PMID:26512671

  19. Fabrication and Characterization of a Micro Methanol Sensor Using the CMOS-MEMS Technique.

    PubMed

    Fong, Chien-Fu; Dai, Ching-Liang; Wu, Chyan-Chyi

    2015-10-23

    A methanol microsensor integrated with a micro heater manufactured using the complementary metal oxide semiconductor (CMOS)-microelectromechanical system (MEMS) technique was presented. The sensor has a capability of detecting low concentration methanol gas. Structure of the sensor is composed of interdigitated electrodes, a sensitive film and a heater. The heater located under the interdigitated electrodes is utilized to provide a working temperature to the sensitive film. The sensitive film prepared by the sol-gel method is tin dioxide doped cadmium sulfide, which is deposited on the interdigitated electrodes. To obtain the suspended structure and deposit the sensitive film, the sensor needs a post-CMOS process to etch the sacrificial silicon dioxide layer and silicon substrate. The methanol senor is a resistive type. A readout circuit converts the resistance variation of the sensor into the output voltage. The experimental results show that the methanol sensor has a sensitivity of 0.18 V/ppm.

  20. Photoionization of methanol and formaldehyde

    NASA Technical Reports Server (NTRS)

    Warneck, P.

    1971-01-01

    Photoions produced in methanol and formaldehyde by radiation in the spectral region 450-1150 A were analyzed mass spectrometrically, and their relative yields were determined as a function of wavelength. First ionization potentials were determined, and the ion yield curves were interpreted in terms of ionization processes in conjunction with other data. Fragment ions were detected on mass numbers of 31, 30, 29, 15, and 14 for methanol, and 29, 2, and 1 for formaldehyde. The associated appearance potentials were determined and were used to calculate heats of formation of the ions CH2OH(+) and HCO(+), and the radicals CH3, CH2, and HCO.

  1. Spontaneous pneumothorax in weightlifters.

    PubMed

    Marnejon, T; Sarac, S; Cropp, A J

    1995-06-01

    Spontaneous pneumothorax is infrequently caused by strenuous exertion. To our knowledge there has only been one case of spontaneous pneumothorax associated with weightlifting reported in the medical literature. We describe three consecutive cases of spontaneous pneumothorax associated with weightlifting. We postulate that spontaneous pneumothorax in these patients may be secondary to improper breathing techniques. It is important that physicians and weight trainers be aware of the association between weight lifting and spontaneous pneumothorax and assure that proper instruction is given to athletes who work with weights.

  2. Air Breathing Direct Methanol Fuel Cell

    DOEpatents

    Ren; Xiaoming

    2003-07-22

    A method for activating a membrane electrode assembly for a direct methanol fuel cell is disclosed. The method comprises operating the fuel cell with humidified hydrogen as the fuel followed by running the fuel cell with methanol as the fuel.

  3. Fatal methanol poisoning: features of liver histopathology.

    PubMed

    Akhgari, Maryam; Panahianpour, Mohammad Hadi; Bazmi, Elham; Etemadi-Aleagha, Afshar; Mahdavi, Amirhosein; Nazari, Saeed Hashemi

    2013-03-01

    Methanol poisoning has become a considerable problem in Iran. Liver can show some features of poisoning after methanol ingestion. Therefore, our concern was to examine liver tissue histopathology in fatal methanol poisoning cases in Iranian population. In this study, 44 cases of fatal methanol poisoning were identified in a year. The histological changes of the liver were reviewed. The most striking features of liver damage by light microscopy were micro-vesicular steatosis, macro-vesicular steatosis, focal hepatocyte necrosis, mild intra-hepatocyte bile stasis, feathery degeneration and hydropic degeneration. Blood and vitreous humor methanol concentrations were examined to confirm the proposed history of methanol poisoning. The majority of cases were men (86.36%). In conclusion, methanol poisoning can cause histological changes in liver tissues. Most importantly in cases with mean blood and vitreous humor methanol levels greater than 127 ± 38.9 mg/dL more than one pathologic features were detected.

  4. Spontaneous EEG activity and spontaneous emotion regulation.

    PubMed

    Tortella-Feliu, M; Morillas-Romero, A; Balle, M; Llabrés, J; Bornas, X; Putman, P

    2014-12-01

    Variability in both frontal and parietal spontaneous EEG activity, using α and β band power and θ/β and δ/β ratios, was explored in a sample of 96 healthy volunteers as a potential correlate of individual differences in spontaneous emotion regulation (SER). Following a baseline EEG recording, participants were asked to continuously rate their discomfort while looking at affective pictures, as well as for a period of time after exposure. Greater spontaneous β band power in parietal locations, lower frontal and parietal δ/β ratios, and lower parietal θ/β ratio were associated with lower ratings of discomfort after the offset of unpleasant pictures. Moreover, lower parietal δ/β ratio was also related to less time needed to recover from discomfort after exposure to aversive pictures, while only a greater frontal and parietal α band power appeared to be associated with faster recovery from discomfort induced by normative-neutral pictures. However, parietal δ/β ratio was the only predictor of both minimum discomfort ratings and time needed to downregulate following exposure to unpleasant pictures, and frontal α band power the only spontaneous EEG index that predicted variability in spontaneous down-regulation after the exposure to normative-neutral pictures. Results are discussed focusing on the utility of diverse spontaneous EEG measures in several cortical regions when capturing trait-like individual differences in emotion regulation capabilities and processes. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Enhanced methanol utilization in direct methanol fuel cell

    DOEpatents

    Ren, Xiaoming; Gottesfeld, Shimshon

    2001-10-02

    The fuel utilization of a direct methanol fuel cell is enhanced for improved cell efficiency. Distribution plates at the anode and cathode of the fuel cell are configured to distribute reactants vertically and laterally uniformly over a catalyzed membrane surface of the fuel cell. A conductive sheet between the anode distribution plate and the anodic membrane surface forms a mass transport barrier to the methanol fuel that is large relative to a mass transport barrier for a gaseous hydrogen fuel cell. In a preferred embodiment, the distribution plate is a perforated corrugated sheet. The mass transport barrier may be conveniently increased by increasing the thickness of an anode conductive sheet adjacent the membrane surface of the fuel cell.

  6. Fermentation of methanol in the sheep rumen.

    PubMed

    Pol, A; Demeyer, D I

    1988-03-01

    Sheep fed a hay-concentrate diet were adapted to pectin administration and ruminal infusion of methanol. Both treatments resulted in a strong increase in the rate of methanogenesis from methanol. Quantitative data show that methanol was exclusively converted into methane. Treatments did not influence ruminal volatile fatty acid percentages.

  7. Air breathing direct methanol fuel cell

    DOEpatents

    Ren, Xiaoming

    2002-01-01

    An air breathing direct methanol fuel cell is provided with a membrane electrode assembly, a conductive anode assembly that is permeable to air and directly open to atmospheric air, and a conductive cathode assembly that is permeable to methanol and directly contacting a liquid methanol source.

  8. Methanol production method and system

    DOEpatents

    Chen, Michael J.; Rathke, Jerome W.

    1984-01-01

    Ethanol is selectively produced from the reaction of methanol with carbon monoxide and hydrogen in the presence of a transition metal carbonyl catalyst. Methanol serves as a solvent and may be accompanied by a less volatile co-solvent. The solution includes the transition metal carbonyl catalysts and a basic metal salt such as an alkali metal or alkaline earth metal formate, carbonate or bicarbonate. A gas containing a high carbon monoxide to hydrogen ratio, as is present in a typical gasifer product, is contacted with the solution for the preferential production of ethanol with minimal water as a byproduct. Fractionation of the reaction solution provides substantially pure ethanol product and allows return of the catalysts for reuse.

  9. The direct methanol fuel cell

    SciTech Connect

    Halpert, G.; Narayanan, S.R.; Frank, H.

    1995-08-01

    This presentation describes the approach and progress in the ARPA-sponsored effort to develop a Direct Methanol, Liquid-Feed Fuel Cell (DMLFFC) with a solid Polymer Electrolyte Membrane (PEM) for battery replacement in small portable applications. Using Membrane Electrode Assemblies (MEAs) developed by JPL and Giner, significant voltage was demonstrated at relatively high current densities. The DMLFFC utilizes a 3 percent aqueous solution of methanol that is oxidized directly in the anode (fuel) chamber and oxygen (air) in the cathode chamber to produce water and significant power. The only products are water and CO{sub 2}. The ARPA effort is aimed at replacing the battery in the BA 5590 military radio.

  10. Heterogeneous Chemistry Involving Methanol in Tropospheric Clouds

    NASA Technical Reports Server (NTRS)

    Tabazadeh, A.; Yokelson, R. J.; Singh, H. B.; Hobbs, P. V.; Crawford, J. H.; Iraci, L. T.

    2004-01-01

    In this report we analyze airborne measurements to suggest that methanol in biomass burning smoke is lost heterogeneously in clouds. When a smoke plume intersected a cumulus cloud during the SAFARI 2000 field project, the observed methanol gas phase concentration rapidly declined. Current understanding of gas and aqueous phase chemistry cannot explain the loss of methanol documented by these measurements. Two plausible heterogeneous reactions are proposed to explain the observed simultaneous loss and production of methanol and formaldehyde, respectively. If the rapid heterogeneous processing of methanol, seen in a cloud impacted by smoke, occurs in more pristine clouds, it could affect the oxidizing capacity of the troposphere on a global scale.

  11. Heterogeneous Chemistry Involving Methanol in Tropospheric Clouds

    NASA Technical Reports Server (NTRS)

    Tabazadeh, A.; Yokelson, R. J.; Singh, H. B.; Hobbs, P. V.; Crawford, J. H.; Iraci, L. T.

    2004-01-01

    In this report we analyze airborne measurements to suggest that methanol in biomass burning smoke is lost heterogeneously in clouds. When a smoke plume intersected a cumulus cloud during the SAFARI 2000 field project, the observed methanol gas phase concentration rapidly declined. Current understanding of gas and aqueous phase chemistry cannot explain the loss of methanol documented by these measurements. Two plausible heterogeneous reactions are proposed to explain the observed simultaneous loss and production of methanol and formaldehyde, respectively. If the rapid heterogeneous processing of methanol, seen in a cloud impacted by smoke, occurs in more pristine clouds, it could affect the oxidizing capacity of the troposphere on a global scale.

  12. Direct methanol fuel cell and system

    DOEpatents

    Wilson, Mahlon S.

    2004-10-26

    A fuel cell having an anode and a cathode and a polymer electrolyte membrane located between anode and cathode gas diffusion backings uses a methanol vapor fuel supply. A permeable polymer electrolyte membrane having a permeability effective to sustain a carbon dioxide flux equivalent to at least 10 mA/cm.sup.2 provides for removal of carbon dioxide produced at the anode by reaction of methanol with water. Another aspect of the present invention includes a superabsorpent polymer material placed in proximity to the anode gas diffusion backing to hold liquid methanol or liquid methanol solution without wetting the anode gas diffusion backing so that methanol vapor from the liquid methanol or liquid methanol-water solution is supplied to the membrane.

  13. The toxicity of inhaled methanol vapors

    SciTech Connect

    Kavet, R.; Nauss, K.M. )

    1990-01-01

    Methanol could become a major automotive fuel in the U.S., and its use may result in increased exposure of the public to methanol vapor. Nearly all of the available information on methanol toxicity in humans relates to the consequences of acute, rather than chronic, exposures. Acute methanol toxicity evolves in a well-understood pattern and consists of an uncompensated metabolic acidosis with superimposed toxicity to the visual system. The toxic properties of methanol are rooted in the factors that govern both the conversion of methanol to formic acid and the subsequent metabolism of formate to carbon dioxide in the folate pathway. In short, the toxic syndrome sets in if formate generation continues at a rate that exceeds its rate of metabolism. Current evidence indicates that formate accumulation will not challenge the metabolic capacity of the folate pathway at the anticipated levels of exposure to automotive methanol vapor.117 references.

  14. Trinidad to build fifth methanol plant

    SciTech Connect

    1997-04-09

    Lurgi confirms it has been awarded a lump sum turnkey contract to build Trinidad`s fifth methanol plant. The facility will be owned by Titan Methanol, whose shareholders are Beacon Group Energy Investment Fund (75%) Amoco Chemical (15%), and Saturn Methanol (10%). The 2,500-m.t./day unit at Point Lisas, which is scheduled to come onstream at the end of 1999, will be Trinidad`s largest methanol unit. Saturn Methanol will be responsible for methanol offtake. Lurgi will use its combined reforming process for the gas section of the unit and its low-pressure methanol synthesis technology. Lurgi has used the same processes in plants in Malaysia and Indonesia.

  15. Sol-gel based silica electrodes for inorganic membrane direct methanol fuel cells

    NASA Astrophysics Data System (ADS)

    Kim, Hyea; Kohl, Paul A.

    Inorganic glass electrodes are of interest for use with inorganic proton exchange membranes for direct methanol fuel cells. Platinum-ruthenium glass electrodes (PtRu/C-SiO 2) have been prepared by incorporating the PtRu/C nanoparticles into a silica-based matrix. The SiO 2 matrix was synthesized through the sol-gel reaction of 3-(trihydroxysilyl)-1-propanesulfonic acid (3TPS) and 3-glycidoxypropyltrimethoxysilane (GPTMS). The distribution of the PtRu/C particles can be controlled by changing the properties of the gel matrix. The effect of gelation time, mole fraction of reactants within the sol, curing temperature, and glass ionomer content were investigated. The adhesion of the catalyst layer on the membrane, catalytic activity for methanol oxidation, and inhibition of methanol permeation through the membrane have been characterized and optimized. The electroless deposition of PtRu onto the PtRu/C nanoparticles was performed to increase the sheet conductivity of the electrode. It was found that the electrolessly deposited metal improved the catalytic activity for methanol oxidation and decreased the methanol cross-over. The methanol fuel cell performance using the inorganic membrane electrode assembly was 236 μA cm -2 at 0.4 V and was stable for more than 10 days.

  16. Methanol-Tolerant Platinum-Palladium Catalyst Supported on Nitrogen-Doped Carbon Nanofiber for High Concentration Direct Methanol Fuel Cells

    PubMed Central

    Kim, Jiyoung; Jang, Jin-Sung; Peck, Dong-Hyun; Lee, Byungrok; Yoon, Seong-Ho; Jung, Doo-Hwan

    2016-01-01

    Pt-Pd catalyst supported on nitrogen-doped carbon nanofiber (N-CNF) was prepared and evaluated as a cathode electrode of the direct methanol fuel cell (DMFC). The N-CNF, which was directly synthesized by the catalytic chemical vapor deposition from acetonitrile at 640 °C, was verified as having a change of electrochemical surface properties such as oxygen reduction reaction (ORR) activities and the electrochemical double layer compared with common carbon black (CB). To attain the competitive oxygen reduction reaction activity with methanol tolerance, the Pt and Pd metals were supported on the CB or the N-CNF. The physical and electrochemical characteristics of the N-CNF–supported Pt-Pd catalyst were examined and compared with catalyst supported on the CB. In addition, DMFC single cells using these catalysts as the cathode electrode were applied to obtain I-V polarization curves and constant current operating performances with high-concentration methanol as the fuel. Pt-Pd catalysts had obvious ORR activity even in the presence of methanol. The higher power density was obtained at all the methanol concentrations when it applied to the membrane electrode assembly (MEA) of the DMFC. When the N-CNF is used as the catalyst support material, a better performance with high-concentration methanol is expected. PMID:28335275

  17. Methanol-Tolerant Platinum-Palladium Catalyst Supported on Nitrogen-Doped Carbon Nanofiber for High Concentration Direct Methanol Fuel Cells.

    PubMed

    Kim, Jiyoung; Jang, Jin-Sung; Peck, Dong-Hyun; Lee, Byungrok; Yoon, Seong-Ho; Jung, Doo-Hwan

    2016-08-15

    Pt-Pd catalyst supported on nitrogen-doped carbon nanofiber (N-CNF) was prepared and evaluated as a cathode electrode of the direct methanol fuel cell (DMFC). The N-CNF, which was directly synthesized by the catalytic chemical vapor deposition from acetonitrile at 640 °C, was verified as having a change of electrochemical surface properties such as oxygen reduction reaction (ORR) activities and the electrochemical double layer compared with common carbon black (CB). To attain the competitive oxygen reduction reaction activity with methanol tolerance, the Pt and Pd metals were supported on the CB or the N-CNF. The physical and electrochemical characteristics of the N-CNF-supported Pt-Pd catalyst were examined and compared with catalyst supported on the CB. In addition, DMFC single cells using these catalysts as the cathode electrode were applied to obtain I-V polarization curves and constant current operating performances with high-concentration methanol as the fuel. Pt-Pd catalysts had obvious ORR activity even in the presence of methanol. The higher power density was obtained at all the methanol concentrations when it applied to the membrane electrode assembly (MEA) of the DMFC. When the N-CNF is used as the catalyst support material, a better performance with high-concentration methanol is expected.

  18. Metabolic methanol: molecular pathways and physiological roles.

    PubMed

    Dorokhov, Yuri L; Shindyapina, Anastasia V; Sheshukova, Ekaterina V; Komarova, Tatiana V

    2015-04-01

    Methanol has been historically considered an exogenous product that leads only to pathological changes in the human body when consumed. However, in normal, healthy individuals, methanol and its short-lived oxidized product, formaldehyde, are naturally occurring compounds whose functions and origins have received limited attention. There are several sources of human physiological methanol. Fruits, vegetables, and alcoholic beverages are likely the main sources of exogenous methanol in the healthy human body. Metabolic methanol may occur as a result of fermentation by gut bacteria and metabolic processes involving S-adenosyl methionine. Regardless of its source, low levels of methanol in the body are maintained by physiological and metabolic clearance mechanisms. Although human blood contains small amounts of methanol and formaldehyde, the content of these molecules increases sharply after receiving even methanol-free ethanol, indicating an endogenous source of the metabolic methanol present at low levels in the blood regulated by a cluster of genes. Recent studies of the pathogenesis of neurological disorders indicate metabolic formaldehyde as a putative causative agent. The detection of increased formaldehyde content in the blood of both neurological patients and the elderly indicates the important role of genetic and biochemical mechanisms of maintaining low levels of methanol and formaldehyde. Copyright © 2015 the American Physiological Society.

  19. Endogenous Methanol Regulates Mammalian Gene Activity

    PubMed Central

    Komarova, Tatiana V.; Petrunia, Igor V.; Shindyapina, Anastasia V.; Silachev, Denis N.; Sheshukova, Ekaterina V.; Kiryanov, Gleb I.; Dorokhov, Yuri L.

    2014-01-01

    We recently showed that methanol emitted by wounded plants might function as a signaling molecule for plant-to-plant and plant-to-animal communications. In mammals, methanol is considered a poison because the enzyme alcohol dehydrogenase (ADH) converts methanol into toxic formaldehyde. However, the detection of methanol in the blood and exhaled air of healthy volunteers suggests that methanol may be a chemical with specific functions rather than a metabolic waste product. Using a genome-wide analysis of the mouse brain, we demonstrated that an increase in blood methanol concentration led to a change in the accumulation of mRNAs from genes primarily involved in detoxification processes and regulation of the alcohol/aldehyde dehydrogenases gene cluster. To test the role of ADH in the maintenance of low methanol concentration in the plasma, we used the specific ADH inhibitor 4-methylpyrazole (4-MP) and showed that intraperitoneal administration of 4-MP resulted in a significant increase in the plasma methanol, ethanol and formaldehyde concentrations. Removal of the intestine significantly decreased the rate of methanol addition to the plasma and suggested that the gut flora may be involved in the endogenous production of methanol. ADH in the liver was identified as the main enzyme for metabolizing methanol because an increase in the methanol and ethanol contents in the liver homogenate was observed after 4-MP administration into the portal vein. Liver mRNA quantification showed changes in the accumulation of mRNAs from genes involved in cell signalling and detoxification processes. We hypothesized that endogenous methanol acts as a regulator of homeostasis by controlling the mRNA synthesis. PMID:24587296

  20. Towards a methanol economy based on homogeneous catalysis: methanol to H2 and CO2 to methanol.

    PubMed

    Alberico, E; Nielsen, M

    2015-04-21

    The possibility to implement both the exhaustive dehydrogenation of aqueous methanol to hydrogen and CO2 and the reverse reaction, the hydrogenation of CO2 to methanol and water, may pave the way to a methanol based economy as part of a promising renewable energy system. Recently, homogeneous catalytic systems have been reported which are able to promote either one or the other of the two reactions under mild conditions. Here, we review and discuss these developments.

  1. Design and Operation of an Electrochemical Methanol Concentration Sensor for Direct Methanol Fuel Cell Systems

    NASA Technical Reports Server (NTRS)

    Narayanan, S. R.; Valdez, T. I.; Chun, W.

    2000-01-01

    The development of a 150-Watt packaged power source based on liquid feed direct methanol fuel cells is being pursued currently at the Jet propulsion Laboratory for defense applications. In our studies we find that the concentration of methanol in the fuel circulation loop affects the electrical performance and efficiency the direct methanol fuel cell systems significantly. The practical operation of direct methanol fuel cell systems, therefore, requires accurate monitoring and control of methanol concentration. The present paper reports on the principle and demonstration of an in-house developed electrochemical sensor suitable for direct methanol fuel cell systems.

  2. Design and Operation of an Electrochemical Methanol Concentration Sensor for Direct Methanol Fuel Cell Systems

    NASA Technical Reports Server (NTRS)

    Narayanan, S. R.; Valdez, T. I.; Chun, W.

    2000-01-01

    The development of a 150-Watt packaged power source based on liquid feed direct methanol fuel cells is being pursued currently at the Jet propulsion Laboratory for defense applications. In our studies we find that the concentration of methanol in the fuel circulation loop affects the electrical performance and efficiency the direct methanol fuel cell systems significantly. The practical operation of direct methanol fuel cell systems, therefore, requires accurate monitoring and control of methanol concentration. The present paper reports on the principle and demonstration of an in-house developed electrochemical sensor suitable for direct methanol fuel cell systems.

  3. Recent Studies on Methanol Crossover in Liquid-Feed Direct Methanol Fuel Cells

    NASA Technical Reports Server (NTRS)

    Valdez, T. I.; Narayanan, S. R.

    2000-01-01

    In this work, the effects of methanol crossover and airflow rates on the cathode potential of an operating direct methanol fuel cell are explored. Techniques for quantifying methanol crossover in a fuel cell and for separating the electrical performance of each electrode in a fuel cell are discussed. The effect of methanol concentration on cathode potential has been determined to be significant. The cathode is found to be mass transfer limited when operating on low flow rate air and high concentrations of methanol. Improvements in cathode structure and operation at low methanol concentration have been shown to result in improved cell performance.

  4. BP-sterling methanol startup

    SciTech Connect

    Cornitius, T.

    1996-11-27

    BP chemicals ceased being the only major acetic acid maker without a captive feedstock source late last month when its 150-million gal/year methanol joint venture with Sterling Chemicals came onstream at Texas City, TX. Most of the new plant`s output will feed Sterling`s 800-million lbs/year on-site acid plant; the rest will feed BP`s acetic production elsewhere or be sold in the merchant market. BP already markets all Sterling`s acetic acid production and holds an equity position in the acetic acid unit, the company says. Acetic acid producers are still smarting from their last failed attempt to increase prices, which foundered because anticipated strengthening in vinyl acetate monomer (VAM) did not occur. Based on their overconfidence in VAM, acetic acid sellers nominated higher third-quarter prices in the Far East then the market could bear. Customers balked and contracts settled lower than expected. The price slipped again in the fourth quarter. The US acetic acid market has been tight since the Hoechst Celanese outage at Clear Lake, TX last April, when sellers started pushing prices globally. Quantum also recently restarted its acetic acid complex at Deer Park, TX after a 60-day outage. The Far East is a global indicator and heavily influences other markets, analysts say. Third-quarter price increases in Europe did not go through, and fourth-quarter contracts stay flat at $560-$580/m.t. Prices are at about $500/m.t. in Taiwan and Korea. US producers saw third-quarter contracts edge up to 23 cts-25 cts/lb. Although the BP methanol plant will not be a big merchant seller, it does return some existing volumes to the market. Methanol has been firming in the fourth quarter, after a weak first half. Supplies worldwide are tight.

  5. The Effects Of Methanol On The Trapping Of Volatile Ice Components

    NASA Astrophysics Data System (ADS)

    Brown, Wendy; Burke, D.

    2012-05-01

    Icy mantle evaporation gives the rich chemistry observed around hot cores. Water ice is the dominant component of many astrophysical ices and this has motivated studies to identify the sublimation of volatile ice components when water-rich ices are heated. Most investigations focus on binary ices, with water as the main component. To understand thermal processing of real astrophysical ices, the current laboratory definition of these ices needs to be extended. Methanol is important in this regard, due to its close association with water. It is typically the second most abundant species and the most abundant organic molecule detected in cometary comae, interstellar ices and on a variety of bodies at the edge of our solar system. Methanol abundance varies depending on the environment, ranging from as low as 5% with respect to water in dark clouds, to approximately 30% near low and high mass proto-stars. With this in mind, we present an investigation of the adsorption and desorption of interstellar ices, showing the effect of methanol on the trapping and release of volatiles from water-rich ices. OCS and CO2 are used as probe molecules since they reside in water and methanol-rich environments. Experiments show that OCS thermal desorption depends on ice morphology and composition. Data suggest that OCS is incorporated into amorphous water ice during heating, as a result of morphological changes in the ice, and it then explosively desorbs as the water crystallises. Similar effects are observed for OCS deposited on/within methanol ice. In contrast, OCS desorption from mixed water/methanol ices is complex. Desorption occurs at the onset of methanol desorption, in addition to co-desorption with crystalline water. Hence co-depositing impurities, e.g. methanol, with water ice significantly alters the desorption dynamics of volatiles. These results are of interest as they can be used to model star formation.

  6. Methods of conditioning direct methanol fuel cells

    DOEpatents

    Rice, Cynthia; Ren, Xiaoming; Gottesfeld, Shimshon

    2005-11-08

    Methods for conditioning the membrane electrode assembly of a direct methanol fuel cell ("DMFC") are disclosed. In a first method, an electrical current of polarity opposite to that used in a functioning direct methanol fuel cell is passed through the anode surface of the membrane electrode assembly. In a second method, methanol is supplied to an anode surface of the membrane electrode assembly, allowed to cross over the polymer electrolyte membrane of the membrane electrode assembly to a cathode surface of the membrane electrode assembly, and an electrical current of polarity opposite to that in a functioning direct methanol fuel cell is drawn through the membrane electrode assembly, wherein methanol is oxidized at the cathode surface of the membrane electrode assembly while the catalyst on the anode surface is reduced. Surface oxides on the direct methanol fuel cell anode catalyst of the membrane electrode assembly are thereby reduced.

  7. An Experimental Study of Methanol Reformation.

    DTIC Science & Technology

    1979-12-01

    1973, p. 1300) show how methanol compares to other alterna- tives. In addition, the production of methanol from syngas is a proven commercial...technology, and the syngas can be coal-derived (Wilk 1978, p. 56). The disadvantages of methanol concern the fact that more will have to be carried than...the chief engineer’s job to continue research and upgrading into 1980. 2.2 Design Parameters The following limitations were placed on the new system

  8. Direct methanol fuel cell for portable applications

    SciTech Connect

    Valdez, T.I.; Narayanan, S.R.; Frank, H.; Chun, W.

    1997-12-01

    A five cell direct methanol fuel cell stack has been developed at the Jet Propulsion Laboratory. Presently direct methanol fuel cell technology is being incorporated into a system for portable applications. Electrochemical performance and its dependence on flow rate and temperature for a five cell stack are presented. Water transport data, and water transport mechanisms for direct methanol fuel cells are discussed. Stack response to pulse loads has been characterized. Implications of stack performance and operating conditions on system design have been addressed.

  9. Method of steam reforming methanol to hydrogen

    DOEpatents

    Beshty, Bahjat S.

    1990-01-01

    The production of hydrogen by the catalyzed steam reforming of methanol is accomplished using a reformer of greatly reduced size and cost wherein a mixture of water and methanol is superheated to the gaseous state at temperatures of about 800.degree. to about 1,100.degree. F. and then fed to a reformer in direct contact with the catalyst bed contained therein, whereby the heat for the endothermic steam reforming reaction is derived directly from the superheated steam/methanol mixture.

  10. Air breathing direct methanol fuel cell

    DOEpatents

    Ren, Xiaoming; Gottesfeld, Shimshon

    2002-01-01

    An air breathing direct methanol fuel cell is provided with a membrane electrode assembly, a conductive anode assembly that is permeable to air and directly open to atmospheric air, and a conductive cathode assembly that is permeable to methanol and directly contacting a liquid methanol source. Water loss from the cell is minimized by making the conductive cathode assembly hydrophobic and the conductive anode assembly hydrophilic.

  11. Methanol incorporation in clathrate hydrates and the implications for oil and gas pipeline flow assurance and icy planetary bodies.

    PubMed

    Shin, Kyuchul; Udachin, Konstantin A; Moudrakovski, Igor L; Leek, Donald M; Alavi, Saman; Ratcliffe, Christopher I; Ripmeester, John A

    2013-05-21

    One of the best-known uses of methanol is as antifreeze. Methanol is used in large quantities in industrial applications to prevent methane clathrate hydrate blockages from forming in oil and gas pipelines. Methanol is also assigned a major role as antifreeze in giving icy planetary bodies (e.g., Titan) a liquid subsurface ocean and/or an atmosphere containing significant quantities of methane. In this work, we reveal a previously unverified role for methanol as a guest in clathrate hydrate cages. X-ray diffraction (XRD) and NMR experiments showed that at temperatures near 273 K, methanol is incorporated in the hydrate lattice along with other guest molecules. The amount of included methanol depends on the preparative method used. For instance, single-crystal XRD shows that at low temperatures, the methanol molecules are hydrogen-bonded in 4.4% of the small cages of tetrahydrofuran cubic structure II hydrate. At higher temperatures, NMR spectroscopy reveals a number of methanol species incorporated in hydrocarbon hydrate lattices. At temperatures characteristic of icy planetary bodies, vapor deposits of methanol, water, and methane or xenon show that the presence of methanol accelerates hydrate formation on annealing and that there is unusually complex phase behavior as revealed by powder XRD and NMR spectroscopy. The presence of cubic structure I hydrate was confirmed and a unique hydrate phase was postulated to account for the data. Molecular dynamics calculations confirmed the possibility of methanol incorporation into the hydrate lattice and show that methanol can favorably replace a number of methane guests.

  12. Methanol incorporation in clathrate hydrates and the implications for oil and gas pipeline flow assurance and icy planetary bodies

    PubMed Central

    Shin, Kyuchul; Udachin, Konstantin A.; Moudrakovski, Igor L.; Leek, Donald M.; Alavi, Saman; Ratcliffe, Christopher I.; Ripmeester, John A.

    2013-01-01

    One of the best-known uses of methanol is as antifreeze. Methanol is used in large quantities in industrial applications to prevent methane clathrate hydrate blockages from forming in oil and gas pipelines. Methanol is also assigned a major role as antifreeze in giving icy planetary bodies (e.g., Titan) a liquid subsurface ocean and/or an atmosphere containing significant quantities of methane. In this work, we reveal a previously unverified role for methanol as a guest in clathrate hydrate cages. X-ray diffraction (XRD) and NMR experiments showed that at temperatures near 273 K, methanol is incorporated in the hydrate lattice along with other guest molecules. The amount of included methanol depends on the preparative method used. For instance, single-crystal XRD shows that at low temperatures, the methanol molecules are hydrogen-bonded in 4.4% of the small cages of tetrahydrofuran cubic structure II hydrate. At higher temperatures, NMR spectroscopy reveals a number of methanol species incorporated in hydrocarbon hydrate lattices. At temperatures characteristic of icy planetary bodies, vapor deposits of methanol, water, and methane or xenon show that the presence of methanol accelerates hydrate formation on annealing and that there is unusually complex phase behavior as revealed by powder XRD and NMR spectroscopy. The presence of cubic structure I hydrate was confirmed and a unique hydrate phase was postulated to account for the data. Molecular dynamics calculations confirmed the possibility of methanol incorporation into the hydrate lattice and show that methanol can favorably replace a number of methane guests. PMID:23661058

  13. SnS2 Thin Film Deposition by Spray Pyrolysis

    NASA Astrophysics Data System (ADS)

    Jaber, Abdallah Yahia; Alamri, Saleh Noaiman; Aida, Mohammed Salah

    2012-06-01

    Tin disulfide (SnS2) thin films have been synthesized using a simplified spray pyrolysis technique using a perfume atomizer. The films were deposited using two different solutions prepared by the dilution of SnCl2 and thiourea in distilled water and in methanol. The obtained films have a microcrystalline structure. The film deposited using methanol as the solvent is nearly stochiometric SnS2 with a spinel phase having a (001) preferential orientation. The film prepared with an aqueous solution is Sn-rich. Scanning electronic microscopy (SEM) images reveal that the film deposited with the aqueous solution is rough and is formed with large wires. However, the film deposited with methanol is dense and smooth. Conductivity measurements indicate that the aqueous solution leads to an n-type semiconductor, while methanol leads to a p-type semiconductor.

  14. Determination of methanol in Iranian herbal distillates.

    PubMed

    Shirani, Kobra; Hassani, Faezeh Vahdati; Azar-Khiavi, Kamal Razavi; Moghaddam, Zohreh Samie; Karimi, Gholamreza

    2016-06-01

    Herbal distillates have been used as beverages, for flavoring, or as phytomedicines in many countries for a long time. Recently, the occurrence of blindness after drinking herbal distillates has created concerns in Iran. The aim of this study was to determine the concentrations of methanol in herbal distillates produced in Iran. Eighty-four most commonly used herbal distillates purchased from herbal distillate factories were analyzed for methanol contents by gas chromatography and flame ionization detection, with ethanol as internal standard. In 15 herbal distillates, the methanol concentration was below the limit of quantitation. The methanol concentrations in all samples ranged from 43 to 277 mg/L. Forty-five samples contained methanol in excess of the Iranian standard. The maximum concentration was found in an herbal distillate of Mentha piperita (factory E) (277±12), and the minimum in a distillate of Carum carvi (factory B) (42.6 ± 0.5). Since the 45 Iranian herbal distillates containing methanol levels were beyond the legal limits according to the Iranian standard, it seems necessary to monitor the amount of methanol and give a warning to watch out for the latent risk problem of methanol uptake, and establish a definitive relationship between the degree of intoxication observed and the accumulation of methanol in the blood.

  15. Spontaneous Resolution of Massive Spontaneous Tubercular Pneumothorax

    PubMed Central

    Kant, Surya; Saheer, S.; Hassan, G.; Parengal, Jabeed

    2011-01-01

    A 29-year-old female presented with complaints of fever and productive cough of three weeks duration. Pulmonary tuberculosis was diagnosed bacteriologically and she was prescribed antituberculosis drugs. During follow-up she developed massive pneumothorax, for which patient refused surgical management and was managed conservatively. After six months there was complete spontaneous resolution of pneumothorax. The unusual presentation and unexpected outcome prompted us to report this case. PMID:22937428

  16. Spontaneous Coronary Artery Dissection

    MedlinePlus

    ... artery dissection (SCAD). It's not yet clear what role these factors play in causing the disease. Common factors include: Female sex. Though spontaneous coronary artery dissection (SCAD) can occur ...

  17. Biogeochemical Cycle of Methanol in Anoxic Deep-Sea Sediments.

    PubMed

    Yanagawa, Katsunori; Tani, Atsushi; Yamamoto, Naoya; Hachikubo, Akihiro; Kano, Akihiro; Matsumoto, Ryo; Suzuki, Yohey

    2016-06-25

    The biological flux and lifetime of methanol in anoxic marine sediments are largely unknown. We herein reported, for the first time, quantitative methanol removal rates in subsurface sediments. Anaerobic incubation experiments with radiotracers showed high rates of microbial methanol consumption. Notably, methanol oxidation to CO2 surpassed methanol assimilation and methanogenesis from CO2/H2 and methanol. Nevertheless, a significant decrease in methanol was not observed after the incubation, and this was attributed to the microbial production of methanol in parallel with its consumption. These results suggest that microbial reactions play an important role in the sources and sinks of methanol in subseafloor sediments.

  18. Spontaneous combustion of hydrogen

    NASA Technical Reports Server (NTRS)

    Nusselt, Wilhelm; Pothmann, PH

    1923-01-01

    It is shown by the author's experiments that hydrogen which escapes to the atmosphere through openings in the system may burn spontaneously if it contains dust. Purely thermal reasoning can not account for the combustion. It seems to be rather an electrical ignition. In order to determine whether the cause of the spontaneous ignition was thermo-chemical, thermo-mechanical, or thermo-electrical, the experiments in this paper were performed.

  19. Resonance Raman spectrum of the solvated electron in methanol: simulation within a cluster model.

    PubMed

    Neumann, Stefanie; Eisfeld, Wolfgang; Sobolewski, Andrzej L; Domcke, Wolfgang

    2006-05-04

    The microsolvation of the CH(3)OH(2) hypervalent radical in methanol clusters has been investigated by density functional theory. It is shown that the CH(3)OH(2) radical spontaneously decomposes within methanol clusters into protonated methanol and a localized solvated electron cloud. The geometric and electronic structures of these clusters as well as their vibrational frequencies have been characterized. Resonance Raman intensities, associated with the s --> p transition of the unpaired electron, have been estimated for CH(3)OH(2)M(n) (M = CH(3)OH, n = 1-3) clusters. It is shown that with increasing cluster size the simulated spectra converge toward the resonance Raman spectrum of the solvated electron in methanol measured recently by Tauber and Mathies (J. Am. Chem. Soc. 2004, 126, 3414). The results suggest that CH(3)OH(2)M(n) clusters are useful finite-size model systems for the computational investigation of the spectroscopic properties of the solvated electron in liquid methanol.

  20. Developmental and Reproductive Toxicology of Methanol

    EPA Science Inventory

    Methanol is a high production volume chemical used as a feedstock for chemical syntheses and as a solvent and fuel additive. Methanol is acutely toxic to humans, causing acidosis, blindness in death at high dosages, but its developmental and reproductive toxicity in humans is poo...

  1. Antidote review: fomepizole for methanol poisoning.

    PubMed

    Mycyk, Mark B; Leikin, Jerrold B

    2003-01-01

    Fomepizole (Antizol) was recently approved by the US Food and Drug Administration for treatment of methanol poisoning. By inhibiting the hepatic enzyme alcohol dehydrogenase, it presents formation of toxic metabolites with far fewer consequences than traditional ethanol therapy. It appears that fomepizole will become standard therapy for methanol intoxication as it is for ethylene glycol poisoning.

  2. Methanol Steam Reforming for Hydrogen Production

    SciTech Connect

    Palo, Daniel R.; Dagle, Robert A.; Holladay, Jamie D.

    2007-09-11

    Review article covering developments in methanol steam reforming in the context of PEM fuel cell power systems. Subjects covered include methanol background, use, and production, comparison to other fuels, power system considerations, militrary requirements, competing technologies, catalyst development, and reactor and system development and demonstration.

  3. Developmental and Reproductive Toxicology of Methanol

    EPA Science Inventory

    Methanol is a high production volume chemical used as a feedstock for chemical syntheses and as a solvent and fuel additive. Methanol is acutely toxic to humans, causing acidosis, blindness in death at high dosages, but its developmental and reproductive toxicity in humans is poo...

  4. The platinum-catalyzed decomposition of methanol: A deceptive demonstration

    SciTech Connect

    Coffing, D.L.; Wile, J.L. )

    1993-07-01

    The platinum-catalyzed gas-phase decomposition of methanol can be used for classroom demonstration in an exciting, interesting fashion. The platinum catalysts, after being heated until it glows, can be made to continue glowing for hours by suspending it over the methanol. This demonstration is useful in a classroom setting for several reasons. First it is more complicated than it appears initially, involving a reaction that is not immediately obvious and is, therefore, more challenging for students to understand. Second, the platinum illustrates the phenomenon of exothermic reactions in a distinctive and memorable way. Because the platinum foil has to be heated before the reactions will proceed, this demonstration also is a perfect example of the temperature dependence of [Delta]G in determining the spontaneity of a reaction. Finally, this demonstration can be used to explain the mutual interaction of two reactions. Because an explanation of this demonstration requires the use of many chemical concepts, it is an ideal activity for stimulating synthesis among students near the end of the course.

  5. Thin Film Catalyst Layers for Direct Methanol Fuel Cells

    NASA Technical Reports Server (NTRS)

    Witham, C. K.; Chun, W.; Ruiz, R.; Valdez, T. I.; Narayanan, S. R.

    2000-01-01

    One of the primary obstacles to the widespread use of the direct methanol fuel cell (DMFC) is the high cost of the catalyst. Therefore, reducing the catalyst loading well below the current level of 8-12 mg/cm 2 would be important to commercialization. The current methods for preparation of catalyst layers consisting of catalyst, ionomer and sometimes a hydrophobic additive are applied by either painting, spraying, decal transfer or screen printing processes. Sputter deposition is a coating technique widely used in manufacturing and therefore particularly attractive. In this study we have begun to explore sputtering as a method for catalyst deposition. Present experiments focus on Pt-Ru catalyst layers for the anode.

  6. Microbial methanol uptake in northeast Atlantic waters

    PubMed Central

    Dixon, Joanna L; Beale, Rachael; Nightingale, Philip D

    2011-01-01

    Methanol is the predominant oxygenated volatile organic compound in the troposphere, where it can significantly influence the oxidising capacity of the atmosphere. However, we do not understand which processes control oceanic concentrations, and hence, whether the oceans are a source or a sink to the atmosphere. We report the first methanol loss rates in seawater by demonstrating that 14C-labelled methanol can be used to determine microbial uptake into particulate biomass, and oxidation to 14CO2. We have found that methanol is used predominantly as a microbial energy source, but also demonstrated its use as a carbon source. We report biological methanol oxidation rates between 2.1 and 8.4 nmol l−1 day−1 in surface seawater of the northeast Atlantic. Kinetic experiments predict a Vmax of up to 29 nmol l−1 day−1, with a high affinity Km constant of 9.3 n in more productive coastal waters. We report surface concentrations of methanol in the western English channel of 97±8 n (n=4) between May and June 2010, and for the wider temperate North Atlantic waters of 70±13 n (n=6). The biological turnover time of methanol has been estimated between 7 and 33 days, although kinetic experiments suggest a 7-day turnover in more productive shelf waters. Methanol uptake rates into microbial particles significantly correlated with bacterial and phytoplankton parameters, suggesting that it could be used as a carbon source by some bacteria and possibly some mixotrophic eukaryotes. Our results provide the first methanol loss rates from seawater, which will improve the understanding of the global methanol budget. PMID:21068775

  7. Spontaneous closure of stoma.

    PubMed

    Pandit, Narendra; Singh, Harjeet; Kumar, Hemanth; Gupta, Rajesh; Verma, G R

    2016-11-01

    Intestinal loop stoma is a common surgical procedure performed for various benign and malignant abdominal problems, but it rarely undergoes spontaneous closure, without surgical intervention. Two male patients presented to our emergency surgical department with acute abdominal pain. One of them was diagnosed as having rectosigmoid perforation and underwent diversion sigmoid loop colostomy after primary closure of the perforation. The other was a known case of carcinoma of the rectum who had already undergone low anterior resection with covering loop ileostomy; the patient underwent second loop ileostomy, this time for complicated intestinal obstruction. To our surprise, both the loop colostomy and ileostomy closed spontaneously at 8 weeks and 6 weeks, respectively, without any consequences. Spontaneous stoma closure is a rare and interesting event. The exact etiology for spontaneous closure remains unknown, but it may be hypothesized to result from slow retraction of the stoma, added to the concept of a tendency towards spontaneous closure of enterocutaneous fistula. © The Author(s) 2015. Published by Oxford University Press and the Digestive Science Publishing Co. Limited.

  8. Spontaneous Perforation of Pyometra

    PubMed Central

    Yildizhan, Begüm; Uyar, Esra; Şişmanoğlu, Alper; Güllüoğlu, Gülfem; Kavak, Zehra N.

    2006-01-01

    Pyometra is the accumulation of purulent material in the uterine cavity. Its reported incidence is 0.01−0.5% in gynecologic patients; however, as far as elderly patients are concerned, its incidence is 13.6% [3]. The most common cause of pyometra is malignant diseases of genital tract and the consequences of their treatment (radiotherapy). Other causes are benign tumors like leiomyoma, endometrial polyps, senile cervicitis, cervical occlusion after surgery, puerperal infections, and congenital cervical anomalies. Spontaneous rupture of the uterus is an extremely rare complication of pyometra. To our knowledge, only 21 cases of spontaneous perforation of pyometra have been reported in English literature since 1980. This paper reports an additional case of spontaneous uterine rupture. PMID:17093350

  9. Biomodal spontaneous fission

    SciTech Connect

    Hulet, E.K. )

    1989-09-26

    Investigations of mass and kinetic-energy distributions from spontaneous fission have been extended in recent years to an isotope of element 104 and, for half-lives, to an isotope of element 108. The results have been surprising in that spontaneous fission half-lives have turned out to be much longer than expected and mass and kinetic- energy distributions were found to abruptly shift away from those of the lighter actinides, showing two modes of fission. These new developments have caused a re-evaluation of our understanding of the fission process, bringing an even deeper appreciation of the role played by nuclear shell effects upon spontaneous fission properties. 16 refs., 10 figs.

  10. Engineering Escherichia coli for methanol conversion.

    PubMed

    Müller, Jonas E N; Meyer, Fabian; Litsanov, Boris; Kiefer, Patrick; Potthoff, Eva; Heux, Stéphanie; Quax, Wim J; Wendisch, Volker F; Brautaset, Trygve; Portais, Jean-Charles; Vorholt, Julia A

    2015-03-01

    Methylotrophic bacteria utilize methanol and other reduced one-carbon compounds as their sole source of carbon and energy. For this purpose, these bacteria evolved a number of specialized enzymes and pathways. Here, we used a synthetic biology approach to select and introduce a set of "methylotrophy genes" into Escherichia coli based on in silico considerations and flux balance analysis to enable methanol dissimilation and assimilation. We determined that the most promising approach allowing the utilization of methanol was the implementation of NAD-dependent methanol dehydrogenase and the establishment of the ribulose monophosphate cycle by expressing the genes for hexulose-6-phosphate synthase (Hps) and 6-phospho-3-hexuloisomerase (Phi). To test for the best-performing enzymes in the heterologous host, a number of enzyme candidates from different donor organisms were selected and systematically analyzed for their in vitro and in vivo activities in E. coli. Among these, Mdh2, Hps and Phi originating from Bacillus methanolicus were found to be the most effective. Labeling experiments using (13)C methanol with E. coli producing these enzymes showed up to 40% incorporation of methanol into central metabolites. The presence of the endogenous glutathione-dependent formaldehyde oxidation pathway of E. coli did not adversely affect the methanol conversion rate. Taken together, the results of this study represent a major advancement towards establishing synthetic methylotrophs by gene transfer.

  11. Capacity additions ease tight methanol supply

    SciTech Connect

    Greek, B.F. )

    1988-10-03

    Two menthanol plants now in operation - one in the U.S., the other in Chile - will boost global supplies of methanol more than 375 million gal annually. This large capacity addition and smaller expansions in other parts of the world will exceed demand growth during 1988 and 1989, easing the squeeze on supplies. As the result of increased supplies, methanol prices could slip slightly in the fourth quarter. They are more likely to decline next year, however. The two plants, which started up in August, are owned and operated by Tenneco Oil Co. Processing and Marketing and by Cape Horn Methanol (CHM). The Tenneco plant, located in Pasadena, Tex., was restarted after a shutdown in 1982 when prices for methanol were low. It now is running at full capacity of 125 million gal per year. The plant uses the low-pressure process technology of Lurgi, reportedly requiring for feedstock and energy between 100,000 and 125,000 cu ft of methane per gallon. Global trade in methanol smooths out the supply and demand inconsistencies. Surging methanol demand in the U.S. and in Western Europe has been met by imports from areas where methanol production is most economical - that is, where natural gas is readily available and has no other application as high in value. Canada, Chile, and Trinidad are examples of those areas.

  12. Spontaneous sarcomere dynamics

    NASA Astrophysics Data System (ADS)

    Günther, Stefan; Kruse, Karsten

    2010-12-01

    Sarcomeres are the basic force generating units of striated muscles and consist of an interdigitating arrangement of actin and myosin filaments. While muscle contraction is usually triggered by neural signals, which eventually set myosin motors into motion, isolated sarcomeres can oscillate spontaneously between a contracted and a relaxed state. We analyze a model for sarcomere dynamics, which is based on a force-dependent detachment rate of myosin from actin. Our numerical bifurcation analysis of the spontaneous sarcomere dynamics reveals notably Hopf bifurcations, canard explosions, and gluing bifurcations. We discuss possible implications for experiments.

  13. Spontaneous bilateral tubal pregnancy.

    PubMed

    Wali, Aisha Syed; Khan, Rozilla Sadia

    2012-02-01

    With the increase in incidence of ectopic pregnancy over the decades, bilateral ectopic pregnancy is also increasing. It is usually associated with assisted reproductive techniques (ART) but in recent years few cases of spontaneous bilateral ectopic pregnancy have been reported. Gynaecologists should be aware of this and that ultrasonography has limitations in diagnosis. In cases of ectopic pregnancy where contralateral adnexa is not clearly identified on ultrasound and fertility needs to be conserved, patient should be managed by experts in well equipped centres. A case of spontaneous bilateral tubal pregnancy that remained undiagnosed till laparotomy, is described.

  14. Advanced direct methanol fuel cells. Final report

    SciTech Connect

    Hamdan, Monjid; Kosek, John A.

    1999-11-01

    The goal of the program was an advanced proton-exchange membrane (PEM) for use as the electrolyte in a liquid feed direct methanol fuel cell which provides reduced methanol crossover while simultaneously providing high conductivity and low membrane water content. The approach was to use a membrane containing precross-linked fluorinated base polymer films and subsequently to graft the base film with selected materials. Over 80 different membranes were prepared. The rate of methanol crossover through the advanced membranes was reduced 90%. A 5-cell stack provided stable performance over a 100-hour life test. Preliminary cost estimates predicted a manufacturing cost at $4 to $9 per kW.

  15. Global methanol overcapacity will get worse

    SciTech Connect

    Anderson, E.V.

    1983-06-20

    The world methanol situation, characterized by an excess of 21% over demand in 1983, is expected to worsen by 1985 when a 29% excess is anticipated. Canada will suffer the most for its overly optimistic projections of methanol's use in fuel. The areas of greatest supply surplus, the US (at least until 1988), Canada, Mexico, Eastern Europe, and the Africa-Middle East region, are expected to compete fiercely for business in the biggest deficit areas of the Pacific Basin, Southeast Asia, and Western Europe. Several factors could turn the grim situation around: financial incentives for using methanol and sucess of the new method of converting methenol directly to gasoline. 3 figures.

  16. Ion-Ice Astrochemistry: Barrierless Low-Energy Deposition Pathways to HCOOH, CH3OH, and CO2 on Icy Grain Mantles from Precursor Cations

    NASA Technical Reports Server (NTRS)

    Woon, David E.

    2011-01-01

    A new family of very favorable reaction pathways is explored involving the deposition of ions on icy grain mantles with very low energies. Quantum chemical cluster calculations at the MP2/6-31+G** level in 4H2O clusters and at the B3LYP/6-31+G** level in 17H2O clusters indicate that HCO+ and CH3 + are able to react spontaneously with one of the water molecules in the cluster to form protonated formic acid (HCOOH2 +) and protonated methanol (CH3OH2 +), respectively. It is furthermore found that these initial adducts spontaneously transfer their excess protons to the cluster to form neutral formic acid and methanol, plus solvated hydronium, H3O+. In the final case, if a CO molecule is bound to the surface of the cluster, OH+ may react with it to form protonated carbon dioxide (HCO2 +), which then loses its proton to yield CO2 and H3O+. In the present model, all of these processes were found to occur with no barriers. Discussion includes the analogous gas phase processes, which have been considered in previous studies, as well as the competitive abstraction pathway for HCO(+) + H2O.

  17. Ion-Ice Astrochemistry: Barrierless Low-Energy Deposition Pathways to HCOOH, CH3OH, and CO2 on Icy Grain Mantles from Precursor Cations

    NASA Technical Reports Server (NTRS)

    Woon, David E.

    2011-01-01

    A new family of very favorable reaction pathways is explored involving the deposition of ions on icy grain mantles with very low energies. Quantum chemical cluster calculations at the MP2/6-31+G** level in 4H2O clusters and at the B3LYP/6-31+G** level in 17H2O clusters indicate that HCO+ and CH3 + are able to react spontaneously with one of the water molecules in the cluster to form protonated formic acid (HCOOH2 +) and protonated methanol (CH3OH2 +), respectively. It is furthermore found that these initial adducts spontaneously transfer their excess protons to the cluster to form neutral formic acid and methanol, plus solvated hydronium, H3O+. In the final case, if a CO molecule is bound to the surface of the cluster, OH+ may react with it to form protonated carbon dioxide (HCO2 +), which then loses its proton to yield CO2 and H3O+. In the present model, all of these processes were found to occur with no barriers. Discussion includes the analogous gas phase processes, which have been considered in previous studies, as well as the competitive abstraction pathway for HCO(+) + H2O.

  18. Spontaneous polyploidization in cucumber

    USDA-ARS?s Scientific Manuscript database

    Cucumber occasionally produces polyploid plants, which are problematic for growers because these plants produce misshaped fruits with non-viable seeds. In this study, we undertook the first quantitative study to estimate the frequency of spontaneous polyploids in cucumber. Seeds of recombinant inbre...

  19. Spontaneous rib fractures.

    PubMed

    Katrancioglu, Ozgur; Akkas, Yucel; Arslan, Sulhattin; Sahin, Ekber

    2015-07-01

    Other than trauma, rib fracture can occur spontaneously due to a severe cough or sneeze. In this study, patients with spontaneous rib fractures were analyzed according to age, sex, underlying pathology, treatment, and complications. Twelve patients who presented between February 2009 and February 2011 with spontaneous rib fracture were reviewed retrospectively. The patients' data were evaluated according to anamnesis, physical examination, and chest radiographs. The ages of the patients ranged from 34 to 77 years (mean 55.91 ± 12.20 years), and 7 (58.4%) were male. All patients had severe cough and chest pain. The fractures were most frequently between 4th and 9th ribs; multiple rib fractures were detected in 5 (41.7%) patients. Eight (66.7%) patients had chronic obstructive pulmonary disease, 2 (16.7%) had bronchial asthma, and 2 (16.7%) had osteoporosis. Bone densitometry revealed a high risk of bone fracture in all patients. Patients with chronic obstructive pulmonary disease or bronchial asthma had been treated with high-dose steroids for over a year. Spontaneous rib fracture due to severe cough may occur in patients with osteoporosis, chronic obstructive pulmonary disease, or bronchial asthma, receiving long-term steroid therapy. If these patients have severe chest pain, chest radiography should be performed to check for bone lesions. © The Author(s) 2015.

  20. Spontaneous transverse colon volvulus

    PubMed Central

    Sana, Landolsi; Ali, Gassara; Kallel, Helmi; Amine, Baklouti; Ahmed, Saadaoui; Mohamed Ali, Elouer; Wajdi, Chaeib; Saber, Mannaï

    2013-01-01

    We report a case of spontaneous transverse colon volvulus in a young healthy woman. It constitutes an unusual case since it occurred in a young healthy woman with a subacute onset and no aetiological factor has been found. Its diagnosis is still challenging. Prompt recognition with emergency intervention constitutes the key to successful outcome. PMID:23785565

  1. Spontaneous transverse colon volvulus.

    PubMed

    Sana, Landolsi; Ali, Gassara; Kallel, Helmi; Amine, Baklouti; Ahmed, Saadaoui; Ali, Elouer Mohamed; Wajdi, Chaeib; Saber, Mannaï

    2013-01-01

    We report a case of spontaneous transverse colon volvulus in a young healthy woman. It constitutes an unusual case since it occurred in a young healthy woman with a subacute onset and no aetiological factor has been found. Its diagnosis is still challenging. Prompt recognition with emergency intervention constitutes the key to successful outcome.

  2. Spontaneous fulminant gas gangrene.

    PubMed

    Delbridge, M S; Turton, E P L; Kester, R C

    2005-07-01

    Gas gangrene is a rare condition, usually associated with contaminated traumatic injuries. It carries a high rate of mortality and morbidity. A number of studies have implicated non-traumatic gas gangrene and colonic neoplasia. This paper reports a patient who presented spontaneously with Clostridium septicum gas gangrene and an occult caecal carcinoma.

  3. [Spontaneous bacterial peritonitis].

    PubMed

    Velkey, Bálint; Vitális, Eszter; Vitális, Zsuzsanna

    2017-01-01

    Spontaneous bacterial peritonitis occurs most commonly in cirrhotic patients with ascites. Pathogens get into the circulation by intestinal translocation and colonize in peritoneal fluid. Diagnosis of spontaneous bacterial peritonitis is based on elevated polymorphonuclear leukocyte count in the ascites (>0,25 G/L). Ascites culture is often negative but aids to get information about antibiotic sensitivity in positive cases. Treatment in stable patient can be intravenous then orally administrated ciprofloxacin or amoxicillin/clavulanic acid, while in severe cases intravenous III. generation cephalosporin. Nosocomial spontaneous bacterial peritonitis often caused by Gram-positive bacteria and multi-resistant pathogens can also be expected thus carbapenem should be the choice of the empiric treatment. Antibiotic prophylaxis should be considered. Norfloxacin is used most commonly, but changes are expected due to increase in quinolone resistance. As a primary prophylaxis, a short-term antibiotic treatment is recommended after gastrointestinal bleeding for 5 days, while long-term prophylaxis is for patients with low ascites protein, and advanced disease (400 mg/day). Secondary prophylaxis is recommended for all patients recovered from spontaneous bacterial peritonitis. Due to increasing antibiotic use of antibiotics prophylaxis is debated to some degree. Orv. Hetil., 2017, 158(2), 50-57.

  4. Spontaneous intracranial hypotension.

    PubMed Central

    Renowden, S A; Gregory, R; Hyman, N; Hilton-Jones, D

    1995-01-01

    The clinical features and radiological appearances of spontaneous intracranial hypotension are described in three patients and the medical literature is reviewed. Awareness of this condition and its differentiation from more sinister meningitic processes is important to avoid unnecessary invasive investigations and to allow prompt diagnosis and effective treatment. Images PMID:8530936

  5. Homogeneous catalyst formulations for methanol production

    DOEpatents

    Mahajan, Devinder; Sapienza, Richard S.; Slegeir, William A.; O'Hare, Thomas E.

    1991-02-12

    There is disclosed synthesis of CH.sub.3 OH from carbon monoxide and hydrogen using an extremely active homogeneous catalyst for methanol synthesis directly from synthesis gas. The catalyst operates preferably between 100.degree.-150.degree. C. and preferably at 100-150 psia synthesis gas to produce methanol. Use can be made of syngas mixtures which contain considerable quantities of other gases, such as nitrogen, methane or excess hydrogen. The catalyst is composed of two components: (a) a transition metal carbonyl complex and (b) an alkoxide component. In the simplest formulation, component (a) is a complex of nickel tetracarbonyl and component (b) is methoxide (CH.sub.3 O.sup.-), both being dissolved in a methanol solvent system. The presence of a co-solvent such as p-dioxane, THF, polyalcohols, ethers, hydrocarbons, and crown ethers accelerates the methanol synthesis reaction.

  6. Homogeneous catalyst formulations for methanol production

    DOEpatents

    Mahajan, Devinder; Sapienza, Richard S.; Slegeir, William A.; O'Hare, Thomas E.

    1990-01-01

    There is disclosed synthesis of CH.sub.3 OH from carbon monoxide and hydrogen using an extremely active homogeneous catalyst for methanol synthesis directly from synthesis gas. The catalyst operates preferably between 100.degree.-150.degree. C. and preferably at 100-150 psia synthesis gas to produce methanol. Use can be made of syngas mixtures which contain considerable quantities of other gases, such as nitrogen, methane or excess hydrogen. The catalyst is composed of two components: (a) a transition metal carbonyl complex and (b) an alkoxide component. In the simplest formulation, component (a) is a complex of nickel tetracarbonyl and component (b) is methoxide (CH.sub.3 O.sup.13 ), both being dissolved in a methanol solvent system. The presence of a co-solvent such as p-dioxane, THF, polyalcohols, ethers, hydrocarbons, and crown ethers accelerates the methanol synthesis reaction.

  7. Methanol: A Versatile Fuel for Immediate Use

    ERIC Educational Resources Information Center

    Reed, T. B.; Lerner, R. M.

    1973-01-01

    Advocates the large-scale production and use of methanol as a substitute for the diminishing reserves of low-cost petroleum resources. Describes the manufacturing process and advantages of the versatile fuel. (JR)

  8. Methanol production from fermentor off-gases

    NASA Astrophysics Data System (ADS)

    Dale, B. E.; Moreira, A. R.

    The off gases from an acetone butanol fermentation facility are composed mainly of CO2 and H2. Such a gas stream is an ideal candidate as a feed to a methanol synthesis plant utilizing modern technology recently developed and known as the CDH-methanol process. A detailed economic analysis for the incremental cost of a methanol synthesis plant utilizing the off gases from an acetone butanol fermentation indicates a profitable rate of return of 25 to 30% under the most likely production conditions. Bench scale studies at different fermentor mixing rates indicate that the volume of gases released during the fermentation is a strong function of the agitation rate and point to a potential interaction between the volume of H2 evolved and the levels of butanol present in the final fermented broth. Such interaction may require establishing optimum operating conditions for an integrated butanol fermentation methanol synthesis plant.

  9. BHP may scale up methanol production

    SciTech Connect

    Alperowicz, N.

    1993-06-23

    Broken Hill Pty. (BHP: Melbourne) says otherwise uneconomic gas reserves in the Timor Sea off northwest Australia could be developed if the company`s plans to commercialize a novel gas-to-methanol technology prove to be viable. BHP is building an A$70-million ($50 million) research unit in Victoria using ICI`s Leading Concept Methanol gas-to-methanol process. If this unit proves viable, it could be put on a vessel and taken to Timor Sea where BHP has oil exploration and production interests. Timor gas is not economically viable because of lack of nearby markets. The 54,000-m.t./year research plant, located at Werrbee near Melbourne, is scheduled to start production in the second half of 1994, according to BHP manager Joe Evon. The plant is being built by Davy/John Brown. Provided the economic climate is right, BHP is expected to build a world-scale methanol plant offshore.

  10. Advances in direct oxidation methanol fuel cells

    NASA Technical Reports Server (NTRS)

    Surampudi, S.; Narayanan, S. R.; Vamos, E.; Frank, H.; Halpert, G.; Laconti, Anthony B.; Kosek, J.; Prakash, G. K. Surya; Olah, G. A.

    1993-01-01

    Fuel cells that can operate directly on fuels such as methanol are attractive for low to medium power applications in view of their low weight and volume relative to other power sources. A liquid feed direct methanol fuel cell has been developed based on a proton exchange membrane electrolyte and Pt/Ru and Pt catalyzed fuel and air/O2 electrodes, respectively. The cell has been shown to deliver significant power outputs at temperatures of 60 to 90 C. The cell voltage is near 0.5 V at 300 mA/cm(exp 2) current density and an operating temperature of 90 C. A deterrent to performance appears to be methanol crossover through the membrane to the oxygen electrode. Further improvements in performance appear possible by minimizing the methanol crossover rate.

  11. Methanol: A Versatile Fuel for Immediate Use

    ERIC Educational Resources Information Center

    Reed, T. B.; Lerner, R. M.

    1973-01-01

    Advocates the large-scale production and use of methanol as a substitute for the diminishing reserves of low-cost petroleum resources. Describes the manufacturing process and advantages of the versatile fuel. (JR)

  12. Methanol in the sky with diamonds

    NASA Technical Reports Server (NTRS)

    Allamandola, L. J.; Sandford, S. A.; Tielens, A. G. G. M.; Herbst, T.

    1991-01-01

    The present of gas phase methanol in dense interstellar molecular clouds was established by radio detection of its rotational emission lines. However, the position, width, and profile of a absorption band near 1470 cm(exp -1) in the IR spectra of many dense molecular clouds strongly suggests that solid methanol is an important component of interstellar ices. In an attempt to better constrain the identification of 1470 cm(exp -1) feature, we began a program to search for other characteristic absorption bands of solid state methanol in the spectra of objects known to produce this band. One such feature is now identified in the spectra of several dense molecular clouds and its position, width, and profile fit well with those of laboratory H2O:CH3OH ices. Thus, the presence of methanol-bearing ices in space is confirmed.

  13. Urine methanol concentration and alcohol hangover severity.

    PubMed

    Mackus, M; Van de Loo, A J A E; Korte-Bouws, G A H; Van Neer, R H P; Wang, X; Nguyen, T T; Brookhuis, K A; Garssen, J; Verster, J C

    2017-03-01

    Congeners are substances, other than ethanol, that are produced during fermentation. Previous research found that the consumption of congener-rich drinks contributes to the severity of alcohol hangover. Methanol is such a congener that has been related to alcohol hangover. Therefore, the aim of this study was to examine the relationship between urine methanol concentration and alcohol hangover severity. N = 36 healthy social drinkers (22 females, 14 males), aged 18-30 years old, participated in a naturalistic study, comprising a hangover day and a control day (no alcohol consumed the previous day). N = 18 of them had regular hangovers (the hangover group), while the other N = 18 claimed to be hangover-immune (hangover-immune group). Overall hangover severity was assessed, and that of 23 individual hangover symptoms. Urine methanol concentrations on the hangover and control days were compared, and correlated to hangover (symptom) severity. Urine methanol concentration was significantly higher on hangover days compared to control days (p = 0.0001). No significant differences in urine methanol concentration were found between the hangover group and hangover-immune group. However, urine methanol concentration did not significantly correlate with overall hangover severity (r = -0.011, p = 0.948), nor with any of the individual hangover symptoms. These findings were observed also when analyzing the data separately for the hangover-immune group. In the hangover group, a significant correlation with urine methanol concentration was found only with vomiting (r = 0.489, p = 0.037). No significant correlation was observed between urine methanol concentration and hangover severity, nor with individual core hangover symptoms. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Assessment of the cancer potential of methanol.

    PubMed

    Cruzan, George

    2009-01-01

    There are no published cancer studies of methanol-exposed cohorts. Genotoxicity studies do not suggest carcinogenic activity from methanol exposure. Oncogenicity studies of methanol were conducted by inhalation for approximately 20 hrs/day at up to 1000 ppm in F344 rats and B6C3F1 mice (NEDO), and by incorporation into drinking water at up to 20,000 ppm in Sprague-Dawley rats (Ramazzini Foundation, by Soffritti et al.). No increased neoplasms were found in the NEDO rat and mouse inhalation studies, even at air levels (up to 1000 ppm for >19 hours/day, 7 days/week) that caused 10-fold increased blood methanol levels. The maximum dose level was 600 mg/kg/day. The breakdown of methanol to formaldehyde in rats is saturated at doses above 600 mg/kg according to Horton et al. Thus, higher inhalation exposure concentrations are not expected to lead to tumors in rats or mice. In the Soffritti et al. study there was excessive early mortality, and lung pathology (inflammation, dysplasia, or neoplasm) was present in 87-94% of those dying anytime in the study. Soffritti et al. reported lympho-immunoblastic lymphoma. There are no historical control data to which this study can be compared because this diagnosis is not used by any other pathologist in animal studies. Lung infections probably played a role in formation of the lesions called lympho-immunoblastic lymphoma in the Ramazzini methanol study. The data from genotoxicity studies, the inhalation and drinking water oncogenicity studies of methanol in rats and mice, and mode of action considerations support a conclusion that methanol is not likely to be carcinogenic in humans.

  15. Transesterification of waste vegetable oil under pulse sonication using ethanol, methanol and ethanol–methanol mixtures

    SciTech Connect

    Martinez-Guerra, Edith; Gude, Veera Gnaneswar

    2014-12-15

    Highlights: • Pulse sonication effect on transesterification of waste vegetable oil was studied. • Effects of ethanol, methanol, and alcohol mixtures on FAMEs yield were evaluated. • Effect of ultrasonic intensity, power density, and its output rates were evaluated. • Alcohol mixtures resulted in higher biodiesel yields due to better solubility. - Abstract: This study reports on the effects of direct pulse sonication and the type of alcohol (methanol and ethanol) on the transesterification reaction of waste vegetable oil without any external heating or mechanical mixing. Biodiesel yields and optimum process conditions for the transesterification reaction involving ethanol, methanol, and ethanol–methanol mixtures were evaluated. The effects of ultrasonic power densities (by varying sample volumes), power output rates (in W), and ultrasonic intensities (by varying the reactor size) were studied for transesterification reaction with ethanol, methanol and ethanol–methanol (50%-50%) mixtures. The optimum process conditions for ethanol or methanol based transesterification reaction of waste vegetable oil were determined as: 9:1 alcohol to oil ratio, 1% wt. catalyst amount, 1–2 min reaction time at a power output rate between 75 and 150 W. It was shown that the transesterification reactions using ethanol–methanol mixtures resulted in biodiesel yields as high as >99% at lower power density and ultrasound intensity when compared to ethanol or methanol based transesterification reactions.

  16. Methanol-Tolerant Cathode Catalyst Composite For Direct Methanol Fuel Cells

    DOEpatents

    Zhu, Yimin; Zelenay, Piotr

    2006-03-21

    A direct methanol fuel cell (DMFC) having a methanol fuel supply, oxidant supply, and its membrane electrode assembly (MEA) formed of an anode electrode and a cathode electrode with a membrane therebetween, a methanol oxidation catalyst adjacent the anode electrode and the membrane, an oxidant reduction catalyst adjacent the cathode electrode and the membrane, comprises an oxidant reduction catalyst layer of a platinum-chromium alloy so that oxidation at the cathode of methanol that crosses from the anode through the membrane to the cathode is reduced with a concomitant increase of net electrical potential at the cathode electrode.

  17. Methanol-tolerant cathode catalyst composite for direct methanol fuel cells

    DOEpatents

    Zhu, Yimin; Zelenay, Piotr

    2006-09-05

    A direct methanol fuel cell (DMFC) having a methanol fuel supply, oxidant supply, and its membrane electrode assembly (MEA) formed of an anode electrode and a cathode electrode with a membrane therebetween, a methanol oxidation catalyst adjacent the anode electrode and the membrane, an oxidant reduction catalyst adjacent the cathode electrode and the membrane, comprises an oxidant reduction catalyst layer of Pt.sub.3Cr/C so that oxidation at the cathode of methanol that crosses from the anode through the membrane to the cathode is reduced with a concomitant increase of net electrical potential at the cathode electrode.

  18. Vacuum-Ultraviolet (VUV) Photoionization of Small Methanol and Methanol-Water Clusters

    SciTech Connect

    Kostko, Oleg; Belau, Leonid; Wilson, Kevin R.; Ahmed, Musahid

    2008-04-24

    In this work, we report on the vacuum-ultraviolet (VUV) photoionization of small methanol and methanol-water clusters. Clusters of methanol with water are generated via co-expansion of the gas phase constituents in a continuous supersonic jet expansion of methanol and water seeded in Ar. The resulting clusters are investigated by single photon ionization with tunable vacuum-ultraviolet synchrotron radiation and mass analyzed using reflectron mass spectrometry. Protonated methanol clusters of the form (CH3OH)nH+(n = 1-12) dominate the mass spectrum below the ionization energy of the methanol monomer. With an increase in water concentration, small amounts of mixed clusters of the form (CH3OH n(H2O)H+ (n = 2-11) are detected. The only unprotonated species observed in this work are the methanol monomer and dimer. Appearance energies are obtained from the photoionization efficiency (PIE) curves for CH3OH+, (CH3OH)2+, (CH3OH)nH+ (n = 1-9), and (CH3OH)n(H2O)H+ (n = 2-9) as a function of photon energy. With an increasein the water content in the molecular beam, there is an enhancement of photoionization intensity for the methanol dimer and protonated methanol monomer at threshold. These results are compared and contrasted to previous experimental observations.

  19. Vacuum-ultraviolet (VUV) photoionization of small methanol and methanol-water clusters

    SciTech Connect

    Ahmed, Musahid; Ahmed, Musahid; Wilson, Kevin R.; Belau, Leonid; Kostko, Oleg

    2008-05-12

    In this work we report on thevacuum-ultraviolet (VUV) photoionization of small methanol and methanol-water clusters. Clusters of methanol with water are generated via co-expansion of the gas phase constituents in a continuous supersonic jet expansion of methanol and water seeded in Ar. The resulting clusters are investigated by single photon ionization with tunable vacuumultraviolet synchrotron radiation and mass analyzed using reflectron mass spectrometry. Protonated methanol clusters of the form (CH3OH)nH + (n=1-12) dominate the mass spectrum below the ionization energy of the methanol monomer. With an increase in water concentration, small amounts of mixed clusters of the form (CH3OH)n(H2O)H + (n=2-11) are detected. The only unprotonated species observed in this work are the methanol monomer and dimer. Appearance energies are obtained from the photoionization efficiency (PIE) curves for CH3OH +, (CH 3OH)2 +, (CH3OH)nH + (n=1-9), and (CH 3OH)n(H2O)H + (n=2-9 ) as a function of photon energy. With an increase in the water content in the molecular beam, there is an enhancement of photoionization intensity for methanol dimer and protonated methanol monomer at threshold. These results are compared and contrasted to previous experimental observations.

  20. Integrated anode structure for passive direct methanol fuel cells with neat methanol operation

    NASA Astrophysics Data System (ADS)

    Wu, Huijuan; Zhang, Haifeng; Chen, Peng; Guo, Jing; Yuan, Ting; Zheng, Junwei; Yang, Hui

    2014-02-01

    A microporous titanium plate based integrated anode structure (Ti-IAS) suitable for passive direct methanol fuel cells (DMFCs) fueled with neat methanol is reported. This anode structure incorporates a porous titanium plate as a methanol mass transfer barrier and current collector, pervaporation film for passively vaporizing methanol, vaporous methanol cavity for evenly distributing fuel, and channels for carbon dioxide venting. With the effective control of methanol delivery rate, the Ti-IAS based DMFC allows the direct use of neat methanol as the fuel source. In the meantime, the required water for methanol-oxidation reaction at the anode can also be fully recovered from the cathode with the help of the highly hydrophobic microporous layer in the cathode. DMFCs incorporating this new anode structure exhibit a power density as high as 40 mW cm-2 and a high volumetric energy density of 489 Wh L-1 operating with neat methanol and at 25 °C. Importantly, no obvious performance degradation of the passive DMFC system is observed after more than 90 h of continuous operation. The experimental results reveal that the compact DMFC based on the Ti-IAS exhibits a substantial potential as power sources for portable applications.

  1. Microfluidic distillation chip for methanol concentration detection.

    PubMed

    Wang, Yao-Nan; Liu, Chan-Chiung; Yang, Ruey-Jen; Ju, Wei-Jhong; Fu, Lung-Ming

    2016-03-17

    An integrated microfluidic distillation system is proposed for separating a mixed ethanol-methanol-water solution into its constituent components. The microfluidic chip is fabricated using a CO2 laser system and comprises a serpentine channel, a boiling zone, a heating zone, and a cooled collection chamber filled with de-ionized (DI) water. In the proposed device, the ethanol-methanol-water solution is injected into the microfluidic chip and driven through the serpentine channel and into the collection chamber by means of a nitrogen carrier gas. Following the distillation process, the ethanol-methanol vapor flows into the collection chamber and condenses into the DI water. The resulting solution is removed from the collection tank and reacted with a mixed indicator. Finally, the methanol concentration is inversely derived from the absorbance measurements obtained using a spectrophotometer. The experimental results show the proposed microfluidic system achieves an average methanol distillation efficiency of 97%. The practicality of the proposed device is demonstrated by detecting the methanol concentrations of two commercial fruit wines. It is shown that the measured concentration values deviate by no more than 3% from those obtained using a conventional bench top system.

  2. Methanol conversion to light olefins over SAPO-34. Sorption, diffusion, and catalytic reactions

    SciTech Connect

    Chen, D.; Rebo, H.P.; Moljord, K.; Holmen, A.

    1999-11-01

    The catalytic conversion of methanol to lower olefins (MTO) is a way of converting natural gas and coal to chemicals via methanol. The effects of adsorption and diffusion of the reactants on methanol to olefins (MTO) and propene conversion over SAPO-34 have been studied in an oscillating microbalance reactor. The adsorption parameters of methanol and propene at reaction conditions (698 K) were determined by a pulse method, and the results were identical to the values obtained by extrapolation from low temperatures (323--398 K). Inverse uptake diffusion times were calculated form adsorption data at low temperatures, and these results were dependent on the temperature and the adsorbed amount. The inverse steady-state diffusion times calculated form the inverse uptake diffusion times were independent of the temperature and the adsorbed amount. The influence of diffusion on the reaction rates was estimated on the basis of the inverse steady-state diffusion times, using the Weisz-Prater criterion. The methanol conversion over SAPO-34 was influenced by diffusion of the reactant, while the propene conversion was not. A kinetic study revealed that both the rate constant and the site coverage of propene were much lower than that of methanol at 698 K. The deactivation behavior during the MTO reaction over SAPO-34 was studied by measuring both the adsorbed amount of methanol and the conversion at different coke contents. Catalyst deactivation was proposed to be due to a decreasing number of sites available for adsorption at high coke contents and a lower diffusivity, hence a lower effectiveness factor due to coke deposition.

  3. Solution-based deposition of ultrathin metal oxide films on metal and superconductor surfaces

    NASA Astrophysics Data System (ADS)

    Westwood, Glenn

    Solution chemical methods were used to deposit ultrathin metal oxide films on metal and superconductor surfaces. Platinum-molybdenum oxide films were deposited by spontaneous adsorption and electrodeposition of hexamolybdoplatinate, PtMO6O248-. Spectroscopic characterization by 17O and 195Pt NMR showed that the PtMo6O248- anion is stable in aqueous solution below pH 4. The interaction of this solution stable anion with Au and Ag was characterized by in situ scanning tunneling microscopy, x-ray photoelectron spectroscopy, and cyclic voltammetry. The anion was partially reduced upon adsorption on Ag, but spontaneously adsorbed on Au to form an amorphous surface phase. The electrodeposition of hexamolybdoplatinate on Au electrodes resulted in an electrode surface that was different from the spontaneously adsorbed species, in terms of composition, voltammetry, and reactivity. Cyclic voltammetry was also used to compare the reactivity of these materials for the electrooxidation of methanol. Ultrathin zirconia films were deposited on YBa2Cu3O 7-delta by alternating exposures to tetra n-propyl zirconate, Zr4(OPrn)16, and H2O in n-propanol. Physical and chemical characterization of these films was done by x-ray photoelectron spectroscopy, atomic force microscopy, and cross-section transmission electron microscopy. The zirconia films were determined to be ultrathin (<10 nm) and highly conformal to the surface of YBa2Cu3O7-delta. Metal-insulator-superconductor tunnel junctions fabricated in this fashion were characterized by current-voltage and conductivity-voltage measurements. Solution deposition from Zr4(OPrn) 16 was also used to deposit ultrathin zirconia films on gold, silver, and aluminum surfaces. X-ray photoelectron spectroscopy and atomic force microscopy were used to compare the physical properties of these films. Electrical measurements showed that zirconia films on Ag and Au are not insulating, but aluminum-zirconia-aluminum capacitors fabricated by this method

  4. Spontaneous healing of spontaneous coronary artery dissection.

    PubMed

    Almafragi, Amar; Convens, Carl; Heuvel, Paul Van Den

    2010-01-01

    Spontaneous coronary artery dissection (SCAD) is a rare cause of acute coronary syndrome and sudden cardiac death. It should be suspected in every healthy young woman without cardiac risk factors, especially during the peripartum or postpartum periods. It is important to check for a history of drug abuse, collagen vascular disease or blunt trauma of the chest. Coronary angiography is essential for diagnosis and early management. We wonder whether thrombolysis might aggravate coronary dissection. All types of treatment (medical therapy, percutaneous intervention or surgery) improve the prognosis without affecting survival times if used appropriately according to the clinical stability and the angiographic features of the involved coronary arteries. Prompt recognition and targeted treatment improve outcomes. We report a case of SCAD in a young female free of traditional cardiovascular risk factors, who presented six hours after thrombolysis for ST elevation myocardial infarction. Coronary angiography showed a dissection of the left anterior descending and immediate branch. She had successful coronary artery bypass grafting, with complete healing of left anterior descending dissection.

  5. Coke formation and carbon atom economy of methanol-to-olefins reaction.

    PubMed

    Wei, Yingxu; Yuan, Cuiyu; Li, Jinzhe; Xu, Shutao; Zhou, You; Chen, Jingrun; Wang, Quanyi; Xu, Lei; Qi, Yue; Zhang, Qing; Liu, Zhongmin

    2012-05-01

    The methanol-to-olefins (MTO) process is becoming the most important non-petrochemical route for the production of light olefins from coal or natural gas. Maximizing the generation of the target products, ethene and propene, and minimizing the production of byproducts and coke, are major considerations in the efficient utilization of the carbon resource of methanol. In the present work, the heterogeneous catalytic conversion of methanol was evaluated by performing simultaneous measurements of the volatile products generated in the gas phase and the confined coke deposition in the catalyst phase. Real-time and complete reaction profiles were plotted to allow the comparison of carbon atom economy of methanol conversion over the catalyst SAPO-34 at varied reaction temperatures. The difference in carbon atom economy was closely related with the coke formation in the SAPO-34 catalyst. The confined coke compounds were determined. A new type of confined organics was found, and these accounted for the quick deactivation and low carbon atom economy under low-reaction-temperature conditions. Based on the carbon atom economy evaluation and coke species determination, optimized operating conditions for the MTO process are suggested; these conditions guarantee high conversion efficiency of methanol.

  6. Delayed neurological sequelae from ethylene glycol, diethylene glycol and methanol poisonings.

    PubMed

    Reddy, Nandi J; Sudini, Madhuri; Lewis, Lionel D

    2010-12-01

    Ethylene glycol, diethylene glycol and methanol are widely available chemicals and are found in a variety of common household products including antifreeze, windshield washer fluid, brake fluid and lubricants. Following ingestion of these glycols and methanol, patients frequently develop an early neurological syndrome consisting of inebriation, ataxia, and if severe, seizures and coma. Though uncommon, a neurological syndrome may also develop as a delayed complication. Using Pub Med 438 references were identified of which 45 were relevant. Ethylene glycol poisoning has produced cranial nerve deficits (usually VII nerve dysfunction) after a delay of 5-20 days, Parkinsonism and cerebral edema. Diethylene glycol ingestion has been associated with the development of optic nerve injury, cranial nerve deficits, quadraparesis and peripheral neuropathy. Methanol poisoning has led to Parkinsonism and polyneuropathy. Oxalate crystal deposition likely causes the cranial neuropathies related to ethylene glycol and 2-hydroxyethoxyacetic acid is thought to be the causal moiety in cranial neuropathies resulting from diethylene glycol toxicity. Formic acid is implicated in the optic nerve damage associated with methanol. Uncommonly, delayed neurological syndromes may develop as complications of poisoning due to ethylene glycol, diethylene glycol and methanol; the onset of such neurological damage is often days or even weeks post-ingestion. Further research is required to explain why the facial nerve is the cranial nerve most commonly involved and why the basal ganglia are predisposed to injury.

  7. Application of green chemistry techniques to prepare electrocatalysts for direct methanol fuel cells.

    PubMed

    Shimizu, Kenichi; Wang, Joanna S; Wai, Chien M

    2010-03-25

    A series of green techniques for synthesizing carbon nanotube-supported platinum nanoparticles and their high electrocatalytic activity toward methanol fuel cell applications are reported. The techniques utilize either the supercritical fluid carbon dioxide or water as a medium for depositing platinum nanoparticles on surfaces of multiwalled or single-walled carbon nanotubes. The catalytic properties of the carbon nanotubes-supported Pt nanoparticle catalysts prepared by four different techniques are compared for anodic oxidation of methanol and cathodic reduction of oxygen using cyclic voltammetry. One technique using galvanic exchange of Pt(2+) in water with zerovalent iron present on the surfaces of as-grown single-walled carbon nanotubes produces a Pt catalyst that shows an unusually high catalytic activity for reduction of oxygen but a negligible activity for oxidation of methanol. This fuel-selective catalyst may have a unique application as a cathode catalyst in methanol fuel cells to alleviate the problems caused by crossover of methanol through the polymer electrolyte membrane.

  8. Spontaneous ileostomy closure

    PubMed Central

    Alyami, Mohammad S.; Lundberg, Peter W.; Cotte, Eddy G.; Glehen, Olivier J.

    2016-01-01

    Iatrogenic ileostomies are routinely placed during colorectal surgery for the diversion of intestinal contents to permit healing of the distal anastomosis prior to elective reversal. We present an interesting case of spontaneous closure of a diverting ileostomy without any adverse effects to the patient. A 65-year-old woman, positive for hereditary non-polyposis colorectal cancer type-I, with locally invasive cancer of the distal colon underwent en-bloc total colectomy, hysterectomy, and bilateral salpingoophorectomy with creation of a proximal loop ileostomy. The ostomy temporarily closed without reoperation at 10 weeks, after spontaneously reopening, it definitively closed, again without surgical intervention at 18 weeks following the original surgery. This rare phenomenon has occurred following variable colorectal pathology and is poorly understood, particularly in patients with aggressive disease and adjunct perioperative interventions. PMID:27279518

  9. Arachnoid cyst spontaneous rupture.

    PubMed

    Marques, Inês Brás; Vieira Barbosa, José

    2014-01-01

    Arachnoid cysts are benign congenital cerebrospinal fluid collections, usually asymptomatic and diagnosed incidentally in children or adolescents. They may become symptomatic after enlargement or complications, frequently presenting with symptoms of intracranial hypertension. We report an unusual case of progressive refractory headache in an adult patient due to an arachnoid cyst spontaneous rupture. Although clinical improvement occurred with conservative treatment, the subdural hygroma progressively enlarged and surgical treatment was ultimately needed. Spontaneous rupture is a very rare complication of arachnoid cysts. Accumulation of cerebrospinal fluid accumulation in the subdural space causes sustained intracranial hypertension that may be life-threatening and frequently requires surgical treatment. Patients with arachnoid cysts must be informed on their small vulnerability to cyst rupture and be aware that a sudden and severe headache, especially if starting after minor trauma or a Valsalva manoeuvre, always requires medical evaluation.

  10. Spontaneous Perforation of Pyometra

    PubMed Central

    Singh, Ahanthem Santa; Bhaphiralyne, Wankhar

    2016-01-01

    Pyometra is collection of purulent material which occurs when there is interference with its normal drainage. It is an uncommon condition with incidence of 0.1 to 0.5% of all gynecological patients. Spontaneous rupture of uterus is an extremely rare complication of pyometra. A 65-year-old lady presented with pain abdomen and purulent vaginal discharge. Preoperative diagnosis of pyometra was made by magnetic resonance imaging (MRI). Laparotomy followed by peritoneal lavage and repair of perforation was performed. Although spontaneously perforated pyometra is rare, the condition must be borne in mind with regard to elderly women with acute abdominal pain. Preoperative diagnosis of perforated pyometra is absolutely essential. Computed tomography (CT) and MRI are diagnostic tools. In selected cases conservative approach at surgery can be opted. PMID:27152313

  11. Spontaneous Perforation of Pyometra.

    PubMed

    Sharma, Nalini; Singh, Ahanthem Santa; Bhaphiralyne, Wankhar

    2016-04-01

    Pyometra is collection of purulent material which occurs when there is interference with its normal drainage. It is an uncommon condition with incidence of 0.1 to 0.5% of all gynecological patients. Spontaneous rupture of uterus is an extremely rare complication of pyometra. A 65-year-old lady presented with pain abdomen and purulent vaginal discharge. Preoperative diagnosis of pyometra was made by magnetic resonance imaging (MRI). Laparotomy followed by peritoneal lavage and repair of perforation was performed. Although spontaneously perforated pyometra is rare, the condition must be borne in mind with regard to elderly women with acute abdominal pain. Preoperative diagnosis of perforated pyometra is absolutely essential. Computed tomography (CT) and MRI are diagnostic tools. In selected cases conservative approach at surgery can be opted.

  12. Spontaneous Rupture of Pyometra

    PubMed Central

    Mallah, Fatemeh; Eftekhar, Tahere; Naghavi-Behzad, Mohammad

    2013-01-01

    Spontaneous perforation is a very rare complication of pyometra. The clinical findings of perforated pyometra are similar to perforation of the gastrointestinal tract and other causes of acute abdomen. In most cases, a correct and definite diagnosis can be made only by laparotomy. We report two cases of diffuse peritonitis caused by spontaneous perforated pyometra. The first case is a 78-year-old woman with abdominal pain for which laparotomy was performed because of suspected incarcerated hernia. The second case is a 61-year-old woman with abdominal pain for which laparotomy was performed because of symptoms of peritonitis. At laparotomy of both cases, 1 liter of pus with the source of uterine was found in the abdominal cavity. The ruptured uterine is also detected. More investigations revealed no malignancy as the reason of the pyometra. PMID:24024054

  13. [Spontaneous pneumothorax in children].

    PubMed

    Michel, J L

    2000-03-01

    Spontaneous pneumothorax is rare in childhood. Before 12 years of age the main underlying pathologies are asthma, cystic malformations, post infectious bullae, and infectious pneumoniae. After 12 years of age it is mainly associated with cystic fibrosis and constitutional slim morphology. Symptoms vary according to the extent of lung collapse and the diagnosis is confirmed on chest X rays. In mildly symptomatic pneumothorax, spontaneous resolution is achieved within few days. When cardiorespiratory difficulties are present, mechanical evacuation of air from the pleural cavity is necessary through a tube drainage maintained until complete pulmonary reexpansion. Surgical treatment is indicated in case of persisting air leakage after one week of efficient drainage, large cystic malformation or post infectious bullae, recurring or bilateral pneumothorax.

  14. [Spontaneous spinal cord herniation].

    PubMed

    Rivas, J J; de la Lama, A; Gonza Lez, P; Ramos, A; Zurdo, M; Alday, R

    2004-10-01

    Spontaneous spinal cord herniation through a dural defect is an unusual condition. This entity has been probably underestimated before the introduction of MRI. We report a case of a 49-year-old man with a progressive Brown-Sequard syndrome. MRI and CT myelogram showed a ventrally displaced spinal cord at level T6-T7 and expansion of the posterior subarachnoid space. Through a laminectomy, a spinal cord herniation was identified and reduced. The anterior dural defect was repaired with a patch of lyophilized dura. The patient recovered muscle power but there was no improvement of the sensory disturbance. The diagnosis of spontaneous spinal cord herniation must be considered when progressive myelopathy occurs in middle-aged patients, without signs of spinal cord compression and typical radiological findings. Surgical treatment may halt the progressive deficits and even yield improvement in many cases.

  15. Spontaneous Iliopsoas Tendon Tear

    PubMed Central

    Rodriguez, Mary; Patnaik, Soumya; Wang, Peter

    2016-01-01

    Hip pain is one of the most common reasons for the elderly to present to the emergency department, and the differential diagnosis spectrum is vast. Iliopsoas injury is a relatively uncommon condition that may present with hip or groin pain. It is usually seen in athletes due to trauma, particularly flexion injuries. However, spontaneous iliopsoas tendon tear is extremely rare, and only a small number of cases have been reported; it has an estimated prevalence of 0.66% in individuals from 7 to 95 years. Risk factors include aging, use of steroids, and chronic diseases. Magnetic resonance imaging (MRI) using its high soft-tissue contrast resolution remains the most valuable imaging modality. A prompt diagnosis and treatment, which is usually conservative, is important to improve the quality of life in this group of patients. We describe a case of spontaneous iliopsoas tendon tear in an elderly woman. PMID:26929854

  16. Spontaneous Transomental Hernia

    PubMed Central

    Lee, Seung Hun

    2016-01-01

    A transomental hernia through the greater or lesser omentum is rare, accounting for approximately 4% of internal hernias. Transomental hernias are generally reported in patients aged over fifty. In such instances, acquired transomental hernias are usual, are commonly iatrogenic, and result from surgical interventions or from trauma or peritoneal inflammation. In rare cases, such as the one described in this study, internal hernias through the greater or lesser omentum occur spontaneously as the result of senile atrophy without history of surgery, trauma, or inflammation. A transomental hernia has a high postoperative mortality rate of 30%, and emergency diagnosis and treatment are critical. We report a case of a spontaneous transomental hernia of the small intestine causing intestinal obstruction. An internal hernia with strangulation of the small bowel in the lesser sac was suspected from the image study. After an emergency laparotomy, a transomental hernia was diagnosed. PMID:26962535

  17. Spontaneous recovery from acalculia.

    PubMed

    Basso, Anna; Caporali, Alessandra; Faglioni, Pietro

    2005-01-01

    A topic much considered in research on acalculia was its relationship with aphasia. Far less attention has been given to the natural course of acalculia. In this retrospective study, we examined the relationship between aphasia and acalculia in an unselected series of 98 left-brain-damaged patients and the spontaneous recovery from acalculia in 92 acalculic patients with follow-up. There was a significant association between aphasia and acalculia although 19 participants exhibited aphasia with no acalculia and six acalculia with no aphasia. We observed significant improvement between a first examination carried out between 1 and 5 months post-onset and a second examination carried out between 3 and 11 months later (mean: 5 months). The mechanisms of spontaneous recovery are discussed.

  18. Spontaneous nephrocutaneous fistula.

    PubMed

    Antunes, Alberto A; Calado, Adriano A; Falcão, Evandro

    2004-01-01

    Spontaneous renal fistula to the skin is rare. The majority of cases develop in patients with antecedents of previous renal surgery, renal trauma, renal tumors, and chronic urinary tract infection with abscess formation. We report the case of a 62-year old woman, who complained of urine leakage through the skin in the lumbar region for 2 years. She underwent a fistulography that revealed drainage of contrast agent to the collecting system and images suggesting renal lithiasis on this side. The patient underwent simple nephrectomy on this side and evolved without intercurrences in the post-operative period. Currently, the occurrence of spontaneous renal and perirenal abscesses is extremely rare, except in patients with diabetes, neoplasias and immunodepression in general.

  19. Spontaneous Pneumomediastinum in Labor

    PubMed Central

    Benlamkadem, Said; Labib, Smael; Harandou, Mustapha

    2017-01-01

    Spontaneous pneumomediastinum and subcutaneous emphysema also known as Hamman's syndrome is a very rare complication of labor that is often related to the valsalva maneuver during the labor. In most case, Hamman's syndrome is a self-limiting condition, rarely complicated unless there are underlying respiratory diseases. Chest X-ray can be a useful early diagnostic technique in severe clinical presentation. We report an uneventful pregnancy in a primigravid parturient, which was complicated in the late second stage of labor by the development of subcutaneous emphysema, pneumomediastinum, and mild pneumothorax. Spontaneous recovery occurred after four days of conservative management. This condition shows the major interest of labor analgesia especially locoregional techniques. PMID:28316849

  20. Electrodeposition of PdCu alloy and its application in methanol electro-oxidation

    NASA Astrophysics Data System (ADS)

    Hsieh, Ming-Wei; Whang, Thou-Jen

    2013-04-01

    This study demonstrates a simple electrodeposition method to fabricate the palladium-copper alloy on an ITO coated glass (PdCu/ITO) and its application in methanol electro-oxidation. Our approaches involve the co-reduction of Pd and Cu using triethanolamine (TEA) as a complexing agent in the electroplating bath and a Pd redox replacement of Cu on the surface of the as-prepared PdCu alloy. The phase structures, alloy compositions and morphologies of catalysts are determined by X-ray diffraction, energy dispersive spectrometer and scanning electron microscopy, respectively. X-ray diffraction shows that the particle size of PdCu deposits shrink when the alloy is deposited in a TEA-contained solution. The electrocatalytic properties of PdCu alloys and Pd redox replacement modified PdCu alloys for methanol oxidation have been investigated by cyclic voltammetry. The PdCu alloy with atomic ratio of 20.5% Cu exhibits higher catalytic activity toward methanol oxidation compared with a pure Pd catalyst. PdCu alloys with smaller particle sizes associated with TEA agent and the surface confined Pd replacement are found to have enhanced catalytic performance in the electro-oxidation of methanol.

  1. Towards neat methanol operation of direct methanol fuel cells: a novel self-assembled proton exchange membrane.

    PubMed

    Li, Jing; Cai, Weiwei; Ma, Liying; Zhang, Yunfeng; Chen, Zhangxian; Cheng, Hansong

    2015-04-18

    We report here a novel proton exchange membrane with remarkably high methanol-permeation resistivity and excellent proton conductivity enabled by carefully designed self-assembled ionic conductive channels. A direct methanol fuel cell utilizing the membrane performs well with a 20 M methanol solution, very close to the concentration of neat methanol.

  2. Genetic and physical analyses of Methylobacterium organophilum XX genes encoding methanol oxidation

    SciTech Connect

    Machlin, S.M.; Tam, P.E.; Bastien, C.A.; Hanson, R.S.

    1988-01-01

    When allyl alcohol was used as a suicide substrate, spontaneous mutants and UV light- and nitrous acid-generated mutants of Methylobacterium organophilum XX were selected which grew on methylamine but not on methanol. There was no detectable methanol dehydrogenase (MDH) activity in crude extracts of these mutants, yet Western blots revealed that some mutants still produced MDH protein. Complementation of 50 mutants by a cosmid gene bank of M. organophilum XX demonstrated that three major regions of the genome, each of which was separated by a minimum of 40 kilobases, were required for expression of active MDH. By subcloning and Tn5 insertion mutagenesis of subcloned fragments, at least 11 genes clustered within these three regions were subsequently identified. The identity of the MDH structural gene, which was initially determined by hybridization to the structural gene of Methylobacterium sp. strain AM1, was confirmed by Western blot analysis of an MDH-..beta..-galactosidase fusion protein.

  3. Spontaneous spinal epidural abscess.

    PubMed

    Ellanti, P; Morris, S

    2011-10-01

    Spinal epidural abscess is an uncommon entity, the frequency of which is increasing. They occur spontaneously or as a complication of intervention. The classical triad of fever, back pain and neurological symptoms are not always present. High index of suspicion is key to diagnosis. Any delay in diagnosis and treatment can have significant neurological consequences. We present the case of a previously well man with a one month history of back pain resulting from an epidural abscess.

  4. Copper cluster size effect in methanol synthesis from CO2

    DOE PAGES

    Yang, Bing; Liu, Cong; Halder, Avik; ...

    2017-05-08

    Here, size-selected Cun catalysts (n = 3, 4, 20) were synthesized on Al2O3 thin films using mass-selected cluster deposition. A systematic study of size and support effects was carried out for CO2 hydrogenation at atmospheric pressure using a combination of in situ grazing incidence X-ray absorption spectroscopy, catalytic activity measurement, and first-principles calculations. The catalytic activity for methanol synthesis is found to strongly vary as a function of the cluster size; the Cu4/Al2O3 catalyst shows the highest turnover rate for CH3OH production. With only one atom less than Cu4, Cu3 showed less than 50% activity. Density functional theory calculations predictmore » that the activities of the gas-phase Cu clusters increase as the cluster size decreases; however, the stronger charge transfer interaction with Al2O3 support for Cu3 than for Cu4 leads to remarkably reduced binding strength between the adsorbed intermediates and supported Cu3, which subsequently results in a less favorable energetic pathway to transform carbon dioxide to methanol.« less

  5. Spontaneous Achilles tendon rupture in alkaptonuria

    PubMed Central

    Alajoulin, Omar A.; Alsbou, Mohammed S.; Ja’afreh, Somayya O.; Kalbouneh, Heba M.

    2015-01-01

    Alkaptonuria (AKU) is a rare inborn metabolic disease characterized by accumulation of homogentisic acid (HGA). Excretion of HGA in urine causes darkening of urine and its deposition in connective tissues causes dark pigmentation (ochronosis), early degeneration of articular cartilage, weakening of the tendons, and subsequent rupture. In this case report, we present a rare case of a patient presented with unilateral spontaneous rupture of Achilles tendon due to AKU. The patient developed most of the orthopedic manifestations of the disease earlier than typical presentations. Alkaptonuria patients should avoid strenuous exercises and foot straining especially in patients developing early orthopedic manifestations. PMID:26620992

  6. Assessment of methanol electro-oxidation for direct methanol-air fuel cells

    SciTech Connect

    Fritts, S.D.; Sen, R.K.

    1988-07-01

    The Office of Energy Storage and Distribution of the US Department of Energy (DOE) supports the development of a methanol-air fuel cell for transportation application. The approach used at Los Alamos National Laboratory converts the methanol fuel to a hydrogen-rich gas in a reformer, then operates the fuel cell on hydrogen and air. The reformer tends to be bulky (raising vehicle packaging problems), has a long startup period, and is not well suited for the transient operation required in a vehicle. Methanol, however, can be oxidized electrochemically in the fuel cell. If this process can be conducted efficiently, a direct methanol-air fuel cell can be used, which does not require a reformer. The objective of this study is to assess the potential of developing a suitable catalyst for the direct electrochemical oxidation of methanol. The primary conclusion of this study is that no acceptable catalysts exist can efficiently oxidize methanol electrochemically and have the desired cost and lifetime for vehicle applications. However, recent progress in understanding the mechanism of methanol oxidation indicates that a predictive base can be developed to search for methanol oxidation catalysts and can be used to methodically develop improved catalysts. Such an approach is strongly recommended. The study also recommends that until further progress in developing high-performance catalysts is achieved, research in cell design and testing is not warranted. 43 refs., 12 figs., 1 tab.

  7. A selective electrocatalyst–based direct methanol fuel cell operated at high concentrations of methanol

    PubMed Central

    Feng, Yan; Liu, Hui; Yang, Jun

    2017-01-01

    Owing to the serious crossover of methanol from the anode to the cathode through the polymer electrolyte membrane, direct methanol fuel cells (DMFCs) usually use dilute methanol solutions as fuel. However, the use of high-concentration methanol is highly demanded to improve the energy density of a DMFC system. Instead of the conventional strategies (for example, improving the fuel-feed system, membrane development, modification of electrode, and water management), we demonstrate the use of selective electrocatalysts to run a DMFC at high concentrations of methanol. In particular, at an operating temperature of 80°C, the as-fabricated DMFC with core-shell-shell Au@Ag2S@Pt nanocomposites at the anode and core-shell Au@Pd nanoparticles at the cathode produces a maximum power density of 89.7 mW cm−2 at a methanol feed concentration of 10 M and maintains good performance at a methanol concentration of up to 15 M. The high selectivity of the electrocatalysts achieved through structural construction accounts for the successful operation of the DMFC at high concentrations of methanol. PMID:28695199

  8. Transesterification of waste vegetable oil under pulse sonication using ethanol, methanol and ethanol-methanol mixtures.

    PubMed

    Martinez-Guerra, Edith; Gude, Veera Gnaneswar

    2014-12-01

    This study reports on the effects of direct pulse sonication and the type of alcohol (methanol and ethanol) on the transesterification reaction of waste vegetable oil without any external heating or mechanical mixing. Biodiesel yields and optimum process conditions for the transesterification reaction involving ethanol, methanol, and ethanol-methanol mixtures were evaluated. The effects of ultrasonic power densities (by varying sample volumes), power output rates (in W), and ultrasonic intensities (by varying the reactor size) were studied for transesterification reaction with ethanol, methanol and ethanol-methanol (50%-50%) mixtures. The optimum process conditions for ethanol or methanol based transesterification reaction of waste vegetable oil were determined as: 9:1 alcohol to oil ratio, 1% wt. catalyst amount, 1-2 min reaction time at a power output rate between 75 and 150 W. It was shown that the transesterification reactions using ethanol-methanol mixtures resulted in biodiesel yields as high as >99% at lower power density and ultrasound intensity when compared to ethanol or methanol based transesterification reactions.

  9. A selective electrocatalyst-based direct methanol fuel cell operated at high concentrations of methanol.

    PubMed

    Feng, Yan; Liu, Hui; Yang, Jun

    2017-06-01

    Owing to the serious crossover of methanol from the anode to the cathode through the polymer electrolyte membrane, direct methanol fuel cells (DMFCs) usually use dilute methanol solutions as fuel. However, the use of high-concentration methanol is highly demanded to improve the energy density of a DMFC system. Instead of the conventional strategies (for example, improving the fuel-feed system, membrane development, modification of electrode, and water management), we demonstrate the use of selective electrocatalysts to run a DMFC at high concentrations of methanol. In particular, at an operating temperature of 80°C, the as-fabricated DMFC with core-shell-shell Au@Ag2S@Pt nanocomposites at the anode and core-shell Au@Pd nanoparticles at the cathode produces a maximum power density of 89.7 mW cm(-2) at a methanol feed concentration of 10 M and maintains good performance at a methanol concentration of up to 15 M. The high selectivity of the electrocatalysts achieved through structural construction accounts for the successful operation of the DMFC at high concentrations of methanol.

  10. Methanol as a gasoline extender: a critique.

    PubMed

    Wigg, E E

    1974-11-29

    The tests conducted with the three vehicles at different emission control levels suggest that, in the area of fuel economy and emissions, potential benefits with methanol blends are related to carburetion and are only significant in the case of the rich-operating cars built before emission control standards were imposed. Theoretical considerations related to methanol's leaning effect on carburetion support this conclusion. Potential advantages for methanol in these areas are therefore continuously diminishing as the older cars leave the roads. At present, these older cars use only about one-fourth of the totalc motor gasoline consumed and, before methanol could be used on a large scale, this fraction would be much smaller. The use of methanol in gasoline would almost certainly create severe product quality problems. Water contamination could lead to phase separation in the distribution system and possibly in the car tank as well, and this would require additional investment in fuel handling and blending equipment. Excess fuel volatility in hot weather may also have adverse effects on car performance if the methanol blends include typical concentrations of butanes and pentanes. Removal of these light hydrocarbon components would detract from methanol's role as a gasoline extender and if current fuel volatility specifications were maintained, its use could lead to a net loss in the total available energy for use in motor fuels. Car performance problems associated with excessively lean operation would also be expected in the case of a significant proportion of late-model cars which are adjusted to operate on lean fuel-air mixtures. If methanol does become available in large quantities, these factors suggest that it would be more practical to use it for purposes other than those related to the extending of motor gasoline, such as for gas turbines used for electric power generation. In this case, the "pure" methanol would act as a cleanburning fuel, having none of the

  11. Platinum particles dispersed poly(diphenylamine) modified electrode for methanol oxidation

    NASA Astrophysics Data System (ADS)

    Santhosh, P.; Gopalan, A.; Vasudevan, T.; Lee, Kwang-Pill

    2006-09-01

    A modified potentiostatic method, termed the 'pulse pontentiostatic method' (PPSM) was used to get nano fibrillar poly(diphenylamine) (PDPA) film on Indium tin oxide (ITO) coated glass electrode and also for making modified electrode with platinum particles dispersed in PDPA. Platinum clusters were electrodispersed under constant potential on PDPA films to obtain catalytic electrodes for methanol oxidation. Energy dispersive analysis of X-rays (EDAX) results showed that the Pt microparticles are deposited into PDPA film. Scanning electron micrograph, SEM images show that the deposition results spherical catalytic particles. X-ray photoelectron spectroscopy (XPS) results inform that the net electronic charge on carbon atom and also the imine/amine ratio was not affected by Pt loadings. The modification of electrode surface by nano fibular PDPA improves the electrocatalytic activity for methanol oxidation.

  12. Polyoxometalate-modified carbon nanotubes: new catalyst support for methanol electro-oxidation.

    PubMed

    Pan, Dawei; Chen, Jinhua; Tao, Wenyan; Nie, Lihua; Yao, Shouzhuo

    2006-06-20

    A new catalyst support, polyoxometalate-modified carbon nanotubes, is presented in this paper through the chemisorption between polyoxometalate and carbon. Pt and Pt-Ru nanoparticles were electrochemically deposited on polyoxometalate-modified carbon nanotubes electrodes, and their electrocatalytic properties for methanol electro-oxidation are investigated in detail. Due to the unique electrical properties of carbon nanotubes and the excellent redox properties and the high protonic conductivity of polyoxometalate, for the similar deposition charge of Pt and Pt-Ru catalysts, 1.4 times larger exchange current density, 1.5 times higher specific activity, and better cycle stabilities can be obtained at polyoxometalate-modified carbon nanotube electrodes as compared to the electrodes without polyoxometalate modification. These results show that polyoxometalate-modified carbon nanotubes as a new catalyst support have good potential application in direct methanol fuel cells.

  13. Biotechnological production of methanol from waste biomass

    SciTech Connect

    Kozak, R.; Morris, D.

    1995-12-01

    The production of methanol (CH{sub 3}OH) from waste biomass is possible through the use of genetically modified bacteria. The biomass to methanol conversion process makes use of a naturally occurring, direct aerobic enzymatic system referred to as oxidative demethylation. Methoxy groups are stripped off of lignin and lignin like plant substances (approximately fifty percent of all plant biomass) and hydrolyzed to form methanol. Since the biotech process is stoichiometric, potentially every methoxy group in the lignin feedstock can be converted to methanol fuel. Approximately 30-35% of lignin is a methoxy compound that can be converted. Biotechnological conversion could produce up to 100 gallons/ton or 20 billion gallons a year of methanol from waste biomass. Current work has focused on the genetic modification of the enzymatic conversion process to reach commercial production. The goals of this research are; increase product yields, implement an operon {open_quotes}switch{close_quotes} mechanism to exploit multiple feedstocks, and produce environmentally safe by-products. Progress on these topics will be reported.

  14. Far-infrared Intensity Measurements of Methanol

    NASA Astrophysics Data System (ADS)

    Brauer, Carolyn; Sung, K.; Pearson, J. C.; Brown, L. R.; Xu, L. H.

    2009-12-01

    Line intensities of methanol (CH3OH) are generally derived using the dipole moments determined from Stark effect measurements. However, the rotational intensities typically do not account for the torsional dependence of the dipole moment, and are thus incomplete. This effect may be significant in some transitions and can lead to confusion in interpreting observational data. Given the expectations associated with modern observation facilities such as Herschel, ALMA and SOFIA, and the ubiquity of methanol in interstellar gas, precise knowledge of the methanol spectrum is critical. Furthermore, methanol has been used as a calibration gas for the Herschel HIFI instrument and precision intensity data facilitates calibration of the relative sideband gain and local oscillator mixer standing wave patterns. Because the torsional dependence of the dipole moment cannot be accurately calculated, it must be extracted from line intensity measurements. In this work, an empirical database of methanol line intensities from 300 to 500 cm-1 has been compiled from far-infrared measurements recorded on the Bruker IFS 125 HR Fourier transform spectrometer located at the Jet Propulsion Laboratory. This room temperature spectrum was taken at resolutions between 0.0014 and 0.0050 cm-1 using a 20.26 cm glass cell with wedged high-density polyethylene windows, and detected with a He-cooled bolometer. The results from this study will support the analyses of astronomical observations taken from orbit by the Herschel HIFI instrument.

  15. Stabilization of methanol-containing gasolines

    SciTech Connect

    Lykov, O.P.

    1994-09-01

    In other countries, methanol is used quite extensively as a component of automotive gasolines. The possibility of using methanol-containing gasolines in this country is currently under investigation. One of the basic problems in using such gasolines is their separation into phases at low temperatures when even traces of water are present. The temperature at which layer separation occurs can be lowered by the use of stabilizers such as isopropanol, isobutanol, 2-ethylhexanol, and other lower alcohols. The considerable difference between gasoline and methanol in physicochemical properties makes it necessary to use stabilizers in large amounts, up to 50% of the methanol content. The cost of stabilizers (C{sub 3}-C{sub 8} alcohols) is more than an order of magnitude higher than the cost of gasoline, and the availability of such alcohols in this country is quite limited. Because of this situation, it is of definite interest to develop new, effective stabilizers. The curtailment of oil production in this country has created a need for alternative fuels, including automotive gasolines. One possibility is the use of stabilized hydrocarbon-methanol blends (HMBs) based on waste materials from certain large-scale petrochemical production operations.

  16. Opportunities for coal to methanol conversion

    SciTech Connect

    Not Available

    1980-04-01

    The accumulations of mining residues in the anthracite coal regions of Pennsylvania offer a unique opportunity to convert the coal content into methanol that could be utilized in that area as an alternative to gasoline or to extend the supplies through blending. Additional demand may develop through the requirements of public utility gas turbines located in that region. The cost to run this refuse through coal preparation plants may result in a clean coal at about $17.00 per ton. After gasification and synthesis in a 5000 ton per day facility, a cost of methanol of approximately $3.84 per million Btu is obtained using utility financing. If the coal is to be brought in by truck or rail from a distance of approximately 60 miles, the cost of methanol would range between $4.64 and $5.50 per million Btu depending upon the mode of transportation. The distribution costs to move the methanol from the synthesis plant to the pump could add, at a minimum, $2.36 per million Btu to the cost. In total, the delivered cost at the pump for methanol produced from coal mining wastes could range between $6.20 and $7.86 per million Btu.

  17. Improved Anode for a Direct Methanol Fuel Cell

    NASA Technical Reports Server (NTRS)

    Valdez, Thomas; Narayanan, Sekharipuram

    2005-01-01

    A modified chemical composition has been devised to improve the performance of the anode of a direct methanol fuel cell. The main feature of the modified composition is the incorporation of hydrous ruthenium oxide into the anode structure. This modification can reduce the internal electrical resistance of the cell and increase the degree of utilization of the anode catalyst. As a result, a higher anode current density can be sustained with a smaller amount of anode catalyst. These improvements can translate into a smaller fuel-cell system and higher efficiency of conversion. Some background information is helpful for understanding the benefit afforded by the addition of hydrous ruthenium oxide. The anode of a direct methanol fuel cell sustains the electro-oxidation of methanol to carbon dioxide in the reaction CH3OH + H2O--->CO2 + 6H(+) + 6e(-). An electrocatalyst is needed to enable this reaction to occur. The catalyst that offers the highest activity is an alloy of approximately equal numbers of atoms of the noble metals platinum and ruthenium. The anode is made of a composite material that includes high-surface-area Pt/Ru alloy particles and a proton-conducting ionomeric material. This composite is usually deposited onto a polymer-electrolyte (proton-conducting) membrane and onto an anode gas-diffusion/current-collector sheet that is subsequently bonded to the proton-conducting membrane by hot pressing. Heretofore, the areal density of noble-metal catalyst typically needed for high performance has been about 8 mg/cm2. However, not all of the catalyst has been utilized in the catalyzed electro-oxidation reaction. Increasing the degree of utilization of the catalyst would make it possible to improve the performance of the cell for a given catalyst loading and/or reduce the catalyst loading (thereby reducing the cost of the cell). The use of carbon and possibly other electronic conductors in the catalyst layer has been proposed for increasing the utilization of the

  18. 3D anodes for direct methanol fuel cells: Science and synthesis

    NASA Astrophysics Data System (ADS)

    Takmeel, Qanit

    The high specific energy density of methanol in direct methanol fuel cells (DMFCs) makes them particularly suitable for portable applications. However, a typical DMFC membrane electrode assembly (MEA) delivers an order of magnitude less power density compared to a hydrogen fuel cell MEA. Conventional DMFCs are operated at dilute methanol concentrations to counter problems arising from the methanol crossover issue. A breakthrough in power density can be achieved if the MEA structure is fundamentally altered to enable supply of more concentrated methanol than in current DMFCs. It has been shown that the current anode designs are limited by mass transport resulting in low current density. [1] An anode, with manifold increase in surface area, for catalysis would increase the limiting current density (jL), as a result of which the power density of the fuel cell would increase. In this work, the role of layering of Pt on Ru was studied and this lay the foundation towards understanding catalytic behavior in the fuel cell anode. Cyclic voltammetry (CV), in conjunction with copper underpotential deposition (Cu-UPD) and 15 kelvin probe force microscopy (KPFM), showed that by adjusting the thickness of Pt on a Ru substrate, the Fermi energy (EF) of the surface can be tailored to yield more efficient methanol electro-oxidizing catalysts. In order to increase the effective catalysis surface area, three-dimensional (3D) carbon based hierarchical structures were fabricated on which Pt-Ru catalyst was grown using atomic layer deposition (ALD). Scanning electron microscopy (SEM), with image processing, was used to determine the surface coverage of the carbon surfaces. CV showed that as much as hundred times the current density (j) can be achieved with such a structure as compared to a flat surface. Subsequently, mass transport limitations were studied via chronoamperometry (CA) performed in different methanol concentrations. The studies were also used to extract the rate order of

  19. PEDOT:PSS self-assembled films to methanol crossover reduction in Nafion® membranes

    NASA Astrophysics Data System (ADS)

    Almeida, Tiago P.; Miyazaki, Celina M.; Paganin, Valdecir A.; Ferreira, Marystela; Saeki, Margarida J.; Perez, Joelma; Riul, Antonio

    2014-12-01

    Alternative energy sources are on a global demand, with fuel cells as promising devices from mobile to stationary applications. Nafion® is at the heart of many of these appliances, being mostly used due to its high proton conduction and good chemical stability at ambient temperature in proton exchange membranes (PEM). Therefore, methanol permeation throughout Nafion® films reduces drastically the performance of direct methanol fuel cells (DMFC). We present here the deposition of layer-by-layer (LbL) nanostructured thin films of poly(allylamine hydrochloride) (PAH) and poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) onto commercial Nafion® 212 membranes. It was observed a good adherence of the LbL films onto Nafion® 212, with UV-vis results displaying a linear characteristic growth, indicative that the same amount of material was deposited at each deposition step during the layer-by-layer assembly. In addition, the LbL films also act as a good barrier to avoid methanol crossover, with an observed reduction in the methanol permeation from 5.5 × 10-6 cm2 s-1 to 3.2 × 10-6 cm2 s-1, respectively to pristine Nafion® 212 and a 5-bilayer PAH/PEDOT:PSS LbL film deposited on Nafion®212. The measured power density in a DMFC set-up was not significantly changed (∼12 mW cm-2) due to the LbL films, since the PAH/PEDOT:PSS nanostructure is impeding water and ion transport, consequently affecting the proton conduction throughout the membrane.

  20. Methanol Emission from Leaves (Enzymatic Detection of Gas-Phase Methanol and Relation of Methanol Fluxes to Stomatal Conductance and Leaf Development).

    PubMed Central

    Nemecek-Marshall, M.; MacDonald, R. C.; Franzen, J. J.; Wojciechowski, C. L.; Fall, R.

    1995-01-01

    We recently reported the detection of methanol emissions from leaves (R. MacDonald, R. Fall [1993] Atmos Environ 27A: 1709-1713). This could represent a substantial flux of methanol to the atmosphere. Leaf methanol production and emission have not been investigated in detail, in part because of difficulties in sampling and analyzing methanol. In this study we used an enzymatic method to convert methanol to a fluorescent product and verified that leaves from several species emit methanol. Methanol was emitted almost exclusively from the abaxial surfaces of hypostomatous leaves but from both surfaces of amphistomatous leaves, suggesting that methanol exits leaves via stomates. The role of stomatal conductance was verified in experiments in which stomates were induced to close, resulting in reduced methanol. Free methanol was detected in bean leaf extracts, ranging from 26.8 [mu]g g-1 fresh weight in young leaves to 10.0 [mu]g g-1 fresh weight in older leaves. Methanol emission was related to leaf development, generally declining with increasing leaf age after leaf expansion; this is consistent with volatilization from a cellular pool that declines in older leaves. It is possible that leaf emission could be a major source of methanol found in the atmosphere of forests. PMID:12228547

  1. Thermally integrated staged methanol reformer and method

    DOEpatents

    Skala, Glenn William; Hart-Predmore, David James; Pettit, William Henry; Borup, Rodney Lynn

    2001-01-01

    A thermally integrated two-stage methanol reformer including a heat exchanger and first and second reactors colocated in a common housing in which a gaseous heat transfer medium circulates to carry heat from the heat exchanger into the reactors. The heat transfer medium comprises principally hydrogen, carbon dioxide, methanol vapor and water vapor formed in a first stage reforming reaction. A small portion of the circulating heat transfer medium is drawn off and reacted in a second stage reforming reaction which substantially completes the reaction of the methanol and water remaining in the drawn-off portion. Preferably, a PrOx reactor will be included in the housing upstream of the heat exchanger to supplement the heat provided by the heat exchanger.

  2. Acute toxicity of methanol to mytilus edulis

    SciTech Connect

    Helmstetter, A.; Gamerdinger, A.P.; Pruell, R.J.

    1996-12-31

    Methanol is being promoted as an alternative fuel because of the clean air benefits of reduced carbon monoxide and other by-product emissions. In the event of an accidental spill or leakage from a storage tank, there is limited data available on the impact of alternative fuels on marine ecosystems. Before considering the impact of methanol on ecosystem processes, it is necessary to establish the acute toxicity. The blue mussel (Mytilus edulis) was selected for study because of its use as an indicator species of marine ecosystem health (Widdows and Donkin 1992). Our primary objective was to determine the LC-50 value of methanol to adult Mytilus edulis. We also not sublethal effects that were observed during the course of the 96-hr exposure. 16 refs., 1 fig. 3 tabs.

  3. Efficient green methanol synthesis from glycerol

    NASA Astrophysics Data System (ADS)

    Haider, Muhammad H.; Dummer, Nicholas F.; Knight, David W.; Jenkins, Robert L.; Howard, Mark; Moulijn, Jacob; Taylor, Stuart H.; Hutchings, Graham J.

    2015-12-01

    The production of biodiesel from the transesterification of plant-derived triglycerides with methanol has been commercialized extensively. Impure glycerol is obtained as a by-product at roughly one-tenth the mass of the biodiesel. Utilization of this crude glycerol is important in improving the viability of the overall process. Here we show that crude glycerol can be reacted with water over very simple basic or redox oxide catalysts to produce methanol in high yields, together with other useful chemicals, in a one-step low-pressure process. Our discovery opens up the possibility of recycling the crude glycerol produced during biodiesel manufacture. Furthermore, we show that molecules containing at least two hydroxyl groups can be converted into methanol, which demonstrates some aspects of the generality of this new chemistry.

  4. Sabic; Methanol shortfall threatens MTBE growth

    SciTech Connect

    Not Available

    1992-02-10

    This paper reports that a lack of methanol capacity in the mid-1990s could lead to shortages and limit production of methyl tertiary butyl ether, warns Abdullah Nojaidi, president of Sabic Marketing Ltd. It is estimated that world methanol demand will rise by about 5.6%/year in 1991-2000 fed by a jump of at least 20% in demand for MTBE. These averages are deceptive, because demand will explode in 1992-1993. Abdullah Nojaidi states that we are going to need every available gallon of methanol capacity to control pollution in the U.S., western and eastern Europe, Japan, and Asia...Unfortunately, new plants require long lead times, and those who want to see the right returns in advance are unlikely to have plants in place when demand starts to rise sharply in 1992 and 1993.

  5. Methanol and the productivity of tropical crops

    SciTech Connect

    Ferguson, T.U.

    1995-12-31

    Studies are being conducted in Trinidad and Tobago, St. Lucia and St. Kitts/Nevis to determine the effect of aqueous solutions of methanol on the growth and yield of a wide range of vegetable, field and perennial crops. The paper presents a summary of results to data for ten of the crops studied. Six of these crops, lettuce, sweet pepper, tomato, mango and breadfruit, have shown significant increases in growth or yield with methanol application, while others such as pigeon pea, rice, banana and cocoa have shown more limited responses. There appears to be some potential for the use of methanol in tropical crop production but further studies are required before this apparent potential can be harnessed.

  6. Methanol ice in the protostar GL 2136

    NASA Technical Reports Server (NTRS)

    Skinner, C. J.; Tielens, A. G. G. M.; Barlow, M. J.; Justtanont, K.

    1992-01-01

    We present ground-based spectra in the 10 and 20 micron atmospheric windows of the deeply embedded protostar GL 2136. These reveal narrow absorption features at 9.7 and 8.9 microns, which we ascribe to the CO-stretch and CH3 rock (respectively) of solid methanol in grain mantles. The peak position of the 9.7 micron band implies that methanol is an important ice mantle component. However, the CH3OH/H2O abundance ratio derived from the observed column densities is only 0.1. This discrepancy suggests that the solid methanol and water ice are located in independent grain components. These independent components may reflect chemical differentiation during grain mantle formation and/or partial outgassing close to the protostar.

  7. Dynamic signature of molecular association in methanol.

    PubMed

    Bertrand, C E; Self, J L; Copley, J R D; Faraone, A

    2016-07-07

    Quasielastic neutron scattering measurements and molecular dynamics simulations were combined to investigate the collective dynamics of deuterated methanol, CD3OD. In the experimentally determined dynamic structure factor, a slow, non-Fickian mode was observed in addition to the standard density-fluctuation heat mode. The simulation results indicate that the slow dynamical process originates from the hydrogen bonding of methanol molecules. The qualitative behavior of this mode is similar to the previously observed α-relaxation in supercooled water [M. C. Bellissent-Funel et al., Phys. Rev. Lett. 85, 3644 (2000)] which also originates from the formation and dissolution of hydrogen-bonded associates (supramolecular clusters). In methanol, however, this mode is distinguishable well above the freezing transition. This finding indicates that an emergent slow mode is not unique to supercooled water, but may instead be a general feature of hydrogen-bonding liquids and associating molecular liquids.

  8. Efficient green methanol synthesis from glycerol.

    PubMed

    Haider, Muhammad H; Dummer, Nicholas F; Knight, David W; Jenkins, Robert L; Howard, Mark; Moulijn, Jacob; Taylor, Stuart H; Hutchings, Graham J

    2015-12-01

    The production of biodiesel from the transesterification of plant-derived triglycerides with methanol has been commercialized extensively. Impure glycerol is obtained as a by-product at roughly one-tenth the mass of the biodiesel. Utilization of this crude glycerol is important in improving the viability of the overall process. Here we show that crude glycerol can be reacted with water over very simple basic or redox oxide catalysts to produce methanol in high yields, together with other useful chemicals, in a one-step low-pressure process. Our discovery opens up the possibility of recycling the crude glycerol produced during biodiesel manufacture. Furthermore, we show that molecules containing at least two hydroxyl groups can be converted into methanol, which demonstrates some aspects of the generality of this new chemistry.

  9. Methanol sensor operated in a passive mode

    DOEpatents

    Ren, Xiaoming; Gottesfeld, Shimshon

    2002-01-01

    A sensor outputs a signal related to a concentration of methanol in an aqueous solution adjacent the sensor. A membrane electrode assembly (MEA) is included with an anode side and a cathode side. An anode current collector supports the anode side of the MEA and has a flow channel therethrough for flowing a stream of the aqueous solution and forms a physical barrier to control access of the methanol to the anode side of the MEA. A cathode current collector supports the cathode side of the MEA and is configured for air access to the cathode side of the MEA. A current sensor is connected to measure the current in a short circuit across the sensor electrodes to provide an output signal functionally related to the concentration of methanol in the aqueous solution.

  10. Olefins from methanol by modified zeolites

    SciTech Connect

    Inui, T.; Takegami, Y.

    1982-11-01

    Compares the effects of modified catalysts (ZSM-34 and ZSM-5 class zeolites) on methanol conversion to olefins (MTO) with regard to olefin selectivity and cost. Presents tables with prices of olefins in the US and Japan; comparison of methanol-cracking with naphtha cracking; methanol conversion data for Type-1, Type-II and reference catalysts; hydrocarbon distribution from MTO processes; and speculative economics for MTO processes of Concept-1 and 2. Diagrams the proposed MTO process scheme. Scanning electron micrographs of the zeolite catalysts are shown. Graphs indicate the change of ethylene prices in the US since 1978 and forecast ethylene prices in several countries. Concludes that the prices of ethylene for both MTO processes examined compare favorably with products of conventional processes.

  11. Photocatalytic conversion of methane to methanol

    SciTech Connect

    Taylor, C.E.; Noceti, R.P.; D`Este, J.R.

    1995-12-31

    A long-term goal of our research group is the exploration of novel pathways for the direct oxidation of methane to liquid fuels, chemicals, and intermediates. The use of three relatively abundant and inexpensive reactants, light, water, and methane, to produce methanol is attractive. The products of reaction, methanol and hydrogen, are both commercially desirable, methanol being used as is or converted to a variety of other chemicals, and the hydrogen could be utilized in petroleum and/or chemical manufacturing. Methane is produced as a by-product of coal gasification. Depending upon reactor design and operating conditions, up to 18% of total gasifier product may be methane. In addition, there are vast proven reserves of geologic methane in the world. Unfortunately, a large fraction of these reserves are in regions where there is little local demand for methane and it is not economically feasible to transport it to a market. There is a global research effort under way in academia, industry, and government to find methods to convert methane to useful, more readily transportable and storable materials. Methanol, the initial product of methane oxidation, is a desirable product of conversion because it retains much of the original energy of the methane while satisfying transportation and storage requirements. Investigation of direct conversion of methane to transportation fuels has been an ongoing effort at PETC for over 10 years. One of the current areas of research is the conversion of methane to methanol, under mild conditions, using light, water, and a semiconductor photocatalyst. The use of three relatively abundant and inexpensive reactants, light, water, and methane, to produce methanol, is attractive. Research in the laboratory is directed toward applying the techniques developed for the photocatalytic splitting of the water and the photochemical conversion of methane.

  12. Neuromuscular Functions on Experimental Acute Methanol Intoxication

    PubMed Central

    Moral, Ali Reşat; Çankayalı, İlkin; Sergin, Demet; Boyacılar, Özden

    2015-01-01

    Objective The incidence of accidental or suicidal ingestion of methyl alcohol is high and methyl alcohol intoxication has high mortality. Methyl alcohol intoxication causes severe neurological sequelae and appears to be a significant problem. Methyl alcohol causes acute metabolic acidosis, optic neuropathy leading to permanent blindness, respiratory failure, circulatory failure and death. It is metabolised in the liver, and its metabolite formic acid has direct toxic effects, causing oxidative stress, mitochondrial damage and increased lipid peroxidation associated with the mechanism of neurotoxicity. Methanol is known to cause acute toxicity of the central nervous system; however, the effects on peripheral neuromuscular transmission are unknown. In our study, we aimed to investigate the electrophysiological effects of experimentally induced acute methanol intoxication on neuromuscular transmission in the early period (first 24 h). Methods After approval by the Animal Experiment Ethics Committee of Ege University, the study was carried out on 10 Wistar rats, each weighing about 200 g. During electrophysiological recordings and orogastric tube insertion, the rats were anaesthetised using intra-peritoneal (IP) injection of ketamine 100 mg kg−1 and IP injection of xylazine 10 mg kg−1. The rats were given 3 g kg−1 methyl alcohol by the orogastric tube. Electrophysiological measurements from the gastrocnemius muscle were compared with baseline. Results Latency measurements before and 24 h after methanol injection were 0.81±0.11 ms and 0.76±0.12 ms, respectively. CMAP amplitude measurements before and 24 h after methanol injection were 9.85±0.98 mV and 9.99±0.40 mV, respectively. CMAP duration measurements before and 24 h after methanol injection were 9.86±0.03 ms and 9.86±0.045 ms, respectively. Conclusion It was concluded that experimental methanol intoxication in the acute phase (first 24 h) did not affect neuromuscular function. PMID:27366524

  13. Spontaneous Symmetry Breaking

    NASA Astrophysics Data System (ADS)

    Strocchi, Franco

    One of the most powerful ideas of modern theoretical physics is the mechanism of spontaneous symmetry breaking. It is at the basis of most of the recent achievements in the description of phase transitions in Statistical Mechanics as well as of collective phenomena in solid state physics. It has also made possible the unification of weak, electromagnetic and strong interactions in elementary particle physics. Philosophically, the idea is very deep and subtle (this is probably why its exploitation is a rather recent achievement) and the popular accounts do not fully do justice to it.

  14. Spontaneous cerebrospinal fluid rhinorrhea.

    PubMed

    Yerkes, S A; Thompson, D H; Fisher, W S

    1992-07-01

    The diagnosis of CSF rhinorrhea requires the performance of a thorough history and physical examination. Often no objective findings can be found and further evaluation will be required. In our experience, metrizamide CT cisternography yields the most information for localization of the fistula. When indicated, patients can be protected against meningitis by using prophylactic antibiotics for 4-6 weeks to allow a fistula to close spontaneously. If the fistula fails to close during this time, surgical closure with dural or muscle graft with or without waxing of the bone is the treatment of choice.

  15. A novel process for methanol synthesis

    SciTech Connect

    Tierney, J.W.; Wender, I.

    1992-01-01

    A bench-scale reactor is being used to study the conversion of synthesis gas to methanol (MEOH) in the liquid phase by a novel method. In previous reports, we provided evidence for a two step reaction consisting of a carbonylation reaction taking place mainly in the film'' close to a copper chromite surface followed by a hydrogenolysis reaction taking place on the surface of the copper chromite. The interaction between the two catalysts enhances the rate of methanol formation. In this quarter, we reexamined the equilibrium concentration for methyl formate and obtained data at higher loadings of copper chromite.

  16. Neat methanol fuel cell power plant

    NASA Astrophysics Data System (ADS)

    Abens, S.; Farooque, M.

    1985-12-01

    Attention is given to a fuel cell development effort which has been directed, by ease-of-supply, low weight, and low volume criteria toward the use of undiluted methanol. Partial oxidation and internal water recovery concepts are incorporated, allowing the onboard dilution of methanol fuel through mixing with exhaust-recovered water. This scheme is successfully demonstrated for the case of a 3 kW unit employing commercial cross flow heat exchangers, as well as for a 5 kW reformer flue exhaust water recovery design with U.S. Air force baseload stationary applications. The USAF powerplant has an overall thermal efficiency of 32 percent at rated load.

  17. Environmental controls over methanol emission from leaves

    NASA Astrophysics Data System (ADS)

    Harley, P.; Greenberg, J.; Niinemets, É.; Guenther, A.

    2007-12-01

    Methanol is found throughout the troposphere, with average concentrations second only to methane among atmospheric hydrocarbons. Proposed global methanol budgets are highly uncertain, but all agree that at least 60% of the total source arises from the terrestrial biosphere and primary emissions from plants. However, the magnitude of these emissions is also highly uncertain, and the environmental factors which control them require further elucidation. Using a temperature-controlled leaf enclosure, we measured methanol emissions from leaves of six plant species by proton transfer reaction mass spectrometry, with simultaneous measurements of leaf evapotranspiration and stomatal conductance. Rates of emission at 30°C varied from 0.2 to 38 μg g (dry mass)-1 h-1, with higher rates measured on young leaves, consistent with the production of methanol via pectin demethylation in expanding foliage. On average, emissions increased by a factor of 2.3 for each 10°C increase in leaf temperature. At constant temperature, emissions were also correlated with co-varying incident photosynthetic photon flux density and rates of stomatal conductance. The data were analyzed using the emission model developed by Niinemets and Reichstein (2003a, b), with the incorporation of a methanol production term that increased exponentially with temperature. It was concluded that control of emissions, during daytime, was shared by leaf temperature and stomatal conductance, although rates of production may also vary diurnally in response to variations in leaf growth rate in expanding leaves. The model, which generally provided reasonable simulations of the measured data during the day, significantly overestimated emissions on two sets of measurements made through the night, suggesting that production rates of methanol were reduced at night, perhaps because leaf growth was reduced or possibly through a direct effect of light on production. Although the short-term dynamics of methanol emissions can

  18. 37 GHz METHANOL MASERS : HORSEMEN OF THE APOCALYPSE FOR THE CLASS II METHANOL MASER PHASE?

    SciTech Connect

    Ellingsen, S. P.; Breen, S. L.; Sobolev, A. M.; Voronkov, M. A.; Caswell, J. L.; Lo, N.

    2011-12-01

    We report the results of a search for class II methanol masers at 37.7, 38.3, and 38.5 GHz toward a sample of 70 high-mass star formation regions. We primarily searched toward regions known to show emission either from the 107 GHz class II methanol maser transition, or from the 6.035 GHz excited OH transition. We detected maser emission from 13 sources in the 37.7 GHz transition, eight of these being new detections. We detected maser emission from three sources in the 38 GHz transitions, one of which is a new detection. We find that 37.7 GHz methanol masers are only associated with the most luminous 6.7 and 12.2 GHz methanol maser sources, which in turn are hypothesized to be the oldest class II methanol sources. We suggest that the 37.7 GHz methanol masers are associated with a brief evolutionary phase (of 1000-4000 years) prior to the cessation of class II methanol maser activity in the associated high-mass star formation region.

  19. A novel preparation method of Sn-modified Pt nanoparticles and application for methanol oxidation

    NASA Astrophysics Data System (ADS)

    Du, Yongling; Su, Biquan; Zhang, Nuo; Wang, Chunming

    2008-12-01

    With polystyrene latex spheres self-assembled on ITO glass as templates, highly ordered two-dimensional (2D) Pt nanoparticles (PtNPs) were prepared by electrochemical deposition. The morphology and element composition of PtNPs were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The electrocatalytic properties of PtNPs/ITO and Sn underpotential deposition (UPD) modified PtNPs/ITO for methanol oxidation has been investigated by cyclic voltammetry (CV) and chronoamperometry (CA). The excellent electrocatalytic activity can be observed for these catalytic systems.

  20. Simultaneous Observation of Water and Class I Methanol Masers toward Class II Methanol Maser Sources

    NASA Astrophysics Data System (ADS)

    Kang, Hyunwoo; Kim, Kee-Tae; Byun, Do-Young; Lee, Seokho; Park, Yong-Sun

    2015-11-01

    We present a simultaneous single-dish survey of 22 GHz water masers and 44 and 95 GHz class I methanol masers toward 77 6.7 GHz class II methanol maser sources, which were selected from the Arecibo methanol maser Galactic plane survey catalog. Water maser emission is detected in 39 (51%) sources, 15 of which are new detections. Methanol maser emission at 44 and 95 GHz is found in 25 (32%) and 19 (25%) sources, 21 and 13 of which, respectively, are newly detected. We find four high-velocity (>30 km s-1) water maser sources, including three dominant blue- or redshifted outflows. The 95 GHz masers always appear with 44 GHz maser emission. They are strongly correlated with 44 GHz masers in velocity, flux density, and luminosity, yet they are not correlated with either water or 6.7 GHz class II methanol masers. The average peak flux density ratio of 95 GHz masers to 44 GHz masers is close to unity, which is two times higher than previous estimates. The flux densities of class I methanol masers are more closely correlated with the associated Bolocam Galactic Plane Survey core mass than those of water masers or class II methanol masers. Using the large velocity gradient model and assuming unsaturated class I methanol maser emission, we derive the fractional abundance of methanol to be in the range 4.2 × 10-8-2.3 × 10-6, with a median value of 3.3 ± 2.7 × 10-7.

  1. Order in Spontaneous Behavior

    PubMed Central

    Maye, Alexander; Hsieh, Chih-hao; Sugihara, George; Brembs, Björn

    2007-01-01

    Brains are usually described as input/output systems: they transform sensory input into motor output. However, the motor output of brains (behavior) is notoriously variable, even under identical sensory conditions. The question of whether this behavioral variability merely reflects residual deviations due to extrinsic random noise in such otherwise deterministic systems or an intrinsic, adaptive indeterminacy trait is central for the basic understanding of brain function. Instead of random noise, we find a fractal order (resembling Lévy flights) in the temporal structure of spontaneous flight maneuvers in tethered Drosophila fruit flies. Lévy-like probabilistic behavior patterns are evolutionarily conserved, suggesting a general neural mechanism underlying spontaneous behavior. Drosophila can produce these patterns endogenously, without any external cues. The fly's behavior is controlled by brain circuits which operate as a nonlinear system with unstable dynamics far from equilibrium. These findings suggest that both general models of brain function and autonomous agents ought to include biologically relevant nonlinear, endogenous behavior-initiating mechanisms if they strive to realistically simulate biological brains or out-compete other agents. PMID:17505542

  2. Liquid phase methanol reactor staging process for the production of methanol

    SciTech Connect

    Bonnell, Leo W.; Perka, Alan T.; Roberts, George W.

    1988-01-01

    The present invention is a process for the production of methanol from a syngas feed containing carbon monoxide, carbon dioxide and hydrogen. Basically, the process is the combination of two liquid phase methanol reactors into a staging process, such that each reactor is operated to favor a particular reaction mechanism. In the first reactor, the operation is controlled to favor the hydrogenation of carbon monoxide, and in the second reactor, the operation is controlled so as to favor the hydrogenation of carbon dioxide. This staging process results in substantial increases in methanol yield.

  3. Controllable Deposition of Alloy Clusters or Nanoparticles Catalysts on Carbon Surfaces

    SciTech Connect

    Sasaki, K.; Ando, Y.; Su, D.; Adzic, R.

    2011-08-15

    We describe a simple method for controllably depositing Pt-Ru alloy nanoparticles on carbon surfaces that is mediated by Pb or Cu adlayers undergoing underpotential deposition and stripping during Pt and Ru codeposition at diffusion-limiting currents. The amount of surface Pt atoms deposited largely reflects the number of potential cycles causing the deposition and stripping of the metal adlayer at underpotentials, the metal species used as a mediator, and the scan rate of the potential cycles. We employed electrochemical methanol oxidation to gain information on the catalyst's activities. The catalysts with large amounts of surface Pt atoms have relatively high methanol-oxidation activity. Catalysts prepared using this method enhance methanol-oxidation activity per electrode surface area, while maintaining catalytic activity per surface Pt atom; thus, the amount of Pt is reduced in comparison with conventional methanol-oxidation catalysts. The method is suitable for efficient synthesizing various bimetallic catalysts.

  4. The Acid Catalyzed Nitration of Methanol: Formation of Methyl Nitrate via Aerosol Chemistry

    NASA Technical Reports Server (NTRS)

    Riffel, Brent G.; Michelsen, Rebecca R.; Iraci, Laura T.

    2004-01-01

    The liquid phase acid catalyzed reaction of methanol with nitric acid to yield methyl nitrate under atmospheric conditions has been investigated using gas phase infrared spectroscopy. This nitration reaction is expected to occur in acidic aerosol particles found in the upper troposphere/lower stratosphere as highly soluble methanol and nitric acid diffuse into these aerosols. Gaseous methyl nitrate is released upon formation, suggesting that some fraction of NO(x) may he liberated from nitric acid (methyl nitrate is later photolyzed to NO(x)) before it is removed from the atmosphere by wet deposition. Thus, this reaction may have important implications for the NO(x) budget. Reactions have been initiated in 45-62 wt% H2SO4 solutions at 10.0 C. Methyl nitrate production rates increased exponentially with acidity within the acidity regime studied. Preliminary calculations suggest that the nitronium ion (NO2(+) is the active nitrating agent under these conditions. The reaction order in methanol appears to depend on the water/methanol ratio and varies from first to zeroth order under conditions investigated. The nitration is first order in nitronium at all acidities investigated. A second order rate constant, kappa(sub 2), has been calculated to be 1 x 10(exp 8)/ M s when the reaction is first order in methanol. Calculations suggest the nitration is first order in methanol under tropospheric conditions. The infinitesimal percentage of nitric acid in the nitronium ion form in this acidity regime probably makes this reaction insignificant for the upper troposphere; however, this nitration may become significant in the mid stratosphere where colder temperatures increase nitric acid solubility and higher sulfuric acid content shifts nitric acid speciation toward the nitronium ion.

  5. The Acid Catalyzed Nitration of Methanol: Formation of Methyl Nitrate via Aerosol Chemistry

    NASA Technical Reports Server (NTRS)

    Riffel, Brent G.; Michelsen, Rebecca R.; Iraci, Laura T.

    2004-01-01

    The liquid phase acid catalyzed reaction of methanol with nitric acid to yield methyl nitrate under atmospheric conditions has been investigated using gas phase infrared spectroscopy. This nitration reaction is expected to occur in acidic aerosol particles found in the upper troposphere/lower stratosphere as highly soluble methanol and nitric acid diffuse into these aerosols. Gaseous methyl nitrate is released upon formation, suggesting that some fraction of NO(x) may he liberated from nitric acid (methyl nitrate is later photolyzed to NO(x)) before it is removed from the atmosphere by wet deposition. Thus, this reaction may have important implications for the NO(x) budget. Reactions have been initiated in 45-62 wt% H2SO4 solutions at 10.0 C. Methyl nitrate production rates increased exponentially with acidity within the acidity regime studied. Preliminary calculations suggest that the nitronium ion (NO2(+) is the active nitrating agent under these conditions. The reaction order in methanol appears to depend on the water/methanol ratio and varies from first to zeroth order under conditions investigated. The nitration is first order in nitronium at all acidities investigated. A second order rate constant, kappa(sub 2), has been calculated to be 1 x 10(exp 8)/ M s when the reaction is first order in methanol. Calculations suggest the nitration is first order in methanol under tropospheric conditions. The infinitesimal percentage of nitric acid in the nitronium ion form in this acidity regime probably makes this reaction insignificant for the upper troposphere; however, this nitration may become significant in the mid stratosphere where colder temperatures increase nitric acid solubility and higher sulfuric acid content shifts nitric acid speciation toward the nitronium ion.

  6. Role of retinal metabolism in methanol-induced retinal toxicity

    SciTech Connect

    Garner, C.D. |; Lee, E.W.; Terzo, T.S.; Louis-Ferdinand, R.T.

    1995-08-01

    Methanol is a toxicant that causes systemic and ocular toxicity after acute exposure. The folate-reduced (FR) rat is an excellent animal model that mimics characteristic human methanol toxic responses. The present study examines the role of the methanol metabolites formaldehyde and formate in the initiation of methanol-induced retinal toxicity. After a single oral dose of 3.0 g/kg methanol, blood methanol concentrations were not significantly different in FR rats compared with folate-sufficient (FS) (control) rats. However, FR rats treated with 3.0 g/kg methanol displayed elevated blood (14.6 mM) and vitreous humor (19.5 mM) formate levels and abnormal electroretinograms (loss of b-wave) 48 h postdose. FR rats pretreated with disulfiram (DSF) prior to 3.0 g/kg methanol treatment failed to display these symptoms. Formaldehyde was not detected in blood or vitreous humor with or without DSF treatment, suggesting that formate is the toxic metabolite in methanol-induced retinal toxicity. Additionally, creating a blood formate profile (14.2 mM at 48 h) similar to that observed in methanol-treated rats by iv infusion of pH-buffered formate does not alter the electroretinogram as is observed with methanol treatment. These data suggest that intraretinal metabolism of methanol is necessary for the formate-mediated initiation of methanol-induced retinal toxicity. 31 refs., 5 figs., 2 tabs.

  7. Methanex, Hoechst Celanese dissolve methanol partnership

    SciTech Connect

    Morris, G.D.L.

    1993-03-31

    One of the many joint venture alliances recently announced in the petrochemical sector is ending in divorce. Hoechst Celanese Chemical (Dallas) and Methanex Corp. (Vancouver) are in the process of dissolving the partnership they had formed to restart Hoechst Celanese's methanol plant at Clear Lake, TX. Hoechst Celanese says it is actively seeking replacement partners and has several likely prospects, while Methanex is concentrating on its other ventures. Those include its just-completed acquisition of Fletcher Challenge's (Auckland, NZ) methanol business and a joint venture with American Cyanamid to convert an ammonia plant at Fortier, LA to methanol. Methanex will still be the world's largest producer of methanol. Officially, the negotiations between Methanex and Hoechst Celanese just broke down over the last month or so,' says Steve Yurich, operations manager for the Clear Lake plant. Market sources, however, say that Methanex found itself with too many irons in the fire' and pulled out before it ran into financial or perhaps even antitrust difficulties.

  8. The Relative Acidities of Water and Methanol

    NASA Astrophysics Data System (ADS)

    Abrash, Henry I.

    2001-11-01

    The experimental evidence for the relative acidities of water and methanol is reviewed. Because of solvent effects, a comparison of either autoprotolysis constants or dissociation constants measured in different media does not provide a reliable indication of these relative values. The most suitable measure of the relative acidities of water and methanol is the equilibrium constant for the proton transfer between water and methoxide ion (H2O + CH3O- OHO- + CH3OH) in various water-methanol mixtures. Experimental measurements of this thermodynamic equilibrium constant, in particular the contributions of Unmack, show considerable uncertainty owing to the difficulties in estimating activity coefficients, but they strongly indicate that methanol is about twice as acidic as water. This result shows that substitution of a methyl group for a hydrogen atom does not always destabilize a negative charge on a nearby oxygen atom. The question of whether to present acidities, particularly those of solvents, in terms of dissociation constants based on concentrations rather than activities is considered. In view of the slight consideration given to the relative acidities of water and alcohols in current organic chemistry tests and the discontinuity for students caused by use of concentration-based constants in organic chemistry only, thermodynamic constants remain the most suitable way to present acidities.

  9. Direct methanol feed fuel cell and system

    NASA Technical Reports Server (NTRS)

    Surampudi, Subbarao (Inventor); Frank, Harvey A. (Inventor); Narayanan, Sekharipuram R. (Inventor); Chun, William (Inventor); Jeffries-Nakamura, Barbara (Inventor); Kindler, Andrew (Inventor); Halpert, Gerald (Inventor)

    2008-01-01

    Improvements to non acid methanol fuel cells include new formulations for materials. The platinum and ruthenium are more exactly mixed together. Different materials are substituted for these materials. The backing material for the fuel cell electrode is specially treated to improve its characteristics. A special sputtered electrode is formed which is extremely porous.

  10. HYDROGEN BONDING IN THE METHANOL DIMER

    USDA-ARS?s Scientific Manuscript database

    In this work, two methanol molecules are placed in different arrangements to study hydrogen bonding in carbohydrate materials such as cellulose. Energy was calculated as a function of both hydrogen bond length and angle over wide ranges, using quantum mechanics (QM). The QM wavefunctions are analyze...

  11. Approach to the Treatment of Methanol Intoxication.

    PubMed

    Kraut, Jeffrey A

    2016-07-01

    Methanol intoxication is an uncommon but serious poisoning. Its adverse effects are due primarily to the impact of its major metabolite formic acid and lactic acid resulting from cellular hypoxia. Symptoms including abdominal pain and loss of vision can appear a few hours to a few days after exposure, reflecting the time necessary for accumulation of the toxic byproducts. In addition to a history of exposure, increases in serum osmolal and anion gaps can be clues to its presence. However, increments in both parameters can be absent depending on the nature of the toxic alcohol, time of exposure, and coingestion of ethanol. Definitive diagnosis requires measurement with gas or liquid chromatography, which are laborious and expensive procedures. Tests under study to detect methanol or its metabolite formate might facilitate the diagnosis of this poisoning. Treatment can include administration of ethanol or fomepizole, both inhibitors of the enzyme alcohol dehydrogenase to prevent formation of its metabolites, and hemodialysis to remove methanol and formate. In this Acid-Base and Electrolyte Teaching Case, a patient with methanol intoxication due to ingestion of model airplane fuel is described, and the value and limitations of current and new diagnostic and treatment measures are discussed. Published by Elsevier Inc.

  12. A novel process for methanol synthesis

    SciTech Connect

    Tierney, J.W.; Wender, I.

    1991-01-01

    A bench-scale reactor is being used to conduct studies of the conversion of synthesis gas to methanol by a novel process. In previous reports, we provided evidence for a two step reaction in series, the carbonylation reaction mainly taking place in a non-equilibrium region in the vicinity of the Cu-chromite surface, and the hydrogenolysis reaction taking place on the surface of the Cu-chromite. The synergism between the two catalysts enhances the rate of methanol formation. In this quarter, we studied the effect of pressure and temperature on the rate of MeOH synthesis. We also compared the reaction rate of a syngas feed simulated for an H{sub 2}/CO ratio from a Texaco gasifier with a methanol balanced syngas feed (H{sub 2}/CO=2). Atomic absorption analysis of solid and liquid samples for the KOMe/Cu-chromite runs was undertaken to identify the distribution of potassium at the end of the methanol synthesis runs. Modelling studies were initiated with emphasis on both kinetic and process behavior. 12 refs., 7 figs., 1 tab.

  13. Molecular modeling in dioxane methanol interaction.

    PubMed

    Sharma, Dipti; Sahoo, Sagarika; Mishra, Bijay K

    2014-09-01

    Molecular interaction between dioxane and methanol involves certain polar and nonpolar bonding to form a one to one complex. Interatomic distances between hydrogen and oxygen within 3 Å have been considered as hydrogen bonding. Optimizations of the structures of dioxane-methanol complexes were carried out considering any spatial orientation of a methanol molecule around a chair/boat/twisted-boat conformation of dioxane. From 45 different orientations of dioxane and water, 23 different structures with different local minima were obtained and the structural characteristics like interatomic distances, bond angles, dihedral angles, dipole moment of each complex were discussed. The most stable structure, i.e., with minimum heat of formation is found to have a chair form dioxane, one O-H…O, and two C-H…O hydrogen bonds. In general, the O-H…O hydrogen bonds have an average distance of 1.8 Å while C-H…O bonds have 2.6 Å. The binding energy of the dioxane-methanol complex is found to be a linear function of number of O-H…O and C-H…O bonds, and hydrogen bond length.

  14. Direct methanol feed fuel cell and system

    NASA Technical Reports Server (NTRS)

    Surampudi, Subbarao (Inventor); Frank, Harvey A. (Inventor); Narayanan, Sekharipuram R. (Inventor); Chun, William (Inventor); Jeffries-Nakamura, Barbara (Inventor); Kindler, Andrew (Inventor); Halpert, Gerald (Inventor)

    2004-01-01

    Improvements to non acid methanol fuel cells include new formulations for materials. The platinum and ruthenium are more exactly mixed together. Different materials are substituted for these materials. The backing material for the fuel cell electrode is specially treated to improve its characteristics. A special sputtered electrode is formed which is extremely porous.

  15. Direct methanol feed fuel cell and system

    NASA Technical Reports Server (NTRS)

    Surampudi, Subbarao (Inventor); Frank, Harvey A. (Inventor); Narayanan, Sekharipuram R. (Inventor); Chun, William (Inventor); Jeffries-Nakamura, Barbara (Inventor); Kindler, Andrew (Inventor); Halpert, Gerald (Inventor)

    2000-01-01

    Improvements to non-acid methanol fuel cells include new formulations for materials. The platinum and ruthenium are more exactly mixed together. Different materials are substituted for these materials. The backing material for the fuel cell electrode is specially treated to improve its characteristics. A special sputtered electrode is formed which is extremely porous.

  16. A methanol/air fuel cell system

    NASA Technical Reports Server (NTRS)

    Asher, W. J.

    1974-01-01

    High power-density, self-regulating fuel cell develops electrical power from catalyzed reaction between methanol and atmospheric oxygen. Cells such as these are of particular interest, because they may one day offer an emission-free, extremely efficient alternative to internal-combustion engines as power source.

  17. Metacridamide B methanol-d4 monosolvate

    USDA-ARS?s Scientific Manuscript database

    The title compound was extracted from conidia of the fungus Metarhizium acridum. Crystals were obtained as a methanol-d4 solvate. The tail part of the 4-methylhexan-2-yl group exhibits disorder over two positions, with an occupancy ratio of 0.682 (9):0.318 (9). The crystal structure confirms the abs...

  18. Antihyperlipidemic effect of Casearia sylvestris methanolic extract.

    PubMed

    Schoenfelder, Tatiana; Pich, Claus T; Geremias, Reginaldo; Avila, Silvio; Daminelli, Elaine N; Pedrosa, Rozangela C; Bettiol, Jane

    2008-09-01

    Casearia sylvestris methanolic extract (MCE) was screened at doses of 125-500 mg/kg for its antihyperlipidemic activity. The antihyperlipidemic effect was evaluated in olive oil-loaded mice. Acute treatment caused inhibition in the triglyceride (TG) and serum lipase elevation-induced by 5 ml/kg of olive oil.

  19. Methanol decomposition bottoming cycle for IC engines

    NASA Technical Reports Server (NTRS)

    Purohit, G.; Houseman, J.

    1979-01-01

    This paper presents the concept of methanol decomposition using engine exhaust heat, and examines its potential for use in the operation of passenger cars, diesel trucks, and diesel-electric locomotives. Energy economy improvements of 10-20% are calculated over the representative driving cycles without a net loss in power. Some reductions in exhaust emissions are also projected.

  20. Producing methanol from CO[sub 2

    SciTech Connect

    Goehna, H.; Koenig, P. )

    1994-06-01

    Year after year, large quantities of carbon dioxide are emitted to the atmosphere from a variety of sources. Solutions are sought to reduce CO[sub 2] emissions or to reconvert released CO[sub 2] into energy sources or other industrially usable substances. Methanol can be produced from CO[sub 2] and hydrogen, and can be used either as a fuel or as a chemical raw material. If used as a fuel, it would in effect have the added environmental advantage of reducing consumption of fossil fuels. Currently, methanol is produced from syngas, a mixture of H[sub 2], CO, and CO[sub 2]. CO is the main carbon source in the commercial-scale process by which methanol can be produced under competitive economics from a mixture of CO[sub 2] and hydrogen. This complex undertaking requires the development of a suitable catalyst, optimization of process parameters, and an adjustment of Lurgi's proven methanol technology to the specific requirements. This paper discusses goals for the catalyst, optimizing process parameters, adjustment of the process technology, and economic analysis.

  1. Antibacterial activity of Thymus daenensis methanolic extract.

    PubMed

    Mojab, Faraz; Poursaeed, Mahshid; Mehrgan, Hadi; Pakdaman, Shima

    2008-07-01

    Medicinal plants are potential of antimicrobial compounds. The present study deals with the antibacterial activity of methanolic extract of Thymus daenensis. Aerial parts of the plant were collected from Alvand mountainside (Hamadan, Iran) in May 2005, air-dried and extracted by methanol. The dried extract was redissolved in methanol to make a 100 mg/ml solution and then filtered. Antibacterial activity of the extract was evaluated against various Gram-positive and Gram-negatives bacteria using disk diffusion technique. Blank paper disks were loaded with 40 microl of the methanol solution and then dried up. The impregnated disks were placed on Mueller-Hinton agar inoculated with bacterial suspension equal to 0.5 McFarland. The extract inhibited the growth Gram-positive bacteria, i.e., Staphylococcus aureus, Micrococcus luteus, Entrococcus faecalis, Streptococcus pyogenes, but it showed no activity against Gram-negative bacteria. The most significant effect was seen against S.aureus including MRSA, which are important nosocomial pathogens. MIC90 of the extract was determined against Gram-positive bacteria (3.12 mg/ml) and 11 MRSA strain (1.56 mg/ml).

  2. Direct methanol feed fuel cell and system

    NASA Technical Reports Server (NTRS)

    Surampudi, Subbarao (Inventor); Frank, Harvey A. (Inventor); Narayanan, Sekharipuram R. (Inventor); Chun, William (Inventor); Jeffries-Nakamura, Barbara (Inventor); Kindler, Andrew (Inventor); Halpert, Gerald (Inventor)

    2008-01-01

    Improvements to non acid methanol fuel cells include new formulations for materials. The platinum and ruthenium are more exactly mixed together. Different materials are substituted for these materials. The backing material for the fuel cell electrode is specially treated to improve its characteristics. A special sputtered electrode is formed which is extremely porous.

  3. Methanol Steam Reformer on a Silicon Wafer

    SciTech Connect

    Park, H; Malen, J; Piggott, T; Morse, J; Sopchak, D; Greif, R; Grigoropoulos, C; Havstad, M; Upadhye, R

    2004-04-15

    A study of the reforming rates, heat transfer and flow through a methanol reforming catalytic microreactor fabricated on a silicon wafer are presented. Comparison of computed and measured conversion efficiencies are shown to be favorable. Concepts for insulating the reactor while maintaining small overall size and starting operation from ambient temperature are analyzed.

  4. Direct methanol feed fuel cell and system

    NASA Technical Reports Server (NTRS)

    Surampudi, Subbarao (Inventor); Frank, Harvey A. (Inventor); Narayanan, Sekharipuram R. (Inventor); Chun, William (Inventor); Jeffries-Nakamura, Barbara (Inventor); Kindler, Andrew (Inventor); Halpert, Gerald (Inventor)

    2001-01-01

    Improvements to non acid methanol fuel cells include new formulations for materials. The platinum and ruthenium are more exactly mixed together. Different materials are substituted for these materials. The backing material for the fuel cell electrode is specially treated to improve its characteristics. A special sputtered electrode is formed which is extremely porous.

  5. Optimized fuel cell grade hydrogen from methanol

    NASA Astrophysics Data System (ADS)

    Choi, Yongtaek

    2003-10-01

    To evaluate reaction rates liar making hydrogen from methanol, kinetic studies of methanol decomposition, methanol steam reforming, water gas shift reaction, and CO selective oxidation have been performed. These reactions were studied in a micro reactor testing unit using a commercial Cu-ZnO/Al2O3 catalyst for the first three reactions and Pt-Fe/gamma-alumina catalyst for the last reaction. The activity tests were performed between 120˜325°C and atmospheric pressure with a range of feed rates and compositions. For methanol decomposition, water addition to the feed increased the yield of hydrogen and reduced the formation of by-products. XPS analysis of used catalyst samples and time on-stream data showed that the Cu2+ oxidation state of copper favors methanol decomposition. A simplified reaction network of 5 elementary reactions was proposed and all five rate expressions were obtained using non-linear least squares optimization, numerical integration of a one-dimensional PFR model, and extensive experimental data. Similar numerical analysis was carried out to obtain the rate expressions for methanol steam reaction, the water gas shift reaction, and CO selective oxidation. For the kinetics of the water gas shift reaction, an empirical rate expression was obtained from the experimental data. Based on a review of published work on the WGS reaction mechanism, our study found that a rate expression derived from a regenerative mechanism and another rate expression derived from adsorptive mechanism fit the experimental data equally well. For the kinetics of CO preferential oxidation, a reaction model in which three reactions (CO oxidation, H2 oxidation and the WGS reaction) occur simultaneously was chosen to predict the reactor performance. In particular the reverse water gas shift reaction had an important role when fitting the experimental data precisely and explained the selectivity decrease at higher reaction temperatures. Combining the three reactors and several

  6. Selectivity of Direct Methanol Fuel Cell Membranes

    PubMed Central

    Aricò, Antonino S.; Sebastian, David; Schuster, Michael; Bauer, Bernd; D’Urso, Claudia; Lufrano, Francesco; Baglio, Vincenzo

    2015-01-01

    Sulfonic acid-functionalized polymer electrolyte membranes alternative to Nafion® were developed. These were hydrocarbon systems, such as blend sulfonated polyetheretherketone (s-PEEK), new generation perfluorosulfonic acid (PFSA) systems, and composite zirconium phosphate–PFSA polymers. The membranes varied in terms of composition, equivalent weight, thickness, and filler and were investigated with regard to their methanol permeation characteristics and proton conductivity for application in direct methanol fuel cells. The behavior of the membrane electrode assemblies (MEA) was investigated in fuel cell with the aim to individuate a correlation between membrane characteristics and their performance in a direct methanol fuel cell (DMFC). The power density of the DMFC at 60 °C increased according to a square root-like function of the membrane selectivity. This was defined as the reciprocal of the product between area specific resistance and crossover. The power density achieved at 60 °C for the most promising s-PEEK-based membrane-electrode assembly (MEA) was higher than the benchmark Nafion® 115-based MEA (77 mW·cm−2 vs. 64 mW·cm−2). This result was due to a lower methanol crossover (47 mA·cm−2 equivalent current density for s-PEEK vs. 120 mA·cm−2 for Nafion® 115 at 60 °C as recorded at OCV with 2 M methanol) and a suitable area specific resistance (0.15 Ohm cm2 for s-PEEK vs. 0.22 Ohm cm2 for Nafion® 115). PMID:26610582

  7. Selectivity of Direct Methanol Fuel Cell Membranes.

    PubMed

    Aricò, Antonino S; Sebastian, David; Schuster, Michael; Bauer, Bernd; D'Urso, Claudia; Lufrano, Francesco; Baglio, Vincenzo

    2015-11-24

    Sulfonic acid-functionalized polymer electrolyte membranes alternative to Nafion(®) were developed. These were hydrocarbon systems, such as blend sulfonated polyetheretherketone (s-PEEK), new generation perfluorosulfonic acid (PFSA) systems, and composite zirconium phosphate-PFSA polymers. The membranes varied in terms of composition, equivalent weight, thickness, and filler and were investigated with regard to their methanol permeation characteristics and proton conductivity for application in direct methanol fuel cells. The behavior of the membrane electrode assemblies (MEA) was investigated in fuel cell with the aim to individuate a correlation between membrane characteristics and their performance in a direct methanol fuel cell (DMFC). The power density of the DMFC at 60 °C increased according to a square root-like function of the membrane selectivity. This was defined as the reciprocal of the product between area specific resistance and crossover. The power density achieved at 60 °C for the most promising s-PEEK-based membrane-electrode assembly (MEA) was higher than the benchmark Nafion(®) 115-based MEA (77 mW·cm(-2) vs. 64 mW·cm(-2)). This result was due to a lower methanol crossover (47 mA·cm(-2) equivalent current density for s-PEEK vs. 120 mA·cm(-2) for Nafion(®) 115 at 60 °C as recorded at OCV with 2 M methanol) and a suitable area specific resistance (0.15 Ohm cm² for s-PEEK vs. 0.22 Ohm cm² for Nafion(®) 115).

  8. Real-time mass spectrometric study of the methanol crossover in a direct methanol fuel cell

    SciTech Connect

    Wang, J.T.; Wasmus, S.; Savinell, R.F.

    1996-04-01

    The products of methanol crossover through the acid-doped polybenzimidazole polymer electrolyte membrane (PBI PEM) to the cathode of a prototype direct methanol fuel cell (DMFC) were analyzed using multipurpose electrochemical mass spectrometry (MPEMS) coupled to the cathode exhaust gas outlet. It was found that the methanol crossing over reacts almost quantitatively to CO{sub 2} at the cathode with the platinum of the cathode acting as a heterogeneous catalyst. The cathode open-circuit potential is inversely proportional to the amount of CO{sub 2} formed. A poisoning effect on the oxygen reduction also was found. Methods for the estimation of the methanol crossover rate at operating fuel cells are suggested.

  9. Evaluation of the Ramazzini Foundation Study of Methanol in Rats

    EPA Pesticide Factsheets

    Evaluation of the Ramazzini Foundation Study of Methanol in Rats: A Comparison of Diagnoses by the RF Study Pathologist and a Recent NTP Review Team, summarized by George Cruzan and submitted to the Methanol Institute

  10. Isothermal vapor-liquid equilibria for methanol + ethanol + water, methanol + water, and ethanol + water

    SciTech Connect

    Kurihara, Kiyofumi; Takeda, Kouichi; Kojima, Kazuo; Minoura, Tsuyoshi

    1995-05-01

    Isothermal vapor-liquid equilibria were measured for the ternary system methanol + ethanol + water and its constituent binary systems of methanol + water and ethanol + water at 323.15, 328.15, and 333.15 K. The apparatus that was used made it possible to control the measured temperature and total pressure by computer. The experimental binary data were correlated by the NRTL equation. The ternary system was predicted using the binary NRTL parameters with good accuracy.

  11. Spontaneous coronary artery dissection.

    PubMed

    Giacoppo, Daniele; Capodanno, Davide; Dangas, George; Tamburino, Corrado

    2014-07-15

    Spontaneous coronary artery dissection (SCAD) is a relatively rare and unexplored type of coronary disease. Although atherosclerosis, hormonal changes during pregnancy and connective tissue disorders might represent a sufficiently convincing explanation for some patients with SCAD, the many remaining cases display only a weak relationship with these causes. While on one side the clinical heterogeneity of SCAD masks a full understanding of their underlying pathophysiologic process, on the other side paucity of data and misleading presentations hamper the quick diagnosis and optimal management of this condition. A definite diagnosis of SCAD can be significantly facilitated by endovascular imaging techniques. In fact, intravascular ultrasound (IVUS) and optical coherence tomography (OCT) overcome the limitations of coronary angiography providing detailed endovascular morphologic information. In contrast, optimal treatment strategies for SCAD still represent a burning controversial question. Herein, we review the published data examining possible causes and investigating the best therapy for SCAD in different clinical scenarios.

  12. Methanol production from Eucalyptus wood chips. Final report

    SciTech Connect

    Fishkind, H.H.

    1982-06-01

    This feasibility study includes all phases of methanol production from seedling to delivery of finished methanol. The study examines: production of 55 million, high quality, Eucalyptus seedlings through tissue culture; establishment of a Eucalyptus energy plantation on approximately 70,000 acres; engineering for a 100 million gallon-per-day methanol production facility; potential environmental impacts of the whole project; safety and health aspects of producing and using methanol; and development of site specific cost estimates.

  13. An undercovered health threat in Turkey: transdermal methanol intoxication.

    PubMed

    Uca, Ali Ulvi; Kozak, Hasan Hüseyin; Altaş, Mustafa

    2015-01-01

    Methanol is a clear, colorless solvent used in antifreeze solutions, varnishes, cologne, copying machine fluids, perfume, spirit, paint, and fuel. Even small amounts of ingested methanol can cause acute permanent neurological dysfunction and irreversible blindness. Although there are many reports of methanol poisoning due to suicidal or accidental ingestion, reports of transdermal absorption are rare. We present a 68-year-old man with transdermal methanol intoxication applied to our hospital's emergency department with weakness, loss of vision, and altered state of consciousness.

  14. Low-temperature ceria-electrolyte solid oxide fuel cells for efficient methanol oxidation

    NASA Astrophysics Data System (ADS)

    Meng, Xie; Zhan, Zhongliang; Liu, Xuejiao; Wu, Hao; Wang, Shaorong; Wen, Tinglian

    Low temperature anode-supported solid oxide fuel cells with thin films of samarium-doped ceria (SDC) as electrolytes, graded porous Ni-SDC anodes and composite La 0.6Sr 0.4Co 0.2Fe 0.8O 3 (LSCF)-SDC cathodes are fabricated and tested with both hydrogen and methanol fuels. Power densities achieved with hydrogen are between 0.56 W cm -2 at 500 °C and 1.09 W cm -2 at 600 °C, and with methanol between 0.26 W cm -2 at 500 °C and 0.82 W cm -2 at 600 °C. The difference in the cell performance can be attributed to variation in the interfacial polarization resistance due to different fuel oxidation kinetics, e.g., 0.21 Ω cm 2 for methanol versus 0.10 Ω cm 2 for hydrogen at 600 °C. Further analysis suggests that the leakage current densities as high as 0.80 A cm -2 at 600 °C and 0.11 A cm -2 at 500 °C, resulting from the mixed electronic and ionic conductivity in the SDC electrolyte and thus reducing the fuel efficiency, can nonetheless help remove any carbon deposit and thereby ensure stable and coking-free operation of low temperature SOFCs in methanol fuels.

  15. Acidities of Water and Methanol in Aqueous Solution and DMSO

    ERIC Educational Resources Information Center

    Gao, Daqing

    2009-01-01

    The relative acidities of water and methanol have been a nagging issue. In gas phase, methanol is more acidic than water by 36.0 kJ/mol; however, in aqueous solution, the acidities of methanol and water are almost identical. The acidity of an acid in solution is determined by both the intrinsic gas-phase ionization Gibbs energy and the solvent…

  16. Acidities of Water and Methanol in Aqueous Solution and DMSO

    ERIC Educational Resources Information Center

    Gao, Daqing

    2009-01-01

    The relative acidities of water and methanol have been a nagging issue. In gas phase, methanol is more acidic than water by 36.0 kJ/mol; however, in aqueous solution, the acidities of methanol and water are almost identical. The acidity of an acid in solution is determined by both the intrinsic gas-phase ionization Gibbs energy and the solvent…

  17. Recent Advances in High-Performance Direct Methanol Fuel Cells

    NASA Technical Reports Server (NTRS)

    Narayanan, S. R.; Chun, W.; Valdez, T. I.; Jeffries-Nakamura, B.; Frank, H.; Surumpudi, S.; Halpert, G.; Kosek, J.; Cropley, C.; La Conti, A. B.; hide

    1996-01-01

    Direct methanol fuel cells for portable power applications have been advanced significantly under DARPA- and ARO-sponsored programs over the last five years. A liquid-feed, direct methanol fuel cell developed under these programs, employs a proton exchange membrane as electrolyte and operates on aqueous solutions of methanol with air or oxygen as the oxidant.

  18. Torsion-rotation intensities in methanol

    NASA Astrophysics Data System (ADS)

    Pearson, John

    Methanol exists in numerous kinds of astronomical objects featuring a wide range of local conditions. The light nature of the molecule coupled with the internal rotation of the methyl group with respect to the hydroxyl group results in a rich, strong spectrum that spans the entire far-infrared region. As a result, any modest size observational window will have a number of strong methanol transitions. This has made it the gas of choice for testing THz receivers and to extract the local physical conditions from observations covering small frequency windows. The latter has caused methanol to be dubbed the Swiss army knife of astrophysics. Methanol has been increasingly used in this capacity and will be used even more for subsequent investigations into the Herschel archive, and with SOFIA and ALMA. Interpreting physical conditions on the basis of a few methanol lines requires that the molecular data, line positions, intensities, and collision rates, be complete, consistent and accurate to a much higher level than previously required for astrophysics. The need for highly reliable data is even more critical for modeling the two classes of widespread maser action and many examples of optical pumping through the torsional bands. Observation of the torsional bands in the infrared will be a unique opportunity to directly connect JWST observations with those of Herschel, SOFIA, and ALMA. The theory for the intensities of torsion-rotation transitions in a molecule featuring a single internally rotating methyl group is well developed after 70 years of research. However, other than a recent very preliminary and not completely satisfactory investigation of a few CH3OH torsional bands, this theory has never been experimentally tested for any C3V internal rotor. More alarming is a set of recent intensity calibrated microwave measurements that showed deviations relative to calculations of up to 50% in some ground state rotational transitions commonly used by astronomers to extract

  19. Spontaneous Ejaculations Associated with Aripiprazole

    PubMed Central

    EĞİLMEZ, Oğuzhan; ÇELİK, Mustafa; KALENDEROĞLU, Aysun

    2016-01-01

    Sexual side effects are common with antipsychotic use. Spontaneous ejaculations without sexual arousal have been previously described with several typical and atypical antipsychotics. We report the case of a man who had spontaneous ejaculations after stopping risperidone and starting 30 mg/day aripiprazole. Spontaneous ejaculations ceased 3 days after decreasing the aripiprazole dose to 15 mg/day. He denied sexual fantasies or increased sexual desire during the period in which he had spontaneous ejaculations. The partial agonistic effect of aripiprazole on D2 receptors may have augmented the mesolimbic dopaminergic pathway, which was suppressed by risperidone, causing spontaneous ejaculations in this patient. Serotoninergic effects of aripiprazole should also be considered. This unusual side effect should be questioned, particularly in patients who recieve aripiprazole after D2-blocking antipsychotics; otherwise, this side effect may cause embarrassement and noncompliance. PMID:28360773

  20. Methane and methanol oxidation in supercritical water: Chemical kinetics and hydrothermal flame studies

    SciTech Connect

    Steeper, R.R.

    1996-01-01

    Supercritical water oxidation (SCWO) is an emerging technology for the treatment of wastes in the presence of a large concentration of water at conditions above water`s thermodynamic critical point. A high-pressure, optically accessible reaction cell was constructed to investigate the oxidation of methane and methanol in this environment. Experiments were conducted to examine both flame and non-flame oxidation regimes. Optical access enabled the use of normal and shadowgraphy video systems for visualization, and Raman spectroscopy for in situ measurement of species concentrations. Flame experiments were performed by steadily injecting pure oxygen into supercritical mixtures of water and methane or methanol at 270 bar and at temperatures from 390 to 510{degrees}C. The experiments mapped conditions leading to the spontaneous ignition of diffusion flames in supercritical water. Above 470{degrees}C, flames spontaneously ignite in mixtures containing only 6 mole% methane or methanol. This data is relevant to the design and operation of commercial SCWO processes that may be susceptible to inadvertent flame formation. Non-flame oxidation kinetics experiments measured rates of methane oxidation in supercritical water at 270 bar and at temperatures from 390 to 442{degrees}C. The initial methane concentration was nominally 0.15 gmol/L, a level representative of commercial SCWO processes. The observed methane concentration histories were fit to a one-step reaction rate expression indicating a reaction order close to two for methane and zero for oxygen. Experiments were also conducted with varying water concentrations (0 to 8 gmol/L) while temperature and initial reactant concentrations were held constant. The rate of methane oxidation rises steadily with water concentration up to about 5 gmol/L and then abruptly falls off at higher concentrations.

  1. Effect of pH on the spontaneous synthesis of palladium nanoparticles on reduced graphene oxide

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaorui; Ooki, Wataru; Kosaka, Yoshinori R.; Okonogi, Akinori; Marzun, Galina; Wagener, Philipp; Barcikowski, Stephan; Kondo, Takahiro; Nakamura, Junji

    2016-12-01

    Palladium (Pd) nanoparticles were spontaneously deposited on reduced graphene oxide (rGO) without any external reducing agents. The prepared Pd/rGO composites were then characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Spontaneous deposition occurred because of a redox reaction between the Pd precursor and rGO, which involved reduction of bivalent Pd to metallic Pd0 and oxidation of the sp2 carbon of rGO to oxygen-containing functional groups. The amount of Pd deposited on rGO varied with pH, and this was attributed to electrostatic interactions between the Pd precursor and rGO based on the results of zeta potential measurements. The importance of the redox reaction in the spontaneous deposition was demonstrated in the experiment with Zn, Ni, Cu, Ag, Pt, Pd, and Au.

  2. Platinum Nickel Nanowires as Methanol Oxidation Electrocatalysts

    DOE PAGES

    Alia, Shaun M.; Pylypenko, Svitlana; Neyerlin, Kenneth C.; ...

    2015-08-27

    We investigated platinum(Pt) nickel (Ni) nanowires (PtNiNWs) as methanol oxidation reaction (MOR) catalysts in rotating disk electrode (RDE) half-cells under acidic conditions. Pt-ruthenium (Ru) nanoparticles have long been the state of the art MOR catalyst for direct methanol fuel cells (DMFCs) where Ru provides oxophilic sites, lowering the potential for carbon monoxide oxidation and the MOR onset. Ru, however, is a precious metal that has long term durability concerns. Ni/Ni oxide species offer a potential to replace Ru in MOR electrocatalysis. PtNiNWs were investigated for MOR and oxygen annealing was investigated as a route to improve catalyst performance (mass activitymore » 65% greater) and stability to potential cycling. Our results presented show that PtNiNWs offer significant promise in the area, but also result in Ni ion leaching that is a concern requiring further evaluation in fuel cells.« less

  3. Platinum Nickel Nanowires as Methanol Oxidation Electrocatalysts

    SciTech Connect

    Alia, Shaun M.; Pylypenko, Svitlana; Neyerlin, Kenneth C.; Kocha, Shyam S.; Pivovar, Bryan S.

    2015-08-27

    We investigated platinum(Pt) nickel (Ni) nanowires (PtNiNWs) as methanol oxidation reaction (MOR) catalysts in rotating disk electrode (RDE) half-cells under acidic conditions. Pt-ruthenium (Ru) nanoparticles have long been the state of the art MOR catalyst for direct methanol fuel cells (DMFCs) where Ru provides oxophilic sites, lowering the potential for carbon monoxide oxidation and the MOR onset. Ru, however, is a precious metal that has long term durability concerns. Ni/Ni oxide species offer a potential to replace Ru in MOR electrocatalysis. PtNiNWs were investigated for MOR and oxygen annealing was investigated as a route to improve catalyst performance (mass activity 65% greater) and stability to potential cycling. Our results presented show that PtNiNWs offer significant promise in the area, but also result in Ni ion leaching that is a concern requiring further evaluation in fuel cells.

  4. Depolymerization of polyethylene terephthalate in supercritical methanol

    NASA Astrophysics Data System (ADS)

    Goto, Motonobu; Koyamoto, Hiroshi; Kodama, Akio; Hirose, Tsutomu; Nagaoka, Shoji

    2002-11-01

    The degradation of polyethylene terephthalate (PET) in supercritical methanol was investigated with the aim of developing a process for chemical recycling of waste plastics. A batch reactor was used at temperatures of 573-623 K under an estimated pressure of 20 MPa for a reaction time of 2-120 min. PET was decomposed to its monomers, dimethyl terephthalate and ethylene glycol, by methanolysis in supercritical methanol. The reaction products were analysed using size-exclusion chromatography, gas chromatography-mass spectrometry, and reversed-phase liquid chromatography. The molecular weight distribution of the products was obtained as a function of reaction time. The yields of monomer components of the decomposition products including by-products were measured. Continuous kinetics analysis was performed on the experimental data.

  5. Cyclo­linopeptide A methanol solvate

    PubMed Central

    Quail, J. Wilson; Shen, J.; Reaney, M. J. T.; Sammynaiken, R.

    2009-01-01

    Crystals of the title compound, C57H85N9O9·CH4O, the methanol solvate of a nine peptide polypeptide, cyclo-(Pro-Pro-Phe-Phe-Leu-Ile-Ile-Leu-Val), were obtained after separation of the cyclic peptide from flax oil. The cyclo­linopeptide A (CLP-A) mol­ecules are linked in chains along the a axis by N—H⋯O hydrogen bonds. Each methanol O atom is hydrogen bonded to one O atom and two N—H groups in the same CLP-A mol­ecule. There are a total of eight hydrogen bonds in each CLP-A–MeOH unit. PMID:21583600

  6. Stevioside methanol tetra­solvate

    PubMed Central

    Wu, Yunshan; Rodenburg, Douglas L.; Ibrahim, Mohamed A.; McChesney, James D.; Avery, Mitchell A.

    2013-01-01

    Stevioside is a naturally occurring diterpenoid glycoside in Stevia rebaudiana Bertoni. The title compound, C38H60O18·4CH3OH, crystallized as its methanol tetrasolvate. Stevioside consists of an aglycone steviol (a tetra­cyclic diterpene in which the four-fused-ring system consists of three six-membered rings and one five-membered ring) and a sugar part (three glucose units). A weak intra­molecular O—H⋯O hydrogen bond occurs. In the crystal, the methanol mol­ecules participate in a two-dimensional hydrogen-bonded network parallel to b axis with the sugars and together they form a hydrophilic tunnel which encloses the lipophilic part of the molecule. PMID:23476589

  7. Rapid detection of methanol in artisanal alcoholic beverages

    NASA Astrophysics Data System (ADS)

    de Goes, R. E.; Muller, M.; Fabris, J. L.

    2015-09-01

    In the industry of artisanal beverages, uncontrolled production processes may result in contaminated products with methanol, leading to risks for consumers. Owing to the similar odor of methanol and ethanol, as well as their common transparency, the distinction between them is a difficult task. Contamination may also occur deliberately due to the lower price of methanol when compared to ethanol. This paper describes a spectroscopic method for methanol detection in beverages based on Raman scattering and Principal Component Analysis. Associated with a refractometric assessment of the alcohol content, the method may be applied in field for a rapid detection of methanol presence.

  8. Compact Fuel-Cell System Would Consume Neat Methanol

    NASA Technical Reports Server (NTRS)

    Narayanan, Sekharipuram; Kindler, Andrew; Valdez, Thomas

    2007-01-01

    In a proposed direct methanol fuel-cell electric-power-generating system, the fuel cells would consume neat methanol, in contradistinction to the dilute aqueous methanol solutions consumed in prior direct methanol fuel-cell systems. The design concept of the proposed fuel-cell system takes advantage of (1) electro-osmotic drag and diffusion processes to manage the flows of hydrogen and water between the anode and the cathode and (2) evaporative cooling for regulating temperature. The design concept provides for supplying enough water to the anodes to enable the use of neat methanol while ensuring conservation of water for the whole fuel-cell system.

  9. Towards oil independence through renewable methanol chemistry.

    PubMed

    Olah, George A

    2013-01-02

    Recycling of CO(2) into methanol, dimethyl ether (DME), and derived fuels and materials is a feasible approach to address our carbon conundrum. It would free humankind from its dependence on fossil fuel while at the same time help mitigate the problems associated with excessive CO(2) emission. The energy needed for this carbon cycle can come from renewable sources (hydro, solar, wind) as well as atomic energy. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. The methanol industry`s missed opportunities

    SciTech Connect

    Stokes, C.A.

    1995-12-31

    Throughout its history the methanol industry has been backward in research and development and in industry cooperation on public image and regulatory matters. It has been extremely reticent as to the virtue of its product for new uses, especially for motor fuel. While this is perhaps understandable looking back, it is inexcusable looking forward. The industry needs to cooperate on a worldwide basis in research and market development, on the one hand, and in image-building and political influence, on the other, staying, of course, within the US and European and other regional antitrust regulations. Unless the industry develops the motor fuel market, and especially the exciting new approach through fuel cell operated EVs, to siphon off incremental capacity and keep plants running at 90% or more of capacity, it will continue to live in a price roller-coaster climate. A few low-cost producers will do reasonably well and the rest will just get along or drop out here and there along the way, as in the past. Having come so far from such a humble beginning, it is a shame not to realize the full potential that is clearly there: a potential to nearly double sales dollars without new plants and to produce from a plentiful resource, at least for the next half-century, all the methanol that can be imagined to be needed. Beyond that the industry can turn to renewable energy--the sun--via biomass growth, to make their product. In so doing, it can perhaps apply methanol as a plant growth stimulant, in effect making the product fully self-sustainable. The world needs to know what methanol can do to provide--economically and reliably--the things upon which a better life rests.

  11. Lightweight Stacks of Direct Methanol Fuel Cells

    NASA Technical Reports Server (NTRS)

    Narayanan, Sekharipuram; Valdez, Thomas

    2004-01-01

    An improved design concept for direct methanol fuel cells makes it possible to construct fuel-cell stacks that can weigh as little as one-third as much as do conventional bipolar fuel-cell stacks of equal power. The structural-support components of the improved cells and stacks can be made of relatively inexpensive plastics. Moreover, in comparison with conventional bipolar fuel-cell stacks, the improved fuel-cell stacks can be assembled, disassembled, and diagnosed for malfunctions more easily. These improvements are expected to bring portable direct methanol fuel cells and stacks closer to commercialization. In a conventional bipolar fuel-cell stack, the cells are interspersed with bipolar plates (also called biplates), which are structural components that serve to interconnect the cells and distribute the reactants (methanol and air). The cells and biplates are sandwiched between metal end plates. Usually, the stack is held together under pressure by tie rods that clamp the end plates. The bipolar stack configuration offers the advantage of very low internal electrical resistance. However, when the power output of a stack is only a few watts, the very low internal resistance of a bipolar stack is not absolutely necessary for keeping the internal power loss acceptably low.

  12. Liquid methanol under a static electric field

    SciTech Connect

    Cassone, Giuseppe; Giaquinta, Paolo V.; Saija, Franz; Saitta, A. Marco

    2015-02-07

    We report on an ab initio molecular dynamics study of liquid methanol under the effect of a static electric field. We found that the hydrogen-bond structure of methanol is more robust and persistent for field intensities below the molecular dissociation threshold whose value (≈0.31 V/Å) turns out to be moderately larger than the corresponding estimate obtained for liquid water. A sustained ionic current, with ohmic current-voltage behavior, flows in this material for field intensities above 0.36 V/Å, as is also the case of water, but the resulting ionic conductivity (≈0.40 S cm{sup −1}) is at least one order of magnitude lower than that of water, a circumstance that evidences a lower efficiency of proton transfer processes. We surmise that this study may be relevant for the understanding of the properties and functioning of technological materials which exploit ionic conduction, such as direct-methanol fuel cells and Nafion membranes.

  13. Methanol as A Tracer of Fundamental Constants

    NASA Astrophysics Data System (ADS)

    Levshakov, S. A.; Kozlov, M. G.; Reimers, D.

    2011-09-01

    The methanol molecule CH3OH has a complex microwave spectrum with a large number of very strong lines. This spectrum includes purely rotational transitions as well as transitions with contributions of the internal degree of freedom associated with the hindered rotation of the OH group. The latter takes place due to the tunneling of hydrogen through the potential barriers between three equivalent potential minima. Such transitions are highly sensitive to changes in the electron-to-proton mass ratio, μ = m e/m p, and have different responses to μ-variations. The highest sensitivity is found for the mixed rotation-tunneling transitions at low frequencies. Observing methanol lines provides more stringent limits on the hypothetical variation of μ than ammonia observation with the same velocity resolution. We show that the best-quality radio astronomical data on methanol maser lines constrain the variability of μ in the Milky Way at the level of |Δμ/μ| < 28 × 10-9 (1σ) which is in line with the previously obtained ammonia result, |Δμ/μ| < 29 × 10-9 (1σ). This estimate can be further improved if the rest frequencies of the CH3OH microwave lines will be measured more accurately.

  14. Class i Methanol Maser Conditions Near SNRS

    NASA Astrophysics Data System (ADS)

    McEwen, Bridget C.; Pihlström, Ylva M.; Sjouwerman, Loránt O.

    2015-06-01

    We present results from calculations of the physical conditions necessary for the occurrence of 36.169 (4-1-30 E), 44.070 (70-61 A^+), 84.521 (5-1-40 E), and 95.169 (80-71 A^+) GHz methanol (CH_3OH) maser emission lines near supernova remnants (SNRs), using the MOLPOP-CEP program. The calculations show that given a sufficient methanol abundance, methanol maser emission arises over a wide range of densities and temperatures, with optimal conditions at n˜ 10^4-10^6 cm-3 and T>60 K. The 36~GHz and 44~GHz transitions display more significant maser optical depths compared to the 84~GHz and 95~GHz transitions over the majority of physical conditions. It is also shown that line ratios are an important and applicable probe of the gas conditions. The line ratio changes are largely a result of the E-type transitions becoming quenched faster at increasing densities. The modeling results will be discussed using recent observations of CH_3OH masers near the SNRs G1.4-0.1, W28, and Sgr A East and used as a diagnostic tool to estimate densities and temperatures of the regions in which the CH_3OH masers are observed.

  15. Spontaneous Intracerebral Hemorrhage: Management

    PubMed Central

    Kim, Jun Yup; Bae, Hee-Joon

    2017-01-01

    Spontaneous non-traumatic intracerebral hemorrhage (ICH) remains a significant cause of mortality and morbidity throughout the world. To improve the devastating course of ICH, various clinical trials for medical and surgical interventions have been conducted in the last 10 years. Recent large-scale clinical trials have reported that early intensive blood pressure reduction can be a safe and feasible strategy for ICH, and have suggested a safe target range for systolic blood pressure. While new medical therapies associated with warfarin and non-vitamin K antagonist oral anticoagulants have been developed to treat ICH, recent trials have not been able to demonstrate the overall beneficial effects of surgical intervention on mortality and functional outcomes. However, some patients with ICH may benefit from surgical management in specific clinical contexts and/or at specific times. Furthermore, clinical trials for minimally invasive surgical evacuation methods are ongoing and may provide positive evidence. Upon understanding the current guidelines for the management of ICH, clinicians can administer appropriate treatment and attempt to improve the clinical outcome of ICH. The purpose of this review is to help in the decision-making of the medical and surgical management of ICH. PMID:28178413

  16. Spontaneous breaking of supersymmetry

    SciTech Connect

    Zumino, B.

    1981-12-01

    There has been recently a revival of interest in supersymmetric gauge theories, stimulated by the hope that supersymmetry might help in clarifying some of the questions which remain unanswered in the so called Grand Unified Theories and in particular the gauge hierarchy problem. In a Grand Unified Theory one has two widely different mass scales: the unification mass M approx. = 10/sup 15/GeV at which the unification group (e.g. SU(5)) breaks down to SU(3) x SU(2) x U(1) and the mass ..mu.. approx. = 100 GeV at which SU(2) x U(1) is broken down to the U(1) of electromagnetism. There is at present no theoretical understanding of the extreme smallness of the ratio ..mu../M of these two numbers. This is the gauge hierarchy problem. This lecture attempts to review the various mechanisms for spontaneous supersymmetry breaking in gauge theories. Most of the discussions are concerned with the tree approximation, but what is presently known about radiative correction is also reviewed.

  17. Supercritical methanol for polyethylene terephthalate depolymerization: Observation using simulator

    SciTech Connect

    Genta, Minoru; Iwaya, Tomoko; Sasaki, Mitsuru; Goto, Motonobu

    2007-07-01

    To apply PET depolymerization in supercritical methanol to commercial recycling, the benefits of supercritical methanol usage in PET depolymerization was investigated from the viewpoint of the reaction rate and energy demands. PET was depolymerized in a batch reactor at 573 K in supercritical methanol under 14.7 MPa and in vapor methanol under 0.98 MPa in our previous work. The main products of both reactions were the PET monomers of dimethyl terephthalate (DMT) and ethylene glycol (EG). The rate of PET depolymerization in supercritical methanol was faster than that of PET depolymerization in vapor methanol. This indicates supercritical fluid is beneficial in reducing reaction time without the use of a catalyst. We depicted the simple process flow of PET depolymerization in supercritical methanol and in vapor methanol, and by simulation evaluated the total heat demand of each process. In this simulation, bis-hydroxyethyl terephthalate (BHET) was used as a model component of PET. The total heat demand of PET depolymerization in supercritical methanol was 2.35 x 10{sup 6} kJ/kmol Produced-DMT. That of PET depolymerization in vapor methanol was 2.84 x 10{sup 6} kJ/kmol Produced-DMT. The smaller total heat demand of PET depolymerization in supercritical methanol clearly reveals the advantage of using supercritical fluid in terms of energy savings.

  18. Associated species in vaporized methanol-formaldehyde solutions

    SciTech Connect

    Silverman, D.C.; Freeman, J.J.

    1983-07-01

    Analysis of vaporized methanolic formaldehyde (50 mol % methanol) by gas chromatography revealed a sum of mole percents of formaldehyde, water, and methanol greater than 100%. This inconsistency was not found with vaporized solutions containing 1 or 10 mol % methanol. Direct evidence for an adduct of methanol and formaldehyde (CH/sub 3/OCH/sub 2/OH) in the vapor phase was found by use of infrared spectroscopy. The spectrum exhibited an absorption at 1140 cm/sup -1/ corresponding to a C-O-C stretch. Reasonable agreement was found between the C-O-C mole percent estimated from infrared spectroscopy, the increased amount of material detected by gas chromatography, and the estimated equilibrium mole percent of the adduct CH/sub 3/OCH/sub 2/OH. These results confirm that in completely vaporized methanolic formaldehyde at 373 to 423 K, one type of adduct predominates. It contains one molecule each of formaldehyde and methanol.

  19. Neurological Complications Resulting from Non-Oral Occupational Methanol Poisoning.

    PubMed

    Choi, Ji Hyun; Lee, Seung Keun; Gil, Young Eun; Ryu, Jia; Jung-Choi, Kyunghee; Kim, Hyunjoo; Choi, Jun Young; Park, Sun Ah; Lee, Hyang Woon; Yun, Ji Young

    2017-02-01

    Methanol poisoning results in neurological complications including visual disturbances, bilateral putaminal hemorrhagic necrosis, parkinsonism, cerebral edema, coma, or seizures. Almost all reported cases of methanol poisoning are caused by oral ingestion of methanol. However, recently there was an outbreak of methanol poisoning via non-oral exposure that resulted in severe neurological complications to a few workers at industrial sites in Korea. We present 3 patients who had severe neurological complications resulting from non-oral occupational methanol poisoning. Even though initial metabolic acidosis and mental changes were improved with hemodialysis, all of the 3 patients presented optic atrophy and ataxia or parkinsonism as neurological complications resulting from methanol poisoning. In order to manage it adequately, as well as to prevent it, physicians should recognize that methanol poisoning by non-oral exposure can cause neurologic complications.

  20. A New 95 GHz Methanol Maser Catalog. I. Data

    NASA Astrophysics Data System (ADS)

    Yang, Wenjin; Xu, Ye; Chen, Xi; Ellingsen, Simon P.; Lu, Dengrong; Ju, Binggang; Li, Yingjie

    2017-08-01

    The Purple Mountain Observatory 13.7 m radio telescope has been used to search for 95 GHz (80–71A+) class I methanol masers toward 1020 Bolocam Galactic Plane Survey (BGPS) sources, leading to 213 detections. We have compared the line width of the methanol and HCO+ thermal emission in all of the methanol detections, and on that basis, we find that 205 of the 213 detections are very likely to be masers. This corresponds to an overall detection rate of 95 GHz methanol masers toward our BGPS sample of 20%. Of the 205 detected masers, 144 (70%) are new discoveries. Combining our results with those of previous 95 GHz methanol maser searches, a total of 481 95 GHz methanol masers are now known. We have compiled a catalog listing the locations and properties of all known 95 GHz methanol masers.

  1. Neurological Complications Resulting from Non-Oral Occupational Methanol Poisoning

    PubMed Central

    Lee, Seung Keun; Gil, Young-Eun; Kim, Hyunjoo; Choi, Jun Young

    2017-01-01

    Methanol poisoning results in neurological complications including visual disturbances, bilateral putaminal hemorrhagic necrosis, parkinsonism, cerebral edema, coma, or seizures. Almost all reported cases of methanol poisoning are caused by oral ingestion of methanol. However, recently there was an outbreak of methanol poisoning via non-oral exposure that resulted in severe neurological complications to a few workers at industrial sites in Korea. We present 3 patients who had severe neurological complications resulting from non-oral occupational methanol poisoning. Even though initial metabolic acidosis and mental changes were improved with hemodialysis, all of the 3 patients presented optic atrophy and ataxia or parkinsonism as neurological complications resulting from methanol poisoning. In order to manage it adequately, as well as to prevent it, physicians should recognize that methanol poisoning by non-oral exposure can cause neurologic complications. PMID:28049252

  2. Anti-hypertensive effect of the Dongchunghacho, Isaria sinclairii, in the spontaneously hypertensive rats.

    PubMed

    Ahn, Mi Young; Jung, Yi Sook; Jee, Sang Deok; Kim, Chan Shik; Lee, Su Hwan; Moon, Chang Hyun; Cho, Sung Ig; Lee, Byung Mu; Ryu, Kang Sun

    2007-04-01

    The present study examined the effect of the methanol extract of Isaria sinclairii, a kind of Donchunghacho (Tochukaso), on blood pressure in spontaneously hypertensive rats (SHR). Blood pressure and heart rate were measured after treatment with the methanol extract of I. sinclairii by the indirect tail-cuff method and the direct in vivo model. Starting at 12 weeks of age, male SHR were treated with the extracts for 2 or 4 weeks. We found that, when compared to untreated control SHR, oral treatment with I. sinclairii methanol extract (30 mg/kg/day) remarkably decreased systolic blood pressure from 200 to 112 mmHg and decreased diastolic blood pressure from 114 to 88 mmHg. Furthermore, efficacy of methanol extract of I. sinclairii was superior to captopril (30 mg/kg/mL, positive control), an angiotensin-converting enzyme inhibitor, with a lowering effect that dropped systolic blood pressure from 201 to 130 mmHg and diastolic blood pressure from 102 to 92 mmHg. However, in normal Wistar Kyoto rats, I. sinclairii methanol extract did not significantly change the normal blood pressure, suggesting that this type of Dongchunghacho has a selective effect against hypertension. Therefore, methanol extract of I. sinclairii may be used as an anti-hypertensive food/agent. Furthermore, this extract also has multiple actions such as No production in endothelial cells, inhibiting thrombin-induced blood coagulation by thrombin and mildly decreasing in prostaglandin E2 levels in cultured macrophage cells, all of which might contribute to protection against atherogenesis and thrombus formation. HPLC and MS analysis of methanol extract of I. sinclairii revealed the presence of adenosine.

  3. Novel Diamond Films Synthesis Strategy: Methanol and Argon Atmosphere by Microwave Plasma CVD Method Without Hydrogen.

    PubMed

    Yang, Li; Jiang, Caiyi; Guo, Shenghui; Zhang, Libo; Gao, Jiyun; Peng, Jinhui; Hu, Tu; Wang, Liang

    2016-12-01

    Diamond thin films are grown on silicon substrates by only using methanol and argon mixtures in microwave plasma chemical vapor deposition (MPCVD) reactor. It is worth mentioning that the novel strategy makes the synthesis reaction works smoothly without hydrogen atmosphere, and the substrates temperature is only 500 °C. The evidence of surface morphology and thickness under different time is obtained by characterizing the samples using scanning electron microscopy (SEM). X-ray diffractometer (XRD) spectrum reveals that the preferential orientation of (111) plane sample is obtained. The Raman spectra indicate that the dominant component of all the samples is a diamond. Moreover, the diamond phase content of the targeted films was quantitatively analyzed by X-ray photoelectron spectroscopy (XPS) method, and the surface roughness of diamond films was investigated by atomic force microscope (AFM). Meanwhile, the possible synthesis mechanism of the diamond films in methanol- and argon-mixed atmosphere was discussed.

  4. Novel Diamond Films Synthesis Strategy: Methanol and Argon Atmosphere by Microwave Plasma CVD Method Without Hydrogen

    NASA Astrophysics Data System (ADS)

    Yang, Li; Jiang, Caiyi; Guo, Shenghui; Zhang, Libo; Gao, Jiyun; Peng, Jinhui; Hu, Tu; Wang, Liang

    2016-09-01

    Diamond thin films are grown on silicon substrates by only using methanol and argon mixtures in microwave plasma chemical vapor deposition (MPCVD) reactor. It is worth mentioning that the novel strategy makes the synthesis reaction works smoothly without hydrogen atmosphere, and the substrates temperature is only 500 °C. The evidence of surface morphology and thickness under different time is obtained by characterizing the samples using scanning electron microscopy (SEM). X-ray diffractometer (XRD) spectrum reveals that the preferential orientation of (111) plane sample is obtained. The Raman spectra indicate that the dominant component of all the samples is a diamond. Moreover, the diamond phase content of the targeted films was quantitatively analyzed by X-ray photoelectron spectroscopy (XPS) method, and the surface roughness of diamond films was investigated by atomic force microscope (AFM). Meanwhile, the possible synthesis mechanism of the diamond films in methanol- and argon-mixed atmosphere was discussed.

  5. High performance methanol-oxygen fuel cell with hollow fiber electrode

    NASA Technical Reports Server (NTRS)

    Lawson, Daniel D. (Inventor); Ingham, John D. (Inventor)

    1983-01-01

    A methanol/air-oxygen fuel cell including an electrode formed by open-ended ion-exchange hollow fibers having a layer of catalyst deposited on the inner surface thereof and a first current collector in contact with the catalyst layer. A second current collector external of said fibers is provided which is immersed along with the hollow fiber electrode in an aqueous electrolyte body. Upon passage of air or oxygen through the hollow fiber electrode and introduction of methanol into the aqueous electrolyte, a steady current output is obtained. Two embodiments of the fuel cell are disclosed. In the first embodiment the second metal electrode is displaced away from the hollow fiber in the electrolyte body while in the second embodiment a spiral-wrap electrode is provided about the outer surface of the hollow fiber electrode.

  6. Spontaneous combustion of shale spoils at a sanitary landfill.

    PubMed

    Hudak, Paul F

    2002-01-01

    Shale deposits excavated from the Upper Cretaceous, Eagle Ford Formation for a sanitary landfill near Dallas, Texas spontaneously combusted. The shale is dark gray in color, with 3-4% fractional organic carbon, and no lignite seams. Gradual sifting and segregation of fine particles, having high surface area per unit volume, along with moisture trapped in the pile as it accumulated led to spontaneous combustion. Hot summer temperatures compounded the problem by heating the pile and preventing heat from efficiently venting to the atmosphere. Maximum temperatures exceeded 960 degrees F (516 degrees C) at several hot spots located approximately 4 m beneath the pile surface. The ongoing combustion problem, which has lasted for approximately 1 year, eventually will be extinguished by spreading the deposits in thin layers, and compacting them to reduce air circulation and segregation of fines.

  7. Spontaneous baryogenesis without baryon isocurvature

    NASA Astrophysics Data System (ADS)

    De Simone, Andrea; Kobayashi, Takeshi

    2017-02-01

    We propose a new class of spontaneous baryogenesis models that does not produce baryon isocurvature perturbations. The baryon chemical potential in these models is independent of the field value of the baryon-generating scalar, hence the scalar field fluctuations are blocked from propagating into the baryon isocurvature. We demonstrate this mechanism in simple examples where spontaneous baryogenesis is driven by a non-canonical scalar field. The suppression of the baryon isocurvature allows spontaneous baryogenesis to be compatible even with high-scale inflation.

  8. Efficient Ceria-Platinum Inverse Catalyst for Partial Oxidation of Methanol.

    PubMed

    Ostroverkh, Anna; Johánek, Viktor; Kúš, Peter; Šedivá, Romana; Matolín, Vladimír

    2016-06-28

    Ceria-platinum-based bilayered thin films deposited by magnetron sputtering were developed and tested in regard to their catalytic activity for methanol oxidation by employing a temperature-programmed reaction (TPR) technique. The composition and structure of the samples were characterized by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Both conventional (oxide-supported metal nanoparticles [NPs]) and inverse configurations (metal with oxide overlayer) were analyzed to uncover the structural dependence of activity and selectivity of these catalysts with respect to different pathways of methanol oxidation. We clearly demonstrate that the amount of cerium oxide (ceria) loading has a profound influence on methanol oxidation reaction characteristics. Adding a noncontinuous adlayer of ceria greatly enhances the catalytic performance of platinum (Pt) in favor of partial oxidation of methanol (POM), gaining an order of magnitude in the absolute yield of hydrogen. Moreover, the undesired by-production of carbon monoxide (CO) is strongly suppressed, making the ceria-platinum inverse catalyst a great candidate for clean hydrogen production. It is suggested that the methanol oxidation process is facilitated by the synergistic effect between both components of the inverse catalyst (involving oxygen from ceria and providing a reaction site on the adjacent Pt surface) as well as by the fact that the ability of ceria to exchange oxygen (i.e., to alter the oxidation state of Ce between 3+ and 4+) during the reaction is inversely proportional to its thickness. The increased redox capability of the discontinuous ceria adlayer shifts the preferred reaction pathway from dehydrogenation of hydroxymethyl intermediate to CO in favor of its oxidation to formate.

  9. Discovery of Methanol in a Planetary Birthplace

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-05-01

    Data from the Atacama Large Millimeter/submillimeter Array (ALMA) has recently revealed the first detection of gas-phase methanol, a derivative of methane, in a protoplanetary disk. This milestone discovery is an important step in understanding the conditions for planet formation that can lead to life-supporting planets like Earth.Planetary ChemistryOne major goal in the study of exoplanets is to find planets that orbit in their host stars habitable zones, a measure that determines whether the planet receives the right amount of sunlight to support liquid water. But theres another crucial element in the formation of a life-supporting planet: chemistry.To understand the chemistry of newly born planets, we need to study protoplanetary disks because its from these that young planets form. The elements and molecules contained in these dusty disks are what initially make up the atmospheres of planets forming within the disks.The Atacama Large Millimeter/submillimeter Array under the southern sky. [ESO/B. Tafreshi]The Hunt for ComplexityThe detection of complex molecules in protoplanetary disks is an important milestone, because complex molecules are necessary to build the correct chemistry to support life. Unfortunately, detecting these molecules is very difficult, requiring observations with both high spatial resolution and high sensitivity. Thus far, though weve observed elements and simple molecules in protoplanetary disks, detections of complex molecules have been elusive with only one success before now.Luckily, we now have an observatory up to the challenge! ALMAs unprecedented spatial resolution and sensitivity has recently allowed a team of scientists led by Catherine Walsh (Leiden University) to observe gas-phase methanol in a protoplanetary disk for the first time. This detection was made in the disk around the young star TW Hya, and it represents one of the largest molecules that has ever been observed in a disk to date.Locating IcesThe model (purple line

  10. Inhalation toxicity study of methanol, toluene, and methanol/toluene mixtures in rats: effects of 28-day exposure.

    PubMed

    Poon, R; Chu, I; Bjarnason, S; Potvin, M; Vincent, R; Miller, R B; Valli, V E

    1994-01-01

    The inhalation toxicity of methanol and toluene was investigated in rats. Young Sprague Dawley rats of both sexes were exposed to vapors of methanol (300 ppm, 3000 ppm), toluene (30 ppm, 300 ppm) or methanol/toluene (300/30 ppm, 300/300 ppm, 3000/30 ppm, and 3000/300 ppm) six hrs per day, five days/week for four weeks. Control animals inhaled air only. Increased serum alkaline phosphatase activity was observed in males exposed to high-dose toluene, and decreased creatinine was noted in the group exposed to high-dose methanol/toluene. The thyroid gland in females appeared to be a target organ for inhaled methanol, toluene, and methanol/toluene, although the changes were confined to a mild, and occasionally moderate, reduction in follicle size. Histopathological changes of the nasal passages, consisting of subepithelial nonsuppurative inflammation, occurred in higher incidences in rats exposed to methanol/toluene than in those exposed to the individual vapors. Inhalation of methanol, toluene, or methanol/toluene produced no changes in liver weights, hepatic mixed-function oxidases, or serum aspartate transaminase activities, and onlly minimal changes in liver histopathology. The only liver changes were decreased liver weight and increased cytoplasmic density of the periportal areas in females exposed to high-dose methanol/toluene. These data indicated that exposure to methanol, toluene, or a mixture of both produced mild biochemical effects and histological changes in the thyroid and nasal passage. No apparent interactive effects were observed.

  11. Electrochemical oxidation of methanol on Pt nanoparticles composited MnO 2 nanowire arrayed electrode

    NASA Astrophysics Data System (ADS)

    Zhao, Guang-Yu; Li, Hu-Lin

    2008-03-01

    By use of the membrane-template synthesis route, MnO 2 nanowire arrayed electrodes are successfully synthesized by means of the anodic deposition technique. The Pt nanoparticles composited MnO 2 nanowire arrayed electrodes (PME) are obtained through depositing Pt on MnO 2 nanowire arrayed electrode by cathode deposition technique. For comparison of electrochemical performance, Pt nanowire arrayed electrodes which have the same amount of Pt with PME are also prepared. The electro-oxidation of methanol on PME and Pt nanowire arrayed electrodes is investigated at room temperature by cyclic voltammetry, which show that about 110 mV decreased overpotential and 2.1-fold enhanced votammetric current are achieved on PME. The chronoamperometry result demonstrates that the resistance to carbon monoxide for PME is improved.

  12. A novel process for methanol synthesis. [Concurrent sythesis of methly formate and methanol

    SciTech Connect

    Tierney, J.W.; Wender, I.

    1992-01-01

    A bench-scale reactor is being used to conduct studies of the conversion of synthesis gas to methanol (MeOH) by a novel process. In previous reports, we provided evidence for a two-step reaction in series, the carbonylation reaction taking place mainly in a non-equilibrium region in the vicinity of the copper chromite surface, and the hydrogenolysis reaction taking place on the surface of the copper chromite. Interaction between the two catalysts enhances the rate of methanol formation. In this quarter, we investigated the effect of pore diffusion on reaction rate and obtained an expression for the rate of reaction for the methanol/methyl formate concurrent synthesis.

  13. Spontaneous emphysema of the neck.

    PubMed

    El-Ghazali, A M

    1983-04-01

    A case of spontaneous emphysema in the neck in a 17-year-old male was reported. Pathogenesis and management are discussed. Although it is a benign and self-limiting condition, it may carry a potential for serious complications.

  14. Methanol observation of IRAS 19312+1950: A possible new type of class I methanol maser

    NASA Astrophysics Data System (ADS)

    Nakashima, Jun-ichi; Sobolev, Andrej M.; Salii, Svetlana V.; Zhang, Yong; Yung, Bosco H. K.; Deguchi, Shuji

    2015-10-01

    We report the result of a systematic methanol observation toward IRAS 19312+1950. The properties of the SiO, H2O, and OH masers of this object are consistent with those of mass-losing evolved stars, but some other properties are difficult to explain in the standard scheme of stellar evolution in its late stage. Interestingly, a tentative detection of radio methanol lines was suggested toward this object by a previous observation. To date, there are no confirmed detections of methanol emission towards evolved stars, so investigation of this possible detection is important to better understand the circumstellar physical/chemical environment of IRAS 19312+1950. In this study, we systematically observed multiple methanol lines of IRAS 19312+1950 in the λ = 3 mm, 7 mm, and 13 mm bands, and detected six lines including four thermal lines and two class I maser lines. We derived basic physical parameters, including kinetic temperature and relative abundances, by fitting a radiative transfer model. According to the derived excitation temperature and line profiles, a spherically expanding outflow lying at the center of the nebulosity is excluded from the possibilities for methanol emission regions. The detection of class I methanol maser emission suggests that a shock region is involved in the system of IRAS 19312+1950. If the central star of IRAS 19312+1950 is an evolved star as suggested in the past, the class I maser detected in the present observation is the first case detected in an interaction region between an evolved star outflow and ambient molecular gas.

  15. Biogenic methanol and its impacts on tropospheric oxidants

    NASA Astrophysics Data System (ADS)

    Tie, Xuexi; Guenther, Alex; Holland, Elisabeth

    2003-09-01

    We use a global chemical transport model (MOZART-2) to estimate the effects of surface emissions of methanol on tropospheric oxidants. The importance of methanol in tropospheric chemistry is two fold. First, methanol has a relatively large surface emission with an estimated global emission of 70 to 350 Tg methanol/year. The estimated methanol flux is comparable to other major hydrocarbon surface emissions such as isoprene and total monoterpenes, but the chemical lifetime of methanol is several days (in the boundary layer) to a few weeks (in the upper troposphere), which is much longer than the chemical lifetime of isoprene or monoterpenes (For example, the chemical lifetime of isoprene is about 2 hours). With a surface emission of 104 to 312 Tg methanol/year (encompasses estimated uncertainty in methanol emissions), the calculation shows that on average, the inclusion of methanol emission produces approximately 1-2% increase in O3, 1-3% decrease in OH, 3-5% increase in HO2, and 3-9% increase in CH2O globally. The maximum perturbation to the oxidants occurs in the tropical upper troposphere. However, the uncertainty associated with current methanol emission estimates produces significantly different model predictions of tropospheric oxidant distributions.

  16. Spontaneous Activity in Crustacean Neurons

    PubMed Central

    Preston, James B.; Kennedy, Donald

    1962-01-01

    Single units which discharged with regular spontaneous rhythms without intentional stimulation were observed in the ventral nerve cord by intracellular recording close to the sixth abdominal ganglion. These units were divided into two groups: group A units in which interspike intervals varied less than 10 msec.; group B units in which interspike intervals varied within a range of 10 to 30 msec. Group A units maintained "constant" interspike intervals and could not be discharged by sensory inputs, while the majority of group B units could be discharged by appropriate sensory nerve stimulation. Both group A and B units discharged to direct stimulation when the stimulating and recording electrodes were placed in the same ganglionic intersegment, and directly evoked single spikes reset the spontaneous rhythm. In group B units, presynaptic volleys reset the spontaneous rhythm of some units; but in others, synaptically evoked spikes were interpolated within the spontaneous rhythm without resetting. The phenomenon of enhancement could also be demonstrated in spontaneously active units as a result of repetitive stimulation. It is concluded that endogenous pacemaker activity is responsible for much of the regular spontaneous firing observed in crayfish central neurons, and that interaction of evoked responses with such pacemaker sites can produce a variety of effects dependent upon the anatomical relationships between pacemaker and synaptic regions. PMID:14488667

  17. Thermodynamics and Spontaneity

    NASA Astrophysics Data System (ADS)

    Ochs, Raymond S.

    1996-10-01

    Despite the importance of thermodynamics as the foundation of chemistry, most students emerge from introductory courses with only a dim understanding of this subject. Generally students recognize that the information is significant, yet do not assimilate it into later studies, especially in applied fields such as biology and biochemistry. A clear sense of the problem is reflected in a number of other contributions to this Journal (e.g., 1 - 6). Most (1 - 4, 6) recommend increased rigor in derivation of equations. This may appeal to students in advanced courses in chemical thermodynamics, but not to most. A few other suggestions are to introduce the subject earlier in general chemistry courses (2) or to provide innovative ways to visualize reaction changes (3). I suggest that the problem lies at another level entirely: the meanings of the terms are not clear. Recently, MacNeal (7) introduced the concept of mathsemantics, the joining of mathematics with a deep understanding of the sense (semantics) in which it operates. For example, the author argues that not only can we add apples and oranges (yielding total fruit), but that anything less than such a synthesis is trivial. Mathematics is hard, not because of the actual mathematical part of the problem but because of the semantics. As discussed thoroughly by Weinburg (8), the very names we affix to ideas dominate how we think about them. A similar reorientation would benefit chemical education. By way of example, the word "spontaneous" is widely used in thermodynamics, presumably because the word is familiar and assists understanding of this subject. In the following, I will provide evidence that this word has contributed more to the obfuscation of chemical ideas than it has helped elucidate them. Literature Cited 1. Redlich, O. J. Chem. Educ. 1975, 52, 374 - 376. 2. Bergquist, W.; Heikkinen, H. J. Chem. Educ. 1990, 67, 1000 - 1003. 3. Macomber, R. S. J. Chem. Educ. 1994, 71, 311 - 312. 4. Sanchez, K. S.; Vergenz, R

  18. Methanol May Function as a Cross-Kingdom Signal

    PubMed Central

    Dorokhov, Yuri L.; Komarova, Tatiana V.; Petrunia, Igor V.; Kosorukov, Vyacheslav S.; Zinovkin, Roman A.; Shindyapina, Anastasia V.; Frolova, Olga Y.; Gleba, Yuri Y.

    2012-01-01

    Recently, we demonstrated that leaf wounding results in the synthesis of pectin methylesterase (PME), which causes the plant to release methanol into the air. Methanol emitted by a wounded plant increases the accumulation of methanol-inducible gene mRNA and enhances antibacterial resistance as well as cell-to-cell communication, which facilitates virus spreading in neighboring plants. We concluded that methanol is a signaling molecule involved in within-plant and plant-to-plant communication. Methanol is considered to be a poison in humans because of the alcohol dehydrogenase (ADH)-mediated conversion of methanol into toxic formaldehyde. However, recent data showed that methanol is a natural compound in normal, healthy humans. These data call into question whether human methanol is a metabolic waste product or whether methanol has specific function in humans. Here, to reveal human methanol-responsive genes (MRGs), we used suppression subtractive hybridization cDNA libraries of HeLa cells lacking ADH and exposed to methanol. This design allowed us to exclude genes involved in formaldehyde and formic acid detoxification from our analysis. We identified MRGs and revealed a correlation between increases in methanol content in the plasma and changes in human leukocyte MRG mRNA levels after fresh salad consumption by volunteers. Subsequently, we showed that the methanol generated by the pectin/PME complex in the gastrointestinal tract of mice induces the up- and downregulation of brain MRG mRNA. We used an adapted Y-maze to measure the locomotor behavior of the mice while breathing wounded plant vapors in two-choice assays. We showed that mice prefer the odor of methanol to other plant volatiles and that methanol changed MRG mRNA accumulation in the mouse brain. We hypothesize that the methanol emitted by wounded plants may have a role in plant-animal signaling. The known positive effect of plant food intake on human health suggests a role for physiological methanol in

  19. Direct methanol feed fuel cell and system

    NASA Technical Reports Server (NTRS)

    Surampudi, Subbarao (Inventor); Frank, Harvey A. (Inventor); Narayanan, Sekharipuram R. (Inventor); Chun, William (Inventor); Jeffries-Nakamura, Barbara (Inventor); Kindler, Andrew (Inventor); Halpert, Gerald (Inventor)

    2009-01-01

    Improvements to non acid methanol fuel cells include new formulations for materials. The platinum and ruthenium are more exactly mixed together. Different materials are substituted for these materials. The backing material for the fuel cell electrode is specially treated to improve its characteristics. A special sputtered electrode is formed which is extremely porous. The fuel cell system also comprises a fuel supplying part including a meter which meters an amount of fuel which is used by the fuel cell, and controls the supply of fuel based on said metering.

  20. A novel process for manufacture of methanol

    SciTech Connect

    Tierney, J.W.; Wender, I.

    1990-01-01

    A bench-scale reactor is being used to conduct studies of the conversion of synthesis gas to methanol by a novel process. During the last quarter, the effect of potassium methoxide and Cu-chromite loading on the MeOH formation rate was investigated. The rate obtained with Cu-chromite was compared to that using Cu-ZnO as catalyst. Work also continued on the modification of the experimental equipment to permit on-line monitoring of liquid and gas compositions.

  1. Single Shot Hugoniots of Toluene and Methanol

    NASA Astrophysics Data System (ADS)

    Bolme, C. A.; Eakins, D. E.; Funk, D. J.; McGrane, S. D.; Moore, D. S.; Whitley, V. H.

    2009-12-01

    Ultrafast dynamic ellipsometry was used to acquire shock and particle velocities and shocked refractive indices for toluene and methanol. The liquids were driven with a shock wave that was approximately 300 ps in duration, and the data for each was acquired in a single laser shot by utilizing the Gaussian spatial profile of the drive laser beam to create a range of pressures in the samples. The Hugoniot data match well with previous shock data and with Woolfolk's "universal liquid Hugoniot." The shocked refractive indices of both liquids deviate from the Gladstone-Dale relation, the value expected exclusively from a change in density.

  2. Improved Direct Methanol Fuel Cell Stack

    SciTech Connect

    Wilson, Mahlon S.; Ramsey, John C.

    2005-03-08

    A stack of direct methanol fuel cells exhibiting a circular footprint. A cathode and anode manifold, tie-bolt penetrations and tie-bolts are located within the circular footprint. Each fuel cell uses two graphite-based plates. One plate includes a cathode active area that is defined by serpentine channels connecting the inlet and outlet cathode manifold. The other plate includes an anode active area defined by serpentine channels connecting the inlet and outlet of the anode manifold, where the serpentine channels of the anode are orthogonal to the serpentine channels of the cathode. Located between the two plates is the fuel cell active region.

  3. The Relationship among Spontaneity, Impulsivity, and Creativity

    ERIC Educational Resources Information Center

    Kipper, David A.; Green, Doreen J.; Prorak, Amanda

    2010-01-01

    The present study was designed to investigate two characteristics of spontaneity, its relationship to creativity and to impulsivity. We hypothesized a positive relationship between spontaneity and creativity, consistent with Moreno, 1953 "canon of spontaneity-creativity." We also predicted a negative relationship between spontaneity and…

  4. Thermodynamic properties of direct methanol polymer electrolyte fuel cell

    NASA Astrophysics Data System (ADS)

    Seong, Ji Yun; Bae, Young Chan; Sun, Yang Kook

    A new semi-empirical model is established to describe the cell voltage of a direct methanol fuel cell (DMFC) as a function of current density. The model equation is validated experimental data over a wide range of a methanol concentration and temperatures. A number of existing models are semi-empirical. They, however, have a serious mathematical defect. When the current density, j, becomes zero, the equation should reduce to the open circuit voltage, E0. These models, however, do not meet the mathematical boundary condition. The proposed model focuses on very unfavorable conditions for the cell operation, i.e. low methanol solution concentrations and relatively low cell temperatures. A newly developed semi-empirical equation with reasonable boundary conditions includes the methanol crossover effect that plays a major role in determining the cell voltage of DMFC. Also, it contains methanol activity based on thermodynamic functions to represent methanol crossover effect.

  5. Methanol as an alternative fuel: Economic and health effects

    SciTech Connect

    Yuecel, M.K. )

    1991-09-01

    Switching from gasoline to methanol fuels has important economic and health effects. Replacing gasoline with methanol will affect oil markets by lowering the demand for oil and thus lowering oil prices. Increased demand for the natural gas feedstock will increase natural gas prices. Because methanol is more costly than gasoline, fuel prices will also increase. On the other hand, methanol use will reduce ozone pollution and some of the health risks associated with gasoline. Considering all three markets affected by the phasing-out of gasoline, the switch to methanol results in net gains. The health benefits from lower pollution and the lives saved from the switch from gasoline to methanol are in addition to these gains. Overall, the benefits of the policy far outweigh the costs. However, the gains in the oil market, arising from the US monopsony power in the world oil market, can be captured by other, more efficient policies. 21 refs., 2 figs., 3 tabs.

  6. World methanol situation poses challenge in process design

    SciTech Connect

    Haggin, J.

    1984-07-16

    A review is presented of the technology and economics of methanol production processes. Synthesis gas production based on methane or coal are compared. Since methane-based synthesis gas is hydrogen rich and coal-based synthesis gas is carbon rich, the combination of both processes, as suggested by the M.W. Kellogg Co., should be economically attractive. A liquid-phase synthesis in the developmental stages and two reactor configurations under consideration for its use are discussed. The Wentworth system of catalytic processing, a Lurgi process using coal and methane for methanol, a Lurgi process for utilizing methanol in a variation of the Mobil methanol-to-gasoline process, and another Lurgi process to produce a methanol fuel mixture for direct use as a motor fuel, consisting of methanol and oxygenates, are also discussed.

  7. Pressure Effects on Combustion of Methanol and Methanol-Docecanol Droplets

    NASA Technical Reports Server (NTRS)

    Okai, K.; Ono, Y.; Muriue, O.; Tsue, M.; Kono, M.; Sato, J.; Dietrich, D. L.; Williams, F. A.

    1999-01-01

    The objective of this research is to improve understanding of the combustion of binary fuel mixtures in the vicinity of the critical point. Fiber-supported single droplets and two-droplet arrays of methanol and of mixtures of methanol and 1-dodecanol, initially 0.9 mm in diameter, were burned in room-temperature air at pressures from 0.1 MPa to 9.0 MPa in the NASA Lewis 2.2-second drop tower. The work is a continuation of a collaborative Japan-US research effort designed to increase knowledge of high-pressure combustion of fuel sprays, relevant to application in propulsive and power-production devices such as Diesel engines. Some previous publications from this cooperative program may be cited. All of the previous experiments concerned alkanes and alkane mixtures. The new research reported here addresses alcohols and alcohol mixtures, to ascertain the degree to which previous results for alkanes extend to alcohols. There have been many previous experimental studies of methanol droplet combustion and a few of alcohol mixtures, but not at the high pressures of interest here. There is some experimental information on methanol droplet combustion at elevated pressure but none on the alcohol mixtures extending to critical pressures, as in the present study.

  8. Pressure Effects on Combustion of Methanol and Methanol-Docecanol Droplets

    NASA Technical Reports Server (NTRS)

    Okai, K.; Ono, Y.; Muriue, O.; Tsue, M.; Kono, M.; Sato, J.; Dietrich, D. L.; Williams, F. A.

    1999-01-01

    The objective of this research is to improve understanding of the combustion of binary fuel mixtures in the vicinity of the critical point. Fiber-supported single droplets and two-droplet arrays of methanol and of mixtures of methanol and 1-dodecanol, initially 0.9 mm in diameter, were burned in room-temperature air at pressures from 0.1 MPa to 9.0 MPa in the NASA Lewis 2.2-second drop tower. The work is a continuation of a collaborative Japan-US research effort designed to increase knowledge of high-pressure combustion of fuel sprays, relevant to application in propulsive and power-production devices such as Diesel engines. Some previous publications from this cooperative program may be cited. All of the previous experiments concerned alkanes and alkane mixtures. The new research reported here addresses alcohols and alcohol mixtures, to ascertain the degree to which previous results for alkanes extend to alcohols. There have been many previous experimental studies of methanol droplet combustion and a few of alcohol mixtures, but not at the high pressures of interest here. There is some experimental information on methanol droplet combustion at elevated pressure but none on the alcohol mixtures extending to critical pressures, as in the present study.

  9. Application Of Metal Coated Carbon Nanotubes To Direct Methanol Fuel Cells And For The Formation Of Nanowires

    NASA Astrophysics Data System (ADS)

    Frackowiak, E.; Lota, G.; Lota, K.; Béguin, F.

    2004-09-01

    Homogeneously distributed particles of Pt, Ru or their alloys were electrochemically deposited on catalytic and template multiwalled carbon nanotubes (CNTs). The catalysts supported on the entangled or straight CNTs network with open mesopores have been tested for the reaction of methanol oxidation (1M) in acidic medium (1M H2SO4) by potentiodynamic and galvanostatic methods. The high current densities (500 mA/g) for methanol oxidation proved that such a composite enables a good accessibility of the reagent molecules to the electrode interface. Contrarily, continuous layers of such metals as nickel, copper and silver were chemically and/or electrochemically deposited on carbon nanotubes. These novel materials of nanometer size can be adapted for some electronic application, e.g. nanowires.

  10. A Methanol Intoxication Outbreak From Recreational Ingestion of Fracking Fluid.

    PubMed

    Collister, David; Duff, Graham; Palatnick, Wesley; Komenda, Paul; Tangri, Navdeep; Hingwala, Jay

    2017-05-01

    Single-patient methanol intoxications are a common clinical presentation, but outbreaks are rare and usually occur in settings in which there is limited access to ethanol and methanol is consumed as a substitute. In this case report, we describe an outbreak of methanol intoxications that was challenging from a public health perspective and discuss strategies for managing such an outbreak. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  11. Activation of catalysts for synthesizing methanol from synthesis gas

    DOEpatents

    Blum, David B.; Gelbein, Abraham P.

    1985-01-01

    A method for activating a methanol synthesis catalyst is disclosed. In this method, the catalyst is slurried in an inert liquid and is activated by a reducing gas stream. The activation step occurs in-situ. That is, it is conducted in the same reactor as is the subsequent step of synthesizing methanol from a methanol gas stream catalyzed by the activated catalyst still dispersed in a slurry.

  12. Spontaneous evaluative inferences and their relationship to spontaneous trait inferences.

    PubMed

    Schneid, Erica D; Carlston, Donal E; Skowronski, John J

    2015-05-01

    Three experiments are reported that explore affectively based spontaneous evaluative impressions (SEIs) of stimulus persons. Experiments 1 and 2 used modified versions of the savings in relearning paradigm (Carlston & Skowronski, 1994) to confirm the occurrence of SEIs, indicating that they are equivalent whether participants are instructed to form trait impressions, evaluative impressions, or neither. These experiments also show that SEIs occur independently of explicit recall for the trait implications of the stimuli. Experiment 3 provides a single dissociation test to distinguish SEIs from spontaneous trait inferences (STIs), showing that disrupting cognitive processing interferes with a trait-based prediction task that presumably reflects STIs, but not with an affectively based social approach task that presumably reflects SEIs. Implications of these findings for the potential independence of spontaneous trait and evaluative inferences, as well as limitations and important steps for future study are discussed. (c) 2015 APA, all rights reserved).

  13. A micro direct methanol fuel cell demonstrator

    NASA Astrophysics Data System (ADS)

    Wozniak, Konrad; Johansson, David; Bring, Martin; Sanz-Velasco, Anke; Enoksson, Peter

    2004-09-01

    The demand for compact power sources with high energy density is increasing. A direct methanol fuel cell (DMFC) is a renewable energy source which works at near room temperature, and allows for easier liquid fuel storage, which makes it a potential candidate. We report the design, fabrication and characterization of a self-driven DMFC made by micromachining techniques and macro-assembly. Several designs were created on the basis of state-of-the-art DMFCs. A simplified mathematical model was used mainly to design the flow channels and verify the polarization curves, which reveal the output power of a cell. Silicon was used as a substrate for the fabrication of electrodes, and the membrane electrode assembly was provided by Ion Power, Inc. A 0.25 cm2 cell showed a performance of 0.29 mW cm-2 and an open circuit voltage of 0.7 V. Ten microliters of 6 M methanol solution is sufficient to operate the cell for more than 1 h.

  14. X-ray photodesorption from methanol ice

    NASA Astrophysics Data System (ADS)

    Andrade, D. P. P.; Rocco, M. L. M.; Boechat-Roberty, H. M.

    2010-12-01

    The abundances of molecules and ions depend on the mechanisms of their formation and destruction that can occur both in the gas phase and in the condensed phase on grain surfaces. Photodesorption of grain surface species may explain the relative high abundances of gaseous neutral or ionic species detected in cold environments. X-ray photons from young stars are able to penetrate cold and dense regions inside protoplanetary discs, leading to molecular dissociation and desorption of photo-products from icy molecules on grain mantles. This paper aims to experimentally investigate the contribution of ion desorption from methanol ice stimulated by soft X-rays for producing chemically active ions in protoplanetary discs. The measurements were carried out at the Brazilian synchrotron light source (LNLS), using X-ray photons at the methanol O1s resonance energy (537 eV). Some possible pathways for the H- and O- formation from singly charged desorbed ions are suggested. The photodesorption yields for positive and negative ions were determined and compared with previous results obtained using different ionization agents, such as electrons, heavy ions and photons at different energies. We also correlate our results to the ion production in protoplanetary discs.

  15. A novel process for methanol synthesis

    SciTech Connect

    Tierney, J.W.; Wender, I.

    1990-01-01

    A bench-salce reactor is being used to conduct studies of the conversion of synthesis gas to methanol by a novel process. During the last quarter, we investigated the nature of the reactions involved and the nature of the Cu-chromite catalyst being used. There is evidence that methanol is formed via a two step reaction with a methyl formate intermediate rather than by the direct hydrogenation of CO. The carbonylation reaction predominantly takes place in the liquid phase while the hydrogenolysis reaction is restricted to the surface of Cu-chromite. At steady state, the carbonylation reaction taking place in the region close to the Cu-chromite surface is probably the main source of MeF. This model also explains the increased tolerance of the process to CO. A mechanistic model is proposed to explain the interaction of different species in the reaction mixture. The topography of the Cu-chromite surface is also investigated by X-ray diffraction and scanning electron microscopy. 15 refs., 5 figs., 1 tab.

  16. Pyrotechnically Actuated Gas Generator Utilizing Aqueous Methanol

    NASA Technical Reports Server (NTRS)

    Thompson, Nathaniel B.; Karp, Ashley C.; Gallon, John C.; Tanner, Christopher L.

    2015-01-01

    A gas-generating device was developed to supplement the ram-air inflation of a supersonic ballute. The device is designed to initially pressurize the ballute following deployment, exposing and orienting its ram-air inlets to free-stream air for complete inflation. The supplemental pressurization decreases the total inflation time, and increases the likelihood of a successful inflation. The device contains a reservoir filled with an aqueous mixture of methanol that, when released in to the interior of the ballute, rapidly vaporizes due to the low ambient pressure. Upon activation of the device, a pair of redundant ring mechanisms initiate pyrotechnic charges that pressurize and rupture the reservoir, resulting in ejection of the methanol in to the ballute. In addition to its role in inflation, the device serves as the structural connection to the ballute. Analytical models were developed for the inflation capability of the device, which were verified using vacuum chamber testing of developmental hardware. Static, deployment, and environmental testing demonstrated the functionality of the ring mechanism and reservoir under several temperature and pressure conditions. Finally, the device was successfully operated during the first Supersonic Flight Dynamics Test (SFDT) of NASA's Low Density Supersonic Decelerator (LDSD) project. The design architecture is scalable to accommodate different quantities of gas generation, can be adjusted to operate in a variety of temperature and atmospheric pressure regimes, and provides a robust device that may be installed with minimal risk to personnel or hardware.

  17. Synthetic gas production for methanol--current and future trends

    SciTech Connect

    Camps, J.A.; Turnbull, D.McG.

    1980-01-01

    Methanol is one of the most easily made organic compounds and is synthesized from a gaseous mixture of carbon monoxide and hydrogen, called ''synthesis gas''. Thus the first step in the manufacture of methanol constitutes the production of synthesis gas. This paper describes various methods of producing this gas from natural gas and naphtha through reforming, coal gasification and wood gasification. Chemical plants for synthesis of methanol on industrial scales are described. Markets for methanol are reviewed, with particular attention to its use as an additive to gasoline. (Refs. 4).

  18. [Extraction of alpha-cypermethrin from aqueous methanol solutions].

    PubMed

    Shormanov, V K; Chigareva, E N; Belousova, O V

    2010-01-01

    Alpha cypermethrin was extracted from aqueous methanol solutions using hydrophobic organic solvents. The efficiency of extraction was shown to depend on the chemical nature of the solvent, the water to methanol ratio, and saturation of the aqueous methanol layer with an electrolyte. Optimal extraction of alpha-cypermethrin was achieved using toluene as the solvent under desalinization conditions. The extraction factor for the removal of the sought amount of alpha-cypermethrin from the water-methanol solution (4:1) using various solvents was calculated.

  19. Standardized treatment of severe methanol poisoning with ethanol and hemodialysis

    SciTech Connect

    Ekins, B.R.; Rollins, D.E.; Duffy, D.P.; Gregory, M.C.

    1985-03-01

    Seven patients with methanol poisoning were treated with ethanol, hemodialysis and supportive measures. The interval between ingestion and initiation of ethanol therapy varied from 3 to 67 hours and from ingestion to dialysis from 9 to 93 hours. All patients survived, but one had permanent visual impairment. A 10% ethanol solution administered intravenously is a safe and effective antidote for severe methanol poisoning. Ethanol therapy is recommended when plasma methanol concentrations are higher than 20 mg per dl, when ingested doses are greater than 30 ml and when there is evidence of acidosis or visual abnormalities in cases of suspected methanol poisoning. 13 references, 1 figure, 2 table.

  20. Biological Methanol Production by a Type II Methanotroph Methylocystis bryophila.

    PubMed

    Patel, Sanjay K S; Mardina, Primata; Kim, Sang-Yong; Lee, Jung-Kul; Kim, In-Won

    2016-04-28

    Methane (CH₄) is the most abundant component in natural gas. To reduce its harmful environmental effect as a greenhouse gas, CH₄ can be utilized as a low-cost feed for the synthesis of methanol by methanotrophs. In this study, several methanotrophs were examined for their ability to produce methanol from CH₄; including Methylocella silvestris, Methylocystis bryophila, Methyloferula stellata, and Methylomonas methanica. Among these methanotrophs, M. bryophila exhibited the highest methanol production. The optimum process parameters aided in significant enhancement of methanol production up to 4.63 mM. Maximum methanol production was observed at pH 6.8, 30°C, 175 rpm, 100 mM phosphate buffer, 50 mM MgCl₂ as a methanol dehydrogenase inhibitor, 50% CH₄ concentration, 24 h of incubation, and 9 mg of dry cell mass ml(-1) inoculum load, respectively. Optimization of the process parameters, screening of methanol dehydrogenase inhibitors, and supplementation with formate resulted in significant improvements in methanol production using M. bryophila. This report suggests, for the first time, the potential of using M. bryophila for industrial methanol production from CH₄.

  1. Antibacterial and antioxidant activity of methanol extract of Evolvulus nummularius

    PubMed Central

    Pavithra, P.S.; Sreevidya, N.; Verma, Rama S.

    2009-01-01

    Objective: To evaluate the antibacterial and antioxidant activity of methanol extract of Evolvulus nummularius (L) L. Materials and Methods: Disc diffusion and broth serial dilution tests were used to determine the antibacterial activity of the methanol extract against two Gram-positive bacterial strains (Bacillus subtilus NCIM 2718, Staphylococcus aureus ATCC 25923) and three Gram-negative bacterial strains (Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae ATCC 70063 and Escherichia coli ATCC 25922). The methanol extract was subjected to preliminary phytochemical analysis. Free radical scavenging activity of the methanol extract at different concentrations was determined with 2, 2-diphenyl-1picrylhydrazyl (DPPH). Results: The susceptible organisms to the methanol extract were Escherichia coli (MIC=12.50 mg/ml) and Bacillus subtilus (MIC=3.125 mg/ml) and the most resistant strains were Staphylococcus aureus, Klebsiella pneumoniae and Pseudomonas aeruginosa. The methanol extracts exhibited radical scavenging activity with IC50 of 350 μg/ml. Conclusion: The results from the study show that methanol extract of E.nummularius has antibacterial activity. The antioxidant activity may be attributed to the presence of tannins, flavonoids and triterpenoids in the methanol extract. The antibacterial and antioxidant activity exhibited by the methanol extract can be corroborated to the usage of this plant in Indian folk medicine. PMID:20177496

  2. Computer simulation of methanol exchange dynamics around cations and anions

    SciTech Connect

    Roy, Santanu; Dang, Liem X.

    2016-03-03

    In this paper, we present the first computer simulation of methanol exchange dynamics between the first and second solvation shells around different cations and anions. After water, methanol is the most frequently used solvent for ions. Methanol has different structural and dynamical properties than water, so its ion solvation process is different. To this end, we performed molecular dynamics simulations using polarizable potential models to describe methanol-methanol and ion-methanol interactions. In particular, we computed methanol exchange rates by employing the transition state theory, the Impey-Madden-McDonald method, the reactive flux approach, and the Grote-Hynes theory. We observed that methanol exchange occurs at a nanosecond time scale for Na+ and at a picosecond time scale for other ions. We also observed a trend in which, for like charges, the exchange rate is slower for smaller ions because they are more strongly bound to methanol. This work was supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences. The calculations were carried out using computer resources provided by the Office of Basic Energy Sciences.

  3. Fiber optic sensor for methanol quantification in biodiesel

    NASA Astrophysics Data System (ADS)

    Kawano, Marianne S.; Kamikawachi, Ricardo Canute; Fabris, José L.; Müller, Marcia

    2014-05-01

    In this work a refractometric sensor for assessment of methanol presence in biodiesel is reported. The transducer relies on the interference between the forward and back propagating modes of a single long period grating, written close to an end-face mirror optical fiber. The sensing method is thermally assisted in order to overcome the drawback caused by the high refractive index (close to the fiber cladding index) of methanol-biodiesel blends at low temperatures. Sensor showed a combined standard uncertainty of 0.6 % v/v of methanol in biodiesel for a confidence level of 68.27%, within the methanol concentration ranging from 0 to 25 % v/v.

  4. Spontaneously Combustible Solids -- A Literature Search

    DTIC Science & Technology

    1975-05-01

    hydrides, carbides, and phosphides are incompatible with water because of thý- generation of flammable, toxic, and/or explosive products. Cesium , potassium...spontaneously flammable in moist air H Cesium Amide possible explosion on contact with water Cesium Antimony Alloy spontaneously flammable Cesium Arsenic Alloy...spontaneously flammable Cesium Bismuth spontaneously flammable Cesium , Metal spontaneously flammable in moist air at room temperature Cesitnu Oxide

  5. Optical antenna enhanced spontaneous emission.

    PubMed

    Eggleston, Michael S; Messer, Kevin; Zhang, Liming; Yablonovitch, Eli; Wu, Ming C

    2015-02-10

    Atoms and molecules are too small to act as efficient antennas for their own emission wavelengths. By providing an external optical antenna, the balance can be shifted; spontaneous emission could become faster than stimulated emission, which is handicapped by practically achievable pump intensities. In our experiments, InGaAsP nanorods emitting at ∼ 200 THz optical frequency show a spontaneous emission intensity enhancement of 35 × corresponding to a spontaneous emission rate speedup ∼ 115 ×, for antenna gap spacing, d = 40 nm. Classical antenna theory predicts ∼ 2,500 × spontaneous emission speedup at d ∼ 10 nm, proportional to 1/d(2). Unfortunately, at d < 10 nm, antenna efficiency drops below 50%, owing to optical spreading resistance, exacerbated by the anomalous skin effect (electron surface collisions). Quantum dipole oscillations in the emitter excited state produce an optical ac equivalent circuit current, I(o) = qω|x(o)|/d, feeding the antenna-enhanced spontaneous emission, where q|x(o)| is the dipole matrix element. Despite the quantum-mechanical origin of the drive current, antenna theory makes no reference to the Purcell effect nor to local density of states models. Moreover, plasmonic effects are minor at 200 THz, producing only a small shift of antenna resonance frequency.

  6. Optical antenna enhanced spontaneous emission

    PubMed Central

    Eggleston, Michael S.; Messer, Kevin; Zhang, Liming; Yablonovitch, Eli; Wu, Ming C.

    2015-01-01

    Atoms and molecules are too small to act as efficient antennas for their own emission wavelengths. By providing an external optical antenna, the balance can be shifted; spontaneous emission could become faster than stimulated emission, which is handicapped by practically achievable pump intensities. In our experiments, InGaAsP nanorods emitting at ∼200 THz optical frequency show a spontaneous emission intensity enhancement of 35× corresponding to a spontaneous emission rate speedup ∼115×, for antenna gap spacing, d = 40 nm. Classical antenna theory predicts ∼2,500× spontaneous emission speedup at d ∼ 10 nm, proportional to 1/d2. Unfortunately, at d < 10 nm, antenna efficiency drops below 50%, owing to optical spreading resistance, exacerbated by the anomalous skin effect (electron surface collisions). Quantum dipole oscillations in the emitter excited state produce an optical ac equivalent circuit current, Io = qω|xo|/d, feeding the antenna-enhanced spontaneous emission, where q|xo| is the dipole matrix element. Despite the quantum-mechanical origin of the drive current, antenna theory makes no reference to the Purcell effect nor to local density of states models. Moreover, plasmonic effects are minor at 200 THz, producing only a small shift of antenna resonance frequency. PMID:25624503

  7. Optical antenna enhanced spontaneous emission

    DOE PAGES

    Eggleston, Michael S.; Messer, Kevin; Zhang, Liming; ...

    2015-01-26

    Atoms and molecules are too small to act as efficient antennas for their own emission wavelengths. By providing an external optical antenna, the balance can be shifted; spontaneous emission could become faster than stimulated emission, which is handicapped by practically achievable pump intensities. In our experiments, InGaAsP nanorods emitting at ~200 THz optical frequency show a spontaneous emission intensity enhancement of 35 × corresponding to a spontaneous emission rate speedup ~115 ×, for antenna gap spacing, d = 40 nm. Classical antenna theory predicts ~2,500 × spontaneous emission speedup at d ~10 nm, proportional to 1/d2. Unfortunately, at d spontaneous emission, where q|x(o)| is the dipole matrix element. Despite the quantum-mechanical origin of the drive current, antenna theory makes no reference to the Purcell effect nor to local density of states models. Additionally, plasmonic effects are minor at 200 THz, producing only a small shift of antenna resonance frequency.« less

  8. Methanol production from eucalyptus wood chips. Attachment IV. Health and safety aspects of the eucalypt biomass to methanol energy system

    SciTech Connect

    Fishkind, H.H.

    1982-06-01

    The basic eucalyptus-to-methanol energy process is described and possible health and safety risks are identified at all steps of the process. The toxicology and treatment for exposure to these substances are described and mitigating measures are proposed. The health and safety impacts and risks of the wood gasification/methanol synthesis system are compared to those of the coal liquefaction and conversion system. The scope of this report includes the health and safety risks of workers (1) in the laboratory and greenhouse, where eucalyptus seedlings are developed, (2) at the biomass plantation, where these seedlings are planted and mature trees harvested, (3) transporting these logs and chips to the refinery, (4) in the hammermill, where the logs and chips will be reduced to small particles, (5) in the methanol synthesis plant, where the wood particles will be converted to methanol, and (6) transporting and dispensing the methanol. Finally, the health and safety risks of consumers using methanol is discussed.

  9. Alzheimer's disease and methanol toxicity (part 1): chronic methanol feeding led to memory impairments and tau hyperphosphorylation in mice.

    PubMed

    Yang, Meifeng; Lu, Jing; Miao, Junye; Rizak, Joshua; Yang, Jianzhen; Zhai, Rongwei; Zhou, Jun; Qu, Jiagui; Wang, Jianhong; Yang, Shangchuan; Ma, Yuanye; Hu, Xintian; He, Rongqiao

    2014-01-01

    Although methanol toxicity is well known for acute neurological sequelae leading to blindness or death, there is a new impetus to investigate the chronic effects of methanol exposure. These include a recently established link between formaldehyde, a methanol metabolite, and Alzheimer's disease (AD) pathology. In the present study, mice were fed with methanol to revisit the chronic effects of methanol toxicity, especially as it pertains to AD progression. Three groups of mice (n = 9) were given either water as a control or a methanol solution (concentrations of 2% or 3.8%) over a 6-week period. The methanol-fed mice were found to have impaired spatial recognition and olfactory memory in Y-maze and olfactory memory paradigms. Immunohistochemical analysis of the mouse brains found increased neuronal tau phosphorylation in the hippocampus and an increased cellular apoptotic marker in hippocampal CA1 neurons (~10% of neurons displayed chromatin condensation) in the methanol-fed groups. Two additional in vitro experiments in mouse embryonic cerebral cortex neurons and mouse neuroblastoma N2a cells found that formaldehyde, but not methanol or the methanol end product formic acid, induced microtubule disintegration and tau protein hyperphosphorylation. The findings of the behavioral tests and immunohistochemical analysis suggested that the methanol-fed mice presented with partial AD-like symptoms. The in vitro experiments suggested that formaldehyde was most likely the detrimental component of methanol toxicity related to hippocampal tau phosphorylation and the subsequent impaired memory in the mice. These findings add to a growing body of evidence that links formaldehyde to AD pathology.

  10. Chemical mutagenesis of Gluconobacter frateurii to construct methanol-resistant mutants showing glyceric acid production from methanol-containing glycerol.

    PubMed

    Sato, Shun; Kitamoto, Dai; Habe, Hiroshi

    2014-02-01

    To produce glyceric acid (GA) from methanol-containing glycerol, resistance to methanol of Gluconobacter frateurii NBRC103465 was improved by chemical mutagenesis using N-methyl-N'-nitro-N-nitrosoguanidine. The obtained mutant Gf398 produced 6.3 g/L GA in 5% (v/v) methanol-containing 17% (w/v) glycerol medium, in which the wild-type strain neither grew nor produced GA.

  11. Te/Pt nanonetwork modified carbon fiber microelectrodes for methanol oxidation.

    PubMed

    Tsai, Hsiang-Yu; Shih, Zih-Yu; Lin, Zong-Hong; Chang, Huan-Tsung

    2013-05-17

    Te/Pt nanonetwork-decorated carbon fiber microelectrodes (CFMEs) have been fabricated and employed as anodic catalysts in a direct methanol fuel cell (DMFC). Te nanowires were prepared from tellurite ions (TeO3(2-)) through a seed-mediated growth process and were deposited onto CFMEs to form three-dimensional Te nanonetworks. The Te nanonetworks then acted as a framework and reducing agent to reduce PtCl6(2-) ions to form Te/Pt through a galvanic replacement reaction, leading to the formation of Te/PtCFMEs. By controlling the reaction time, the amount of Pt and morphology of Te/Pt nanonetworks were controlled, leading to various degrees of electrocatalytic activity. The Te/PtCFMEs provide a high electrochemical active surface area (129.2 m(2) g(-1)), good catalytic activity (1.2 A mg(-1)), high current density (20.0 mA cm(-2)), long durability, and tolerance toward the poisoning species for methanol oxidation in 0.5 M sulfuric acid containing 1 M methanol. We have further demonstrated an enhanced current density by separately using 3 and 5 Te/PtCFMEs. Our results show that the low-cost, stable, and effective Te/PtCFMEs have great potential in the fabrication of cost-effective fuel cells.

  12. Te/Pt nanonetwork modified carbon fiber microelectrodes for methanol oxidation

    NASA Astrophysics Data System (ADS)

    Tsai, Hsiang-Yu; Shih, Zih-Yu; Lin, Zong-Hong; Chang, Huan-Tsung

    2013-05-01

    Te/Pt nanonetwork-decorated carbon fiber microelectrodes (CFMEs) have been fabricated and employed as anodic catalysts in a direct methanol fuel cell (DMFC). Te nanowires were prepared from tellurite ions (TeO32-) through a seed-mediated growth process and were deposited onto CFMEs to form three-dimensional Te nanonetworks. The Te nanonetworks then acted as a framework and reducing agent to reduce PtCl62- ions to form Te/Pt through a galvanic replacement reaction, leading to the formation of Te/PtCFMEs. By controlling the reaction time, the amount of Pt and morphology of Te/Pt nanonetworks were controlled, leading to various degrees of electrocatalytic activity. The Te/PtCFMEs provide a high electrochemical active surface area (129.2 m2 g-1), good catalytic activity (1.2 A mg-1), high current density (20.0 mA cm-2), long durability, and tolerance toward the poisoning species for methanol oxidation in 0.5 M sulfuric acid containing 1 M methanol. We have further demonstrated an enhanced current density by separately using 3 and 5 Te/PtCFMEs. Our results show that the low-cost, stable, and effective Te/PtCFMEs have great potential in the fabrication of cost-effective fuel cells.

  13. Methanol-methanol and methanol-water systems: the intermolecular interactions controlling the transition from small clusters to the liquid phase.

    PubMed

    Albertí, Margarita; Amat, Anna; Aguilar, Antonio; Pirani, Fernando

    2017-06-28

    The present paper focuses on the characterization of the properties of methanol and water molecules in gas and liquid environments. A force field for methanol-methanol and methanol-water interactions, useful to be applied in Molecular Dynamics (MD) simulations, is proposed. The electrostatic interaction contributions, arising from permanent charge and/or from anisotropic charge distributions originating from permanent electric multipoles (Vel), different in gas and in liquid phases, are combined with the non electrostatic ones (Vnel), defined by means of Improved Lennard-Jones (ILJ) functions [F. Pirani et al., Phys. Chem. Chem. Phys., 2008, 10, 5489-5503]. Interestingly, the relevant parameters of the ILJ functions are not fitted to reproduce the selected properties of the systems but calculated from the molecular polarizability, which is considered the key property to define size (or Pauli) repulsion and dispersion and induction attractions. The constructed force field predicts binding energies and geometries of the methanol-methanol and methanol-water dimers, in good agreement with available data. On the other hand, several bulk and structural properties of liquid methanol, such as densities, vaporization enthalpies, diffusion coefficients, coefficients of cubic thermal expansion, heat capacities at constant pressure and some relevant radial distribution functions, calculated considering 2744 molecules and different conditions of pressure and temperature, have also been found to be in good agreement with experimental data. The study has been completed by calculating the density values at 298 K and 1 bar of some methanol-water mixtures, which have also been found to be in good agreement with experimental data.

  14. Mesoporous silica materials modified with alumina polycations as catalysts for the synthesis of dimethyl ether from methanol

    SciTech Connect

    Macina, Daniel; Piwowarska, Zofia; Tarach, Karolina; Góra-Marek, Kinga; Ryczkowski, Janusz; Chmielarz, Lucjan

    2016-02-15

    Highlights: • Deposition of alumina ologoctaions on mesoporous silicas modified with surface −SO{sub 3}H groups. • Alumina aggregates generated acid properties in the silica supports. • Alumina modified SBA-15 and MCF were active and selective catalysts in DME synthesis. - Abstract: Mesoporous silica materials (SBA-15 and MCF) were used as catalytic supports for the deposition of aggregated alumina species using the method consisting of the following steps: (i) anchoring 3-(mercaptopropyl)trimethoxysilane (MPTMS) on the silica surface followed by (ii) oxidation of −SH to−SO{sub 3}H groups and then (iii) deposition of aluminum Keggin oligocations by ion-exchange method and (iv) calcination. The obtained samples were tested as catalysts for synthesis of dimethyl ether from methanol. The modified silicas were characterized with respect to the ordering of their porous structure (XRD), textural properties (BET), chemical composition (EDS, CHNS), structure ({sup 27}Al NMR, FTIR) and location of alumina species (EDX-TEM), surface acidity (NH{sub 3}-TPD, Py-FTIR) and thermal stability (TGA). The obtained materials were found to be active and selective catalysts for methanol dehydration to dimethyl ether (DME) in the MTD process (methanol-to-dimethyl ether).

  15. Spontaneous emission and absorber theory

    NASA Astrophysics Data System (ADS)

    Pegg, David T.

    1997-01-01

    One of the long term interests of George Series was the construction of a theory of spontaneous emission which does not involve field quantisation. His approach was written in terms of atomic operators only and he drew a parallel with the Wheeler-Feynman absorber theory of radiation. By making a particular extra postulate, he was able to obtain the correct spontaneous emission rate and the Lamb shift reasonably simply and directly. An examination of his approach indicates that this postulate is physically reasonable and the need for it arises because quantisation in his theory occurs after the response of the absorber has been accounted for by means of the radiative reaction field. We review briefly an alternative absorber theory approach to spontaneous emission based on the direct action between the emitting atom and a quantised absorber, and outline some applications to more recent effects of interest in quantum optics.

  16. Spontaneous compactification and chiral fermions

    NASA Astrophysics Data System (ADS)

    Frampton, Paul H.; Yamamoto, Katsuji

    The question is addressed of which chiral fermions survive in spontaneously compactified solutions of the generalized Einstein-Yang-Mills field equations for higher even space-time dimensions. First, we study the allowed fermion representations of SU( N) which have no gauge or gravitational chiral anomalies in arbitrary even dimension and show how to find all such representations for the case of totally antisymmetric SU( N) tensors. Second, we look explicitly at monopole-induced spontaneous compactification in six dimensions; here, interesting chiral fermions in four dimensions do not occur easily but instead require highly artificial assignments of quantum numbers under the U(1) gauge group associated with the monopole. Finally, we consider instanton-induced spontaneous compactification in eight dimensions; for this case, we may readily obtain acceptable chiral fermions in four dimensions, including Georgi's three-family SU(11) model.

  17. Data mining in spontaneous reports.

    PubMed

    Bate, Andrew; Edwards, I R

    2006-03-01

    The increasing size of spontaneous report data sets and the increasing capability for screening such data due to increases in computational power has led to a recent increase in interest and use of data mining on such data. While data mining plays an important role in the analysis of spontaneous reports, there is general debate on how and when data mining should be best performed. While the cornerstone principles for data mining of spontaneous reports have been in place since the 1960s, several significant changes have occurred to make their use widespread. Superficially the Bayesian methods seem unnecessarily complex, particularly given the nature of the data, but in practice implementation in Bayesian framework gives clear benefits. There are difficulties evaluating the performance of the methods, but they work and save resources in managing large data sets. The use of neural networks allows more sophisticated pattern recognition to be performed.

  18. Nano-Engineered Catalysts for Direct Methanol Fuel Cells

    NASA Technical Reports Server (NTRS)

    Myung, Nosang; Narayanan, Sekharipuram; Wiberg, Dean

    2008-01-01

    Nano-engineered catalysts, and a method of fabricating them, have been developed in a continuing effort to improve the performances of direct methanol fuel cells as candidate power sources to supplant primary and secondary batteries in a variety of portable electronic products. In order to realize the potential for high energy densities (as much as 1.5 W h/g) of direct methanol fuel cells, it will be necessary to optimize the chemical compositions and geometric configurations of catalyst layers and electrode structures. High performance can be achieved when catalyst particles and electrode structures have the necessary small feature sizes (typically of the order of nanometers), large surface areas, optimal metal compositions, high porosity, and hydrophobicity. The present method involves electrodeposition of one or more catalytic metal(s) or a catalytic-metal/polytetrafluoroethylene nanocomposite on an alumina nanotemplate. The alumina nanotemplate is then dissolved, leaving the desired metal or metal/polytetrafluoroethylene-composite catalyst layer. Unlike some prior methods of making fine metal catalysts, this method does not involve processing at elevated temperature; all processing can be done at room temperature. In addition, this method involves fewer steps and is more amenable to scaling up for mass production. Alumina nanotemplates are porous alumina membranes that have been fabricated, variously, by anodizing either pure aluminum or aluminum that has been deposited on silicon by electronbeam evaporation. The diameters of the pores (7 to 300 nm), areal densities of pores (as much as 7 x 10(exp 10)sq cm), and lengths of pores (up to about 100 nm) can be tailored by selection of fabrication conditions. In a given case, the catalytic metal, catalytic metal alloy, or catalytic metal/ polytetrafluoroethylene composite is electrodeposited in the pores of the alumina nanotemplate. The dimensions of the pores, together with the electrodeposition conditions

  19. Evidence of anomalous behavior of intermolecular interactions at low concentration of methanol in ethanol-methanol binary system.

    PubMed

    Nilavarasi, K; Kartha, Thejus R; Madhurima, V

    2018-01-05

    At low concentrations of methanol in a binary system of ethanol and methanol, uniquely complex molecular interactions are reported here. Previous studies indicate that ethanol molecules form aggregates held together by hydrogen bonding (O-H-O) and also dispersive forces. Addition of small amount of methanol tends to break the hydrogen bond network of ethanol due to the larger polarity of methanol. This leads to the ethanol molecules becoming somewhat isolated from each other within a scaffolding network of methanol molecules, as seen from the present molecular dynamics simulations. This is an indication of a repulsive force that dominates among the two different alcohols. At higher molar concentration of methanol (Xm > 0.3817), the strength and extent (number) of formation of hydrogen bonds between ethanol and methanol increase. The geometry of molecular structure at high concentration favors the fitting of component molecules with each other. Intermolecular interactions in the ethanol-methanol binary system over the entire concentration range were investigated in detail using broadband dielectric spectroscopy, FTIR, surface tension and refractive index studies. Molecular dynamics simulations show that the hydrogen bond density is a direct function of the number of methanol molecules present, as the ethanol aggregates are not strictly hydrogen-bond constructed which is in agreement with the experimental results. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Alzheimer's disease and methanol toxicity (part 2): lessons from four rhesus macaques (Macaca mulatta) chronically fed methanol.

    PubMed

    Yang, Meifeng; Miao, Junye; Rizak, Joshua; Zhai, Rongwei; Wang, Zhengbo; Huma, Tanzeel; Li, Ting; Zheng, Na; Wu, Shihao; Zheng, Yingwei; Fan, Xiaona; Yang, Jianzhen; Wang, Jianhong; Yang, Shangchuan; Ma, Yuanye; Lü, Longbao; He, Rongqiao; Hu, Xintian

    2014-01-01

    A recently established link between formaldehyde, a methanol metabolite, and Alzheimer's disease (AD) pathology has provided a new impetus to investigate the chronic effects of methanol exposure. This paper expands this investigation to the non-human primate, rhesus macaque, through the chronic feeding of young male monkeys with 3% methanol ad libitum. Variable Spatial Delay Response Tasks of the monkeys found that the methanol feeding led to persistent memory decline in the monkeys that lasted 6 months beyond the feeding regimen. This change coincided with increases in tau protein phosphorylation at residues T181 and S396 in cerebrospinal fluid during feeding as well as with increases in tau phosphorylated aggregates and amyloid plaques in four brain regions postmortem: the frontal lobe, parietal lobe, temporal lobe, and the hippocampus. Tau phosphorylation in cerebrospinal fluid was found to be dependent on methanol feeding status, but phosphorylation changes in the brain were found to be persistent 6 months after the methanol feeding stopped. This suggested the methanol feeding caused long-lasting and persistent pathological changes that were related to AD development in the monkey. Most notably, the presence of amyloid plaque formations in the monkeys highlighted a marked difference in animal systems used in AD investigations, suggesting that the innate defenses in mice against methanol toxicity may have limited previous investigations into AD pathology. Nonetheless, these findings support a growing body of evidence that links methanol and its metabolite formaldehyde to AD pathology.

  1. Mass balance research for high electrochemical performance direct methanol fuel cells with reduced methanol crossover at various operating conditions

    NASA Astrophysics Data System (ADS)

    Park, Jun-Young; Lee, Jin-Hwa; Kang, SangKyun; Sauk, Jun-Ho; Song, Inseob

    Mass balance research in direct methanol fuel cells (DMFCs) provides a more practical method in characterizing the mass transport phenomena in a membrane electrode assembly (MEA). This method can be used to measure methanol utilization efficiency, water transport coefficient (WTC), and methanol to electricity conversion rate of a MEA in DMFCs. First, the vital design parameters of a MEA are recognized for achieving high methanol utilization efficiency with increased power density. In particular, the structural adjustment of anode diffusion layer by adding microporous layer (MPL) is a very effective way to decrease WTC with reduced methanol crossover due to the mass transfer limitation in the anode. On the other hand, the cathode MPL in the MEA design can contribute in decreasing methanol crossover. The change of structure of cathode diffusion layer is also found to be a very effective way in improving power density. In contrast, the WTC of DMFC MEAs remains virtually constant in the range of 3.4 and 3.6 irrespective of the change of the cathode GDL. The influence of operating condition on the methanol utilization efficiency, WTC, and methanol to electricity conversion rate is also presented and it is found that these mass balance properties are strongly affected by temperature, current density, methanol concentration, and the stoichiometry of fuel and air.

  2. Metabolic engineering of Corynebacterium glutamicum for methanol metabolism.

    PubMed

    Witthoff, Sabrina; Schmitz, Katja; Niedenführ, Sebastian; Nöh, Katharina; Noack, Stephan; Bott, Michael; Marienhagen, Jan

    2015-03-01

    Methanol is already an important carbon feedstock in the chemical industry, but it has found only limited application in biotechnological production processes. This can be mostly attributed to the inability of most microbial platform organisms to utilize methanol as a carbon and energy source. With the aim to turn methanol into a suitable feedstock for microbial production processes, we engineered the industrially important but nonmethylotrophic bacterium Corynebacterium glutamicum toward the utilization of methanol as an auxiliary carbon source in a sugar-based medium. Initial oxidation of methanol to formaldehyde was achieved by heterologous expression of a methanol dehydrogenase from Bacillus methanolicus, whereas assimilation of formaldehyde was realized by implementing the two key enzymes of the ribulose monophosphate pathway of Bacillus subtilis: 3-hexulose-6-phosphate synthase and 6-phospho-3-hexuloisomerase. The recombinant C. glutamicum strain showed an average methanol consumption rate of 1.7 ± 0.3 mM/h (mean ± standard deviation) in a glucose-methanol medium, and the culture grew to a higher cell density than in medium without methanol. In addition, [(13)C]methanol-labeling experiments revealed labeling fractions of 3 to 10% in the m + 1 mass isotopomers of various intracellular metabolites. In the background of a C. glutamicum Δald ΔadhE mutant being strongly impaired in its ability to oxidize formaldehyde to CO2, the m + 1 labeling of these intermediates was increased (8 to 25%), pointing toward higher formaldehyde assimilation capabilities of this strain. The engineered C. glutamicum strains represent a promising starting point for the development of sugar-based biotechnological production processes using methanol as an auxiliary substrate.

  3. Metabolic Engineering of Corynebacterium glutamicum for Methanol Metabolism

    PubMed Central

    Witthoff, Sabrina; Schmitz, Katja; Niedenführ, Sebastian; Nöh, Katharina; Noack, Stephan

    2015-01-01

    Methanol is already an important carbon feedstock in the chemical industry, but it has found only limited application in biotechnological production processes. This can be mostly attributed to the inability of most microbial platform organisms to utilize methanol as a carbon and energy source. With the aim to turn methanol into a suitable feedstock for microbial production processes, we engineered the industrially important but nonmethylotrophic bacterium Corynebacterium glutamicum toward the utilization of methanol as an auxiliary carbon source in a sugar-based medium. Initial oxidation of methanol to formaldehyde was achieved by heterologous expression of a methanol dehydrogenase from Bacillus methanolicus, whereas assimilation of formaldehyde was realized by implementing the two key enzymes of the ribulose monophosphate pathway of Bacillus subtilis: 3-hexulose-6-phosphate synthase and 6-phospho-3-hexuloisomerase. The recombinant C. glutamicum strain showed an average methanol consumption rate of 1.7 ± 0.3 mM/h (mean ± standard deviation) in a glucose-methanol medium, and the culture grew to a higher cell density than in medium without methanol. In addition, [13C]methanol-labeling experiments revealed labeling fractions of 3 to 10% in the m + 1 mass isotopomers of various intracellular metabolites. In the background of a C. glutamicum Δald ΔadhE mutant being strongly impaired in its ability to oxidize formaldehyde to CO2, the m + 1 labeling of these intermediates was increased (8 to 25%), pointing toward higher formaldehyde assimilation capabilities of this strain. The engineered C. glutamicum strains represent a promising starting point for the development of sugar-based biotechnological production processes using methanol as an auxiliary substrate. PMID:25595770

  4. Spontaneous waves in muscle fibres

    NASA Astrophysics Data System (ADS)

    Günther, Stefan; Kruse, Karsten

    2007-11-01

    Mechanical oscillations are important for many cellular processes, e.g. the beating of cilia and flagella or the sensation of sound by hair cells. These dynamic states originate from spontaneous oscillations of molecular motors. A particularly clear example of such oscillations has been observed in muscle fibers under non-physiological conditions. In that case, motor oscillations lead to contraction waves along the fiber. By a macroscopic analysis of muscle fiber dynamics we find that the spontaneous waves involve non-hydrodynamic modes. A simple microscopic model of sarcomere dynamics highlights mechanical aspects of the motor dynamics and fits with the experimental observations.

  5. Spontaneous triplet, tubal ectopic gestation.

    PubMed Central

    Nwanodi, Oroma; Berry, Robert

    2006-01-01

    Only six cases of spontaneous, unilateral, triplet ectopic gestations have previously been reported. We now present a seventh case. The patient's prior obstetrical history was significant for a term stillbirth and a term cesarean section for breech. Quantitative betahCG was normal for gestational age; however, the increased trophoblastic mass of an inappropriately implanted multiple gestation may produce sufficient betahCG to mimic an intrauterine singleton gestation. Resolution was achieved via salpingostomy. This case is significant for being spontaneously conceived and not the result of assisted reproductive technologies. Furthermore, this case supports an association between prior cesarean section and ectopic gestation. Images Figure 1 PMID:16775922

  6. Flow Friction or Spontaneous Ignition?

    NASA Technical Reports Server (NTRS)

    Stoltzfus, Joel M.; Gallus, Timothy D.; Sparks, Kyle

    2012-01-01

    "Flow friction," a proposed ignition mechanism in oxygen systems, has proved elusive in attempts at experimental verification. In this paper, the literature regarding flow friction is reviewed and the experimental verification attempts are briefly discussed. Another ignition mechanism, a form of spontaneous combustion, is proposed as an explanation for at least some of the fire events that have been attributed to flow friction in the literature. In addition, the results of a failure analysis performed at NASA Johnson Space Center White Sands Test Facility are presented, and the observations indicate that spontaneous combustion was the most likely cause of the fire in this 2000 psig (14 MPa) oxygen-enriched system.

  7. Bronchodilator, vasodilator and spasmolytic activities of methanolic extract of Myrtus communis L.

    PubMed

    Janbaz, K H; Nisa, M; Saqib, F; Imran, I; Zia-Ul-Haq, M; De Feo, V

    2013-08-01

    The present study was undertaken to validate some of the folkloric claims about the effectiveness of the use of a Myrtus communis L. crude methanol extract (Mc.Cr) in gastrointestinal, respiratory and vascular diseases. Mc.Cr caused complete relaxation of spontaneous and K⁺ (80 mM)-induced contractions in isolated rabbit jejunum. It caused right ward parallel shift of calcium concentration response curves. Mc.Cr exhibited relaxant effect on CCh- and K⁺ (80 mM)-induced contractions in isolated rabbit tracheal preparations. Furthermore, Mc.Cr caused relaxation of phenylephrine (1 μM)- and K⁺ (80 mM)-induced contractions in isolated rabbit aorta preparations. These effects were similar to verapamil, a standard calcium channel blocker. These findings could be the basis for explaining the spasmolytic, bronchodilator and vasodilator activities of the extract, through a possible calcium channel blocking activity.

  8. Low temperature catalyst system for methanol production

    DOEpatents

    Sapienza, R.S.; Slegeir, W.A.; O'Hare, T.E.

    1984-04-20

    This patent discloses a catalyst and process useful at low temperatures (150/sup 0/C) and preferably in the range 80 to 120/sup 0/C used in the production of methanol from carbon monoxide and hydrogen. The catalyst components are used in slurry form and comprise (1) a complex reducing agent derived from the component structure NaH-ROH-M(OAc)/sub 2/ where M is selected from the group consisting of Ni, Pd, and Co and R is a lower alkyl group containing 1 to 6 carbon atoms and (2) a metal carbonyl of a group VI (Mo, Cr, W) metal. For the first component, Nic is preferred (where M = Ni and R = tertiary amyl). For the second component, Mo(CO)/sub 6/ is preferred. The mixture is subjected to a conditioning or activating step under temperature and pressure, similar to the parameters given above, to afford the active catalyst.

  9. Low temperature catalysts for methanol production

    DOEpatents

    Sapienza, R.S.; Slegeir, W.A.; O'Hare, T.E.; Mahajan, D.

    1986-09-30

    A catalyst and process useful at low temperatures (below about 160 C) and preferably in the range 80--120 C used in the production of methanol from carbon monoxide and hydrogen are disclosed. The catalyst is used in slurry form and comprises a complex reducing agent derived from the component structure NaH--RONa-M(OAc)[sub 2] where M is selected from the group consisting of Ni, Pd, and Co and R is a lower alkyl group containing 1--6 carbon atoms. This catalyst is preferably used alone but is also effective in combination with a metal carbonyl of a group VI (Mo, Cr, W) metal. The preferred catalyst precursor is Nic (where M = Ni and R = tertiary amyl). Mo(CO)[sub 6] is the preferred metal carbonyl if such component is used. The catalyst is subjected to a conditioning or activating step under temperature and pressure, similar to the parameters given above, to afford the active catalyst.

  10. A novel process for methanol synthesis

    SciTech Connect

    Tierney, J.W.; Wender, I.

    1993-02-12

    A bench-scale reactor is being used to conduct studies of the conversion of synthesis gas to methanol (MeOH) in the liquid phase by a novel process. In previous reports, we provided evidence for a two step reaction in series, the carbonylation reaction mainly takng place close and the hydrogenolysis reaction taking place on the surface of the copper chromate. The interaction between the two catalyst enhances the rate of MeOH formation. In the last quarter, we showed that under present operating conditions, the methyl formate (MeOH) concentration is not in equilibrium and hence both the carboxylation and the hydrogenolysis reactions influence the rate of MEOH formation. The activities of other alkali and alkaline earth compounds as catalysts, the effect of water and the controlling reaction in the concurrent synthesis is described in this report.

  11. Mobil plans methanol plant in Nigeria

    SciTech Connect

    Alperowicz, N.

    1992-08-12

    Mobil Chemical (Houston) is in discussions with Nigerian National Petroleum Corp. (NNPC; Lagos) on a joint venture methanol plant at Port Harcourt, Nigeria. The U.S. firm has invited process owners to submit proposals for a 1-million m.t./year unit and hopes to select the technology by the end of this year. Three proposals have been submitted: Lurgi, offering its own low-pressure process; John Brown/Davy, with the ICI process; and M.W. Kellogg, proposing its own technology. Shareholding in the joint venture is yet to be decided, but it is likely to be a 50/50 tie-up. Marketing of Mobil's share or of the entire tonnage would be handled by Mobil Petrochemical International (Brussels). The plant could be onstream in late 1996.

  12. Formation of a catalyst for methanol synthesis

    SciTech Connect

    Plyasova, L.M.; Yur`eva, T.M.; Kriger, T.A.

    1995-05-01

    Formation of the structure in a copper-zinc catalyst for methanol synthesis is analyzed at each step of its preparation including hydrogen activation at which catalytically active species are formed. The necessary interaction of the catalyst components in fresh precipitates is provided by formation of mixed copper-zinc hydroxocarbonates. On low-temperature calcination, the interaction is preserved due to the formation of mixed copper-zinc oxides modified by OH{sup -} and CO{sub 3}{sup 2-} anions with copper ions distributed as clusters in a zinc oxide-type structure. The activation with hydrogen results in formation of a proton-stabilized system of zinc oxide with epitaxially bound metallic copper. Both the chemical bond cleavage and spatial phase segregation at any step of the catalyst preparation result in the loss of its catalytic activity.

  13. Lurgi, Haldor Topsoe win Statoil methanol

    SciTech Connect

    Alperowicz, N.

    1992-06-24

    Following intensive screening and evaluation of technologies, Statoil (Stavanger) and Conoco, partners in a major methanol project in Norway, have selected a Lurgi (Frankfurt)/Haldor Topsoe (Copenhagen) process combination for the NK2.6-billion ($423.5 million) plant. Capacity of the plant, which will become Europe's largest and one of the biggest in the world, will be enlarged to 1 million m.t./year (3,000 m.t./day) against earlier plants of 825,000 m.t./year. Conoco will have 18.125% in the venture and Statoil the remainder. Part of the financing will come from Statoil's own reserves. Engineering work is expected to begin almost immediately with completion planned for end-1996.

  14. Electrolytic synthesis of methanol from CO.sub.2

    DOEpatents

    Steinberg, Meyer

    1976-01-01

    A method and system for synthesizing methanol from the CO.sub.2 in air using electric power. The CO.sub.2 is absorbed by a solution of KOH to form K.sub.2 CO.sub.3 which is electrolyzed to produce methanol, a liquid hydrocarbon fuel.

  15. Methanol Oxidation Using Ozone on Titania-Supported Vanadium Catalyst

    EPA Science Inventory

    Ozone-enhanced catalytic oxidation of methanol has been conducted at mild temperatures of 100 to 250NC using V2O5/TiO2 catalyst prepared by the sol-gel method. The catalyst was characterized using XRD, surface area measurements, and temperature-programmed desorption of methanol. ...

  16. The JPL Direct Methanol Liquid-feed PEM Fuel Cell

    NASA Technical Reports Server (NTRS)

    Halpert, G.; Surampudi, S.

    1994-01-01

    Recently, there has been a breakthrough in fuel cell technology in the Energy Storage Systems Group at the Jet Propulsion Laboratory with the develpment of a direct methanol, liquid-feed, solid polymer electrolyte membrane (PEM) fuel cell... The methanol liquid-feed, solid polymer electrolyte (PEM) design has numerous system level advantages over the gas-feed design. These include:...

  17. Methanol Oxidation Using Ozone on Titania-Supported Vanadium Catalyst

    EPA Science Inventory

    Ozone-enhanced catalytic oxidation of methanol has been conducted at mild temperatures of 100 to 250NC using V2O5/TiO2 catalyst prepared by the sol-gel method. The catalyst was characterized using XRD, surface area measurements, and temperature-programmed desorption of methanol. ...

  18. METHANOL: THE CURRENT STATUS OF ENVIRONMENTAL HEALTH ISSUES

    EPA Science Inventory

    Methanol has been a topic of interest both as an environmental pollutant and as a fuel. The Clean Air Act (CAA) includes methanol in a list of 189 toxic air pollutants that the U.S. Congress identified for special consideration in the 1990 CAA Amendments. In addition, growing i...

  19. Silver catalysts in the partial oxidation of methanol to formaldehyde

    SciTech Connect

    Devochkin, A.N.; Pestryakov, A.N.; Kurina, L.N.; Sakharov, A.A.

    1992-07-20

    A comparative study of the catalytic activity of supported (Ag/pumice, LNKh-M) and bulk (Ag{sub cryst}, SD, KS) catalysts for methanol oxidation was carried out. The effect of technological parameters on the partial oxidation of methanol was studied. The optimum conditions for conducting the process on the catalysts studied were determined. 5 refs., 1 tab.

  20. METHANOL: THE CURRENT STATUS OF ENVIRONMENTAL HEALTH ISSUES

    EPA Science Inventory

    Methanol has been a topic of interest both as an environmental pollutant and as a fuel. The Clean Air Act (CAA) includes methanol in a list of 189 toxic air pollutants that the U.S. Congress identified for special consideration in the 1990 CAA Amendments. In addition, growing i...

  1. Characterization of Polyethylene-Graft-Sulfonated Polyarylsulfone Proton Exchange Membranes for Direct Methanol Fuel Cell Applications

    PubMed Central

    Kim, Hyung Kyu; Zhang, Gang; Nam, Changwoo; Chung, T.C. Mike

    2015-01-01

    This paper examines polymer film morphology and several important properties of polyethylene-graft-sulfonated polyarylene ether sulfone (PE-g-s-PAES) proton exchange membranes (PEMs) for direct methanol fuel cell applications. Due to the extreme surface energy differences between a semi-crystalline and hydrophobic PE backbone and several amorphous and hydrophilic s-PAES side chains, the PE-g-s-PAES membrane self-assembles into a unique morphology, with many proton conductive s-PAES channels embedded in the stable and tough PE matrix and a thin hydrophobic PE layer spontaneously formed on the membrane surfaces. In the bulk, these membranes show good mechanical properties (tensile strength >30 MPa, Young’s modulus >1400 MPa) and low water swelling (λ < 15) even with high IEC >3 mmol/g in the s-PAES domains. On the surface, the thin hydrophobic and semi-crystalline PE layer shows some unusual barrier (protective) properties. In addition to exhibiting higher through-plane conductivity (up to 160 mS/cm) than in-plane conductivity, the PE surface layer minimizes methanol cross-over from anode to cathode with reduced fuel loss, and stops the HO• and HO2• radicals, originally formed at the anode, entering into PEM matrix. Evidently, the thin PE surface layer provides a highly desirable protecting layer for PEMs to reduce fuel loss and increase chemical stability. Overall, the newly developed PE-g-s-PAES membranes offer a desirable set of PEM properties, including conductivity, selectivity, mechanical strength, stability, and cost-effectiveness for direct methanol fuel cell applications. PMID:26690232

  2. Characterization of Polyethylene-Graft-Sulfonated Polyarylsulfone Proton Exchange Membranes for Direct Methanol Fuel Cell Applications.

    PubMed

    Kim, Hyung Kyu; Zhang, Gang; Nam, Changwoo; Chung, T C Mike

    2015-12-04

    This paper examines polymer film morphology and several important properties of polyethylene-graft-sulfonated polyarylene ether sulfone (PE-g-s-PAES) proton exchange membranes (PEMs) for direct methanol fuel cell applications. Due to the extreme surface energy differences between a semi-crystalline and hydrophobic PE backbone and several amorphous and hydrophilic s-PAES side chains, the PE-g-s-PAES membrane self-assembles into a unique morphology, with many proton conductive s-PAES channels embedded in the stable and tough PE matrix and a thin hydrophobic PE layer spontaneously formed on the membrane surfaces. In the bulk, these membranes show good mechanical properties (tensile strength >30 MPa, Young's modulus >1400 MPa) and low water swelling (λ < 15) even with high IEC >3 mmol/g in the s-PAES domains. On the surface, the thin hydrophobic and semi-crystalline PE layer shows some unusual barrier (protective) properties. In addition to exhibiting higher through-plane conductivity (up to 160 mS/cm) than in-plane conductivity, the PE surface layer minimizes methanol cross-over from anode to cathode with reduced fuel loss, and stops the HO• and HO₂• radicals, originally formed at the anode, entering into PEM matrix. Evidently, the thin PE surface layer provides a highly desirable protecting layer for PEMs to reduce fuel loss and increase chemical stability. Overall, the newly developed PE-g-s-PAES membranes offer a desirable set of PEM properties, including conductivity, selectivity, mechanical strength, stability, and cost-effectiveness for direct methanol fuel cell applications.

  3. On the Non-Equilibrium Population Distribution of E-Methanol in Dark Clouds

    NASA Astrophysics Data System (ADS)

    Wollman, Emma

    2007-12-01

    The goal of this project was to determine the typical distribution of rotational level populations in the k=0 ladder of E-methanol in dark clouds in order to provide another observational test for theoretical models of pumping. We used our own observations of several sources with the 12-m ARO telescope on Kitt Peak as well as the published observational results by Slysh et al. (1999). The relative level populations (excitation temperatures) were determined from the measured intensity ratios of a series of the J(0)-J(-1) transitions of E-methanol under the assumption of spontaneous, optically thin emission. We observed the J(0)-J(-1) lines in six sources: W75N, DR21N, DR21, and three positions at DR21OH. The J=1 to J=5 lines were observed for all sources and the J=7 line was observed for W75N, DR21N, and one position in DR21OH. We also used Slysh et al.'s results for the J=1 through 4 lines in 52 sources, for the J=5 line in 50 sources, for the J=6 line in 15 sources, and for the J=7 and 8 lines in 2 sources. We determined the excitation temperatures of the involved levels in the k=0 ladder relative to the 1(0) level for each source and averaged the results over the sources. The average excitation temperatures demonstrate strong evidence of overcooling in the k=0 ladder - the excitation temperature increases linearly with increasing energy, from 8 K to 35 K. Our observations confirm this tendency of overcooling. We will discuss the agreement of these results with the predictions of the current models of methanol pumping. The author thanks the technical staff of the 12-m ARO telescope for help with the observations. This project was supported by the NSF/REU grant AST-0354056 and the Nantucket Maria Mitchell Association.

  4. Studies on Methanol Crossover in Liquid-Feed Direct Methanol Pem Fuel Cells

    NASA Technical Reports Server (NTRS)

    Narayanan, S. R.

    1995-01-01

    The performance of liquid feed direct methanol fuel cells using various types of Nafion membranes as the solid polymer electrolyte have been studied. The rate of fuel crossover and electrical performance has been measured for cells with Nafion membranes of various thicknesses and equivalent weights. The crossover rate is found to decrease with increasing thickness and applied current. The dependence of crossover rate on current density can be understood in terms of a simple linear diffusion model which suggests that the crossover rate can be influenced by the electrode structure in addition to the membrane. The studies suggest that Nafion EW 1500 is a very promising alternate to Nafion EW 1100 for direct methanol fuel cells.

  5. Studies on Methanol Crossover in Liquid-Feed Direct Methanol Pem Fuel Cells

    NASA Technical Reports Server (NTRS)

    Narayanan, S. R.

    1995-01-01

    The performance of liquid feed direct methanol fuel cells using various types of Nafion membranes as the solid polymer electrolyte have been studied. The rate of fuel crossover and electrical performance has been measured for cells with Nafion membranes of various thicknesses and equivalent weights. The crossover rate is found to decrease with increasing thickness and applied current. The dependence of crossover rate on current density can be understood in terms of a simple linear diffusion model which suggests that the crossover rate can be influenced by the electrode structure in addition to the membrane. The studies suggest that Nafion EW 1500 is a very promising alternate to Nafion EW 1100 for direct methanol fuel cells.

  6. Kinetic modeling of esterification reaction of surfactin-C₁₅ in methanol solution.

    PubMed

    Zhao, Yue; Yang, Shi-Zhong; Mu, Bo-Zhong

    2013-01-01

    Surfactin in methanol solution with acid would be spontaneously esterified into the mono- or dimethyl ester surfactin even at a temperature as low as 4 °C because there were two free carboxyl groups in the peptide loop of surfactin. Using trifluoroacetic acid as the catalyst, the esterification and the contents change in surfactin-C(15), mono- and dimethyl ester surfactin-C(15) with time were investigated at 4, 25, and 45 °C, respectively. The kinetic model was established for prediction of the esterification degree under experimental conditions. At 4, 25, and 45 °C, more than 10 % of the surfactin-C(15) in methanol solution in the presence of 0.05 % trifluoroacetic acid was changed into the esterified surfactin-C(15) after 37.6, 14.1, and 7.4 h, respectively. The maximum of intermediate of the mono-methyl ester surfactin-C(15) was observed at 4, 25, and 45 °C after 25, 10, and 5 days, respectively. Our results indicated that the time for preparation should be strictly controlled to avoid an unexpected esterification of surfactin during its storage and experimental treatment, and the kinetic results could be adopted as the reference condition for preparation of monomethyl ester surfactin-C(15).

  7. Toddlers' Spontaneous Attention to Number

    ERIC Educational Resources Information Center

    Baroody, Arthur J.; Li, Xia; Lai, Meng-lung

    2008-01-01

    Hannula and Lehtinen (2001, 2005) defined spontaneous focusing on numerosity (SFON) as the tendency to notice the relatively abstract attribute of number despite the presence of other attributes. According to nativists, an innate concept of one to three directs young children's attention to these "intuitive numbers" in everyday situations--even…

  8. Spontaneous Number Representation in Mosquitofish

    ERIC Educational Resources Information Center

    Dadda, Marco; Piffer, Laura; Agrillo, Christian; Bisazza, Angelo

    2009-01-01

    While there is convincing evidence that preverbal human infants and non-human primates can spontaneously represent number, considerable debate surrounds the possibility that such capacity is also present in other animals. Fish show a remarkable ability to discriminate between different numbers of social companions. Previous work has demonstrated…

  9. Spontaneous dissection of the oesophagus.

    PubMed Central

    Morritt, G N; Walbaum, P R

    1980-01-01

    Spontaneous rupture of the oesophagus is a well-known entity. Partial or intramural rupture of the oesophagus has been described but is not so well known, and the purpose of this paper is to draw attention to this condition. The clinical presentation, radiological appearances, and treatment of two such cases are described. Images PMID:7268663

  10. Spontaneous Number Representation in Mosquitofish

    ERIC Educational Resources Information Center

    Dadda, Marco; Piffer, Laura; Agrillo, Christian; Bisazza, Angelo

    2009-01-01

    While there is convincing evidence that preverbal human infants and non-human primates can spontaneously represent number, considerable debate surrounds the possibility that such capacity is also present in other animals. Fish show a remarkable ability to discriminate between different numbers of social companions. Previous work has demonstrated…

  11. Student Experiments in Spontaneous Fission.

    ERIC Educational Resources Information Center

    Becchetti, F. D.; Ying, J. S.

    1981-01-01

    Advanced undergraduate experiments utilizing a commercially available, thin spontaneous fission source are described, including studies of the energy and mass distribution of the fission fragments and their energy and angular correlation. The experiments provide a useful introduction to fission, nuclear mass equations, heavy-ion physics, and…

  12. Spontaneous emission by moving atoms

    SciTech Connect

    Meystre, P.; Wilkens, M.

    1994-12-31

    It is well known that spontaneous emission is not an intrinsic atomic property, but rather results from the coupling of the atom to the vacuum modes of the electromagnetic field. As such, it can be modified by tailoring the electromagnetic environment into which the atom can radiate. This was already realized by Purcell, who noted that the spontaneous emission rate can be enhanced if the atom placed inside a cavity is resonant with one of the cavity is resonant with one of the cavity modes, and by Kleppner, who discussed the opposite case of inhibited spontaneous emission. It has also been recognized that spontaneous emission need not be an irreversible process. Indeed, a system consisting of a single atom coupled to a single mode of the electromagnetic field undergoes a periodic exchange of excitation between the atom and the field. This periodic exchange remains dominant as long as the strength of the coupling between the atom and a cavity mode is itself dominant. 23 refs., 6 figs.

  13. Student Experiments in Spontaneous Fission.

    ERIC Educational Resources Information Center

    Becchetti, F. D.; Ying, J. S.

    1981-01-01

    Advanced undergraduate experiments utilizing a commercially available, thin spontaneous fission source are described, including studies of the energy and mass distribution of the fission fragments and their energy and angular correlation. The experiments provide a useful introduction to fission, nuclear mass equations, heavy-ion physics, and…

  14. Performance, methanol tolerance and stability of Fe-aminobenzimidazole derived catalyst for direct methanol fuel cells

    NASA Astrophysics Data System (ADS)

    Sebastián, David; Serov, Alexey; Artyushkova, Kateryna; Atanassov, Plamen; Aricò, Antonino S.; Baglio, Vincenzo

    2016-07-01

    Highly active and durable non-platinum group metals (non-PGM) catalyst based on iron-nitrogen-carbon (Fe-N-C) for the oxygen reduction reaction (ORR) derived from pyrolyzed Fe-aminobenzimidazole (Fe-ABZIM) was synthesized by sacrificial support method (SSM), and characterized by several physical-chemical techniques: scanning electron microscopy, transmission electron microscopy, Brunauer-Emmett-Teller method and X-ray photoelectron spectroscopy. In half-cell electrochemical configuration, the Fe-ABZIM catalyst presented a significant improvement of ORR activity with respect to a recently reported non-PGM formulation based on Fe-aminoantipyrine, with an enhancement of half-wave potential of about 85 mV in O2-saturated sulfuric acid solution. To the moment, the gap with respect to a benchmark Pt/C catalyst was about 90 mV. The Fe-ABZIM catalyst showed a remarkably high tolerance to methanol, resulting in superior ORR performance compared to Pt/C at methanol concentrations higher than 0.02 M. In direct methanol fuel cell (DMFC) good performances were also obtained. A durability test (100 h) at 90 °C, feeding 5 M methanol, was carried out. A certain decrease of performance was recorded, amounting to -0.20 mW cm-2 h-1 at the very beginning of test and -0.05 mW cm-2 h-1 at the end. However, the Fe-ABZIM is more adequate than previously reported formulations in terms of both ORR activity and stability.

  15. High performance direct methanol fuel cell with thin electrolyte membrane

    NASA Astrophysics Data System (ADS)

    Wan, Nianfang

    2017-06-01

    A high performance direct methanol fuel cell is achieved with thin electrolyte membrane. 320 mW cm-2 of peak power density and over 260 mW cm-2 at 0.4 V are obtained when working at 90 °C with normal pressure air supply. It is revealed that the increased anode half-cell performance with temperature contributes primarily to the enhanced performance at elevated temperature. From the comparison of iR-compensated cathode potential of methanol/air with that of H2/air fuel cell, the impact of methanol crossover on cathode performance decreases with current density and becomes negligible at high current density. Current density is found to influence fuel efficiency and methanol crossover significantly from the measurement of fuel efficiency at different current density. At high current density, high fuel efficiency can be achieved even at high temperature, indicating decreased methanol crossover.

  16. Options for the introduction of methanol as a transportation fuel

    SciTech Connect

    Nichols, R.J.; Moulton, S.; Sefer, N.; Ecklund, E.E.

    1987-01-01

    It is generally recognized that methanol is the best candidate for long-term replacement of petroleum-based fuels at some time in the future. The transition from an established fuel to a new fuel, and vehicles that can use the new fuel, is difficult, however. This paper discusses two independent investigations of possible transition uses of methanol, which, when combined, may provide an option for introduction of methanol that takes advantage of the existing industrial base, and provides economic incentives to the consumer. The concept combines the intermediate blends of methanol and gasoline (50%-70% methanol) with the Flexible Fuel Vehicle. In addition to a possible maximum cost effectiveness, these fuel ease vehicle range restriction due to refueling logistics, and mitigate cold starting problems, while at the same time providing most of the performance of the higher concentration blends.

  17. Regulation of methanol utilisation pathway genes in yeasts

    PubMed Central

    Hartner, Franz S; Glieder, Anton

    2006-01-01

    Methylotrophic yeasts such as Candida boidinii, Hansenula polymorpha, Pichia methanolica and Pichia pastoris are an emerging group of eukaryotic hosts for recombinant protein production with an ever increasing number of applications during the last 30 years. Their applications are linked to the use of strong methanol-inducible promoters derived from genes of the methanol utilisation pathway. These promoters are tightly regulated, highly repressed in presence of non-limiting concentrations of glucose in the medium and strongly induced if methanol is used as carbon source. Several factors involved in this tight control and their regulatory effects have been described so far. This review summarises available data about the regulation of promoters from methanol utilisation pathway genes. Furthermore, the role of cis and trans acting factors (e.g. transcription factors, glucose processing enzymes) in the expression of methanol utilisation pathway genes is reviewed both in the context of the native cell environment as well as in heterologous hosts. PMID:17169150

  18. Outdoor smog-chamber experiments: reactivity of methanol exhaust

    SciTech Connect

    Jeffries, H.E.; Sexton, K.G.; Holleman, M.S.

    1985-09-01

    The purpose of the report was to provide an experimental smog-chamber database especially designed to test photochemical kinetics mechanisms that would be used to assess the effects of methanol fuel use in automobiles. The mechanisms would be used in urban air-quality control models to investigate the advantages of large-scale use of methanol fuel in automobiles. The smog-chamber experiments were performed during three summer months. They have been added to the existing UNC database for photochemical mechanism validation and testing, bringing the total number of dual experiments in the database to over 400. Three different hydrocarbon mixtures were used: a 13-component mixture representing synthetic automobile exhaust; an 18-component mixture representing synthetic urban ambient hydrocarbons; and a 14-component mixture derived from the synthetic automobile exhaust by the addition of n-butane. Three different synthetic methanol-exhaust mixtures were used: 80% methanol/10% formaldehyde; and 100% methanol.

  19. Microwave Spectrum of the Ethanol-Methanol Dimer

    NASA Astrophysics Data System (ADS)

    Finneran, Ian A.; Carroll, Brandon; Mead, Griffin; Blake, Geoffrey

    2016-06-01

    The hydrogen bond donor/acceptor competition in mixed alcohol clusters remains a fundamental question in physical chemistry. Previous theoretical work on the prototype ethanol-methanol dimer has been inconclusive in predicting the energetically preferred structure. Here, we report the microwave spectrum of the ethanol-methanol dimer between 8-18 GHz, using a chirped pulse Fourier transform microwave spectrometer. With the aid of ab initio calculations, 36 transitions have been fit and assigned to a t-ethanol-acceptor, methanol-donor structure in an argon-backed expansion. In a helium-backed expansion, a second excited conformer has been observed, and tentatively assigned to a g-ethanol-acceptor, methanol-donor structure. No ethanol-donor, methanol-acceptor structures have been found, suggesting such structures are energetically disfavored.

  20. Protective effect of Urtica dioica methanol extract against experimentally induced urinary calculi in rats.

    PubMed

    Zhang, Haiying; Li, Ning; Li, Kun; Li, Peng

    2014-12-01

    Renal calculi formation is one of the most common urological disorders. Urinary stone disease is a common disease, which affects 10‑12% of the population in industrialized countries. In males, the highest prevalence of the disease occurs between the age of 20 and 40 years, while in females, the highest incidence of the disease occurs later. Previous studies have shown that long‑term exposure to oxalate is toxic to renal epithelial cells and results in oxidative stress. In the present study, a methanolic extract of aerial parts of Urtica dioica was screened for antiurolithiatic activity against ethylene glycol and ammonium chloride‑induced calcium oxalate renal stones in male rats. In the control rats, ethylene glycol and ammonium chloride administration was observed to cause an increase in urinary calcium, oxalate and creatinine levels, as well as an increase in renal calcium and oxalate deposition. Histopathological observations revealed calcium oxalate microcrystal deposits in the kidney sections of the rats treated with ethylene glycol and ammonium chloride, indicating the induction of lithiasis. In the test rats, treatment with the methanolic extract of Urtica dioica was found to decrease the elevated levels of urinary calcium, oxalate and creatinine, and significantly decrease the renal deposition of calcium and oxalate. Furthermore, renal histological observations revealed a significant reduction in calcium oxalate crystal deposition in the test rats. Phytochemical analysis of the Urtica dioica extract was also performed using liquid chromatography‑electrospray ionization tandem mass spectrometry and high-performance liquid chromatography with photodiode array detection, to determine the chemical composition of the extract. The eight chemical constituents identified in the extract were protocatechuic acid, salicylic acid, luteolin, gossypetin, rutin, kaempferol‑3‑O‑rutinoside, kaempferol‑3‑O‑glucoside and chlorogenic acid. In conclusion

  1. Security Deposits

    DTIC Science & Technology

    1987-04-01

    Tenant requirements: Provide a forwarding address. Failure by tenant to pay delinquent rent within twenty days after delivery of written demand makes...dispute boards, track down delinquent soldiers, and to actually collect the money back from the soldier. Finance cannot simply withhold pay - it can do...United States, and rents and deposits are notoriously high. Third, Fort Ord happened to be the site of a much publicized suicide by a teenage boy in

  2. Performance of vertically oriented graphene supported platinum-ruthenium bimetallic catalyst for methanol oxidation

    NASA Astrophysics Data System (ADS)

    Bo, Zheng; Hu, Dan; Kong, Jing; Yan, Jianhua; Cen, Kefa

    2015-01-01

    This work reports the electrocatalytic performance of vertically oriented graphene (VG) supported Pt-Ru bimetallic catalysts toward methanol oxidation reaction (MOR). Dense networks of VG are directly synthesized on carbon paper (CP) via a microwave plamsa-enhanced chemical vapor deposition (PECVD) method. A repeated pulse potentials approach is applied in a conventional three-electrode electrochemical system for the co-electrodeposition of Pt-Ru bimetallic nanoparticles. It is found that, the decoration of VG can simultaneously lead to a ∼3.5 times higher catalyst mass loading and a ∼50% smaller nanoparticle size than the pristine CP counterparts. An optimum Pt molar ratio of 83.4% in the deposits, achieved with a [H2PtCl6]:[RuCl3] of 1:1 in the electrolyte, is clarified with synthetically considering the mass specific activity, CO tolerance, and catalytic stability. According to Tafel analysis and cyclic voltammetry (CV) tests, the Pt-Ru/VG catalyst with the optimized Pt molar ratio can realize a faster methanol dehydrogenation than Pt/VG, and present a significantly enhanced catalytic activity (maximum current density of 339.2 mA mg-1) than those using pristine CP and Vulcan XC-72 as the supports.

  3. How the C-O bond breaks during methanol decomposition on nanocrystallites of palladium catalysts.

    PubMed

    Yudanov, Ilya V; Matveev, Alexei V; Neyman, Konstantin M; Rösch, Notker

    2008-07-23

    Experimental findings imply that edge sites (and other defects) on Pd nanocrystallites exposing mainly (111) facets in supported model catalysts are crucial for catalyst modification via deposition of CH(x) (x = 0-3) byproducts of methanol decomposition. To explore this problem computationally, we applied our recently developed approach to model realistically metal catalyst particles as moderately large three-dimensional crystallites. We present here the first results of this advanced approach where we comprehensively quantify the reactivity of a metal catalyst in an important chemical process. In particular, to unravel the mechanism of how CH(x) species are formed, we carried out density functional calculations of C-O bond scission in methanol and various dehydrogenated intermediates (CH3O, CH2OH, CH2O, CHO, CO), deposited on the cuboctahedron model particle Pd79. We calculated the lowest activation barriers, approximately 130 kJ mol(-1), of C-O bond breaking and the most favorable thermodynamics for the adsorbed species CH3O and CH2OH which feature a C-O single bond. In contrast, dissociation of adsorbed CO was characterized as negligibly slow. From the computational result that the decomposition products CH3 and CH2 preferentially adsorb at edge sites of nanoparticles, we rationalize experimental data on catalyst poisoning.

  4. Steam reforming of methanol over copper loaded anodized aluminum oxide (AAO) prepared through electrodeposition

    NASA Astrophysics Data System (ADS)

    Linga Reddy, E.; Karuppiah, J.; Lee, Hyun Chan; Kim, Dong Hyun

    2014-12-01

    In order to study the steam reforming of methanol (SRM) to produce hydrogen for fuel cells, porous γ-alumina support is developed on Al substrate using anodic oxidation process and copper catalyst particles are deposited homogeneously over anodic aluminum oxide (AAO) surface by electrodeposition method. We investigated the effect of electrodeposition time and hot water treatment (HWT) on the activity of catalysts for SRM reaction in the temperature range between 160 and 360 °C. The experimental results indicate that the SRM activity, CO2 and dimethyl ether (DME) selectivity's over Cu catalysts increased as the electrodeposition time increased from 30 to 120 s, further increment in deposition time of Cu have no significant effect on it. The rates of SRM conversion are found to be higher for the catalysts made from the supports obtained after HWT, which may be due to the enhancement in the surface area of AAO support. It is found that the SRM activity and CO2 selectivity strongly depended upon the free exposed copper sites available for methanol adsorption and reaction, and DME in products is mainly observed in the reaction temperature range between 300 and 350 °C and it is higher for the catalysts with low Cu content.

  5. Investigation on C-TiO2 nanotubes composite as Pt catalyst support for methanol electrooxidation

    NASA Astrophysics Data System (ADS)

    Sui, Xu-Lei; Wang, Zhen-Bo; Yang, Min; Huo, Li; Gu, Da-Ming; Yin, Ge-Ping

    2014-06-01

    In this paper, Pt nanoparticles have been successfully deposited on the mixture of carbon black and one-dimensional self-ordered TiO2 nanotubes (TNTs) array by a microwave-assisted polyol process to synthesize Pt/C-TNTs catalyst. TiO2 nanoparticles (TNPs) are used instead of TNTs to prepare catalyst as a reference. The obtained samples are characterized by physical characterization and electrochemical measurements. The results show that Pt nanoparticles are uniformly deposited on the three-phase interfaces between carbon and TNTs. The Pt/C-TNTs possesses substantially enhanced activity and stability in electrochemical performance. Such remarkable properties are due to the excellent composite carrier of C-TNTs: (1) TNTs has strong corrosion resistance in acidic and oxidative environment and a metal support interaction between Pt and TNTs; (2) Compared to TNPs, TNTs is more suitable for electro-catalytic field on account of its better electronic conductivity; (3) Compared to TNPs, TNTs can improve the anti-poisoning ability of catalyst for methanol oxidation. (4) Amorphous carbon can improve the dispersion of platinum particles; (5) The distribution of carbon improves the poor conductivity of TNTs. These studies indicate that Pt/C-TNTs compound is a promising catalyst for methanol electrooxidation.

  6. Modifications for use of methanol or methanol-gasoline blends in automotive vehicles, September 1976-January 1980

    SciTech Connect

    Patterson, D.J.; Bolt, J.A.; Cole, D.E.

    1980-01-01

    Methanol or blends of methanol and gasoline as automotive fuels may be attractive means for extending the nation's petroleum reserves. The present study was aimed at identifying potential problems and solutions for this use of methanol. Retrofitting of existing vehicles as well as future vehicle design have been considered. The use of ethanol or higher alcohols was not addressed in this study but will be included at a later date. Several potentially serious problems have been identified with methanol use. The most attractive solutions depend upon an integrated combination of vehicle modifications and fuel design. No vehicle problems were found which could not be solved with relatively minor developments of existing technology providing the methanol or blend fuel was itself engineered to ameliorate the solution. Research needs have been identified in the areas of lubrication and materials. These, while apparently solvable, must precede use of methanol or methanol-gasoline blends as motor fuels. Because of the substantial costs and complexities of a retrofitting program, use of methanol must be evaluated in relation to other petroleum-saving alternatives. Future vehicles can be designed initially to operate satisfactorily on these alternate fuels. However a specific fuel composition must be specified around which the future engines and vehicles can be designed.

  7. An algebraic model on the performance of a direct methanol fuel cell with consideration of methanol crossover

    NASA Astrophysics Data System (ADS)

    Yin, Ken-Ming

    An algebraic one-dimensional model on the membrane-electrode-assembly (MEA) of direct methanol fuel cell (DMFC) is proposed. Non-linear regression procedure was imposed on the model to retrieve important parameters: solid polymer electrolyte conductivity κ m, exchange current density of methanol electro-oxidation at anode catalyst surface i oM,ref, and mass diffusivity of methanol in aqueous phase within the porous electrode D a that correspond to the experimentally measured polarization curves. Although numerical iteration is required for a complete solution, the explicit relationships of methanol concentration, methanol crossover rate, oxygen concentration and cell discharge current density do provide a clear picture of the mass transport and electrochemical kinetics within the various porous media in the MEA. It is shown the cathode mixed potential induced by the parallel reactions of oxygen reduction and oxidation of crossover methanol elucidates the potential drop of the cathode and the decrease of the cell open circuit voltage (OCV). Methanol transport in the membrane is described by the diffusion, electro-osmosis, and pressure induced convection. Detailed accounts of the effects of anode methanol and cathode oxygen feed concentrations on the cell discharge performance are given with correlation to the physical structure and chemical compositions of the catalyst layers (CLs).

  8. Anaerobic treatment of methanol condensate from pulp mill compared with anaerobic treatment of methanol using mesophilic UASB reactors.

    PubMed

    Badshah, Malik; Parawira, Wilson; Mattiasson, Bo

    2012-12-01

    The feasibility of anaerobic treatment of methanol condensate from pulp and paper mill in UASB reactor was investigated and compared with the anaerobic treatment of methanol. The UASB reactor treating methanol condensate was operated for 480 days with minimum problems of overload. COD removal from methanol condensate and methanol under normal operating conditions ranged from 84-86% to 86-98%, respectively. Under optimal conditions (OLR=5.0 g COD L(-1)day(-1), COD(influent)=11.40 g L(-1)) a methane yield of 0.29 NL CH(4) per g COD(removed) (at standard temperature and pressure) was achieved during the treatment of methanol condensate. The recovery time of the microorganisms after several overloads was decreasing each time probably due to the adaptation to methanol condensate. These findings indicate that methanol condensate can be efficiently treated in a UASB reactor with the benefit of biogas production. As a bonus effect of the treatment, much of the smell of the feed was eliminated.

  9. Fabrication of ionic liquid ultrathin film by sequential deposition

    NASA Astrophysics Data System (ADS)

    Morino, Yusuke; Kanai, Yuta; Imanishi, Akihito; Yokota, Yasuyuki; Fukui, Ken-ichi

    2014-01-01

    A simple, mild, reproducible, and controllable nanodeposition method for ionic liquids (ILs) by ejection of IL solution through a high-speed electromagnetic valve (pulse valve) to a substrate under vacuum is proposed (pulse-valve method). Sequential deposition of an IL [1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (BMIM-TFSI)] on Au(111) substrates from its methanol solution was examined by adopting the pulse-valve method and the deposited IL films were analyzed by X-ray photoelectron spectroscopy (XPS) and tapping-mode atomic force microscopy (AFM). The amount of IL deposited per a pulse was successfully reduced to less than an equivalent thickness of 0.2 nm. The deposited IL was homogeneously distributed over a substrate area of 1 × 1 cm2 substrate area and the deposited amount was reproducible for independent depositions.

  10. Methanol production from Eucalyptus wood chips. Working Document 9. Economics of producing methanol from Eucalyptus in Central Florida

    SciTech Connect

    Fishkind, H.H.

    1982-06-01

    A detailed feasibility study of producing methanol from Eucalyptus in Central Florida encompasses all phases of production - from seedling to delivery of finished methanol. The project includes the following components: (1) production of 55 million, high quality, Eucalyptus seedlings through tissue culture; (2) establishment of a Eucalyptus energy plantation on approximately 70,000 acres; and (3) engineering for a 100 million gallon-per-year methanol production facility. In addition, the potential environmental impacts of the whole project were examined, safety and health aspects of producing and using methanol were analyzed, and site specific cost estimates were made. The economics of the project are presented here. Each of the three major components of the project - tissue culture lab, energy plantation, and methanol refinery - are examined individually. In each case a site specific analysis of the potential return on investment was conducted.

  11. Thermal decomposition of methanol in the sonolysis of methanol-water mixtures. Spin-trapping evidence for isotope exchange reactions

    SciTech Connect

    Krishna, C.M.; Lion, Y.; Kondo, T.; Riesz, P.

    1987-11-05

    The spin trap 3,5-dibromo-4-nitrosobenzenesulfonate was used to monitor the yield of free radicals produced during sonolysis of water-methanol mixtures. Methyl radicals and CH/sub 2/OH radicals were observed as well as the isotopically mixed radicals CH/sub 2/D and CHD/sub 2/ when CH/sub 3/OD:D/sub 2/O mixtures were studied. The results clearly show that thermal decomposition of methanol to methyl radicals occurs in the gas phase. The methyl radical yield rises sharply at very low concentrations of methanol, reaches a maximum at 5 mol dm/sup -3/ in water and decreases to a smaller value in methanol. The yield of methyl radicals as a function of methanol concentration is discussed in terms of the different factors influencing the sonochemistry.

  12. Methanol synthesis using a catalyst combination of alkali or alkaline earth salts and reduced copper chromite for methanol synthesis

    DOEpatents

    Tierney, John W.; Wender, Irving; Palekar, Vishwesh M.

    1993-01-01

    The present invention relates to a novel route for the synthesis of methanol, and more specifically to the production of methanol by contacting synthesis gas under relatively mild conditions in a slurry phase with a catalyst combination comprising reduced copper chromite and basic alkali salts or alkaline earth salts. The present invention allows the synthesis of methanol to occur in the temperature range of approximately 100.degree.-160.degree. C. and the pressure range of 40-65 atm. The process produces methanol with up to 90% syngas conversion per pass and up to 95% methanol selectivity. The only major by-product is a small amount of easily separated methyl formate. Very small amounts of water, carbon dioxide and dimethyl ether are also produced. The present catalyst combination also is capable of tolerating fluctuations in the H.sub.2 /CO ratio without major deleterious effect on the reaction rate. Furthermore, carbon dioxide and water are also tolerated without substantial catalyst deactivation.

  13. Effect of the impurities in crude bio-methanol on the performance of the direct methanol fuel cell

    NASA Astrophysics Data System (ADS)

    Tsujiguchi, Takuya; Furukawa, Takayuki; Nakagawa, Nobuyoshi

    As an environmental friendly and economical methanol for the fuel of a DMFC, we focused on a crude bio-methanol from woody biomass without refining. The effects of the impurities, i.e., ethanol, 1-butanol, methyl formate and diisopropyl ether, contained in the crude bio-methanol on the DMFC performance were investigated. Methyl formate and diisopropyl ether hardly or only slightly affected the DMFC performance, while ethanol and 1-butanol caused a significant degradation in the performance. When multiple impurities are present in the fuel as well as the crude bio-methanol, the degradation was somewhat lower than that of the single impurity, 1-butanol, which was the most harmful component of the multiple impurities. When using the crude bio-methanol as a DMFC fuel, removal of the harmful impurities, such as ethanol and 1-butanol, is necessary, otherwise a novel catalyst, which is also active for the oxidation of these impurities, required.

  14. Adaptation of Hansenula polymorpha to methanol: a transcriptome analysis

    PubMed Central

    2010-01-01

    Background Methylotrophic yeast species (e.g. Hansenula polymorpha, Pichia pastoris) can grow on methanol as sole source of carbon and energy. These organisms are important cell factories for the production of recombinant proteins, but are also used in fundamental research as model organisms to study peroxisome biology. During exponential growth on glucose, cells of H. polymorpha typically contain a single, small peroxisome that is redundant for growth while on methanol multiple, enlarged peroxisomes are present. These organelles are crucial to support growth on methanol, as they contain key enzymes of methanol metabolism. In this study, changes in the transcriptional profiles during adaptation of H. polymorpha cells from glucose- to methanol-containing media were investigated using DNA-microarray analyses. Results Two hours after the shift of cells from glucose to methanol nearly 20% (1184 genes) of the approximately 6000 annotated H. polymorpha genes were significantly upregulated with at least a two-fold differential expression. Highest upregulation (> 300-fold) was observed for the genes encoding the transcription factor Mpp1 and formate dehydrogenase, an enzyme of the methanol dissimilation pathway. Upregulated genes also included genes encoding other enzymes of methanol metabolism as well as of peroxisomal β-oxidation. A moderate increase in transcriptional levels (up to 4-fold) was observed for several PEX genes, which are involved in peroxisome biogenesis. Only PEX11 and PEX32 were higher upregulated. In addition, an increase was observed in expression of the several ATG genes, which encode proteins involved in autophagy and autophagy processes. The strongest upregulation was observed for ATG8 and ATG11. Approximately 20% (1246 genes) of the genes were downregulated. These included glycolytic genes as well as genes involved in transcription and translation. Conclusion Transcriptional profiling of H. polymorpha cells shifted from glucose to methanol showed

  15. Polymer electrolyte membrane fuel cell grade hydrogen production by methanol steam reforming: A comparative multiple reactor modeling study

    NASA Astrophysics Data System (ADS)

    Katiyar, Nisha; Kumar, Shashi; Kumar, Surendra

    2013-12-01

    Analysis of a fuel processor based on methanol steam reforming has been carried out to produce fuel cell grade H2. Six reactor configurations namely FBR1 (fixed bed reactor), MR1 (H2 selective membrane reactor with one reaction tube), MR2 (H2 selective membrane reactor with two reaction tubes), FBR2 (FBR1 + preferential CO oxidation (PROX) reactor), MR3 (MR1 + PROX), and MR4 (MR2 + PROX) are evaluated by simulation to identify the suitable processing scheme. The yield of H2 is significantly affected by H2 selective membrane, residence time, temperature, and pressure conditions at complete methanol conversion. The enhancement in residence time in MR2 by using two identical reaction tubes provides H2 yield of 2.96 with 91.25 mol% recovery at steam/methanol ratio of 1.5, pressure of 2 bar and 560 K temperature. The exit retentate gases from MR2 are further treated in PROX reactor of MR4 to reduce CO concentration to 4.1 ppm to ensure the safe discharge to the environment. The risk of carbon deposition on reforming catalyst is highly reduced in MR4, and MR4 reactor configuration generates 7.4 NL min-1 of CO free H2 from 0.12 mol min-1 of methanol which can provide 470 W PEMFC feedstock requirement. Hence, process scheme in MR4 provides a compact and innovative fuel cell grade H2 generating unit.

  16. Ultrafine particle deposition in subjects with asthma.

    PubMed

    Chalupa, David C; Morrow, Paul E; Oberdörster, Günter; Utell, Mark J; Frampton, Mark W

    2004-06-01

    Ambient air particles in the ultrafine size range (diameter < 100 nm) may contribute to the health effects of particulate matter. However, there are few data on ultrafine particle deposition during spontaneous breathing, and none in people with asthma. Sixteen subjects with mild to moderate asthma were exposed for 2 hr, by mouthpiece, to ultrafine carbon particles with a count median diameter (CMD) of 23 nm and a geometric standard deviation of 1.6. Deposition was measured during spontaneous breathing at rest (minute ventilation, 13.3 +/- 2.0 L/min) and exercise (minute ventilation, 41.9 +/- 9.0 L/min). The mean +/- SD fractional deposition was 0.76 +/- 0.05 by particle number and 0.69 +/- 0.07 by particle mass concentration. The number deposition fraction increased as particle size decreased, reaching 0.84 +/- 0.03 for the smallest particles (midpoint CMD = 8.7 nm). No differences between sexes were observed. The deposition fraction increased during exercise to 0.86 +/- 0.04 and 0.79 +/- 0.05 by particle number and mass concentration, respectively, and reached 0.93 +/- 0.02 for the smallest particles. Experimental deposition data exceeded model predictions during exercise. The deposition at rest was greater in these subjects with asthma than in previously studied healthy subjects (0.76 +/- 0.05 vs. 0.65 +/- 0.10, p < 0.001). The efficient respiratory deposition of ultrafine particles increases further in subjects with asthma. Key words: air pollution, asthma, deposition, dosimetry, inhalation, ultrafine particles.

  17. Study of catalysis for solid oxide fuel cells and direct methanol fuel cells

    NASA Astrophysics Data System (ADS)

    Jiang, Xirong

    Fuel cells offer the enticing promise of cleaner electricity with lower environmental impact than traditional energy conversion technologies. Driven by the interest in power sources for portable electronics, and distributed generation and automotive propulsion markets, active development efforts in the technologies of both solid oxide fuel cell (SOFC) and direct methanol fuel cell (DMFC) devices have achieved significant progress. However, current catalysts for fuel cells are either of low catalytic activity or extremely expensive, presenting a key barrier toward the widespread commercialization of fuel cell devices. In this thesis work, atomic layer deposition (ALD), a novel thin film deposition technique, was employed to apply catalytic Pt to SOFC, and investigate both Pt skin catalysts and Pt-Ru catalysts for methanol oxidation, a very important reaction for DMFC, to increase the activity and utilization levels of the catalysts while simultaneously reducing the catalyst loading. For SOFCs, we explored the use of ALD for the fabrication of electrode components, including an ultra-thin Pt film for use as the electrocatalyst, and a Pt mesh structure for a current collector for SOFCs, aiming for precise control over the catalyst loading and catalyst geometry, and enhancement in the current collect efficiency. We choose Pt since it has high chemical stability and excellent catalytic activity for the O2 reduction reaction and the H2 oxidation reaction even at low operating temperatures. Working SOFC fuel cells were fabricated with ALD-deposited Pt thin films as an electrode/catalyst layer. The measured fuel cell performance reveals that comparable peak power densities were achieved for ALD-deposited Pt anodes with only one-fifth of the Pt loading relative to a DC-sputtered counterpart. In addition to the continuous electrocatalyst layer, a micro-patterned Pt structure was developed via the technique of area selective ALD. By coating yttria-stabilized zirconia, a

  18. Brine shrimp cytotoxicity of crude methanol extract and antispasmodic activity of α-amyrin acetate from Tylophora hirsuta wall.

    PubMed

    Ali, Niaz

    2013-06-17

    We have previously reported that aerial parts of Tylophora hirsuta have antispasmodic profile. The current work is an attempt for isolation of pharmacologically active compound(s) that contribute for its antispasmodic activity. Preliminary phytochemical screening for crude methanol extract of Tylophora hirsuta (Th.Cr) is performed. Brine shrimp cytotoxicity of crude methanol extract is performed. Column chromatography was used for isolation of compounds. Mass spectroscopy, H(1) NMR and C(13) NMR were used for structural determination of compounds. α-amyrin acetate was tried for possible spasmolytic activity in rabbit's jejunal preparations and KCl-induced contractions. Th.Cr tested positive for saponins, alkaloids, flavonoids and terpenoids. Compound 1 was isolated as α-amyrin acetate. Compound 2 was heptaeicosanol. Crude methanol extract tested positive for brine shrimp cytotoxicity with LC(50) 492.33± 8.08 mg/ml. Compound 1 tested positive for antispasmodic activity on spontaneous rabbits' jejunum preparations with EC(50) (60 ± 2) × 10(-5)M. The compound also tested positive on KCl induced contractions with EC(50) (72 ± 3) × 10(-5)M. The present work confirms that α-amyrin acetate is has antispasmodic profile and the relaxant effect may be attributed to α-amyrin acetate which is a major compound.

  19. Brine shrimp cytotoxicity of crude methanol extract and antispasmodic activity of α-amyrin acetate from Tylophora hirsuta Wall

    PubMed Central

    2013-01-01

    Background We have previously reported that aerial parts of Tylophora hirsuta have antispasmodic profile. The current work is an attempt for isolation of pharmacologically active compound(s) that contribute for its antispasmodic activity. Methods Preliminary phytochemical screening for crude methanol extract of Tylophora hirsuta (Th.Cr) is performed. Brine shrimp cytotoxicity of crude methanol extract is performed. Column chromatography was used for isolation of compounds. Mass spectroscopy, H1 NMR and C13 NMR were used for structural determination of compounds. α-amyrin acetate was tried for possible spasmolytic activity in rabbit’s jejunal preparations and KCl-induced contractions. Results Th.Cr tested positive for saponins, alkaloids, flavonoids and terpenoids. Compound 1 was isolated as α-amyrin acetate. Compound 2 was heptaeicosanol. Crude methanol extract tested positive for brine shrimp cytotoxicity with LC50 492.33± 8.08 mg/ml. Compound 1 tested positive for antispasmodic activity on spontaneous rabbits’ jejunum preparations with EC50 (60 ± 2) × 10-5M. The compound also tested positive on KCl induced contractions with EC50 (72 ± 3) × 10-5M. Conclusions The present work confirms that α-amyrin acetate is has antispasmodic profile and the relaxant effect may be attributed to α-amyrin acetate which is a major compound. PMID:23773697

  20. Kinetics of Photoelectrochemical Oxidation of Methanol on Hematite Photoanodes

    PubMed Central

    2017-01-01

    The kinetics of photoelectrochemical (PEC) oxidation of methanol, as a model organic substrate, on α-Fe2O3 photoanodes are studied using photoinduced absorption spectroscopy and transient photocurrent measurements. Methanol is oxidized on α-Fe2O3 to formaldehyde with near unity Faradaic efficiency. A rate law analysis under quasi-steady-state conditions of PEC methanol oxidation indicates that rate of reaction is second order in the density of surface holes on hematite and independent of the applied potential. Analogous data on anatase TiO2 photoanodes indicate similar second-order kinetics for methanol oxidation with a second-order rate constant 2 orders of magnitude higher than that on α-Fe2O3. Kinetic isotope effect studies determine that the rate constant for methanol oxidation on α-Fe2O3 is retarded ∼20-fold by H/D substitution. Employing these data, we propose a mechanism for methanol oxidation under 1 sun irradiation on these metal oxide surfaces and discuss the implications for the efficient PEC methanol oxidation to formaldehyde and concomitant hydrogen evolution. PMID:28735533

  1. Methanol Uptake by Low Temperature Aqueous Sulfuric Acid Solutions

    NASA Technical Reports Server (NTRS)

    Iraci, L. T.; Essin, A. M.; Golden, D. M.; Hipskind, R. Stephen (Technical Monitor)

    2001-01-01

    The global methanol budget is currently unbalanced, with source terms significantly larger than the sinks terms. To evaluate possible losses of gaseous methanol to sulfate aerosols, the solubility and reactivity of methanol in aqueous sulfuric acid solutions representative of upper tropospheric and lower stratospheric aerosols is under investigation. Methanol will partition into sulfate aerosols according to its Henry's law solubility. Using standard uptake techniques in a Knudsen cell reactor, we have measured the effective Henry's law coefficient, H*, for cold (196 - 220 K) solutions ranging between 45 and 70 wt % H2SO4. We have found that methanol solubility ranges from approx. 10(exp 5) - 10(exp 7) M/atm for UT/LS conditions. Solubility increases with decreasing temperature and with increasing sulfuric acid content. Although methanol is slightly more soluble than are acetone and formaldehyde, current data indicate that uptake by clean aqueous sulfuric acid particles will not be a significant sink for methanol in the UT/LS. These solubility measurements include uptake due to physical solvation and any rapid equilibria which are established in solution. Reaction between primary alcohols and sulfuric acid does occur, leading to the production of alkyl sulfates. Literature values for the rate of this reaction suggest that formation of CH3OSO3H is not significant over our experimental time scale for solutions below 80 wt % H2SO4. To confirm this directly, results obtained using a complementary equilibrium measurement technique will also be presented.

  2. Waste-to-methanol: Process and economics assessment.

    PubMed

    Iaquaniello, Gaetano; Centi, Gabriele; Salladini, Annarita; Palo, Emma; Perathoner, Siglinda; Spadaccini, Luca

    2017-07-01

    The waste-to-methanol (WtM) process and related economics are assessed to evidence that WtM is a valuable solution both from economic, strategic and environmental perspectives. Bio-methanol from Refuse-derived-fuels (RdF) has an estimated cost of production of about 110€/t for a new WtM 300t/d plant. With respect to waste-to-energy (WtE) approach, this solution allows various advantages. In considering the average market cost of methanol and the premium as biofuel, the WtM approach results in a ROI (Return of Investment) of about 29%, e.g. a payback time of about 4years. In a hybrid scheme of integration with an existing methanol plant from natural gas, the cost of production becomes a profit even without considering the cap for bio-methanol production. The WtM process allows to produce methanol with about 40% and 30-35% reduction in greenhouse gas emissions with respect to methanol production from fossil fuels and bio-resources, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Methanol Production by a Broad Phylogenetic Array of Marine Phytoplankton.

    PubMed

    Mincer, Tracy J; Aicher, Athena C

    2016-01-01

    Methanol is a major volatile organic compound on Earth and serves as an important carbon and energy substrate for abundant methylotrophic microbes. Previous geochemical surveys coupled with predictive models suggest that the marine contributions are exceedingly large, rivaling terrestrial sources. Although well studied in terrestrial ecosystems, methanol sources are poorly understood in the marine environment and warrant further investigation. To this end, we adapted a Purge and Trap Gas Chromatography/Mass Spectrometry (P&T-GC/MS) method which allowed reliable measurements of methanol in seawater and marine phytoplankton cultures with a method detection limit of 120 nanomolar. All phytoplankton tested (cyanobacteria: Synechococcus spp. 8102 and 8103, Trichodesmium erythraeum, and Prochlorococcus marinus), and Eukarya (heterokont diatom: Phaeodactylum tricornutum, coccolithophore: Emiliania huxleyi, cryptophyte: Rhodomonas salina, and non-diatom heterokont: Nannochloropsis oculata) produced methanol, ranging from 0.8-13.7 micromolar in culture and methanol per total cellular carbon were measured in the ranges of 0.09-0.3%. Phytoplankton culture time-course measurements displayed a punctuated production pattern with maxima near early stationary phase. Stabile isotope labeled bicarbonate incorporation experiments confirmed that methanol was produced from phytoplankton biomass. Overall, our findings suggest that phytoplankton are a major source of methanol in the upper water column of the world's oceans.

  4. Studies on an ultrasonic atomization feed direct methanol fuel cell.

    PubMed

    Wu, Chaoqun; Liu, Linghao; Tang, Kai; Chen, Tao

    2017-01-01

    Direct methanol fuel cell (DMFC) is promising as an energy conversion device for the replacement of conventional chemical cell in future, owing to its convenient fuel storage, high energy density and low working temperature. The development of DMFC technology is currently limited by catalyst poison and methanol crossover. To alleviate the methanol crossover, a novel fuel supply system based on ultrasonic atomization is proposed. Experimental investigations on this fuel supply system to evaluate methanol permeation rates, open circuit voltages (OCVs) and polarization curves under a series of conditions have been carried out and reported in this paper. In comparison with the traditional liquid feed DMFC system, it can be found that the methanol crossover under the ultrasonic atomization feed system was significantly reduced because the DMFC reaches a large stable OCV value. Moreover, the polarization performance does not vary significantly with the liquid feed style. Therefore, the cell fed by ultrasonic atomization can be operated with a high concentration methanol to improve the energy density of DMFC. Under the supply condition of relatively high concentration methanol such as 4M and 8M, the maximum power density fed by ultrasonic atomization is higher than liquid by 6.05% and 12.94% respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Methanol Production by a Broad Phylogenetic Array of Marine Phytoplankton

    PubMed Central

    Mincer, Tracy J.; Aicher, Athena C.

    2016-01-01

    Methanol is a major volatile organic compound on Earth and serves as an important carbon and energy substrate for abundant methylotrophic microbes. Previous geochemical surveys coupled with predictive models suggest that the marine contributions are exceedingly large, rivaling terrestrial sources. Although well studied in terrestrial ecosystems, methanol sources are poorly understood in the marine environment and warrant further investigation. To this end, we adapted a Purge and Trap Gas Chromatography/Mass Spectrometry (P&T-GC/MS) method which allowed reliable measurements of methanol in seawater and marine phytoplankton cultures with a method detection limit of 120 nanomolar. All phytoplankton tested (cyanobacteria: Synechococcus spp. 8102 and 8103, Trichodesmium erythraeum, and Prochlorococcus marinus), and Eukarya (heterokont diatom: Phaeodactylum tricornutum, coccolithophore: Emiliania huxleyi, cryptophyte: Rhodomonas salina, and non-diatom heterokont: Nannochloropsis oculata) produced methanol, ranging from 0.8–13.7 micromolar in culture and methanol per total cellular carbon were measured in the ranges of 0.09–0.3%. Phytoplankton culture time-course measurements displayed a punctuated production pattern with maxima near early stationary phase. Stabile isotope labeled bicarbonate incorporation experiments confirmed that methanol was produced from phytoplankton biomass. Overall, our findings suggest that phytoplankton are a major source of methanol in the upper water column of the world’s oceans. PMID:26963515

  6. Morphological changes in the liver of rats intoxicated with methanol.

    PubMed

    Kasacka, I; Skrzydlewska, E

    1999-01-01

    On the basis of morphological examinations in light and electron microscope, the evaluation of methanol influence on the liver of rats was conducted. The examination was carried out in the group of 36 rats that were given a single dose of methanol (1.5 g/kg b.w.) into the stomach through a gastric tube. The liver was taken from rats under the ether anaesthesia after 6, 12, and 24 hours as well as after 2, 5, and 7 days of methanol administration. Results showed that methanol intoxication caused visible changes in the examined organ. Only 6 h after intoxication, lobular peripheral hepatocytes presented characteristic features of vacuolar degradation persisting up to 48 h. Since the second day of intoxication, many cells with double nuclei were found more frequently than in controls. Single hepatocytes or small hepatocytic clusters with the features of deliquescent necrosis could be seen after 5 and 7 days of examination. All animals intoxicated with methanol showed distinct weakness of glycogen reaction. The loss of glycogen resources was highest at 24 h after methanol administration. The results indicate, that methanol causes morphological changes in the rat liver and that intensification of these changes depends on the time after intoxication.

  7. Physiological response of Pichia pastoris GS115 to methanol-induced high level production of the Hepatitis B surface antigen: catabolic adaptation, stress responses, and autophagic processes.

    PubMed

    Vanz, Ana Leticia; Lünsdorf, Heinrich; Adnan, Ahmad; Nimtz, Manfred; Gurramkonda, Chandrasekhar; Khanna, Navin; Rinas, Ursula

    2012-08-08

    ERAD pathway and through the proteasome. However, the amount of HBsAg did not show any significant decline during the cultivation revealing its general protection from proteolytic degradation. During the methanol fed-batch phase, induction of vacuolar proteases (e.g. strong increase of APR1) and constitutive autophagic processes were observed. Vacuolar enclosures were mainly found around peroxisomes and not close to HBsAg deposits and, thus, were most likely provoked by peroxisomal components damaged by reactive oxygen species generated by methanol oxidation. In the methanol fed-batch phase P. pastoris is exposed to dual stress; stress resulting from methanol degradation and stress resulting from the production of the recombinant protein leading to the induction of oxidative stress and unfolded protein response pathways, respectively. Finally, the modest increase of methanol assimilatory enzymes compared to the strong increase of methanol dissimilatory enzymes suggests here a potential to increase methanol incorporation into biomass/product through metabolic enhancement of the methanol assimilatory pathway.

  8. Physiological response of Pichia pastoris GS115 to methanol-induced high level production of the Hepatitis B surface antigen: catabolic adaptation, stress responses, and autophagic processes

    PubMed Central

    2012-01-01

    proceed via the ERAD pathway and through the proteasome. However, the amount of HBsAg did not show any significant decline during the cultivation revealing its general protection from proteolytic degradation. During the methanol fed-batch phase, induction of vacuolar proteases (e.g. strong increase of APR1) and constitutive autophagic processes were observed. Vacuolar enclosures were mainly found around peroxisomes and not close to HBsAg deposits and, thus, were most likely provoked by peroxisomal components damaged by reactive oxygen species generated by methanol oxidation. Conclusions In the methanol fed-batch phase P. pastoris is exposed to dual stress; stress resulting from methanol degradation and stress resulting from the production of the recombinant protein leading to the induction of oxidative stress and unfolded protein response pathways, respectively. Finally, the modest increase of methanol assimilatory enzymes compared to the strong increase of methanol dissimilatory enzymes suggests here a potential to increase methanol incorporation into biomass/product through metabolic enhancement of the methanol assimilatory pathway. PMID:22873405

  9. Spontaneity of Communication in Individuals with Autism

    ERIC Educational Resources Information Center

    Chiang, Hsu-Min; Carter, Mark

    2008-01-01

    This article provides an examination of issues related to spontaneity of communication in children with autism. Deficits relating to spontaneity or initiation are frequently reported in individuals with autism, particularly in relation to communication and social behavior. Nevertheless, spontaneity is not necessarily clearly conceptualized or…

  10. Microbial Oxidation of Methane and Methanol: Crystallization of Methanol Dehydrogenase and Properties of Holo- and Apo-Methanol Dehydrogenase from Methylomonas methanica

    PubMed Central

    Patel, Ramesh N.; Hou, Ching T.; Felix, Andre

    1978-01-01

    Procedures are described for the purification and crystallization of methanol dehydrogenase from the soluble fraction of the type I obligate methylotroph Methylomonas methanica strain S1. The crystallized enzyme is homogeneous as judged by acrylamide gel electrophoresis and ultracentrifugation. The enzyme had a high pH optimum (9.5) and required ammonium salt as an activator. In the presence of phenazine methosulfate as an electron acceptor, the enzyme catalyzed the oxidation of primary alcohols and formaldehyde. Secondary, tertiary, and aromatic alcohols were not oxidized. The molecular weight as well as subunit size of methanol dehydrogenase was 60,000, indicating that it is monomeric. The sedimentation constant (s20,w) was 3.1S. The amino acid composition of the crystallized enzyme is also presented. Antisera prepared against the crystalline enzyme were nonspecific; they cross-reacted with and inhibited the isofunctional enzyme from other obligate methylotrophic bacteria. The crystalline methanol dehydrogenase had an absorption peak at 350 nm in the visible region and weak fluorescence peaks at 440 and 470 nm due to the presence of a pteridine derivative as the prosthetic group. A procedure was developed for the preparation of apo-methanol dehydrogenase. The molecular weights, sedimentation constants, electrophoretic mobilities, and immunological properties of apo- and holo-methanol dehydrogenases are identical. Apo-methanol dehydrogenase lacked the absorption peak at 350 nm and the fluorescence peaks at 440 and 470 nm and was catalytically inactive. All attempts to reconstitute an active enzyme from apo-methanol dehydrogenase, using various pteridine derivatives, were unsuccessful. Images PMID:415046

  11. Scaffoldless engineered enzyme assembly for enhanced methanol utilization

    DOE PAGES

    Price, J. Vincent; Chen, Long; Whitaker, W. Brian; ...

    2016-10-24

    Methanol is an important feedstock derived from natural gas and can be chemically converted into commodity and specialty chemicals at high pressure and temperature. Although biological conversion of methanol can proceed at ambient conditions, there is a dearth of engineered microorganisms that use methanol to produce metabolites. In nature, methanol dehydrogenase (Mdh), which converts methanol to formaldehyde, highly favors the reverse reaction. Thus, efficient coupling with the irreversible sequestration of formaldehyde by 3-hexulose-6-phosphate synthase (Hps) and 6-phospho-3-hexuloseisomerase (Phi) serves as the key driving force to pull the pathway equilibrium toward central metabolism. An emerging strategy to promote efficient substrate channelingmore » is to spatially organize pathway enzymes in an engineered assembly to provide kinetic driving forces that promote carbon flux in a desirable direction. Here, we report a scaffoldless, self-assembly strategy to organize Mdh, Hps, and Phi into an engineered supramolecular enzyme complex using an SH3–ligand interaction pair, which enhances methanol conversion to fructose-6-phosphate (F6P). To increase methanol consumption, an “NADH Sink” was created using Escherichia coli lactate dehydrogenase as an NADH scavenger, thereby preventing reversible formaldehyde reduction. Combination of the two strategies improved in vitro F6P production by 97-fold compared with unassembled enzymes. The beneficial effect of supramolecular enzyme assembly was also realized in vivo as the engineered enzyme assembly improved whole-cell methanol consumption rate by ninefold. This approach will ultimately allow direct coupling of enhanced F6P synthesis with other metabolic engineering strategies for the production of many desired metabolites from methanol.« less

  12. Scaffoldless engineered enzyme assembly for enhanced methanol utilization.

    PubMed

    Price, J Vincent; Chen, Long; Whitaker, W Brian; Papoutsakis, Eleftherios; Chen, Wilfred

    2016-10-24

    Methanol is an important feedstock derived from natural gas and can be chemically converted into commodity and specialty chemicals at high pressure and temperature. Although biological conversion of methanol can proceed at ambient conditions, there is a dearth of engineered microorganisms that use methanol to produce metabolites. In nature, methanol dehydrogenase (Mdh), which converts methanol to formaldehyde, highly favors the reverse reaction. Thus, efficient coupling with the irreversible sequestration of formaldehyde by 3-hexulose-6-phosphate synthase (Hps) and 6-phospho-3-hexuloseisomerase (Phi) serves as the key driving force to pull the pathway equilibrium toward central metabolism. An emerging strategy to promote efficient substrate channeling is to spatially organize pathway enzymes in an engineered assembly to provide kinetic driving forces that promote carbon flux in a desirable direction. Here, we report a scaffoldless, self-assembly strategy to organize Mdh, Hps, and Phi into an engineered supramolecular enzyme complex using an SH3-ligand interaction pair, which enhances methanol conversion to fructose-6-phosphate (F6P). To increase methanol consumption, an "NADH Sink" was created using Escherichia coli lactate dehydrogenase as an NADH scavenger, thereby preventing reversible formaldehyde reduction. Combination of the two strategies improved in vitro F6P production by 97-fold compared with unassembled enzymes. The beneficial effect of supramolecular enzyme assembly was also realized in vivo as the engineered enzyme assembly improved whole-cell methanol consumption rate by ninefold. This approach will ultimately allow direct coupling of enhanced F6P synthesis with other metabolic engineering strategies for the production of many desired metabolites from methanol.

  13. Mutagenic and cytotoxic activities of Limonium globuliferum methanol extracts.

    PubMed

    Eren, Yasin

    2016-10-01

    Unmonitored use of plant extractions alone or in combination with drugs may cause important health problems and toxic effects. Limonium (Plumbaginaceae) plants are known as antibacterial, anticancer and antivirus agent. But it is possible that this genus may have toxic effects. This study evaluated the mutagenic and cytotoxic effects of Limonium globuliferum (Boiss. et Heldr.) O. Kuntze (Plumbaginaceae) acetone/methanol (2:1), and methanol extracts of root, stem, and leaf. Different parts of this species were used in order to compare the mutagenic and cytotoxic effects of these parts. Ames test was carried out with S. typhimurium TA98, and TA100 strains. Strains were incubated at 37 °C for 72 h. MDBK cell line was used in MTT test. 10,000, 1000, 100, 10, 1 and 0.1 µg/plate concentrations of plant extracts were used in Ames test. 50, 25, 12.5, 6.25 and 3.125 µg/ml concentrations of root, stem and leaf acetone/methanol (2:1) and methanol extracts were used in MTT test. Ames test results indicated that only methanol leaf extract (10,000 µg/plate) had mutagenic activity. L. globuliferum root methanol extracts (3.125 and 6.25 µg/ml) increased the proliferation rates. Root acetone/methanol (2:1) extracts were found highly cytotoxic in all treatments. The results indicated that leaf extracts had lower cytotoxic effects than root and stem extracts. High concentrations of L. globuliferum stem and leaf methanol extracts showed cytotoxic activity in all treatment periods while low concentrations of the stem methanol extracts increased the proliferation rates.

  14. Laser cooling without spontaneous emission.

    PubMed

    Corder, Christopher; Arnold, Brian; Metcalf, Harold

    2015-01-30

    This Letter reports the demonstration of laser cooling without spontaneous emission, and thereby addresses a significant controversy. It works by restricting the atom-light interaction to a time short compared to a cycle of absorption followed by natural decay. It is achieved by using the bichromatic force on an atomic transition with a relatively long excited state lifetime and a relatively short cooling time so that spontaneous emission effects are minimized. The observed width of the one-dimensional velocity distribution is reduced by ×2 thereby reducing the "temperature" by ×4. Moreover, our results comprise a compression in phase space because the spatial expansion of the atomic sample is limited. This accomplishment is of interest to direct laser cooling of molecules or in experiments where working space or time is limited.

  15. Speeding up spontaneous disease extinction

    NASA Astrophysics Data System (ADS)

    Khasin, Michael

    2012-02-01

    The dynamics of epidemic in a susceptible population is affected both by the random character of interactions between the individuals and by environmental variations. As a consequence, the sizes of the population groups (infected, susceptible, etc.) fluctuate in the course of evolution of the epidemic. In a small community a rare large fluctuation in the number of infected can result in extinction of the disease. We suggest a novel paradigm of controlling the epidemic, where the control field, such as vaccination, is designed to maximize the rate of spontaneous disease extinction. We show that, for a limited-scope vaccination, the optimal vaccination protocol and its impact on the epidemics have universal features: (i) the vaccine must be applied in pulses, (ii) the spontaneous disease extinction is synchronized with the vaccination. We trace this universality to general properties of the response of large fluctuations to external perturbations.

  16. Spontaneous acute spinal subdural hematoma: spontaneous recovery from severe paraparesis--case report and review.

    PubMed

    Payer, Michael; Agosti, Reto

    2010-11-01

    Spontaneous idiopathic acute spinal subdural hematomas are highly exceptional. Neurological symptoms are usually severe, and rapid diagnosis with MRI is mandatory. Surgical evacuation has frequently been used therapeutically; however, spontaneous recovery in mild cases has also been reported. We present a case of spontaneous recovery from severe paraparesis after spontaneous acute SSDH, and review the English-speaking literature.

  17. [Spontaneous rupture of the ureter].

    PubMed

    Mazzoni, M P; Dalla Valle, R; Bonati, L

    1991-01-01

    A case of spontaneous rupture of the ureter initially presented as left acute abdomen in a 71 year old woman is described. A review of the literature has disclosed that in all reported cases a process directly or indirectly leading to the rupture was identified. On the basis of the clinical evolution and the radiological investigations the Authors discuss the diagnosis and the pathogenesis of the observed ureteral rupture.

  18. AGGRESSIVE TREATMENT OF SPONTANEOUS PNEUMOTHORAX

    PubMed Central

    Hecker, Sydney P.; Jamplis, Robert W.; Mitchell, Sidney P.

    1962-01-01

    In analysis of the results of treatment of 48 episodes of spontaneous pneumothorax, aggressive treatment by means of closed intercostal drainage with constant suction was found to achieve the aims of therapy more effectively than conservative measures of bed rest with or without needle aspiration. In general, full expansion of the lung was more quickly restored, recurrence was of lesser incidence, the period in hospital was shorter and the time away from work was reduced. ImagesFigure 1. PMID:13905846

  19. [Spontaneous nephro-cutaneous fistula].

    PubMed

    Bruni, R; Bartolucci, R; Biancari, F; Santoro, M

    1995-04-01

    The authors report a rare case of spontaneous nephrocutaneous fistula. The patient was asymptomatic and with a negative history for renal lithiasis, inflammation, trauma or tuberculosis. Radiological and echographical examinations permitted a complete study of the fistulous tract and the renal function; the staghorn calculi and pyelonephritis guided the decision to operate on the patient performing a nephrectomy and ureterectomy with a quick complete recovery. Biological test for micobacterium tuberculosis resulted positive after 60 days.

  20. ICI and Penspen in Nigerian and Qatari methanol deals

    SciTech Connect

    Alperowicz, N.

    1992-03-11

    The U.K. consulting and engineering company Penspen Ltd. (London) has signed a second joint venture agreement in Qatar and has selected the ICI (London) methanol process. The technology will also be used in a world-scale methanol plant in Nigeria that Penspen is helping to set up. Under the first agreement, signed on January 1 with Qatar General Petroleum Corp. (QGPC), a 50/50 venture is being formed to build a $370-million, 2,000-m.t./day methanol plant at Umm Said. ICI will provide its low-pressure technology and help market 75% of the output. Completion is due late 1994.

  1. Method validation for methanol quantification present in working places

    NASA Astrophysics Data System (ADS)

    Muna, E. D. M.; Bizarri, C. H. B.; Maciel, J. R. M.; da Rocha, G. P.; de Araújo, I. O.

    2015-01-01

    Given the widespread use of methanol by different industry sectors and high toxicity associated with this substance, it is necessary to use an analytical method able to determine in a sensitive, precise and accurate levels of methanol in the air of working environments. Based on the methodology established by the National Institute for Occupational Safety and Health (NIOSH), it was validated a methodology for determination of methanol in silica gel tubes which had demonstrated its effectiveness based on the participation of the international collaborative program sponsored by the American Industrial Hygiene Association (AIHA).

  2. A search for methanol masers at 44 GHz

    NASA Astrophysics Data System (ADS)

    Kalenskij, S. V.; Bachiller, R.; Berulis, I. I.; Val'tts, I. E.; Gomez-Gonzalez, J.; Martin-Pintado, J.; Rodriguez-Franco, A.; Slysh, V. I.

    1992-10-01

    Results of an extensive survey of young stellar objects in the methanol line 7(0) - 6(1)A(+) (44 GHz) are presented. Three new masers were detected towards cold IRAS sources in the dark clouds L 291 (GGD 27), L 379, and IC 1396 N. The new masers were also observed in 4(-1) - 3(0) E (36 GHz) and 1(0) - 0(0)A(+) (48 GHz) methanol transitions. A relationship between methanol masers and high-velocity flows with dense disks around central sources is proposed, and a possible correlation between maser emission and their intensity in the FIR is suggested.

  3. Method of producing UO2 wherein methanol wash is provided

    SciTech Connect

    Sondermann, T.

    1981-03-24

    In the production of UO2, ammonium uranyl carbonate is an intermediate product wet with water and contaminated with ammonium carbonate and is washed with methanol to remove water and ammonium carbonate. The spent methanol containing 50% water and up to 10% ammonium carbonate is subjected to rectification in a column under subatmospheric pressure with cooling the top of the tower to a low temperature to retard decomposition of ammonium carbonate and condense a liquid water fraction. Clogging of the column, vapor lines and condenser by recombination of the decomposition products is prevented. The purified methanol contains less than 5% water and may be returned for further washing of ammonium uranyl carbonate.

  4. Methanol from Wood Waste: A Technical and Economic Study.

    DTIC Science & Technology

    1977-06-01

    percent of the gas is converted to methanol , the balance passing as inerts to the boiler. The reaction is as follows: catalyst 2H + CO ’ CH3OH 2 *-3...the boiler. Catalyst life is expected to be 6 years for methanol synthesis and 2 to 3 years for the shift reactor . PLANT SIZE In a chemical processing...percent of methyl alcohol ( methanol ) in gasoline for automotive use. / At a current consumption rate of 110 billion gallons per year (gpy), 11 billion

  5. An interesting case of characteristic methanol toxicity through inhalational exposure

    PubMed Central

    Kumar, Pratyush; Gogia, Atul; Kakar, Atul; Miglani, Pratyush

    2015-01-01

    Methanol poisoning is rare but carries high risk of morbidity and mortality. Most of the cases witnessed in emergency are due to consumption of adulterated alcohol. Here we are reporting a very rare case of methanol poisoning through inhalational exposure leading to putamen necrosis and decreased visual acuity. He had dyselectrolytemia and metabolic acidosis which was successfully managed with early intervention. Its importance lies in the fact that inhalational methanol poisoning is an entity which if picked up early can prevent long-term neurological sequelae. PMID:26285665

  6. Novel Materials for High Efficiency Direct Methanol Fuel Cells

    SciTech Connect

    Carson, Stephen; Mountz, David; He, Wensheng; Zhang, Tao

    2013-12-31

    Direct methanol fuel cell membranes were developed using blends of different polyelectrolytes with PVDF. The membranes showed complex relationships between polyelectrolyte chemistry, morphology, and processing. Although the PVDF grade was found to have little effect on the membrane permselectivity, it does impact membrane conductivity and methanol permeation values. Other factors, such as varying the polyelectrolyte polarity, using varying crosslinking agents, and adjusting the equivalent weight of the membranes impacted methanol permeation, permselectivity, and areal resistance. We now understand, within the scope of the project work completed, how these inter-related performance properties can be tailored to achieve a balance of performance.

  7. Low temperature catalysts for methanol production

    DOEpatents

    Sapienza, Richard S.; Slegeir, William A.; O'Hare, Thomas E.; Mahajan, Devinder

    1986-01-01

    A catalyst and process useful at low temperatures (below about 160.degree. C.) and preferably in the range 80.degree.-120.degree. C. used in the production of methanol from carbon monoxide and hydrogen is disclosed. The catalyst is used in slurry form and comprises a complex reducing agent derived from the component structure NaH--RONa--M(OAc).sub.2 where M is selected from the group consisting of Ni, Pd, and Co and R is a lower alkyl group containing 1-6 carbon atoms. This catalyst is preferably used alone but is also effective in combination with a metal carbonyl of a group VI (Mo, Cr, W) metal. The preferred catalyst precursor is Nic (where M=Ni and R=tertiary amyl). Mo(CO).sub.6 is the preferred metal carbonyl if such component is used. The catalyst is subjected to a conditioning or activating step under temperature and pressure, similar to the parameters given above, to afford the active catalyst.

  8. Low temperature catalysts for methanol production

    DOEpatents

    Sapienza, Richard S.; Slegeir, William A.; O'Hare, Thomas E.; Mahajan, Devinder

    1986-01-01

    A catalyst and process useful at low temperatures (below about 160.degree. C.) and preferably in the range 80.degree.-120.degree. C. used in the production of methanol from carbon monoxide and hydrogen is disclosed. The catalyst is used in slurry form and comprises a complex reducing agent derived from the component structure NaH--RONa--M(OAc).sub.2 where M is selected from the group consisting of Ni, Pd, and Co and R is a lower alkyl group containing 1-6 carbon atoms. This catalyst is preferably used alone but is also effective in combination with a metal carbonyl of a group VI (Mo, Cr, W) metal. The preferred catalyst precursor is Nic (where M=Ni and R=tertiary amyl). Mo(CO).sub.6 is the preferred metal carbonyl if such component is used. The catalyst is subjected to a conditioning or activating step under temperature and pressure, similar to the parameters given above, to afford the active catalyst.

  9. Low temperature catalysts for methanol production

    DOEpatents

    Sapienza, R.S.; Slegeir, W.A.; O'Hare, T.E.; Mahajan, D.

    1986-10-28

    A catalyst and process useful at low temperatures (below about 160 C) and preferably in the range 80--120 C used in the production of methanol from carbon monoxide and hydrogen are disclosed. The catalyst is used in slurry form and comprises a complex reducing agent derived from the component structure NaH--RONa-M(OAc)[sub 2] where M is selected from the group consisting of Ni, Pd, and Co and R is a lower alkyl group containing 1-6 carbon atoms. This catalyst is preferably used alone but is also effective in combination with a metal carbonyl of a group VI (Mo, Cr, W) metal. The preferred catalyst precursor is NiC (where M = Ni and R = tertiary amyl). Mo(CO)[sub 6] is the preferred metal carbonyl if such component is used. The catalyst is subjected to a conditioning or activating step under temperature and pressure, similar to the parameters given above, to afford the active catalyst.

  10. A novel process for methanol synthesis

    SciTech Connect

    Tierney, J.W.; Wender, I.

    1992-01-01

    A bench-scale reactor is being used to study the conversion of synthesis gas to methanol (MeOH) by a novel process. In previous reports, we provided evidence that the reaction takes place in two steps. A molecule of MeOH is first carbonylated to form methyl formate (MeF) which then reacts with H{sub 2} to form two molecules of MeOH. The second reaction occurs on the surface of a heterogeneous catalyst such as copper chromite, while the first reaction requires a homegenous catalyst such as potassium methoxide (KOMe) and takes place in a non-equilibrium region in the vicinity of the heterogeneous catalyst. A synergism between the two catalysts enhances the rate of MeOH formation. In this quarter, we studied the effect of reaction conditions on the rate of formation of MeF and the effect of CO{sub 2} concentration in the feed gas on the rate of MeOH synthesis. Kinetic studies were also initiated and rate expressions were examined.

  11. Dynamical properties of water-methanol solutions.

    PubMed

    Mallamace, Francesco; Corsaro, Carmelo; Mallamace, Domenico; Vasi, Cirino; Vasi, Sebastiano; Stanley, H Eugene

    2016-02-14

    We study the relaxation times tα in the water-methanol system. We examine new data and data from the literature in the large temperature range 163 < T < 335 K obtained using different experimental techniques and focus on how tα affects the hydrogen bond structure of the system and the hydrophobicity of the alcohol methyl group. We examine the relaxation times at a fixed temperature as a function of the water molar fraction XW and observe two opposite behaviors in their curvature when the system moves from high to low T regimes. This behavior differs from that of an ideal solution in that it has excess values located at different molar fractions (XW = 0.5 for high T and 0.75 in the deep supercooled regime). We analyze the data and find that above a crossover temperature T ∼ 223 K, hydrophobicity plays a significant role and below it the water tetrahedral network dominates. This temperature is coincident with the fragile-to-strong dynamical crossover observed in confined water and supports the liquid-liquid phase transition hypothesis. At the same time, the reported data suggest that this crossover temperature (identified as the Widom line temperature) also depends on the alcohol concentration.

  12. Low temperature catalysts for methanol production

    DOEpatents

    Sapienza, R.S.; Slegeir, W.A.; O'Hare, T.E.; Mahajan, D.

    1985-03-12

    A catalyst and process useful at low temperatures (below about 160/sup 0/C) and preferably in the range 80 to 120/sup 0/C used in the production of methanol from carbon monoxide and hydrogen is disclosed. The catalyst is used in slurry form and comprises a complex reducing agent derived from the component structure NaH-RONa-M(OAc)/sub 2/ where M is selected from the group consisting of Ni, Pd, and Co and R is a lower alkyl group containing 1 to 6 carbon atoms. This catalyst is preferably used alone but is also effective in combination with a metal carbonyl of a group VI (Mo, Cr, W) metal. The preferred catalyst precursor is Nic (where M = Ni and R = tertiary amyl). Mo(CO)/sub 6/ is the preferred metal carbonyl if such component is used. The catalyst is subjected to a conditioning or activating step under temperature and pressure, similar to the parameters given above, to afford the active catalyst.

  13. Dynamical properties of water-methanol solutions

    NASA Astrophysics Data System (ADS)

    Mallamace, Francesco; Corsaro, Carmelo; Mallamace, Domenico; Vasi, Cirino; Vasi, Sebastiano; Stanley, H. Eugene

    2016-02-01

    We study the relaxation times tα in the water-methanol system. We examine new data and data from the literature in the large temperature range 163 < T < 335 K obtained using different experimental techniques and focus on how tα affects the hydrogen bond structure of the system and the hydrophobicity of the alcohol methyl group. We examine the relaxation times at a fixed temperature as a function of the water molar fraction XW and observe two opposite behaviors in their curvature when the system moves from high to low T regimes. This behavior differs from that of an ideal solution in that it has excess values located at different molar fractions (XW = 0.5 for high T and 0.75 in the deep supercooled regime). We analyze the data and find that above a crossover temperature T ˜ 223 K, hydrophobicity plays a significant role and below it the water tetrahedral network dominates. This temperature is coincident with the fragile-to-strong dynamical crossover observed in confined water and supports the liquid-liquid phase transition hypothesis. At the same time, the reported data suggest that this crossover temperature (identified as the Widom line temperature) also depends on the alcohol concentration.

  14. Spontaneous Splenic Rupture in Melanoma

    PubMed Central

    Oryan, Ahmad; Davari, Aida; Daneshbod, Khosrow; Daneshbod, Yahya

    2014-01-01

    Spontaneous rupture of spleen due to malignant melanoma is a rare situation, with only a few case reports in the literature. This study reports a previously healthy, 30-year-old man who came with chief complaint of acute abdominal pain to emergency room. On physical examination, abdominal tenderness and guarding were detected to be coincident with hypotension. Ultrasonography revealed mild splenomegaly with moderate free fluid in abdominopelvic cavity. Considering acute abdominal pain and hemodynamic instability, he underwent splenectomy with splenic rupture as the source of bleeding. Histologic examination showed diffuse infiltration by tumor. Immunohistochemical study (positive for S100, HMB45, and vimentin and negative for CK, CD10, CK20, CK7, CD30, LCA, EMA, and chromogranin) confirmed metastatic malignant melanoma. On further questioning, there was a past history of a nasal dark skin lesion which was removed two years ago with no pathologic examination. Spontaneous (nontraumatic) rupture of spleen is an uncommon situation and it happens very rarely due to neoplastic metastasis. Metastasis of malignant melanoma is one of the rare causes of the spontaneous rupture of spleen. PMID:24795827

  15. Turbulence, Spontaneous Stochasticity and Climate

    NASA Astrophysics Data System (ADS)

    Eyink, Gregory

    Turbulence is well-recognized as important in the physics of climate. Turbulent mixing plays a crucial role in the global ocean circulation. Turbulence also provides a natural source of variability, which bedevils our ability to predict climate. I shall review here a recently discovered turbulence phenomenon, called ``spontaneous stochasticity'', which makes classical dynamical systems as intrinsically random as quantum mechanics. Turbulent dissipation and mixing of scalars (passive or active) is now understood to require Lagrangian spontaneous stochasticity, which can be expressed by an exact ``fluctuation-dissipation relation'' for scalar turbulence (joint work with Theo Drivas). Path-integral methods such as developed for quantum mechanics become necessary to the description. There can also be Eulerian spontaneous stochasticity of the flow fields themselves, which is intimately related to the work of Kraichnan and Leith on unpredictability of turbulent flows. This leads to problems similar to those encountered in quantum field theory. To quantify uncertainty in forecasts (or hindcasts), we can borrow from quantum field-theory the concept of ``effective actions'', which characterize climate averages by a variational principle and variances by functional derivatives. I discuss some work with Tom Haine (JHU) and Santha Akella (NASA-Goddard) to make this a practical predictive tool. More ambitious application of the effective action is possible using Rayleigh-Ritz schemes.

  16. Spontaneous Necrosis of Choroidal Melanoma

    PubMed Central

    Thareja, Shalini; Rashid, Alia; Grossniklaus, Hans E.

    2014-01-01

    Background/Aims The purpose of this study was to examine the clinical presentations and pathological features of spontaneously necrotic choroidal melanomas. Methods The clinical and histological features of patients who underwent enucleation for uveal melanoma from 1989 to 2012 at Emory University and were found to have spontaneously necrotic choroidal melanomas were retrospectively analyzed. Results A total of 6 cases were identified. All cases had 90-100% tumor necrosis and also exhibited marked ischemic necrosis of the iris and ciliary body; 5 of 6 cases exhibited marked ischemic necrosis of the retina. The tumor consisted of melanoma ghost cells often surrounded by a zone of pigmented macrophages. Thrombi were not found in any of the cases. All of the tumors in our cases were centered around the equatorial choroid and 2 extended into the ciliary body. One of the cases exhibited a wedge-shaped infarct in a lateral aspect of the tumor. In most of the cases, microscopic areas of intact tumor cells were present in the peripheries of the tumors. Conclusions Spontaneous necrosis may occur in uveal melanoma. We believe that this occurs secondary to tumor hypoxia in the center of the tumor, followed by secondary inflammation, generalized ischemia and finally complete tumor necrosis. PMID:27175363

  17. Spontaneous Scalarization: Dead or Alive?

    NASA Astrophysics Data System (ADS)

    Berti, Emanuele; Crispino, Luis; Gerosa, Davide; Gualtieri, Leonardo; Horbatsch, Michael; Macedo, Caio; Okada da Silva, Hector; Pani, Paolo; Sotani, Hajime; Sperhake, Ulrich

    2015-04-01

    In 1993, Damour and Esposito-Farese showed that a wide class of scalar-tensor theories can pass weak-field gravitational tests and exhibit nonperturbative strong-field deviations away from General Relativity in systems involving neutron stars. These deviations are possible in the presence of ``spontaneous scalarization,'' a phase transition similar in nature to spontaneous magnetization in ferromagnets. More than twenty years after the original proposal, binary pulsar experiments have severely constrained the possibility of spontaneous scalarization occurring in nature. I will show that these experimental constraints have important implications for the torsional oscillation frequencies of neutron stars and for the so-called ``I-Love-Q'' relations in scalar-tensor theories. I will also argue that there is still hope to observe strong scalarization effects, despite the strong experimental bounds on the original mechanism. In particular, I will discuss two mechanisms that could produce strong scalarization in neutron stars: anisotropy and multiscalarization. This work was supported by NSF CAREER Award PHY-1055103.

  18. Performance of composite Nafion/PVA membranes for direct methanol fuel cells

    NASA Astrophysics Data System (ADS)

    Mollá, Sergio; Compañ, Vicente

    2011-03-01

    This work has been focused on the characterization of the methanol permeability and fuel cell performance of composite Nafion/PVA membranes in function of their thickness, which ranged from 19 to 97 μm. The composite membranes were made up of Nafion® polymer deposited between polyvinyl alcohol (PVA) nanofibers. The resistance to methanol permeation of the Nafion/PVA membranes shows a linear variation with the thickness. The separation between apparent and true permeability permits to give an estimated value of 4.0 × 10-7 cm2 s-1 for the intrinsic or true permeability of the bulk phase at the composite membranes. The incorporation of PVA nanofibers causes a remarkable reduction of one order of magnitude in the methanol permeability as compared with pristine Nafion® membranes. The DMFC performances of membrane-electrode assemblies prepared from Nafion/PVA and pristine Nafion® membranes were tested at 45, 70 and 95 °C under various methanol concentrations, i.e., 1, 2 and 3 M. The nanocomposite membranes with thicknesses of 19 μm and 47 μm reached power densities of 211 mW cm-2 and 184 mW cm-2 at 95 °C and 2 M methanol concentration. These results are comparable to those found for Nafion® membranes with similar thickness at the same conditions, which were 210 mW cm-2 and 204 mW cm-2 respectively. Due to the lower amount of Nafion® polymer present within the composite membranes, it is suggested a high degree of utilization of Nafion® as proton conductive material within the Nafion/PVA membranes, and therefore, significant savings in the consumed amount of Nafion® are potentially able to be achieved. In addition, the reinforcement effect caused by the PVA nanofibers offers the possibility of preparing membranes with very low thickness and good mechanical properties, while on the other hand, pristine Nafion® membranes are unpractical below a thickness of 50 μm.

  19. The spontaneous puncture of thick liquid films

    NASA Astrophysics Data System (ADS)

    Néel, Baptiste; Villermaux, Emmanuel

    2016-11-01

    We call thick those films for which the disjoining pressure is ineffective. Water films with thickness h in the 1-10 μm range are thick, but it is also known that, paradoxically, they nucleate holes spontaneously. We have uncovered a mechanism solving the paradox. Most natural films are dirty to some extent, and we show that if a spot of dissolved substance lowers locally the surface tension of the liquid, the corresponding Marangoni stress may lead to a self-sustained instability triggering film rupture. When deposited with size a, the spot dissipates by molecular diffusion (coefficient D) along the film in a time a2 / D . Before doing so, the surface tension gradient Δσ / a between the spot center (tension σ - Δσ) and the rest of the film (tension σ) induces an inhomogeneous outward interstitial flow which digs the spot, and reinforces the tension gradient. Hence the instability, which occurs within a timescale τ √{ ρa2 h / Δσ } , with ρ the liquid density. When the Péclet number Pe =a2 / Dτ is small, diffusion regularizes the film, which remains flat: clean films don't break, while for Pe > 1 , the film punctures. This new scenario will be illustrated by several experiments.

  20. Spontaneous growth of vector fields in gravity

    NASA Astrophysics Data System (ADS)

    Ramazanoǧlu, Fethi M.

    2017-09-01

    We show that the spontaneous scalarization scenario in scalar-tensor theories is a specific case of a more general phenomenon. The key fact is that the instability causing the spontaneous growth in scalars is due to the nonminimal coupling in the theory, and not related to the nature of the scalar. Another field with the same form of coupling undergoes spontaneous growth as well. We explicitly demonstrate this idea for vectors, naming it "spontaneous vectorization", and study spherically symmetric neutron stars in such a theory. We also comment on other tensor fields the idea can be applied, naming the general mechanism "spontaneous tensorization."

  1. Effect of pervaporation plate thickness on the rate of methanol evaporation in a passive vapor-feed direct methanol fuel cell

    NASA Astrophysics Data System (ADS)

    Fauzi, N. F. I.; Hasran, U. A.; Kamarudin, S. K.

    2015-09-01

    In a passive vapor-feed direct methanol fuel cell (DMFC), methanol vapor is typically obtained using a pervaporation plate in a process by which liquid methanol contained in the fuel reservoir undergoes a phase change to vapor in the anodic vapor chamber. This work investigates the effect of pervaporation plate thickness on the rate of methanol evaporation using a three-dimensional simulation model developed by varying the plate thickness. A. The rate of methanol evaporation was measured using Darcy's law. The rate of methanol evaporation was found to be inversely proportional to the plate thickness, where the decrease in thickness inevitably lowers the resistance along the plate and consequently increases the methanol transport through the plate. This shows that the plate thickness has a significant influence on the rate of methanol evaporation and thereby plays an important role in improving the performance of the passive vapor-feed direct methanol fuel cell.

  2. Hydrogen and methanol exchange processes for (TMP)Rh-OCH3(CH3OH) in binary solutions of methanol and benzene.

    PubMed

    Sarkar, Sounak; Li, Shan; Wayland, Bradford B

    2011-04-18

    Tetramesityl porphinato rhodium(III) methoxide ((TMP)Rh-OCH(3)) binds with methanol in benzene to form a 1:1 methanol complex ((TMP)Rh-OCH(3)(CH(3)OH)) (1). Dynamic processes are observed to occur for the rhodium(III) methoxide methanol complex (1) that involve both hydrogen and methanol exchange. Hydrogen exchange between coordinated methanol and methoxide through methanol in solution results in an interchange of the environments for the non-equivalent porphyrin faces that contain methoxide and methanol ligands. Interchange of the environments of the coordinated methanol and methoxide sites in 1 produces interchange of the inequivalent mesityl o-CH(3) groups, but methanol ligand exchange occurs on one face of the porphyrin and the mesityl o-CH(3) groups remain inequivalent. Rate constants for dynamic processes are evaluated by full line shape analysis for the (1)H NMR of the mesityl o-CH(3) and high field methyl resonances of coordinated methanol and methoxide groups in 1. The rate constant for interchange of the inequivalent porphyrin faces is associated with hydrogen exchange between 1 and methanol in solution and is observed to increase regularly with the increase in the mole fraction of methanol. The rate constant for methanol ligand exchange between 1 and the solution varies with the solution composition and fluctuates in a manner that parallels the change in the activation energy for methanol diffusion which is a consequence of solution non-ideality from hydrogen bonded clusters.

  3. Spontaneous Gamma Activity in Schizophrenia.

    PubMed

    Hirano, Yoji; Oribe, Naoya; Kanba, Shigenobu; Onitsuka, Toshiaki; Nestor, Paul G; Spencer, Kevin M

    2015-08-01

    A major goal of translational neuroscience is to identify neural circuit abnormalities in neuropsychiatric disorders that can be studied in animal models to facilitate the development of new treatments. Oscillations in the gamma band (30-100 Hz) of the electroencephalogram have received considerable interest as the basic mechanisms underlying these oscillations are understood, and gamma abnormalities have been found in schizophrenia (SZ). Animal models of SZ based on hypofunction of the N-methyl-d-aspartate receptor (NMDAR) demonstrate increased spontaneous broadband gamma power, but this phenomenon has not been identified clearly in patients with SZ. To examine spontaneous gamma power and its relationship to evoked gamma oscillations in the auditory cortex of patients with SZ. We performed a cross-sectional study including 24 patients with chronic SZ and 24 matched healthy control participants at the Veterans Affairs Boston Healthcare System from January 1, 2009, through December 31, 2012. Electroencephalograms were obtained during auditory steady-state stimulation at multiple frequencies (20, 30, and 40 Hz) and during a resting state in 18 participants in each group. Electroencephalographic activity in the auditory cortex was estimated using dipole source localization. Auditory steady-state response (ASSR) measures included the phase-locking factor and evoked power. Spontaneous gamma power was measured as induced (non-phase-locked) gamma power in the ASSR data and as total gamma power in the resting-state data. The ASSR phase-locking factor was reduced significantly in patients with SZ compared with controls for the 40-Hz stimulation (mean [SD], 0.075 [0.028] vs 0.113 [0.065]; F1,46 = 6.79 [P = .012]) but not the 20- or the 30-Hz stimulation (0.042 [0.038] vs 0.043 [0.034]; F1,46 = 0.006 [P = .938] and 0.084 [0.040] vs 0.098 [0.050]; F1,46 = 1.605 [P = .212], respectively), repeating previous findings. The mean [SD] broadband-induced (30

  4. Reduced graphene oxide (RGO)-supported NiCo2O4 nanoparticles: an electrocatalyst for methanol oxidation

    NASA Astrophysics Data System (ADS)

    Das, Ashok Kumar; Layek, Rama K.; Kim, Nam Hoon; Jung, Daeseung; Lee, Joong Hee

    2014-08-01

    The design and development of cheap, highly active, and durable non-platinum (Pt)-based electrocatalysts for methanol electrooxidation is highly desirable, but is a challenging task. In this paper, we demonstrate the application of a hydrothermally synthesized NiCo2O4-reduced graphene oxide (RGO) composite as an electrocatalyst for the electrochemical oxidation of methanol in alkaline pH. The physicochemical properties of the NiCo2O4-RGO composite were investigated via Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Raman spectroscopy (RS), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) measurements. The physical characterization methods confirm the deposition of NiCo2O4 nanoparticles on the RGO surface. The TEM image shows that the NiCo2O4 nanoparticles with an average size of ~10 nm are distributed over the RGO surface. Compared to RGO and NiCo2O4 nanoparticles, the NiCo2O4-RGO-based electrode shows excellent electrocatalytic activity for the oxidation of methanol in alkaline pH. On the NiCo2O4-RGO-based electrode, the oxidation of methanol occurs at ~0.6 V with a higher catalytic current density, and the response is highly stable. The excellent electrocatalytic activity of the NiCo2O4-RGO composite is attributed to the synergistic effects between the NiCo2O4 nanoparticles and RGO. Since the NiCo2O4-RGO composite shows a highly stable response during methanol oxidation reaction, it is a very promising material to be used as an electrocatalyst in the development of high performance non-Pt based alkaline fuel cells.The design and development of cheap, highly active, and durable non-platinum (Pt)-based electrocatalysts for methanol electrooxidation is highly desirable, but is a challenging task. In this paper, we demonstrate the application of a hydrothermally synthesized NiCo2O4-reduced graphene oxide (RGO) composite as an electrocatalyst for the electrochemical

  5. Evaluation of wound healing potential of methanolic Crinum jagus bulb extract

    PubMed Central

    Udegbunam, Sunday Ositadimma; Kene, Raphael Okoli Chukwujekwu; Anika, Silvanus Maduka; Udegbunam, Rita Ijeoma; Nnaji, Theophilus Okafor; Anyanwu, Madubuike Umunna

    2015-01-01

    Objective: Crinum jagus (J. Thomps.) Dandy commonly called Harmattan or St. Christopher’s lily belonging to the family Liliaceae is widely used traditionally in Southeastern Nigeria for treatment of skin sores. This study investigated the wound healing potentials of methanolic C. jagus bulb extract (MCJBE) using incision, excision, and dead space wound healing models. Materials and Methods: Phytochemical screening showed the presence of alkaloids, glycosides, tannins, saponins in the extract, but absence of flavonoids. In the incision and dead space wound models, rats were dosed orally with 300 mg/kg body weight (bw) of 10 and 5% of MCJBE solution, respectively, while in the excision wound model, rats were treated topically with 10 and 5% MCJBE ointments (MCJBEO), respectively. Result: The 10% MCJBE gave significantly (P < 0.05) highest percentage rate of wound contraction, shortest re-epithelialization and complete healing time when compared with 5% MCJBE and reference drug, framycetin sulfate. The extract of C. jagus showed significant (P < 0.05) concentration-dependent wound healing activity in incision, dead space and excision wound models. No contaminating microbial organism was isolated from wound sites of the rats dosed and treated with MCJBE throughout the study period. At day 7, post infliction of excision wound, histomorphological, and histochemical studies revealed more fibroblasts and Type 1 collagen deposits in wound site sections of rats treated with both 10 and 5% MCJBEO while those of the control showed more inflammatory cells and fewer Type 1 collagen deposits. At day 14 post infliction of excision wound, more epithelial regeneration with overlying keratin were seen in the histological sections of wounds of rats treated with both 10 and 5% MCJBEO, while histochemical study showed more Type 1 collagen deposits in wound site sections of rats in 10% MCJBEO treated group. Conclusion: This study established that methanolic C. jagus bulb extract

  6. Catalytic studies on a novel synthesis of methanol

    SciTech Connect

    Palekar, V.M.; Tierney, J.W.; Wender, I.

    1991-06-28

    Catalytic studies on a new method for methanol synthesis from CO and H{sub 2} in a slurry reactor are described. This reaction proceeds through the carbonylation of methanol to methyl formate in the liquid phase followed by hydrogenolysis of methyl formate to two molecules of methanol; the net result is the reaction of CO with H{sub 2} to give methanol. Moderate temperatures and pressures (100--160{degrees}C, 50--65 atm) are used. Reaction rates using mixed catalysts comprised of an alkali methoxide and Cu-chromite are presented. It seems likely that Cu-chromite maintains the activity of the alkali methoxide catalyst. A mixed catalyst comprised of potassium methoxide and Cu-chromite was found to be the most active under the reaction conditions used. Evidence is provided for an interaction between the alkali methoxide and Cu-chromite. 27 refs., 6 figs., 2 tabs.

  7. Entry and retention of methanol fuel in engine oil

    SciTech Connect

    Schwartz, S.E.; Smolenski, D.J.; Clark, S.L.

    1988-01-01

    To ensure that vehicles do not suffer adverse consequences when high-methanol-content fuel (M100 or M85) is used, it is important to understand the ways that the use of this fuel affects various vehicle systems. For that reason, some of the changes which occur in the engine oil when using methanol fuel were investigated. During a single cold start with an extended cranking time, as much as six percent fuel entered the engine oil. Over a 15-minute period, the lubricating medium changed from engine oil to an oil-methanol-water emulsion. With multiple cold starts followed by a five-minute trip and ambient temperatures near freezing, the oil contained 19 percent volatile contamination. In addition, the oil contained elevated levels of water, lead, iron, chromium, and aluminum. Efforts need to be directed toward reducing the adverse consequences of methanol fuel.

  8. Removal of sulfur contaminants in methanol for fuel cell applications

    SciTech Connect

    Lee, S.H.D.; Kumar, R.; Sederquist, R.

    1996-12-31

    Fuel cell power plants are being developed for transit bus and passenger car applications that use methanol as the on-board fuel. Commodity methanol by itself contains very little sulfur; however, it may occasionally be contaminated with up to about 1% diesel fuel or gasoline in current liquid-fuel distribution systems, leading to the presence of sulfur in the methanol fuel. This sulfur must be removed because of its deleterious effect on the reforming catalysts. International Fuel Cells has set the allowable sulfur limit in the methanol fuel at less than 1 ppm. The equilibrium adsorption isotherm and breakthrough data were used to assess the feasibility of developing a granular activated carbon adsorber for the removal of sulfur from transportation fuel cell systems.

  9. The Direct Methanol Liquid-Feed Fuel Cell

    NASA Technical Reports Server (NTRS)

    Halpert, Gerald

    1997-01-01

    Until the early 1990's the idea of a practical direct methanol fuel cell from transportation and other applications was just that, an idea. Several types of fuel cells that operate under near ambient conditions were under development.

  10. Detection of Methanol in a Class 0 Protostellar Disk

    NASA Technical Reports Server (NTRS)

    Langer, W.; Velusamy, T.; Goldsmith, P.

    1999-01-01

    We report the detection of emission from methanol in a compact source coincident with the position of the L1157 infrared source, which we attribute to molecules in the disk surrounding this young, class 0 protostellar object.

  11. Synergic effect of methanol and water on pine liquefaction.

    PubMed

    Zhao, Yun-Peng; Zhu, Wei-Wei; Wei, Xian-Yong; Fan, Xing; Cao, Jing-Pei; Dou, You-Quan; Zong, Zhi-Min; Zhao, Wei

    2013-08-01

    Pine liquefaction (PL) and re-liquefaction of its liquefaction residues in sub- and supercritical methanol, water or methanol/water mixed solvents (MWMSs) was investigated. The results show that isometric MWMS has the highest synergic effect on PL. Moreover, the total yield of bio-oil (BO) and conversion from pine and its residue both liquefied in the MWMS were obvious higher than those from PL in methanol (water) and re-liquefaction of its residue in water (methanol), suggesting that the interaction between the two solvents is responsible for synergic effect. This approach facilitates understanding the mechanism for biomass liquefaction in mixed solvents and developing efficient utilization process of biomass. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Detection of Methanol in a Class 0 Protostellar Disk

    NASA Technical Reports Server (NTRS)

    Langer, W.; Velusamy, T.; Goldsmith, P.

    1999-01-01

    We report the detection of emission from methanol in a compact source coincident with the position of the L1157 infrared source, which we attribute to molecules in the disk surrounding this young, class 0 protostellar object.

  13. Ultrasonic Spray-Assisted Solution-Based Vapor-Deposition of Aluminum Tris(8-hydroxyquinoline) Thin Films

    NASA Astrophysics Data System (ADS)

    Piao, Jinchun; Katori, Shigetaka; Ikenoue, Takumi; Fujita, Shizuo

    2011-02-01

    Aluminum tris(8-hydroxyquinoline) (Alq3) thin films were fabricated by a vapor-deposition technique from its methanol solution, that is, by the ultrasonic-assisted mist deposition technique. The application of high ultrasonic power to the Alq3-methanol mixture resulted in a stable and transparent solution. Mist particles formed by ultrasonic atomization of the solution were used as the source for vapor-deposition at the substrate temperature of 100-200 °C. Optical absorption and photoluminescence characteristics indicated the formation of Alq3 thin films. The results promise the formation of thin films of a variety of organic materials by the solution-based technique.

  14. Anti-spasmodic action of crude methanolic extract and a new compound isolated from the aerial parts of Myrsine africana

    PubMed Central

    2011-01-01

    Background Myrsine africana is an herbaceous plant that is traditionally used as appetizer and carminative. Locally, it is used for the treatment of pulmonary tuberculosis, rheumatism and diarrhea by healers. The aims of the current study were to screen the crude methanol extract obtained from the aerial parts (leaves and stem) of M. africana, for antispasmodic actions on isolated tissues and further to subject the ethyl acetate (EtOAc) fraction of plant to column chromatography for isolation of pure compounds. Methods The antispasmodic action of the crude methanol extract was measured on the spontaneous rabbit's jejunum preparations at concentration 0.01, 0.03, 0.1, 0.3, 1.0, 5.0 and 10.0 mg/ml. The crude extract was also applied, in similar concentrations, on KCl (80 mM) induced contractions to explain its possible mode of action. Results A new compound Myrsigenin was isolated from the EtOAc fraction of M. africana. The structure of the compound was identified with the help of 13C-NMR, 1H-NMR, HMBC, HMQC, NOESY and COSY. The plant crude methanol extract showed a significant antispasmodic action on rabbit jejunum and abolished the tissue contraction completely at concentration of 5.0 mg/ml. Conclusion The study concludes that the methanol crude extract of aerial parts of M. africana has antispasmodic action possibly through the calcium channel blocking mechanisms. A new compound Myrsigenin was isolated from the EtOAc fraction of the plant. PMID:21733176

  15. Coke formation in a zeolite crystal during the methanol-to-hydrocarbons reaction as studied with atom probe tomography

    DOE PAGES

    Schmidt, Joel E.; Poplawsky, Jonathan D.; Mazumder, Baishakhi; ...

    2016-08-03

    Understanding the formation of carbon deposits in zeolites is vital to developing new, superior materials for various applications, including oil and gas conversion processes. Herein, atom probe tomography (APT) has been used to spatially resolve the 3D compositional changes at the sub-nm length scale in a single zeolite ZSM-5 crystal, which has been partially deactivated by the methanol-to-hydrocarbons reaction using 13C-labeled methanol. The results reveal the formation of coke in agglomerates that span length scales from tens of nanometers to atomic clusters with a median size of 30–60 13C atoms. These clusters correlate with local increases in Brønsted acid sitemore » density, demonstrating that the formation of the first deactivating coke precursor molecules occurs in nanoscopic regions enriched in aluminum. Here, this nanoscale correlation underscores the importance of carefully engineering materials to suppress detrimental coke formation.« less

  16. Two-step method preparation of graphene without hydrogen on methanol pretreatment copper substrate by PECVD at low temperature

    NASA Astrophysics Data System (ADS)

    Han, Linzhi; Liu, JingJing; Zhao, Zhanxia; Chen, Shumin; Ma, Zhongquan; Zhao, Lei

    2016-10-01

    Plasma enhanced chemical vapor deposition (PECVD) is one effective method to prepare graphene at low temperature in a short time. However, the low temperature in PECVD could not provide substrate a proper state for large area and few layer graphene preparation. Herein, we propose a two-step method to grow graphene on Cu foils. In the first step, in order to acquire a smooth and oxide-free surface state, methanol was used as a reductant to pretreat Cu. In the second step, graphene films were prepared on Cu foils by PECVD using CH4 as carbon source with H2-free. Few-layer graphene sheets with diameter about 1 μm under low temperature (700 °C) and at a short time (10 min) on well pretreated Cu foils were successfully gotten. The effect of methanol pretreatment on graphene synthesis and the graphene growth mechanism on Cu substrate by PECVD are analyzed comprehensively.

  17. Coke formation in a zeolite crystal during the methanol-to-hydrocarbons reaction as studied with atom probe tomography

    SciTech Connect

    Schmidt, Joel E.; Poplawsky, Jonathan D.; Mazumder, Baishakhi; Attila, Özgün; Fu, Donglong; de Winter, D. A. Matthijs; Meirer, Florian; Bare, Simon R.; Weckhuysen, Bert M.

    2016-08-03

    Understanding the formation of carbon deposits in zeolites is vital to developing new, superior materials for various applications, including oil and gas conversion processes. Herein, atom probe tomography (APT) has been used to spatially resolve the 3D compositional changes at the sub-nm length scale in a single zeolite ZSM-5 crystal, which has been partially deactivated by the methanol-to-hydrocarbons reaction using 13C-labeled methanol. The results reveal the formation of coke in agglomerates that span length scales from tens of nanometers to atomic clusters with a median size of 30–60 13C atoms. These clusters correlate with local increases in Brønsted acid site density, demonstrating that the formation of the first deactivating coke precursor molecules occurs in nanoscopic regions enriched in aluminum. Here, this nanoscale correlation underscores the importance of carefully engineering materials to suppress detrimental coke formation.

  18. Serendipitous images of methanol in Comet Levy (1900 XX)

    NASA Technical Reports Server (NTRS)

    Hoban, Susan

    1993-01-01

    Reuter's (1992) model of the IR fluorescence of methanol is used to retrieve a methanol production rate of 3 +/- 1 x 10 exp 26/s and an abundance relative to water of about 0.1 percent. It is argued that calibration is of paramount importance and that a near-simultaneous spectrum is necessary for achieving a reliable estimate of the continuum underlying the emission feature.

  19. Hoechst Celanese picks Methanex as partner for methanol restart

    SciTech Connect

    Morris, G.D.L.

    1992-08-19

    Hoechst Celanese Chemical (Dallas) has chosen Methanex (Vancouver)-the former Ocelot Industries-as its partner for the restart of its long-mothballed 600,000-m.t./year methanol unit at Clear Lake, TX. The two firms are in the final stages of negotiations, and a formal announcement on the agreement could come as early as this week. Interest in methanol, has strengthened dramatically in the past couple of years, reflecting strong demand to feed production of fuel oxygenates.

  20. Ibn Sina plans giant methanol plant in Saudi Arabia

    SciTech Connect

    1994-12-14

    Following an announcement last week by Saudi Basic Industries Corp. that its Ar Razi joint venture plans to build an 850,000 m.t./year methanol plant at Al Jubail (CW December 7, p. 20) comes word that Sabic`s other domestic methanol production subsidiary, Ibn Sina, plans to add 1 million m.t./year of capacity. The new project will likely exceed $300 million.

  1. Effect of methanol on the biofiltration of n-hexane.

    PubMed

    Zehraoui, Abderrahman; Hassan, Ashraf Aly; Sorial, George A

    2012-06-15

    This study investigated the removal of recalcitrant compounds in the presence of a hydrophilic compound. n-Hexane is used as a model compound to represent hydrophobic compounds. Methanol has been introduced in mixture with n-hexane in order to increase the bioavailability of n-hexane in trickle-bed-air-biofilters (TBABs). The mixing ratios investigated were: 70% methanol:30% n-hexane, and 80% methanol:20% n-hexane by volume. n-Hexane loading rates (LRs) ranged from 0.9 to 13.2 g m(-3) h(-1). Methanol LRs varied from 4.6 to 64.5 g m(-3) h(-1) and from 2.3 to 45.2 g m(-3) h(-1) depending upon the mixing ratio used. Biofilter performance, effect of mixing ratios of methanol to n-hexane, removal profile along biofilter depth, COD/nitrogen consumption and CO(2) production were studied under continuous loading operation conditions. Results have shown that the degradation of n-hexane is significantly enhanced by the presence of methanol for n-hexane LRs less than 13.2 g m(-3) h(-1). For n-hexane LR greater than 13.2 g m(-3) h(-1), even though methanol had impacted n-hexane biodegradation, its removal efficiency was higher than our previous study for biodegradation of n-hexane alone, in presence of surfactant, or in presence of benzene. On the other hand, the degradation of methanol was not impacted by the presence of n-hexane.

  2. Methanol from wood waste : a technical and economic study

    Treesearch

    A. E. Hokanson; R. M. Rowell

    1977-01-01

    A methanol-from-wood waste facility having a capacity of 50 million gallons per year requires 1,500 ovendry tons (ODT) of wood waste per day. The yield of methanol from wood is about 38 percent, or about 100 gallons per ODT of wood. This yield is based on all process energy required coming from the wood waste. At a wood waste cost of $15/ODT, the selling price of...

  3. IRIS Toxicological Review of Methanol (Non-Cancer) ...

    EPA Pesticide Factsheets

    EPA is conducting a peer review and public comment of the scientific basis supporting the human health hazard and dose-response assessment of methanol (non-cancer) that when finalized will appear on the Integrated Risk Information System (IRIS) database. EPA is conducting a peer review of the scientific basis supporting the human health hazard and dose-response assessment of methanol (non-cancer) that will appear in the Integrated Risk Information System (IRIS) database.

  4. Molecular dynamics study of mass accommodation of methanol at liquid vapor interfaces of methanol/water binary solutions of various concentrations

    NASA Astrophysics Data System (ADS)

    Morita, Akihiro

    2003-06-01

    Molecular dynamics (MD) scattering simulation of methanol impinging to vapor-liquid interfaces of methanol/water mixture solutions is performed for various concentrations ranging from neat water to neat methanol. The present MD simulation predicts a mass accommodation coefficient α of methanol into neat water at 0 °C of almost unity, whereas an experimental value has been reported to be 0.056. One may conceive that the discrepancy may be attributed to the actual water surface being substantially covered by adsorbed methanol, but further MD simulation with various methanol concentrations invariantly yields an α of almost unity over the entire concentration range of the solution.

  5. Engineering electromagnetic metamaterials and methanol fuel cells

    NASA Astrophysics Data System (ADS)

    Yen, Tajen

    2005-07-01

    Electromagnetic metamaterials represent a group of artificial structures, whose dimensions are smaller than subwavelength. Due to electromagnetic metamaterials' collective response to the applied fields, they can exhibit unprecedented properties to fascinate researchers' eyes. For instance, artificial magnetism above terahertz frequencies and beyond, negative magnetic response, and artificial plasma lower than ultraviolet and visible frequencies. Our goal is to engineer those novel properties aforementioned at interested frequency regions and further optimize their performance. To fulfill this task, we developed exclusive micro/nano fabrication techniques to construct magnetic metamaterials (i.e., split-ring resonators and L-shaped resonators) and electric metamaterials (i.e., plasmonic wires) and also employed Taguchi method to study the optimal design of electromagnetic metamaterials. Moreover, by integrating magnetic and electric metamaterials, we have been pursuing to fabricate so-called negative index media---the Holy Grail enables not only to reverse conventional optical rules such as Snell's law, Doppler shift, and Cerenkov radiation, but also to smash the diffraction limit to realize the superlensing effect. In addition to electromagnetic metamaterials, in this dissertation we also successfully miniaturize silicon-based methanol fuel cells by means of micro-electrical-mechanical-system technique, which promise to provide an integrated micro power source with excellent performance. Our demonstrated power density and energy density are one of the highest in reported documents. Finally, based on the results of metamaterials and micro fuel cells, we intend to supply building blocks to complete an omnipotent device---a system with sensing, communication, computing, power, control, and actuation functions.

  6. Dietary Methanol Regulates Human Gene Activity

    PubMed Central

    Komarova, Tatiana V.; Sheshukova, Ekaterina V.; Kosorukov, Vyacheslav S.; Kiryanov, Gleb I.; Dorokhov, Yuri L.

    2014-01-01

    Methanol (MeOH) is considered to be a poison in humans because of the alcohol dehydrogenase (ADH)-mediated conversion of MeOH to formaldehyde (FA), which is toxic. Our recent genome-wide analysis of the mouse brain demonstrated that an increase in endogenous MeOH after ADH inhibition led to a significant increase in the plasma MeOH concentration and a modification of mRNA synthesis. These findings suggest endogenous MeOH involvement in homeostasis regulation by controlling mRNA levels. Here, we demonstrate directly that study volunteers displayed increasing concentrations of MeOH and FA in their blood plasma when consuming citrus pectin, ethanol and red wine. A microarray analysis of white blood cells (WBC) from volunteers after pectin intake showed various responses for 30 significantly differentially regulated mRNAs, most of which were somehow involved in the pathogenesis of Alzheimer's disease (AD). There was also a decreased synthesis of hemoglobin mRNA, HBA and HBB, the presence of which in WBC RNA was not a result of red blood cells contamination because erythrocyte-specific marker genes were not significantly expressed. A qRT-PCR analysis of volunteer WBCs after pectin and red wine intake confirmed the complicated relationship between the plasma MeOH content and the mRNA accumulation of both genes that were previously identified, namely, GAPDH and SNX27, and genes revealed in this study, including MME, SORL1, DDIT4, HBA and HBB. We hypothesized that human plasma MeOH has an impact on the WBC mRNA levels of genes involved in cell signaling. PMID:25033451

  7. Improved Flow-Field Structures for Direct Methanol Fuel Cells

    SciTech Connect

    Gurau, Bogdan

    2013-05-31

    The direct methanol fuel cell (DMFC) is ideal if high energy-density liquid fuels are required. Liquid fuels have advantages over compressed hydrogen including higher energy density and ease of handling. Although state-of-the-art DMFCs exhibit manageable degradation rates, excessive fuel crossover diminishes system energy and power density. Although use of dilute methanol mitigates crossover, the concomitant lowering of the gross fuel energy density (GFED) demands a complex balance-of-plant (BOP) that includes higher flow rates, external exhaust recirculation, etc. An alternative approach is redesign of the fuel delivery system to accommodate concentrated methanol. NuVant Systems Inc. (NuVant) will maximize the GFED by design and assembly of a DMFC that uses near neat methanol. The approach is to tune the diffusion of highly concentrated methanol (to the anode catalytic layer) to the back-diffusion of water formed at the cathode (i.e. in situ generation of dilute methanol at the anode layer). Crossover will be minimized without compromising the GFED by innovative integration of the anode flow-field and the diffusion layer. The integrated flow-field-diffusion-layers (IFDLs) will widen the current and potential DMFC operating ranges and enable the use of cathodes optimized for hydrogen-air fuel cells.

  8. Production of Methanol from Methane by Encapsulated Methylosinus sporium.

    PubMed

    Patel, Sanjay K S; Jeong, Jae-Hoon; Mehariya, Sanjeet; Otari, Sachin V; Madan, Bharat; Haw, Jung Rim; Lee, Jung-Kul; Zhang, Liaoyuan; Kim, In-Won

    2016-12-28

    Massive reserves of methane (CH₄) remain unexplored as a feedstock for the production of liquid fuels and chemicals, mainly because of the lack of economically suitable and sustainable strategies for selective oxidation of CH₄ to methanol. The present study demonstrates the bioconversion of CH₄ to methanol mediated by Type I methanotrophs, such as Methylomicrobium album and Methylomicrobium alcaliphilum. Furthermore, immobilization of a Type II methanotroph, Methylosinus sporium, was carried out using different encapsulation methods, employing sodium-alginate (Na-alginate) and silica gel. The encapsulated cells demonstrated higher stability for methanol production. The optimal pH, temperature, and agitation rate were determined to be pH 7.0, 30°C, and 175 rpm, respectively, using inoculum (1.5 mg of dry cell mass/ml) and 20% of CH₄ as a feed. Under these conditions, maximum methanol production (3.43 and 3.73 mM) by the encapsulated cells was recorded. Even after six cycles of reuse, the Na-alginate and silica gel encapsulated cells retained 61.8% and 51.6% of their initial efficiency for methanol production, respectively, in comparison with the efficiency of 11.5% observed in the case of free cells. These results suggest that encapsulation of methanotrophs is a promising approach to improve the stability of methanol production.

  9. Enhanced Methanol Production in Plants Provides Broad Spectrum Insect Resistance

    PubMed Central

    Dixit, Sameer; Upadhyay, Santosh Kumar; Singh, Harpal; Sidhu, Om Prakash; Verma, Praveen Chandra; K, Chandrashekar

    2013-01-01

    Plants naturally emit methanol as volatile organic compound. Methanol is toxic to insect pests; but the quantity produced by most of the plants is not enough to protect them against invading insect pests. In the present study, we demonstrated that the over-expression of pectin methylesterase, derived from Arabidopsis thaliana and Aspergillus niger, in transgenic tobacco plants enhances methanol production and resistance to polyphagous insect pests. Methanol content in the leaves of transgenic plants was measured using proton nuclear spectroscopy (1H NMR) and spectra showed up to 16 fold higher methanol as compared to control wild type (WT) plants. A maximum of 100 and 85% mortality in chewing insects Helicoverpa armigera and Spodoptera litura larvae was observed, respectively when fed on transgenic plants leaves. The surviving larvae showed less feeding, severe growth retardation and could not develop into pupae. In-planta bioassay on transgenic lines showed up to 99 and 75% reduction in the population multiplication of plant sap sucking pests Myzus persicae (aphid) and Bemisia tabaci (whitefly), respectively. Most of the phenotypic characters of transgenic plants were similar to WT plants. Confocal microscopy showed no deformities in cellular integrity, structure and density of stomata and trichomes of transgenic plants compared to WT. Pollen germination and tube formation was also not affected in transgenic plants. Cell wall enzyme transcript levels were comparable with WT. This study demonstrated for the first time that methanol emission can be utilized for imparting broad range insect resistance in plants. PMID:24223989

  10. Towards operating direct methanol fuel cells with highly concentrated fuel

    NASA Astrophysics Data System (ADS)

    Zhao, T. S.; Yang, W. W.; Chen, R.; Wu, Q. X.

    A significant advantage of direct methanol fuel cells (DMFCs) is the high specific energy of the liquid fuel, making it particularly suitable for portable and mobile applications. Nevertheless, conventional DMFCs have to be operated with excessively diluted methanol solutions to limit methanol crossover and the detrimental consequences. Operation with diluted methanol solutions significantly reduces the specific energy of the power pack and thereby prevents it from competing with advanced batteries. In view of this fact, there exists a need to improve conventional DMFC system designs, including membrane electrode assemblies and the subsystems for supplying/removing reactants/products, so that both the cell performance and the specific energy can be simultaneously maximized. This article provides a comprehensive review of past efforts on the optimization of DMFC systems that operate with concentrated methanol. Based on the discussion of the key issues associated with transport of the reactants/products, the strategies to manage the supply/removal of the reactants/products in DMFC operating with highly concentrated methanol are identified. With these strategies, the possible approaches to achieving the goal of concentrated fuel operation are then proposed. Past efforts in the management of the reactants/products for implementing each of the approaches are also summarized and reviewed.

  11. Methanol-powered cars get ready to hit the road

    SciTech Connect

    Moffat, A.S.

    1991-02-01

    In an effort to free the US from oil dependence on the Middle East and to reduce atmospheric pollution by automobile exhausts, the US automobile makers are about to take the historic step of commercial production of cars designed to run on methanol. Methanol has a higher octane rating (100) than gasoline (93-97), allows cars to run more efficiently, and offers more lively automobile performance. Some disadvantages of methanol powered cars are problems with cold starts; less energy per gallon of fuel would decrease the driving range of automobiles before refuel ling; production of more aldehydes, which exacerbate ozone and smog production and may be carcinogens as well; and higher costs ($300 to 500 more) than conventional vehicles. The uncertainty of availability of fuel has prompted automobile manufacturers to design current models of automobiles to be flexible fuel vehicles to run on mixtures of gasoline and methanol. Should the demand for methanol fuel increase, the availability would surely rise. The cost of methanol compares favorably with that of gasoline - $1.20 to 1.30 per gallon.

  12. [Effect of plant-associated methanolic bacteria on methane and methanol concentration dynamics in atmosphere of pressurized chamber].

    PubMed

    Berkovich, Iu A; Doronina, N V; Fedorov, D N; Mukhamedieva, L N; Mikos, K N; Krivobock, N M; Smolianin, V G; Smolianina, S O; Shanturin, N A

    2010-01-01

    Stability of Chinese cabbage crop colonization by methanolic bacteria Methylovorus mays, Methylomonas methanica and Methylosinus trichosporium inoculated using a space-applicable method was evaluated. Besides, trends of methane and methanol concentrations in the pressurized chamber with inoculated and uninoculated crops were calculated. Methylovorus mays and Methylosinus trichosporium were shown to establish more stable colonization as compared to Methylomonas methanica. Also, stable association of methanolic bacteria with plants reduced airborne methanol 75% faster owing to its uptake by bacteria. Therefore, inoculation of these microorganisms can be viewed as a promising method of controlling volatile pollutants in space vehicle atmosphere. Methane drop after 6-hour exposure to inoculated control and test crops was not significant.

  13. Treatment of Chronic Spontaneous Urticaria

    PubMed Central

    2012-01-01

    Chronic spontaneous urticaria is defined as persistent symptoms of urticaria for 6 weeks or more. It is associated with autoimmunity in approximately 45 percent of patients. Therapy is often difficult however the initial approach should employ high-dose non-sedating antihistamines; 4-6 tablets/day may be necessary. It has been shown that the response to 4 tablets/day exceeds 3, and exceeds 2, which exceeds 1. However the dose that corresponds to the maximal dose of first generation antihistamines (hydroxyzine, diphenhydramine) used previously, is 6/day. Yet over half the patients are refractory to antihistamines and other agents should be tried next. Whereas current guidelines (published) often add leukotriene antagonists and/or H2 receptor antogonists next, these are of little utility. Likewise drugs effective for urticarial vasculitis (colchicine, dapsone, sulfasalazine, hydroxychloroquine) are effective in a small percentage of patients and no study suggests that the response rate of any of them exceeds the 30% placebo responses seen in most double-blind, placebo controlled studies. The drugs that are effective for antihistamine-resistant chronic spontaneous urticaria are corticosteroids, cyclosporine, and Omalizumab. Use of steroids is limited by toxicity. If used at all, a dose of no more than 10 mg/day should be employed with a weekly reduction of 1 mg. The response rates to cyclosporine and Omalizumab are each close to 75%. Cyclosporine can be used effectively if care is taken to monitor blood pressure, urine protein, blood urea nitrogen, and creatinine, every 6 weeks. Omalizumab has the best profile in terms of efficacy/toxicity and, once approved by federal agencies for use in chronic spontaneous urticaria, a dramatic change in the treatment paradigm, whether associated with autoimmunity or not, is predicted. A phase 3 trial is currently in place. Refractoriness to both Omalizumab and cyclosporine is expected to be less than 5 percent of patients. Other

  14. Cardioprotective effect of spontaneous activity.

    PubMed

    Peltier, S; Novel-Chate, V; Malaisse, W J; Molnar, A; Leverve, X M; Favier, R

    2007-12-01

    In the perspective of giving a better understanding of the cardioprotective effects attributable to the tandem low caloric intake and training, Lou/C rats would be an interesting model since these animals exhibit spontaneously these two characteristics for months, without any dietary manipulations or stressor stimuli. No information was so far available on their cardiac function. Therefore, the aim of this pilot study was (i) to document cardiac function before and after ischemia in this strain, and (ii) to investigate whether spontaneous wheel-running activity can improve the ability of cardiac muscle to recover its function after an ischemic period. Cardiac mechanical and metabolic functions were measured in isolated Langendorff hearts from Wistar sedentary, Lou/C sedentary, and Lou/C wheel-running male rats submitted to a 20-min low-flow ischemia and 20-min reperfusion. In Lou/C sedentary rats, rate-pressure product, an index of cardiac work, was decreased before ischemia as compared to Wistar sedentary animals (- 24 %, p < 0.05). After ischemia, cardiac mechanical function recovery did not significantly differ between these two groups. Nevertheless, flux of non-oxidative glycolysis was lower before and after ischemia in Lou/C sedentary animals than in Wistar sedentary rats. In Lou/C rats, during normoxic perfusion, wheel-running activity significantly decreased heart rate (- 15 %), oxygen consumption (- 2.2 %) and cardiac efficiency (- 37 %), whereas coronary flow and flux of non-oxidative glycolysis were significantly increased (+ 15 % and + 263 %, respectively). After ischemia, recovery of cardiac mechanical function and cardiac efficiency were improved in Lou/C wheel-running rats versus Lou/C sedentary animals (p < 0.05). In conclusion, the impact of ischemia-reperfusion is similar between Lou/C- and Wistar sedentary rats. Spontaneous wheel-running activity decreases cardiac efficiency before ischemia and confers a protection against ischemia- and

  15. Assessment/Review of Methanol Technology and Utilization as a Fuel.

    DTIC Science & Technology

    1982-07-01

    employment of a selective zeolite molecular sieve catalyst which dehydrates methanol. The remaining methyl radicals combine to form a material similar...turbine ingestion and utilization inhalation Distribution Neat methanol Spark-ignition, Flame and handling, Compression-ignition, invisibility...ENVIRONMENT Methanol is a toxic substance that can enter the body through inhalation , ingestion, or absorption through the skin. Methanol has a low

  16. 26 CFR 48.4041-19 - Exemption for qualified methanol and ethanol fuel.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 16 2012-04-01 2012-04-01 false Exemption for qualified methanol and ethanol....4041-19 Exemption for qualified methanol and ethanol fuel. (a) In general. Under section 4041(b)(2... or use of qualified methanol or ethanol fuel. (b) Qualified methanol or ethanol fuel defined....

  17. 26 CFR 48.4041-19 - Exemption for qualified methanol and ethanol fuel.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 16 2011-04-01 2011-04-01 false Exemption for qualified methanol and ethanol....4041-19 Exemption for qualified methanol and ethanol fuel. (a) In general. Under section 4041(b)(2... or use of qualified methanol or ethanol fuel. (b) Qualified methanol or ethanol fuel defined....

  18. 26 CFR 48.4041-19 - Exemption for qualified methanol and ethanol fuel.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 16 2010-04-01 2010-04-01 true Exemption for qualified methanol and ethanol....4041-19 Exemption for qualified methanol and ethanol fuel. (a) In general. Under section 4041(b)(2... or use of qualified methanol or ethanol fuel. (b) Qualified methanol or ethanol fuel defined....

  19. 26 CFR 48.4041-19 - Exemption for qualified methanol and ethanol fuel.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 16 2013-04-01 2013-04-01 false Exemption for qualified methanol and ethanol....4041-19 Exemption for qualified methanol and ethanol fuel. (a) In general. Under section 4041(b)(2... or use of qualified methanol or ethanol fuel. (b) Qualified methanol or ethanol fuel defined....

  20. Spontaneous Pneumomediastinum Associated with Sex

    PubMed Central

    Flatman, Sam; Morrison, Edwin; Elahi, Maqsood

    2010-01-01

    We present a case of spontaneous pneumomediastinum (SPM) associated with sex. A 22-year-old lesbian with a history of asthma, cigarette and illicit drug smoking was diagnosed with a SPM after developing chest pain and dyspnoea in the context of performing oral sex. The main finding was subcutaneous emphysema involving the neck. SPM is an important differential diagnosis for chest pain in young people. It is a benign condition and diagnosis mainly limited to chest X-ray with increased incidence in asthmatics, smokers and drug addicts. PMID:22470723