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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 the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effects )

  6. 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.

  7. 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.

  8. 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. PMID:26070187

  9. 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.

  10. Spontaneous electrochemical processing in conventional organic solutions for iron ion removal and metal deposition

    NASA Astrophysics Data System (ADS)

    Sun, Jinghua

    2002-01-01

    In one part of this research, spontaneous electrochemical redox reactions in conventional organic solutions commonly used in solvent extraction were demonstrated. In these reactions, the more noble metal is reduced while the less noble metal dissolves simultaneously. This technique was successfully applied in metal recovery or impurity separation in laboratory tests using synthetic and commercially produced solutions. The second use of the process was in depositing metal seed layers on metallized wafers for use in chip manufacture. The patented process in the first application, called galvanic stripping, has been demonstrated on batch and continuous levels to separate iron from a sulfate medium using DEHPA. The use of zinc and steel scrap as reductants was evaluated. The reductant was found to be one of the most important components in the galvanic stripping process. The effects of other processing variables such as solution chemistry, reductant surface area, ferric ion concentration in the organic phase, agitation, and aqueous pH on iron recovery and efficiency were also evaluated. An experimental design with statistical analysis was utilized to optimize overall iron removal and process efficiency. The continuous test allowed the cycling of the organic and strip aqueous solutions and produced a concentrated iron sulfate strip solution containing ferrous ions in the range of 90 to 130 g/L. Based on the galvanic stripping principle a novel metal deposition technique was successfully applied for depositing seed layers on TiSiN and other metal films on Si wafers for subsequent electroless copper deposition as well as the deposition of gold onto a sputtered copper film. XPS measurements confirmed that the deposited particles or films were a pure metallic metal phase. The effects of various factors including the organic bath composition, reaction time, temperature and agitation on the deposit surface morphologies and the distribution of nuclei were investigated.

  11. Instrument for layer-by-layer deposition of catalyst layers directly on proton exchange membrane for direct methanol fuel cell.

    PubMed

    Wang, D; Wang, L; Liang, J; Liu, C

    2012-09-01

    A catalyst layer (CL) layer-by-layer (LbL) deposition instrument, consisting of an electrohydrodynamic atomization (EHDA) device and a proton exchange membrane (PEM) fixing device, has been developed. It has been used to deposit anode CL on Nafion membrane under different working distances of 4, 5, and 6 mm. The incorporation of EHDA LbL deposition allowed the generation of the CLs with different structures, where the higher working distance produced more porous CL structure. A catalyst-coated membrane (CCM) was also produced using this EHDA LbL deposition and PEM fixing device. It was observed that the catalyst has been uniformly coated on the Nafion membrane and the CCM presents an uniform surface feature. The performance of a single direct methanol fuel cell (DMFC) assembled with the deposited CCM at different working temperatures was analysed. The cell performance increased when the temperature rose. This instrument has the potential of being developed into a powerful device for controlling the deposition of CL of desired structures directly on PEM for DMFCs.

  12. Growth-surface-driven anisotropy and spontaneous layering in vapor-deposited alloy films

    NASA Astrophysics Data System (ADS)

    Shapiro, Alexander Leon

    Perpendicular magnetic anisotropy (PMA) developed on the growth surface has been studied in a number of vapor-deposited alloy film systems. Epitaxial (100), (110), (100) and polycrystalline CoXPt1-X ,CoX Pt1-X 1-YSiY, and NiXPt1-X alloy films have been deposited by co-evaporation over a range of growth temperatures from -50°C to 800°C. Growth induced PMA is reported in samples deposited at temperatures between 200--400°C. This PMA is closely correlated with evidence for clustering of the magnetic species. A model of the magnetic species clustered into thin platelets, with the interfaces between the platelets and the Pt matrix providing the source of PMA, is presented. Magnetic moment and Magneto-Optic Kerr Effect (MOKE) results support an interpretation of interfaces, like spontaneous incoherent multilayer fragments, perpendicular to the growth direction. Deposition rate experiments show that surface atomic mobility plays an important role in the development of platelets and PMA. Results from annealing experiments indicate that anisotropy and clustering are not bulk equilibrium phenomena, but are trapped into the growing surface. The presence of surface atomic mobility then at intermediate deposition temperatures along with a lack of bulk atomic mobility allow platelets on the surface to be trapped into the bulk by succeeding deposition layers. Studies of ternary Co-Pt-Si alloys, in which Si acts to slow surface atomic mobility, confirm that the mobility of adatoms on the surface is critical to the formation of platelet structures and PMA. The clustering and PMA found in Ni-Pt alloys remove magnetic interaction as a source of platelet formation, leading to surface segregation and reconstruction as likely to be critical to the development of PMA. The lack of clustering and anisotropy seen in (100) oriented NiPt films is correlated with a non-flat surface reconstruction which disrupts the formation of platelets.

  13. The importance of acid digestion of urine prior to spontaneous deposition of 210Po.

    PubMed

    Fellman, A; Ralston, L; Hickman, D; Ayres, L; Cohen, N; Spitz, H; Robinson, B

    1989-10-01

    Historically, radiochemical analysis of 210Po in urine has used spontaneous deposition of the nuclide directly from raw urine onto a suitable metal disc. Consequently, the urinary excretion fraction for Po in some current metabolic and dosimetric models is based on studies which inherently assume that metabolized (i.e., filtered out of the blood by the kidneys) 210Po is plated with the same efficiency as tracer 210Po which has been added to urine samples. Urine samples collected after intravenous administration of 210Po citrate to two species of nonhuman primates were divided and simultaneously analyzed via two methods: the historical procedure of plating 210Po from raw urine for one sample and a method which includes the addition of 208Po tracer and sample digestion with concentrated HNO3 prior to 210Po deposition for the other sample. A more significant amount of 210Po was consistently recovered when the urine was wet ashed then when it was not wet ashed. A temporal relationship was found to describe the change in the ratio of the deposition recoveries for the two methods. Possible mechanisms for this phenomenon and its dosimetric implications are discussed. PMID:2507478

  14. 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.

  15. 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.

  16. 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.

  17. 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

  18. 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.

  19. Atomic layer deposition of ZnO on Cu-nanoclusters for methanol synthesis

    SciTech Connect

    Zhang Ziyu; Patterson, Matthew; Ren Maoming; Wang Ying; Flake, John C.; Sprunger, Phillip T.; Kurtz, Richard L.

    2013-01-15

    The properties of ALD-grown ZnO thin films on Cu clusters supported on ZnO(1010) have been studied with scanning tunneling and scanning electron microscopy in combination with angle-resolved x-ray photoelectron spectroscopy. Deposition at room temperature of two monolayers of Cu on ZnO(1010) results in metallic Cu{sup 0} clusters {approx}8 nm wide by 1.4 nm high. Higher coverages of 15 ML results in a similar morphology, with slightly larger cluster sizes. Following air-exposure and ALD-growth of two cycles of ZnO, the Cu exhibits Cu{sup +} species characteristic of Cu{sub 2}O and the thin ZnO coating is hydroxylated. Electrochemical studies of ALD ZnO coatings on Cu suggest that they are more active for CO{sub 2} reduction.

  20. Methanol test

    MedlinePlus

    ... sources of methanol in the body include fruits, vegetables, and diet drinks that contain aspartame. Methanol is ... eat or drink it in toxic amounts. Methanol poisoning mainly affects the digestive system, nervous system, and ...

  1. One-pot synthesis of single-crystal Pt nanoplates uniformly deposited on reduced graphene oxide, and their high activity and stability on the electrocalalytic oxidation of methanol.

    PubMed

    Hao, Yanfei; Wang, Xudan; Shen, Jianfeng; Yuan, Junhua; Wang, Ai-Jun; Niu, Li; Huang, Shengtang

    2016-04-01

    We demonstrate a one-pot thermoreduction approach towards the preparation of single-crystal Pt nanoplates, which were uniformly deposited on the reduced graphene oxide (RGO) using polyvinylpyrrolidone (PVP) as a stabilizer. The size of Pt nanoplates can be tuned from 6.8 to 10.1 nm by controlling Pt loading. The as-prepared Pt/PVP/RGO catalysts show high stability and activity towards the methanol oxidation reaction (MOR). Their MOR current can reach up to 401 mA mg(-1) Pt and MOR current can maintain 89.4% of its initial value after 10 000 potential cycles.

  2. Encapsulation of photosensitizer into multilayer microcapsules by combination of spontaneous deposition and heat-induced shrinkage for photodynamic therapy.

    PubMed

    Han, Yuanyuan; Bu, Jing; Zhang, Yuying; Tong, Weijun; Gao, Changyou

    2012-10-01

    Annealing of PDADMAC/PSS multilayer microcapsules assembled on PSS-doped CaCO(3) particles at 80 °C for 30 min reduces their size dramatically from 6.9 ± 0.3 to 3.1 ± 0.5 µm. Methylene blue molecules are encapsulated by spontaneous deposition and post-annealing with a concentration of 22 mg · mL(-1), which is 1000 times higher than the feeding value. The unreleased MB molecules are retained stably for a long time, which are then protected by the capsules against reductive enzymes and keep their photodynamic activity. The viability of HeLa cells incubated with the MB-loaded capsules decreases sharply from ≈ 75 (dark cytotoxicity) to ≈ 20% after irradiation with a laser at 671 nm and 60 J · cm(-2) for 75 s.

  3. 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.

  4. Bimetallic Pt-Au nanocatalysts electrochemically deposited on graphene and their electrocatalytic characteristics towards oxygen reduction and methanol oxidation.

    PubMed

    Hu, Yaojuan; Zhang, Hua; Wu, Ping; Zhang, Hui; Zhou, Bo; Cai, Chenxin

    2011-03-01

    The burgeoning demand for clean and energy-efficient fuel cell system requires electrocatalysts to deliver greater activity and selectivity. Bimetallic catalysts have proven superior to single metal catalysts in this respect. This work reports the preparation, characterization, and electrocatalytic characteristics of a new bimetallic nanocatalyst. The catalyst, Pt-Au-graphene, was synthesized by electrodeposition of Pt-Au nanostructures on the surface of graphene sheets, and characterized by scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), X-ray powder diffraction (XRD), and voltammetry. The morphology and composition of the nanocatalyst can be easily controlled by adjusting the molar ratio between Pt and Au precursors. The electrocatalytic characteristics of the nanocatalysts for the oxygen reduction reaction (ORR) and the methanol oxidation reaction (MOR) were systematically investigated by cyclic voltammetry. The Pt-Au-graphene catalysts exhibits higher catalytic activity than Au-graphene and Pt-graphene catalysts for both the ORR and the MOR, and the highest activity is obtained at a Pt/Au molar ratio of 2:1. Moreover, graphene can significantly enhance the long-term stability of the nanocatalyst toward the MOR by effectively removing the accumulated carbonaceous species formed in the oxidation of methanol from the surface of the catalyst. Therefore, this work has demonstrated that a higher performance of ORR and the MOR could be realized at the Pt-Au-graphene electrocatalyst while Pt utilization also could be greatly diminished. This method may open a general approach for the morphology-controlled synthesis of bimetallic Pt-M nanocatalysts, which can be expected to have promising applications in fuel cells. PMID:21229152

  5. 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; Bobb-Semple, Dara; Tao, Jing; Tong, Xiao; Wang, Lei; Lewis, Crystal S.; Vuklmirovic, Miomir; Zhu, Yimei; et al

    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

  6. 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.

  7. [Methanol metabolism in plants].

    PubMed

    Stepanov, S S; Zolotar'ova, O K

    2011-01-01

    Methabolism of methanol in plant organisms is considered in the paper. Enzymes of consecutive oxidation of methanol and enzymes responsible for incorporation of carbon from methanol molecule to methyl groups of phospholipids, carboxylic acids and carbohydrates have been described. The peculiarity of plant organisms is in interaction of reactions of methanol transformation with pathways of photorespiration and C1-metabolism and in the capacity to use methanol carbon to form organic matter through photosynthesis. The inclusion of methanol metabolites in anabolic processes occurs at the level of formaldehyde and formiate. As a result, exogenous methanol at low concentrations can stimulate the photosynthetic efficiency of plants.

  8. 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.

  9. 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.

  10. 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

  11. 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. PMID:25756598

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. Spontaneous Recovery

    ERIC Educational Resources Information Center

    Rescorla, Robert A.

    2004-01-01

    Spontaneous recovery from extinction is one of the most basic phenomena of Pavlovian conditioning. Although it can be studied by using a variety of designs, some procedures are better than others for identifying the involvement of underlying learning processes. A wide range of different learning mechanisms has been suggested as being engaged by…

  20. 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)

  1. 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.

  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. 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. PMID:27652180

  4. 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.

  5. Spontaneous fission

    SciTech Connect

    Hoffman, D.C.

    1993-09-01

    The spontaneous fission (SF) of the heaviest actinides and the transactinides is of particular interest because of the dramatic changes in properties observed in the region of the heavy fermion isotopes and for still heavier elements. The existing experimental information on SF properties including half-life systematics, fragment kinetic-energy and mass-yield distributions, prompt neutron emission, and gamma emission will be reviewed. Possibility for extending studies of SF properties to other regions are considered and the potential for obtaining additional information about low-energy fission properties is discussed.

  6. 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.

  7. 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

  8. 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

  9. 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

  10. 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

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

    DOE PAGES

    Wohlfahrt, G.; Amelynck, C.; Ammann, C.; Arneth, A.; Bamberger, I.; Goldstein, A. H.; Gu, L.; Guenther, A.; Hansel, A.; Heinesch, B.; et al

    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

  12. 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

  13. Methanol in dark clouds.

    PubMed

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

    1988-01-01

    We report observations, for the first time, of the 2(0) - 1(0)A+ and E, 2(-1) - 1(-1) E, and 1(0) - 0(0)A+ lines of methanol (CH3OH) in three dark cold clouds, TMC1, L134N, and B335. The CH3OH emission is extended in these clouds and shows a complex velocity structure. Clear indications of non LTE excitation are observed in TMC 1. Estimated column densities are a few 10(13) cm-2. Although less abundant than formaldehyde (H2CO), methanol is almost an order of magnitude more abundant than acetaldehyde (CH3CHO), in these clouds. Dimethyl ether was searched for in L134N, to an upper limit of 4 10(12) cm-2 (3 sigma). Implications for dark cloud excitation and chemistry are discussed. A new, more accurate, rest frequency 96741.39(0.01) MHz is determined for the 2(0) - 1(0) A+ E line of methanol.

  14. 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.

  15. 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.

  16. Regional environmental impacts of methanol-fueled vehicles. Final report

    SciTech Connect

    Belian, T.; Morris, R.E.; Ligocki, M.P.; Whitten, G.Z.

    1991-12-27

    The objectives of the study were to obtain, through simulation modeling, preliminary estimates of the regional environmental impacts methanol-fueled vehicles and to estimate the sensitivity of the model to important parameters and assumptions that affect the calculation of the impacts. The regional environmental effects of the use of M85 fuel (85 percent methanol and 15 percent gasoline) and M100 (neat methanol) relative to gasoline (an indoline blend) were estimated using a Lagrangian (trajectory) acid deposition model. The Comprehensive Chemistry Acid Deposition Model (CCADM), contains a detailed treatment of gas-phase and aqueous-phase chemistry and associated mass transfer, but provides for a less comprehensive representation of advection and diffusion. Two different meteorological regimes were analyzed: clear sky conditions and cloudy skies with a rain event. The study also included a review of gas- and aqueous-phase chemistry, with particular emphasis on methanol. The CCADM chemical mechanism was updated to include state-of-the-science (as of 1990) gas- and aqueous-phase chemistry including methanol chemistry. The CCADM was then used to analyze the regional environmental impacts from the use of methanol fuels. In performing such an analysis it was necessary to make several assumptions. The sensitivity of the analysis was examined through a series of simulations that varied key input parameters within their ranges of uncertainty.

  17. Methanol simplifies gas processing

    SciTech Connect

    Minkkinen, A.; Jonchere, J.P.

    1997-12-31

    Recent development of a simple single solvent technology goes far to meet the complete gas processing needs. The use of methanol, as practiced in the IPFEXOL process, where it is used not only as a hydrate inhibitor and antifreeze agent but as an acid gas extraction solvent makes the complete gas processing scheme simple and probably the most cost effective as well. This paper presents several gas processing applications where water, hydrocarbon liquids and acid gases are removed from natural wellhead production gases. Water and hydrocarbon liquids removal is achieved to the extent necessary to make a pipeline transportable gas or meet downstream cryogenic processing demands. These are illustrated with recent applications of the IFPEX-1 process successfully operating today in North America and the Far East. A recent North Sea offshore project is highlighted showing the particular advantages in offshore applications. For the removal of water and hydrocarbon liquids together with a substantial quantity of not only CO{sub 2} but H{sub 2}S, the most complete methanol use scheme is presented. This is illustrated with the development of an advanced version of the IFPEX-2 process containing some innovative but simple equipment concepts which yields high pressure dry acid gases for reinjection or a high quality acid gas destined to Claus type sulfur recovery.

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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.

  3. Methanol related deaths in Edirne.

    PubMed

    Azmak, Derya

    2006-01-01

    In this retrospective autopsy study, a detailed analysis of methanol related deaths in Trakya region of Turkey is presented and departmental autopsy records, toxicology and histopathology results are analyzed. We found that methanol poisonings comprise 2.83% of all forensic autopsies (n:18), 88.8% of the cases were male, most of the victims were aged between 41 and 45. Blood methanol concentrations range widely from 55 to 479 mg per 100ml. Ethyl alcohol was detected in 44.4% of the cases. Most of the cases died in hospital and were poisoned through the consumption of alcoholic beverages from illicit sources and colognes. It is important for physicians to be aware of methanol poisoning symptoms and for forensic pathologists to obtain samples for toxicology during autopsies. Some preventative strategies including to routine control of the stores, to prevent the production of illegal alcoholic beverages, etc. should be developed.

  4. Methanol-induced neurotoxicity in pups exposed during lactation through mother: role of folic acid.

    PubMed

    Aziz, Moammir Hasan; Agrawal, Ashok Kumar; Adhami, Vaqar Mustafa; Ali, Mohammad M; Baig, Masroor A; Seth, Prahlad Kishore

    2002-01-01

    Role of folic acid on methanol-induced neurotoxicity was studied in pups at Postnatal Day (PND) 45 exposed to methanol (1%, 2% and 4%, v/v) during lactation through mothers maintained on folic acid-deficient (FD) and folic acid-sufficient (FS) diet. A gradual loss in the body weight gain was observed in the pups exposed to 2% and 4% methanol in the FD group, while FS group exhibited this alteration only at 4% exposure. The assessment of spontaneous locomotor activity (SLA) showing a significant increase in the distance travelled was observed in the 2% and 4% methanol-exposed groups in both the FS and FD animals when compared with their respective controls, but the effect was more marked in the FD group. A significant decrease in the conditioned avoidance response (CAR) was observed in pups exposed to 2% and 4% methanol in the FD group at PND 45. The results also suggest that disturbances in dopaminergic and cholinergic receptors were more pronounced in the FD group as compared to the FS group. A significant decrease in striatal dopamine levels was also observed in the FD group at 2% and 4% methanol exposure, while in the FS group, a significant decrease was exhibited only at 4% methanol exposure. An aberrant increase in the expression of Growth-Associated Protein (GAP-43), a neuron-specific growth-associated protein was observed in pups in the FD group exposed to 2% and 4% methanol, while an increase in the expression of GAP-43 in the FS group was found only at 4% methanol exposure in the hippocampal region as compared to their respective controls. Results suggests that methanol exposure during growth spurt period adversely affects the developing brain, the effect being more pronounced in FD rats as compared to FS rats, suggesting a possible role of folic acid in methanol-induced neurotoxicity.

  5. Methanol-induced neurotoxicity in pups exposed during lactation through mother: role of folic acid.

    PubMed

    Aziz, Moammir Hasan; Agrawal, Ashok Kumar; Adhami, Vaqar Mustafa; Ali, Mohammad M; Baig, Masroor A; Seth, Prahlad Kishore

    2002-01-01

    Role of folic acid on methanol-induced neurotoxicity was studied in pups at Postnatal Day (PND) 45 exposed to methanol (1%, 2% and 4%, v/v) during lactation through mothers maintained on folic acid-deficient (FD) and folic acid-sufficient (FS) diet. A gradual loss in the body weight gain was observed in the pups exposed to 2% and 4% methanol in the FD group, while FS group exhibited this alteration only at 4% exposure. The assessment of spontaneous locomotor activity (SLA) showing a significant increase in the distance travelled was observed in the 2% and 4% methanol-exposed groups in both the FS and FD animals when compared with their respective controls, but the effect was more marked in the FD group. A significant decrease in the conditioned avoidance response (CAR) was observed in pups exposed to 2% and 4% methanol in the FD group at PND 45. The results also suggest that disturbances in dopaminergic and cholinergic receptors were more pronounced in the FD group as compared to the FS group. A significant decrease in striatal dopamine levels was also observed in the FD group at 2% and 4% methanol exposure, while in the FS group, a significant decrease was exhibited only at 4% methanol exposure. An aberrant increase in the expression of Growth-Associated Protein (GAP-43), a neuron-specific growth-associated protein was observed in pups in the FD group exposed to 2% and 4% methanol, while an increase in the expression of GAP-43 in the FS group was found only at 4% methanol exposure in the hippocampal region as compared to their respective controls. Results suggests that methanol exposure during growth spurt period adversely affects the developing brain, the effect being more pronounced in FD rats as compared to FS rats, suggesting a possible role of folic acid in methanol-induced neurotoxicity. PMID:12127898

  6. Antihypertensive and vasodilator effects of methanolic and aqueous extracts of Tribulus terrestris in rats.

    PubMed

    Phillips, Oludotun A; Mathew, Koyippalli T; Oriowo, Mabayoje A

    2006-04-01

    The effects of methanolic and aqueous extracts of Tribulus terrestris on rat blood pressure (BP) and the perfused mesenteric vascular bed were investigated. The extracts dose-dependently reduced BP in spontaneously hypertensive rats (SHRs) with the aqueous fraction being more potent than the methanolic fraction at all doses tested. In vitro, the methanolic but not aqueous extract produced a dose-dependent increase in perfusion pressure of the mesenteric vascular bed. When perfusion pressure was raised with phenylephrine (10(-5) M), the aqueous extract produced a dose-dependent reduction in perfusion pressure at all doses. A low dose of the methanolic extract produced a vasoconstrictor effect while higher doses produced dose-dependent reduction in perfusion pressure. L-NAME (10(-4) M) significantly reduced but did not abolish vasodilation induced by the extracts. Vasodilator responses to aqueous and methanolic fractions were significantly reduced in preparations where perfusion pressure was raised with KCl (60 mM). A combination of KCl and L-NAME abolished the vasodilator responses induced by the extracts. It was concluded that methanolic and aqueous extracts of Tribulus terrestris possess significant antihypertensive activity in spontaneously hypertensive rats. The antihypertensive effects appeared to result from a direct arterial smooth muscle relaxation possibly involving nitric oxide release and membrane hyperpolarization.

  7. 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.

  8. 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

  9. 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.

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

    PubMed

    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

  11. Spontaneous pneumothorax during pregnancy.

    PubMed

    Gorospe, Luis; Puente, Susana; Madrid, Carmen; Novo, Susana; Gil-Alonso, José L; Guntiñas, Alicia

    2002-05-01

    Spontaneous pneumothorax complicating pregnancy is rare. Only 41 cases have been previously published. We describe a case of spontaneous pneumothorax successfully treated with tube thoracostomy during the 38th week of pregnancy. Under epidural anesthesia, the patient had vaginal delivery of a healthy male infant 36 hours after tube thoracostomy.

  12. 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.

  13. Directional spontaneous emission enhancement in hyperbolic metamaterials

    NASA Astrophysics Data System (ADS)

    Sreekanth, K. V.; Biaglow, T.; Strangi, G.

    2013-10-01

    In this paper, we experimentally demonstrate the control of spontaneous emission enhancement in multilayered Au/Al2O3 hyperbolic metamaterials (HMMs). The hyperbolic dispersion of the Au/Al2O3 multilayers at optical frequencies is confirmed by using effective medium theory, and then the results are validated by experiments performed through variable angle spectroscopic ellipsometry. The modification of spontaneous emission enhancement is observed when the emission wavelengths of different chromophores deposited on top of the multilayer are tuned from the elliptical to hyperbolic spectral region of the HMM. The simulation results further support the modification of spontaneous emission enhancement in designed HMM. This proposed concept and methodology promises potential applications in areas such as single photon sources and biosensing.

  14. 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.

  15. 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.

  16. 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.

  17. Spontaneous cholecystocutaneous abscess.

    PubMed

    Metsemakers, W J; Quanten, I; Vanhoenacker, F; Spiessens, T

    2010-01-01

    Spontaneous cholecystocutaneous abscesses or fistulae are rare complications of neglected biliary calculous disease which have become extremely rare during the last decades. We report a case of spontaneous cholecystocutaneous abscess in a 69-year-old male who presented with a mass in the right subcostal region.The diagnosis was made by CT scan with multiplanar reformating. Treatment consisted of incision and drainage of the abdominal wall abscess followed by cholecystectomy in a one-stage protocol.

  18. 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.

  19. 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.

  20. Withanolide artifacts formed in methanol.

    PubMed

    Cao, Cong-Mei; Zhang, Huaping; Gallagher, Robert J; Timmermann, Barbara N

    2013-11-22

    Methanol solutions of the main withanolides (6-8) naturally present in Physalis longifolia yielded five artificial withanolides (1-5), including three new compounds (1-3). Withanolides 1 and 2 were identified as intramolecular Michael addition derivatives, while withanolides 3-5 were the result of intermolecular Michael addition. A comprehensive literature investigation was conducted to identify potential withanolide Michael addition artifacts isolated from Solanaceous species to date.

  1. Studies on methanol - oxidizing yeast. III. Enzyme.

    PubMed

    Volfová, O

    1975-01-01

    Oxidation of methanol, formaldehyde and formic acid was studied in cells and cell-free extract of the yeast Candida boidinii No. 11Bh. Methanol oxidase, an enzyme oxidizing methanol to formaldehyde, was formed inducibly after the addition of methanol to yeast cells. The oxidation of methanol by cell-free extract was dependent on the presence of oxygen and independent of any addition of nicotine-amide nucleotides. Temperature optimum for the oxidation of methanol to formaldehyde was 35 degrees C, pH optimum was 8.5. The Km for methanol was 0.8mM. The cell-free extract exhibited a broad substrate specificity towards primary alcohols (C1--C6). The activity of methanol oxidase was not inhibited by 1mM KCN, EDTA or monoiodoacetic acid. The strongest inhibitory action was exerted by p-chloromercuribenzoate. Both the cells and the cell-free extract contained catalase which participated in the oxidation of methanol to formaldehyde; the enzyme was constitutively formed by the yeast. The pH optimum for the degradation of H2O2 was in the same range as the optimum for methanol oxidation, viz. at 8.5. Catalase was more resistant to high pH than methanol oxidase. The cell-free extract contained also GSH-dependent NAD-formaldehyde dehydrogenase with Km = 0.29mM and NAD-formate dehydrogenase with Km = 55mM. PMID:240764

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. Propane Clathrate Hydrate Formation Accelerated by Methanol.

    PubMed

    Amtawong, Jaruwan; Guo, Jin; Hale, Jared S; Sengupta, Suvrajit; Fleischer, Everly B; Martin, Rachel W; Janda, Kenneth C

    2016-07-01

    The role of methanol as both an inhibitor and a catalyst for the formation of clathrate hydrates (CHs) has been a topic of intense study. We report a new quantitative study of the kinetics of propane CH formation at 253 K from the reaction of propane gas with <75 μm ice particles that have been doped with varying amounts of methanol. We find that methanol significantly accelerates the formation reaction with quite small doping quantities. Even for only 1 methanol molecule per 10 000 water molecules, the maximum uptake rate of propane into CHs is enhanced and the initiation pressure is reduced. These results enable more efficient production of CHs for gas storage. This remarkable acceleration of the CH formation reaction by small quantities of methanol may place constraints on the mechanism of the inhibition effect observed under other conditions, usually employing much larger quantities of methanol. PMID:27275862

  11. A novel process for methanol synthesis

    SciTech Connect

    Tierney, J.W.; Wender, I.

    1992-01-28

    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 of methanol to methyl formate taking place in a non-equilibrium region in the vicinity of the copper chromite surface, and the hydrogenolysis of methyl formate to methanol taking place on the surface of the copper chromite. The synergism between the two catalysts enhances the rate of methanol formation. In this quarter, we tested several copper chromites (with different surface areas and stabilizing agents) on the rate of methanol synthesis. It seems likely that pore diffusion limitations control the hydrogenolysis reaction since the rate of methanol formation is proportional to the square root of the copper chromite surface area. Elemental analyses using Inductively Coupled Plasma analysis and pore size distribution analysis of copper chromite were carried out.

  12. Asymptomatic blood methanol in emergency room patients.

    PubMed

    Wargotz, E S; Werner, M

    1987-06-01

    Over a four-month period, methanol was found in the blood of 18 patients among 687 sequential emergency room admissions screened for alcohols by gas chromatography. In the patients with positive results, blood ethanol ranged from 6 to 570 mg/dL (1.3-123.7 mmol/L), blood methanol from 2.3 to 4.0 mg/dL (0.72-1.25 mmol/L). Methanol exposure during preparation of the sampling site or in the course of specimen handling, ingestion of denatured alcohol, as well as methanol production from the metabolism of aspartame are ruled out as causes for these findings. The authors conclude that endogenous methanol production is the probable major cause, while methanol as a fermentation congener may be a contributory minor cause.

  13. 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.

  14. 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.

  15. 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.

  16. A modified Nafion membrane with in situ polymerized polypyrrole for the direct methanol fuel cell

    NASA Astrophysics Data System (ADS)

    Smit, M. A.; Ocampo, A. L.; Espinosa-Medina, M. A.; Sebastián, P. J.

    Nafion membranes were modified by the in situ electrodeposition of polypyrrole inside the membrane pores and on the anode side only, in order to prevent the cross-over of methanol in the direct methanol fuel cell (DMFC). Pretreated Nafion membranes were first immersed in 0.1 M sulphuric acid containing the pyrrole monomer and subsequently removed from this solution and placed in a two-electrode solid-state electrochemical cell, where the polypyrrole was formed galvanostatically. The modified membranes were studied in terms of morphology, electrochemical characteristics and methanol permeability. FTIR and SEM confirmed the presence of the polypyrrole on the anode side of the Nafion membrane. SEM shows the polymer to be present both on the membrane surface and inside the membrane pores. It was found to be deposited as small grains, with two distinct sizes, the smallest particles have a diameter of around 100 nm, while the larger particles have diameters of around 700 nm. Methanol permeability was determined electrochemically and was shown to be effectively reduced. Cyclic voltammetry was performed in sulphuric acid, in pure methanol and in 50 vol.% methanol. The untreated Nafion membrane showed CV curves which were similar in all electrolytes with electroactivity only at the extreme ends of the curve. The Nafion/Ppy membrane showed typical polypyrrole curves, with current densities lowest in sulphuric acid, and highest in the 50 vol.% methanol, respectively. For the methanol containing electrolytes, an additional oxidative peak appears in the CV, which may be related to electrocatalytic activity of the polypyrrole for methanol oxidation.

  17. Negligible photodesorption of methanol ice and active photon-induced desorption of its irradiation products

    NASA Astrophysics Data System (ADS)

    Cruz-Diaz, G. A.; Martín-Doménech, R.; Muñoz Caro, G. M.; Chen, Y.-J.

    2016-07-01

    Context. Methanol is a common component of interstellar and circumstellar ice mantles and is often used as an evolution indicator in star-forming regions. The observations of gas-phase methanol in the interiors of dense molecular clouds at temperatures as low as 10 K suggest that non-thermal ice desorption must be active. Ice photodesorption has been proposed to explain the abundances of gas-phase molecules toward the coldest regions. Aims: Laboratory experiments were performed to investigate the potential photodesorption of methanol toward the coldest regions. Methods: Solid methanol was deposited at 8 K and UV-irradiated at various temperatures starting from 8 K. The irradiation of the ice was monitored by means of infrared spectroscopy and the molecules in the gas phase were detected using quadrupole mass spectroscopy. Fully deuterated methanol was used for confirmation of the results. Results: The photodesorption of methanol to the gas phase was not observed in the mass spectra at different irradiation temperatures. We estimate an upper limit of 3 × 10-5 molecules per incident photon. On the other hand, photon-induced desorption of the main photoproducts was clearly observed. Conclusions: The negligible photodesorption of methanol could be explained by the ability of UV-photons in the 114-180 nm (10.87-6.88 eV) range to dissociate this molecule efficiently. Therefore, the presence of gas-phase methanol in the absence of thermal desorption remains unexplained. On the other hand, we find CH4 to desorb from irradiated methanol ice, which was not found to desorb in the pure CH4 ice irradiation experiments.

  18. Bioinduced Room-Temperature Methanol Reforming.

    PubMed

    Heim, Leo E; Thiel, Daniel; Gedig, Christian; Deska, Jan; Prechtl, Martin H G

    2015-08-24

    Imitating nature's approach in nucleophile-activated formaldehyde dehydrogenation, air-stable ruthenium complexes proved to be exquisite catalysts for the dehydrogenation of formaldehyde hydrate as well as for the transfer hydrogenation to unsaturated organic substrates at loadings as low as 0.5 mol %. Concatenation of the chemical hydrogen-fixation route with an oxidase-mediated activation of methanol gives an artificial methylotrophic in vitro metabolism providing methanol-derived reduction equivalents for synthetic hydrogenation purposes. Moreover, for the first time methanol reforming at room temperature was achieved on the basis of this bioinduced dehydrogenation path delivering hydrogen gas from aqueous methanol.

  19. Methanol-Resistant Oxygen-Reduction Catalysts for Direct Methanol Fuel Cells

    NASA Astrophysics Data System (ADS)

    Shukla, A. K.; Raman, R. K.

    2003-08-01

    Methanol oxidation in the cathode compartment of the fuel cell, which occurs during the oxygen-reduction reaction on Pt-based cathodes, constitutes a significant performance loss in the direct methanol fuel cells. Over the past decade, four types of methanol-resistant oxygen-reduction catalysts have been developed to circumvent this problem. Among these, transition-metal chalcogenides, and in particular RuSe, have shown effective selectivity to oxygen-reduction reaction in the presence of methanol. These catalysts not only can enhance the performance of the conventional direct methanol fuel cells but also could provide a route to develop mixed-reactants direct methanol fuel cells, which could be highly cost-effective in comparison with the conventional direct methanol fuel cells. This article is a brief update on the preparation, characterization, and implications of methanol-resistant oxygen-reduction catalysts.

  20. Breakdown in vapors of alcohols: methanol and ethanol

    NASA Astrophysics Data System (ADS)

    Petrovic, Zoran Lj.; Sivos, Jelena; Skoro, Nikola; Maric, Dragana; Malovic, Gordana

    2014-10-01

    Breakdown data for vapors of the two simplest alcohols - methanol and ethanol - are presented. The breakdown is achieved between plan-parallel electrodes, where cathode is made of copper and anode is a thin film of platinum deposited on quartz window. Diameter of electrodes is 5.4 cm and electrode gap 1.1 cm. We compare breakdown voltages (Paschen curves) for methyl and ethyl alcohol in the pressure range 0.1--2 Torr. In both vapors, the pressure is kept well below the vapor pressure, to prevent formation of liquid droplets. For each point of Paschen curves corresponding axial profiles of emission are recorded by ICCD camera in visual part of the spectra. Axial intensity distributions reveal important processes of excitation. Both vapors show strong emission peak near the cathode at all pd values covered by measurements, which indicates that excitation by ions and fast neutrals play important role in the discharge. Preliminary spectrally resolved measurements of the discharge structure with optical filters show that dominantly emission comes from CH band at 431 nm. There is a very low intensity of H α emission detected in ethanol vapor at high E/N, while it is much stronger in methanol even at lower E/N. It is interesting to note that H α emission in methanol exhibits exponential increase of intensity from the cathode to the anode, so it comes mainly from excitation by electrons, not heavy particles. Supported by MESTD Projects ON171037 and III41011.

  1. SnS2 Thin Film Deposition by Spray Pyrolysis

    NASA Astrophysics Data System (ADS)

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

    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.

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

    PubMed Central

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

    2016-01-01

    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. PMID:27301420

  3. Density functional theory study of O-H and C-H bond scission of methanol catalyzed by a chemisorbed oxygen layer on Cu(111)

    NASA Astrophysics Data System (ADS)

    Li, Jonathan; Zhou, Guangwen

    2016-04-01

    Using the density-functional theory within the generalized gradient approximation, we have studied the partial oxidation of methanol on a Cu(111) surface covered with a chemisorbed oxygen layer that resembles a Cu2O layer. Adsorption energies and geometries were computed for methanol, methoxy, hydroxymethyl and formaldehyde on both clean Cu(111) and Cu2O/Cu(111) and electronic structures were computed for the reaction intermediates on Cu2O/Cu(111). We also calculated the energy barrier for partial oxidation of methanol to formaldehyde on Cu2O/Cu(111). These results show that the Cu2O monolayer slightly lowers the stability of each of the surface adsorbates and the oxygen strongly promotes hydrogen dissociation by lowering the energy barrier of methanol decomposition and causing the spontaneous dissociation of methanol into methoxy.

  4. Spontaneous periodic hypothermia.

    PubMed

    Kloos, R T

    1995-09-01

    Spontaneous periodic hypothermia is a rare syndrome of recurrent, centrally mediated hypothermia without an identifiable systemic cause or brain lesion. Most patients defend a temporarily lowered temperature "set point" during episodes of hypothermia, despite manifesting many well-known systemic consequences of core temperature hypothermia. No case of death directly attributable to an episode of spontaneous periodic hypothermia has been reported, although many of the serious systemic effects of hypothermia have been documented in these cases, so it is not unlikely that death may occur. The syndrome's cause, and that of Shapiro syndrome, remains unknown. Pharmacologic trials to date have been only modestly successful. Anticonvulsant agents, clonidine, and cyproheptadine appear the most likely to succeed, with cyproheptadine being a reasonable first choice. Given that the term "spontaneous periodic hypothermia" describes a syndrome, and not a pathophysiologic mechanism, it is likely to encompass a common eventuality, arrived at via several different pathways. One can postulate mechanisms such as structural abnormalities, trauma, infection, irritation, and degeneration involving strategic locations which create a focus for epileptic or other periodic dysfunction whose scope involves the centers for thermoregulation. The existence of 2 distinct, oppositional thermoregulatory centers would allow for speculation of similar mechanisms accounting for cases of both periodic hypo- and hyperthermia (61). Postmortem data regarding the hypothalamic and surrounding areas from future cases of Shapiro syndrome and spontaneous periodic hypothermia would be of great interest. Further, more sensitive in vivo testing methods are clearly needed. The role of PET or single photon emission computed tomography (SPECT) with technetium 99m-labeled hexamethylpropylene amine oxime (Tc 99m HMPAO) performed acutely during an episode remains to be characterized (64, 103, 105). The term

  5. 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...

  6. 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.

  7. 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

  8. 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

  9. [Spontaneous bilateral Petit hernia].

    PubMed

    Fontoura, Rodrigo Dias; Araújo, Emerson Silveira de; Oliveira, Gustavo Alves de; Sarmenghi Filho, Deolindo; Kalil, Mitre

    2011-01-01

    Petit's lumbar hernia is an uncommon defect of the posterior abdominal wall that represents less than 1% of all abdominal wall hernias. It is more often unilateral and founded in young females, rarely containing a real herniated sac. There are two different approaches to repair: laparoscopy and open surgery. The goal of this article is to report one case of spontaneous bilateral lumbar Petit's hernia treated with open surgery.

  10. Spontaneously generated radioactive nanoparticles in the environment

    NASA Astrophysics Data System (ADS)

    Marlow, William H.; Cheng, Yung-Sung

    2003-04-01

    For almost 100 years, and perhaps longer, observers have detected spontaneous dispersal of radioactivity from macroscopic quantities of radioactive materials with the first published observations reported in 1910. In the 1960"s and later, radioactivity was observed to migrate through HEPA filters de-spite their well-established filtration characteristics. In measurements of ground water, radioactivity has been found to disperse from its original location of deposition in soil, despite the size, insolubility, and resistance to chemical reactions of the radioactive particles originally deposited. Similarly, measurements of the uptake of these materials in lung tissue and studies of their solubility in simulated biological fluids showed the solubility to be related to the radioactivity of the materials. In numerous practical examples, the migration and deposition of radioactivity affects work and operational practices. Despite this long and varied history indicating the importance of self-dispersal of radioactive materials, no measurements had ever been reported of the materials which were actually dispersed until recently and the results are quite surprising, suggesting a well-defined process creating discrete nanoparticle fractions. This paper will review the history of the observations of spontaneous dispersal of radioactivity and close with a description of the first measure-ments of the dispersed nanoparticles and suggestions of the physical processes involved in their formation.

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. [Recurrent spontaneous abortions].

    PubMed

    Salat-Baroux, J

    1988-01-01

    The process of fertilization in humans, is remarkably inefficient. Spontaneous abortion is estimated to be between 15 and 20% of all clinical pregnancies, and the early spontaneous abortion rate is closer to 30-50% of fertilized ova. Not all authors agree on the definition of "recurrent spontaneous abortion" (RSA), so the frequency of repeated pregnancy wastage is difficult to determine; from empirically derived data, it has been estimated to range between 0.4 and 0.8%. Because of the various etiologies of RSA, their association in determining an abortive event, it is difficult to evaluate their exact incidence. Moreover, their is no prospective study on this subject, so it is advisable to distinguish between the admitted causes, the likely factors, and the etiologies to be evaluated. In the first group, the congenital or acquired müllerian anomalies (especially the septate uterus), represent about 25% of the RSA, but a lot of problems concerning the physiopathology are still debated, even if the rate of pregnancies after surgery ranges around 50% in certain series. On the other hand, the genetic factors, identified especially with the banding technique, are undeniable: however, although the rate of chromosomal aberrations in the offspring (Monosomy X, Trisony 16, Triploidy) is very high (50 to 60% of spontaneous abortions in the first trimester of pregnancy), when couples with usual abortions are subjected to karyotypic analysis, genetic anomalies (especially translocations) are been noted in only 6.2% of the women and 2.6% of the men. In the second group, the infective factors (chlamydiae, toxoplasma and mycoplasma) are difficult to analyse since the serology is not sufficient without a real proof of an endometrial colonization. Among the endocrinological causes, the classical luteal phase deficiency remains a subject of controversy (estimated between 3 and 30%) not only for the establishment of the diagnosis, but also for the efficiency of progesterone

  17. Spontaneous acalculous gallbladder perforation

    PubMed Central

    Sheridan, David; Qazi, Almas; Lisa, Selina; Vashisht, Rajiv

    2014-01-01

    An 86-year-old woman, 4 days post-operative following a right-sided Austin-Moore arthroplasty, reported abdominal pain around a known umbilical hernia and became increasingly confused. A diagnosis of incarcerated umbilical hernia was made. At surgery, on entering the peritoneal cavity, bile was immediately noted. The operation was converted to a laparotomy and a perforation was noted in the gallbladder. An open cholecystectomy was performed. Macroscopically the gallbladder was perforated in multiple places, was thin walled and did not contain gallstones. This case demonstrates the difficulty in diagnosing an apparently spontaneous gallbladder perforation in a cognitively frail patient. PMID:25293685

  18. 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.

  19. Spontaneous acalculous gallbladder perforation.

    PubMed

    Sheridan, David; Qazi, Almas; Lisa, Selina; Vashisht, Rajiv

    2014-10-07

    An 86-year-old woman, 4 days post-operative following a right-sided Austin-Moore arthroplasty, reported abdominal pain around a known umbilical hernia and became increasingly confused. A diagnosis of incarcerated umbilical hernia was made. At surgery, on entering the peritoneal cavity, bile was immediately noted. The operation was converted to a laparotomy and a perforation was noted in the gallbladder. An open cholecystectomy was performed. Macroscopically the gallbladder was perforated in multiple places, was thin walled and did not contain gallstones. This case demonstrates the difficulty in diagnosing an apparently spontaneous gallbladder perforation in a cognitively frail patient.

  20. [Spontaneous course of depression].

    PubMed

    Azorin, J M

    1995-03-01

    The study of the spontaneous course of depressions nowadays comes up against a number of obstacles. The most important of these is the necessity of using untreated cases, which virtually forces the contemporary researcher to refer to studies performed in the pretherapeutic era, if conclusions are not be drawn only from classical descriptions. Unfortunately, these studies are marked by the absence of strict diagnostic criteria, the heterogeneity of patients included in them, the lack of preciseness of evaluations and the primitive statistical methods used. They are concerned essentially with the duration of depressive phases and the factors which influence it. Among these latter are regularly found age, sex, the number of episodes, the duration of the preceding symptom-free interval, the severity and semiology of the attack, heredity, mode of onset, level of intelligence, the presence or absence of associated pathology and the presence or absence of hospitalisation. Chronicization of depression and the factors concerned with it have also been the object of several studies. A small number of investigations compare the course of the illness in untreated populations. The study of the spontaneous course of depression evidences the necessity of having consensus definitions, and may serve as a basis for a better comprehension of the process of cure and of the real impact of therapies designed to treat depression.

  1. 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.

  2. 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.

  3. 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.

  4. 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)

  5. 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.

  6. Esterification of acrylic acid with methanol

    SciTech Connect

    Chubarov, G.A.; Danov, S.M.; Logutov, V.I.; Obmelyukhina, T.N.

    1984-01-01

    The esterification of acrylic acid with methanol in the absence of catalysis by strong mineral acids has been studied. The esterification rate was estimated from the amount of methyl acrylate formed at the end of a definite time, and the reaction rate was found to be first order with respect to methanol and second order with respect to acrylic acid. Mathematical relationships in good agreement with experimental data were derived from the results of the kinetic studies.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. Spontaneous soft tissue hematomas.

    PubMed

    Dohan, A; Darnige, L; Sapoval, M; Pellerin, O

    2015-01-01

    Spontaneous muscle hematomas are a common and serious complication of anticoagulant treatment. The incidence of this event has increased along with the rise in the number of patients receiving anticoagulants. Radiological management is both diagnostic and interventional. Computed tomography angiography (CTA) is the main tool for the detection of hemorrhage to obtain a positive, topographic diagnosis and determine the severity. Detection of an active leak of contrast material during the arterial or venous phase is an indication for the use of arterial embolization. In addition, the interventional radiological procedure can be planned with CTA. Arterial embolization of the pedicles that are the source of the bleeding is an effective technique. The rate of technical and clinical success is 90% and 86%, respectively. PMID:26066549

  16. Spontaneous Iliac Vein Rupture

    PubMed Central

    Kim, Dae Hwan; Park, Hyung Sub; Lee, Taeseung

    2015-01-01

    Spontaneous iliac vein rupture (SIVR) is a rare entity, which usually occurs without a precipitating factor, but can be a life-threatening emergency often requiring an emergency operation. This is a case report of SIVR in a 62-year-old female who presented to the emergency room with left leg swelling. Workup with contrast-enhanced computed tomography revealed a left leg deep vein thrombosis with May-Thurner syndrome and a hematoma in the pelvic cavity without definite evidence of arterial bleeding. She was managed conservatively without surgical intervention, and also underwent inferior vena cava filter insertion and subsequent anticoagulation therapy for pulmonary thromboembolism. This case shows that SIVR can be successfully managed with close monitoring and conservative management, and anticoagulation may be safely applied despite the patient presenting with venous bleeding. PMID:26217647

  17. Spontaneous Coronary Artery Dissection.

    PubMed

    Tweet, Marysia S; Gulati, Rajiv; Hayes, Sharonne N

    2016-07-01

    Spontaneous coronary artery dissection is an important etiology of nonatherosclerotic acute coronary syndrome, myocardial infarction, and sudden death. Innovations in the catheterization laboratory including optical coherence tomography and intravascular ultrasound have enhanced the ability to visualize intimal disruption and intramural hematoma associated with SCAD. Formerly considered "rare," these technological advances and heightened awareness suggest that SCAD is more prevalent than prior estimates. SCAD is associated with female sex, young age, extreme emotional stress, or extreme exertion, pregnancy, and fibromuscular dysplasia. The clinical characteristics and management strategies of SCAD patients are different than for atherosclerotic heart disease and deserve specific consideration. This review will highlight recent discoveries about SCAD as well as describe current efforts to elucidate remaining gaps in knowledge.

  18. Spontaneous Coronary Artery Dissection.

    PubMed

    Tweet, Marysia S; Gulati, Rajiv; Hayes, Sharonne N

    2016-07-01

    Spontaneous coronary artery dissection is an important etiology of nonatherosclerotic acute coronary syndrome, myocardial infarction, and sudden death. Innovations in the catheterization laboratory including optical coherence tomography and intravascular ultrasound have enhanced the ability to visualize intimal disruption and intramural hematoma associated with SCAD. Formerly considered "rare," these technological advances and heightened awareness suggest that SCAD is more prevalent than prior estimates. SCAD is associated with female sex, young age, extreme emotional stress, or extreme exertion, pregnancy, and fibromuscular dysplasia. The clinical characteristics and management strategies of SCAD patients are different than for atherosclerotic heart disease and deserve specific consideration. This review will highlight recent discoveries about SCAD as well as describe current efforts to elucidate remaining gaps in knowledge. PMID:27216840

  19. Pharmacokinetics of methanol and formate in female cynomolgus monkeys exposed to methanol vapors.

    PubMed

    Medinsky, M A; Dorman, D C; Bond, J A; Moss, O R; Janszen, D B; Everitt, J I

    1997-06-01

    The 1990 Clean Air Act Amendments contain mandates for reduced automotive emissions and add new requirements for the use of alternative fuels such as methanol to reduce certain automotive pollutants. Methanol is acutely toxic in humans at relatively low doses, and the potential for exposure to methanol will be increased if it is used in automotive fuel. Formate is the metabolite responsible for neurotoxic effects of acute methanol exposure. Since formate metabolism is dependent on folate, potentially sensitive folate-deficient subpopulations, such as pregnant women, may accumulate formate and be at higher risk from low-level methanol exposure. Our objective was to determine the pharmacokinetics of 14C-methanol and 14C-formate in normal and folate-deficient monkeys after exposure to 14C-methanol vapors at environmentally relevant concentrations: below the threshold limit value (TLV), at the TLV of 200 parts per million (ppm), and above the TLV. Four normal adult female cynomolgus monkeys were individually anesthetized with isoflurane, and each was exposed by endotracheal intubation to 10, 45, 200, or 900 ppm 14C-methanol for 2 hours. Concentrations of the inhaled and exhaled 14C-methanol, blood concentrations of 14C-methanol and 14C-formate, exhaled 14C-carbon dioxide (14CO2), and respiratory parameters were measured during exposure. After exposure, 14C-methanol and 14CO2 exhaled, 14C-methanol and 14C-formate excreted in urine, and 14C-methanol and 14C-formate in blood were quantified. The amounts of exhaled 14C-methanol and 14CO2, blood concentrations of 14C-methanol and 14C-formate, and 14C-methanol and 14C-formate excreted in urine were linearly related to methanol exposure concentration. For all exposures, blood concentrations of 14C-methanol-derived formate were 10 to 1000 times lower than endogenous blood formate concentrations (100 to 200 mM) reported for monkeys and were several orders of magnitude lower than levels of formate known to be toxic. Since the

  20. 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. PMID:19827801

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Neuropharmcological potential of methanolic extract and a triterpene isolated from Madhuca longifolia L leaves in mice.

    PubMed

    Inganakal, Triveni S; Ahmed, Md Liyakhat; Swamy, Paramjyothi

    2012-12-01

    The methanolic extract of M. longifolia (MLME) and a compound a triterpene, derivative of madhucic acid (dMA) isolated from the leaves of M. longifolia, were investigated for their possible neuropharmacological activities in mice using phenobarbitone induced sleeping time, spontaneous motor activity, marble burying test and Eddy's hot plate method. LD50 for MLME and dMA were 100 and 10 mg/kg of body weight, respectively. Both MLME and dMA (10 mg/kg and 2 mg/kg oral route respectively) exhibited significant increase in phenobarbitone induced sleeping time, greater reduction in spontaneous motor activity and marble burying activity, confirming their sedative nature. Both MLME and dMA also exhibited considerable antinociceptive activity in experimental animals. The results suggest that both MLME and dMA have CNS depressant activity in mice.

  8. 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

  9. Spontaneous subgaleal aerocele.

    PubMed

    Ibe, M O N; Onu, D O; Igwe, N N

    2014-01-01

    Apart from reporting about a case of spontaneous subgaleal aerocele this paper looks at the possible causes and management also. A 35-year-old Igbo-Nigerian female, about 4 weeks post-natal, with a 10-month old steadily and gradually enlarging mass around the back of her head, including both temporal regions was referred to us. Plain skull radiographs showed air in this mass. Needle puncture produced air leading to immediate and complete flattening of the lesion. A few hours after this procedure while still in the hospital premises, she had generalized convulsions, for which she was hospitalized and treated. With no further attacks, her request for discharge the following day was granted. At the next visit, 7 days later, there was a re-accumulation, which was treated the same way as previously and with the same result. She has not reported back since then, though she was advised to visit us again in 7 day-time. This lesion should be considered when masses on the head are presented. Our health institutions should have adequate investigative facilities.

  10. 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.

  11. 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.

  12. 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.

  13. Dynamic signature of molecular association in methanol.

    PubMed

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

    2016-07-01

    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. PMID:27394112

  14. Intracranial hemorrhage associated with methanol intoxication.

    PubMed

    Sebe, Ahmet; Satar, Salim; Uzun, Belkan; Topal, Metin; Yesilagac, Hasan; Avci, Andakkan

    2006-12-01

    Methanol is a common component of gasoline, antifreeze, washer fluid, perfume, household cleaners and various other industrial products. Acute methanol poisoning produces severe metabolic acidosis, serious neurologic sequelae and rarely imaging findings. In this paper, we describe a 35-year-old man with methanol intoxication who was in a comatose stage. Computed tomography (CT) showed widespread brain edema and hemorrhages localized in the supratentorial region of the temporal lobe, nearly 3 x 1 cm in a crescent shape, in the white matter surrounding the capsula externa and extending to the periventricular white matter and occipital lobes. Temporal lobe hemorrhage in our patient might also have been due to the effect of heparinization during hemodialysis, metabolic and lactic acidosis, or formate.

  15. 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.

  16. 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.

  17. 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.

  18. Dynamic signature of molecular association in methanol

    NASA Astrophysics Data System (ADS)

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

    2016-07-01

    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.

  19. 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.

  20. 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

  1. 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.

  2. 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.

  3. Quantifying global terrestrial methanol emissions using observations from the TES satellite sensor

    NASA Astrophysics Data System (ADS)

    Wells, K. C.; Millet, D. B.; Cady-Pereira, K. E.; Shephard, M. W.; Henze, D. K.; Bousserez, N.; Apel, E. C.; de Gouw, J.; Warneke, C.; Singh, H. B.

    2014-03-01

    We employ new global space-based measurements of atmospheric methanol from the Tropospheric Emission Spectrometer (TES) with the adjoint of the GEOS-Chem chemical transport model to quantify terrestrial emissions of methanol to the atmosphere. Biogenic methanol emissions in the model are based on version 2.1 of the Model of Emissions of Gases and Aerosols from Nature (MEGANv2.1), using leaf area data from NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) and GEOS-5 assimilated meteorological fields. We first carry out a pseudo observation test to validate the overall approach, and find that the TES sampling density is sufficient to accurately quantify regional- to continental-scale methanol emissions using this method. A global inversion of two years of TES data yields an optimized annual global surface flux of 122 Tg yr-1 (including biogenic, pyrogenic, and anthropogenic sources), an increase of 60% from the a priori global flux of 76 Tg yr-1. Global terrestrial methanol emissions are thus nearly 25% those of isoprene (~540 Tg yr-1), and are comparable to the combined emissions of all anthropogenic volatile organic compounds (~100-200 Tg yr-1). Our a posteriori terrestrial methanol source leads to a strong improvement of the simulation relative to an ensemble of airborne observations, and corroborates two other recent top-down estimates (114-120 Tg yr-1) derived using in situ and space-based measurements. Inversions testing the sensitivity of optimized fluxes to model errors in OH, dry deposition, and oceanic uptake of methanol, as well as to the assumed a priori constraint, lead to global fluxes ranging from 118 to 126 Tg yr-1. The TES data imply a relatively modest revision of model emissions over most of the tropics, but a significant upward revision in midlatitudes, particularly over Europe and North America. We interpret the inversion results in terms of specific source types using the methanol : CO correlations measured by TES, and find that

  4. 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.

  5. 37 GHz Methanol Masers : Horsemen of the Apocalypse for the Class II Methanol Maser Phase?

    NASA Astrophysics Data System (ADS)

    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.

  6. Spontaneous resolution of subfoveal perfluorocarbon

    PubMed Central

    Oellers, Patrick; Charkoudian, Leon D; Hahn, Paul

    2015-01-01

    Perfluorocarbon liquids (PFCL) have transformed the surgical approach to complex retinal detachments, but their use can be complicated by subretinal retention. Migration of peripherally located subretinal PFCL towards the fovea is well established, but spontaneous resolution of subfoveal PFCL without surgical evacuation or displacement has rarely been described. We present a case of a large single retained subfoveal PFCL droplet following vitrectomy with membrane peeling, inferior relaxing retinectomy, and silicone oil tamponade that demonstrated spontaneous resolution 3 weeks postoperatively, with subsequent anatomic and visual improvement. No residual subretinal PFCL was noted, and we hypothesize that the PFCL droplet spontaneously extruded through a transient hole created in the thinned retina overlying the droplet, which subsequently closed spontaneously. Further understanding of the mechanisms of PFCL migration and resolution may facilitate improved treatments for this complication. PMID:25834389

  7. Possible fasciocidal activity of methanol extract of Dregea volubilis leaves.

    PubMed

    Hossain, Emdad; Chandra, Goutam; Nandy, Anadi P; Gupta, Jayanta Kumar; Mandal, Subhash C

    2013-10-01

    In eastern and southern part of India Dregea volubilis (Family Asclepediaceae) is widely used as anthelmintic in traditional system of medicine. The present study was conducted to evaluate the fasciocidal activity of the methanol extract of D. volubilis leaves (MEDV) and to observe the drug's effect on organisms through scanning electron microscopic (SEM) study. Live parasites (Trematode: Fasciola gigantica) were collected in 0.9% phosphate-buffered saline from the bile ducts of buffalo. Those were incubated in the said media at 37 ± 1 °C either as control, or with MEDV at 5, 10, 25, 50 and 100 mg/ml as test groups or with albendazole at 10mg/ml as standard group. The efficacy of the extract was determined on the basis of paralysis (temporary loss of spontaneous movement of the organisms) and/or death of the liver flukes. Death was confirmed when the organisms lost their motility permanently and their motility could not be revived even when vigorously shaken or dipped in warm water. MEDV at all concentration effectively paralyzed first and then killed the liver flukes (p < 0.001). Maximum fasciocidal activity was found with concentration of 100 mg/ml at 38.83 ± 3.41 min. Through SEM study, severe damages were observed in both the suckers as well as on the tegumental surfaces of the treated liver flukes. The study confirmed the fasciocidal activity of the MEDV.

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

    DOEpatents

    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.

  9. 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.

  10. 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

  11. 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.

  12. A Search for Class I Methanol Masers

    NASA Astrophysics Data System (ADS)

    Pratap, P.

    2001-12-01

    Class I masers are thought to be associated with outflow activity from young stars and are easily explained with a collisional pumping model. However, masers have been found in regions where there is no apparent star formation or outflow activity. These masers could be probing a very early stage of star formation. Most searches for Class I masers have been done toward regions of known star formation. Such searches are biased as they would not find masers offset by distances greater than the telescope beam. The MIT Haystack Observatory Class I methanol maser survey is a project conducted by undergraduate students using the Haystack 37-m telescope. Each student maps a chosen molecular cloud and searches for maser emission. Once the student project is complete the data becomes part of a database of methanol masers. This collaborative observing strategy results in an unbiased search for new sites of methanol maser activity. Currently five clouds have been mapped and several new sites of methanol maser activity have been discovered. This project is funded by the Divisions of Astronomy and Undergraduate Education of the National Science Foundation.

  13. 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.

  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)

    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.

  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. 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.

  17. HYDROGEN BONDING IN THE METHANOL DIMER

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  18. 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.

  19. 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.

  20. 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.

  1. Metacridamide B methanol-d4 monosolvate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  2. 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

  3. 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

  4. 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).

  5. 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

  6. Conversion of crude methanol to gasoline with extraction

    SciTech Connect

    Harandi, M.N.; Owen, H.; Smyth, S.C.

    1987-11-24

    A continuous process for converting crude methanol to gasoline boiling range hydrocarbons in a catalytic reaction zone with a crystalline acid zeolite catalyst at elevated temperature and pressure is described comprising the steps of: (a) contacting a crude methanol feedstock containing a minor amount of water with a liquid hydrocarbon extraction stream under extraction conditions favorable to selective extraction of the methanol, thereby providing an extract liquid stream rich in methanol and an aqueous raffinate stream lean in methanol; (b) charging the extracted methanol substantially free of water to the reaction zone under process conditions to convert substantially all methanol to hydrocarbons; (c) cooling reaction effluent to recover aqueous liquid by-product stream, gas rich in C/sub 2/ + hydrocarbons, liquid rich in C/sub 3/-C/sub 4/ and C/sub 5/ + hydrocarbons; and (d) contacting crude methanol feedstock with at least a portion of the liquid hydrocarbons employed as extraction liquid.

  7. 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.

  8. 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.

  9. Mechanisms of spontaneous human cancers.

    PubMed

    Venitt, S

    1996-05-01

    The causes of much of human cancer remain obscure. The fraction that is spontaneous is unknown and cannot be calculated until all known external causes have been accounted for. This is not a feasible proposition. However, there is substantial evidence that about 80% of human cancer could be avoided by eliminating tobacco consumption; by dietary changes; by reducing infection with certain viruses, bacteria, and parasitic worms; and, in white populations, by avoiding sunburn. Alcohol, occupational and medical carcinogens, and certain patterns of reproductive behavior also contribute to the cancer burden. Cancers that cannot be attributed to these causes, and for which no other causes can be found, could be considered spontaneous and to arise from endogenous processes. Epidemiological evidence suggests that spontaneous and induced cancers share the same mechanism. Cancer is a genetic disorder of somatic cells. An accumulation of mutant genes that control the cell cycle, maintain genomic stability, and mediate apoptosis is central to carcinogenesis. Spontaneous mutation may cause spontaneous cancer. Endogenous causes of mutation include depurination and depyrimidation of DNA; proofreading and mismatch errors during DNA replication; deamination of 5-methylcytosine to produce C to T base pair substitutions; and damage to DNA and its replication imposed by products of metabolism (notably oxidative damage caused by oxygen free radicals). Deficiencies in cellular defense mechanisms may also provoke spontaneous mutation. These include defective DNA excision-repair; low levels of antioxidants, antioxidant enzymes, and nucleophiles that trap DNA-reactive electrophiles; and enzymes that conjugate nucleophiles with DNA-damaging electrophiles. Mechanisms underlying many of those cellular defenses are under genetic control. Thus, germ line mutations or polymorphisms of genes that govern them may also contribute to spontaneous cancer.

  10. 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…

  11. 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

  12. 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

  13. [Three cases of spontaneous pneumomediastinum].

    PubMed

    Kobayashi, Kashin; Tachikawa, Soichi; Horiguchi, Takahiko; Kondo, Rieko; Shiga, Mamoru; Hirose, Masahiro; Sasaki, Yasushi; Torigoe, Hiroshi

    2006-04-01

    We encountered 3 male patients with spontaneous pneumomediastinum. The patients were a 16-year old and a 17-year old and a 24-year old. Predisposing episodes for the development of spontaneous pneumomediastinum could be identified in all 3 patients: throwing a ball during a baseball game in 1, lifting a heavy load during work in 2. However, they were healthy and suddenly developed symptoms in the absence of any underlying disease. The presenting complaint was chest pain in all 3 patients. Chest X-ray films and chest CT images revealed pneumomediastinum. A diagnosis of spontaneous pneumomediastinum was made based on chest X-ray films and chest CT images. After conservative treatment, all 3 patients recovered.

  14. 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.

  15. 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.

  16. 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.

  17. Platinum Nickel Nanowires as Methanol Oxidation Electrocatalysts

    DOE PAGES

    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 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

  18. 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.

  19. Towards oil independence through renewable methanol chemistry.

    PubMed

    Olah, George A

    2013-01-01

    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.

  20. Spontaneous Fission: A Kinetic Approach

    SciTech Connect

    Bonasera, A.; Iwamoto, A.; Bonasera, A.

    1997-01-01

    We present an attempt towards the many-body description of spontaneous fission based on the semiclassical Vlasov equation and the Feynman path integral method. We define suitable collective variables from the Vlasov solution and use the imaginary time technique for the dynamics below the Coulomb barrier. We demonstrate (1) the stability of the Vlasov solution, (2) the ability of this model to calculate the basic features of the whole spontaneous fission process, (3) the sensitivity of the dynamics below the barrier to the mean field potential, and (4) the important role of collective excitations and of particle emission during the fission process. {copyright} {ital 1997} {ital The American Physical Society}

  1. Spontaneous rupture of the ureter.

    PubMed

    Eken, Alper; Akbas, Tugana; Arpaci, Taner

    2015-02-01

    Spontaneous rupture of the ureter is a very rare condition and usually results from ureteral obstruction by a calculus. Only theoretical mechanisms have been proposed and no possible explanation has yet been reported in the literature. Intravenous contrast-enhanced computed tomography is the most informative study with high sensitivity. Treatment should be individualised, and depends on the state of the patient. Minimally invasive endourological procedures with double-J catheter placement and percutaneous drainage offer excellent results. Conservative management with analgesics and antibiotic coverage may be an alternative to surgery. Herein, we present a case of spontaneous rupture of the proximal ureter with no evidence of an underlying pathological condition.

  2. Spontaneous cervical and mediastinal emphysema.

    PubMed

    Parker, G S; Mosborg, D A; Foley, R W; Stiernberg, C M

    1990-09-01

    Subcutaneous cervical emphysema often appears as a result of surgery or trauma. However, when it occurs spontaneously, the patient may present with clinically impressive and dramatic features. The etiology is related to the rupture of terminal alveoli and dissection of air along the pulmonary vasculature. Exercise may contribute to the process by increases in intrathoracic pressure. Six cases of spontaneous cervical emphysema, all related to SCUBA diving training at a Naval facility, were recently seen at our institution. Proper management entails having a high index of suspicion for diagnosis, and then being able to identify potentially life-threatening complications.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Possible thermochemical cycle based on methanol. [Tetramethylphosphine

    SciTech Connect

    Mason, C.F.V.

    1982-01-01

    The production of hydrogen from methanol is of particular interest since the two reactions: CH/sub 4/ + H/sub 2/O + CO + 3H/sub 2/ and CO + 2H/sub 2/ = CH/sub 3/OH are individually well known industrial processes. Thus, if a method can be found to obtain the overall reaction: CH/sub 3/OH = CH/sub 4/ + 1/2 O/sub 2/ then, in total, a cyclic water splitting process is complete for which much of the industrial development is already known. A possible method is through the use of trimethylphosphine. This reacts with methanol to form a salt, tetramethyl phosphonium hydroxide: CH/sub 3/OH + (CH/sub 3/)/sub 3/P = (CH/sub 3/)/sub 4/POH. Tetramethylphosphonium hydroxide gives methane and trimethylphosphine oxide very readily: (CH/sub 3/)/sub 4/POH = CH/sub 4/ + (CH/sub 3/)/sub 3/PO. When anhydrous takes place readily at room temperature, but in the presence of water, the rate is retarded. In summary, the overall reaction can be written as: CH/sub 3/OH + (CH/sub 3/)/sub 3/P = CH/sub 4/ + (CH/sub 3/)/sub 3/PO. Thus, provided a way of removing oxygen from trimethylphosphine oxide can be found, (CH/sub 3/)/sub 3/PO = (CH/sub 3/)/sub 3/P + 1/2 O/sub 2/ is a simple method of converting methanol to methane and oxygen.

  8. Enzymatic conversion of carbon dioxide to methanol: Enhanced methanol production in silica sol-gel matrices

    SciTech Connect

    Obert, R.; Dave, B.C.

    1999-12-29

    Strategies for effective conversion of atmospheric CO{sub 2} to methanol offer promising new technologies not only for recycling of the greenhouse gas but also for an efficient production of fuel alternatives. Partial hydrogenation of carbon dioxide has been accomplished by means of heterogeneous catalysis, electrocatalysis, and photocatalysis. Oxide-based catalysts are predominantly used for industrial fixation of carbon dioxide. A unique approach in this direction involves the use of enzymes as catalysts for conversion of carbon dioxide to methanol. The use of enzymes is particularly appealing since it provides a facile low-temperature route for generation of methanol directly from gaseous carbon dioxide. The authors report an enzymatically coupled sequential reduction of carbon dioxide to methanol by using a series of reactions catalyzed by three different dehydrogenases. Overall, the process involves an initial reduction of CO{sub 2} to formate catalyzed by formate dehydrogenase (F{sub ate}DH), followed by reduction of formate to formaldehyde by formaldehyde dehydrogenase (F{sub ald}DH), and finally formaldehyde is reduced to methanol by alcohol dehydrogenase (ADH). In this process, reduced nicotinamide adenine dinucleotide (NADH) acts as a terminal electron donor for each dehydrogenase-catalyzed reduction.

  9. 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. PMID:27644241

  10. 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.

  11. 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.

  12. 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. PMID:27254727

  13. 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

  14. Chemical pleurodesis for spontaneous pneumothorax.

    PubMed

    How, Cheng-Hung; Hsu, Hsao-Hsun; Chen, Jin-Shing

    2013-12-01

    Pneumothorax is defined as the presence of air in the pleural cavity. Spontaneous pneumothorax, occurring without antecedent traumatic or iatrogenic cause, is sub-divided into primary and secondary. The severity of pneumothorax could be varied from asymptomatic to hemodynamically compromised. Optimal management of this benign disease has been a matter of debate. In addition to evacuating air from the pleural space by simple aspiration or chest tube drainage, the management of spontaneous pneumothorax also focused on ceasing air leakage and preventing recurrences by surgical intervention or chemical pleurodesis. Chemical pleurodesis is a procedure to achieve symphysis between the two layers of pleura by sclerosing agents. In the current practice guidelines, chemical pleurodesis is reserved for patients unable or unwilling to receive surgery. Recent researches have found that chemical pleurodesis is also safe and effective in preventing pneumothorax recurrence in patients with the first episode of spontaneous pneumothorax or after thoracoscopic surgery and treating persistent air leakage after thoracoscopic surgery. In this article we aimed at exploring the role of chemical pleurodesis for spontaneous pneumothorax, including ceasing air leakage and preventing recurrence. The indications, choice of sclerosants, safety, effects, and possible side effects or complications of chemical pleurodesis are also reviewed here.

  15. Smoking habits and spontaneous abortion.

    PubMed

    Sandahl, B

    1989-04-01

    Smoking habits have been compared in three samples of pregnancies: (1) spontaneous abortions (n = 610); (2) induced abortions (n = 800); and (3) deliveries (n = 1337). The variables studied were, besides smoking habits, day of LMP, outcome of earlier pregnancies, maternal age, and, for the delivery sample, also diagnoses of mother and child, gestational length, sex, and birthweight. A statistical analysis of the association between smoking and the risk of having a spontaneous abortion was made. The comparisons were made with all types of intra-uterine pregnancies but spontaneous abortions, e.g., deliveries and induced abortions. The effects and consequences of that are discussed. The smoking rates according to pregnancy outcome differ among the samples. In the induced abortion sample 58% smoked compared with 50% in the spontaneous abortion sample and 44% in the delivery sample. The well-known effect of smoking on gestational length and birthweight was shown. No significant effect of smoking on the miscarriage risk was seen. The only trend was the opposite. Possible explanations for this are discussed.

  16. 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…

  17. 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…

  18. 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…

  19. Spontaneous bilateral quadriceps tendon rupture.

    PubMed

    Vigneswaran, N; Lee, K; Yegappan, M

    2007-11-01

    Spontaneous bilateral quadriceps tendon ruptures are uncommon. We present a 30-year-old man with end-stage renal failure, who sustained this injury, and subsequently had surgical repair of both tendons on separate occasions. He has since regained full range of movement of both knees.

  20. 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.

  1. Spontaneous remission of membranous glomerulonephritis with successful fetal outcome

    PubMed Central

    Huang, Yan-Mei; Zhou, Hui-Rong; Zhang, Ling; Yang, Ke-Ke; Luo, Jiang-Xi; Zhao, Hai-Lu

    2016-01-01

    Abstract Membranous glomerulonephritis (MGN) represents an immunologically mediated disease characterized by deposition of immune complexes in the glomerular subepithelial space. Persistent proteinuria at diagnosis predicts poor prognosis. Pregnancy with MGN is a risk of fetal loss and may worsen maternal renal function. Here, we report a lady with MGN and proteinuria achieved spontaneous remission and successful fetal outcome naive to any medications. The 26-year old woman had 1-year history of persistent proteinuria (5.5–12.56 g/24 hours) and biopsy-proven MGN. Histopathological characteristics included glomerular basement membrane spikes, subepithelial monoclonal IgG immunofluorescence, and diffuse electron dense deposits. She was sticking to a regular morning exercise routine without any medications. After successful delivery of a full-term baby girl, the mother had improved proteinuria (0.56 g/24 hours) and albuminuria (351.96 g/24 hours contrasting 2281.6 g/24 hours before pregnancy). The baby had normal height and body weight at 4 months old. We identified more pregnancies with MGN in 5 case reports and 5 clinical series review articles (7–33 cases included). Spontaneous remission of maternal MGN with good fetal outcome rarely occurred in mothers on immunosuppressive therapy. Mothers naive to immunosuppressive therapy may achieve spontaneous remission of maternal membranous glomerulonephritis and successful fetal outcome. Theoretically, fetus might donate stem cells to heal mother's kidney. PMID:27368022

  2. Visible-light-assisted electrocatalytic oxidation of methanol using reduced graphene oxide modified Pt nanoflowers-TiO2 nanotube arrays.

    PubMed

    Zhai, Chunyang; Zhu, Mingshan; Bin, Duan; Wang, Huiwen; Du, Yukou; Wang, Chuanyi; Yang, Ping

    2014-10-22

    In this work, Pt nanoflowers deposited on highly ordered TiO2 nanotube arrays (TNTs) by modification of reduced graphene oxide (RGO) nanostructures have been synthesized. The ternary complex (Pt-TNTs/RGO) displays efficient electrocatalytic performance toward methanol oxidation in alkaline medium. The electrochemical impedance spectroscopy (EIS) and responsive photocurrent results indicate that the presence of graphene could effectively promote charge separation during electrocatalytic process. Interestingly, with assistance of visible light illumination, the electrocatalytic activity and stability of the ternary complex electrode toward methanol oxidation are distinctly improved. Both electro- and photo-catalytic processes for methanol oxidation contribute to the enhanced catalytic performance and stability. Moreover, the ternary electrode also displays efficient photoelectrocatalytic degradation of methylene blue (MB) under visible light illumination. The present work sheds light on developing highly efficient and long-term stability catalysts for methanol oxidation with assistance of visible-light illumination. PMID:25275928

  3. Methanol may function as a cross-kingdom signal.

    PubMed

    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

  4. Methanol may function as a cross-kingdom signal.

    PubMed

    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

  5. 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.

  6. Improved Direct Methanol Fuel Cell Stack

    DOEpatents

    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.

  7. Facile synthesis of free-standing Pd-based nanomembranes with enhanced catalytic performance for methanol/ethanol oxidation.

    PubMed

    Wu, Haoxi; Li, Haijuan; Zhai, Yujuan; Xu, Xiaolong; Jin, Yongdong

    2012-03-22

    Macroscopic free-standing Pd and Pd/Pt bimetallic monolayer nanomembranes (Pd- and Pd/Pt-FNMs) derived from the spontaneous self-assembly of the as-produced Pd NPs and Pd/Pt bimetallic NPs at the water-air interface within 15 min are fabricated, respectively. The one-step method allows the growth of high-quality Pd-based FNMs with well-defined monolayer morphology, which exhibit significantly higher electrocatalytic activity for methanol/ethanol oxidation than commercial catalysts.

  8. Laser Cooling without Spontaneous Emission

    NASA Astrophysics Data System (ADS)

    Corder, Christopher; Arnold, Brian; Metcalf, Harold

    2015-01-01

    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.

  9. 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.

  10. Spontaneous internal carotid artery dissection.

    PubMed

    Khimenko, L P; Esham, H R; Ahmed, W

    2000-10-01

    Once considered uncommon, spontaneous dissection of the carotid artery is an increasingly recognized cause of stroke, headache, cranial nerve palsy, or ophthalmologic events, especially in young adults. Even in the presence of existing signs and symptoms, the diagnosis can be missed by experienced physicians of all specialties. We report a case of spontaneous internal carotid artery dissection in a 38-year-old woman with a cortical stroke and visual disturbances as initial symptoms. The diagnosis was confirmed by magnetic resonance imaging/angiography and by angiography. Prompt anticoagulation was instituted, and the patient had complete resolution of symptoms. Cervicocephalic arterial dissection should be included in the differential diagnosis of the causes of cerebrovascular events.

  11. Liquefaction of natural gas to methanol for shipping and storage

    SciTech Connect

    O'Hare, T.E.; Sapienza, R.S.; Mahajan, D.; Skaperdas, G.T.

    1986-07-01

    The penetration of natural gas into distant markets can be substantially increased by a new methanol synthesis process under development at the Brookhaven National Laboratory. The new methanol process is made possible by the discovery of a catalyst that drops synthesis temperatures from about 275/sup 0/C to about 100/sup 0/C. The new low temperature liquid catalyst can convert synthesis gas completely to methanol in a single pass through the methanol synthesis reactor. This characteristic leads to a further major improvement in the methanol plant. As a result of process design factors made possible by the BNL catalyst, the plant required to convert natural gas to methanol is very simple. Conversion of natural gas to methanol requires two chemical reactions, both of which are exothermic, and thus represent a loss of heating value in the feed natural gas. This loss is about 20% of the feed gas energy, and is, therefore, higher than the 10% loss in energy in natural gas liquefaction, which is a simpler physical - not a chemical - change. The energy disadvantage of the methanol option must be balanced against the advantage of a much lower capital investment requirement made possible by the new BNL synthesis. Preliminary estimates show that methanol conversion and shipping require an investment for liquefaction to methanol, and shipping liquefied methanol that can range from 35 to 50% of the capital needed for the LNG plant and LNG tanker fleet. This large reduction in capital requirements is expected to make liquefaction to methanol attractive in many cases where the LNG capital needs are prohibitive. 3 tabs.

  12. 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.

  13. Spontaneous shrinkage of vestibular schwannoma

    PubMed Central

    Romani, Rossana; Pollock, Jonathan

    2016-01-01

    Background: “Watch, wait, and rescan” (WWR) has an established place as a successful management option for a significant proportion of vestibular schwannomas (VS) as an alternative to microsurgical removal or stereotactic radiotherapy. VS may grow slowly and continuously, followed by stagnation or even shrinkage. We present two case reports of spontaneous shrinkage of VS along with a review of the literature. Case Description: A 29-year-old female presented with a progressive history of visual blurring and intermittent diplopia over 2 months. A 29 mm of maximum intracranial diameter (ICD) VS with secondary obstructive hydrocephalus was diagnosed. The patient underwent a ventriculo-peritoneal shunt with resolution of her symptoms and opted for initial WWR management. Interval scanning between 2007 and 2014 showed progressive reduction in the maximum ICD together with reduction in the degree of central tumor enhancement. Maximum ICD at most recent follow up was 22 mm. A 28-year-old female was referred with right sensorineural deafness. A right VS of maximum ICD of 27 mm was diagnosed. Initial WWR management was planned after discussion. Serial imaging showed an initial increase in the size of the tumor followed by progressive reduction in size. The most recent follow up showed a maximum ICD of 20 mm. Conclusion: Early WWR management can be associated with spontaneous shrinkage of VS over time. Prospective clinical study of larger numbers of such cases using the UK VS database may help to identify predictive factors for the spontaneous regression of VS. PMID:27280055

  14. Etiology of primary spontaneous pneumothorax.

    PubMed

    Lyra, Roberto de Menezes

    2016-01-01

    With the advent of HRCT, primary spontaneous pneumothorax has come to be better understood and managed, because its etiology can now be identified in most cases. Primary spontaneous pneumothorax is mainly caused by the rupture of a small subpleural emphysematous vesicle (designated a bleb) or of a subpleural paraseptal emphysematous lesion (designated a bulla). The aim of this pictorial essay was to improve the understanding of primary spontaneous pneumothorax and to propose a description of the major anatomical lesions found during surgery. RESUMO Com o advento da TCAR, o pneumotórax espontâneo primário passou a ser mais bem entendido e conduzido, pois sua etiologia pode ser atualmente identificada na maioria dos casos. O pneumotórax espontâneo primário tem como principal causa a rotura de uma pequena vesícula enfisematosa subpleural, denominada bleb ou de uma lesão enfisematosa parasseptal subpleural, denominada bulla. O objetivo deste ensaio pictórico foi melhorar o entendimento do pneumotórax espontâneo primário e propor uma descrição das principais lesões anatômicas encontradas durante a cirurgia. PMID:27383937

  15. [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.

  16. 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.

  17. 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.

  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. PMID:20734789

  19. 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.

  20. Etherification of extracted crude methanol and conversion of raffinate

    SciTech Connect

    Harandi, M.N.; Owen, H.

    1989-05-02

    A continuous process is described for converting crude methanol to methyl tertiary-alkyl ethers comprising the steps of: (a) contacting a crude methanol feedstock containing a minor amount of water with a liquid hydrocarbon extraction stream rich in C/sub 4/+ iso-alkene hydrocarbons under extraction conditions favorable to selective extraction of the methanol, thereby providing an extract liquid stream rich in methanol and an aqueous raffinate stream lean in methanol; (b) charging the liquid hydrocarbon and extracted methanol substantially free of water to a first catalytic reaction zone for contact with acid etherification catalyst under etherification process conditions for converting methanol to predominantly methyl iso-alkyl ether; (c) fractionating the etherification effluent from step (b) to recover unreacted methanol and light hydrocarbon overhead and C/sub 5/+ methyl tertiary-alkyl ether liquid product; (d) catalytically cracking a heavy hydrocarbon stream and recovering liquid hydrocarbon cracking product, an olefinic liquid hydrocarbon stream containing C/sub 4/+ isoalkene; and a light gas stream; and (e) charging the aqueous raffinate stream from step (a) for conversion of methanol to hydrocarbons concurrently with cracking in step (d).

  1. Extraction of crude methanol and conversion of raffinate

    SciTech Connect

    Harandi, M.N.; Owen, H.

    1989-05-02

    A continuous process is described for converting crude methanol to methyl tertiary-alkyl ethers comprising the steps of: (a) contacting a crude methanolic feedstock containing a minor amount of water with a liquid olefinic hydrocarbon extraction stream rich in C/sub 4/+ iso-alkene hydrocarbon under extraction conditions favorable to selective extraction of the methanol, thereby providing an extract liquid stream rich in methanol and an aqueous raffinate stream lean in methanol; (b) charging liquid hydrocarbon extractant and extracted methanol substantially free of water to a first catalytic reaction zone for contact with acid etherification catalyst under etherification process conditions for converting methanol and iso-alkene hydrocarbon to predominantly methyl tertiary-alkyl ether; (c) fractionating the etherification effluent from step (b) to recover unreacted vapor and to recover unreacted methanol and light olefinic hydrocarbon overhead vapor and to recover liquid product containing methyl tertiary-alkyl ether; (d) catalytically upgrading olefinic overhead vapor from step (c) to provide liquid hydrocarbon product; and (e) charging at least a portion of the aqueous raffinate stream from step (a) for conversion of methanol to hydrocarbons concurrently with olefin upgrading in step (d).

  2. Artificial photosynthesis - CO2 towards methanol

    NASA Astrophysics Data System (ADS)

    Nazimek, D.; Czech, B.

    2011-03-01

    The new insight into the problem of carbon dioxide utilization into valuable compound - methanol and then its transformation into fuel is presented. Because the highly endothermic requirements of the reaction of CO2 hydrogenation a photocatalytic route is applied. Combining of the two reactions: water splitting and CO2 hydrogenation using H2O as a source of hydrogen at the same time and place are proposed. The studies over modified TiO2 catalysts supported on Al2O3 were conducted in a self-designed circulated photocatalytic reaction system under at room temperature and constant pressure. Experimental results indicated that the highest yield of the photoreduction of CO2 with H2O were obtained using TiO2 with the active anatase phase modified by Ru and WO3 addition. The conversion was very high - almost 97% of CO2 was transformed mainly into methanol (14%vol.) and into small amount of formic and acetic acid and ester.

  3. 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.

  4. Probing the evaporation of ternary ethanol-methanol-water droplets by cavity enhanced Raman scattering.

    PubMed

    Howle, Chris R; Homer, Chris J; Hopkins, Rebecca J; Reid, Jonathan P

    2007-10-21

    Cavity enhanced Raman scattering is used to characterise the evolving composition of ternary aerosol droplets containing methanol, ethanol and water during evaporation into a dry nitrogen atmosphere. Measurements made using non-linear stimulated Raman scattering from these ternary alcohol-water droplets allow the in situ determination of the concentration of the two alcohol components with high accuracy. The overlapping spontaneous Raman bands of the two alcohol components, arising from C-H stretching vibrational modes, are spectrally-resolved in stimulated Raman scattering measurements. We also demonstrate that the evaporation measurements are consistent with a quasi-steady state evaporation model, which can be used to interpret the evaporation dynamics occurring at a range of pressures at a particular evaporation time.

  5. Spontaneous mutagenesis: experimental, genetic and other factors.

    PubMed

    Smith, K C

    1992-08-01

    Spontaneous mutations are "the net result of all that can go wrong with DNA during the life cycle of an organism" (Glickman et al., 1986). Thus, the types and amounts of spontaneous mutations produced are the resultant of all the cellular processes that are mutagenic and those that are antimutagenic. It is not widely appreciated that the types and frequencies of spontaneous mutations change markedly with subtle changes in experimental conditions. All types of mutations are produced spontaneously, i.e., base substitutions, frameshifts, insertions and deletions. However, very few papers have appeared that are devoted exclusively to the study of the mechanisms of spontaneous mutagenesis, and of the subtle experimental factors that affect the types and frequencies of spontaneous mutations. This is unfortunate because spontaneous mutagenesis appears to play a major role in evolution, aging, and carcinogenesis. This review emphasizes subtle experimental variables that markedly affect the results of a spontaneous mutation experiment. A thorough understanding of these variables eliminates the need for a theory of "directed" mutagenesis. The intrinsic instability of DNA, and the types of normal metabolic lesions that are produced in DNA that lead to mutations via errors made in replication, repair, and recombination are reviewed, as is the genetic control of spontaneous mutagenesis. As with spontaneous mutagenesis, spontaneous carcinogenesis can also be considered to be the net result of all that can go wrong with DNA during the life of an organism. PMID:1378531

  6. 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.

  7. Support effect in oxide catalysis: methanol oxidation on vanadia/ceria.

    PubMed

    Kropp, Thomas; Paier, Joachim; Sauer, Joachim

    2014-10-15

    Density functional theory is used for periodic models of monomeric vanadia species deposited on the CeO2(111) surface to study dissociative adsorption of methanol and its subsequent dehydrogenation to formaldehyde. Dispersion-corrected PBE+U calculations are performed and compared with HSE and B3LYP results. Dissociative adsorption of methanol at different sites on VO2·CeO2(111) is highly exothermic with adsorption energies of 1.8 to 1.9 eV (HSE+D). Two relevant pathways for desorption of formaldehyde are found with intrinsic barriers for the redox step of 1.0 and 1.4 eV (HSE+D). The calculated desorption temperatures (370 and 495 K) explain the peaks observed in temperature-programmed desorption experiments. Different sites of the supported catalyst system are involved in the two pathways: (i) methanol can chemisorb on the CeO2 surface filling a so-called pseudovacancy and the H atom is transferred to an V-O-Ce interphase bond or (ii) CH3OH may chemisorb at the V-O-Ce interphase bond and form a V-OCH3 species from which H is transferred to the ceria surface, providing evidence for true cooperativity. In both cases, ceria is directly involved in the redox process, as two electrons are accommodated in Ce f states forming two Ce(3+) ions whereas vanadium remains fully oxidized (V(5+)). PMID:25275568

  8. Methanol and ethanol electroxidation using Pt electrodes prepared by the polymeric precursor method

    NASA Astrophysics Data System (ADS)

    Freitas, R. G.; Santos, M. C.; Oliveira, R. T. S.; Bulhões, L. O. S.; Pereira, E. C.

    The results of methanol and ethanol oxidation in acidic medium on Pt electrodes deposited on Ti substrate using the Pechini method are presented. In this route the metallic salts were dissolved in a mixture of ethylene glycol (EG) and citric acid (CA) forming a polyester network, which is painted onto a Ti substrate and then heat treated at 600 °C in order to obtain the metallic Pt thin films. The X-ray diffraction analysis showed the presence of Pt pattern peaks. The presence of the (4 2 0) plane in a higher amount compared to bulk Pt was observed and the peak position of the planes (2 0 0) and (4 2 0) were displaced by approximately -0.3°. The roughness data presented almost the same values for Ti and Ti/Pt. The electrochemical characterization of the electrodes in 0.1 M HClO 4 showed a typical Pt voltammetric profile. Although the voltammetric profiles of Ti/Pt and bulk Pt were the same, the electrocatalytical behavior for methanol oxidation showed an enhancement of the oxidation current density peak, which increased by 170% compared to bulk platinum. Although, the current density peak for ethanol oxidation on Ti/Pt is smaller than for Pt, it began at 0.11 V less positive than the same process on bulk Pt. The chronoamperometric experiments for methanol and ethanol oxidation on Ti/Pt increased by almost 934% and 440%, respectively, compared with Pt bulk.

  9. 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.

  10. 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

  11. Water-methanol separation with carbon nanotubes and electric fields

    NASA Astrophysics Data System (ADS)

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

    2015-07-01

    Methanol is used in various applications, such as fuel for transportation vehicles, fuel cells, and in chemical industrial processes. Conventionally, separation of methanol from aqueous solution is by distillation. However, this method consumes a large amount of energy; hence development of a new method is needed. In this work, molecular dynamics simulations are performed to investigate the effect of an electric field on water-methanol separation by carbon nanotubes (CNTs) with diameters of 0.81 to 4.07 nm. Without an electric field, methanol molecules fill the CNTs in preference to water molecules. The preference of methanol to occupy the CNTs over water results in a separation effect. This separation effect is strong for small CNT diameters and significantly decreases with increasing diameter. In contrast, under an electric field, water molecules strongly prefer to occupy the CNTs over methanol molecules, resulting in a separation effect for water. More interestingly, the separation effect for water does not decrease with increasing CNT diameter. Formation of water structures in CNTs induced by an electric field has an important role in the separation of water from methanol.Methanol is used in various applications, such as fuel for transportation vehicles, fuel cells, and in chemical industrial processes. Conventionally, separation of methanol from aqueous solution is by distillation. However, this method consumes a large amount of energy; hence development of a new method is needed. In this work, molecular dynamics simulations are performed to investigate the effect of an electric field on water-methanol separation by carbon nanotubes (CNTs) with diameters of 0.81 to 4.07 nm. Without an electric field, methanol molecules fill the CNTs in preference to water molecules. The preference of methanol to occupy the CNTs over water results in a separation effect. This separation effect is strong for small CNT diameters and significantly decreases with increasing

  12. 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

  13. 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.

  14. 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).

  15. [Effects of the methanolic extract of Chrysanthemum trifurcatum (Desf.) Batt. and Trab. on rat duodenal motility].

    PubMed

    Ben Sassi, Ahlem; Harzallah-Skhiri, Fethia; Borgi, Wahida; Chouchène, Nabil; Aouni, Mahjoub

    2007-03-01

    The effect of the methanolic extract of flowers of Chrysanthemum trifurcatum (Desf.) Batt. and Trab. Var. macrocephalum (viv.) Beg. on the rat duodenum smooth muscle motility was examined in vitro. The extract has shown dose-dependent stimulator effects on the amplitude of the spontaneous contractions. With 0.1 g/ml of extract, maximal stimulation was obtained. With that dose, the variation (%) was significantly 1050 +/- 13 (P<0.001) compared with control and represented 80 +/- 5.83% (P<0.001) of the maximum effect of acetylcholine. Atropine (2 microg/ml) reduced by 81 +/- 4% (P<0.05) the spasmogenic effects of C. trifurcatum and by 92 +/- 3% (P<0.05) the acetylcholine effects, while papaverine (2 microg/ml) completely inhibited the spasmogenic effects of extract. With a fixed dose of acetylcholine added (20 microg/ml), the extract increases its effect, but acetylcholine decreases its action. These results suggested that the methanolic extract of C. trifurcatum could stimulate duodenal smooth muscle contractions through muscarinic receptors. Thy explain the respective traditional use of plant in gastrointestinal problems, especially constipation.

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Aerobic and anaerobic growth of Paracoccus denitrificans on methanol.

    PubMed

    Bamforth, C W; Quayle, J R

    1978-10-01

    1. The dye-linked methanol dehydrogenase from Paracoccus denitrificans grown aerobically on methanol has been purified and its properties compared with similar enzymes from other bacteria. It was shown to be specific and to have high affinity for primary alcohols and formaldehyde as substrate, ammonia was the best activator and the enzyme could be linked to reduction of phenazine methosulphate. 2. Paracoccus denitrificans could be grown anaerobically on methanol, using nitrate or nitrite as electron acceptor. The methanol dehydrogenase synthesized under these conditions could not be differentiated from the aerobically-synthesized enzyme. 3. Activities of methanol dehydrogenase, formaldehyde dehydrogenase, formate dehydrogenase, nitrate reductase and nitrite reductase were measured under aerobic and anaerobic growth conditions. 4. Difference spectra of reduced and oxidized cytochromes in membrane and supernatant fractions of methanol-grown P. denitrificans were measured. 5. From the results of the spectral and enzymatic analyses it has been suggested that anaerobic growth on methanol/nitrate is made possible by reduction of nitrate to nitrite using electrons derived from the pyridine nucleotide-linked dehydrogenations of formaldehyde and formate, the nitrite so produced then functioning as electron acceptor for methanol dehydrogenase via cytochrome c and nitrite reductase. PMID:718372

  3. 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. ...

  4. 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.

  5. The (perceived) meaning of spontaneous thoughts.

    PubMed

    Morewedge, Carey K; Giblin, Colleen E; Norton, Michael I

    2014-08-01

    Spontaneous thoughts, the output of a broad category of uncontrolled and inaccessible higher order mental processes, arise frequently in everyday life. The seeming randomness by which spontaneous thoughts arise might give people good reason to dismiss them as meaningless. We suggest that it is precisely the lack of control over and access to the processes by which they arise that leads people to perceive spontaneous thoughts as revealing meaningful self-insight. Consequently, spontaneous thoughts potently influence judgment. A series of experiments provides evidence supporting two hypotheses. First, we hypothesize that the more a thought is perceived to be spontaneous, the more it is perceived to provide meaningful self-insight. Participants perceived more spontaneous kinds of thought (e.g., intuition) to reveal greater self-insight than did more controlled kinds of thought in Study 1 (e.g., deliberation). In Studies 2 and 3, participants perceived thoughts with the same content and target to reveal greater self-insight when spontaneously rather than deliberately generated (i.e., childhood memories and impressions formed). Second, we hypothesize that the greater self-insight attributed to thoughts that are (perceived to be) spontaneous leads those thoughts to more potently influence judgment. Participants felt more sexually attracted to an attractive person whom they thought of spontaneously than deliberately in Study 4, and reported their commitment to a current romantic relationship would be more affected by the spontaneous rather than deliberate recollection of a good or bad experience with their romantic partner in Study 5. PMID:24820251

  6. The (perceived) meaning of spontaneous thoughts.

    PubMed

    Morewedge, Carey K; Giblin, Colleen E; Norton, Michael I

    2014-08-01

    Spontaneous thoughts, the output of a broad category of uncontrolled and inaccessible higher order mental processes, arise frequently in everyday life. The seeming randomness by which spontaneous thoughts arise might give people good reason to dismiss them as meaningless. We suggest that it is precisely the lack of control over and access to the processes by which they arise that leads people to perceive spontaneous thoughts as revealing meaningful self-insight. Consequently, spontaneous thoughts potently influence judgment. A series of experiments provides evidence supporting two hypotheses. First, we hypothesize that the more a thought is perceived to be spontaneous, the more it is perceived to provide meaningful self-insight. Participants perceived more spontaneous kinds of thought (e.g., intuition) to reveal greater self-insight than did more controlled kinds of thought in Study 1 (e.g., deliberation). In Studies 2 and 3, participants perceived thoughts with the same content and target to reveal greater self-insight when spontaneously rather than deliberately generated (i.e., childhood memories and impressions formed). Second, we hypothesize that the greater self-insight attributed to thoughts that are (perceived to be) spontaneous leads those thoughts to more potently influence judgment. Participants felt more sexually attracted to an attractive person whom they thought of spontaneously than deliberately in Study 4, and reported their commitment to a current romantic relationship would be more affected by the spontaneous rather than deliberate recollection of a good or bad experience with their romantic partner in Study 5.

  7. Spontaneous colonic adenocarcinoma in marmosets.

    PubMed

    Lushbaugh, C C; Humason, G L; Swartzendruber, D C; Richter, C B; Gengozian, N

    1978-01-01

    We find that colonic adenocarcinoma, which is an extremely rare neoplasm of all animals except man and carcinogen-treated rodents, occurs spontaneously in some marmosets. The cotton-topped Saguinus oedipus oedipus is particularly prone to develop it, but we have found it also at necropsy in Callimico goeldii (Goeldi's marmoset). Numerous metastases to regional lymph nodes develop. The cancers arise de novo in the mucosa and early invade the submucosa and lymphatic apparatus and paracolonic lymph nodes. These findings and the continuing occurrence of this cancer in our colony suggests that the marmoset may be the long-sought primate model for experimental intestinal carcinogenesis.

  8. 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.

  9. Methanol dimer formation drastically enhances hydrogen abstraction from methanol by OH at low temperature.

    PubMed

    Siebrand, Willem; Smedarchina, Zorka; Martínez-Núñez, Emilio; Fernández-Ramos, Antonio

    2016-08-10

    The kinetics of the reaction of methanol with hydroxyl radicals is revisited in light of the reported new kinetic data, measured in cold expansion beams. The rate constants exhibit an approximately 10(2)-fold increase when the temperature decreases from 200 to 50 K, a result that cannot be fully explained by tunneling, as we confirm by new calculations. These calculations also show that methanol dimers are much more reactive to hydroxyl than monomers and imply that a dimer concentration of about 30% of the equilibrium concentration can account quantitatively for the observed rates. The assumed presence of dimers is supported by the observation of cluster formation in these and other cold beams of molecules subject to hydrogen bonding. The calculations imply an important caveat with respect to the use of cold expansion beams for the study of interstellar chemistry. PMID:27479134

  10. 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.

  11. 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.

  12. 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.

  13. Spontaneous mesangiocapillary glomerulonephritis in Finn cross lambs from Alberta.

    PubMed Central

    Frelier, P F; Pritchard, J; Armstrong, D L; Nagge, W T; Lewis, R M

    1984-01-01

    A spontaneous mesangiocapillary glomerulonephritis occurred in three, one to three month old Finnish Landrace cross lambs from a flock in northern Alberta. The ram was a purebred Finn sheep, and the ewes were Finn-Rambouillet and Finn-Suffolk-Rambouillet crosses. The lambs were found dead without previous clinical signs. Histologically there was marked thickening of glomerular capillary basement membranes, proliferation of mesangial cells, and peri-glomerular fibrosis. An interstitial infiltration of plasma cells and lymphocytes was present with occasional tubular degeneration and proteinaceous cast formation. Focal leukoencephalomalacia was present in one lamb. Electron microscopy demonstrated deposition of electron-dense deposits in a subendothelial location with occasional fusion of overlying foot processes in glomerular capillaries. Indirect immunofluorescence studies demonstrated positive staining material in glomerular capillary walls. These findings in Finnish Landrace cross lambs are characteristic of mesangiocapillary glomerulonephritis, a condition heretofore not reported in North America. Images Fig. 1. Fig. 2. PMID:6372972

  14. Protection against methanol-induced retinal toxicity by LED photostimulation

    NASA Astrophysics Data System (ADS)

    Whelan, Harry T.; Wong-Riley, Margaret T. T.; Eells, Janis T.

    2002-06-01

    We have initiated experiments designed to test the hypothesis that 670-nm Light-Emitting Diode (LED) exposure will attenuate formate-induced retinal dysfunction in a rodent model of methanol toxicity. Methanol intoxication produces toxic injury to the retina. The toxic metabolite formed in methanol intoxication is formic acid, a mitochondrial toxin known to inhibit cytochrome oxidase activity. 670-nm LED light has been hypothesized to act by stimulating cytochrome oxidase activity. To test this hypothesis, one group of animals was intoxicated with methanol, a second group was intoxicated with methanol and LED-treated and a third group was untreated. LED treatment (670 nm for 1 min 45 seconds equals 50 mW/cm2, 4 joules/cm2) was administered at 5, 25, and 50 hours after the initial dose of methanol. At 72 hours of methanol intoxication, retinal function was assessed by measurement of ERG responses and retinas were prepared for histologic analysis. ERG responses recorded in methanol-intoxicated animals revealed profound attenuation of both rod-dominated and UV-cone mediated responses. In contrast, methanol- intoxicated animals exposed to LED treatment exhibited a nearly complete recovery of rod-dominated ERG responses and a slight improvement of UV-cone mediated ERG responses. LED treatment also protected the retina against the histopathologic changes produced by formate in methanol intoxication. These data provide evidence that LED phototherapy protects the retina against the cytotoxic actions of formate and are consistent with the hypothesis that LED photostimulation improves mitochondrial respiratory chain function.

  15. Spontaneous biliary peritonitis in children.

    PubMed

    Kohli, Supreethi; Singhal, Anu; Arora, Anita; Singhal, Sanjeev

    2013-01-01

    Pediatric Spontaneous Bile duct perforation is a rare clinical condition with only around 150 cases reported worldwide. Early management gives excellent prognosis but the condition often presents a diagnostic dilemma. Hepato-biliary Technetium-99m-iminodiacetic acid scintiscan is the diagnostic investigation of choice but its availability in third world countries is limited. We present two cases of spontaneous biliary peritonitis in children, which were diagnosed without scintiscanning. The first case was a one-and -a half-year-old child, who was diagnosed with biliary peritonitis without pneumoperitoneum by a combination of Ultrasound (USG), Contrast enhanced computed tomography (CECT), and Magnetic Resonance Imaging (MRI). The child underwent USG-guided drainage and subsequent cholecystectomy with hepatico-jejunostomy. The second child also had biliary peritonitis without pneumoperitoneum, which was initially suspected on USG. CECT revealed dilated gall bladder and fluid collection in sub-hepatic space and pelvis. Abdominal paracentesis revealed presence of bile. The child responded to conservative therapy. Both are doing well on two-year follow-up. In a patient with jaundice, biliary tract abnormalities and/or free fluid, either generalized or localized to peri-cholecystic/sub-hepatic space on USG/CT/MRI, in the absence of pneumoperitoneum, suggest a diagnosis of biliary perforation even in the absence of scintiscanning.

  16. Spontaneous Biliary Peritonitis in Children

    PubMed Central

    Kohli, Supreethi; Singhal, Anu; Arora, Anita; Singhal, Sanjeev

    2013-01-01

    Pediatric Spontaneous Bile duct perforation is a rare clinical condition with only around 150 cases reported worldwide. Early management gives excellent prognosis but the condition often presents a diagnostic dilemma. Hepato-biliary Technetium-99m-iminodiacetic acid scintiscan is the diagnostic investigation of choice but its availability in third world countries is limited. We present two cases of spontaneous biliary peritonitis in children, which were diagnosed without scintiscanning. The first case was a one-and -a half-year-old child, who was diagnosed with biliary peritonitis without pneumoperitoneum by a combination of Ultrasound (USG), Contrast enhanced computed tomography (CECT), and Magnetic Resonance Imaging (MRI). The child underwent USG-guided drainage and subsequent cholecystectomy with hepatico-jejunostomy. The second child also had biliary peritonitis without pneumoperitoneum, which was initially suspected on USG. CECT revealed dilated gall bladder and fluid collection in sub-hepatic space and pelvis. Abdominal paracentesis revealed presence of bile. The child responded to conservative therapy. Both are doing well on two-year follow-up. In a patient with jaundice, biliary tract abnormalities and/or free fluid, either generalized or localized to peri-cholecystic/sub-hepatic space on USG/CT/MRI, in the absence of pneumoperitoneum, suggest a diagnosis of biliary perforation even in the absence of scintiscanning. PMID:24083062

  17. Crows spontaneously exhibit analogical reasoning.

    PubMed

    Smirnova, Anna; Zorina, Zoya; Obozova, Tanya; Wasserman, Edward

    2015-01-19

    Analogical reasoning is vital to advanced cognition and behavioral adaptation. Many theorists deem analogical thinking to be uniquely human and to be foundational to categorization, creative problem solving, and scientific discovery. Comparative psychologists have long been interested in the species generality of analogical reasoning, but they initially found it difficult to obtain empirical support for such thinking in nonhuman animals (for pioneering efforts, see [2, 3]). Researchers have since mustered considerable evidence and argument that relational matching-to-sample (RMTS) effectively captures the essence of analogy, in which the relevant logical arguments are presented visually. In RMTS, choice of test pair BB would be correct if the sample pair were AA, whereas choice of test pair EF would be correct if the sample pair were CD. Critically, no items in the correct test pair physically match items in the sample pair, thus demanding that only relational sameness or differentness is available to support accurate choice responding. Initial evidence suggested that only humans and apes can successfully learn RMTS with pairs of sample and test items; however, monkeys have subsequently done so. Here, we report that crows too exhibit relational matching behavior. Even more importantly, crows spontaneously display relational responding without ever having been trained on RMTS; they had only been trained on identity matching-to-sample (IMTS). Such robust and uninstructed relational matching behavior represents the most convincing evidence yet of analogical reasoning in a nonprimate species, as apes alone have spontaneously exhibited RMTS behavior after only IMTS training.

  18. Crows spontaneously exhibit analogical reasoning.

    PubMed

    Smirnova, Anna; Zorina, Zoya; Obozova, Tanya; Wasserman, Edward

    2015-01-19

    Analogical reasoning is vital to advanced cognition and behavioral adaptation. Many theorists deem analogical thinking to be uniquely human and to be foundational to categorization, creative problem solving, and scientific discovery. Comparative psychologists have long been interested in the species generality of analogical reasoning, but they initially found it difficult to obtain empirical support for such thinking in nonhuman animals (for pioneering efforts, see [2, 3]). Researchers have since mustered considerable evidence and argument that relational matching-to-sample (RMTS) effectively captures the essence of analogy, in which the relevant logical arguments are presented visually. In RMTS, choice of test pair BB would be correct if the sample pair were AA, whereas choice of test pair EF would be correct if the sample pair were CD. Critically, no items in the correct test pair physically match items in the sample pair, thus demanding that only relational sameness or differentness is available to support accurate choice responding. Initial evidence suggested that only humans and apes can successfully learn RMTS with pairs of sample and test items; however, monkeys have subsequently done so. Here, we report that crows too exhibit relational matching behavior. Even more importantly, crows spontaneously display relational responding without ever having been trained on RMTS; they had only been trained on identity matching-to-sample (IMTS). Such robust and uninstructed relational matching behavior represents the most convincing evidence yet of analogical reasoning in a nonprimate species, as apes alone have spontaneously exhibited RMTS behavior after only IMTS training. PMID:25532894

  19. 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.

  20. 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).

  1. A Case of Multiple Spontaneous Keloid Scars

    PubMed Central

    Jfri, Abdulhadi; Rajeh, Nawal; Karkashan, Eman

    2015-01-01

    Keloid scars result from an abnormal healing response to cutaneous injury or inflammation that extends beyond the borders of the original wound. Spontaneous keloid scars forming in the absence of any previous trauma or surgical procedure are rare. Certain syndromes have been associated with this phenomenon, and few reports have discussed the evidence of single spontaneous keloid scar, which raises the question whether they are really spontaneous. Here, we present a 27-year-old mentally retarded single female with orbital hypertelorism, broad nasal bridge, repaired cleft lip and high-arched palate who presented with progressive multiple spontaneous keloid scars in different parts of her body which were confirmed histologically by the presence of typical keloidal collagen. This report supports the fact that keloid scars can appear spontaneously and are possibly linked to a genetic factor. Furthermore, it describes a new presentation of spontaneous keloid scars in the form of multiple large lesions in different sites of the body. PMID:26351423

  2. Methanol oxidation by pEDOT-pSS/PtRu in DMFC

    NASA Astrophysics Data System (ADS)

    Arbizzani, Catia; Biso, Maurizio; Manferrari, Elisa; Mastragostino, Marina

    Direct methanol fuel cells (DMFCs) are attracting more and more attention because of their operating temperature and easy fuel management. While carbons are the most widely used supports for both metal catalysts, i.e. PtRu for methanol oxidation and Pt for oxygen reduction, conducting polymers also can act as suitable supports for catalyst particles because of their conductive and stable three-dimensional structure. We thus chemically synthesized poly(3,4-ethylenedioxythiophene)-polystyrene-4-sulfonate (pEDOT-pSS) with different (3,4-ethylenedioxythiophene):styrene-4-sulfonate (EDOT:SS) molar ratios and prepared the electrocatalytic systems pEDOT-pSS/PtRu and pEDOT-pSS/Pt, the former by both electrochemical and chemical deposition of PtRu and the latter by chemical deposition of Pt. The results of the electrocatalytic activity tests of the pEDOT-pSS/PtRu composite electrodes performed in 0.1 M H 2SO 4-0.5 M CH 3OH liquid solution and in passive, air-breathing DMFC configuration with Nafion ® 115 protonic membrane and 1 M CH 3OH are reported and discussed.

  3. Combined production and purification of hydrogen from methanol using steam iron process in fixed bed reactor

    NASA Astrophysics Data System (ADS)

    Campo, R.; Durán, P.; Plou, J.; Herguido, J.; Peña, J. A.

    2013-11-01

    A research work is being conducted to study the combined production and purification of hydrogen by means of redox processes departing from biomass fast pyrolysis oils (bio-oils). To achieve that goal, methanol has been used as featured material because it is the most representative compound of the alcoholic fraction of bio-oils. The study has been carried out in a fixed bed reactor where methanol decomposes in H2 and CO when gets in contact with a reactive solid based in an iron oxide at temperatures above 600 °C. During the first stage of the “steam-iron” process, reactive gases reduce the iron oxide to metallic iron. Afterward, in a following step, the previously reduced iron is reoxidized by steam producing a high purity hydrogen stream. Although coke deposition does exist during the reducing stage, this behaves as inert during the reoxidation process. Coke inert role has been corroborated by GC, SEM and TEM techniques, showing that carbon deposits were constituted by ordered structures (carbon nanotubes). The determination of the hydrogen production along successive cycles allowed the evaluation of the effect of temperature and alternating reactive atmospheres on the stability of the solid, as well as the optimum conditions for such purpose.

  4. 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.

  5. 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.

  6. 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

  7. 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

  8. Spontaneous Pneumocephalus Associated with Pneumosinus Dilatans

    PubMed Central

    Lee, Jung-Sup; Kwon, Jeong-Taik; Suk, Jong-Sik

    2010-01-01

    The majority of cases of pneumocephalus are secondary to trauma or medical intervention. Spontaneous, non-traumatic pneumocephalus is an uncommon condition. Most cases of spontaneous pneumocephalus require surgery. However, if there is no evidence of infection or cerebrospinal fluid leak, bed rest and follow-up imaging is an alternative treatment. Herein, we report a 31-year-old man with spontaneous pneumocephalus associated with pneumosinus dilatans. PMID:20539803

  9. 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.

  10. 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.

  11. 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.

  12. SPONTANEOUS COAL COMBUSTION; MECHANISMS AND PREDICTION.

    USGS Publications Warehouse

    Herring, James R.; Rich, Fredrick J.

    1983-01-01

    Spontaneous ignition and combustion of coal is a major problem to the coal mining, shipping, and use industries; unintentional combustion causes loss of the resource as well as jeopardy to life and property. The hazard to life is especially acute in the case of underground coal mine fires that start by spontaneous ignition. It is the intention of this research to examine previously suggested causes of spontaneous ignition, to consider new evidence, and to suggest an experimental approach to determine which of these suggested causes is relevant to western U. S. coal. This discussion focuses only on causes and mechanism of spontaneous ignition.

  13. Survey on spontaneous systemic amyloidosis in aging mice.

    PubMed

    Majeed, S K

    1993-02-01

    The incidence of systemic amyloidosis in CD-1 mice (Charles River, caesarian derived) obtained from long term studies over more than a 15-year period is reported. The survey included samples of visceral organs, peripheral and central nervous tissues, bone and bone marrow. The total incidence in all mice of this survey did not show any clear evidence of a difference between males and females. Amyloidosis deposits were mainly seen in the stomach (glandular), heart, small intestines, kidney, liver, spleen, thyroid, parathyroid, adrenals, salivary glands and ovaries, but not in the brain, spinal cord, bone or bone marrow. The survey showed that amyloidosis in CD-1 mice was spontaneous, systemic and it is age-related. Amyloid deposition was extracellular and it stained positively with Congo Red and also stained positively with Oil Red O and Alcian blue. In general, amyloidosis in CD-1 mice, was higher in comparison with B6C3F (cross between C57BL/C6 NCRLB and C3H/HEN NCRLB, (bred by Charles River), CFLP strain (hysterectomy derived strain of Swiss origin) and MAGF: TIF (SPF). This survey also showed that spontaneous systemic amyloidosis in CD-1 mice, was one of the major factors contributory to death in aging CD-1 mice. PMID:8457241

  14. A high-performance platinum electrocatalyst loaded on a graphene hydrogel for high-rate methanol oxidation.

    PubMed

    Wang, Xiluan; Li, Chun; Shi, Gaoquan

    2014-06-01

    Platinum (Pt)-based catalysts used in direct methanol fuel cells (DMFCs) usually suffer from low catalytic activity, slow kinetics of methanol oxidation and poor electrochemical stability. This is mainly due to the toxic effect of carbon monoxide and inefficient use of the Pt catalysts. To address these problems, we immobilized Pt nanoparticles with diameters of 4-6 nm onto the three-dimensional (3D) interpenetrating graphene networks (graphene hydrogel or G-Gel) deposited in the micropores of nickel foam (NF). In this Pt/G-Gel/NF composite catalyst, nearly all the Pt nanoparticles are accessible to methanol and can be efficiently used for electrocatalyzation. It showed excellent electrochemical stability and an activity 2.6 times that of a conventional Pt/reduced graphene oxide (Pt/rGO) composite catalyst. Furthermore, the rate of methanol electro-oxidation at the Pt/G-Gel/NF catalyst can be about 27 times that at the Pt/rGO catalyst, making it applicable for fabricating DMFCs with high current and/or power outputs.

  15. Thermodynamic performances of [mmim]DMP/Methanol absorption refrigeration

    NASA Astrophysics Data System (ADS)

    Chen, Wei; Liang, Shiqiang; Guo, Yongxian; Cheng, Keyong; Gui, Xiaohong; Tang, Dawei

    2012-12-01

    In order to study the theoretical cycle characteristic of [mmim]DMP (1-methyl-3-methylimidazolium dimethylphosphate) /methanol absorption refrigeration, the modified UNIFAC group contribution model and the Wilson model are established through correlating the experimental vapor pressure data of [mmim]DMP/methanol at T=280˜370 K and methanol mole fraction x= 0.529˜0.965. Thermodynamic performances of absorption refrigeration utilizing [mmim]DMP/methanol, LiBr/H2O and H2O/NH3 are investigated and compared with each other under the same operating conditions. From the results, some conclusions are obtained as follows: 1) the circulation ratio of the [mmim]DMP /methanol absorption refrigeration is higher than that of the LiBr/H2O absorption refrigeration, but still can be acceptable and tolerable. 2) The COP of the [mmim]DMP/methanol absorption refrigeration is smaller than that of the LiBr/H2O absorption refrigeration, while it is higher than that of the H2O/NH3 absorption refrigeration under most operating conditions. 3) The [mmim]DMP/methanol absorption refrigeration are still available with high COP when the heat source temperature is too high to drive LiBr/H2O absorption refrigeration.

  16. 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. PMID:26963515

  17. 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.

  18. Exergy analysis of a passive direct methanol fuel cell

    NASA Astrophysics Data System (ADS)

    Bahrami, Hafez; Faghri, Amir

    An analytical, one-dimensional, steady state model is employed to solve for overpotentials at the catalyst layers along with the liquid water and methanol distributions at the anode, and oxygen transport at the cathode. An iterative method is utilized to calculate the cell temperature at each cell current density. A comprehensive exergy analysis considering all possible species inside the cell during normal operation is presented. The contributions of different types of irreversibilities including overpotentials at the anode and cathode, methanol crossover, contact resistance, and proton conductivity of the membrane are investigated. Of all losses, overpotentials in conjunction with the methanol crossover are considered as the major exergy destruction sources inside the cell during the normal operation. While the exergy losses due to electrochemical reactions are more significant at higher current densities, exergy destruction by methanol crossover at the cathode plays more important role at lower currents. It is also found that the first-law efficiency of a passive direct methanol fuel cell increases as the methanol solution in the tank increases in concentration from 1 M to 3 M. However, this is not the case with the second-law efficiency which is always decreasing as the concentration of the methanol solution in the tank increases.

  19. Water–methanol separation with carbon nanotubes and electric fields.

    PubMed

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

    2015-08-01

    Methanol is used in various applications, such as fuel for transportation vehicles, fuel cells, and in chemical industrial processes. Conventionally, separation of methanol from aqueous solution is by distillation. However, this method consumes a large amount of energy; hence development of a new method is needed. In this work, molecular dynamics simulations are performed to investigate the effect of an electric field on water–methanol separation by carbon nanotubes (CNTs) with diameters of 0.81 to 4.07 nm. Without an electric field, methanol molecules fill the CNTs in preference to water molecules. The preference of methanol to occupy the CNTs over water results in a separation effect. This separation effect is strong for small CNT diameters and significantly decreases with increasing diameter. In contrast, under an electric field, water molecules strongly prefer to occupy the CNTs over methanol molecules, resulting in a separation effect for water. More interestingly, the separation effect for water does not decrease with increasing CNT diameter. Formation of water structures in CNTs induced by an electric field has an important role in the separation of water from methanol. PMID:26397004

  20. 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.

  1. 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

  2. Chloroform and dichloromethane biodegradation kinetics with methanol as primary substrate

    SciTech Connect

    Sharma, D.; Suidan, M.T.; Gupta, M.; Sayles, G.D.

    1996-12-31

    Chloroform and dichloromethane biodegradation was studied in a methanogenic environment with methanol as the primary substrate. The rate of chloroform degradation was studied in an anaerobic chemostat containing a mixed microbial culture. A constant concentration of 1.93 g/l of methanol was fed to the chemostat and the chloroform concentration was varied up to 16.74 {mu}M. Biochemical Methane Potential (BMP) tests were conducted in serum bottles to study the kinetics of chloroform and dichloromethane degradation. The maximum rate of chloroform degradation of 0.45 {mu}M/hr was seen at an initial chloroform concentration of 3.85 {mu}M. Chloroform was degraded even without methanol, but the presence of methanol greatly increased the rate of chloroform degradation. However, an increase in methanol concentration beyond 50 mg/l did not increase the rate of degradation of chloroform. Chloroform concentration higher than 6.7{mu}M inhibited the degradation of methanol. The maximum rate of dichloromethane degradation of 0.25 {mu}M/hr was observed corresponding to an initial dichloromethane concentration of 3.34 {mu}M. Methanol was not inhibited even at high concentrations of dichloromethane.

  3. 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

  4. Scaffoldless engineered enzyme assembly for enhanced methanol utilization

    DOE PAGES

    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 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

  5. 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.

  6. Acute effects of aspartame on systolic blood pressure in spontaneously hypertensive rats.

    PubMed

    Kiritsy, P J; Maher, T J

    1986-01-01

    Exogenous tyrosine lowers blood pressure in spontaneously hypertensive rats (SHR). The artificial sweetener aspartame also elevates blood and brain tyrosine levels in rats by being hydrolyzed to phenylalanine, which is then rapidly hydroxylated to tyrosine in the liver. Hence we tested the ability of aspartame; its hydrolytic products phenylalanine, aspartic acid and methanol; and of tyrosine itself to lower blood pressure in SHR. For one week prior to experimentation rats were acclimated to the indirect blood pressure measurement technique; on the day of an experiment they received I.P. injections (mg/kg) of aspartame (12.5-200), tyrosine (25-200) or phenylalanine (100-200), or of aspartic acid or methanol in the doses theoretically contained within 200 mg/kg aspartame. Animals receiving 50, 100 or 200 mg/kg of aspartame exhibited maximum falls in blood pressure of 17.3, 24.2 and 19.3 mmHg, respectively. All changes were significant, as determined by ANOVA and the Newman-Keuls test (p less than 0.05). Tyrosine or phenylalanine also lowered blood pressure, but aspartic acid or methanol produced no significant effects. Co-administration of aspartame with valine, a large neutral amino acid that competes with phenylalanine or tyrosine for brain uptake, attenuated aspartame's hypotensive effect. These observations suggest that the neurochemical changes produced by aspartame lead to predicted tyrosine-induced changes in blood pressure.

  7. Whole Spontaneous Spinal Epidural Hematoma

    PubMed Central

    Yoon, Kyeong-Wook; Song, Jae Gyok; Ryu, Jae-Wook

    2014-01-01

    A 26-year-old male who had no underlying disease, including coagulopathy, underwent thoracotomy and bleeding control due to hemothorax. On the fifth postoperative day, paralysis of both lower limbs occurred. Urgent spine magnetic resonance imaging showed a massive anterior spinal epidural hematoma from C2 to L1 level with different signal intensities, which was suspected to be staged hemorrhage. Hematoma evacuation with decompressive laminectomy was performed. The patient's neurologic deterioration was recovered immediately, and he was discharged without neurological deficits. A drug history of naftazone, which could induce a drug-induced platelet dysfunction, was revealed retrospectively. To our knowledge, this is the first report of whole spontaneous spinal epidural hematoma in a young patient, with a history of hemorrhoid medication. PMID:24967052

  8. Fog spontaneously folds mosquito wings

    NASA Astrophysics Data System (ADS)

    Dickerson, Andrew K.; Liu, Xing; Zhu, Ting; Hu, David L.

    2015-02-01

    The flexibility of insect wings confers aerodynamic benefits, but can also present a hazard if exposed to fog or dew. Fog can cause water to accumulate on wings, bending them into tight taco shapes and rendering them useless for flight. In this combined experimental and theoretical study, we use high-speed video to film the spontaneous folding of isolated mosquito wings due to the evaporation of a water drop. We predict shapes of the deformed wing using two-dimensional elastica theory, considering both surface tension and Laplace pressure. We also recommend fold-resistant geometries for the wings of flapping micro-aerial vehicles. Our work reveals the mechanism of insect wing folding and provides a framework for further study of capillarity-driven folding in both natural and biomimetic systems at small scales.

  9. Spontaneous UC emission from SSTRa

    SciTech Connect

    Kutschera, W.; Ahmad, I.; Armato S.G. III; Friedman, A.M.; Gindler, J.E.; Henning, W.; Ishii, T.; Paul, M.; Rehm, K.E.

    1985-12-01

    The spontaneous emission of UC from SSTRa, recently discovered by Rose and Jones, has been confirmed, and the mass of the emitted particles unambiguously identified. The present measurement was performed with a SSXTh source containing 9.2 mCi of SSTRa. An Enge split-pole magnetic spectrograph was used to suppress the intense alpha radiation and to identify the UC particles. The spectrograph was calibrated with tandem-accelerated beams of UC, TC, and SC. In six days of decay counting, twenty-four UC events were observed yielding a branching ratio of (4.7 +- 1.3) x 10 for the emission of UC from SSTRa relative to that of alpha particles. The value is in fair agreement with the result of Rose and Jones, (8.5 +- 2.5) x 10 , and with more recent measurements from other laboratories.

  10. Detailed description of spontaneous emission

    NASA Astrophysics Data System (ADS)

    Guryev, M. V.

    2012-08-01

    The wave side of wave-photon duality, describing light as an electromagnetic field (EMF), is used in this article. The EMF of spontaneous light emission (SE) of a laser-excited atom is calculated from first principles for the first time. This calculation is done using the simple method of atomic quantum electrodynamics. The EMF of SE is also calculated for three types of polyatomic light sources excited by a laser. It is shown that light radiated by such sources can be coherent, which explains recent experiments on SE of laser-excited atoms. Small sources of SE can be superradiant, which also conforms to experiment. Thus, SE is shown not to be a random event itself. Random properties of natural light are simply explained as a result of thermal excitation randomness without additional hypotheses. The EMF of SE is described by simple complex functions, but not real ones.

  11. Spontaneous Pneumoperitoneum due to Constipation

    PubMed Central

    Yamana, Ippei; Noritomi, Tomoaki; Takeno, Shinsuke; Tatsuya, Hashimoto; Sato, Keisuke; Shimaoka, Hideki; Yamaguchi, Ryosuke; Ishii, Fumiaki; Yamada, Teppei; Yamashita, Yuichi

    2015-01-01

    We report a rare case of spontaneous pneumoperitoneum. An 82-year-old Japanese male patient was referred to our hospital because of constipation and abdominal pain. Abdominal computed tomography revealed a large amount of feces in the colon and rectum, and free air in the abdomen. Based on these findings, the patient was diagnosed with gastrointestinal perforation. Emergency exploratory laparotomy was performed. Neither perforation nor ischemic changes were recognized in the digestive tract. The patient's defecation was managed postoperatively until discharge on the 13th postoperative day. The authors assumed that free air, which was released after a mucosal injury due to the internal pressure caused by the presence of a large amount of feces in the colon and rectum, had penetrated the bowel wall through the bowel mucosa. We herein report the present case while also reviewing the pertinent literature. PMID:26676063

  12. Spontaneous Spinal Epidural Hematoma Report.

    PubMed

    Kukreja, Sunil; Nanda, Anil

    2016-01-01

    We report a case of spontaneous spinal epidural hematoma in a 12-year-old female, who presented with significant upper and lower extremities weakness preceded by pain around the neck and shoulder girdle. Magnetic resonance imaging revealed epidural hematoma extending from C6-T2 with characteristic heterogeneously hyperintensity on T2 and homogenously isointensity on T1. Emergent spinal decompression was performed. However, the patient remained substantially weak in her lower extremities and was wheelchair bound at 3 months postoperatively. We have discussed clinical features, predisposing events, pathogenesis and treatment guidelines described in the literature. We also aim to reinforce the notion of keeping a high degree of clinical suspicion to identify and intervene at the earliest stage to prevent the physically and socially challenging consequences of SSEH. PMID:27598898

  13. Spontaneous rupture on irregular faults

    NASA Astrophysics Data System (ADS)

    Liu, C.

    2014-12-01

    It is now know (e.g. Robinson et al., 2006) that when ruptures propagate around bends, the rupture velocity decrease. In the extreme case, a large bend in the fault can stop the rupture. We develop a 2-D finite difference method to simulate spontaneous dynamic rupture on irregular faults. This method is based on a second order leap-frog finite difference scheme on a uniform mesh of triangles. A relaxation method is used to generate an irregular fault geometry-conforming mesh from the uniform mesh. Through this numerical coordinate mapping, the elastic wave equations are transformed and solved in a curvilinear coordinate system. Extensive numerical experiments using the linear slip-weakening law will be shown to demonstrate the effect of fault geometry on rupture properties. A long term goal is to simulate the strong ground motion near the vicinity of bends, jogs, etc.

  14. Spontaneous adrenal haemorrhage in pregnancy

    PubMed Central

    A, Anagnostopoulos; S, Sharma

    2011-01-01

    The authors present a case of spontaneous adrenal haemorrhage, in a 28-year-old woman at 36 weeks of a twin pregnancy. Initial symptom was sudden onset chest pain which soon migrated to abdomen, accompanied by hypovolaemic shock and fetal bradycardia. Subsequent caesarean section for suspected placental abruption and resuscitation with nine units of blood, 10 of cryoprecipitate, four of fresh frozen plasma and two of platelets, in order to treat anaemia of Hgb of 3.6 g/dl and disseminated intravascular coagulation, failed to stabilise the woman. A CT scan of abdomen and pelvis then revealed a 15×17×17 cm retroperitoneal haematoma, secondary to right adrenal haemorrhage. Management was with laparotomy drainage and packing of the retroperitoneal haematoma along with the use of activated factor VII. Adrenal haemorrhage in pregnancy is an extremely rare, acute, life-threatening condition, presenting with non-specific symptoms. PMID:22679231

  15. Erythrocytosis in Spontaneously Hypertensive Rats

    PubMed Central

    Sen, Subha; Hoffman, George C.; Stowe, Nicholas T.; Smeby, Robert R.; Bumpus, F. Merlin

    1972-01-01

    During the study of an inbred strain of Wistar rats which spontaneously develop hypertension when they reach a weight of approximately 150 g, it was found that these animals also develop an erythrocytosis. A significant increase in red cell count was observed in spontaneously hypertensive (SH) rats (8-11 × 106 RBC/mm3) when compared with normotensive rats (6-7 × 106 RBC/mm3) of the same strain. This increase in red cell count paralleled the increase in body weight and the rise in blood pressure. Since the plasma volume, as measured with labeled albumin was normal, there was an absolute increase in red cells. The hematocrit and hemoglobin content of the blood measured in SH rats were only slightly greater than those found in normotensive rats. However, the mean cell volume (MCV) of the red cells in the SH rats was 45-47 μ3 as compared with 51-53 μ3 in normotensive rats. A fourfold increase in 24 hr 59Fe incorporation into the red cells was found in the SH rats when compared with normotensive controls. The bone marrow of the SH rats showed erythroid hyperplasia. When the SH rats were treated with α-methyldopa (Aldomet 200 mg/kg daily, i.p.) the red cell count fell in parallel with the drop in blood pressure. No change in red cell count or blood pressure was observed in normotensive rats treated in the same manner. The erythropoietin titer was high in SH rats, and was undetectable in normotensive rats. These observations suggest a direct relationship between the hypertension and the erythrocytosis mediated by erythropoietin; both are genetically controlled. PMID:5011107

  16. 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.

  17. Kinetic relationships governing addition of methanol to methyl acrylate

    SciTech Connect

    Chubarov, G.A.; Danov, S.M.; Kutnyaya, M.Yu.

    1988-11-10

    The kinetic relationships governing the addition of methanol to methyl acrylate and the reverse reaction, i.e., the elimination of methanol from methyl /beta/-methoxypropionate catalyzed by sulfuric and p-toluenesulfonic acids, were investigated. The rate of the forward reaction depends on the concentrations of methyl acrylate, methanol, and the catalyst, and the rate of the reverse reaction depends on the concentration of methyl /beta/-methoxypropionate and of the catalyst. A kinetic expression which describes the process well was obtained.

  18. 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

  19. 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.

  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. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. Electro-oxidation of carbon monoxide and methanol on bare and Pt-modified Ru(1010) electrodes.

    PubMed

    Pinheiro, A L N; Zei, M S; Ertl, G

    2005-03-21

    The activity towards CO and methanol electrooxidation of bare and platinum-modified Ru(1010) surfaces has been investigated. The structure/morphology and composition of the modified surfaces were characterized using electron diffraction techniques (LEED, RHEED) and Auger spectroscopy. The bare Ru(1010) surface exhibits a higher catalytic activity towards CO electrooxidation than the Ru(0001) surface due to the lower oxidation potential of the former surface. The early stages of surface oxidation lead to disordering of the surface and further enhancing of the electrocatalytic activity. Electrodeposition of Pt on Ru(1010) leads to epitaxial growth via a Volmer-Weber growth mode. The Pt clusters grow preferentially with the (311) plane parallel to the substrate surface with (011) rows in the layers in contact with the substrate compressed by about 3% with respect to bulk Pt, in order to match with the (1210) rows of the Ru(1010) surface. This compression leads to enhanced catalytic activity towards CO oxidation for thin Pt deposits whereas for large deposited Pt particles the dominating factor for the catalytic enhancement is the higher concentration of surface defects. On the other hand, in the case of methanol oxidation, the dominant factor in determining the catalytic activity is the concentration of adjacent Pt-Ru sites, although surface defects play an important role in the methanol dehydrogenation steps.

  7. 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.

  8. Surface structure and reaction property of CuCl2-PdCl2 bimetallic catalyst in methanol oxycarbonylation: A DFT approach

    NASA Astrophysics Data System (ADS)

    Meng, Qingsen; Wang, Shengping; Shen, Yongli; Yan, Bing; Wu, Yuanxin; Ma, Xinbin

    2014-02-01

    Surface structure of CuCl2-PdCl2 bimetallic catalyst (Wacker-type catalyst) was built employing density functional theory (DFT) calculations, and the reaction mechanism of methanol oxycarbonylation over the CuCl2-PdCl2 surfaces was also investigated. On the CuCl2-PdCl2 surface, the active site for methanol oxidation was confirmed as Cu-Cl-Cu (Pd). Comparing with pure CuCl2 surface, the introduction of Pd atom causes the electron repopulation on the surface and lowers the energy barrier for methanol oxidation, but the number of the active site decreases with the increasing of Pd doping volume. Agreed with previous experimental results, the Pd site is most favorable for the CO insertion, indicated by the lowest activation barrier for the formation of COOCH3 on Pd atom. The lowest energy barrier for the formation of DMC appears when COOCH3 species adsorbed on Pd atom and methoxyl adsorbed on Cu atoms, which is 0.42 eV. Finally, the reconstruction of the unsaturated surface is a spontaneous and exothermic process. Comparing with other surfaces, the rate-limiting step, methanol oxidation, on CuCl2-PdCl2 surface with Pd/Cu = 1:17 has the lowest energy barrier, which is agreed with the experimental observation that PdCl2-CuCl2 catalyst with Pd/Cu = 1:20 has the favorable activity. The adsorbed methoxyl will further lower the activation barrier of methanol oxidation, which is agreed with experimental observation that the Wacker-type catalysts have an induction period in the methanol oxidative carbonylation system.

  9. Spontaneous fission properties and lifetime systematics

    SciTech Connect

    Hoffman, D.C.

    1989-03-01

    Half-lives for spontaneous fission of nuclides with even and odd numbers of particles are compared with recent theoretical calculations. A summary of odd particle hindrance factors is given. The most recent measurements of kinetic-energy and mass distributions and neutron emission for spontaneous fission of the heaviest nuclides are summarized and discussed. 51 refs., 9 figs.

  10. Spontaneous pneumomediastinum: A complication of swine flu.

    PubMed

    Padhy, Ajit Kumar; Gupta, Anubhav; Aiyer, Palash; Jhajhria, Narender Singh; Grover, Vijay; Gupta, Vijay Kumar

    2015-10-01

    The occurrence of spontaneous pneumomediastinum in swine flu, or H1N1 influenza A infection, is a rare phenomenon and only few cases have been reported in children. We describe a case of spontaneous pneumomediastinum in adult infected with swine flu.

  11. Abstracting in the Context of Spontaneous Learning

    ERIC Educational Resources Information Center

    Williams, Gaye

    2007-01-01

    There is evidence that spontaneous learning leads to relational understanding and high positive affect. To study spontaneous abstracting, a model was constructed by combining the RBC model of abstraction with Krutetskii's mental activities. Using video-stimulated interviews, the model was then used to analyze the behavior of two Year 8 students…

  12. Simultaneous and spontaneous bilateral quadriceps tendons rupture.

    PubMed

    Celik, Evrim Coşkun; Ozbaydar, Mehmet; Ofluoglu, Demet; Demircay, Emre

    2012-07-01

    Simultaneous and spontaneous bilateral quadriceps tendon rupture is an uncommon injury that is usually seen in association with multiple medical conditions and some medications. We report a case of simultaneous and spontaneous bilateral quadriceps tendon rupture that may be related to the long-term use of a statin.

  13. Spontaneity and Equilibrium II: Multireaction Systems

    ERIC Educational Resources Information Center

    Raff, Lionel M.

    2014-01-01

    The thermodynamic criteria for spontaneity and equilibrium in multireaction systems are developed and discussed. When N reactions are occurring simultaneously, it is shown that G and A will depend upon N independent reaction coordinates, ?a (a = 1,2, ..., N), in addition to T and p for G or T and V for A. The general criteria for spontaneity and…

  14. Children's Spontaneous Vocalisations during Play: Aesthetic Dimensions

    ERIC Educational Resources Information Center

    Countryman, June; Gabriel, Martha; Thompson, Katherine

    2016-01-01

    This paper explores the phenomenon of spontaneous vocalisations in the self-chosen, unstructured outdoor play of children aged 3-12. Spontaneous vocalisations encompass the whole range of children's unprompted, natural, expressive vocal soundings beyond spoken language. Non-participant observations at childcare centres and on elementary school…

  15. Spontaneous thrombosis of a pseudoaneurysm complicating pancreatitis.

    PubMed

    Vanlangenhove, P; Defreyne, L; Kunnen, M

    1999-01-01

    Patients with a visceral aneurysm are at high risk for acute transpapillary, intra-, or retroperitoneal hemorrhage, necessitating either surgical or endovascular therapy. We report an instance of spontaneous thrombosis of a pseudoaneurysm complicating pancreatitis before endovascular treatment could be performed. Causality and the literature of spontaneous thrombosis in pseudoaneurysms are discussed.

  16. 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.

  17. Fatal congenital myopathy with actin filament deposits.

    PubMed

    Bornemann, A; Petersen, M B; Schmalbruch, H

    1996-07-01

    We present the clinical and morphological findings in a case of progressive congenital myopathy. The symptoms present at birth included severe general muscular hypotonia, diffuse muscular atrophy, arthrogryposis, absence of spontaneous movements, and left ventricular hypertrophy. A biopsy specimen taken from the gastrocnemius muscle when the patient was 2 weeks old revealed deposits which consisted of actin filaments as shown by electron microscopy. The infant was occasionally respirator dependent but was mostly able to breathe unassisted. At the age of 5 months he died of respiratory failure. The actin filament deposits may explain the clinical findings.

  18. 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.

  19. 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

  20. Architecturally designed Pt-MoS2 and Pt-graphene composites for electrocatalytic methanol oxidation.

    PubMed

    Patil, Sagar H; Anothumakkool, Bihag; Sathaye, Shivaram D; Patil, Kashinath R

    2015-10-21

    Thin films consisting of platinum nanoparticles (Pt NPs) with uniform size and distribution have been successfully prepared at a liquid-liquid interface. Apart from the usual substrates like glass, Si etc. the films were also deposited on the surfaces of MoS2 thin films and graphene nanosheets (GNS) respectively, by using a layer-by-layer (LbL) deposition technique to form Pt-MoS2 and Pt-GNS composites. The loading concentration of Pt NPs on MoS2 and GNS can be adjusted by selecting the number and sequence of the component layers during LbL deposition. The Pt thin films, Pt-MoS2 and Pt-GNS nanocomposite thin films are characterized using transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), energy dispersive X-ray spectrometry (EDS), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). TEM results of the composites show that Pt NPs with sizes in the range of 1 to 3 nm are uniformly dispersed on the MoS2/GNS surface. The catalytic activities of Pt and Pt-composites for the reaction of methanol oxidation are studied using cyclic voltammetry and chronoamperometry. Electrochemical studies reveal that both the Pt-MoS2 and Pt-GNS nanocomposites show excellent electrocatalytic activity towards methanol oxidation. Pt-MoS2 and Pt-GNS nanocomposite electrodes show excellent stability for reuse of the catalyst. A probable mechanism of catalysis has been discussed. We propose that the similar architecture reported here would be promising for the synthesis of high performance catalysts for fuel cells, gas phase reactions, and other applications such as sensors. PMID:26377752

  1. Measurement of spontaneity: the relationship between intensity and frequency of the spontaneous experience.

    PubMed

    Kipper, David A; Buras, Eva

    2009-04-01

    In the present article, the construct validity of one aspect of the definition of spontaneity is examined. Two ways of measuring spontaneity are presented. One involves the use of the revised version of a Spontaneity Assessment Inventory in which respondents are asked to indicate the intensity of the feeling of spontaneity they experience during a typical day. The second was a specially worded version of the Spontaneity Assessment Inventory-Revised: respondents were asked to indicate the frequency with which they experienced spontaneity during a typical day. 81 students responded to the two versions, which were given 1 wk. apart. The order of administration of the two versions was counterbalanced across the participants. The very high positive correlation between versions (r = .84) suggests that either measure may be used as an estimator of spontaneity.

  2. 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.

  3. Production of chemicals from methanol. I. Low molecular weight olefins

    SciTech Connect

    Kaeding, W.W.; Butter, S.A.

    1980-01-01

    Methanol has been converted to water and hydrocarbons, with up to 70% selectivity to C/sub 2/-C/sub 4/ olefins, at 100% conversion, over ZSM-5 class zeolite catalysts modified with phosphorus compounds. Ethylene is proposed as the initial hydrocarbon produced. Evidence for the alkylation of olefins with methanol or methyl ether over these catalysts to produce higher molecular weight olefins is presented. 2 figures, 5 tables.

  4. Nitratotris(triphenyl­phosphine)copper(I) methanol solvate

    PubMed Central

    Steyl, Gideon

    2009-01-01

    The title compound, [Cu(NO3)(C18H15P)3]·CH3OH, is a methanol solvate derivative of nitratotris(triphenyl­phos­phine)copper(I). The complex crystallizes with three triphenyl­phosphine ligands coordinated to the copper centre, with an O—H⋯O hydrogen bond observed between the nitrate ligand and the methanol solvent mol­ecule. The coordination around the CuI centre is distorted tetrahedral. PMID:21582060

  5. Synthesis of 3D structured graphene as a high performance catalyst support for methanol electro-oxidation

    NASA Astrophysics Data System (ADS)

    Li, Yecheng; Zhang, Lei; Hu, Zhuofeng; Yu, Jimmy C.

    2015-06-01

    A simple process for preparing 3D structured graphene (3D-G) by a solution combustion method is reported. The product was deposited with platinum and used for methanol electro-oxidation. The catalyst shows a considerable enhancement in both the activity and stability towards methanol electro-oxidation reaction. Characterization reveals that the Pt/3D-G catalyst has a more negative onset potential as well as a higher electrochemically active specific surface area than a commercial Pt/C catalyst. Moreover, the catalyst exhibits higher tolerance to corrosion than carbon black. This work provides an efficient way for preparing 3D-G as a promising support for the oxidation of small organic molecules in fuel cells.

  6. Coke Formation in a Zeolite Crystal During the Methanol-to-Hydrocarbons Reaction as Studied with Atom Probe Tomography.

    PubMed

    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

    2016-09-01

    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 (13) C-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 (13) C 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. This nanoscale correlation underscores the importance of carefully engineering materials to suppress detrimental coke formation.

  7. 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; 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 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

  8. Coke Formation in a Zeolite Crystal During the Methanol-to-Hydrocarbons Reaction as Studied with Atom Probe Tomography.

    PubMed

    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

    2016-09-01

    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 (13) C-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 (13) C 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. This nanoscale correlation underscores the importance of carefully engineering materials to suppress detrimental coke formation. PMID:27485276

  9. 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.

  10. Effects of the Methanolic Extract of Vitellaria paradoxa Stem Bark Against Scopolamine-Induced Cognitive Dysfunction and Oxidative Stress in the Rat Hippocampus.

    PubMed

    Foyet, Harquin Simplice; Asongalem, Acha Emmanuel; Oben, Eyong Kenneth; Cioanca, Oana; Hancianu, Monica; Hritcu, Lucian

    2016-10-01

    Vitellaria paradoxa C.F. Gaertn (Sapotaceae) is a perennial three which naturally grows in the northern part of Cameroon. It has been traditionally used in the Cameroonian folk medicine for treating inflammation and pain. In the present study, we evaluate the possible anti-amnesic and antioxidative effects of the methanolic extract of V. paradoxa stem bark in an Alzheimer's disease (AD) rat model of scopolamine. Rats received a single injection of scopolamine (1.5 mg/kg) before behavioral testing and were treated with the methanolic extract (25 and 50 mg/kg), daily, for eight continuous days. Also, the antioxidant activity in the hippocampus was assessed using the total content of reduced glutathione and malondialdehyde levels. The scopolamine-treated rats exhibited the following: decrease of exploratory time and discrimination index within the novel object recognition test, decrease of spontaneous alternations percentage within Y-maze task, and increase of working memory errors, reference memory errors, and time taken to consume all five baits within radial arm-maze task. Administration of the methanolic extract significantly improved these parameters, suggesting positive effects on memory formation processes and antioxidant potential. Our results suggest that the methanolic extract ameliorates scopolamine-induced memory impairment by attenuation of the oxidative stress in the rat hippocampus.

  11. Effects of the Methanolic Extract of Vitellaria paradoxa Stem Bark Against Scopolamine-Induced Cognitive Dysfunction and Oxidative Stress in the Rat Hippocampus.

    PubMed

    Foyet, Harquin Simplice; Asongalem, Acha Emmanuel; Oben, Eyong Kenneth; Cioanca, Oana; Hancianu, Monica; Hritcu, Lucian

    2016-10-01

    Vitellaria paradoxa C.F. Gaertn (Sapotaceae) is a perennial three which naturally grows in the northern part of Cameroon. It has been traditionally used in the Cameroonian folk medicine for treating inflammation and pain. In the present study, we evaluate the possible anti-amnesic and antioxidative effects of the methanolic extract of V. paradoxa stem bark in an Alzheimer's disease (AD) rat model of scopolamine. Rats received a single injection of scopolamine (1.5 mg/kg) before behavioral testing and were treated with the methanolic extract (25 and 50 mg/kg), daily, for eight continuous days. Also, the antioxidant activity in the hippocampus was assessed using the total content of reduced glutathione and malondialdehyde levels. The scopolamine-treated rats exhibited the following: decrease of exploratory time and discrimination index within the novel object recognition test, decrease of spontaneous alternations percentage within Y-maze task, and increase of working memory errors, reference memory errors, and time taken to consume all five baits within radial arm-maze task. Administration of the methanolic extract significantly improved these parameters, suggesting positive effects on memory formation processes and antioxidant potential. Our results suggest that the methanolic extract ameliorates scopolamine-induced memory impairment by attenuation of the oxidative stress in the rat hippocampus. PMID:26620052

  12. Subduction initiation: spontaneous and induced

    NASA Astrophysics Data System (ADS)

    Stern, Robert J.

    2004-10-01

    The sinking of lithosphere at subduction zones couples Earth's exterior with its interior, spawns continental crust and powers a tectonic regime that is unique to our planet. In spite of its importance, it is unclear how subduction is initiated. Two general mechanisms are recognized: induced and spontaneous nucleation of subduction zones. Induced nucleation (INSZ) responds to continuing plate convergence following jamming of a subduction zone by buoyant crust. This results in regional compression, uplift and underthrusting that may yield a new subduction zone. Two subclasses of INSZ, transference and polarity reversal, are distinguished. Transference INSZ moves the new subduction zone outboard of the failed one. The Mussau Trench and the continuing development of a plate boundary SW of India in response to Indo-Asian collision are the best Cenozoic examples of transference INSZ processes. Polarity reversal INSZ also follows collision, but continued convergence in this case results in a new subduction zone forming behind the magmatic arc; the response of the Solomon convergent margin following collision with the Ontong Java Plateau is the best example of this mode. Spontaneous nucleation (SNSZ) results from gravitational instability of oceanic lithosphere and is required to begin the modern regime of plate tectonics. Lithospheric collapse initiates SNSZ, either at a passive margin or at a transform/fracture zone, in a fashion similar to lithospheric delamination. The theory of hypothesis predicts that seafloor spreading will occur in the location that becomes the forearc, as asthenosphere wells up to replace sunken lithosphere, and that seafloor spreading predates plate convergence. This is the origin of most boninites and ophiolites. Passive margin collapse is a corollary of the Wilson cycle but no Cenozoic examples are known; furthermore, the expected strength of the lithosphere makes this mode unlikely. Transform collapse SNSZ appears to have engendered new

  13. Subduction initiation: spontaneous and induced

    NASA Astrophysics Data System (ADS)

    2004-10-01

    The sinking of lithosphere at subduction zones couples Earth's exterior with its interior, spawns continental crust and powers a tectonic regime that is unique to our planet. In spite of its importance, it is unclear how subduction is initiated. Two general mechanisms are recognized: induced and spontaneous nucleation of subduction zones. Induced nucleation (INSZ) responds to continuing plate convergence following jamming of a subduction zone by buoyant crust. This results in regional compression, uplift and underthrusting that may yield a new subduction zone. Two subclasses of INSZ, transference and polarity reversal, are distinguished. Transference INSZ moves the new subduction zone outboard of the failed one. The Mussau Trench and the continuing development of a plate boundary SW of India in response to Indo Asian collision are the best Cenozoic examples of transference INSZ processes. Polarity reversal INSZ also follows collision, but continued convergence in this case results in a new subduction zone forming behind the magmatic arc; the response of the Solomon convergent margin following collision with the Ontong Java Plateau is the best example of this mode. Spontaneous nucleation (SNSZ) results from gravitational instability of oceanic lithosphere and is required to begin the modern regime of plate tectonics. Lithospheric collapse initiates SNSZ, either at a passive margin or at a transform/fracture zone, in a fashion similar to lithospheric delamination. The theory of hypothesis predicts that seafloor spreading will occur in the location that becomes the forearc, as asthenosphere wells up to replace sunken lithosphere, and that seafloor spreading predates plate convergence. This is the origin of most boninites and ophiolites. Passive margin collapse is a corollary of the Wilson cycle but no Cenozoic examples are known; furthermore, the expected strength of the lithosphere makes this mode unlikely. Transform collapse SNSZ appears to have engendered new

  14. 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

  15. 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

  16. Themophilic biofiltration of methanol and alpha-pinene.

    PubMed

    Dhamwichukorn, S; Kleinheinz, G T; Bagley, S T

    2001-03-01

    Biofiltration systems utilizing thermophilic (55 degrees C) bacteria were constructed and tested for the removal of methanol and alpha-pinene--two important volatile organic compounds (VOCs) in the forest products industry. Thermophilic bacterial mixtures that can degrade both methanol and alpha-pinene were obtained via enrichment techniques. Two bench-scale thermophilic biofiltration systems (1085 and 1824 cm3) were used to examine compound removals at different residence times, with influent concentrations of 110 ppmv methanol and 15 ppmv alpha-pinene. At a residence time of 10.85 min, the smaller system had removal efficiencies of >98% for methanol, but only 23% for alpha-pinene. The larger system was operated with the same parameters to evaluate residence time and surfactant effects on compound removals. At a residence time of 18.24 min, both methanol and alpha-pinene removal rates were > or = 95%. However, a-pinene removal dropped to 26% at a residence time of 6.08 min; methanol removal was not affected. Subsequent addition of a surfactant mixture increased a-pinene removal to 94% at the shortest residence time. No residual alpha-pinene was detected with the support medium Celite R-635, indicating that the surfactant may increase mass transfer of alpha-pinene.

  17. 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.

  18. The Federal Methanol Fleet: Summary of technical data

    SciTech Connect

    McGill, R.N.; Graves, R.L.; West, B.H. ); Hodgson, J.W. )

    1991-04-01

    The Federal Methanol Fleet, initiated in 1985 with an appropriation from the US Congress, is now in its final stages of operation. A great deal has been learned while vehicles have accumulated approximately 1.4 million miles (2.2 million kilometers) in routine government fleet service. This paper summarizes those results that are technical in nature and that reveal the status of methanol engine technology. Specifically, results from emissions test, special lubricant tests, and cold-starting experiments are reported herein. Emissions control systems in methanol vehicles were found generally to decline somewhat in performance over time as compared to their gasoline counterpart vehicles, although this was not universally true. The severe effects on methanol engine lubricant performance resulting from cold-engine, short-trip service was demonstrated in a series of special tests of two cars, methanol and gasoline, in side-by-side service. Methanol fleet vehicles incorporated a variety of approaches to the cold-start problem -- ranging from no special engineering or systems to sophisticated systems designed to overcome the problem entirely. Cold-start systems specially designed for these vehicles did not perform as well as had been expected, probably because they were early prototype versions and were subject to some early, unforeseen problems.

  19. 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.

  20. 26 CFR 48.4041-19 - Exemption for qualified methanol and ethanol fuel.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ....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. For purposes of section 4041(b)(2) and this section, qualified methanol or ethanol fuel is liquid motor...

  1. 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....

  2. 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....

  3. 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....

  4. Spontaneous Metacognition in Rhesus Monkeys.

    PubMed

    Rosati, Alexandra G; Santos, Laurie R

    2016-09-01

    Metacognition is the ability to think about thinking. Although monitoring and controlling one's knowledge is a key feature of human cognition, its evolutionary origins are debated. In the current study, we examined whether rhesus monkeys (Macaca mulatta; N = 120) could make metacognitive inferences in a one-shot decision. Each monkey experienced one of four conditions, observing a human appearing to hide a food reward in an apparatus consisting of either one or two tubes. The monkeys tended to search the correct location when they observed this baiting event, but engaged in information seeking-by peering into a center location where they could check both potential hiding spots-if their view had been occluded and information seeking was possible. The monkeys only occasionally approached the center when information seeking was not possible. These results show that monkeys spontaneously use information about their own knowledge states to solve naturalistic foraging problems, and thus provide the first evidence that nonhumans exhibit information-seeking responses in situations with which they have no prior experience. PMID:27388917

  5. Cosmological aspects of spontaneous baryogenesis

    NASA Astrophysics Data System (ADS)

    De Simone, Andrea; Kobayashi, Takeshi

    2016-08-01

    We investigate cosmological aspects of spontaneous baryogenesis driven by a scalar field, and present general constraints that are independent of the particle physics model. The relevant constraints are obtained by studying the backreaction of the produced baryons on the scalar field, the cosmological expansion history after baryogenesis, and the baryon isocurvature perturbations. We show that cosmological considerations alone provide powerful constraints, especially for the minimal scenario with a quadratic scalar potential. Intriguingly, we find that for a given inflation scale, the other parameters including the reheat temperature, decoupling temperature of the baryon violating interactions, and the mass and decay constant of the scalar are restricted to lie within ranges of at most a few orders of magnitude. We also discuss possible extensions to the minimal setup, and propose two ideas for evading constraints on isocurvature perturbations: one is to suppress the baryon isocurvature with nonquadratic scalar potentials, another is to compensate the baryon isocurvature with cold dark matter isocurvature by making the scalar survive until the present.

  6. Spontaneous Circumrenal Hæmatoma

    PubMed Central

    Heritage, Kenneth

    1934-01-01

    By spontaneous circum-renal hæmatoma is meant a condition of extensive extravasation of blood into the kidney bed and surrounding tissues, unassociated with trauma. Since this is manifested by a fairly uniform clinical picture, by similar operative findings, and by peculiar difficulties in treatment, I propose to discuss it as a clinical entity irrespective of its wide ultimate causation. Very few cases are reported in the English literature. Nevertheless, from the world literature I have collected 170 case reports, and on them, together with three further cases, I base the present paper. Etiologically the cases fall into three groups:— (1) Those due to definite disease of the kidney or its blood-vessels, 58%. (2) Those due to extra-renal causes, 22%. (3) Those cases whose cause is obscure, 20%. In the first group neoplasms and inflammations of the kidney, aneurysms of the renal artery and arteriosclerosis are obvious causes. Many cases are due to obstruction of the renal veins. The classical triad of abdominal pain, signs of internal hæmorrhage, and a tumour in the loin are often obscured by the resemblance of an acute abdominal catastrophe. In acute cases, expectant treatment is almost invariably fatal. Evacuation of the clot, tamponage and drainage has a mortality of about 40%, whilst nephrectomy in 55 cases showed a mortality of 22%. ImagesFig. 1Fig. 2Fig. 3 PMID:19989861

  7. Clinical Manifestations of Spontaneous Pneumomediastinum

    PubMed Central

    Park, Soo Jin; Park, Ji Ye; Jung, Joonho; Park, Seong Yong

    2016-01-01

    Background Spontaneous pneumomediastinum (SPM) is an uncommon disorder with only a few reported clinical studies. The goals of this study were to investigate the clinical manifestations and the natural course of SPM, as well as examine the current available treatment options for SPM. Methods We retrospectively reviewed 91 patients diagnosed with SPM between January 2008 and June 2015. Results The mean age of the patients was 22.7±13.2 years, and 67 (73.6%) were male. Chest pain (58, 37.2%) was the predominant symptom. The most frequent precipitating factor before developing SPM was a cough (15.4%), but the majority of patients (51, 56.0%) had no precipitating factors. Chest X-ray was diagnostic in 44 patients (48.4%), and chest computed tomography (CT) showed mediastinal air in all cases. Esophagography (10, 11.0%), esophagoduodenoscopy (1, 1.1%), and bronchoscopy (5, 5.5%) were performed selectively due to clinical suspicion, but no abnormal findings that implicated organ injury were documented. Twelve patients (13.2%) were discharged after a visit to the emergency room, and the others were admitted and received conservative treatment. The mean length of hospital stay was 3.0±1.6 days. There were no complications related to SPM except for recurrence in 2 patients (2.2%). Conclusion SPM responds well to conservative treatment and follows a benign natural course. Hospitalization and aggressive treatment can be performed in selective cases. PMID:27525238

  8. Nucleosomes undergo slow spontaneous gaping.

    PubMed

    Ngo, Thuy T M; Ha, Taekjip

    2015-04-30

    In eukaryotes, DNA is packaged into a basic unit, the nucleosome which consists of 147 bp of DNA wrapped around a histone octamer composed of two copies each of the histones H2A, H2B, H3 and H4. Nucleosome structures are diverse not only by histone variants, histone modifications, histone composition but also through accommodating different conformational states such as DNA breathing and dimer splitting. Variation in nucleosome structures allows it to perform a variety of cellular functions. Here, we identified a novel spontaneous conformational switching of nucleosomes under physiological conditions using single-molecule FRET. Using FRET probes placed at various positions on the nucleosomal DNA to monitor conformation of the nucleosome over a long period of time (30-60 min) at various ionic conditions, we identified conformational changes we refer to as nucleosome gaping. Gaping transitions are distinct from nucleosome breathing, sliding or tightening. Gaping modes switch along the direction normal to the DNA plane through about 5-10 angstroms and at minutes (1-10 min) time scale. This conformational transition, which has not been observed previously, may be potentially important for enzymatic reactions/transactions on nucleosomal substrate and the formation of multiple compression forms of chromatin fibers.

  9. Spontaneous Metacognition in Rhesus Monkeys.

    PubMed

    Rosati, Alexandra G; Santos, Laurie R

    2016-09-01

    Metacognition is the ability to think about thinking. Although monitoring and controlling one's knowledge is a key feature of human cognition, its evolutionary origins are debated. In the current study, we examined whether rhesus monkeys (Macaca mulatta; N = 120) could make metacognitive inferences in a one-shot decision. Each monkey experienced one of four conditions, observing a human appearing to hide a food reward in an apparatus consisting of either one or two tubes. The monkeys tended to search the correct location when they observed this baiting event, but engaged in information seeking-by peering into a center location where they could check both potential hiding spots-if their view had been occluded and information seeking was possible. The monkeys only occasionally approached the center when information seeking was not possible. These results show that monkeys spontaneously use information about their own knowledge states to solve naturalistic foraging problems, and thus provide the first evidence that nonhumans exhibit information-seeking responses in situations with which they have no prior experience.

  10. Spontaneous formation of an "antidrop".

    PubMed

    Galvin, Kevin P; Pratten, Stephen J; Evans, Geoffrey M; Biggs, Simon

    2006-01-17

    We have observed, with great surprise, the spontaneous formation of a quite unusual drop. Because of its similarity to the antibubble [(a) Hughes, W.; Hughes, A. R. Nature 1932, 129 (3245), 59. (b) Skogen, N. Am. J. Phys. 1956, 24, 239. (c) Strong, C. L. Sci. Am. 1974, 230 (4), 116.], we describe our find as an "antidrop", a thin spherical shell of an aqueous salt solution, surrounded by an inner and outer organic liquid phase. Two of these antidrops, about 8 mm in diameter, are shown in the present paper resting on a bed of smaller conventional drops. Drops of this size do not normally appear so spherical, however the antidrop is a mere shell, and hence its geometry is dominated by the interfacial tension. We found these drops to be remarkably stable, given it was possible to reversibly deform the drops and even slice through a drop with a glass rod to produce two antidrops. Ultimately, after some finite time period, the antidrops simply disintegrated into clouds of tiny droplets of the aqueous salt solution because of the drainage and concomitant rupturing of the liquid comprising their thin spherical shells.

  11. Spontaneous Retropharyngeal and Mediastinal Emphysema.

    PubMed

    Cho, Do-Yeon; Aaron, Geoffrey P; Shepard, Kimberly G

    2016-06-01

    A 14-year-old girl with no significant medical history presented at Emergency Department with sore throat and odynophagia after one episode of nonviolent coughing. She denied any respiratory distress, voice change, foreign body ingestion, retching, substance abuse, dental procedures, or trauma. She was afebrile with normal oxygen saturation and physical examination including the head and neck was unremarkable with the exception of bilateral neck crepitus without tenderness on palpation. Fiberoptic laryngoscopy revealed a patent laryngeal airway with normal vocal fold movement. Lateral neck X-ray demonstrated a linear air-column in the retropharyngeal space and computed tomography confirmed emphysema involving the retropharyngeal space and mediastinum with no evidence of fluid collection or abscess formation. Spontaneous retropharyngeal and mediastinal emphysema are clinical entities where free air is present within the confines of retropharyngeal space and mediastinum without obvious cause. It is benign and self-limited in nature and allows for conservative management. This case is presented with a review of literature. PMID:27090269

  12. Spontaneous prosocial choice by chimpanzees

    PubMed Central

    Horner, Victoria; Carter, J. Devyn; Suchak, Malini; de Waal, Frans B. M.

    2011-01-01

    The study of human and primate altruism faces an evolutionary anomaly: There is ample evidence for altruistic preferences in our own species and growing evidence in monkeys, but one of our closest relatives, the chimpanzee (Pan troglodytes), is viewed as a reluctant altruist, acting only in response to pressure and solicitation. Although chimpanzee prosocial behavior has been reported both in observational captive studies and in the wild, thus far Prosocial Choice Tests have failed to produce evidence. However, methodologies of previous Prosocial Choice Tests may have handicapped the apes unintentionally. Here we present findings of a paradigm in which chimpanzees chose between two differently colored tokens: one “selfish” token resulting in a reward for the actor only (1/0), and the other “prosocial” token rewarding both the actor and a partner (1/1). Seven female chimpanzees, each tested with three different partners, showed a significant bias for the prosocial option. Prosocial choices occurred both in response to solicitation by the partner and spontaneously without solicitation. However, directed requests and pressure by the partner reduced the actor's prosocial tendency. These results draw into question previous conclusions indicating that chimpanzees have a limited sensitivity to the needs of others and behave prosocially only in response to significant prompting. PMID:21825175

  13. Effects of methanol vapor on human neurobehavioral measures.

    PubMed

    Cook, M R; Bergman, F J; Cohen, H D; Gerkovich, M M; Graham, C; Harris, R K; Siemann, L G

    1991-08-01

    Methanol could become an important motor fuel. The objective of this exploratory study was to provide preliminary information about whether or not acute exposure to methanol at 250 mg/m3 for 75 minutes would have adverse effects on human neurobehavioral functions important in everyday life. This concentration level was selected because it is at the upper limit of the traffic scenario estimates provided by the U.S. Environmental Protection Agency (EPA)2 (86 to 240 mg/m3), but is below the maximum concentrations for eight-hour average exposures currently recommended by the National Institute of Occupational Safety and Health (NIOSH) and the American Conference of Government and Industrial Hygienists (ACGIH) (260 mg/m3). Although traffic scenario exposure estimates suggest that such high levels of exposure last less than 15 minutes, we used a 75-minute exposure to increase the probability of identifying dependent measures that should be studied in more detail in a future confirmatory study. Twelve healthy young men, each serving as his own control, participated in two sham exposures and two methanol exposures under counterbalanced, double-blind control conditions. Because methanol is present in many foods, and because high preexposure levels of methanol or formate might obscure exposure effects, subjects were required to strictly limit their diets for 12 hours before each experimental session. The following endpoints were examined before, during, and after exposure to methanol and sham vapors: blood and urinary methanol; plasma formate; oral temperature; blood pressure; subjective mood, alertness, fatigue, workload, and symptom scales; spectral analysis of the electroencephalogram; visual- and auditory-event-related potentials; contingent negative variation; respiration; cardiac interbeat interval; Symbol Digit substitution task; three-choice reaction time; Stroop color-word test; simple reaction time; visual function; critical flicker fusion frequency; hand

  14. Physical characteristics of bright Class I methanol masers

    NASA Astrophysics Data System (ADS)

    Leurini, S.; Menten, K. M.; Walmsley, C. M.

    2016-07-01

    Context. Class I methanol masers are thought to be tracers of interstellar shock waves. However, they have received relatively little attention mostly as a consequence of their low luminosities compared to other maser transitions. This situation has changed recently and Class I methanol masers are now routinely used as signposts of outflow activity especially in high extinction regions. The recent detection of polarisation in Class I lines now makes it possible to obtain direct observational information about magnetic fields in interstellar shocks. Aims: We make use of newly calculated collisional rate coefficients for methanol to investigate the excitation of Class I methanol masers and to reconcile the observed Class I methanol maser properties with model results. Methods: We performed large velocity gradient calculations with a plane-parallel slab geometry appropriate for shocks to compute the pump and loss rates which regulate the interactions of the different maser systems with the maser reservoir. We study the dependence of the pump rate coefficient, the maser loss rate, and the inversion efficiency of the pumping scheme of several Class I masers on the physics of the emitting gas. Results: We predict inversion in all transitions where maser emission is observed. Bright Class I methanol masers are mainly high-temperature (>100 K) high-density (n(H2) ~ 107-108 cm-3) structures with methanol maser emission measures, ξ, corresponding to high methanol abundances close to the limits set by collisional quenching. Our model predictions reproduce reasonably well most of the observed properties of Class I methanol masers. Class I masers in the 25 GHz series are the most sensitive to the density of the medium and mase at higher densities than other lines. Moreover, even at high density and high methanol abundances, their luminosity is predicted to be lower than that of the 44 GHz and 36 GHz masers. Our model predictions also reflect the observational result that the

  15. Oxidation of C1 compounds by particulate fractions from Methylococcus capsulatus: properties of methanol oxidase and methanol dehydrogenase.

    PubMed Central

    Wadzinski, A M; Ribbons, D W

    1975-01-01

    Methanol (and formaldehyde) oxidizing activities in crude extracts of Methylococcus capsulatus are associated mainly with particulate fractions sedimenting between 3,000 and 40,000 X g. Most of the phenazine methosulfate (PMS)-dependent methanol (and formaldehyde) dehydrogenase activity observed resides in the soluble fraction but represents only 40% of the total (PMS dependent plus independent) activity. Both PMS-dependent methanol dehydrogenase activity and PMS-independent methanol oxidase activity are found in particulate fractions, and the PMS-dependent dehydrogenase is easily solubilized by treatment with certain phospholipases or detergents. The properties of the PMS-dependent dehydrogenase activities in the soluble fraction and that solubilized from the particles suggested that they may be identical proteins. Their pH optima, temperature dependence, thermolabilities, and sensitivities to the presence of specific antisera were indistinguishable. Homogeneous preparations of the enzyme proteins obtained from the soluble fractions of extracts and the particulate fractions solubilized by detergents had similar: (i) electrophoretic mobilities in native and denatured states (subunit size in sodium dodecyl sulfate 62,000 daltons); (ii) molecular radii under native conditions, (iii) visible absorption spectra, lambdamax 350 nm, (iv) kinetic constants for methanol and formaldehyde; (v) substrate specificity; and (vi) immunological characteristics--antisera to each enzyme preparation showed precipitin lines of identity to either of the enzymes. It is suggested that the major site of methanol and formaldehyde oxidation in M. capsulatus occurs on the intracytoplasmic membranes in vivo and is coupled to oxygen reduction. Images PMID:238947

  16. Spontaneous emission in stimulated Raman adiabatic passage

    SciTech Connect

    Ivanov, P. A.; Vitanov, N. V.; Bergmann, K.

    2005-11-15

    This work explores the effect of spontaneous emission on the population transfer efficiency in stimulated Raman adiabatic passage (STIRAP). The approach uses adiabatic elimination of weakly coupled density matrix elements in the Liouville equation, from which a very accurate analytic approximation is derived. The loss of population transfer efficiency is found to decrease exponentially with the factor {omega}{sub 0}{sup 2}/{gamma}, where {gamma} is the spontaneous emission rate and {omega}{sub 0} is the peak Rabi frequency. The transfer efficiency increases with the pulse delay and reaches a steady value. For large pulse delay and large spontaneous emission rate STIRAP degenerates into optical pumping.

  17. Herpetic viruses and spontaneous recovery in melanoma.

    PubMed

    Motofei, I G

    1996-08-01

    The malignant melanoma may display extremely variable forms of development, from clinical forms with a lethal course to the unforeseeable situations of spontaneous cures. The basic immunotherapeutic procedures, as well as hypotheses regarding the mechanisms involved in courses towards spontaneous regressions, are presented. Since viruses of the herpes genus are involved in the mechanisms assumed to be at the basis of spontaneous regressions, it is suggested that these viruses (selected strains) be used in the clinic, in order to check the advanced hypothesis, an opportunity which could permit to study also the very probable therapeutic alternative offered by this virus, namely the association of the well-known immunotherapeutic methods. PMID:8869920

  18. Antioxidant and relaxant activity of fractions of crude methanol extract and essential oil of Artemisia macrocephala jacquem

    PubMed Central

    2013-01-01

    Background The current work is an attempt to know about additional chemical profile of Artemisia macrocephala. Antioxidant activity is performed as the plant is reported to contain flavonoids, which have antioxidant activity in general. Relaxant activity of fractions of crude methanol extract is performed to know in which fraction(s) the relaxant constituents concentrate as we have already reported that its crude methanol has relaxant activity. Antispasmodic activity of essential oil is also performed as the plant is rich with essential oil. Methods Phytochemical profile of the plant is performed. Free radical scavenging activity was performed using 2, 2-diphenyl-1-picrylhydrazyl (DPPH). Relaxation activity tests of fractions and essential oil of Artemisia macrocephala were performed on sections of rabbits’ jejunum. Calcium chloride curves were constructed to investigate the mode of action of plant extracts and its essential oil. Results We detected carbohydrates, flavonoids and saponins in A. macrocephala. At concentration 0.005 mg/ml, free radical scavenging activity of ethyl acetate fraction was 121.5 ± 2.02% of ascorbic acid. n- hexane fraction relaxed spontaneous activity with EC50 0.74 ± 0.04 mg/ml. Essential oil relaxed spontaneous activity with EC50 0.8 ± 0.034 mg/ml. Chloroform and ethylacetate fractions relaxed both spontaneous and KCl-induced contractions suggesting its possible mode through calcium channels. Constructing calcium chloride curves, the test fractions showed a right shift in the EC50. Essential oil at concentration 0.1 mg/ml produced right shift with EC50 (log [Ca++]M) -2.08 ± 0.08 vs. control with EC50 -2.47 ± 0.07. The curve resembled the curves of verapamil, which caused a right shift at 0.1 μM, with EC50 -1.7 ±0.07 vs. control EC50 (log [Ca++]M) -2.45 ± 0.06. Conclusions Crude methanol and its fractions (ethyl acetate, chloroform and butanol) are rich sources of antioxidant constituents. The relaxing constituents following

  19. Photochemical reduction of carbon dioxide to methanol using ZnS microcrystallite as a photocatalyst in the presence of methanol dehydrogenase

    SciTech Connect

    Kuwabata, Susumu; Nishida, Kazufumi; Tsuda, Ryo; Inoue, Hiroshi; Yoneyama, Hiroshi . Dept. of Applied Chemistry)

    1994-06-01

    Photoinduced reduction of formate to methanol has been achieved using ZnS microcrystalline colloid which contained formate, methanol dehydrogenase (MDH), pyrroloquinoline quinone (PQQ) as an electron mediator for MDH, and 2-propanol. This reaction was combined with photoreduction of carbon dioxide to formate on the ZnS microcrystallite which had already been reported to provide a new photosynthetic route for production of methanol from carbon dioxide. The production of methanol showed a saturation tendency when it was accumulated to 0.25 mmol dm[sup [minus]3], probably due to oxidation of the produced methanol at MDH or on the ZnS photocatalyst or both. The concentration of PQQ influenced the amount of formate production but not the methanol production. The quantum efficiency obtained at 280 nm for the reduction of carbon dioxide to methanol was 5.9%, which is the highest value that has ever been reported for the photochemical reduction of carbon dioxide to methanol.

  20. The Revised Version of Class I Methanol Maser Catalog

    NASA Astrophysics Data System (ADS)

    Larionov, G. M.; Litovchenko, I. D.; Val'tts, I. E.; Alakoz, A. V.

    2011-05-01

    The revised version of the class I methanol maser catalog is presented. It contains 198 sources in total. New class I methanol masers detected in the direction of EGOs (38 sources) were added to the previous list containing ˜ 160 sources (the list have been published in the first version of this catalog - see reference in the text). Electronic version of the catalog has been generated in the form of html file - http://www.asc.rssi.ru/MMI. A statistical analysis was carried out within 2' around a maser position to find an identification of class I methanol masers with any objects typical for star-forming regions - UCHII regions, IRAS sources, dark clouds, bipolar outflows, CS lines as of dense gas tracer, and other masers (class II methanol masers, OH and H_2O). Class I methanol masers identification was made with short-wave infrared objects EGO (extended green objects), which are tracers of bipolar outflows in young stellar objects. It was shown that in the new version of catalog more than 50% of class I methanol masers are identified with bipolar outflow - given EGOs as bipolar outflows (compared with the result of 22% in the first version of the catalog that contains no information about EGO). This result is a strong evidence in favor of the fact that EGOs are indeed active bipolar outflows. At the same time it is important to note, that none of the bipolar outflow, already registered in the direction of class I methanol maser, did not coincide with EGO (with the exception of G45.47+0.07). The results are submitted in a form of a diagram.

  1. Prediction and validation of hemodialysis duration in acute methanol poisoning.

    PubMed

    Lachance, Philippe; Mac-Way, Fabrice; Desmeules, Simon; De Serres, Sacha A; Julien, Anne-Sophie; Douville, Pierre; Ghannoum, Marc; Agharazii, Mohsen

    2015-11-01

    The duration of hemodialysis (HD) in methanol poisoning (MP) is dependent on the methanol concentration, the operational parameters used during HD, and the presence and severity of metabolic acidosis. However, methanol assays are not easily available, potentially leading to undue extension or premature termination of treatment. Here we provide a prediction model for the duration of high-efficiency HD in MP. In a retrospective cohort study, we identified 71 episodes of MP in 55 individuals who were treated with alcohol dehydrogenase inhibition and HD. Four patients had residual visual abnormality at discharge and only one patient died. In 46 unique episodes of MP with high-efficiency HD the mean methanol elimination half-life (T1/2) during HD was 108 min in women, significantly different from the 129 min in men. In a training set of 28 patients with MP, using the 90th percentile of gender-specific elimination T1/2 (147 min in men and 141 min in women) and a target methanol concentration of 4 mmol/l allowed all cases to reach a safe methanol of under 6 mmol/l. The prediction model was confirmed in a validation set of 18 patients with MP. High-efficiency HD time in hours can be estimated using 3.390 × (Ln (MCi/4)) for women and 3.534 × (Ln (MCi/4)) for men, where MCi is the initial methanol concentration in mmol/l, provided that metabolic acidosis is corrected.

  2. Catalytic gasification of bagasse for the production of methanol

    SciTech Connect

    Baker, E.G.; Brown, M.D.; Robertus, R.J.

    1985-10-01

    The purpose of the study was to evaluate the technical and economic feasibility of catalytic gasification of bagasse to produce methanol. In previous studies, a catalytic steam gasification process was developed which converted wood to methanol synthesis gas in one step using nickel based catalysts in a fluid-bed gasifier. Tests in a nominal 1 ton/day process development unit (PDU) gasifier with these same catalysts showed bagasse to be a good feedstock for fluid-bed gasifiers, but the catalysts deactivated quite rapidly in the presence of bagasse. Laboratory catalyst screening tests showed K/sub 2/CO/sub 3/ doped on the bagasse to be a promising catalyst for converting bagasse to methanol synthesis gas. PDU tests with 10 wt % K/sub 2/CO/sub 3/ doped on bagasse showed the technical feasibility of this type of catalyst on a larger scale. A high quality synthesis gas was produced and carbon conversion to gas was high. The gasifier was successfully operated without forming agglomerates of catalyst, ash, and char in the gasifier. There was no loss of activity throughout the runs because catalysts is continually added with the bagasse. Laboratory tests showed about 80% of the potassium carbonate could be recovered and recycled with a simple water wash. An economic evaluation of the process for converting bagasse to methanol showed the required selling price of methanol to be significantly higher than the current market price of methanol. Several factors make this current evaluaton using bagasse as a feedstock less favorable: (1) capital costs are higher due to inflation and some extra costs required to use bagasse, (2) smaller plant sizes were considered so economies of scale are lost, and (3) the market price of methanol in the US has fallen 44% in the last six months. 24 refs., 14 figs., 16 tabs.

  3. The Methanol Poisoning Outbreaks in Libya 2013 and Kenya 2014

    PubMed Central

    Rostrup, Morten; Edwards, Jeffrey K.; Abukalish, Mohamed; Ezzabi, Masoud; Some, David; Ritter, Helga; Menge, Tom; Abdelrahman, Ahmed; Rootwelt, Rebecca; Janssens, Bart; Lind, Kyrre; Paasma, Raido; Hovda, Knut Erik

    2016-01-01

    Background Outbreaks of methanol poisoning occur frequently on a global basis, affecting poor and vulnerable populations. Knowledge regarding methanol is limited, likely many cases and even outbreaks go unnoticed, with patients dying unnecessarily. We describe findings from the first three large outbreaks of methanol poisoning where Médecins Sans Frontières (MSF) responded, and evaluate the benefits of a possible future collaboration between local health authorities, a Non-Governmental Organisation and international expertise. Methods Retrospective study of three major methanol outbreaks in Libya (2013) and Kenya (May and July 2014). Data were collected from MSF field personnel, local health personnel, hospital files, and media reports. Findings In Tripoli, Libya, over 1,000 patients were poisoned with a reported case fatality rate of 10% (101/1,066). In Kenya, two outbreaks resulted in approximately 341 and 126 patients, with case fatality rates of 29% (100/341) and 21% (26/126), respectively. MSF launched an emergency team with international experts, medications and equipment, however, the outbreaks were resolving by the time of arrival. Interpretation Recognition of an outbreak of methanol poisoning and diagnosis seem to be the most challenging tasks, with significant delay from time of first presentations to public health warnings being issued. In spite of the rapid response from an emergency team, the outbreaks were nearly concluded by the time of arrival. A major impact on the outcome was not seen, but large educational trainings were conducted to increase awareness and knowledge about methanol poisoning. Based on this training, MSF was able to send a local emergency team during the second outbreak, supporting that such an approach could improve outcomes. Basic training, simplified treatment protocols, point-of-care diagnostic tools, and early support when needed, are likely the most important components to impact the consequences of methanol poisoning

  4. Enhancing the Electrocatalytic Property of Hollow Structured Platinum Nanoparticles for Methanol Oxidation Through A Hybrid Construction

    PubMed Central

    Feng, Yan; Liu, Hui; Wang, Pengfei; Ye, Feng; Tan, Qiangqiang; Yang, Jun

    2014-01-01

    The integration of different components into a hybrid nanosystem for the utilization of the synergistic effects is an effective way to design the electrocatalysts. Herein, we demonstrate a hybrid strategy to enhance the electrocatalytic property of hollow structured Pt nanoparticles for methanol oxidation reaction. This strategy begins with the preparation of bimetallic Ag-Pt nanoparticles with a core-shell construction. Element sulfur is then added to transform the core-shell Ag-Pt nanostructures into hybrid nanodimers consisting of Ag2S nanocrystals and remaining Pt domains with intact hollow interiors (Ag2S-hPt). Finally, Au is deposited at the surface of the Ag2S domain in each hetero-dimer, resulting in the formation of ternary Ag2S-Au-hPt nanocomposites with solid-state interfaces. The ternary nanocomposites exhibit enhanced electrocatalytic property toward methanol oxidation due to the strong electronic coupling between Pt and other domains in the hybrid particles. The concept might be used toward the design and synthesis of other hetero-nanostructures with technological importance. PMID:25160947

  5. The effect of the surface composition of Ru-Pt bimetallic catalysts for methanol oxidation

    DOE PAGES

    Garrick, Taylor R.; Diao, Weijian; Tengco, John M.; Stach, Eric A.; Senanayake, Sanjaya D.; Chen, Donna A.; Monnier, John R.; Weidner, John W.

    2016-02-23

    Here, a series of Ru-Pt bimetallic catalysts prepared by the electroless deposition of controlled and variable amounts of Ru on the Pt surface of a commercially-available 20 wt% Pt/C catalyst has been characterized and evaluated for the oxidation of methanol. The activity of each Ru-Pt catalyst was determined as a function of surface composition via cyclic voltammetry. For the Ru-Pt bimetallic catalysts, activity passed through a maximum at approximately 50% monodisperse Ru surface coverage. However, due to the monolayer coverage of Ru on Pt, the amount of metal in the catalyst is minimized compared to a bulk 1:1 atomic ratiomore » of Ru:Pt seen in commercial bimetallic catalysts. Chemisorption and temperature programmed reduction experiments confirmed that the surface had characteristics of a true bimetallic catalyst. On a mass of Pt basis, the activity of this composition for methanol oxidation was 7 times higher than pure Pt and 3.5 times higher than a commercial catalyst with a 1:1 Pt:Ru bulk atomic ratio.« less

  6. Comparison of methanol and ethylene glycol oxidation by alloy and Core-Shell platinum based catalysts

    NASA Astrophysics Data System (ADS)

    Kaplan, D.; Burstein, L.; Rosenberg, Yu.; Peled, E.

    2011-10-01

    Two Core-Shell, RuCore-PtShell and IrNiCore-PtRuShell, XC72-supported catalyst were synthesized in a two-step deposition process with NaBH4 as reducing agent. The structure and composition of the Core-Shell catalysts were determined by EDS, XPS and XRD. Electrochemical characterization was performed with the use of cyclic voltammetry. Methanol and ethylene glycol oxidation activities of the Core-Shell catalysts (in terms of surface and mass activities) were studied at 80 °C and compared to those of a commercial Pt-Ru alloy catalyst. The surface activity of the alloy based catalyst, in the case of methanol oxidation, was found to be superior as a result of optimized surface Pt:Ru composition. However, the mass activity of the PtRu/IrNi/XC72 was higher than that of the alloy based catalyst by ∼50%. Regarding ethylene glycol oxidation, while the surface activity of the alloy based catalyst was slightly higher than that of the Pt/Ru/XC72 catalyst, the latter showed ∼66% higher activities in terms of A g-1 of Pt. These results show the potential of Core-Shell catalysts for reducing the cost of catalysts for DMFC and DEGFC.

  7. Coal to methanol feasiblity study: Beluga methanol project. Volume 4: Environmental

    NASA Astrophysics Data System (ADS)

    1981-09-01

    The major environmental issues relevant to development of a coal gasification and methanol fuels production facility and related coal mining activities and transportation systems in the west Cook Inlet area, Alaska were assessed. An extensive review into existing information on the Beluga region of west Cook Inlet was conducted and updated with the findings of land resource projects. Specific field activities then were initiated to expand the environmental data base in areas relevant to this project where there was a paucity of information. Based on these findings the project was reviewed in detail to identify significant environmental issues and to outline the state and federal permit requirements to ensure that these element are an integral component of all subsequent project planning and management decisions.

  8. Spontaneous network activity and synaptic development

    PubMed Central

    Kerschensteiner, Daniel

    2014-01-01

    Throughout development, the nervous system produces patterned spontaneous activity. Research over the last two decades has revealed a core group of mechanisms that mediate spontaneous activity in diverse circuits. Many circuits engage several of these mechanisms sequentially to accommodate developmental changes in connectivity. In addition to shared mechanisms, activity propagates through developing circuits and neuronal pathways (i.e. linked circuits in different brain areas) in stereotypic patterns. Increasing evidence suggests that spontaneous network activity shapes synaptic development in vivo. Variations in activity-dependent plasticity may explain how similar mechanisms and patterns of activity can be employed to establish diverse circuits. Here, I will review common mechanisms and patterns of spontaneous activity in emerging neural networks and discuss recent insights into their contribution to synaptic development. PMID:24280071

  9. Spontaneous rupture of the abdominal aorta.

    PubMed Central

    Williams, T. G.

    1977-01-01

    Fatal spontaneous rupture of the lower abdominal aorta in a previously healthy 61-year-old woman is reported; the possibility that she had the Ehlers-Danlos syndrome is discussed. Images Fig. 1 PMID:870895

  10. Spontaneous Coronary Artery Dissection with Cardiac Tamponade.

    PubMed

    Goh, Anne C H; Lundstrom, Robert J

    2015-10-01

    Spontaneous coronary artery dissection is a rare cause of acute coronary syndrome. Clinical presentation ranges from chest pain alone to ST-segment-elevation myocardial infarction, ventricular fibrillation, and sudden death. The treatment of patients with spontaneous coronary artery dissection is challenging because the disease pathophysiology is unclear, optimal treatment is unknown, and short- and long-term prognostic data are minimal. We report the case of a 70-year-old woman who presented with an acute ST-segment-elevation myocardial infarction secondary to a spontaneous dissection of the left anterior descending coronary artery. She was treated conservatively. Cardiac tamponade developed 16 hours after presentation. Repeat coronary angiography revealed extension of the dissection. Medical therapy was continued after the hemopericardium was aspirated. The patient remained asymptomatic 3 years after hospital discharge. To our knowledge, this is the first reported case of spontaneous coronary artery dissection in association with cardiac tamponade that was treated conservatively and had a successful outcome. PMID:26504447

  11. Spontaneous rupture of spleen in falciparum malaria.

    PubMed

    Vidyashankar, C; Basu, Arup; Kulkarni, A R; Choudhury, R K

    2003-01-01

    Spontaneous rupture of spleen is an extremely rare complication of falciparum malaria. We report a 3 1/2-year-old girl with splenic rupture who was managed successfully with splenectomy and antimalarials.

  12. Lunar Cycle Influences Spontaneous Delivery in Cows.

    PubMed

    Yonezawa, Tomohiro; Uchida, Mona; Tomioka, Michiko; Matsuki, Naoaki

    2016-01-01

    There is a popular belief that the lunar cycle influences spontaneous delivery in both humans and cattle. To assess this relationship, we investigated the synodic distribution of spontaneous deliveries in domestic Holstein cows. We used retrospective data from 428 spontaneous, full-term deliveries within a three-year period derived from the calving records of a private farm in Hokkaido, Japan. Spontaneous birth frequency increased uniformly from the new moon to the full moon phase and decreased until the waning crescent phase. There was a statistically significant peak between the waxing gibbous and full moon phases compared with those between the last quarter and the waning crescent. These changes were clearly observed in deliveries among multiparous cows, whereas they were not evident in deliveries among nulliparous cows. These data suggest the utility of dairy cows as models for bio-meteorological studies, and indicate that monitoring lunar phases may facilitate comprehensive understanding of parturition. PMID:27580019

  13. Lunar Cycle Influences Spontaneous Delivery in Cows

    PubMed Central

    Yonezawa, Tomohiro; Uchida, Mona; Tomioka, Michiko; Matsuki, Naoaki

    2016-01-01

    There is a popular belief that the lunar cycle influences spontaneous delivery in both humans and cattle. To assess this relationship, we investigated the synodic distribution of spontaneous deliveries in domestic Holstein cows. We used retrospective data from 428 spontaneous, full-term deliveries within a three-year period derived from the calving records of a private farm in Hokkaido, Japan. Spontaneous birth frequency increased uniformly from the new moon to the full moon phase and decreased until the waning crescent phase. There was a statistically significant peak between the waxing gibbous and full moon phases compared with those between the last quarter and the waning crescent. These changes were clearly observed in deliveries among multiparous cows, whereas they were not evident in deliveries among nulliparous cows. These data suggest the utility of dairy cows as models for bio-meteorological studies, and indicate that monitoring lunar phases may facilitate comprehensive understanding of parturition. PMID:27580019

  14. Origin of spontaneous exchange bias in Co/NiMn bilayer structure

    NASA Astrophysics Data System (ADS)

    Akbulut, A.; Akbulut, S.; Yildiz, F.

    2016-11-01

    Spontaneous exchange bias (EB) is reported for as deposited Si/Pt(tPt)/Ni45Mn55(tAFM/Co(tFM)/Pt(30 Å) thin film system without requiring any post annealing, deposition with field or field cooling procedures. Magnetic properties of this system were investigated with respect to thicknesses of buffer Pt layer (tPt), antiferromagnetic NiMn layer (tAFM) and ferromagnetic Co layer (tFM). Exchange coupling between NiMn and Co layers enhanced considerably by increasing tPt. In order to observe a spontaneous EB in the system, Pt buffer layer must be thicker than a certain thickness, and NiMn layer must be grown directly on the buffer layer. On the other hand, significant increments in the coercive fields (HC) were reported for thinner Pt buffer layers. The thickness ranges for Co and NiMn layers were also determined to obtain spontaneous EB. This spontaneous EB is discussed to be a result of NiMn (111) texture which is induced by Pt buffer layer. Greater EB fields (HEB) are measured for the samples in the negative field direction by the effect of annealing and field cooling (from 400 K to 300 K at 2 kOe).

  15. [Spontaneous resolution of a lumbar disc herniation].

    PubMed

    Gelabert-González, M; Serramito-García, R; Aran-Echabe, E; García-Allut, A

    2007-04-01

    Lumbar disc herniation is a common cause of lower leg radiculopathy and the most effective methods of treatment remain in question. Both surgical and nonsurgical treatments may provide a successful outcome in appropriately selected patients. The spontaneous resolution of herniated lumbar discs is a well-established phenomenon. The authors present a case of spontaneous regression of a herniated lumbar nucleus pulpous in a patient with radiculopathy. PMID:17497061

  16. Spontaneous fission of 256Rf, new data

    NASA Astrophysics Data System (ADS)

    Svirikhin, A. I.; Yeremin, A. V.; Izosimov, I. N.; Isaev, A. V.; Kuznetsov, A. N.; Malyshev, O. N.; Popeko, A. G.; Popov, Yu. A.; Sokol, E. A.; Chelnokov, M. L.; Chepigin, V. I.; Andel, B.; Asfari, M. Z.; Gall, B.; Yoshihiro, N.; Kalaninova, Z.; Mullins, S.; Piot, J.; Stefanova, E.; Tonev, D.

    2016-07-01

    Spontaneous fission properties of the short-lived neutron-deficient 256Rf nucleus produced in the complete fusion reaction with a beam of multiply charged heavy 50Ti ions from the U-400 cyclotron (FLNR, JINR) are experimentally investigated. Its half-life and decay branching ratio are measured. The average number of neutrons per spontaneous fission of 256Rf (bar v = 4.47 ± 0.09) is determined for the first time.

  17. Filum ependymoma mimicking spontaneous intracranial hypotension.

    PubMed

    Schievink, Wouter I; Akopov, Sergey E

    2005-05-01

    A 34-year-old man with a 2-week history of orthostatic headaches and a "dry tap" at lumbar puncture was found to have a lumbar intradural mass on magnetic resonance imaging (MRI) examination. A myxopapillary ependymoma was resected and the patient's headache completely resolved. The combination of spontaneous orthostatic headaches and a "dry tap" at the time of lumbar puncture does not always indicate the presence of a spontaneous cerebrospinal fluid (CSF) leak and intracranial hypotension. PMID:15953283

  18. Multiple spontaneous visceral hematomas revealing polyarteritis nodosa.

    PubMed

    Allanore, Yannick; Rosenberg, Carole; Vignaux, Olivier; Legmann, Paul; Kanev, K; Menkes, Charles J; Kahan, Andre

    2004-09-01

    Polyarteritis nodosa is a rare life-threatening disease characterized by necrotizing vasculitis of small and median arteries. We describe the exceptional case of a 28-year-old man with successive spontaneous visceral hematomas of the kidney, bladder, and liver. Arteriography was performed for a recent spontaneous hepatic hematoma and a microaneurysm was detected, allowing the diagnosis of polyarteritis nodosa and prescription of appropriate treatment.

  19. FEL gain optimisation and spontaneous radiation

    SciTech Connect

    Bali, L.M.; Srivastava, A.; Pandya, T.P.

    1995-12-31

    Colson have evaluated FEL gains for small deviations from perfect electron beam injection, with radiation of the same polarisation as that of the wiggler fields. We find that for optimum gain the polarisation of the optical field should be the same as that of the spontaneous emission under these conditions. With a helical wiggler the axial oscillations resulting from small departures from perfect electron beam injection lead to injection dependent unequal amplitudes and phases of the spontaneous radiation in the two transverse directions. Viewed along the axis therefore the spontaneous emission is elliptically polarised. The azimuth of the ellipse varies with the difference of phase of the two transverse components of spontaneous emission but the eccentricity remains the same. With planar wigglers the spontaneous emission viewed in the axial direction is linearly polarised, again with an injection dependent azimuth. For optimum coherent gain of a radiation field its polarisation characteristics must be the same as those of the spontaneous radiation with both types of wiggler. Thus, with a helical wiggler and the data reported earlier, an increase of 10% in the FEL gain at the fundamental frequency and of 11% at the fifth harmonic has been calculated in the small gain per pass limit. Larger enhancements in gain may result from more favourable values of input parameters.

  20. Spontaneous vesicle recycling in the synaptic bouton.

    PubMed

    Truckenbrodt, Sven; Rizzoli, Silvio O

    2014-01-01

    The trigger for synaptic vesicle exocytosis is Ca(2+), which enters the synaptic bouton following action potential stimulation. However, spontaneous release of neurotransmitter also occurs in the absence of stimulation in virtually all synaptic boutons. It has long been thought that this represents exocytosis driven by fluctuations in local Ca(2+) levels. The vesicles responding to these fluctuations are thought to be the same ones that release upon stimulation, albeit potentially triggered by different Ca(2+) sensors. This view has been challenged by several recent works, which have suggested that spontaneous release is driven by a separate pool of synaptic vesicles. Numerous articles appeared during the last few years in support of each of these hypotheses, and it has been challenging to bring them into accord. We speculate here on the origins of this controversy, and propose a solution that is related to developmental effects. Constitutive membrane traffic, needed for the biogenesis of vesicles and synapses, is responsible for high levels of spontaneous membrane fusion in young neurons, probably independent of Ca(2+). The vesicles releasing spontaneously in such neurons are not related to other synaptic vesicle pools and may represent constitutively releasing vesicles (CRVs) rather than bona fide synaptic vesicles. In mature neurons, constitutive traffic is much dampened, and the few remaining spontaneous release events probably represent bona fide spontaneously releasing synaptic vesicles (SRSVs) responding to Ca(2+) fluctuations, along with a handful of CRVs that participate in synaptic vesicle turnover.

  1. Spontaneous Gastric Perforation in Two Adolescents

    PubMed Central

    Akalonu, Amaka; Yasrebi, Mona; Rios, Zarela Molle

    2016-01-01

    Case series Patients: Female, 11 • Male, 15 Final Diagnosis: Spontaneous gastric perforation Symptoms: Abdominal pain • distention • vomiting • leukocytosis Medication: — Clinical Procedure: Both patients had surgery Specialty: Gastroenterology Objective: Rare etiology Background: Spontaneous gastric perforation is a rare clinical disorder. The majority of the available data have been reported in the neonatal age group. There are a few cases of spontaneous gastric perforation in preschool children. To our knowledge, there is no published information on spontaneous gastric perforation in older children and adolescents. Case Report: We describe the presentation and clinical course of two adolescent children who presented with spontaneous gastric perforation. Both children presented with acute onset abdominal pain, which progressively worsened. In both cases, the patient were taken urgently to the operating room after imaging studies had shown pneumoperitoneum. In both cases, surgery revealed gastric perforation with no obvious etiology, specifically no ulcer, inflammation, or other pathology. Conclusions: These two cases highlight the importance of including spontaneous gastric perforation, not just the typical duodenal/gastric ulcer, in the differential of a patient with severe abdominal pain and distension, who has imaging showing pneumoperitoneum. PMID:27686129

  2. Toddlers infer unobserved causes for spontaneous events

    PubMed Central

    Muentener, Paul; Schulz, Laura

    2014-01-01

    Previous research suggests that children infer the presence of unobserved causes when objects appear to move spontaneously. Are such inferences limited to motion events or do children assume that unexplained physical events have causes more generally? Here we introduce an apparently spontaneous event and ask whether, even in the absence of spatiotemporal and co-variation cues linking the events, toddlers treat a plausible variable as a cause of the event. Toddlers (24 months) saw a toy that appeared to light up either spontaneously or after an experimenter’s action. Toddlers were also introduced to a button but were not shown any predictive relation between the button and the light. Across three different dependent measures of exploration, predictive looking (Study 1), prompted intervention (Study 2), and spontaneous exploration (Study 3), toddlers were more likely to represent the button as a cause of the light when the event appeared to occur spontaneously. In Study 4, we found that even in the absence of a plausible candidate cause, toddlers engaged in selective exploration when the light appeared to activate spontaneously. These results suggest that toddlers’ exploration is guided by the causal explanatory power of events. PMID:25566161

  3. Informational Constraints on Spontaneous Visuomotor Entrainment

    PubMed Central

    Varlet, Manuel; Bucci, Colleen; Richardson, Michael J.; Schmidt, R. C.

    2015-01-01

    Past research has revealed that an individual's rhythmic limb movements become spontaneously entrained to an environmental rhythm if visual information about the rhythm is available and its frequency is near that of the individual's movements. Research has also demonstrated that if the eyes track an environmental stimulus, the spontaneous entrainment to the rhythm is strengthened. One hypothesis explaining this enhancement of spontaneous entrainment is that the limb movements and eye movements are linked through a neuromuscular coupling or synergy. Another is that eye-tracking facilitates the pick up of important coordinating information. Experiment 1 investigated the first hypothesis by evaluating whether any rhythmic movement of the eyes would facilitate spontaneous entrainment. Experiment 2 and 3 (respectively) explored whether eye-tracking strengthens spontaneous entrainment by allowing the pickup of trajectory direction change information or allowing an increase in the amount of information to be picked-up. Results suggest that the eye-tracking enhancement of spontaneous entrainment is a consequence of increasing the amount of information available to be picked-up. PMID:25866944

  4. Supercritical fluid extraction of vapor-deposited pyrene from carbonaceous coal stack ash.

    PubMed

    Mauldin, R F; Vienneau, J M; Wehry, E L; Mamantov, G

    1990-11-01

    The efficiencies of extraction of vapor-deposited pyrene from a high-carbon coal stack ash by Soxhlet extraction with methanol, ultrasonic extraction with toluene, acid pretreatment and subsequent ultrasonic extraction with toluene, batch extraction with toluene, and supercritical fluid extraction (SFE) are compared. SFE using CO(2) or isobutane yielded extraction recoveries virtually identical with those obtained using ultrasonic or Soxhlet extraction processes. Collection of the SFE extract was performed by expansion into a solvent or onto the head of a gas chromatography (GC) column. No loss of extracted pyrene was observed upon collection of methanol-modified CO(2) SFE by expansion into methanol. Also, no loss of pure CO(2) SFE extract was observed upon collection on the head of a GC column. However, use of a methanol or toluene modifier for CO(2) SFE directly coupled to GC effected complete loss of extracted pyrene.

  5. Spontaneous resolution of multiple nodular pulmonary AA amyloidosis.

    PubMed

    Fukatsu, Hirotoshi; Miyoshi, Haruka; Ishiki, Kuniharu

    2010-01-01

    A 62-year-old man presented with a two-week history of dry cough. A chest computed tomography (CT) showed three nodular masses of soft tissue density without calcification or cavitary formation in the right lung. F-18 fluorodeoxyglucose PET/CT scan revealed high FDG uptake in two out of three pulmonary nodules. Transbronchial lung biopsy specimens consisted of amorphous eosinophilic deposits that were demonstrated to be amyloid because they were positive for Congo Red staining. After oxidation with permanganate solution, the Congo Red staining disappeared, indicating that this amyloid was amyloid A protein-derived type. There was no evidence of any systemic diseases. We diagnosed the patient as having multiple nodular pulmonary AA amyloidosis. The patient was conservatively managed without treatment, and the pulmonary nodules disappeared spontaneously three months later. PMID:21048364

  6. Bifunctional Anode Catalysts for Direct Methanol Fuel Cells

    SciTech Connect

    Rossmeisl, Jan; Ferrin, Peter A.; Tritsaris, Georgios A.; Nilekar, Anand U.; Koh, Shirlaine; Bae, Sang Eun; Brankovic, Stanko R.; Strasser, Peter; Mavrikakis, Manos

    2012-06-13

    Using the binding energy of OH* and CO* on close-packed surfaces as reactivity descriptors, we screen bulk and surface alloy catalysts for methanol electro-oxidation activity. Using these two descriptors, we illustrate that a good methanol electro-oxidation catalyst must have three key properties: (1) the ability to activate methanol, (2) the ability to activate water, and (3) the ability to react off surface intermediates (such as CO* and OH*). Based on this analysis, an alloy catalyst made up of Cu and Pt should have a synergistic effect facilitating the activity towards methanol electro-oxidation. Using these two reactivity descriptors, a surface PtCu3 alloy is proposed to have the best catalytic properties of the Pt–Cu model catalysts tested, similar to those of a Pt–Ru bulk alloy. To validate the model, experiments on a Pt(111) surface modified with different amounts of Cu adatoms are performed. Adding Cu to a Pt(111) surface increases the methanol oxidation current by more than a factor of three, supporting our theoretical predictions for improved electrocatalysts.

  7. Sulfur removal from diesel fuel-contaminated methanol.

    SciTech Connect

    Lee, S. H. D.; Kumar, R.; Krumpelt, M.; Chemical Engineering

    2002-03-01

    Methanol is considered to be a potential on-board fuel for fuel cell-powered vehicles. In current distribution systems for liquid fuels used in the transportation sector, commodity methanol can occasionally become contaminated with the sulfur in diesel fuel or gasoline. This sulfur would poison the catalytic materials used in fuel reformers for fuel cells. We tested the removal of this sulfur by means of ten activated carbons (AC) that are commercially available. Tests were conducted with methanol doped with 1 vol.% grade D-2 diesel fuel containing 0.29% sulfur, which was present essentially as 33-35 wt.% benzothiophenes (BTs) and 65-67 wt.% dibenzothiophenes (DBT). In general, coconut shell-based carbons activated by high-temperature steam were more effective at sulfur removal than coal-based carbons. Equilibrium sorption data showed linear increase in sulfur capture with the increase of sulfur concentration in methanol. Both types of carbons had similar breakthrough characteristics, with the dynamic sorption capacity of each being about one-third of its equilibrium sorption capacity. Results of this study suggest that a fixed-bed sorber of granular AC can be used, such as in refueling stations, for the removal of sulfur in diesel fuel-contaminated methanol.

  8. Performance of direct methanol polymer electrolyte fuel cell

    SciTech Connect

    Shin, Dong Ryul; Jung, Doo Hwan; Lee, Chang Hyeong; Chun, Young Gab

    1996-12-31

    Direct methanol fuel cells (DMFC) using polymer electrolyte membrane are promising candidate for application of portable power sources and transportation applications because they do not require any fuel processing equipment and can be operated at low temperature of 60{degrees}C - 130{degrees}C. Elimination of the fuel processor results in simpler design, higher operation reliability, lower weight volume, and lower capital and operating cost. However, methanol as a fuel is relatively electrochemical inert, so that kinetics of the methanol oxidation is too slow. Platinum and Pt-based binary alloy electrodes have been extensively studied for methanol electro-oxidation in acid electrolyte at ambient and elevated temperatures. Particularly, unsupported carbon Pt-Ru catalyst was found to be superior to the anode of DMFC using a proton exchange membrane electrolyte (Nafion). The objective of this study is to develop the high performance DNTC. This paper summarizes the results from half cell and single cell tests, which focus on the electrode manufacturing process, catalyst selection, and operating conditions of single cell such as methanol concentration, temperature and pressure.

  9. Methanol Uptake By Low Temperature Aqueous Sulfuric Acid Solutions

    NASA Technical Reports Server (NTRS)

    Iraci, Laura T.; Essin, Andrew M.; Golden, David M.; Hipskind, R. Stephen (Technical Monitor)

    2001-01-01

    To evaluate the role of upper tropospheric and lower stratospheric aerosols in the global budget of methanol, the solubility and reactivity of CH3OH in aqueous sulfuric acid solutions are under investigation. Using standard uptake techniques in a Knudsen cell reactor, we have measured the effective Henry's law coefficient, H(*), for methanol dissolution into 45 to 70 percent by weight H2SO4. We find that methanol solubility ranges from 10(exp 5) to 10(exp 8) M/atm and increases with decreasing temperature and with increasing sulfuric acid content. These solubility measurements include uptake due to physical solvation and all rapid equilibria which are established in solution. Our data indicate that simple uptake by aqueous sulfuric acid particles will not be a significant sink for methanol in the UT/LS. These results differ from those recently reported in the literature, and an explanation of this disparity will be presented. In addition to solvation, 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 may proceed in the atmosphere but is not significant under our experimental conditions. Results obtained using a complementary equilibrium measurement technique confirm this directly. In addition, the extent of methanol sequestration via formation of mono- and dimethylsulfate will be evaluated under several atmospheric conditions.

  10. Exergy analysis of polymer electrolyte fuel cell systems using methanol

    NASA Astrophysics Data System (ADS)

    Ishihara, Akimitsu; Mitsushima, Shigenori; Kamiya, Nobuyuki; Ota, Ken-ichiro

    An exergy (available energy) analysis has been conducted on a typical polymer electrolyte fuel cell (PEFC) system using methanol. The material balance and enthalpy balance were calculated for the PEFC system using methanol steam reforming, and the exergy flow was obtained. Based on these results, the exergy loss in each unit was obtained, and the difference between the enthalpy and exergy was discussed. The exergy loss in this system was calculated to be 193 kJ/mol MeOH for the steam reforming process of methanol. Although the enthalpy efficiency approached unity as the recovery rate of the waste heat from the cell approached unity, the exergy efficiency remained around 0.45 since the cell's operating temperature of 80 °C is low. It was also found that the cell voltage should exceed 0.82 V in order to obtain the exergy efficiency of 0.5 or higher. A direct methanol fuel cell (DMFC) was analyzed using the exergy and compared with the methanol reforming PEFC. In order to obtain the exergy efficiency higher than that of PEFC with steam reforming, the cell voltage of the DMFC should be 0.50 V or larger at the current density of 600 mA/cm 2.

  11. Process conditions for preparing methanol from cornstalk gas.

    PubMed

    Zhu, Ling-Feng; Du, Lei; Li, Xin-Bao; Li, Guo-Ting; Zhang, Jie

    2007-01-01

    The low-heat-value cornstalk gas produced in the down-flow fixed bed gasifier was tentatively used for methanol synthesis. The cornstalk gas was purified and the technical procedures such as deoxygenation, desulfurization, catalytic cracking of tar, purification and hydrogenation were studied. The catalytic experiments of methanol synthesis with cornstalk syngas were carried out in a tubular-flow integral and isothermal reactor. The effect of reaction temperature, pressure, catalyst types, catalyst particle size, syngas flow at entering end and composition of syngas was investigated. The optimum process conditions and yield of methanol from cornstalk syngas were obtained. The experimental results indicated that the proper catalyst for the synthetic reaction was C301 and the optimum catalyst size was 0.833 mm x 0.351 mm. The optimum operating temperature and pressure were found to be 235 degrees C and 5 MPa, respectively. The suitable syngas flow 0.9-1.10 mol/h at entering end was selected and the best composition of syngas were CO 10.49%, CO2 8.8%, N2 37.32%, C(n)H(m) 0.95% and H2 40.49%. The best methanol yield was 0.418 g/g cornstalk. This study provided the technical support for the industrial test of methanol production from biomass (cornstalk) gas.

  12. Low Crossover Polymer Electrolyte Membranes for Direct Methanol Fuel Cells

    NASA Technical Reports Server (NTRS)

    Prakash, G. K. Surya; Smart, Marshall; Atti, Anthony R.; Olah, George A.; Narayanan, S. R.; Valdez, T.; Surampudi, S.

    1996-01-01

    Direct Methanol Fuel Cells (DMFC's) using polymer electrolyte membranes are promising power sources for portable and vehicular applications. State of the art technology using Nafion(R) 117 membranes (Dupont) are limited by high methanol permeability and cost, resulting in reduced fuel cell efficiencies and impractical commercialization. Therefore, much research in the fuel cell field is focused on the preparation and testing of low crossover and cost efficient polymer electrolyte membranes. The University of Southern California in cooperation with the Jet Propulsion Laboratory is focused on development of such materials. Interpenetrating polymer networks are an effective method used to blend polymer systems without forming chemical links. They provide the ability to modify physical and chemical properties of polymers by optimizing blend compositions. We have developed a novel interpenetrating polymer network based on poly (vinyl - difluoride)/cross-linked polystyrenesulfonic acid polymer composites (PVDF PSSA). Sulfonation of polystyrene accounts for protonic conductivity while the non-polar, PVDF backbone provides structural integrity in addition to methanol rejection. Precursor materials were prepared and analyzed to characterize membrane crystallinity, stability and degree of interpenetration. USC JPL PVDF-PSSA membranes were also characterized to determine methanol permeability, protonic conductivity and sulfur distribution. Membranes were fabricated into membrane electrode assemblies (MEA) and tested for single cell performance. Tests include cell performance over a wide range of temperatures (20 C - 90 C) and cathode conditions (ambient Air/O2). Methanol crossover values are measured in situ using an in-line CO2 analyzer.

  13. Effect of cobalt on the anaerobic thermophilic conversion of methanol.

    PubMed

    Paulo, Paula L; Jiang, Bo; Cysneiros, Denise; Stams, Alfons J M; Lettinga, Gatze

    2004-02-20

    The importance of cobalt on the anaerobic conversion of methanol under thermophilic conditions was studied in three parallel lab-scale UASB-reactors and in cobalt-limited enriched cultures. Reactors R1, R2, and R3 were fed with methanol in a bicarbonate-buffered medium, supplied with iron and macronutrients: in R1 all metals were supplied (control), R2 was cobalt deprived, and in R3 all metals were deprived. In the 136 days of continuous experiment, a drop in performance was observed over the last 30 days. Particularly in R3, both methanol removal and methane formation dropped by 7.1% and 13.7%, respectively, compared to the control reactor, R1. When the medium was cobalt-deprived, acetate was not produced and, as a consequence, the enriched consortium lost its capacity to degrade acetate, indicating that the acetotrophic microorganisms were washed out. The addition of 0.5 microM of cobalt to a cobalt-deprived enrichment culture led to acetate accumulation. The results obtained in this study indicate that the mixed consortium requires a proper amount of cobalt, and its addition to a concentration of 0.1 microM leads to the highest methanol conversion rate, with methane as the sole end product from methanol.

  14. Hydrogen bond competition in the ethanol-methanol dimer.

    PubMed

    Finneran, Ian A; Carroll, P Brandon; Mead, Griffin J; Blake, Geoffrey A

    2016-08-10

    Previous theoretical work on the ethanol-methanol dimer has been inconclusive in predicting the preferred hydrogen bond donor/acceptor configuration. Here, we report the microwave spectrum of the dimer using a chirped pulse Fourier transform microwave spectrometer from 8-18 GHz. In an argon-backed expansion, 50 transitions have been assigned to a trans-ethanol-acceptor/methanol-donor structure that is likely stabilized by a secondary weak C-HO hydrogen bond. A higher energy conformer was observed in a helium-backed expansion and tentatively assigned to a gauche-ethanol-acceptor/methanol-donor structure. No ethanol-donor/methanol-acceptor dimers have been found, suggesting such interactions are energetically disfavored. A preliminary analysis of the A-E splitting due to the internal rotation of the methanol methyl group in the ground state species is also presented. We find evidence of the Ubbelohde effect in the measured A-E splittings of three deuterated isotopologues and the normal species of this conformer. PMID:27472828

  15. Frequencies of spontaneous breast development and spontaneous menarche in Turner syndrome in Japan.

    PubMed

    Tanaka, Toshiaki; Igarashi, Yutaka; Ozono, Keiichi; Ohyama, Kenji; Ogawa, Masamichi; Osada, Hisao; Onigata, Kazumichi; Kanzaki, Susumu; Kohno, Hitoshi; Seino, Yoshiki; Takahashi, Hiroaki; Tajima, Toshihiro; Tachibana, Katsuhiko; Tanaka, Hiroyuki; Nishi, Yoshikazu; Hasegawa, Tomonobu; Fujita, Keinosuke; Yorifuji, Tohru; Horikawa, Reiko; Yokoya, Susumu

    2015-10-01

    The Growject® database on human GH treatment in Turner syndrome was analyzed in the Turner Syndrome Research Collaboration, and the relationships of the frequencies of spontaneous breast development and spontaneous menarche with karyotype and GH treatment were investigated. One hundred and three cases started GH treatment with 0.5 IU/kg/ week (0.5 IU group), and their dose was increased to 0.35 mg/kg/wk midway through the treatment course. Another 109 cases started GH at a dose of 0.35 mg/kg/wk (0.35 mg group). Spontaneous breast development was observed in 77 (36.3%) of the 212 patients, and spontaneous menarche occurred in 31 patients (14.6%). The frequency of spontaneous breast development was significantly lower in patients with the 45,X karyotype and significantly higher in patients with a structural abnormality of the second X chromosome. The frequency of spontaneous menarche was significantly higher in patients with mosaicism characterized by X monosomy and a cellular line with no structural abnormality of the X chromosome. No significant differences in frequencies of spontaneous breast development and spontaneous menarche were observed between the two dose groups, indicating that GH treatment does not increase the frequency of spontaneous puberty.

  16. Frequencies of spontaneous breast development and spontaneous menarche in Turner syndrome in Japan.

    PubMed

    Tanaka, Toshiaki; Igarashi, Yutaka; Ozono, Keiichi; Ohyama, Kenji; Ogawa, Masamichi; Osada, Hisao; Onigata, Kazumichi; Kanzaki, Susumu; Kohno, Hitoshi; Seino, Yoshiki; Takahashi, Hiroaki; Tajima, Toshihiro; Tachibana, Katsuhiko; Tanaka, Hiroyuki; Nishi, Yoshikazu; Hasegawa, Tomonobu; Fujita, Keinosuke; Yorifuji, Tohru; Horikawa, Reiko; Yokoya, Susumu

    2015-10-01

    The Growject® database on human GH treatment in Turner syndrome was analyzed in the Turner Syndrome Research Collaboration, and the relationships of the frequencies of spontaneous breast development and spontaneous menarche with karyotype and GH treatment were investigated. One hundred and three cases started GH treatment with 0.5 IU/kg/ week (0.5 IU group), and their dose was increased to 0.35 mg/kg/wk midway through the treatment course. Another 109 cases started GH at a dose of 0.35 mg/kg/wk (0.35 mg group). Spontaneous breast development was observed in 77 (36.3%) of the 212 patients, and spontaneous menarche occurred in 31 patients (14.6%). The frequency of spontaneous breast development was significantly lower in patients with the 45,X karyotype and significantly higher in patients with a structural abnormality of the second X chromosome. The frequency of spontaneous menarche was significantly higher in patients with mosaicism characterized by X monosomy and a cellular line with no structural abnormality of the X chromosome. No significant differences in frequencies of spontaneous breast development and spontaneous menarche were observed between the two dose groups, indicating that GH treatment does not increase the frequency of spontaneous puberty. PMID:26568657

  17. Frequencies of spontaneous breast development and spontaneous menarche in Turner syndrome in Japan

    PubMed Central

    Tanaka, Toshiaki; Igarashi, Yutaka; Ozono, Keiichi; Ohyama, Kenji; Ogawa, Masamichi; Osada, Hisao; Onigata, Kazumichi; Kanzaki, Susumu; Kohno, Hitoshi; Seino, Yoshiki; Takahashi, Hiroaki; Tajima, Toshihiro; Tachibana, Katsuhiko; Tanaka, Hiroyuki; Nishi, Yoshikazu; Hasegawa, Tomonobu; Fujita, Keinosuke; Yorifuji, Tohru; Horikawa, Reiko; Yokoya, Susumu

    2015-01-01

    Abstract. The Growject® database on human GH treatment in Turner syndrome was analyzed in the Turner Syndrome Research Collaboration, and the relationships of the frequencies of spontaneous breast development and spontaneous menarche with karyotype and GH treatment were investigated. One hundred and three cases started GH treatment with 0.5 IU/kg/ week (0.5 IU group), and their dose was increased to 0.35 mg/kg/wk midway through the treatment course. Another 109 cases started GH at a dose of 0.35 mg/kg/wk (0.35 mg group). Spontaneous breast development was observed in 77 (36.3%) of the 212 patients, and spontaneous menarche occurred in 31 patients (14.6%). The frequency of spontaneous breast development was significantly lower in patients with the 45,X karyotype and significantly higher in patients with a structural abnormality of the second X chromosome. The frequency of spontaneous menarche was significantly higher in patients with mosaicism characterized by X monosomy and a cellular line with no structural abnormality of the X chromosome. No significant differences in frequencies of spontaneous breast development and spontaneous menarche were observed between the two dose groups, indicating that GH treatment does not increase the frequency of spontaneous puberty. PMID:26568657

  18. Dynamics of spontaneous otoacoustic emissions

    NASA Astrophysics Data System (ADS)

    Bergevin, Christopher; Salerno, Anthony

    2015-12-01

    Spontaneous otoacoustic emissions (SOAEs) have become a hallmark feature in modern theories of an `active' inner ear, given their numerous correlations to auditory function (e.g., threshold microstructure, neurophysiological tuning curves), near universality across tetrapod classes, and physiological correlates at the single hair cell level. However, while several different classes of nonlinear models exist that describe the mechanisms underlying SOAE generation (e.g., coupled limit-cycle oscillators, global standing waves), there is still disagreement as to precisely which biophysical concepts are at work. Such is further compounded by the idiosyncratic nature of SOAEs: Not all ears emit, and when present, SOAE activity can occur at seemingly arbitrary frequencies (though always within the most sensitive range of the audiogram) and in several forms (e.g., peaks, broad `baseline' plateaus). The goal of the present study was to develop new signal processing and stimulation techniques that would allow for novel features of SOAE activity to be revealed. To this end, we analyzed data from a variety of different species: human, lizard, and owl. First, we explored several strategies for examining SOAE waveforms in the absence of external stimuli to further ascertain what constitutes `self-sustained sinusoids' versus `filtered noise'. We found that seemingly similar peaks in the spectral domain could exhibit key differences in the time domain, which we interpret as providing critical information about the underlying oscillators and their coupling. Second, we introduced dynamic stimuli (swept-tones, tone bursts) at a range of levels, whose interaction with SOAEs could be visualized in the time-frequency domain. Aside from offering a readily accessible way to visualize many previously reported effects (e.g., entrainment, facilitation), we observed several new features such as subharmonic distortion generation and competing pulling/pushing effects when multiple tones were

  19. Quenching Phase Separation by Vapor Deposition Polymerization

    NASA Astrophysics Data System (ADS)

    Tao, Ran; Anthamatten, Mitchell

    2015-03-01

    Initiated chemical vapor deposition (iCVD) is a solventless, free radical technique predominately used to deposit homogeneous films of linear and crosslinked polymers directly from gas phase feeds. We report a template-free method to fabricate continuous-phase porous polymer films by simultaneous phase separation during iCVD. Phase separation during film growth is achieved by condensing an inert porogen, along with initiator, monomer, and crosslinker. When the vapor mixture transports to the cooled substrate, phase separation occurs along with polymerization and crosslinking, which quench the state of phase separation. The kinetics of spontaneously phase separation can be qualitatively understood on the basis of Cahn-Hilliard theory. A series of films were grown by varying monomer and porogen's degree of saturation. Deposited films were studied by electron microscopy and spectroscopic techniques.

  20. Mind the gap: a case of severe methanol intoxication.

    PubMed

    Nazir, Salik; Melnick, Stephen; Ansari, Shabana; Kanneh, Haitham T

    2016-01-01

    We report a case of a 37-year-old woman with non-insulin-dependent diabetes on sitagliptin, an alcohol abuser who was brought unresponsive to the emergency department of our hospital. On arrival, the patient was intubated and mechanically ventilated due to a low Glasgow Coma score of 3/15. Initial laboratory testing identified profound high anion gap metabolic acidosis. Owing to the dubious circumstances and the depth of acidosis, methanol and ethylene glycol intoxication was suspected. Further evaluation revealed a significantly increased serum osmolal gap. Pending volatile compound screen, fomepizole was started and urgent haemodialysis undertaken. Subsequent brain MRI identified changes in putamen of bilateral basal ganglia, suggestive of methanol intoxication. The patient was later found to have an initial methanol level of 237 mg/dL. She was successfully extubated on day 2 of hospitalisation, with residual cognitive and visual deficits.

  1. Commercialization of a direct methanol fuel cell system

    NASA Astrophysics Data System (ADS)

    Halpert, G.; Narayanan, S. R.; Frank, H.; Kindler, A.; Valdez, T.; Chun, W.; Surampudi, S.

    1997-01-01

    This paper describes a major breakthrough in energy technology developed at the Jet Propulsion Laboratory that can be used in a wide variety of portable, remote and transportation applications without polluting the environment. The status, performance, and design considerations of the JPL non-polluting, Direct Methanol, Fuel Cell system for consumer equipment and transportation applications are reported herein. This new fuel cell technology utilizes the direct oxidation of a 3% aqueous liquid methanol solution as the fuel and air (O2) as the oxidant. The only products are CO2 and water. Therefore, because recharging can be accomplished by refueling with methanol, vehicles can enjoy unlimited range and extended use compared to battery operated devices requiring recharge time and power accessibility.

  2. Mind the gap: a case of severe methanol intoxication.

    PubMed

    Nazir, Salik; Melnick, Stephen; Ansari, Shabana; Kanneh, Haitham T

    2016-01-01

    We report a case of a 37-year-old woman with non-insulin-dependent diabetes on sitagliptin, an alcohol abuser who was brought unresponsive to the emergency department of our hospital. On arrival, the patient was intubated and mechanically ventilated due to a low Glasgow Coma score of 3/15. Initial laboratory testing identified profound high anion gap metabolic acidosis. Owing to the dubious circumstances and the depth of acidosis, methanol and ethylene glycol intoxication was suspected. Further evaluation revealed a significantly increased serum osmolal gap. Pending volatile compound screen, fomepizole was started and urgent haemodialysis undertaken. Subsequent brain MRI identified changes in putamen of bilateral basal ganglia, suggestive of methanol intoxication. The patient was later found to have an initial methanol level of 237 mg/dL. She was successfully extubated on day 2 of hospitalisation, with residual cognitive and visual deficits. PMID:26917798

  3. Catalytic partial oxidation of methanol and ethanol for hydrogen generation.

    PubMed

    Hohn, Keith L; Lin, Yu-Chuan

    2009-01-01

    Hydrogen-powered fuel cell vehicles feature high energy efficiency and minor environmental impact. Liquid fuels are ideal hydrogen carriers, which can catalytically be converted into syngas or hydrogen to power vehicles. Among the potential liquid fuels, alcohols have several advantages. The hydrogen/carbon ratio is higher than that of other liquid hydrocarbons or oxygenates, especially in the case of methanol. In addition, alcohols can be derived from renewable biomass resources. Catalytic partial oxidation of methanol or ethanol offers immense potential for onboard hydrogen generation due to its rapid reaction rate and exothermic nature. These benefits stimulate a burgeoning research community in catalyst design, reaction engineering, and mechanistic investigation. The purpose of this Minireview is to provide insight into syngas and hydrogen production from methanol and ethanol partial oxidation, particularly highlighting catalytic chemistry.

  4. Structure and energetics of hydrogen-bonded networks of methanol on close packed transition metal surfaces

    NASA Astrophysics Data System (ADS)

    Murphy, Colin J.; Carrasco, Javier; Lawton, Timothy J.; Liriano, Melissa L.; Baber, Ashleigh E.; Lewis, Emily A.; Michaelides, Angelos; Sykes, E. Charles H.

    2014-07-01

    Methanol is a versatile chemical feedstock, fuel source, and energy storage material. Many reactions involving methanol are catalyzed by transition metal surfaces, on which hydrogen-bonded methanol overlayers form. As with water, the structure of these overlayers is expected to depend on a delicate balance of hydrogen bonding and adsorbate-substrate bonding. In contrast to water, however, relatively little is known about the structures methanol overlayers form and how these vary from one substrate to another. To address this issue, herein we analyze the hydrogen bonded networks that methanol forms as a function of coverage on three catalytically important surfaces, Au(111), Cu(111), and Pt(111), using a combination of scanning tunneling microscopy and density functional theory. We investigate the effect of intermolecular interactions, surface coverage, and adsorption energies on molecular assembly and compare the results to more widely studied water networks on the same surfaces. Two main factors are shown to direct the structure of methanol on the surfaces studied: the surface coverage and the competition between the methanol-methanol and methanol-surface interactions. Additionally, we report a new chiral form of buckled hexamer formed by surface bound methanol that maximizes the interactions between methanol monomers by sacrificing interactions with the surface. These results serve as a direct comparison of interaction strength, assembly, and chirality of methanol networks on Au(111), Cu(111), and Pt(111) which are catalytically relevant for methanol oxidation, steam reforming, and direct methanol fuel cells.

  5. Structure and energetics of hydrogen-bonded networks of methanol on close packed transition metal surfaces.

    PubMed

    Murphy, Colin J; Carrasco, Javier; Lawton, Timothy J; Liriano, Melissa L; Baber, Ashleigh E; Lewis, Emily A; Michaelides, Angelos; Sykes, E Charles H

    2014-07-01

    Methanol is a versatile chemical feedstock, fuel source, and energy storage material. Many reactions involving methanol are catalyzed by transition metal surfaces, on which hydrogen-bonded methanol overlayers form. As with water, the structure of these overlayers is expected to depend on a delicate balance of hydrogen bonding and adsorbate-substrate bonding. In contrast to water, however, relatively little is known about the structures methanol overlayers form and how these vary from one substrate to another. To address this issue, herein we analyze the hydrogen bonded networks that methanol forms as a function of coverage on three catalytically important surfaces, Au(111), Cu(111), and Pt(111), using a combination of scanning tunneling microscopy and density functional theory. We investigate the effect of intermolecular interactions, surface coverage, and adsorption energies on molecular assembly and compare the results to more widely studied water networks on the same surfaces. Two main factors are shown to direct the structure of methanol on the surfaces studied: the surface coverage and the competition between the methanol-methanol and methanol-surface interactions. Additionally, we report a new chiral form of buckled hexamer formed by surface bound methanol that maximizes the interactions between methanol monomers by sacrificing interactions with the surface. These results serve as a direct comparison of interaction strength, assembly, and chirality of methanol networks on Au(111), Cu(111), and Pt(111) which are catalytically relevant for methanol oxidation, steam reforming, and direct methanol fuel cells.

  6. Structure and energetics of hydrogen-bonded networks of methanol on close packed transition metal surfaces.

    PubMed

    Murphy, Colin J; Carrasco, Javier; Lawton, Timothy J; Liriano, Melissa L; Baber, Ashleigh E; Lewis, Emily A; Michaelides, Angelos; Sykes, E Charles H

    2014-07-01

    Methanol is a versatile chemical feedstock, fuel source, and energy storage material. Many reactions involving methanol are catalyzed by transition metal surfaces, on which hydrogen-bonded methanol overlayers form. As with water, the structure of these overlayers is expected to depend on a delicate balance of hydrogen bonding and adsorbate-substrate bonding. In contrast to water, however, relatively little is known about the structures methanol overlayers form and how these vary from one substrate to another. To address this issue, herein we analyze the hydrogen bonded networks that methanol forms as a function of coverage on three catalytically important surfaces, Au(111), Cu(111), and Pt(111), using a combination of scanning tunneling microscopy and density functional theory. We investigate the effect of intermolecular interactions, surface coverage, and adsorption energies on molecular assembly and compare the results to more widely studied water networks on the same surfaces. Two main factors are shown to direct the structure of methanol on the surfaces studied: the surface coverage and the competition between the methanol-methanol and methanol-surface interactions. Additionally, we report a new chiral form of buckled hexamer formed by surface bound methanol that maximizes the interactions between methanol monomers by sacrificing interactions with the surface. These results serve as a direct comparison of interaction strength, assembly, and chirality of methanol networks on Au(111), Cu(111), and Pt(111) which are catalytically relevant for methanol oxidation, steam reforming, and direct methanol fuel cells. PMID:25005297

  7. Design of a novel automated methanol feed system for pilot-scale fermentation of Pichia pastoris.

    PubMed

    Hamaker, Kent H; Johnson, Daniel C; Bellucci, Joseph J; Apgar, Kristie R; Soslow, Sherry; Gercke, John C; Menzo, Darrin J; Ton, Christopher

    2011-01-01

    Large-scale fermentation of Pichia pastoris requires a large volume of methanol feed during the induction phase. However, a large volume of methanol feed is difficult to use in the processing suite because of the inconvenience of constant monitoring, manual manipulation steps, and fire and explosion hazards. To optimize and improve safety of the methanol feed process, a novel automated methanol feed system has been designed and implemented for industrial fermentation of P. pastoris. Details of the design of the methanol feed system are described. The main goals of the design were to automate the methanol feed process and to minimize the hazardous risks associated with storing and handling large quantities of methanol in the processing area. The methanol feed system is composed of two main components: a bulk feed (BF) system and up to three portable process feed (PF) systems. The BF system automatically delivers methanol from a central location to the portable PF system. The PF system provides precise flow control of linear, step, or exponential feed of methanol to the fermenter. Pilot-scale fermentations with linear and exponential methanol feeds were conducted using two Mut(+) (methanol utilization plus) strains, one expressing a recombinant therapeutic protein and the other a monoclonal antibody. Results show that the methanol feed system is accurate, safe, and efficient. The feed rates for both linear and exponential feed methods were within ± 5% of the set points, and the total amount of methanol fed was within 1% of the targeted volume.

  8. Design of a novel automated methanol feed system for pilot-scale fermentation of Pichia pastoris.

    PubMed

    Hamaker, Kent H; Johnson, Daniel C; Bellucci, Joseph J; Apgar, Kristie R; Soslow, Sherry; Gercke, John C; Menzo, Darrin J; Ton, Christopher

    2011-01-01

    Large-scale fermentation of Pichia pastoris requires a large volume of methanol feed during the induction phase. However, a large volume of methanol feed is difficult to use in the processing suite because of the inconvenience of constant monitoring, manual manipulation steps, and fire and explosion hazards. To optimize and improve safety of the methanol feed process, a novel automated methanol feed system has been designed and implemented for industrial fermentation of P. pastoris. Details of the design of the methanol feed system are described. The main goals of the design were to automate the methanol feed process and to minimize the hazardous risks associated with storing and handling large quantities of methanol in the processing area. The methanol feed system is composed of two main components: a bulk feed (BF) system and up to three portable process feed (PF) systems. The BF system automatically delivers methanol from a central location to the portable PF system. The PF system provides precise flow control of linear, step, or exponential feed of methanol to the fermenter. Pilot-scale fermentations with linear and exponential methanol feeds were conducted using two Mut(+) (methanol utilization plus) strains, one expressing a recombinant therapeutic protein and the other a monoclonal antibody. Results show that the methanol feed system is accurate, safe, and efficient. The feed rates for both linear and exponential feed methods were within ± 5% of the set points, and the total amount of methanol fed was within 1% of the targeted volume. PMID:21485036

  9. Electrochemical conversion of carbon dioxide to methanol with the assistance of formate dehydrogenase and methanol dehydrogenase as biocatalysts

    SciTech Connect

    Kuwabata, Susumu; Tsuda, Ryo; Yoneyama, Hiroshi )

    1994-06-15

    Electrolysis at potentials between -0.7 and -0.9 V vs SCE of carbon dioxide-saturated phosphate buffer solutions (pH7) containing formate dehydrogenase (FDH) and either methyl viologen (MV[sup 2+]) or pyrroloquinolinequinone (PQQ) as an electron mediator yielded formate with current efficiencies as high as 90%. The enzyme was durable as long as the electrolysis was carried out in the dark. Electrolysis of phosphate buffer solutions containing sodium formate in the presence of methanol dehydrogenase (MDH) and MV[sup 2+] at -0.7 V vs SCE yielded formaldehyde if the concentration of the enzyme used was low, whereas both formaldehyde and methanol were produced for relatively high concentrations of the enzyme where the methanol production began to occur when the formaldehyde produced accumulated. The use of PQQ in place of MV[sup 2+] as the electron mediator exclusively produced methanol alone after some induction period in the electrolysis. On the basis of these results, successful attempts have been made to reduce carbon dioxide to methanol with cooperative assistance of FDH and MDH in the presence of PQQ as the electron mediator. The role of enzyme and mediator in these reduction processes is discussed in detail. 34 refs., 10 figs., 2 tabs.

  10. Partial oxidative conversion of methane to methanol through selective inhibition of methanol dehydrogenase in methanotrophic consortium from landfill cover soil.

    PubMed

    Han, Ji-Sun; Ahn, Chang-Min; Mahanty, Biswanath; Kim, Chang-Gyun

    2013-11-01

    Using a methanotrophic consortium (that includes Methylosinus sporium NCIMB 11126, Methylosinus trichosporium OB3b, and Methylococcus capsulatus Bath) isolated from a landfill site, the potential for partial oxidation of methane into methanol through selective inhibition of methanol dehydrogenase (MDH) over soluble methane monooxygenase (sMMO) with some selected MDH inhibitors at varied concentration range, was evaluated in batch serum bottle and bioreactor experiments. Our result suggests that MDH activity could effectively be inhibited either at 40 mM of phosphate, 100 mM of NaCl, 40 mM of NH4Cl or 50 μM of EDTA with conversion ratios (moles of CH3OH produced per mole CH4 consumed) of 58, 80, 80, and 43 %, respectively. The difference between extent of inhibition in MDH activity and sMMO activity was significantly correlated (n = 6, p < 0.05) with resultant methane to methanol conversion ratio. In bioreactor study with 100 mM of NaCl, a maximum specific methanol production rate of 9 μmol/mg h was detected. A further insight with qPCR analysis of MDH and sMMO coding genes revealed that the gene copy number continued to increase along with biomass during reactor operation irrespective of presence or absence of inhibitor, and differential inhibition among two enzymes was rather the key for methanol production.

  11. Corrosion behaviour of austenitic stainless steel as a function of methanol concentration for direct methanol fuel cell bipolar plate

    NASA Astrophysics Data System (ADS)

    Wang, Lixia; Kang, Bin; Gao, Na; Du, Xiao; Jia, Linan; Sun, Juncai

    2014-05-01

    The corrosion behaviour of an AISI 304 stainless steel (304 SS) is investigated in aqueous acid methanol solutions (0.5 M H2SO4 + 2 ppm HF + x M CH3OH, x = 0, 1, 5, 10 and 20) at 50 °C to simulate the varied anodic operating conditions of direct methanol fuel cells. Electrochemical measurements including potentiodynamic polarisation, potentiostatic polarisation and electrochemical impedance spectroscopy tests, are employed to analyse the corrosion behaviour. The results reveal that the corrosion resistance of 304 SS is enhanced in solutions with higher methanol content. Scanning electron microscopy and inductively coupled plasma atomic emission spectrometry data indicate that the surface corrosion on 304 SS is alleviated when the methanol concentration is increased. According to the X-ray photoelectron spectroscopy and Mott-Schottky analyses, the passive films formed on the 304 SS after potentiostatic tests in all the test solutions are composed of a duplex electronic structure with an external n-type semiconductor layer and an internal p-type semiconductor layer. Further analyses of the surface conductivity conducted by measuring the interfacial contact resistance between the 304 SS and carbon paper reveal that the passive film formed in the solution with higher methanol content exhibits lower conductivity.

  12. Reactivity Descriptors for Direct Methanol Fuel Cell Anode Catalysts

    SciTech Connect

    Ferrin, Peter; Nilekar, Anand U.; Greeley, Jeffrey P.; Mavrikakis, Manos; Rossmeisl, Jan

    2008-11-01

    We have investigated the anode reaction in direct methanol fuel cells using a database of adsorption free energies for 16 intermediates on 12 close-packed transition metal surfaces calculated with periodic, selfconsistent, density functional theory (DFT–GGA). This database, combined with a simple electrokinetic model of the methanol electrooxidation reaction, yields mechanistic insights that are consistent with previous experimental and theoretical studies on Pt, and extends these insights to a broad spectrum of other transition metals. In addition, by using linear scaling relations between the adsorption free energies of various intermediates in the reaction network, we find that the results determined with the full database of adsorption energies can be estimated by knowing only two key descriptors for each metal surface: the free energies of OH and CO on the surface. Two mechanisms for methanol oxidation to CO₂ are investigated: an indirect mechanism that goes through a CO intermediate and a direct mechanism where methanol is oxidized to CO₂ without the formation of a CO intermediate. For the direct mechanism, we find that, because of CO poisoning, only a small current will result on all non-group 11 transition metals; of these metals, Pt is predicted to be the most active. For methanol decomposition via the indirect mechanism, we find that the onset potential is limited either by the ability to activate methanol, by the ability to activate water, or by surface poisoning by CO* or OH*/O*. Among pure metals, there is no obvious candidate for a good anode catalyst, and in order to design a better catalyst, one has to look for bi-functional surfaces such as the well-studied PtRu alloy.

  13. Structures of protonated methanol clusters and temperature effects.

    PubMed

    Fifen, Jean Jules; Nsangou, Mama; Dhaouadi, Zoubeida; Motapon, Ousmanou; Jaidane, Nejm-Eddine

    2013-05-14

    The accurate evaluation of pKa's, or solvation energies of the proton in methanol at a given temperature is subject to the determination of the most favored structures of various isomers of protonated (H(+)(MeOH)n) and neutral ((MeOH)n) methanol clusters in the gas phase and in methanol at that temperature. Solvation energies of the proton in a given medium, at a given temperature may help in the determination of proton affinities and proton dissociation energies related to the deprotonation process in that medium and at that temperature. pKa's are related to numerous properties of drugs. In this work, we were interested in the determination of the most favored structures of various isomers of protonated methanol clusters in the gas phase and in methanol, at a given temperature. For this aim, the M062X/6-31++G(d,p) and B3LYP/6-31++G(d,p) levels of theory were used to perform geometries optimizations and frequency calculations on various isomers of (H(+)(MeOH)n) in both phases. Thermal effects were retrieved using our homemade FORTRAN code. Thus, we accessed the relative populations of various isomers of protonated methanol clusters, in both phases for temperatures ranging from 0 to 400 K. As results, in the gas phase, linear structures are entropically more favorable at high temperatures, while more compact ones are energetically more favorable at lower temperatures. The trend is somewhat different when bulk effects are taken into account. At high temperatures, the linear structure only dominates the population for n ≤ 6, while it is dominated by the cyclic structure for larger cluster sizes. At lower temperatures, compact structures still dominate the population, but with an order different from the one established in the gas phase. Hence, temperature effects dominate solvent effects in small cluster sizes (n ≤ 6), while the reverse trend is noted for larger cluster sizes. PMID:23676038

  14. Methanex cuts its methanol costs with Fletcher purchase

    SciTech Connect

    Plishner, E.S.

    1993-02-17

    Methanex (Vancouver, BC) will significantly reduce' its unit cost of methanol production with the acquisition of all of Fletcher Challenge's (Auckland, NZ) methanol assets. These include the 800,000-m.t./year Cape Horn plant in Chile, one of the world's largest single train facilities. That plant is by far' the lowest-cost supplier of delivered methanol to the U.S., says analyst Sam Kanes of Scotia McLeod (Toronto), with gas costs below $1/1,000 cu.ft. Also included in the deal are two New Zealand plants: Petralgas, with capacity for 520,000 m.t./year, and Synfuel. Synfuel has the capacity to produce the equivalent of 1.8 million m.t./year of chemical-grade methanol, or 70,000 m.t./year of gasoline, or a combination. Currently rated at 450,000 m.t./year of methanol, that could double in 1994 with the addition of distillation capacity. After the transaction, Methanex will have a total of 2.4 million m.t./year of methanol capacity, plus marketing agreements for 1.0 million m.t./year. The company has plans to add 1.2 million m.t. of production (in Trinidad and the U.S.) and 0.6 million m.t. of further marketing arrangements over the next year and a half, bringing the total to over 5.0 million m.t./year. Methanex could have about twice as much capacity as the Saudis,' according to one consultant.

  15. Vanadium oxide decorated carbon nanotubes as a promising support of Pt nanoparticles for methanol electro-oxidation reaction.

    PubMed

    Nouralishahi, Amideddin; Khodadadi, Abbas Ali; Rashidi, Ali Morad; Mortazavi, Yadollah

    2013-03-01

    VO(x)-MWCNTs nanocomposite was prepared via deposition-precipitation method followed by microwave treatment. Platinum nanoparticles were dispersed via polyol process over the nanocomposite support, and thus, prepared electro-catalyst was employed in methanol electro-oxidation reaction. The electro-catalysts were characterized by means of TGA, XRD, EDS, FESEM, TEM, and H(2)-TPR analysis. The electro-catalytic activity and stability of the electrodes toward methanol oxidation reaction in acidic medium were studied by using cyclic voltammetry (CV), CO-stripping, and electrochemical impedance spectroscopy (EIS) techniques. Compared to the Pt/MWCNTs, the Pt/VO(x)-MWCNTs electro-catalyst not only exhibits high electro-catalytic activity, but also shows very good stability during methanol electro-oxidation reaction. In addition, the presence of VO(x) in the composite support dramatically increases the electrochemical active surface area of platinum nanoparticles. The results of electrochemical impedance spectroscopy reveal that formation kinetics of adsorbed hydroxyl group on surface of the electro-catalysts is improved upon vanadium oxide addition to the support. This phenomenon is very helpful to facilitate oxidative removal of adsorbed CO group through bifunctional mechanism on Pt/VO(x)-MWCNTs.

  16. Injector spray characterization of methanol in reciprocating engines

    SciTech Connect

    Dodge, L.; Naegeli, D.

    1994-06-01

    This report covers a study that addressed cold-starting problems in alcohol-fueled, spark-ignition engines by using fine-spray port-fuel injectors to inject fuel directly into the cylinder. This task included development and characterization of some very fine-spray, port-fuel injectors for a methanol-fueled spark-ignition engine. After determining the spray characteristics, a computational study was performed to estimate the evaporation rate of the methanol fuel spray under cold-starting and steady-state conditions.

  17. Process assessment of small scale low temperature methanol synthesis

    SciTech Connect

    Hendriyana; Susanto, Herri Subagjo

    2015-12-29

    Biomass is a renewable energy resource and has the potential to make a significant impact on domestic fuel supplies. Biomass can be converted to fuel like methanol via several step process. The process can be split into following main steps: biomass preparation, gasification, gas cooling and cleaning, gas shift and methanol synthesis. Untill now these configuration still has a problem like high production cost, catalyst deactivation, economy of scale and a huge energy requirements. These problems become the leading inhibition for biomass conversion to methanol, which should be resolved to move towards the economical. To address these issues, we developed various process and new configurations for methanol synthesis via methyl formate. This configuration combining two reactors: the one reactor for the carbonylation of methanol and CO to form methyl formate, and the second for the hydrogenolysis of methyl formate and H{sub 2} to form two molecule of methanol. Four plant process configurations were compared with the biomass basis is 300 ton/day. The first configuration (A) is equipped with a steam reforming process for converting methane to CO and H{sub 2} for increasing H{sub 2}/CO ratio. CO{sub 2} removal is necessary to avoid poisoning the catalyst. COSORB process used for the purpose of increasing the partial pressure of CO in the feed gas. The steam reforming process in B configuration is not used with the aim of reducing the number of process equipment, so expect lower investment costs. For C configuration, the steam reforming process and COSORB are not used with the aim of reducing the number of process equipment, so expect lower investment costs. D configuration is almost similar to the configuration A. This configuration difference is in the synthesis of methanol which was held in a single reactor. Carbonylation and hydrogenolysis reactions carried out in the same reactor one. These processes were analyzed in term of technical process, material and energy

  18. Process assessment of small scale low temperature methanol synthesis

    NASA Astrophysics Data System (ADS)

    Hendriyana, Susanto, Herri; Subagjo

    2015-12-01

    Biomass is a renewable energy resource and has the potential to make a significant impact on domestic fuel supplies. Biomass can be converted to fuel like methanol via several step process. The process can be split into following main steps: biomass preparation, gasification, gas cooling and cleaning, gas shift and methanol synthesis. Untill now these configuration still has a problem like high production cost, catalyst deactivation, economy of scale and a huge energy requirements. These problems become the leading inhibition for biomass conversion to methanol, which should be resolved to move towards the economical. To address these issues, we developed various process and new configurations for methanol synthesis via methyl formate. This configuration combining two reactors: the one reactor for the carbonylation of methanol and CO to form methyl formate, and the second for the hydrogenolysis of methyl formate and H2 to form two molecule of methanol. Four plant process configurations were compared with the biomass basis is 300 ton/day. The first configuration (A) is equipped with a steam reforming process for converting methane to CO and H2 for increasing H2/CO ratio. CO2 removal is necessary to avoid poisoning the catalyst. COSORB process used for the purpose of increasing the partial pressure of CO in the feed gas. The steam reforming process in B configuration is not used with the aim of reducing the number of process equipment, so expect lower investment costs. For C configuration, the steam reforming process and COSORB are not used with the aim of reducing the number of process equipment, so expect lower investment costs. D configuration is almost similar to the configuration A. This configuration difference is in the synthesis of methanol which was held in a single reactor. Carbonylation and hydrogenolysis reactions carried out in the same reactor one. These processes were analyzed in term of technical process, material and energy balance and economic

  19. The combined oxidation of methanol and ethanol on silver catalysts

    SciTech Connect

    Kurina, L.N.; Gryaznov, V.M.; Gul yanova, S.G.; Plakidkin, A.A.; Vedernikov, V.I.

    1985-10-01

    The authors study the oxidation of methanol, ethanol, and mixtures of these alcohols on industrial silver-pumice and silver membrane catalysts as well as the adsorption of these alcohols on silver. The oxidation of the alcohol mixture on the industrial silver-pumice catalyst gives higher yields of both formaldehyde and acetaldehyde than in the oxidation of the alcohols taken individually. It is also shown that an increase in the rates of formaldehyde formation in the combined oxidation of methanol and ethanol was observed on the silver membrane catalyst.

  20. Environmental information volume: Liquid Phase Methanol (LPMEOH{trademark}) project

    SciTech Connect

    1996-05-01

    The purpose of this project is to demonstrate the commercial viability of the Liquid Phase Methanol Process using coal-derived synthesis gas, a mixture of hydrogen and carbon monoxide. This report describes the proposed actions, alternative to the proposed action, the existing environment at the coal gasification plant at Kingsport, Tennessee, environmental impacts, regulatory requirements, offsite fuel testing, and DME addition to methanol production. Appendices include the air permit application, solid waste permits, water permit, existing air permits, agency correspondence, and Eastman and Air Products literature.

  1. Single-cell protein from methanol with Enterobacter aerogenes

    SciTech Connect

    Gnan, S.O.; Abodreheba, A.O.

    1987-02-20

    An identified Enterobacter aerogenes utilizing methanol as a sole carbon source was studied for the optimization of biomass production and the reduction of its nucleic acid content. Results indicated that the highest yield and conversion were obtained at 0.5% methanol. The addition of seawater as a source of trace elements has an adverse effect. However, the addition of urea as source of nitrogen enhanced the growth of E. aerogenes. Heat shock at 60 degrees C for one minute followed by incubation at 50 degrees C for 2 hours caused 72.6% reduction in the nucleic acid. 12 references.

  2. Discovery of methanol electro-oxidation catalysts by combinatorial analysis

    SciTech Connect

    Mallouk, T.E.; Reddington, E.; Pu, C.

    1996-12-31

    Hydrogen fuel cells are likely to become a major energy source in the next century, but they are not ideal for all applications. A safe alternative fuel with a high energy density will be necessary for transportation and mobile applications. Direct methanol-air fuel cells (DMFCs) are an attractive alternative to hydrogen fuel cells because of the high energy density and low cost of methanol as a fuel. However, in order for DMFCs to become commercially viable, better electrocatalysts for the anode reaction need to be developed. This paper describes a combinatorial technique for generating an array of electrodes with varying metal compositions.

  3. Adsorption and Deactivation Characteristics of Cu/ZnO-Based Catalysts for Methanol Synthesis from Carbon Dioxide

    SciTech Connect

    Natesakhawat, Sittichai; Ohodnicki, Paul R; Howard, Bret H; Lekse, Jonathan W; Baltrus, John P; Matranga, Christopher

    2013-07-09

    The adsorption and deactivation characteristics of coprecipitated Cu/ZnO-based catalysts were examined and correlated to their performance in methanol synthesis from CO₂ hydrogenation. The addition of Ga₂O₃ and Y₂O₃ promoters is shown to increase the Cu surface area and CO₂/H₂ adsorption capacities of the catalysts and enhance methanol synthesis activity. Infrared studies showed that CO₂ adsorbs spontaneously on these catalysts at room temperature as both monoand bi-dentate carbonate species. These weakly bound species desorb completely from the catalyst surface by 200 °C while other carbonate species persist up to 500 °C. Characterization using N₂O decomposition, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM) with energy-dispersive X-ray spectroscopy (EDX) analysis clearly indicated that Cu sintering is the main cause of catalyst deactivation. Ga and Y promotion improves the catalyst stability by suppressing the agglomeration of Cu and ZnO particles under pretreatment and reaction conditions.

  4. Pressure and temperature dependence of excess enthalpies of methanol + tetraethylene glycol dimethyl ether and methanol + polyethylene glycol dimethyl ether 250

    SciTech Connect

    Lopez, E.R.; Coxam, J.Y.; Fernandez, J.; Grolier, J.P.E.

    1999-12-01

    The excess molar enthalpies at 323.15 K, 373.15 K, and 423.15 K, at 8 MPa, are reported for the binary mixtures methanol + tetraethylene glycol dimethyl ether (TEGDME) and methanol + poly(ethylene glycol) dimethyl ether 250 (PEGDME 250). Excess molar enthalpies were determined with a Setaram C-80 calorimeter equipped with a flow mixing cell. For both systems, the excess enthalpies are positive over the whole composition range, increasing with temperature. The H{sup E}(x) curves are slightly asymmetrical, and their maxima are skewed toward the methanol-rich region. The excess enthalpies slightly change with the pressure, the sign of this change being composition-dependent. In the case of mixtures with TEGDME, the experimental H{sup E} values have been compared with those predicted with the Gmehling et al. version of UNIFAC (Dortmund) and the Nitta-Chao and DISQUAC group contribution models.

  5. Preparation of Carbon-Platinum-Ceria and Carbon-Platinum-Cerium catalysts and its application in Polymer Electrolyte Fuel Cell: Hydrogen, Methanol, and Ethanol

    NASA Astrophysics Data System (ADS)

    Guzman Blas, Rolando Pedro

    This thesis is focused on fuel cells using hydrogen, methanol and ethanol as fuel. Also, in the method of preparation of catalytic material for the anode: Supercritical Fluid Deposition (SFD) and impregnation method using ethylenediaminetetraacetic acid (EDTA) as a chelating agent. The first part of the thesis describes the general knowledge about Hydrogen Polymer Exchange Membrane Fuel Cell (HPEMFC),Direct Methanol Fuel Cell (DMFC) and Direct Ethanol Fuel Cell (DEFC), as well as the properties of Cerium and CeO2 (Ceria). The second part of the thesis describes the preparation of catalytic material by Supercritical Fluid Deposition (SFD). SFD was utilized to deposit Pt and ceria simultaneously onto gas diffusion layers. The Pt-ceria catalyst deposited by SFD exhibited higher methanol oxidation activity compared to the platinum catalyst alone. The linear sweep traces of the cathode made for the methanol cross over study indicate that Pt-Ceria/C as the anode catalyst, due to its better activity for methanol, improves the fuel utilization, minimizing the methanol permeation from anode to cathode compartment. The third and fourth parts of the thesis describe the preparation of material catalytic material Carbon-Platinum-Cerium by a simple and cheap impregnation method using EDTA as a chelating agent to form a complex with cerium (III). This preparation method allows the mass production of the material catalysts without additional significant cost. Fuel cell polarization and power curves experiments showed that the Carbon-Platinum-Cerium anode materials exhibited better catalytic activity than the only Vulcan-Pt catalysts for DMFC, DEFC and HPEMFC. In the case of Vulcan-20%Pt-5%w Cerium, this material exhibits better catalytic activity than the Vulcan-20%Pt in DMFC. In the case of Vulcan-40% Pt-doped Cerium, this material exhibits better catalytic activity than the Vulcan-40% Pt in DMFC, DEFC and HPEMFC. Finally, I propose a theory that explains the reason why the

  6. Conservative management of spontaneous abortions. Women's experiences.

    PubMed Central

    Wiebe, E.; Janssen, P.

    1999-01-01

    OBJECTIVE: To describe women's experiences with expectant management of spontaneous abortions. DESIGN: Descriptive survey using questionnaires with fixed-choice and open-ended questions. The latter were analyzed for themes, using qualitative methods. SETTING: Urban and suburban private primary care family practices. PARTICIPANTS: A convenience sample of family practice patients (59 of 80 eligible) pregnant for less than 12 weeks who had spontaneous abortions without surgery. Response rate was 84.7%; 50 questionnaires were received from the 59 women. METHOD: Women were asked about their physical experiences, including amount of pain and bleeding; emotional effects; their satisfaction with medical care; and their suggestions for improving care. MAIN FINDINGS: The mean worst pain experienced during a spontaneous abortion on an 11-point scale was 5.9. Bleeding varied, but was often very heavy. Satisfaction rate was 92.9% with family physician care and 84.6% with hospital care. Women described the emotional effect of "natural" spontaneous abortions and made recommendations for improving care. CONCLUSIONS: A better understanding of the physical and emotional experiences of the women in this study might help physicians better prepare and support patients coping with expectant management of spontaneous abortions. PMID:10540695

  7. Hyperprolactinemia due to spontaneous intracranial hypotension.

    PubMed

    Schievink, Wouter I; Nuño, Miriam; Rozen, Todd D; Maya, M Marcel; Mamelak, Adam N; Carmichael, John; Bonert, Vivien S

    2015-05-01

    OBJECT Spontaneous intracranial hypotension is an increasingly recognized cause of headaches. Pituitary enlargement and brain sagging are common findings on MRI in patients with this disorder. The authors therefore investigated pituitary function in patients with spontaneous intracranial hypotension. METHODS Pituitary hormones were measured in a group of 42 consecutive patients with spontaneous intracranial hypotension. For patients with hyperprolactinemia, prolactin levels also were measured following treatment. Magnetic resonance imaging was performed prior to and following treatment. RESULTS The study group consisted of 27 women and 15 men with a mean age at onset of symptoms of 52.2 ± 10.7 years (mean ± SD; range 17-72 years). Hyperprolactinemia was detected in 10 patients (24%), ranging from 16 ng/ml to 96.6 ng/ml in men (normal range 3-14.7 ng/ml) and from 31.3 ng/ml to 102.5 ng/ml in women (normal range 3.8-23.2 ng/ml). In a multivariate analysis, only brain sagging on MRI was associated with hyperprolactinemia. Brain sagging was present in 60% of patients with hyperprolactinemia and in 19% of patients with normal prolactin levels (p = 0.02). Following successful treatment of the spontaneous intracranial hypotension, hyperprolactinemia resolved, along with normalization of brain MRI findings in all 10 patients. CONCLUSIONS Spontaneous intracranial hypotension is a previously undescribed cause of hyperprolactinemia. Brain sagging causing distortion of the pituitary stalk (stalk effect) may be responsible for the hyperprolactinemia. PMID:25380110

  8. Prevalence of spontaneous dyskinesia in schizophrenia.

    PubMed

    Fenton, W S

    2000-01-01

    Spontaneous abnormal involuntary movements phenomenologically identical to neuroleptic-induced tardive dyskinesia have been described in schizophrenia for over a century. Because at present nearly all patients with schizophrenia are exposed to neuroleptic medications, information about the prevalence of spontaneous dyskinesia is obtained from accounts from the preneuroleptic era, evaluations of first-episode patients before neuroleptic treatment, and the identification and assessment of drug-naive patients in developing countries. In this report, data from 14 studies of neuroleptic-naive patients with schizophrenia are used to generate age-adjusted estimates of the prevalence of spontaneous dyskinesia. While the precision of this estimate is limited by the difficulty of obtaining large, untreated samples, available data suggest a spontaneous dyskinesia rate of approximately 4% in first-episode schizophrenic patients, 12% for patients ill several years but below age 30 years, 25% for those aged between 30 and 50 years, and 40% for those aged 60 years or older. Relative to the incidence and accrued prevalence of spontaneous dyskinesia expected during the natural history of untreated schizophrenia, the cumulative impact of treatment with new neuroleptic agents has yet to be determined.

  9. Spontaneous configuring in conditioned flavor aversion.

    PubMed

    Forbes, D T; Holland, P C

    1985-04-01

    A series of experiments investigated spontaneous configuring using the conditioned flavor aversion paradigm with rat subjects. In Experiment 1, extended training of a two-flavor compound stimulus did not produce spontaneous differentiation of conditioned responding to that compound and its elements. In Experiment 2 we found that extended nonreinforced exposure to a compound stimulus generated spontaneous element-compound differentiation when the elements were later conditioned. Rats that received extended preexposure to the compound showed less conditioned responding to the compound than to either of its elements. However, rats that had not received preexposure to the compound showed greater conditioned responding to the compound than to either of its elements (summation). In Experiment 3, nonreinforced preexposure to the compound stimulus prior to minimal reinforced compound training produced spontaneous compound-element differentiation, but extended reinforced compound training eliminated that differentiation. In Experiment 4, extended partial reinforcement training with a compound produced differentiation of the compound from its elements. Implications of these data for the mechanisms responsible for spontaneous configuring and for the summation assumptions common to most learning theories are discussed.

  10. Spontaneous intrathyroidal hematoma causing airway obstruction

    PubMed Central

    Best, Corliss A.E.; Dhaliwal, Sandeep; Tam, Samantha; Low, T. Hubert; Hughes, Brian; Fung, Kevin; MacNeil, S. Danielle

    2016-01-01

    Abstract Introduction: Spontaneous thyroid hemorrhage is a rare occurrence that results in pain, discomfort, and occasionally compressive symptoms. Infrequently, extensive thyroid hemorrhage can result in a rapidly expanding hematoma resulting in airway compromise. This is a case of an otherwise healthy young woman, 3 months postpartum, with a slowly expanding spontaneous thyroid hemorrhage that measured at 7 × 5.5 × 5 cm by computed tomography. She ultimately required intubation to manage respiratory distress and subsequently a hemithyroidectomy for definitive treatment. The case presentation is followed by a literature review where known etiologies of thyroid hematoma including traumatic and nontraumatic causes, precipitating anticoagulation, and spontaneous rupture of branches of the external carotid artery are outlined. The potential links to pregnancy are explored. The roles of bedside thyroid ultrasound in the emergency department and lateral neck roentgenogram in diagnosis are explored. The importance of airway management and indications for conservative versus surgical treatments are discussed. Conclusions: This is a case of a spontaneous intrathyroidal hemorrhage, which progressed over days to ultimately cause airway compromise. It is imperative that physicians are educated on the appropriate detection and management of the potentially life-threatening spontaneous thyroid hematoma. PMID:27583841

  11. PtRu nanofilm formation by electrochemical atomic layer deposition (E-ALD).

    PubMed

    Jayaraju, Nagarajan; Banga, Dhego; Thambidurai, Chandru; Liang, Xuehai; Kim, Youn-Guen; Stickney, John L

    2014-03-25

    The high CO tolerance of PtRu electrocatalysis, compared with pure Pt and other Pt-based alloys, makes it interesting as an anode material in proton exchange membrane fuel cells (PEMFC) and direct methanol fuel cells (DMFC). This report describes the formation of bimetallic PtRu nanofilms using the electrochemical form of atomic layer deposition (E-ALD). Metal nanofilm formation using E-ALD is facilitated by use of surface-limited redox replacement (SLRR), where an atomic layer (AL) of a sacrificial metal is first formed by UPD. The AL is then spontaneously exchanged for a more noble metal at the open-circuit potential (OCP). In the present study, PtRu nanofilms were formed using SLRR for Pt and Ru, and Pb UPD was used to form the sacrificial layers. The PtRu E-ALD cycle consisted of Pb UPD at -0.19 V, followed by replacement using Pt(IV) ions at OCP, rinsing with blank, then Pb UPD at -0.19 V, followed by replacement using Ru(III) ions at OCP. PtRu nanofilm thickness was controlled by the number of times the cycle was repeated. PtRu nanofilms with atomic proportions of 70/30, 82/18, and 50/50 Pt/Ru were formed on Au on glass slides using related E-ALD cycles. The charge for Pb UPD and changes in the OCP during replacement were monitored during the deposition process. The PtRu films were then characterized by CO adsorption and electrooxidation to determine their overpotentials. The 50/50 PtRu nanofilms displayed the lowest CO electrooxidation overpotentials as well as the highest currents, compared with the other alloy compositions, pure Pt, and pure Ru. In addition, CO electrooxidation studies of the terminating AL on the 50/50 PtRu nanostructured alloy were investigated by deposition of one or two SLRR of Pt, Ru, or PtRu on top.

  12. ZnS/Zn(O,OH)S-based buffer layer deposition for solar cells

    DOEpatents

    Bhattacharya, Raghu N.

    2009-11-03

    The invention provides CBD ZnS/Zn(O,OH)S and spray deposited ZnS/Zn(O,OH)S buffer layers prepared from a solution of zinc salt, thiourea and ammonium hydroxide dissolved in a non-aqueous/aqueous solvent mixture or in 100% non-aqueous solvent. Non-aqueous solvents useful in the invention include methanol, isopropanol and triethyl-amine. One-step deposition procedures are described for CIS, CIGS and other solar cell devices.

  13. Highly elevated emission of mercury vapor due to the spontaneous combustion of refuse in a landfill

    NASA Astrophysics Data System (ADS)

    Zhu, Wei; Sommar, Jonas; Li, Zhonggen; Feng, Xinbin; Lin, Che-Jen; Li, Guanghui

    2013-11-01

    Refuse disposal (e.g., landfilling and incineration) have been recognized as a significant anthropogenic source of mercury (Hg) emission globally. However, in-situ measurements of Hg emission from landfill or refuse dumping sites where fugitive spontaneous combustion occurs have not been reported. Gaseous elemental mercury (Hg0) concentration and emission flux were observed near spontaneous combustions of refuse at a landfill site in southwestern China. Ambient Hg0 concentrations above the refuse surface ranged from 42.7 ± 20.0 to 396.4 ± 114.2 ng m-3, up to 10 times enhancement due to the spontaneous burning. Using a box model with Hg0 data obtained from 2004 to 2013, we estimated that the Hg0 emission from refuse was amplified by 8-40 times due to spontaneous combustion. A micrometeorological flux measurement system based on relaxed eddy accumulation was configured downwind of the combustion sites to quantify the Hg0 emission. Extremely large turbulent deposition fluxes (up to -128.6 μg m-2 h-1, 20 min average) were detected during periods of high Hg0 concentration events over the measurement footprint. The effect of temperature, moisture and light on the air-surface exchange of Hg0 exchange was found to be masked by the overwhelming deposition of Hg0 from the enriched air from the refuse combustion plumes. This research reveals that mercury emission from the landfill refuse can be boosted by fugitive spontaneous combustion of refuse. The emission represents an anthropogenic source that has been overlooked in Hg inventory estimates.

  14. Environmental controls over methanol production, emission, and δ13C values from Lycopersicon esculentum

    NASA Astrophysics Data System (ADS)

    Oikawa, P.; Giebel, B. M.; Mak, J. E.; Riemer, D. D.; Swart, P. K.; Lerdau, M.

    2009-12-01

    Phytogenic methanol is the dominant source of methanol to the atmosphere, where it is the second most abundant organic compound. Beyond methanol’s role in atmospheric chemistry, it is an indicator of plant function and is linked to plant wound response. Methanol emissions are considered to be a by-product of cell wall expansion and, more specifically, the demethylation of pectin by pectin methylesterase (PME) in cell walls. Production of methanol was investigated in mature and immature tomato Lycopersicon esculentum via measurement of methanol flux, foliar PME activity, and methanol extraction from leaf, root, and stem tissues. δ13C values for mature and immature methanol emissions were also measured using a GC-IRMS system. Environmental control over methanol production and emission was studied by changing temperature and light while holding stomatal conductance constant. As seen previously, mature leaf methanol emissions were significantly less than immature emissions. Surprisingly, preliminary results suggest mature leaf methanol production to be similar to immature leaves, indicating an enhanced metabolic sink for methanol in mature leaves. These data enhance our understanding of methanol production, a term which is not well constrained in current methanol flux models.

  15. Pulsed laser deposition of anatase thin films on textile substrates

    NASA Astrophysics Data System (ADS)

    Krämer, André; Kunz, Clemens; Gräf, Stephan; Müller, Frank A.

    2015-10-01

    Pulsed laser deposition (PLD) is a highly versatile tool to prepare functional thin film coatings. In our study we utilised a Q-switched CO2 laser with a pulse duration τ ≈ 300 ns, a laser wavelength λ = 10.59 μm, a repetition frequency frep = 800 Hz and a peak power Ppeak = 15 kW to deposit crystalline anatase thin films on carbon fibre fabrics. For this purpose, preparatory experiments were performed on silicon substrates to optimise the anatase deposition conditions including the influence of different substrate temperatures and oxygen partial pressures. Processing parameters were then transferred to deposit anatase on carbon fibres. Scanning electron microscopy, X-ray diffraction analyses, Raman spectroscopy and tactile profilometry were used to characterise the samples and to reveal the formation of phase pure anatase without the occurrence of a secondary rutile phase. Methanol conversion test were used to prove the photocatalytic activity of the coated carbon fibres.

  16. Spontaneous perception of numerosity in humans

    PubMed Central

    Cicchini, Guido Marco; Anobile, Giovanni; Burr, David C.

    2016-01-01

    Humans, including infants, and many other species have a capacity for rapid, nonverbal estimation of numerosity. However, the mechanisms for number perception are still not clear; some maintain that the system calculates numerosity via density estimates—similar to those involved in texture—while others maintain that more direct, dedicated mechanisms are involved. Here we show that provided that items are not packed too densely, human subjects are far more sensitive to numerosity than to either density or area. In a two-dimensional space spanning density, area and numerosity, subjects spontaneously react with far greater sensitivity to changes in numerosity, than either area or density. Even in tasks where they were explicitly instructed to make density or area judgments, they responded spontaneously to number. We conclude, that humans extract number information, directly and spontaneously, via dedicated mechanisms. PMID:27555562

  17. Spontaneous closure of congenital coronary artery fistulas

    PubMed Central

    Schleich, J; Rey, C; Gewillig, M; Bozio, A

    2001-01-01

    Six cases of full spontaneous closure of congenital coronary artery fistulas, and one case of near closure, as seen by colour Doppler echocardiography, are presented. It is worth reconsidering the classical view that nearly all cases of spontaneous closure are eligible for surgical or percutaneous correction to prevent the development of significant and potentially fatal complications. As the natural course of coronary artery fistulas is still poorly defined, asymptomatic patients, especially those under 7 years old with small shunts, should be periodically followed up by echocardiography rather than be subjected to operative closure, even by catheterisation.


Keywords: congenital heart disease; coronary artery disease; coronary artery fistula; spontaneous closure PMID:11250983

  18. Spontaneous rupture of the common bile duct.

    PubMed

    Kyzer, S; Bayer, I; Chaimoff, C

    1986-01-01

    Spontaneous rupture of the common bile duct in adults is very rare. The authors report only the 14th case in the Western literature. A 25-year-old woman had signs of peritonitis suggestive of a perforated appendix, but at operation the appendix appeared normal and a large amount of bile was found in the peritoneal cavity. A 2-mm tear was found on the anterior wall of the common bile duct. The patient recovered without complications after T-tube drainage and cholecystectomy. In this patient none of the factors thought to cause spontaneous rupture of the common bile duct were present, so the authors conclude that the case may be classified as idiopathic spontaneous rupture of the common bile duct. PMID:3940592

  19. Ternary Pt-Ru-Ni catalytic layers for methanol electrooxidation prepared by electrodeposition and galvanic replacement

    PubMed Central

    Papaderakis, Athanasios; Pliatsikas, Nikolaos; Prochaska, Chara; Papazisi, Kalliopi M.; Balomenou, Stella P.; Tsiplakides, Dimitrios; Patsalas, Panagiotis; Sotiropoulos, Sotiris

    2014-01-01

    Ternary Pt-Ru-Ni deposits on glassy carbon substrates, Pt-Ru(Ni)/GC, have been formed by initial electrodeposition of Ni layers onto glassy carbon electrodes, followed by their partial exchange for Pt and Ru, upon their immersion into equimolar solutions containing complex ions of the precious metals. The overall morphology and composition of the deposits has been studied by SEM microscopy and EDS spectroscopy. Continuous but nodular films have been confirmed, with a Pt ÷ Ru ÷ Ni % bulk atomic composition ratio of 37 ÷ 12 ÷ 51 (and for binary Pt-Ni control systems of 47 ÷ 53). Fine topographical details as well as film thickness have been directly recorded using AFM microscopy. The composition of the outer layers as well as the interactions of the three metals present have been studied by XPS spectroscopy and a Pt ÷ Ru ÷ Ni % surface atomic composition ratio of 61 ÷ 12 ÷ 27 (and for binary Pt-Ni control systems of 85 ÷ 15) has been found, indicating the enrichment of the outer layers in Pt; a shift of the Pt binding energy peaks to higher values was only observed in the presence of Ru and points to an electronic effect of Ru on Pt. The surface electrochemistry of the thus prepared Pt-Ru(Ni)/GC and Pt(Ni)/GC electrodes in deaerated acid solutions (studied by cyclic voltammetry) proves the existence of a shell consisting exclusively of Pt-Ru or Pt. The activity of the Pt-Ru(Ni) deposits toward methanol oxidation (studied by slow potential sweep voltammetry) is higher from that of the Pt(Ni) deposit and of pure Pt; this enhancement is attributed both to the well-known Ru synergistic effect due to the presence of its oxides but also (based on the XPS findings) to a modification effect of Pt electronic properties. PMID:24959530

  20. Southeast New Mexico. Methanol foam fracs open up Delaware

    SciTech Connect

    Mickey, V.

    1983-10-01

    Part of the recent success in Brushy Canyon, Cherry Canyon, and Delaware formations in SE. New Mexico is being attributed to improved stimulation techniques. Historically, fracturing Delaware-age sands caused water sensitive clays within the formation to swell. Methanol foam fracs have been applied in Delaware-aged formations for the past year, and results are encouraging. Well potentials have been improved on some wells from under 10 bopd after acidization to 100 bopd after stimulation with methanol in nitrogen foam. The wells are cleaned up after perforation with 7.5% iron and clay control acid. Then the well is stimulated with a 75-quality nitrogen foam. The remaining 25% of the fluid is 50% methanol and 50% KCl water, 2% or 3% concentration. Additives required are minor, and typically include 1 gal/1,000/gal of some nonemulsifying agent and a special methanol foamer. The base fluid is a 30-lb gel system which gives stability to the foam and improves the foam's sand transport qualities. The gel also reduces friction pressures.

  1. IRIS Toxicological Review of Methanol (Noncancer) (Interagency Science Discussion Draft)

    EPA Science Inventory

    On May 3, 2013, the Toxicological Review of Methanol (noncancer) (Revised External Review Draft) was posted for public review and comment. Subsequently, the draft Toxicological Review, Appendices, and draft IRIS Summary were reviewed internally by EPA and by other federal agenci...

  2. IRIS Toxicological Review of Methanol (External Review Draft, 2013)

    EPA Science Inventory

    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.

  3. Probing methanol cluster growth by vacuum ultraviolet ionization.

    PubMed

    Bandyopadhyay, Biswajit; Kostko, Oleg; Fang, Yigang; Ahmed, Musahid

    2015-05-01

    The ability to probe the formation and growth of clusters is key to answering fundamental questions in solvation and nucleation phenomena. Here, we present a mass spectrometric study of methanol cluster dynamics to investigate these two major processes. The clusters are produced in a molecular beam and ionized by vacuum ultraviolet (VUV) radiation at intermediate distances between the nozzle and the skimmer sampling different regimes of the supersonic expansion. The resulting cluster distribution is studied by time-of-flight mass spectrometry. Experimental conditions are optimized to produce intermediate size protonated methanol and methanol-water clusters and mass spectra and photoionization onsets and obtained. These results demonstrate that intensity distributions vary significantly at various nozzle to ionization distances. Ion-molecule reactions closer to the nozzle tend to dominate leading to the formation of protonated species. The protonated trimer is found to be the most abundant ion at shorter distances because of a closed solvation shell, a larger photoionization cross section compared to the dimer, and an enhanced neutral tetramer precursor. On the other hand, the protonated dimer becomes the most abundant ion at farther distances because of low neutral density and an enhanced charged protonated monomer-neutral methanol interaction. Thomson's liquid drop model is used to qualitatively explain the observed distributions.

  4. EVALUATION OF A PROCESS TO CONVERT BIOMASS TO METHANOL FUEL

    EPA Science Inventory

    The report gives results of a review of the design of a reactor capable of gasifying approximately 50 lb/hr of biomass for a pilot-scale facility to develop, demonstrate, and evaluate the Hynol Process, a high-temperature, high-pressure method for converting biomass into methanol...

  5. Methanol along the path from envelope to protoplanetary disk

    NASA Astrophysics Data System (ADS)

    Drozdovskaya, Maria; Van Dishoeck, Ewine; Walsh, Catherine; Visser, Ruud; Harsono, Daniel

    Interstellar methanol is considered a parent species of larger, more complex organic molecules. In this work a 2D physicochemical simulation of infalling parcels of matter is performed for a low-mass star-forming system to trace the chemical evolution from cloud to disk. Full continuum radiative transfer and a comprehensive gas-grain chemistry network are included. With this set up, two sets of collapse models are studied. Various disk zones are delineated for both, based upon their methanol budget. Some zones retain prestellar origins upon readsorption, while others are enhanced en route in the envelope. Under the right conditions, even further enrichment can occur in the disk itself. It is the infall paths that determine the zonal divisions for complex organic molecules in the disk, highlighting that the history of the material influences the disk composition. A comparison to cometary abundances is also performed. Critical chemical processes and parameters for the methanol chemistry under different physical conditions are identified. The exact abundance and distribution of methanol is important for the budget of complex organic molecules in the disk, which will be incorporated into forming planetary system objects such as protoplanets and comets.

  6. Testing of a small combustion turbine burning reformed methanol

    SciTech Connect

    Karpuk, M E; Schell, D J

    1984-02-01

    As part of ongoing research into high-efficiency alcohol fuels utilization at the Solar Energy Research Institute, as gas combustion turbine was modified for use with reformed methanol and tested. The reforming process for this application uses waste engine heat to convert methanol and steam in the presence of a catalyst into hydrogen and carbon dioxide. We modified the standard combustor of a Garrett Model GTCP85-397 combustion turbine to burn the hydrogen and carbon dioxide mixture. Heat exchangers to boil and reform a methanol and water mixture were sized, purchased, and connected to the turbine exhaust. Instrumentation was added to monitor turbine temperatures, pressures, and exhaust emissions. Turbine performance and emissions were measured at various loads with a distillate fuel and compared with performance on reformed methanol. Reformed alcohol yields a significant improvement in efficiency because waste heat is reclaimed as chemical energy in the fuel. The larger mass flowrate of fuel to the combustor increases power output, and emissions are substantially reduced. 5 references, 6 figures, 4 tables.

  7. Techniques for sensing methanol concentration in aqueous environments

    NASA Technical Reports Server (NTRS)

    Narayanan, Sekharipuram R. (Inventor); Chun, William (Inventor); Valdez, Thomas I. (Inventor)

    2001-01-01

    An analyte concentration sensor that is capable of fast and reliable sensing of analyte concentration in aqueous environments with high concentrations of the analyte. Preferably, the present invention is a methanol concentration sensor device coupled to a fuel metering control system for use in a liquid direct-feed fuel cell.

  8. METHANOL PRODUCTION FROM BIOMASS AND NATURAL GAS AS TRANSPORTATION FUEL

    EPA Science Inventory

    Two processes are examined for production of methanol. They are assessed against the essential requirements of a future alternative fuel for road transport: that it (i) is producible in amounts comparable to the 19 EJ of motor fuel annually consumed in the U.S., (ii) minimizes em...

  9. IRIS Toxicological Review of Methanol (External Review Draft; December 2009)

    EPA Science Inventory

    NOTE: The IRIS Toxicological Review of Methanol (external review draft; December 2009) was released for public comment and external peer review in January 2010 (Federal Register Not...

  10. Hydrogenolysis of ethylene glycol to methanol over modified RANEY® catalysts.

    PubMed

    Wu, Cheng-Tar; Qu, Jin; Elliott, Joseph; Yu, Kai Man Kerry; Tsang, Shik Chi Edman

    2013-06-21

    There is tremendous growing interest in utilizing biomass molecules for energy provision due to their carbon neutrality. Here, we employ ethylene glycol as a model compound for catalytic activation, which represents a basic unit for complex carbohydrate molecules (polyols). In this paper, hydrogenolysis of ethylene glycol to produce methanol in hydrogen over modified RANEY® Ni and Cu catalysts has been studied. This work provides essential information that may leads to the development of new catalysts for carbohydrate activation to methanol, a novel but important reaction concerning biomass conversion to transportable form of energy. Particularly, in this study, modification of electronic structure hence adsorption properties of RANEY® catalysts has mainly been achieved by blending with second metal(s). It is found that the activity and selectivity of this reaction can be significantly affected by this approach. In contrast, there is no subtle effect on methanol selectivity despite a great variation in the d-band centre position which shows a distinctive effect on other products. This result suggests that methanol is produced on specific surface sites independent from the other sites at an intrinsic rate and will not be converted to other products by the d-band alteration. PMID:23661262

  11. Cononsolvency behavior of hydrophobes in water + methanol mixtures.

    PubMed

    Mochizuki, Kenji; Koga, Kenichiro

    2016-06-28

    The molecular origin of cononsolvency behavior is explored using molecular dynamics simulations. Cononsolvency behavior in aggregations of methane molecules and conformational changes of those clusters dissolved in water + methanol mixtures are confirmed by re-entrant changes in the solvent-mediated interactions with increasing methanol concentration. The results indicate that the cononsolvency behavior arises from the solute-solute hydrophobic interactions rather than other interactions such as solute-solvent hydrophilic interactions. Furthermore, we show that even the van der Waals interaction is not necessary to induce the cononsolvency behavior by investigating the dimerization process of repulsive cavities. The non-monotonic change of the solvent-mediated interaction results from the difference in the concentration dependencies of excess chemical potentials between an isolated methane and methane clusters. The concentration dependencies of the excess chemical potentials are decomposed into contributions from various intermolecular effective interactions through the framework of the Kirkwood-Buff theory, and then we show that the change of the relative magnitude between hydrophobe-methanol and hydrophobe-water effective interactions with increasing methanol concentration is responsible for the cononsolvency behavior. PMID:27251342

  12. Infrared Spectrum of Methanol: A First-Year Student Experiment.

    ERIC Educational Resources Information Center

    Boehm, Garth; Dwyer, Mark

    1981-01-01

    Describes an experiment providing an experimental introduction to vibrational spectroscopy and experience in using an elementary vacuum line. The experiment, using a gas cell charged with methanol, is completed in a three-hour laboratory period and is directed toward understanding vibrational spectroscopy rather than the diagnostic value of the…

  13. On direct and indirect methanol fuel cells for transportation applications

    SciTech Connect

    Gottesfield, S.

    1996-04-01

    Research on direct oxidation methanol fuel cells (DMFCs) and polymer electrolyte fuel cells (PEFCs) is discussed. Systems considered for transportation applications are addressed. The use of platinum/ruthenium anode electrocatalysts and platinum cathode electrocatalysts in polymer electrolyte DMFCs has resulted in significant performance enhancements.

  14. IRIS Toxicological Review of Methanol (Noncancer) (Revised External Review Draft)

    EPA Science Inventory

    EPA is seeking additional public comment and external peer review of the scientific basis supporting the human health hazard and dose-response assessment of methanol (noncancer).

  1. [Spontaneous heterotopic pregnancy and fetal survival].

    PubMed

    Luna Lugo, Gilberto; Rangel Ruiz, Irais; Gutiérrez Laiza, Nadia Saray; Martínez Guerrero, Misael Eleazar; Méndez Oceguera, José Raúl; Suárez López, Norma María Luisa

    2011-08-01

    The spontaneous heterotopic pregnancy is an unusual event. Generally the extrauterine product lost and the intrauterine present complications in different grade. The most common is the rupture and can be associated with hemodynamic unstable with risk for patient's life. The intrauterine pregnancy can be continuing to the end. We report the case of patient with spontaneous heterotopic pregnancy; the diagnosis was in the first trimester, with two products (intrauterine and in right fimbrius). The salpingectomy is doing with the extrauterine pregnancy and the patient has not complications trans or postoperative time and without complications for the intrauterine pregnancy, she continues with stricter control until to obtain a life product.

  2. Spontaneous symmetry breaking in gauge theories.

    PubMed

    Kibble, T W B

    2015-01-13

    The aim of this historical article is to describe the development of the idea of spontaneous symmetry breaking in gauge theories as seen from my perspective as a member of Abdus Salam's group at Imperial College London, UK. Beginning with an account of particle physics in the years after the Second World War, I describe early attempts at constructing a unified theory of weak and electromagnetic interactions, the obstacles encountered and how they were eventually overcome with the mass-generating mechanism incorporating the idea of spontaneous symmetry breaking, one of whose features is the now-famous Higgs boson.

  3. Primer on spontaneous heating and pyrophoricity

    SciTech Connect

    Not Available

    1994-12-01

    This primer was prepared as an information resource for personnel responsible for operation of DOE nuclear facilities. It has sections on combustion principles, spontaneous heating/ignition of hydrocarbons and organics, pyrophoric gases and liquids, pyrophoric nonmetallic solids, pyrophoric metals (including Pu and U), and accident case studies. Although the information in this primer is not all-encompassing, it should provide the reader with a fundamental knowledge level sufficient to recognize most spontaneous combustion hazards and how to prevent ignition and widespread fires. This primer is provided as an information resource only, and is not intended to replace any fire protection or hazardous material training.

  4. Spontaneous knotting of self-trapped waves

    PubMed Central

    Desyatnikov, Anton S.; Buccoliero, Daniel; Dennis, Mark R.; Kivshar, Yuri S.

    2012-01-01

    We describe theory and simulations of a spinning optical soliton whose propagation spontaneously excites knotted and linked optical vortices. The nonlinear phase of the self-trapped light beam breaks the wave front into a sequence of optical vortex loops around the soliton, which, through the soliton's orbital angular momentum and spatial twist, tangle on propagation to form links and knots. We anticipate similar spontaneous knot topology to be a universal feature of waves whose phase front is twisted and nonlinearly modulated, including superfluids and trapped matter waves. PMID:23105969

  5. Spontaneous retroperitoneal hemorrhage from a ruptured hypernephroma.

    PubMed

    Trivedi, R; Levy, M; Ibrahim, I; Bonacarti, A

    1979-01-01

    The clinical presentation and roentgenographic findings of renal cell carcinoma have been consistently variable. These patients can appear with flank pain mimicking ureteral colic, flank tumors, or symptomatic metastasis [1]. Systemic cardiac manifestations including cardiomegaly with congestive heart failure due to arteriovenous fistula formation have been reported [2] Roentgenographic findings may show the tumor to be either vascular or avascular. It may present as a spontaneous perforation of the pelvic ureteral system which is demonstrated by intravenous pyelography (3). In this article, we describe a case of hypernephroma in a cyst wall causing severe spontaneous hemorrhage in the retroperitoneal space resulting in a state of hypovolemic shock.

  6. Spontaneous hypnotic age regression: case report.

    PubMed

    Spiegel, D; Rosenfeld, A

    1984-12-01

    Age regression--reliving the past as though it were occurring in the present, with age appropriate vocabulary, mental content, and affect--can occur with instruction in highly hypnotizable individuals, but has rarely been reported to occur spontaneously, especially as a primary symptom. The psychiatric presentation and treatment of a 16-year-old girl with spontaneous age regressions accessible and controllable with hypnosis and psychotherapy are described. Areas of overlap and divergence between this patient's symptoms and those found in patients with hysterical fugue and multiple personality syndrome are also discussed.

  7. Optimum ionic conductivity and diffusion coefficient of ion-exchange membranes at high methanol feed concentrations in a direct methanol fuel cell

    NASA Astrophysics Data System (ADS)

    Lee, K.; Nam, J.-D.

    In direct methanol fuel cells (DMFCs), the optimum characteristics of ion-exchange membranes are investigated at high concentrations of methanol feed up to 7 M by modifying the diffusion coefficient and the ionic conductivity of the polyelectrolyte material. A Nafion membrane is modified by the incorporation of layered double hydroxide (LDH) nanoplatelets with different Mg 2+:Al 3+ ratios. When the feed concentration of methanol is lower than 3 M, the DMFC is controlled by the ionic conductivity of the polyelectrolyte membrane because methanol cross-over is not relatively significant. When the feed concentration is high, however, the diffusion coefficient of methanol is the key factor that determines the performance of the fuel cell. This is due to a high concentration gradient of methanol across the polyelectrolyte membrane. The open-circuit voltage is increased by the decreased diffusion coefficient in LDH/Nafion nanocomposite membranes at methanol feed concentrations up to 7 M; apparently because methanol cross-over is suppressed by the incorporation of LDH. The maximum power density of the DMFC is determined by the two competing transport processes of ion conduction and methanol diffusion, especially at a relatively high methanol concentration, that can provide optimum operating conditions in the membrane.

  8. First Detection of Methanol in a Class O Protostellar Disk

    NASA Astrophysics Data System (ADS)

    Velusamy, T.; Langer, William D.; Goldsmith, Paul F.

    2000-01-01

    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 O protostellar object. In addition, we identify a spectral feature in the outflow corresponding to an ethanol transition. Using the Caltech Owens Valley Millimeter Array with a synthesized beam size of 2", we detect spatially unresolved methanol in the 2k - 1k transitions at 3mm, which is coincident in position with the peak of the continuum emission. The gas phase methanol could be located in the central region (< 100 AU radius) of a flat disk, or in an extended heated surface layer (approx. 200 AU radius) of a flared disk. The fractional abundance of methanol X(CH3OH) is approx. 2 x l0-8 in the flat disk model, and 3 x l0-7 for the flared disk. The fractional abundance is small in the disk as a whole, but considerably larger in the warm portions. This difference indicates that substantial chemical processing probably takes place in the disk via depletion and desorption. The methanol desorbed from the grains in the warm surface layers returns to the icy grain mantles in the cooler interior of the disk, where it is available to become part of the composition of solar system-like bodies, such as comets, formed in the outer circumstellar region. This first millimeter-wavelength detection of a complex organic molecule in a young protostellar disk has implications for disk structure and chemical evolution and for potential use as a temperature probe. The research of TV and WL was conducted at the Jet Propulsion Laboratory, California Institute of Technology with support from the National Aeronautics and Space Administration.

  9. Excitation of the 51 - 60 A+ Methanol Transition

    NASA Astrophysics Data System (ADS)

    Kuiper, T. B. H.; Goldsmith, P.; de Gregorio Monsalvo, I.; Kalensky, S.; Peng, R.; Slysh, V.

    2009-01-01

    We are conducting an investigation of the excitation of the 6.7 GHz methanol maser line to determine the physical conditions that produce the inversion in this strongest of methanol masers. We have observed the ΔJ = -1, ΔK = 0 transitions at 290.1, 287.7 and 239.7 GHz, which connect to the levels of the maser line, towards a sample of strong Class II masers. The observations of the 51-41 A+ line at 239.7 GHz and 60-50 A+ line at 290.1 GHz make it possible to determine the relative populations (excitation temperature) of the 6.7 GHz maser levels. The derived excitation temperatures for the maser line, averaged over the 30" CSO beam, are in most cases positive. The lack of inversion suggests that the beam averages over regions with quasi-thermal and maser emission and that the regions which are inverted are much smaller than the CSO beam. A map of the W51 region in thermal methanol lines shows that the strongest masers occur at or near the peak of thermal methanol emission which indicates a correlation between methanol column density and maser intensity. We plan also to map the Orion OMC-1 region, where the mm emission is intense but the 6.7 GHz emission fairly weak and, interestingly, extended. The DR21 region also has mm emission strong enough to be mapped in reasonable time. Our colleague and friend Slava Slysh passed away in September. We miss his inspiring insights and dedicate this work to his memory. The work by TBHK and PFG was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract to the National Aeronautics and Space Administration.

  10. PATHOGENESIS OF METHANOL-INDUCED CRANIOFACIAL DEFECTS IN C57BL/6J MICE

    EPA Science Inventory

    BACKGROUND: Methanol administered to C57BL/6J mice during gastrulation causes severe craniofacial dysmorphology. We describe dysmorphogenesis, cell death, cell cycle assessment, and effects on development of cranial ganglia and nerves observed following administration of methanol...

  11. Spontaneous diabetes mellitus in transgenic mice expressing human islet amyloid polypeptide.

    PubMed Central

    Janson, J; Soeller, W C; Roche, P C; Nelson, R T; Torchia, A J; Kreutter, D K; Butler, P C

    1996-01-01

    The islet in non-insulin-dependent diabetes mellitus (NIDDM) is characterized by loss of beta cells and large local deposits of amyloid derived from the 37-amino acid protein, islet amyloid polypeptide (IAPP). We have hypothesized that IAPP amyloid forms intracellularly causing beta-cell destruction under conditions of high rates of expression. To test this we developed a homozygous transgenic mouse model with high rates of expression of human IAPP. Male transgenic mice spontaneously developed diabetes mellitus by 8 weeks of age, which was associated with selective beta-cell death and impaired insulin secretion. Small intra- and extracellular amorphous IAPP aggregates were present in islets of transgenic mice during the development of diabetes mellitus. However, IAPP derived amyloid deposits were found in only a minority of islets at approximately 20 weeks of age, notably after development of diabetes mellitus in male transgenic mice. Approximately 20% of female transgenic mice spontaneously developed diabetes mellitus at 30+ weeks of age, when beta-cell degeneration and both amorphous and amyloid deposits of IAPP were present. We conclude that overexpression of human IAPP causes beta-cell death, impaired insulin secretion, and diabetes mellitus. Large deposits of IAPP derived amyloid do not appear to be important in this cytotoxicity, but early, small amorphous intra- and extracellular aggregates of human IAPP were consistently present at the time of beta-cell death and therefore may be the most cytotoxic form of IAPP. Images Fig. 1 Fig. 3 Fig. 4 Fig. 5 PMID:8692984

  12. Methanol electro-oxidation on platinum modified tungsten carbides in direct methanol fuel cells: a DFT study.

    PubMed

    Sheng, Tian; Lin, Xiao; Chen, Zhao-Yang; Hu, P; Sun, Shi-Gang; Chu, You-Qun; Ma, Chun-An; Lin, Wen-Feng

    2015-10-14

    In exploration of low-cost electrocatalysts for direct methanol fuel cells (DMFCs), Pt modified tungsten carbide (WC) materials are found to be great potential candidates for decreasing Pt usage whilst exhibiting satisfactory reactivity. In this work, the mechanisms, onset potentials and activity for electrooxidation of methanol were studied on a series of Pt-modified WC catalysts where the bare W-terminated WC(0001) substrate was employed. In the surface energy calculations of a series of Pt-modified WC models, we found that the feasible structures are mono- and bi-layer Pt-modified WCs. The tri-layer Pt-modified WC model is not thermodynamically stable where the top layer Pt atoms tend to accumulate and form particles or clusters rather than being dispersed as a layer. We further calculated the mechanisms of methanol oxidation on the feasible models via methanol dehydrogenation to CO involving C-H and O-H bonds dissociating subsequently, and further CO oxidation with the C-O bond association. The onset potentials for the oxidation reactions over the Pt-modified WC catalysts were determined thermodynamically by water dissociation to surface OH* species. The activities of these Pt-modified WC catalysts were estimated from the calculated kinetic data. It has been found that the bi-layer Pt-modified WC catalysts may provide a good reactivity and an onset oxidation potential comparable to pure Pt and serve as promising electrocatalysts for DMFCs with a significant decrease in Pt usage. PMID:26351805

  13. Enhancing the methanol tolerance of platinum nanoparticles for the cathode reaction of direct methanol fuel cells through a geometric design

    NASA Astrophysics Data System (ADS)

    Feng, Yan; Ye, Feng; Liu, Hui; Yang, Jun

    2015-11-01

    Mastery over the structure of nanoparticles might be an effective way to enhance their performance for a given application. Herein we demonstrate the design of cage-bell nanostructures to enhance the methanol tolerance of platinum (Pt) nanoparticles while remaining their catalytic activity for oxygen reduction reaction. This strategy starts with the synthesis of core-shell-shell nanoparticles with Pt and silver (Ag) residing respectively in the core and inner shell regions, which are then agitated with saturated sodium chloride (NaCl) solution to eliminate the Ag component from the inner shell region, leading to the formation of bimetallic nanoparticles with a cage-bell structure, defined as a movable Pt core enclosed by a metal shell with nano-channels, which exhibit superior methanol-tolerant property in catalyzing oxygen reduction reaction due to the different diffusion behaviour of methanol and oxygen in the porous metal shell of cage-bell structured nanoparticles. In particular, the use of remarkably inexpensive chemical agent (NaCl) to promote the formation of cage-bell structured particles containing a wide spectrum of metal shells highlights its engineering merit to produce highly selective electrocatalysts on a large scale for the cathode reaction of direct methanol fuel cells.

  14. Enhancing the methanol tolerance of platinum nanoparticles for the cathode reaction of direct methanol fuel cells through a geometric design

    PubMed Central

    Feng, Yan; Ye, Feng; Liu, Hui; Yang, Jun

    2015-01-01

    Mastery over the structure of nanoparticles might be an effective way to enhance their performance for a given application. Herein we demonstrate the design of cage-bell nanostructures to enhance the methanol tolerance of platinum (Pt) nanoparticles while remaining their catalytic activity for oxygen reduction reaction. This strategy starts with the synthesis of core-shell-shell nanoparticles with Pt and silver (Ag) residing respectively in the core and inner shell regions, which are then agitated with saturated sodium chloride (NaCl) solution to eliminate the Ag component from the inner shell region, leading to the formation of bimetallic nanoparticles with a cage-bell structure, defined as a movable Pt core enclosed by a metal shell with nano-channels, which exhibit superior methanol-tolerant property in catalyzing oxygen reduction reaction due to the different diffusion behaviour of methanol and oxygen in the porous metal shell of cage-bell structured nanoparticles. In particular, the use of remarkably inexpensive chemical agent (NaCl) to promote the formation of cage-bell structured particles containing a wide spectrum of metal shells highlights its engineering merit to produce highly selective electrocatalysts on a large scale for the cathode reaction of direct methanol fuel cells. PMID:26578100

  15. Evaluation of dissociated and steam-reformed methanol as automotive engine fuels

    NASA Technical Reports Server (NTRS)

    Lalk, T. R.; Mccall, D. M.; Mccanlies, J. M.

    1984-01-01

    Dissociated and steam reformed methanol were evaluated as automotive engine fuels. Advantages and disadvantages in using methanol in the reformed rather than liquid state were discussed. Engine dynamometer tests were conducted with a four cylinder, 2.3 liter, spark ignition automotive engine to determine performance and emission characteristics operating on simulated dissociated and steam reformed methanol (2H2 + CO and 3H2 + CO2 respectively), and liquid methanol. Results are presented for engine performance and emissions as functions of equivalence ratio, at various throttle settings and engine speeds. Operation on dissociated and steam reformed methanol was characterized by flashback (violent propagation of a flame into the intake manifold) which limited operation to lower power output than was obtainable using liquid methanol. It was concluded that: an automobile could not be operated solely on dissociated or steam reformed methanol over the entire required power range - a supplementary fuel system or power source would be necessary to attain higher powers; the use of reformed mechanol, compared to liquid methanol, may result in a small improvement in thermal efficiency in the low power range; dissociated methanol is a better fuel than steam reformed methanol for use in a spark ignition engine; and use of dissociated or steam reformed methanol may result in lower exhaust emissions compared to liquid methanol.

  16. (14)C METHANOL INCORPORATION INTO DNA AND SPECIFIC PROTEINS OF ORGANOGENESIS STAGE MOUSE EMBRYOS IN VITRO

    EPA Science Inventory

    Methanol (MeOH), a widely used industrial solvent and alternative motor fuel, has been shown to be mutagenic and teratogenic. We have demonstrated that methanol is teratogenic in mice in vivo and causes dysmorphogenesis in cultured organogenesis stage mouse embryos. Methanol is ...

  17. 26 CFR 48.4041-20 - Partially exempt methanol and ethanol fuel.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 16 2010-04-01 2010-04-01 true Partially exempt methanol and ethanol fuel. 48... Partially exempt methanol and ethanol fuel. (a) In general. Under section 4041(m), the sale or use of partially exempt methanol or ethanol fuel is taxed at the rate of 41/2 cents per gallon of fuel sold or...

  18. A closer study of methanol adsorption and its impact on solute retentions in supercritical fluid chromatography.

    PubMed

    Glenne, Emelie; Öhlén, Kristina; Leek, Hanna; Klarqvist, Magnus; Samuelsson, Jörgen; Fornstedt, Torgny

    2016-04-15

    Surface excess adsorption isotherms of methanol on a diol silica adsorbent were measured in supercritical fluid chromatography (SFC) using a mixture of methanol and carbon dioxide as mobile phase. The tracer pulse method was used with deuterium labeled methanol as solute and the tracer peaks were detected using APCI-MS over the whole composition range from neat carbon dioxide to neat methanol. The results indicate that a monolayer (4Å) of methanol is formed on the stationary phase. Moreover, the importance of using the set or the actual methanol fractions and volumetric flows in SFC was investigated by measuring the mass flow respective pressure and by calculations of the actual volume fraction of methanol. The result revealed a significant difference between the value set and the actually delivered volumetric methanol flow rate, especially at low modifier fractions. If relying only on the set methanol fraction in the calculations, the methanol layer thickness should in this system be highly overestimated. Finally, retention times for a set of solutes were measured and related to the findings summarized above concerning methanol adsorption. A strongly non-linear relationship between the logarithms of the retention factors and the modifier fraction in the mobile phase was revealed, prior to the established monolayer. At modifier fractions above that required for establishment of the methanol monolayer, this relationship turns linear which explains why the solute retention factors are less sensitive to changes in modifier content in this region.

  19. A closer study of methanol adsorption and its impact on solute retentions in supercritical fluid chromatography.

    PubMed

    Glenne, Emelie; Öhlén, Kristina; Leek, Hanna; Klarqvist, Magnus; Samuelsson, Jörgen; Fornstedt, Torgny

    2016-04-15

    Surface excess adsorption isotherms of methanol on a diol silica adsorbent were measured in supercritical fluid chromatography (SFC) using a mixture of methanol and carbon dioxide as mobile phase. The tracer pulse method was used with deuterium labeled methanol as solute and the tracer peaks were detected using APCI-MS over the whole composition range from neat carbon dioxide to neat methanol. The results indicate that a monolayer (4Å) of methanol is formed on the stationary phase. Moreover, the importance of using the set or the actual methanol fractions and volumetric flows in SFC was investigated by measuring the mass flow respective pressure and by calculations of the actual volume fraction of methanol. The result revealed a significant difference between the value set and the actually delivered volumetric methanol flow rate, especially at low modifier fractions. If relying only on the set methanol fraction in the calculations, the methanol layer thickness should in this system be highly overestimated. Finally, retention times for a set of solutes were measured and related to the findings summarized above concerning methanol adsorption. A strongly non-linear relationship between the logarithms of the retention factors and the modifier fraction in the mobile phase was revealed, prior to the established monolayer. At modifier fractions above that required for establishment of the methanol monolayer, this relationship turns linear which explains why the solute retention factors are less sensitive to changes in modifier content in this region. PMID:26979267

  20. 26 CFR 48.4041-20 - Partially exempt methanol and ethanol fuel.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 16 2012-04-01 2012-04-01 false Partially exempt methanol and ethanol fuel. 48... Partially exempt methanol and ethanol fuel. (a) In general. Under section 4041(m), the sale or use of partially exempt methanol or ethanol fuel is taxed at the rate of 41/2 cents per gallon of fuel sold or...