Acidities of Water and Methanol in Aqueous Solution and DMSO

Science.gov (United States)

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…

Ethanolamine properties and use for feedwater pH control: A pressurized water reactor case study

International Nuclear Information System (INIS)

Keeling, D.L.; Polidoroff, C.T.; Cortese, S.; Cushner, M.C.

1995-01-01

Ethanolamine (ETA) as a feedwater pH control additive has been recently used to minimize corrosion of secondary water components in the nuclear power industry pressurized water reactors (PWRs). The use of ETA is compared with ammonia. Relative volatility effects on various parts of the system are analyzed and chemistry changes are presented. Materials of construction and the use of existing plant equipment for ETA service are discussed. Properties of ETA as well as safety, storage and handling issues are compared with ammonia. Health d aquatic toxicity are reviewed. warnings, safety, handling guidelines, biodegradability an Diablo Canyon Power Plant used ammonia for pH control from 1985 until a change over to ETA in 1993/1994. Full flow condensate polishers that are required to protect the plant from saltwater cooling incursions limit the amount of pH additive. Iron levels in the secondary water systems are compared before and after changing to ETA and replacement of corrosion-susceptible piping. Iron reduction benefits are assessed along with other effects on the feedwater nozzles, low pressure turbine, polisher resin capacity and polisher regeneration system

Ethanolamine experience at Koeberg nuclear power station, South Africa

International Nuclear Information System (INIS)

Galt, K.J.; Caris, N.B.

2002-01-01

Following testing of ethanolamine as an alternative to ammonia on Unit 2 in 1997, Unit 1 of the Koeberg Nuclear Power Station was converted to ethanolamine in 1998. The Unit has now operated for just over one and a half cycle on ETA. The decision to change to ETA was made to achieve further reductions in feedwater iron transport. Koeberg has always operated ammonia/hydrazine AVT control and ran the feedwater pH at 9.6-9.7 before the changeover. The original pH levels were increased in response to concerns over flow-accelerated corrosion. A by product of reducing the FAC rates is a reduction in iron transport. Although nominally all-ferrous, there are a number of small copper-containing components and the Koeberg Engineering Department would not countenance a further increase in ammonia concentrations in case of copper transport to the SGs. This led to ethanolamine being selected as an alternative to ammonia. The Koeberg condensate polishing plant has been modified, largely to accommodate ETA operation, but is not currently operable in the modified configuration. It is therefore on standby while ETA is implemented. The SG blowdown demineralizers have begun to be operated past ammonia/ETA break, but optimisation is largely dependent on CPP availability in the modified configuration. This paper documents the Koeberg experience to date of operation under an ethanolamine-AVT regime. As one of the few plants outside of the USA to have changed to ethanolamine, it is hoped we can make a valuable contribution for other non-US plants considering such a move. (authors)

A cuboctahedral platinum (Pt79) nanocluster enclosed by well defined facets favours di-sigma adsorption and improves the reaction kinetics for methanol fuel cells.

Science.gov (United States)

Mahata, Arup; Choudhuri, Indrani; Pathak, Biswarup

2015-08-28

The methanol dehydrogenation steps are studied very systematically on the (111) facet of a cuboctahedral platinum (Pt79) nanocluster enclosed by well-defined facets. The various intermediates formed during the methanol decompositions are adsorbed at the edge and bridge site of the facet either vertically (through C- and O-centres) or in parallel. The di-sigma adsorption (in parallel) on the (111) facet of the nanocluster is the most stable structure for most of the intermediates and such binding improves the interaction between the substrate and the nanocluster and thus the catalytic activity. The reaction thermodynamics, activation barrier, and temperature dependent reaction rates are calculated for all the successive methanol dehydrogenation steps to understand the methanol decomposition mechanism, and these values are compared with previous studies to understand the catalytic activity of the nanocluster. We find the catalytic activity of the nanocluster is excellent while comparing with any previous reports and the methanol dehydrogenation thermodynamics and kinetics are best when the intermediates are adsorbed in a di-sigma manner.

Phase equilibria at low temperature for light hydrocarbons-methanol-water-acid gases mixtures: measurements and modelling; Equilibres de phases a basse temperature de systemes complexes CO{sub 2} - hydrocarbures legers - methanol - eau: mesures et modelisation

Energy Technology Data Exchange (ETDEWEB)

Ruffine, L.

2005-10-15

The need to develop and improve natural gas treatment processes is real. The petroleum industry usually uses separation processes which require phase equilibrium phenomena. Yet, the complexity of the phase equilibria involved results in a lack of data, which in turn limits the development of thermodynamic models. The first part of this work is devoted to experimental investigations for systems containing light hydrocarbons, methanol, water and acid gases. We present a new apparatus that was developed to measure vapor-liquid and vapor-liquid-liquid equilibria. It allowed us to obtain new phase composition data for the methanol-ethane binary system and different mixtures, and also to determine a part of the three phases equilibrium envelope of the same systems. In the second part of this work, we have developed a thermodynamic model based on the CPA equation of state. This choice may be justified by the presence of associating components like methanol, hydrogen sulfide and water in the systems. Such model is necessary for the design of gas treatment plants. Our model provides good results for phase equilibrium calculations for binaries systems without binary interaction parameter in many cases, and describes correctly the vapour-liquid and vapor-liquid-liquid equilibria for complex mixtures. (author)

Fractionation of deuterium and protium between water and methanol

International Nuclear Information System (INIS)

Rolston, J.H.; Gale, K.L.

1984-01-01

The overall deuterium-protium separation factor, α, between hydrogen gas and aqueous methanol mixtures has been measured over the full composition range at temperatures between 25 and 55 0 C. At each temperature α increases smoothly with increasing mole fraction of methanol but the values fall significantly below the straight line joining the separation factors for the methanol-hydrogen and water-hydrogen systems. The equilibrium constant, K 1 (1), for exchange of a deuterium atom tracer between the hydroxyl groups of methanol and liquid water, calculated from the values of α for each solution, is independent of composition within experimental error. The value of K 1 (1) at 25 0 C is 0.54 +/- 0.02, so that deuterium favors the methanol environment rather than water. The dependence of k 1 (1) on absolute temperature, T, is given by the expression 1n K 1 (1) = -0.776 + 52.6/T, which corresponds to a reaction enthalpy of -0.43 kJ mol -1 . 24 references, 2 figures, 2 tables

Water quality and MTBE water pollution; Evidenze di presenza di MTBE sulle acque sotterranee di aree a rischio

Energy Technology Data Exchange (ETDEWEB)

Buiatti, M.; Mascini, M.; Monanni, R. [Florence Univ., Florence (Italy). Centro Interdipartimentale Biotecnologie Agrarie Chimiche Industriali; Agati, L.; Bartoli, C.; Bolletti, P.; Cortonesi, B.; Martinelli, L. [Agenzia Regionale per la Protezione dell' Ambiente della Toscana, Florence (Italy); Filipponi, M.; Piangoloni, A. [Nuove Acque SpA,, Arezzo (Italy); Mancini, G. [Autorita' di ambito territoriale ottimale n.4, Arezzo (Italy)

2001-11-01

The research project, here presented, was defined with the aim of evaluating the eventual presence of MTBE and the possible relative impact in water destined to human use; the territorial valence of the project was extended to the competence region n. 4 of the Tuscany water authority (AATO n. 4). University of Florence, ARPAT, AATO n. 4 and Nuove Acque SpA, in this role of manager for the integrated water cycle in the country, have productively contributed to the project. [Italian] La Nuove Acque SpA, soggetto gestore del ciclo idrico integrato, l'Universita' degli Studi di Firenze, l'Agenzia Regionale per la Protezione Ambientale e l'Autorita' di Ambito Territoriale hanno realizzato un progetto di verifica e messa a punto delle metodologie analitiche per il monitoraggio delle eventuali presenze di MTBE nelle acque, con particolare riferimento agli acquiferi sotterranei.

Solvation of graphite oxide in water-methanol binary polar solvents

Energy Technology Data Exchange (ETDEWEB)

You, Shujie; Yu, Junchun; Sundqvist, Bertil; Talyzin, Alexandr V. [Department of Physics, Umeaa University, SE-901 87 Umeaa (Sweden)

2012-12-15

The phase transition between two solvated phases was studied by DSC for graphite oxide (GO) powders immersed in water-methanol mixtures of various compositions. GO forms solid solvates with two different compositions when immersed in methanol. Reversible phase transition between two solvate states due to insertion/desertion of methanol monolayer occurs upon temperature variations. The temperature point and the enthalpy ({Delta}H) of the phase transition are maximal for pure methanol and decrease linearly with increase of water fraction up to 30%. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Solution thermodynamics and preferential solvation of sulfamethazine in (methanol + water) mixtures

International Nuclear Information System (INIS)

Delgado, Daniel R.; Almanza, Ovidio A.; Martínez, Fleming; Peña, María A.; Jouyban, Abolghasem; Acree, William E.

2016-01-01

Highlights: • Solubility of sulfamethazine (SMT) was measured in (methanol + water) mixtures. • SMT solubility was correlated with Jouyban–Acree model. • Gibbs energy, enthalpy, and entropy of dissolution of SMT were calculated. • Non-linear enthalpy–entropy relationship was observed for SMT. • Preferential solvation of SMT by methanol was analyzed by using the IKBI method. - Abstract: The solubility of sulfamethazine (SMT) in {methanol (1) + water (2)} co-solvent mixtures was determined at five different temperatures from (293.15 to 313.15) K. The sulfonamide exhibited its highest mole fraction solubility in pure methanol (δ 1 = 29.6 MPa 1/2 ) and its lowest mole fraction solubility in water (δ 2 = 47.8 MPa 1/2 ) at each of the five temperatures studied. The Jouyban–Acree model was used to correlate/predict the solubility values. The respective apparent thermodynamic functions Gibbs energy, enthalpy, and entropy of solution were obtained from the solubility data through the van’t Hoff and Gibbs equations. Apparent thermodynamic quantities of mixing were also calculated for this drug using values of the ideal solubility reported in the literature. A non-linear enthalpy–entropy relationship was noted for SMT in plots of both the enthalpy vs. Gibbs energy of mixing and the enthalpy vs. entropy of mixing. These plots suggest two different trends according to the slopes obtained when the composition of the mixtures changes. Accordingly, the mechanism for SMT transfer processes in water-rich mixtures from water to the mixture with 0.70 in mass fraction of methanol is entropy driven. Conversely, the mechanism is enthalpy driven in mixtures whenever the methanol composition exceeds 0.70 mol fraction. An inverse Kirkwood–Buff integral analysis of the preferential solvation of SMT indicated that the drug is preferentially solvated by water in water-rich mixtures but is preferentially solvated by methanol in methanol-rich mixtures.

Murine elongation factor 1 alpha (EF-1 alpha) is posttranslationally modified by novel amide-linked ethanolamine-phosphoglycerol moieties. Addition of ethanolamine-phosphoglycerol to specific glutamic acid residues on EF-1 alpha

International Nuclear Information System (INIS)

Whiteheart, S.W.; Shenbagamurthi, P.; Chen, L.; Cotter, R.J.; Hart, G.W.

1989-01-01

Elongation Factor 1 alpha (EF-1 alpha), an important eukaryotic translation factor, transports charged aminoacyl-tRNA from the cytosol to the ribosomes during poly-peptide synthesis. Metabolic radiolabeling with [ 3 H] ethanolamine shows that, in all cells examined, EF-1 alpha is the major radiolabeled protein. Radiolabeled EF-1 alpha has an apparent Mr = 53,000 and a basic isoelectric point. It is cytosolic and does not contain N-linked oligosaccharides. Trypsin digestion of murine EF-1 alpha generated two major [ 3 H]ethanolamine-labeled peptides. Three peptides were sequenced and were identical to two distinct regions of the human EF-1 alpha protein. Blank sequencing cycles coinciding with glutamic acid in the human cDNA-derived sequence were also found to release [ 3 H]ethanolamine, and compositional analysis of these peptides confirmed the presence of glutamic acid. Dansylation analysis demonstrates that the amine group of the ethanolamine is blocked. These results indicate that EF-1 alpha is posttranslationally modified by the covalent attachment of ethanolamine via an amide bond to at least two specific glutamic acid residues (Glu-301 and Glu-374). The hydroxyl group of the attached ethanolamine was shown by mass spectrometry and compositional analysis, to be further modified by the addition of a phosphoglycerol unit. This novel posttranslational modification may represent an important alteration of EF-1 alpha, comparable to the regulatory effects of posttranslational methylation of EF-1 alpha lysine residues

Water Quality of NPP Secondary Side with Combined Water Chemistry of Ammonia and Ethanolamine

International Nuclear Information System (INIS)

Rhee, In-H.; Jung, Hyun-jun; Cho, Daechul; Park, Byunggi

2012-09-01

Ammonia (AM) and Ethanolamine (ETA), as pH control additive agents, were injected to the secondary side in a Korean NPP for the even pH in the entire secondary system including the wet region and the condensate. Ammonia and ETA are dominant in the vapor and liquid phases, respectively, since the former and latter are more and less volatile than water in the temperature range of 30 to 300 . pH of 9.5 to 9.7 was maintained in the water-steam cycle at the concentrations of ammonia with ∼1.0 ppm and ETA of ∼1.8 ppm. From the standpoint of corrosion, i.g, concentration of Fe, the water quality of secondary side was improved by the combined water treatment of ammonia and ETA, compared to all volatile treatment of ammonia. The electrical conductivity was increased from 6 to 10 μS/cm due to the presence of organic carboxylates produced by the decomposition of ETA. ETA was broken down by <5% in steam generator and converted into formate, acetate, and glycolate, among which acetate was largely formed. But inorganic ions such as Na + , Cl - , and SO 4 2- are not changed because their ingress was not made and the selectivity of resin over those ions was not fairly altered. The runtime of demineralizer in steam generator blowdown was shortened by a third for a mixture of ammonia and ETA. Most of Fe was originated from the shell side of heat exchangers including the condenser as a result of corrosion. Fe was only eliminated by ion exchange demineralizers, i.e., 46% at CPP and 3% at SG BD and 70% of Fe oxides were accumulated at the steam generator, on the basis of Fe concentration at the final feedwater. In conclusion, ETA is preferable to ammonia for the enhancement of pH in the liquid phase of water-steam mixture such as the shell side of heat exchanger and also the full-flow operation of CPP is more desirable than partial-flow operation for the improved removal of corrosion products, regardless of hydrogen- or amine-type operation. (authors)

Accumulation of N-acyl-ethanolamine phospholipids in rat brains during post-decapitative ischemia

DEFF Research Database (Denmark)

Moesgaard, B.; Hansen, Harald S.; Jaroszewski, J.W.

1999-01-01

-phospho(N-acyl)-ethanolamine (NAPE(PLAS)), respectively, by spiking with authentic materials. Additionally, the identification was verified by thin-layer chromatography, which also showed the accumulation of N-acyl-ethanolamine phospholipids. The use of K-EDTA instead of the commonly used Cs...

Hydrostatic pressure effect on PNIPAM cononsolvency in water-methanol solutions.

Science.gov (United States)

Pica, Andrea; Graziano, Giuseppe

2017-12-01

When methanol is added to water at room temperature and 1atm, poly (N-isopropylacrylamide), PNIPAM, undergoes a coil-to-globule collapse transition. This intriguing phenomenon is called cononsolvency. Spectroscopic measurements have shown that application of high hydrostatic pressure destroys PNIPAM cononsolvency in water-methanol solutions. We have developed a theoretical approach that identifies the decrease in solvent-excluded volume effect as the driving force of PNIPAM collapse on increasing the temperature. The same approach indicates that cononsolvency, at room temperature and P=1atm, is caused by the inability of PNIPAM to make all the attractive energetic interactions that it could be engaged in, due to competition between water and methanol molecules. The present analysis suggests that high hydrostatic pressure destroys cononsolvency because the coil state becomes more compact, and the quantity measuring PNIPAM-solvent attractions increases in magnitude due to the solution density increase, and the ability of small water molecules to substitute methanol molecules on PNIPAM surface. Copyright © 2017 Elsevier B.V. All rights reserved.

Thermal properties of phosphoric acid-doped polybenzimidazole membranes in water and methanol-water mixtures

Energy Technology Data Exchange (ETDEWEB)

Nores-Pondal, Federico J.; Corti, Horacio R. [Grupo de Pilas de Combustible, Departamento de Fisica de la Materia Condensada, Centro Atomico Constituyentes, Comision Nacional de Energia Atomica (CNEA), Av. General Paz 1499, B1650KNA San Martin, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (Argentina); Buera, M. Pilar [Consejo Nacional de Investigaciones Cientificas y Tecnicas (Argentina); Departamento de Industrias, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Av. Cantilo s/n, Ciudad Universitaria (1428) Buenos Aires (Argentina)

2010-10-01

The thermal properties of phosphoric acid-doped poly[2-2'-(m-phenylene)-5-5' bi-benzimidazole] (PBI) and poly[2,5-benzimidazole] (ABPBI) membranes, ionomeric materials with promising properties to be used as electrolytes in direct methanol and in high temperature polymer electrolyte membrane (PEM) fuel cells, were studied by means of differential scanning calorimetry (DSC) technique in the temperature range from -145 C to 200 C. The DSC scans of samples equilibrated in water at different relative humidities (RH) and in liquid water-methanol mixtures were analyzed in relation to glass transition, water crystallization/melting and solvent desorption in different temperature regions. The thermal relaxation observed in the very low temperature region could be ascribed to the glass transition of the H{sub 3}PO{sub 4}-H{sub 2}O mixture confined in the polymeric matrix. After cooling the samples up to -145 C, frozen water was detected in PBI and ABPBI at different RH, although at 100% RH less amount of water had crystallized than that observed in Nafion membranes under the same conditions. Even more important is the fact that the freezing degree of water is much lower in ABPBI membranes equilibrated in liquid water-methanol mixtures than that observed for PBI and, in a previous study, for Nafion. Thus, apart from other well known properties, acid-doped ABPBI emerges as an excellent ionomer for applications in direct methanol fuel cells working in cold environments. (author)

Electrokinetic transport of water and methanol in Nafion membranes as observed by NMR spectroscopy

International Nuclear Information System (INIS)

Hallberg, Fredrik; Vernersson, Thomas; Pettersson, Erik Thyboll; Dvinskikh, Sergey V.; Lindbergh, Goeran; Furo, Istvan

2010-01-01

Electrophoretic NMR (eNMR) and pulsed-field-gradient NMR (PFG-NMR) methods were used to study transport processes in situ and in a chemically resolved manner in the electrolyte of an experimental direct methanol fuel cell (DMFC) setup, constituted of several layers of Nafion 117. The measurements were conducted at room temperature for membranes fully swollen by methanol-water mixtures over a wide concentration interval. The experimental setup and the experimental protocol for the eNMR experiments are discussed in detail. The magnitude of the water and methanol self-diffusion coefficients show a good agreement with previously published data while the ratio of the two self-diffusion coefficients may indicate an imperfect mixing of the two solvent molecules. On the molecular level, the drag of water and methanol molecules by protons is roughly of the same magnitude, with the drag of methanol molecules increasing with increasing methanol content. The electro-osmotic drag defined on mass-flow basis increased for methanol from a low level with increasing methanol concentration while that of water remained roughly constant.

Comparison of ethanolamine and potassium hydroxide as quantitative trapping agents for radiolabeled CO2 in metabolism studies

International Nuclear Information System (INIS)

Medinsky, M.A.

1986-01-01

The efficiency of ethanolamine and potassium hydroxide (KOH) as trapping agents for CO 2 was determined using a flow of 500 mL/min through CO 2 absorption towers containing trapping solution. Radiolabeled 14 CO 2 was produced by acidification of suspensions containing Ba 14 CO 3 . Both 100% ethanolamine and 5M ethanolamine in 2-methoxyethanol were evaluated. With 200 mL of either solution, trapping efficiency of 14 CO 2 decreased when only 5% or less of the amount of ethanolamine available had reacted (22 mmoles of CO 2 ) trapped). In contrast, use of 200 mL of 1M or 5M KOH was effective in retaining 88 mmoles of CO 2 . This is equivalent to the amount of CO 2 produced by a rat over an 8-hr period. In summary, with flow rates commonly used in in vivo metabolism studies, the trapping efficiency of ethanolamine was far less than the theoretical efficiency. In these types of studies KOH would be a more suitable trapping agent or, if used, ethanolamine solutions must be changed frequently

Vapor-Liquid Equilibrium of Methane with Water and Methanol. Measurements and Modeling

DEFF Research Database (Denmark)

Frost, Michael Grynnerup; Karakatsani, Eirini; von Solms, Nicolas

2014-01-01

that rely on phase equilibrium data for optimization. The objective of this work is to provide experimental data for hydrocarbon systems with polar chemicals such as alcohols, glycols, and water. New vapor-liquid equilibrium data are reported for methane + water, methane + methanol, and methane + methanol...

Crystal structure of di-μ-chlorido-bis[dichloridobis(methanol-κOiridium(III] dihydrate: a surprisingly simple chloridoiridium(III dinuclear complex with methanol ligands

Directory of Open Access Journals (Sweden)

Joseph S. Merola

2015-05-01

Full Text Available The reaction between IrCl3·xH2O in methanol led to the formation of small amounts of the title compound, [Ir2Cl6(CH3OH4]·2H2O, which consists of two IrCl4O2 octahedra sharing an edge via chloride bridges. The molecule lies across an inversion center. Each octahedron can be envisioned as being comprised of four chloride ligands in the equatorial plane with methanol ligands in the axial positions. A lattice water molecule is strongly hydrogen-bonded to the coordinating methanol ligands and weak interactions with coordinating chloride ligands lead to the formation of a three-dimensional network. This is a surprising structure given that, while many reactions of iridium chloride hydrate are carried out in alcoholic solvents, especially methanol and ethanol, this is the first structure of a chloridoiridium compound with only methanol ligands.

An ethanolamine kinase Eki1 affects radial growth and cell wall integrity in Trichoderma reesei.

Science.gov (United States)

He, Ronglin; Guo, Wei; Zhang, Dongyuan

2015-09-01

Ethanolamine kinase (ATP:ethanolamine O-phosphotransferase, EC 2.7.1.82) catalyzes the committed step of phosphatidylethanolamine synthesis via the CDP-ethanolamine pathway. The functions of eki genes that encode ethanolamine kinase have been intensively studied in mammalian cells, fruit flies and yeast. However, the role of the eki gene has not yet been characterized in filamentous fungi. In this study, Treki1, an ortholog of Saccharomyces cerevisiae EKI1, was identified and functionally characterized using a target gene deletion strategy in Trichoderma reesei. A Treki deletion mutant was less sensitive to cell wall stressors calcofluor white and Congo red and released fewer protoplasts during cell wall digestion than the parent strain QM9414. Further transcription analysis showed that the expression levels of five genes that encode chitin synthases were drastically increased in the ΔTreki1 mutant. The chitin content was also increased in the null mutant of Treki1 comparing to the parent strain. In addition, the ΔTreki1 mutant exhibited defects in radial growth, conidiation and the accumulation of ethanolamine. The results indicate that Treki1 plays a key role in growth and development and in the maintenance of cell wall integrity in T. reesei. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Influencing parameters of water and methanol transport in a big direct methanol fuel cell; Einflussgroessen auf den Wasser- und Methanoltransport einer groesseren Direkt-Methanol Brennstoffzelle

Energy Technology Data Exchange (ETDEWEB)

Schonert, Morten

2008-07-01

The author investigated the influencing parameters of water and methanol transport in a big direct methanol fuel cell (Pel > 1 kW) with the intention of making the direct methanol fuel cell system water-autonomous. As water is consumed during the electrochemical reaction on the anode while more water is produced on the cathode, the difference must be removed via the air. Any further water produced on the cathode must be condensed and recirculated to the anode. With increasing ambient temperature, the air volume flow must be reduced because otherwise more water would be removed than is acceptable. Low air volume flow on the cathode causes unstable cell voltage, which is also assumed to be caused by excess water production. For this reason, an attempt was made to prevent excess water production on the cathode by a system engineering approach. It was found that at the low air volume flow required for water autonomy, water permeation through the membrane-electrode aggregate (MEA) depends on the uptake capacity and on the time of residue of air over the cathode and less on the cathode material. Water permeation stops when the concentration gradient is balanced. Apart from the water permeation, there is also water transport through the Nafion {sup registered} membrane, i.e. so-called electroosmotic drag (ESD). This is an active transport mechanism that can also work against a concentration gradient. It could be shown that the EOD can be reduced by using water-impermeable materials for the gas diffusion layer on the anode. This will reduce the water volume that reaches the membrane, i.e. the water on the cathode. On the other hand, there was no measurable effect of the cathode design on water or methanol transport. The electrochemical performance of the membrane-electrode units under investigation was robust in case of many influencing parameters, e.g. dispersion, the conditions of MEA fabrication by hot pressing, themembrane thickness and the rate of methanol permeation

Introduction à la thermodynamique cours et problèmes résolus

CERN Document Server

Lhuillier, Claire

1994-01-01

Si la thermodynamique fait appel à des concepts comme l'entropie, son étude renvoie souvent à des phénomènes courants (les changements d'état) ou encore à des technologies lourdes (les centrales thermiques). De ce fait, on la considère parfois comme une discipline difficile d'accès. Dans le cadre de leur enseignement de première année de premier cycle, Claire LHUILLIER et Jean ROUS ont rédigé un cours - appuyé de très nombreux exemples - dans lesquels ils introduisent avec clarté et rigueur toutes les notions de base : pression, température, énergie interne, premier principe, travail des forces de pression, chaleurs, etc. L'introduction de l'entropie est dissociée de celle du second principe : c'est une fonction d'état qui mesure l'information microscopique manquante. Le second principe est alors formulé comme un principe d'évolution, adapté à l'étude des phénomènes irréversibles. Les potentiels thermodynamiques ont été plus longuement traités dans cette nouvelle édition. Une f...

Unbiased water and methanol maser surveys of NGC 1333

Energy Technology Data Exchange (ETDEWEB)

Lyo, A-Ran; Kim, Jongsoo; Byun, Do-Young; Lee, Ho-Gyu, E-mail: arl@kasi.re.kr [Korea Astronomy and Space Science Institute, 776, Daedeokdae-ro Yuseong-gu, Daejeon 305-348 (Korea, Republic of)

2014-11-01

We present the results of unbiased 22 GHz H{sub 2}O water and 44 GHz class I CH{sub 3}OH methanol maser surveys in the central 7' × 10' area of NGC 1333 and two additional mapping observations of a 22 GHz water maser in a ∼3' × 3' area of the IRAS4A region. In the 22 GHz water maser survey of NGC 1333 with a sensitivity of σ ∼ 0.3 Jy, we confirmed the detection of masers toward H{sub 2}O(B) in the region of HH 7-11 and IRAS4B. We also detected new water masers located ∼20'' away in the western direction of IRAS4B or ∼25'' away in the southern direction of IRAS4A. We could not, however, find young stellar objects or molecular outflows associated with them. They showed two different velocity components of ∼0 and ∼16 km s{sup –1}, which are blue- and redshifted relative to the adopted systemic velocity of ∼7 km s{sup –1} for NGC 1333. They also showed time variabilities in both intensity and velocity from multi-epoch observations and an anti-correlation between the intensities of the blue- and redshifted velocity components. We suggest that the unidentified power source of these masers might be found in the earliest evolutionary stage of star formation, before the onset of molecular outflows. Finding this kind of water maser is only possible through an unbiased blind survey. In the 44 GHz methanol maser survey with a sensitivity of σ ∼ 0.5 Jy, we confirmed masers toward IRAS4A2 and the eastern shock region of IRAS2A. Both sources are also detected in 95 and 132 GHz methanol maser lines. In addition, we had new detections of methanol masers at 95 and 132 GHz toward IRAS4B. In terms of the isotropic luminosity, we detected methanol maser sources brighter than ∼5 × 10{sup 25} erg s{sup –1} from our unbiased survey.

Studies of the role of water in the electrocatalysis of methanol oxidation

Science.gov (United States)

Lin, Andrew S.; Kowalak, Albert D.; O'Grady, William E.

The oxidation of methanol has been carried out on electrodes prepared by evaporating Pt directly onto a Nafion membrane and then introducing the methanol either in the gas-fed mode or directly from the electrolyte in the electrolyte-fed mode. It was found that the oxidation carried out using a gas-fed electrode was shifted 100-150 mV more cathodic than the electrolyte-fed electrode. A similar set of experiments was carried out using hydrophobic gas-diffusion electrodes and similar results were obtained. These results suggest that the mechanism of the methanol oxidation reaction depends on the nature of the surroundings and the orientation of the methanol with respect to the electrode surface. In the electrolyte-fed configuration the methanol will be in a hydrogen-bonded water cluster allowing the carbon end of the molecule to more readily approach the catalyst surface. While in the gas-fed configuration the methanol will interact with the water or oxidic surface through the hydroxyl end of the molecule. Clearly, these two possible mechanisms will lead to different products and one may enhance the rate of the direct oxidation of methanol as observed in this work.

Gradients in microbial methanol uptake: productive coastal upwelling waters to oligotrophic gyres in the Atlantic Ocean

Science.gov (United States)

Dixon, Joanna L; Sargeant, Stephanie; Nightingale, Philip D; Colin Murrell, J

2013-01-01

Methanol biogeochemistry and its importance as a carbon source in seawater is relatively unexplored. We report the first microbial methanol carbon assimilation rates (k) in productive coastal upwelling waters of up to 0.117±0.002 d−1 (∼10 nmol l−1 d−1). On average, coastal upwelling waters were 11 times greater than open ocean northern temperate (NT) waters, eight times greater than gyre waters and four times greater than equatorial upwelling (EU) waters; suggesting that all upwelling waters upon reaching the surface (⩽20 m), contain a microbial population that uses a relatively high amount of carbon (0.3–10 nmol l−1 d−1), derived from methanol, to support their growth. In open ocean Atlantic regions, microbial uptake of methanol into biomass was significantly lower, ranging between 0.04–0.68 nmol l−1 d−1. Microbes in the Mauritanian coastal upwelling used up to 57% of the total methanol for assimilation of the carbon into cells, compared with an average of 12% in the EU, and 1% in NT and gyre waters. Several methylotrophic bacterial species were identified from open ocean Atlantic waters using PCR amplification of mxaF encoding methanol dehydrogenase, the key enzyme in bacterial methanol oxidation. These included Methylophaga sp., Burkholderiales sp., Methylococcaceae sp., Ancylobacter aquaticus, Paracoccus denitrificans, Methylophilus methylotrophus, Methylobacterium oryzae, Hyphomicrobium sp. and Methylosulfonomonas methylovora. Statistically significant correlations for upwelling waters between methanol uptake into cells and both chlorophyll a concentrations and methanol oxidation rates suggest that remotely sensed chlorophyll a images, in these productive areas, could be used to derive total methanol biological loss rates, a useful tool for atmospheric and marine climatically active gas modellers, and air–sea exchange scientists. PMID:23178665

Model-based analysis of water management in alkaline direct methanol fuel cells

Science.gov (United States)

Weinzierl, C.; Krewer, U.

2014-12-01

Mathematical modelling is used to analyse water management in Alkaline Direct Methanol Fuel Cells (ADMFCs) with an anion exchange membrane as electrolyte. Cathodic water supply is identified as one of the main challenges and investigated at different operation conditions. Two extreme case scenarios are modelled to study the feasible conditions for sufficient water supply. Scenario 1 reveals that water supply by cathodic inlet is insufficient and, thus, water transport through membrane is essential for ADMFC operation. The second scenario is used to analyse requirements on water transport through the membrane for different operation conditions. These requirements are influenced by current density, evaporation rate, methanol cross-over and electro-osmotic drag of water. Simulations indicate that water supply is mainly challenging for high current densities and demands on high water diffusion are intensified by water drag. Thus, current density might be limited by water transport through membrane. The presented results help to identify important effects and processes in ADMFCs with a polymer electrolyte membrane and to understand these processes. Furthermore, the requirements identified by modelling show the importance of considering water transport through membrane besides conductivity and methanol cross-over especially for designing new membrane materials.

Historique en grandes enjambées de la thermodynamique de l'équilibre

Science.gov (United States)

Hertz, J.

2004-12-01

La Thermodynamique, une science totalement nouvelle au XIXème siècle, a germé en France en contrepoint des idées du siècle des Lumières, dans le milieu particulier des anciens élèves de l’Ecole Polytechnique, officiers supérieurs formés pour l’armée républicaine ou napoléonienne, mais qui ne trouvaient plus leur place dans l’armée de la Restauration. Ils se convertissaient en ingénieurs civils des métiers industriels en pleine expansion, comme le développement de la machine à vapeur ou des chemins de fer. La plupart d’entre eux, plutôt libre-penseurs, adhéraient aux idées scientistes du « positivisme », véhiculées dans les Loges de la Franc-Maçonnerie du Grand Orient de France et plus particulièrement dans les cercles Saint-Simoniens, premiers adeptes du socialisme industriel. C’est ainsi que naquit en 1824, dans le cerveau subtil mais brouillon de Sadi Carnot toute la vision illuminée de cette science nouvelle, incompréhensible pour ses contemporains. Elle ressuscita en 1834 sous la plume d’un Emile Clapeyron qui avait pris conscience de l’immensité de l’œuvre de Sadi Carnot. Mais le rappel de Clapeyron demeura également sans écho pendant dix années. Le réveil de la Thermodynamique se fera désormais hors de France par des hommes de grande pratique religieuse et généralement protestants. C’est ainsi que William Thomson en Ecosse et Rudolph Clausius, venu de Prusse, achevèrent l’œuvre de leurs deux prédécesseurs et que la Thermodynamique mécano-thermique fut définitivement établie en 1864. La thermodynamique chimique peut être attribuée à un seul génie mathématicien, Josiah Willard Gibbs qui travaillait tout seul au Yale College de New-Haven, dans le Connecticut, et rédigea sa nouvelle théorie entre 1875 et 1878. Enfin l’interprétation statistique du second principe sera l’œuvre en 1877 d’un Autrichien, Ludwig Boltzmann, homme génial mais fragile qui eut le temps d’insuffler ses id

Production of synthetic methanol from air and water using controlled thermonuclear reactor power

International Nuclear Information System (INIS)

Dang, V.D.; Steinberg, M.

1977-01-01

Energy requirement and process development of methanol production from air and water using controlled thermonuclear fusion power was discussed in Part 1 (Steinberg et al., Energy conversion;17:97(1977)). This second part presents an economic analysis of the nine processes presented for obtaining carbon dioxide recovery from the atmosphere or the sea for methanol production. It is found that the most economical process of obtaining carbon dioxide is by stripping from sea water. The process of absorption/stripping by dilute potassium carbonate solution is found to be the most economical for the extraction of carbon dioxide from air at atmospheric pressure. The total energy required for methanol synthesis from these sources of carbon dioxide is 3.90 kWh(e)/lb methanol of which 90% is used for generation of hydrogen. The process which consumes the greatest amount of energy is the absorption/stripping of air by water at high pressure and amounts to 13.2 kWh(e)/lb methanol. With nuclear fusion power plants of 1000to 9000 MW(e), it is found that the cost of methanol using the extraction of carbon dioxide from air with dilute potassium carbonate solution is estimated to be in the range between Pound1.73 and Pound2.90/MMB.t.u. (energy equivalent - 1974 cost) for plant capacities of 21 400 to 193 000 bbl/day methanol. This methanol cost is competitive with gasoline in the range of 19 approximately equal to 33c/gallon. For the process of stripping of carbon dioxide from sea water, the cost is found to lie in the range of Pound1.65 to Pound2.71/MMB.t.u. (energy equivalent) for plant capacities of 21 700 to 195 000 bbl/day methanol which is competitive with gasoline in the range of 18 approximately equal to 30 c/gallon. Projection of methanol demand in the year 2020 is presented based on both its conventional use as chemicals and as a liquid fuel substituting for oil and gas. (author)

The use of 14C ethanolamine as a precursor

International Nuclear Information System (INIS)

Madelmont, J.C.; Parry, D.; Godeneche, D.; Duprat, J.

1985-01-01

Two new 2 chloroethyl nitrosoureas were labelled on two positions by 14 C starting from Na 14 CN and using 14 C ethanolamine as intermediate, i.e. on the carbon 2 of the 2 chloro ethyl group and on the carbon 2 of the cysteamine part. (author)

Comparison of the SRK and CPA equations of state for physical properties of water and methanol

DEFF Research Database (Denmark)

Lundstrøm, Carsten; Michelsen, Michael Locht; Kontogeorgis, Georgios

2006-01-01

produced together with water, properties of water and additives like methanol and glycol is another target area. Being more polar than hydrocarbons, water, alcohols and glycols may require more advanced models for example an association model like CPA (CubicPlus-Association). This type of model has...... previously been found to be well suited for phase equilibrium calculations on mixtures of hydrocarbons and polar compounds. In this work, SRK (with and without Peneloux volume correction) and CPA are compared for pure water, pure methanol and water-methanol binary mixtures with the purpose of evaluating...

A CNT (carbon nanotube) paper as cathode gas diffusion electrode for water management of passive μ-DMFC (micro-direct methanol fuel cell) with highly concentrated methanol

International Nuclear Information System (INIS)

Deng, Huichao; Zhang, Yufeng; Zheng, Xue; Li, Yang; Zhang, Xuelin; Liu, Xiaowei

2015-01-01

A novel MEA (membrane electrode assembly) structure of passive μ-DMFC (micro-direct methanol fuel cell) controls water management and decreases methanol crossover. The CNT (carbon nanotube) paper replacing CP (carbon paper) as GDL (gas diffusion paper) enhances water back diffusion which passively prevents flooding in the cathode and promotes low methanol crossover. Moreover, the unique structure of CNT paper can also enhance efficiency of oxygen mass transport and catalyst utilization. The passive μ-DMFC with CNT-MEA exhibits significantly higher performance than passive μ-DMFC with CP-MEA and can operate in high methanol concentration, showing the peak power density of 23.2 mW cm −2 . The energy efficiency and fuel utilization efficiency are obviously improved from 11.54% to 22.7% and 36.61%–49.34%, respectively, and the water transport coefficient is 0.47 which is lower than previously reported passive μ-DMFC with CP. - Highlights: • This novel GDL (gas diffusion layer) solves water management and methanol crossover. • This GDL creates a hydraulic pressure in the cathode increasing water back diffusion. • This GDL improves the electrical conductivity and activity of catalyst

Terahertz sensing of highly absorptive water-methanol mixtures with multiple resonances in metamaterials.

Science.gov (United States)

Chen, Min; Singh, Leena; Xu, Ningning; Singh, Ranjan; Zhang, Weili; Xie, Lijuan

2017-06-26

Terahertz sensing of highly absorptive aqueous solutions remains challenging due to strong absorption of water in the terahertz regime. Here, we experimentally demonstrate a cost-effective metamaterial-based sensor integrated with terahertz time-domain spectroscopy for highly absorptive water-methanol mixture sensing. This metamaterial has simple asymmetric wire structures that support multiple resonances including a fundamental Fano resonance and higher order dipolar resonance in the terahertz regime. Both the resonance modes have strong intensity in the transmission spectra which we exploit for detection of the highly absorptive water-methanol mixtures. The experimentally characterized sensitivities of the Fano and dipole resonances for the water-methanol mixtures are found to be 160 and 305 GHz/RIU, respectively. This method provides a robust route for metamaterial-assisted terahertz sensing of highly absorptive chemical and biochemical materials with multiple resonances and high accuracy.

Etude de pratiques d'enseignement relatives a la modelisation en sciences et technologies avec des enseignants du secondaire

Science.gov (United States)

Aurousseau, Emmanuelle

Les modeles sont des outils amplement utilises en sciences et technologies (S&T) afin de representer et d’expliquer un phenomene difficilement accessible, voire abstrait. La demarche de modelisation est presentee de maniere explicite dans le programme de formation de l’ecole quebecoise (PFEQ), notamment au 2eme cycle du secondaire (Quebec. Ministere de l'Education du Loisir et du Sport, 2007a). Elle fait ainsi partie des sept demarches auxquelles eleves et enseignants sont censes recourir. Cependant, de nombreuses recherches mettent en avant la difficulte des enseignants a structurer leurs pratiques d’enseignement autour des modeles et de la demarche de modelisation qui sont pourtant reconnus comme indispensables. En effet, les modeles favorisent la conciliation des champs concrets et abstraits entre lesquels le scientifique, meme en herbe, effectue des allers-retours afin de concilier le champ experimental de reference qu’il manipule et observe au champ theorique relie qu’il construit. L’objectif de cette recherche est donc de comprendre comment les modeles et la demarche de modelisation contribuent a faciliter l’articulation du concret et de l’abstrait dans l’enseignement des sciences et des technologies (S&T) au 2eme cycle du secondaire. Pour repondre a cette question, nous avons travaille avec les enseignants dans une perspective collaborative lors de groupes focalises et d’observation en classe. Ces dispositifs ont permis d’examiner les pratiques d’enseignement que quatre enseignants mettent en oeuvre en utilisant des modeles et des demarches de modelisation. L’analyse des pratiques d’enseignement et des ajustements que les enseignants envisagent dans leur pratique nous permet de degager des connaissances a la fois pour la recherche et pour la pratique des enseignants, au regard de l’utilisation des modeles et de la demarche de modelisation en S&T au secondaire.

Ejection of solvated ions from electrosprayed methanol/water nanodroplets studied by molecular dynamics simulations.

Science.gov (United States)

Ahadi, Elias; Konermann, Lars

2011-06-22

The ejection of solvated small ions from nanometer-sized droplets plays a central role during electrospray ionization (ESI). Molecular dynamics (MD) simulations can provide insights into the nanodroplet behavior. Earlier MD studies have largely focused on aqueous systems, whereas most practical ESI applications involve the use of organic cosolvents. We conduct simulations on mixed water/methanol droplets that carry excess NH(4)(+) ions. Methanol is found to compromise the H-bonding network, resulting in greatly increased rates of ion ejection and solvent evaporation. Considerable differences in the water and methanol escape rates cause time-dependent changes in droplet composition. Segregation occurs at low methanol concentration, such that layered droplets with a methanol-enriched periphery are formed. This phenomenon will enhance the partitioning of analyte molecules, with possible implications for their ESI efficiencies. Solvated ions are ejected from the tip of surface protrusions. Solvent bridging prior to ion secession is more extensive for methanol/water droplets than for purely aqueous systems. The ejection of solvated NH(4)(+) is visualized as diffusion-mediated escape from a metastable basin. The process involves thermally activated crossing of a ~30 kJ mol(-1) free energy barrier, in close agreement with the predictions of the classical ion evaporation model.

ESR study of the effects of water, methanol, and ethanol on gamma-irradiation of starch

International Nuclear Information System (INIS)

Henderson, A.M.; Rudin, A.

1981-01-01

This investigation deals with the nature and relative abundance of stable radicals formed by gamma-irradiation of wheat starch at room temperature. Additions of equal weights of water, methanol, and ethanol were equally effective in reducing the content of stable radicals in starch which contained about 12% water before the additions. When, however, the starting material was dried starch with 2.9% initial water content additional water and methanol were better radical scavengers than ethanol. This difference is attributed to the superior ability of water and methanol to permeate the starch structure. Superficially different ESR spectra were obtained in products made by irradiating starch and starch that contained added water or methanol. Computer simulation of these spectra showed that they could be matched by superposition of the spectra of the same four component radicals, with some adjustments of relative intensities and peak widths. The structure of these radicals have been deduced from the spectral assignments and relative effects of the three solvents used on the intensities of the respective ESR spectra

Comparison of ethanolamine and potassium hydroxide as quantitative trapping agents for radiolabeled CO2 in metabolism studies

International Nuclear Information System (INIS)

Medinsky, M.A.

1984-01-01

The efficiency of ethanolamine and potassium hydroxide as trapping agents for CO 2 was tested using a flow of 500 ml/min through CO 2 absorption towers containing trapping solutions. Radiolabeled CO 2 was produced by acidification of suspensions containing Ba 14 CO 3 . With 200 ml of ethanolamine, trapping efficiency of 14 CO 2 decreased when only 5% or less of the amount of ethanolamine available had reacted (22 mmoles of CO 2 trapped). In contrast, use of 200 ml of 1 M or 5 M KOH was effective in retaining 88 mmoles of CO 2 . This is equivalent to the amount of CO 2 produced by a rat over an 8-hour period

Solubility and preferential solvation of some n-alkyl-parabens in methanol + water mixtures at 298.15 K

International Nuclear Information System (INIS)

Cárdenas, Zaira J.; Jiménez, Daniel M.; Delgado, Daniel R.; Almanza, Ovidio A.; Jouyban, Abolghasem; Martínez, Fleming; Acree, William E.

2017-01-01

Highlights: • Parabens equilibrium solubility was determined in methanol + water binary mixtures at 298.15 K. • Solubility values were correlated with the Jouyban-Acree model. • Preferential solvation parameters were derived by using the IKBI method. • δx 1,3 values are negative in water-rich mixtures but positive in the other mixtures. - Abstract: Methyl, ethyl and propyl parabens equilibrium solubility was determined in (methanol + water) binary mixtures at 298.15 K. The mole fraction solubility of these compounds increased in 503 (from 2.40 × 10 −4 to 0.121), 1377 (from 9.86 × 10 −5 to 0.136) and 4597 (from 3.73 × 10 −5 to 0.171) times when passing from neat water to neat methanol, for methyl, ethyl and propyl parabens, respectively. All these solubility values were correlated with the Jouyban-Acree model. Preferential solvation parameters by methanol (δx 1,3 ) of these parabens were derived from their thermodynamic solution properties using the inverse Kirkwood-Buff integrals (IKBI) method. For all compounds δx 1,3 values are negative in water-rich mixtures but positive in mixtures with methanol mole fraction greater than 0.32. It is conjecturable that in the former case the hydrophobic hydration around non-polar groups of parabens plays a relevant role in the solvation. Besides, the preferential solvation of these solutes by methanol in mixtures of similar co-solvent compositions and in methanol-rich mixtures could be explained in terms of the higher basic behaviour of methanol.

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

DEFF Research Database (Denmark)

Alberico, E.; Nielsen, Martin

2015-01-01

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...

Le modele de Hubbard bidimensionnel a faible couplage: Thermodynamique et phenomenes critiques

Science.gov (United States)

Roy, Sebastien

Une etude systematique du modele de Hubbard en deux dimensions a faible couplage a l'aide de la theorie Auto-Coherente a Deux Particules (ACDP) dans le diagramme temperature-dopage-interaction-sauts permet de mettre en evidence l'influence des fluctuations magnetiques sur les proprietes thermodynamiques du systeme electronique sur reseau. Le regime classique renormalise a temperature finie pres du dopage nul est marque par la grandeur de la longueur de correlation de spin comparee a la longueur thermique de de Broglie et est caracterisee par un accroissement drastique de la longueur de correlation de spin. Cette croissance exponentielle a dopage nul marque la presence d'un pic de chaleur specifique en fonction de la temperature a basse temperature. Une temperature de crossover est alors associee a la temperature a laquelle la longueur de correlation de spin est egale a la longueur thermique de de Broglie. C'est a cette temperature caracteristique, ou est observee l'ouverture du pseudogap dans le poids spectral, que se situe le maximum du pic de chaleur specifique. La presence de ce pic a des consequences sur l'evolution du potentiel chimique avec le dopage lorsque l'uniformite thermodynamique est respectee. Les contraintes imposees par les lois de la thermodynamique font en sorte que l'evolution du potentiel chimique avec le dopage est non triviale. On demontre entre autres que le potentiel chimique est proportionnel a la double occupation qui est reliee au moment local. Par ailleurs, une derivation de la fonction de mise a l'echelle de la susceptibilite de spin a frequence nulle au voisinage d'un point critique marque sans equivoque la presence d'un point critique quantique en dopage pour une valeur donnee de l'interaction. Ce point critique, associe a une transition de phase magnetique en fonction du dopage a temperature nulle, induit un comportement non trivial sur les proprietes physiques du systeme a temperature finie. L'approche quantitative ACDP permet de

Thermodynamics of the Sorption of Benzimidazoles on Octadecyl Silica Gel from Water-Methanol Eluents

Science.gov (United States)

Shafigulin, R. V.; Bulanova, A. V.

2018-02-01

The standard enthalpy and entropy component of transferring benzimidazoles from water-methanol solutions to surfaces of octadecyl silica gel are determined using reversed-phase high-performance liquid chromatography (RP HPLC). The dependences between the enthalpy and polarizability of the molecules of the studied benzimidazoles, the enthalpy and the entropy factor are studied, and the influence of the quantitative composition of the water-methanol solution on the enthalpy are studied.

Copper Leaching from Copper-ethanolamine Treated Wood: Comparison of Field Test Studies and Laboratory Standard Procedures

OpenAIRE

Nejc Thaler; Miha Humar

2014-01-01

Copper-based compounds are some of the most important biocides for the protection of wood in heavy duty applications. In the past, copper was combined with chromium compounds to reduce copper leaching, but a recent generation of copper-based preservatives uses ethanolamine as a fixative. To elucidate the leaching of copper biocides from wood, Norway spruce (Picea abies) wood was treated with a commercial copper-ethanolamine solution with two different copper concentrations (cCu = 0.125% and 0...

A Four-Site Molecular Model for Simulations of Liquid Methanol and Water-Methanol Mixtures: MeOH-4P.

Science.gov (United States)

Martínez-Jiménez, Manuel; Saint-Martin, Humberto

2018-04-17

In this work, we present a new four-site potential for methanol, MeOH-4P, fitted to reproduce the dielectric constant ε, the surface tension γ s , and the liquid density ρ of the pure liquid at T = 298.15 K and p = 1 bar. The partial charges on each site were taken from the OPLS/2016 model with the only difference of putting the negative charge on the fourth site ( M) instead of on the O atom, as done in four-site water models. The original Lennard-Jones (LJ) parameters of OPLS/2016 for the methyl moiety (Me) were modified for the fitting of ρ and γ s , whereas the parameters of the TIP4P-FB water model were used for the O atom without change. Taking into account the energetic cost of the enhanced dipole relative to the isolated molecule, the results from simulations with this model showed good agreement with experiments for ρ, α p , κ T , C p , and Δ H v- l . Also, the temperature dependence of γ s and ε is satisfactory in the interval between 260 and 360 K, and the critical point description is similar to that of OPLS/2016. It is shown that orientational correlations, described by the Kirkwood factor G k , play a prominent role in the appropriate description of dielectric constants in existing models; unfortunately, the enhancement of the dipole moment produced a low diffusion coefficient D MeOH ; thus, a compromise was required between a good reproduction of ε and an acceptable D MeOH . The use of a fourth site resulted in a significant improvement for water-methanol mixtures described with TIP4P-FB and MeOH-4P, respectively, but required the modification of the LJ geometric combination rule to allow a good description of the methanol molar-fraction dependence of ρ, ε, and methanol (water) diffusion coefficients D MeOH ( D H 2 O ) and excess volume of mixing Δ V mix in the entire range of composition. The resulting free energy of hydration Δ G hyd shows excellent agreement with experiments in the interval between 280 and 360 K.

PdZnAl Catalysts for the Reactions of Water-Gas-Shift, Methanol Steam Reforming, and Reverse-Water-Gas-Shift

Energy Technology Data Exchange (ETDEWEB)

Dagle, Robert A.; Platon, Alexandru; Datye, Abhaya K.; Vohs, John M.; Wang, Yong; Palo, Daniel R.

2008-03-07

Pd/ZnO/Al2O3 catalysts were studied for water-gas-shift (WGS), methanol steam reforming, and reverse-water-gas-shift (RWGS) reactions. WGS activity was found to be dependent on the Pd:Zn ratio with a maximum activity obtained at approximately 0.50, which was comparable to that of a commercial Pt-based catalyst. The catalyst stability was demonstrated for 100 hours time-on-stream at a temperature of 3600C without evidence of metal sintering. WGS reaction rates were approximately 1st order with respect to CO concentration, and kinetic parameters were determined to be Ea = 58.3 kJ mol-1 and k0 = 6.1x107 min-1. During methanol steam reforming, the CO selectivities were observed to be lower than the calculated equilibrium values over a range of temperatures and steam/carbon ratios studied while the reaction rate constants were approximately of the same magnitude for both WGS and methanol steam reforming. These results indicate that although Pd/ZnO/Al2O3 are active WGS catalysts, WGS is not involved in methanol steam reforming. RWGS rate constants are on the order of about 20 times lower than that of methanol steam reforming, suggesting that RWGS reaction could be one of the sources for small amount of CO formation in methanol steam reforming.

Technoeconomic analysis of a methanol plant based on gasification of biomass and electrolysis of water

DEFF Research Database (Denmark)

Clausen, Lasse Røngaard; Houbak, N.; Elmegaard, Brian

2010-01-01

, and the low-temperature waste heat is used for district heat production. This results in high total energy efficiencies (similar to 90%) for the plants. The specific methanol costs for the six plants are in the range 11.8-25.3 (sic)/GJ(exergy). The lowest cost is obtained by a plant using electrolysis......Methanol production process configurations based on renewable energy sources have been designed. The processes were analyzed in the thermodynamic process simulation tool DNA. The syngas used for the catalytic methanol production was produced by gasification of biomass, electrolysis of water, CO2...... with a different syngas production method, were compared. The plants achieve methanol exergy efficiencies of 59-72%, the best from a configuration incorporating autothermal reforming of biogas and electrolysis of water for syngas production. The different processes in the plants are highly heat integrated...

Flow and heat transfer thermohydraulic modelisation during the reflooding phase of a P.W.R.'s core

International Nuclear Information System (INIS)

Raymond, Patrick

1978-04-01

Some generalities about L.O.C.A. are first recalled. The French experimental studies about Emergency Core Cooling System are briefly described. The different heat transfer mechanisms to take into account, according to the flow pattern in the dry zone, and the correlations or methods to calculate them, are defined. Then the Thermohydraulic code computer: FLIRA, which describe the reflooding phase, and a modelisation taking into account the different flow patterns are setted. A first interpretation of ERSEC experiments with a tubular test section shows that it is possible, with this modelisation and some classical heat transfer correlations, to describe the reflooding phase. [fr

Investigating the effects of methanol-water vapor mixture on a PBI-based high temperature PEM fuel cell

DEFF Research Database (Denmark)

Araya, Samuel Simon; Andreasen, Søren Juhl; Nielsen, Heidi Venstrup

2012-01-01

This paper investigates the effects of methanol and water vapor on the performance of a high temperature proton exchange membrane fuel cell (HT-PEMFC). A H3PO4-doped polybenzimidazole (PBI) membrane electrode assembly (MEA), Celtec P2100 of 45 cm2 of active surface area from BASF was employed....... A long-term durability test of around 1250 h was performed, in which the concentrations of methanol-water vapor mixture in the anode feed gas were varied. The fuel cell showed a continuous performance decay in the presence of vapor mixtures of methanol and water of 5% and 8% by volume in anode feed...

Transesterification of triacetin, tributyrin, and soybean oil with methanol over hydrotalcites with different water contents

Energy Technology Data Exchange (ETDEWEB)

Kim, Mi Jin; Park, Se Min; Seo, Gon [School of Applied Chemical Engineering and the Research Institute for Catalysis, Chonnam National University, Yungbong-Dong, Buk-Gu, Gwangju 500-757 (Korea); Chang, Duck Rae [Korea Institute of Industrial Technology, 1110-9 Oryoung-Dong, Buk-Gu, Gwangju 500-480 (Korea)

2010-06-15

Transesterification of triacetin, tributyrin and soybean oil with methanol was examined over rehydrated hydrotalcites (HT-reh), which were previously calcined at 550 C and exposed to an ambient atmosphere, in order to investigate the effect of the water content on their catalytic activity. Rehydration of a calcined hydrotalcite at 25 C produced uniform mesopores of around 4 nm diameter, while the removal of water from the HT-reh by pretreatment at 500 C, formed large heterogeneous mesopores. Methanol was adsorbed and desorbed rapidly in the mesopores of the HT-reh filled with water. The pretreatment of the HT-reh at 500 C removed both water and carbon dioxide, producing strong basic sites. The high activity of fully rehydrated hydrotalcite in the transesterification of three triglycerides was explained by the generation of Broensted basic sites and the rapid migration of methanol in the mesopores, while the improved activity of the rehydrated hydrotalcite pretreated at 500 C by the generation of strong basic sites and empty mesopores due to the removal of water and carbon dioxide. (author)

Ground observations and remote sensing data for integrated modelisation of water budget in the Merguellil catchment, Tunisia

Science.gov (United States)

Mougenot, Bernard

2016-04-01

The Mediterranean region is affected by water scarcity. Some countries as Tunisia reached the limit of 550 m3/year/capita due overexploitation of low water resources for irrigation, domestic uses and industry. A lot of programs aim to evaluate strategies to improve water consumption at regional level. In central Tunisia, on the Merguellil catchment, we develop integrated water resources modelisations based on social investigations, ground observations and remote sensing data. The main objective is to close the water budget at regional level and to estimate irrigation and water pumping to test scenarios with endusers. Our works benefit from French, bilateral and European projects (ANR, MISTRALS/SICMed, FP6, FP7…), GMES/GEOLAND-ESA) and also network projects as JECAM and AERONET, where the Merguellil site is a reference. This site has specific characteristics associating irrigated and rainfed crops mixing cereals, market gardening and orchards and will be proposed as a new environmental observing system connected to the OMERE, TENSIFT and OSR systems respectively in Tunisia, Morocco and France. We show here an original and large set of ground and remote sensing data mainly acquired from 2008 to present to be used for calibration/validation of water budget processes and integrated models for present and scenarios: - Ground data: meteorological stations, water budget at local scale: fluxes tower, soil fluxes, soil and surface temperature, soil moisture, drainage, flow, water level in lakes, aquifer, vegetation parameters on selected fieds/month (LAI, height, biomass, yield), land cover: 3 times/year, bare soil roughness, irrigation and pumping estimations, soil texture. - Remote sensing data: remote sensing products from multi-platform (MODIS, SPOT, LANDSAT, ASTER, PLEIADES, ASAR, COSMO-SkyMed, TerraSAR X…), multi-wavelength (solar, micro-wave and thermal) and multi-resolution (0.5 meters to 1 km). Ground observations are used (1) to calibrate soil

Influence of polyvinylpyrrolidone on the interaction between water and methanol

Directory of Open Access Journals (Sweden)

M. Guettari

2013-09-01

Full Text Available The present work aims to determine the influence of a dissolved polymer, polyvinylpyrrolidone, on the interaction between water and methanol. First, the dynamic viscosities were measured for polymer solutions by a rotational concentric cylinder at 25 ºC and for the polymer concentration range from 0.1 to 0.6 g/dl. The results show a polynomial dependence of the viscosity on polymer concentration. On the hypothesis of a quasi-binary system, a pseudo Grumberg-Nissan constant, d'p, was introduced to quantify the interaction between unlike molecules in the presence of polymer. The interaction between unlike molecules due to the presence of the polymer was quantified by the deviation of the Grumberg-Nissan constant, δd'p= d p. Generally, this constant is negative which means that the interactions between water and methanol decrease in the presence of polyvinylpyrrolidone at 25 ºC. The presence of the polymer induces a perturbation of the dynamic equilibrium between free and complexed molecules

Age dependent accumulation of N-acyl-ethanolamine phospholipids in ischemic rat brain

DEFF Research Database (Denmark)

Moesgaard, B.; Petersen, G.; Hansen, Harald S.

2000-01-01

N-acyl-ethanolamine phospholipids (NAPE) can be formed as a stress response during neuronal injury, and they are precursors for N-acyl- ethanolamines (NAE), some of which are endocannabinoids. The levels of NAPE accumulated during post-decapitative ischemia (6 h at 37°C) were studied in rat brains...... of various age (1, 6, 12, 19, 30, and ~70 days) by the use of P NMR spectroscopy of lipid extracts. This ability to accumulate NAPE was compared with the activity of N-acyltransferase and of NAPE-hydrolyzing phospholipase D (NAPE-PLD) in brain microsomes. These two enzymes are involved in the formation...... brains NAPE accumulation could not be detected (detection limit 0.09 %)]; and 2) this age pattern of accumulation can be explained by a combination of the decreased activity of N- acyltransferase and the increased activity of NAPE-PLD during development. These results point out that it would...

Utilization of Ethanolamine as Carbon Dioxide Absorber For

OpenAIRE

Yusuf, Asdiana Irma; Zakir, Muhammad; Maming, Maming

2015-01-01

Utilization of ethanolamine as carbon dioxide absober for estimating of coral age from langkai island via LSC (Liquid Scintillation Counting) method has been done. Focus is to analyze coral reefs taken from Langkai island surface which is relatively far from the influence of human activities. Chemical preparation was carried out by using a mixture of NaOH with H2O2 30% followed by a mixture of HClO4 with H2O2 30%, and finally with HCl solution to produce a clean sample with 8.6% weight reduct...

Oxo-exchange of gas-phase uranyl, neptunyl, and plutonyl with water and methanol.

Science.gov (United States)

Lucena, Ana F; Odoh, Samuel O; Zhao, Jing; Marçalo, Joaquim; Schreckenbach, Georg; Gibson, John K

2014-02-17

A challenge in actinide chemistry is activation of the strong bonds in the actinyl ions, AnO2(+) and AnO2(2+), where An = U, Np, or Pu. Actinyl activation in oxo-exchange with water in solution is well established, but the exchange mechanisms are unknown. Gas-phase actinyl oxo-exchange is a means to probe these processes in detail for simple systems, which are amenable to computational modeling. Gas-phase exchange reactions of UO2(+), NpO2(+), PuO2(+), and UO2(2+) with water and methanol were studied by experiment and density functional theory (DFT); reported for the first time are experimental results for UO2(2+) and for methanol exchange, as well as exchange rate constants. Key findings are faster exchange of UO2(2+) versus UO2(+) and faster exchange with methanol versus water; faster exchange of UO2(+) versus PuO2(+) was quantified. Computed potential energy profiles (PEPs) are in accord with the observed kinetics, validating the utility of DFT to model these exchange processes. The seemingly enigmatic result of faster exchange for uranyl, which has the strongest oxo-bonds, may reflect reduced covalency in uranyl as compared with plutonyl.

Soil and groundwater remediation guidelines for methanol

International Nuclear Information System (INIS)

2010-12-01

Methanol is used by oil and gas operators to inhibit hydrate formation in the recovery of heavy oils, in natural gas production and transport, as well as in various other production applications. Emissions from methanol primary occur from miscellaneous solvent usage, methanol production, end-product manufacturing, and storage and handling losses. This document provided soil and groundwater remediation guidelines for methanol releases into the environment. The guidelines were consistent with the Alberta Environment tier 1 soil and groundwater framework. The chemical and physical properties of methanol were reviewed. The environmental fate and behavior of methanol releases was discussed, and the behaviour and effects of methanol in terrestrial and aquatic biota were evaluated. The toxicity of methanol and its effects in humans and mammalian species were reviewed. Soil quality and ground water quality guidelines were presented. Surface water and soil guideline calculation methods were provided, and ecological exposure and ground water pathways were discussed. Management limits for methanol concentrations were also provided. 162 refs., 18 tabs., 4 figs.

Dynamics of Water Absorption and Evaporation During Methanol Droplet Combustion in Microgravity

Science.gov (United States)

Hicks, Michael C.; Dietrich, Daniel L.; Nayagam, Vedha; Williams, Forman A.

2012-01-01

The combustion of methanol droplets is profoundly influenced by the absorption and evaporation of water, generated in the gas phase as a part of the combustion products. Initially there is a water-absorption period of combustion during which the latent heat of condensation of water vapor, released into the droplet, enhances its burning rate, whereas later there is a water-evaporation period, during which the water vapor reduces the flame temperature suffciently to extinguish the flame. Recent methanol droplet-combustion experiments in ambient environments diluted with carbon dioxide, conducted in the Combustion Integrated Rack on the International Space Station (ISS), as a part of the FLEX project, provided a method to delineate the water-absorption period from the water-evaporation period using video images of flame intensity. These were obtained using an ultra-violet camera that captures the OH* radical emission at 310 nm wavelength and a color camera that captures visible flame emission. These results are compared with results of ground-based tests in the Zero Gravity Facility at the NASA Glenn Research Center which employed smaller droplets in argon-diluted environments. A simplified theoretical model developed earlier correlates the transition time at which water absorption ends and evaporation starts. The model results are shown to agree reasonably well with experiment.

Effect of water-methanol mixed solvents on the ultrasonic relaxation of cadmium acetate

International Nuclear Information System (INIS)

Sree Rama Murthy, J.; Ramachandra Rao, B.

1976-01-01

Measurements of ultrasonic absorption have been made by pulse technique in 1 M solutions of cadmium acetate with water-methanol mixed solvents. Results are analysed by assuming a single relaxation mechanism. The characteristic frequency of relaxation is found to decrease with increasing composition of methanol in the solvent. It is proposed that the mechanism of relaxation may be perturbation of chemical equilibrium between complex CdAc + ions and Cd ++ , Ac - species by soundwaves. (author)

Ethanol and water adsorption in methanol-derived ZIF-71

KAUST Repository

Lively, Ryan P.; Dose, Michelle E.; Thompson, Joshua A.; McCool, Benjamin A.; Chance, Ronald R.; Koros, William J.

2011-01-01

A room temperature method for synthesizing zeolitic imidizolate framework 71 (ZIF-71) is described. The methanol-based synthesis results in >95% yields (based on Zn) and produces crystals with 70% greater surface area than reported earlier. Ethanol uptake into the ZIF compares favorably with a recent modeling-based study. Water uptake was significantly higher than model predictions. © The Royal Society of Chemistry 2011.

Vapor-liquid equilibria of a minute amount of furfural in water-methanol-ethanol system; Mizu-methanol-ethanol keichu no biryo no furfural no kieki heiko

Energy Technology Data Exchange (ETDEWEB)

Ikari, A.; Hatate, Y.; Uemura, Y. [Kagoshima University, Kagoshima (Japan). Faculty of Engineering

1997-01-10

Vapor-liquid equilibria of a water-methanol-ethanol system containing a minute amount of furfural were measured at atmospheric pressure by use of an Othmer-type still. The experimental results are represented by four triangular diagrams against the liquid compositions of the major components (water, methanol and ethanol), in which three diagrams show the vapor composition of the major components, respectively, and one diagram shows the equilibrium ratio of the trace component (furfural). The curved surface of the equilibrium ratio of the trace component exhibits a gentle downward slope in most areas, but shows a half-saddle face in the neighborhood of the water-ethanol side. 4 refs., 10 figs., 3 tabs.

Anti-inflammatory and cytotoxic effects of methanol, ethanol, and water extracts of Angelicae Dahuricae Radix.

Science.gov (United States)

Wang, Myeong-Hyeon; Jeong, Su-Hyeon; Guo, Huifang; Park, Jun-Beom

2016-01-01

Angelicae Dahuricae Radix has been used for the treatment of headaches, rhinitis, and colds in traditional medicine. Methanol, ethanol, and water extracts of Angelicae Dahuricae Radix were collected. A statistically significant reduction in the cellular viability of the mouse leukemic monocyte macrophage cell line was noted after treatment with water extracts of Angelicae Dahuricae Radix. Stimulation with lipopolysaccharides (LPS) for 24 h led to a robust increase in nitric oxide production, but Angelicae Dahuricae Radix at 400 μg/mL concentration significantly suppressed nitric oxide produced by the LPS-stimulated RAW 264.7 cells in 70% ethanol, absolute ethanol, 70% methanol, absolute methanol, and boiling water groups (P ethanol extract of Angelicae Dahuricae Radix suppressed the LPS-stimulated inducible nitric oxide synthase, interleukin-1β, and cycloxygenase-2 expression. Angelicae Dahuricae Radix showed significant cytotoxic effects on the human adenocarcinoma cell line and keratin-forming cell line. (J Oral Sci 58, 125-131, 2016).

Experimental study and modelisation of a pulse tube refrigerator

International Nuclear Information System (INIS)

Ravex, A.; Rolland, P.; Liang, J.

1992-01-01

A test bench for pulse tube refrigerator characterization has been built. In various configurations (basic pulse tube, orifice pulse tube and double inlet pulse tube), the ultimate temperature and the cooling power have been measured as a function of pressure wave amplitude and frequency for various geometries. A lowest temperature of 28 K has been achieved in a single staged double inlet configuration. A modelisation taking into account wall heat pumping, enthalpy flow and regenerator inefficiency is under development. Preliminary calculation results are compared with experimental data

Measurements and modeling of quaternary (liquid + liquid) equilibria for mixtures of (methanol or ethanol + water + toluene + n-dodecane)

International Nuclear Information System (INIS)

Mohammad Doulabi, F.S.; Mohsen-Nia, M.; Modarress, H.

2006-01-01

The extraction of aromatic compound toluene from alkane, dodecane, by mixed solvents (water + methanol) (water + ethanol) and (methanol + ethanol) have been studied by (liquid + liquid) equilibrium (LLE) measurements at three temperatures (298.15, 303.15, and 313.15) K and ambient pressure. The compositions of liquid phases at equilibrium were determined by gas liquid chromatography. The experimental tie-line data for three quaternary mixtures of {(water + methanol) + toluene + dodecane}, {(water + ethanol) + toluene + dodecane}, and {(methanol + ethanol) + toluene + dodecane} are presented. The experimental quaternary LLE data have been satisfactorily correlated by using the UNIQUAC and NRTL activity coefficient models. The parameters of the models have been evaluated and presented. The tie-line data of the studied quaternary mixtures also were correlated using the Hand method. The partition coefficients and the selectivity factor of solvent are calculated and compared for the three mixed solvents. The comparisons indicate that the selectivity factor for mixed solvent (methanol + ethanol) is higher than the other two mixed solvents at the three studied temperatures. However, considering the temperature variations of partition coefficients of toluene in two liquid phases at equilibrium, an optimum temperature may be obtained for an efficient extraction of toluene from dodecane by the mixed solvents

The effect of electrical conductivity on nanosecond discharges in distilled water and in methanol with argon bubbles

KAUST Repository

Hamdan, Ahmad

2017-03-27

We investigated the effect of a liquid\\'s electrical conductivity (EC) on the physical characteristics of electrical discharges in liquids with gaseous bubbles. Argon gas was supplied into the liquid to form an array of gaseous bubbles in between two electrodes (a pin-to-hollow electrode setup). Methanol and water were considered as base liquids, representing a low and a high dielectric permittivity (ϵ) liquid respectively, while potassium chloride (KCl) was added to control the EC of the liquids. When increasing the EC of the liquids, we found that the discharge probability was reduced by 46% for in-water and 38% for in-methanol discharges. We also found that the injected charge decreased by ∼4 μC as the EC increased. Moreover, as the gap distance increased from 1 to 2.5 mm, the injected charge decreased by 2 μC for in-water discharge and by 4 μC for in-methanol discharge. The plasma emission is another important parameter in characterizing discharges. With increasing the EC, the plasma emission volume decreased linearly by a factor of ∼5. The plasma lifetime was shortened by around 33% for in-water and 20% for in-methanol discharges in the case of d = 1 mm, while the decrease was 40% for in-water and 30% for in-methanol discharges in the case of d = 2.5 mm. Using the broadening characteristics of the Hα line, the electron density was estimated during the first 100 ns by ∼3 × 10 cm for in-water discharges and by ∼2 × 10 cm for in-methanol discharges, and it decreased by about one order of magnitude after 800 ns; note that n dependence on the EC was not significant. The reported findings provide further understanding of electrical discharges in bubbled liquids and highlight the influence of a liquid\\'s EC, which are useful in the development and optimization of the applications based on such process.

Production of synthetic methanol from air and water using controlled thermonuclear reactor power. 2. Capital investment and production costs

Energy Technology Data Exchange (ETDEWEB)

Dang, V D; Steinberg, M [Brookhaven National Lab., Upton, N.Y. (USA)

1977-01-01

Energy requirement and process development of methanol production from air and water using controlled thermonuclear fusion power was discussed in Part 1 (Steinberg et al., Energy conversion;17:97(1977)). This second part presents an economic analysis of the nine processes presented for obtaining carbon dioxide recovery from the atmosphere or the sea for methanol production. It is found that the most economical process of obtaining carbon dioxide is by stripping from sea water. The process of absorption/stripping by dilute potassium carbonate solution is found to be the most economical for the extraction of carbon dioxide from air at atmospheric pressure. The total energy required for methanol synthesis from these sources of carbon dioxide is 3.90 kWh(e)/lb methanol of which 90% is used for generation of hydrogen. The process which consumes the greatest amount of energy is the absorption/stripping of air by water at high pressure and amounts to 13.2 kWh(e)/lb methanol. With nuclear fusion power plants of 1000to 9000 MW(e), it is found that the cost of methanol using the extraction of carbon dioxide from air with dilute potassium carbonate solution is estimated to be in the range between Pound1.73 and Pound2.90/MMB.t.u. (energy equivalent - 1974 cost) for plant capacities of 21 400 to 193 000 bbl/day methanol. This methanol cost is competitive with gasoline in the range of 19 approximately equal to 33c/gallon. For the process of stripping of carbon dioxide from sea water, the cost is found to lie in the range of Pound1.65 to Pound2.71/MMB.t.u. (energy equivalent) for plant capacities of 21 700 to 195 000 bbl/day methanol which is competitive with gasoline in the range of 18 approximately equal to 30 c/gallon. Projection of methanol demand in the year 2020 is presented based on both its conventional use as chemicals and as a liquid fuel substituting for oil and gas.

Utilisation of chlorine-dioxide and peracetic acid as disinfectants of effluents from Bologna waste water treatment plant; Sperimentazione di tecniche di disinfezione mediante biossido di cloro e acido peracetico applicate alle acque reflue dell'impianto di trattamento della citta' di Bologna

Energy Technology Data Exchange (ETDEWEB)

Mancini, M.L. [Bologna Univ., Bologna (Italy). Dipt. di Ingegneria delle Strutture, dei Trasporti, delle Acque, del Rilevamento e del Territorio; Sorrentino, M.

2000-01-01

The necessity to optimize the disinfection phase in the treatment plant of waste water of Bologna made possible an experimental survey about the efficacy of two disinfectant agents utilized: chlorine-dioxide and peracetic acid. Object of the survey is to verify the possibility of utilize, full scale, also peracetic acid as disinfection agent. The experimentation regarded the reals flows adduced and discharged from the plant and it may be an useful reference to verify performance of post-treatment constructed wetlands. Particularly it has been possible to assay the efficacy of the different treatment in waste water with residual concentrations of suspended solids. [Italian] La necessita' di ottimizzare la fase di disinfezione nell'impianto di trattamento acque reflue della citta' di Bologna, sia per il miglioramento delle rese di inattivazione, sia per la riduzione dei costi di esercizio, ha reso necessaria un'indagine sperimentale sull'efficacia di due agenti disinfettanti utilizzati: il biossido di cloro e l'acido peracetico. Scopo dell'indagine e' quello di verificare la possibilita' di impiegare, a scala reale, per il refluo tipico dell'impianto di Bologna, anche l'acido peracetico quale agente di disinfezione. La sperimentazione, condotta ha interessato le portate reali addotte e scaricate dall'impianto e puo' costituire un riferimento utile verificare la fattibilita' igienico-sanitaria di post-trattamenti di lagunaggio o fertirrigazione. In particolare si e' potuta saggiare l'efficacia dei diversi sistemi di trattamento sui reflui aventi concentrazioni residue non trascurabili di solidi sospesi.

The removal of dimethyl phthalate (DMP) from contaminated water by advanced oxidation processes in the presence of methanol

Energy Technology Data Exchange (ETDEWEB)

Al-Tawabini, B.S. [Research Inst., King Fahd Univ. of Petroleum and Minerals, Dhahran (Saudi Arabia)

2003-07-01

A bench-scale laboratory study was conducted to investigate the effect of alcohol (i.e. methanol) presence on the removal efficiency of phthalates from water using Fenton's reagent and UV/H{sub 2}O{sub 2} process. Dimethyl phthalate (DMP) was selected as a target compound. In one batch of experiments, only DMP was spiked into pure water, while in the other batch, DMP was initially dissolved in methanol prior to spiking into water samples. A UV lamp of 100 m Watt emitting at a wavelength of approximately 254 nm was used to provide the radiation. Temperature and pH conditions were kept constant at 25 C and 3, respectively. The results showed that Fenton's reagent was effective in reducing the concentration of DMP in water in the absence of the methanol. More than 90% of DMP was removed within 45 minutes at hydrogen peroxide (H{sub 2}O{sub 2}) and ferrous ion (Fe{sup 2+}) concentrations of 1.0 and 0.4 mM respectively. However, Fenton's reagent failed to do so in the presence of methanol. On the other hand, results showed that UV/H{sub 2}O{sub 2} system was effective in removing DMP from both pure, as well as methanol-spiked water. The results clearly indicated that UV radiation plays a fundamental role in the degradation of the target compound. (orig.)

Compact Fuel-Cell System Would Consume Neat Methanol

Science.gov (United States)

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.

A Masing Event in NGC 6334I: Contemporaneous Flaring of Hydroxyl, Methanol and Water Masers

Science.gov (United States)

MacLeod, G. C.; Smits, D. P.; Goedhart, S.; Hunter, T. R.; Brogan, C. L.; Chibueze, J. O.; van den Heever, S. P.; Thesner, C. J.; Banda, P. J.; Paulsen, J. D.

2018-04-01

As a product of the maser monitoring program with the 26 m telescope of the Hartebeesthoek Radio Astronomy Observatory (HartRAO), we present an unprecedented, contemporaneous flaring event of 10 maser transitions in hydroxyl, methanol, and water that began in 2015 January in the massive star-forming region NGC 6334I in the velocity range -10 to -2 km s-1. The 6.7 GHz methanol and 22.2 GHz water masers began flaring within 22 days of each other, while the 12.2 GHz methanol and 1665 MHz hydroxyl masers flared 80 and 113 days later respectively. The 1665 MHz, 6.7 GHz, and 22.2 GHz masers have all remained in their flared state for nearly 3 years. The brightest flaring components increased by factors of 66, 21, 26, and 20 in the 12.2 and 6.7 GHz methanol, 1665 MHz hydroxyl and 22.2 GHz water maser transitions respectively; some weaker components increased by up to a factor of 145. We also report new maser emission in the 1720, 6031, and 6035 MHz OH lines and the 23.1 GHz methanol line, along with the detection of only the fifth 4660 MHz OH maser. We note the correlation of this event with the extraordinary (sub)millimeter continuum outburst from the massive protostellar system NGC 6334I-MM1 and discuss the implications of the observed time lags between different maser velocity components on the nature of the outburst. Finally, we identify two earlier epoch maser flaring events likely associated with this object, which suggest a recurring accretive phenomenon that generates powerful radiative outbursts.

Effect of methanol on the liquefaction reaction of biomass in hot compressed water under microwave energy

Science.gov (United States)

Junming Xu; Jianchun Jiang; Chun-Yun Hse; Todd F. Shupe

2013-01-01

Liquefaction of sawdust was studied in methanol-water solutions using an acid catalyst under microwave energy. The effect of the methanol concentration on the changes of components in the liquefied products was analyzed by gas chromatography−mass spectrometry (GC−MS). It was found that 5-hydroxymethylfurfural (HMF) and levulinic acid are the...

Comparison of the thermal decomposition processes of several aminoalcohol-based ZnO inks with one containing ethanolamine

Energy Technology Data Exchange (ETDEWEB)

Gómez-Núñez, Alberto [University of Barcelona, Department of Electronics, Martí i Franquès 1, E08028-Barcelona (Spain); Roura, Pere [University of Girona, Department of Physics, Campus Montilivi, Edif. PII, E17071-Girona, Catalonia (Spain); López, Concepción [University of Barcelona, Department of Inorganic Chemistry, Martí i Franquès 1, E08028-Barcelona (Spain); Vilà, Anna, E-mail: avila@el.ub.edu [University of Barcelona, Department of Electronics, Martí i Franquès 1, E08028-Barcelona (Spain)

2016-09-15

Highlights: • Four alternatives to ethanolamine as stabilizer for the chemical synthesis of ZnO with zinc acetate dihydrate are proposed: aminopropanol, aminomethyl butanol, aminophenol and aminobenzyl alcohol. • Thermal decomposition processes described. Nitrogen cyclic compounds result. • Molecule flexibility helps decomposition, and in particular aliphatic aminoalcohols (quite flexible) decompose the precursor at lower temperatures than aromatic ones (more rigid). • Aminopropanol, aminomethyl butanol and aminobenzyl crystallize ZnO at a lower temperature than ethanolamine. • Nitrogen cyclic specimens have been identified and evolve in all cases (included ethanolamine) at temperatures up to 600 °C. - Abstract: Four inks for the production of ZnO semiconducting films have been prepared with zinc acetate dihydrate as precursor salt and one among the following aminoalcohols: aminopropanol (APr), aminomethyl butanol (AMB), aminophenol (APh) and aminobenzyl alcohol (AB) as stabilizing agent. Their thermal decomposition process has been analyzed in situ by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and evolved gas analysis (EGA), whereas the solid product has been analysed ex-situ by X-ray diffraction (XRD) and infrared spectroscopy (IR). Although, except for the APh ink, crystalline ZnO is already obtained at 300 °C, the films contain an organic residue that evolves at higher temperature in the form of a large variety of nitrogen-containing cyclic compounds. The results indicate that APr can be a better stabilizing agent than ethanolamine (EA). It gives larger ZnO crystal sizes with similar carbon content. However, a common drawback of all the amino stabilizers (EA included) is that nitrogen atoms have not been completely removed from the ZnO film at the highest temperature of our experiments (600 °C).

Thermal tests on UF6 containers and valves modelisation and extrapolation on real fire situations

International Nuclear Information System (INIS)

Duret, B.; Warniez, P.

1988-12-01

From realistic tests on containers or on valves, we propose a modelisation which we apply to 3 particular problems: resistance of a 48 Y containers, during a fire situation. Influence of the presence of a valve. Evaluation of a leakage through a breach, mechanically created before a fire

Use of controlled thermonuclear reactor fusion power for the production of synthetic methanol fuel from air and water

International Nuclear Information System (INIS)

Steinberg, M.; Vi Duong Dang.

1975-04-01

Methanol synthesis from carbon dioxide, water and nuclear fusion energy is extensively investigated. The entire system is analyzed from the point of view of process design and economic evaluation of various processes. The main potential advantage of a fusion reactor (CTR) for this purpose is that it provides a large source of low cost environmentally acceptable electric power based on an abundant fuel source. Carbon dioxide is obtained by extraction from the atomsphere or from sea water. Hydrogen is obtained by electrolysis of water. Methanol is synthesized by the catalytic reaction of carbon dioxide and hydrogen. The water electrolysis and methanol synthesis units are considered to be technically and commercially available. The benefit of using air or sea water as a source of carbon dioxide is to provide an essentially unlimited renewable and environmentally acceptabe source of hydrocarbon fuel. Extraction of carbon dioxide from the atmosphere also allows a high degree of freedom in plant siting. (U.S.)

NMR and Electrochemical Investigation of the Transport Properties of Methanol and Water in Nafion and Clay-Nanocomposites Membranes for DMFCs

Directory of Open Access Journals (Sweden)

Vincenzo Baglio

2012-06-01

Full Text Available Water and methanol transport behavior, solvents adsorption and electrochemical properties of filler-free Nafion and nanocomposites based on two smectite clays, were investigated using impedance spectroscopy, DMFC tests and NMR methods, including spin-lattice relaxation and pulsed-gradient spin-echo (PGSE diffusion under variable temperature conditions. Synthetic (Laponite and natural (Swy-2 smectite clays, with different structural and physical parameters, were incorporated into the Nafion for the creation of exfoliated nanocomposites. Transport mechanism of water and methanol appears to be influenced from the dimensions of the dispersed platelike silicate layers as well as from their cation exchange capacity (CEC. The details of the NMR results and the effect of the methanol solution concentration are discussed. Clays particles, and in particular Swy-2, demonstrate to be a potential physical barrier for methanol cross-over, reducing the methanol diffusion with an evident blocking effect yet nevertheless ensuring a high water mobility up to 130 °C and for several hours, proving the exceptional water retention property of these materials and their possible use in the DMFCs applications. Electrochemical behavior is investigated by cell resistance and polarization measurements. From these analyses it is derived that the addition of clay materials to recast Nafion decreases the ohmic losses at high temperatures extending in this way the operating range of a direct methanol fuel cell.

Reuse of treated waste water for the irrigation of ornamental plants. The case of Pistoia; Riuso di acque reflue depurate di specie ornamentali: l'impianto pilota di Pistoia

Energy Technology Data Exchange (ETDEWEB)

Gori, R.; Lubello, C. [Florence Univ., Florence (Italy). Dipt. di Ingegneria Civile

1999-12-01

After a brief introduction on irrigation waste water reuse, the paper deals with the case of Pistoia (italy), the most important nursery area in Italy, which has developed an experiment for evaluating the effects of waste water treatment plant effluent irrigation. The better physiological and growth parameters of plants irrigated with the effluent shows that it could be a valid alternative of water and fertilizer nutrients resources for ornamental plants. [Italian] Dopo una breve introduzione sul riuso delle acque reflue a fini irrigui, il lavoro affronta il caso di Pistoia, sede della maggiore area vivaistica italiana, che utilizza le acque reflue dal 1998 con una sperimentazione volta a verificare gli effetti dell'irrigazione con l'effluente dell'impianto di depurazione centrale. Le piante cosi' irrigate hanno mostrato parametri di crescita e fisiologici generalmente migliori di quelli riscontrati sulle piante irrigate con i metodi tradizionali.

Variation of the solvation number of Eu(III) in mixed system of methanol and water

International Nuclear Information System (INIS)

Suganuma, H.; Arisaka, M.; Omori, T.; Satoh, I.; Choppin, G.R.

1999-01-01

The stability constants (β 1 ) of the monofluoride complex of Eu(III) have been determined in mixed solvents of methanol and water at a 0.10 M ionic strength using a solvent extraction technique. The values of ln β 1 increase as the mole fraction of methanol in the mixed solvent system increases. The variation in the stability constants can be correlated with both the large effect due to the solvation of F and the small effect due to both (1) the solvation of cations in connection with complexation and (2) the electrostatic attraction between Eu 3+ and F - . Based on the variation in the sum of (1) and (2) in water and the mixed solvent solutions, it was determined that the coordination number (CN) of Eu(III) varied from a mixture of CN = 9 and 8 to CN = 8 at about a 0.03 mole fraction of methanol in the mixed solvent. (orig.)

Modelling and experimental studies on a direct methanol fuel cell working under low methanol crossover and high methanol concentrations

Energy Technology Data Exchange (ETDEWEB)

Oliveira, V.B.; Pinto, A.M.F.R. [Centro de Estudos de Fenomenos de Transporte, Departamento de Eng. Quimica, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); Rangel, C.M. [Instituto Nacional de Energia e Geologia, Fuel Cells and Hydrogen, Estrada do Paco do Lumiar, 1649-038 Lisboa (Portugal)

2009-08-15

A number of issues need to be resolved before DMFC can be commercially viable such as the methanol crossover and water crossover which must be minimised in portable DMFCs. The main gain of this work is to systematically vary commercial MEA materials and check their influence on the cell performance of a direct methanol fuel cell operating at close to room temperature. A detailed experimental study on the performance of an <> developed DMFC with 25 cm{sup 2} of active membrane area, working near the ambient conditions is described. Tailored MEAs (membrane-electrode assemblies), with different structures and combinations of gas diffusion layers (GDLs), were designed and tested in order to select optimal working conditions at high methanol concentration levels without sacrificing performance. The experimental polarization and power density curves were successfully compared with the predictions of a steady state, one-dimensional model accounting for coupled heat and mass transfer, along with the electrochemical reactions occurring in the DMFC recently developed by the same authors. The influence of the anode gas diffusion layer media, the membrane thickness and the MEA properties on the cell performance are explained under the light of the predicted methanol crossover rate across the membrane. A tailored MEA build-up with the common available commercial materials was proposed to achieve relatively low methanol crossover, operating at high methanol concentrations. The use of adequate materials for the gas diffusion layers (carbon paper at the anode GDL and carbon cloth at the cathode GDL) enables the use of thinner membranes enhancing the water back diffusion which is essential to work at high methanol concentrations. (author)

Experimental Validation of Methanol Crossover in a Three-dimensional, Two-Fluid Model of a Direct Methanol Fuel Cell

DEFF Research Database (Denmark)

Olesen, Anders Christian; Berning, Torsten; Kær, Søren Knudsen

2012-01-01

A fully coupled three-dimensional, steady-state, two-fluid, multi-component and non-isothermal DMFC model has been developed in the commercial CFD package CFX 13 (ANSYS inc.). It accounts for the presence of micro porous layers, non-equilibrium phase change, and methanol and water uptake...... in the ionomer phase of the catalytic layer, and detailed membrane transport of methanol and water. In order to verify the models ability to predict methanol crossover, simulation results are compared with experimental measurements under different current densities along with air and methanol stoichiometries....... Methanol crossover is indirectly measured based on the combined anode and cathode exhaust CO2 mole fraction and by accounting for the CO2 production at the anode as a function of current density. This approach is simple and assumes that all crossed over methanol is oxidized. Moreover, it takes CO2...

Adsorption of methanol, ethanol and water on well-characterized PtSn surface alloys

Science.gov (United States)

Panja, Chameli; Saliba, Najat; Koel, Bruce E.

1998-01-01

Adsorption and desorption of methanol (CH 3OH), ethanol (C 2H 5OH) and water on Pt(111) and two, ordered, PtSn alloys has been studied primarily using temperature-programmed desorption (TPD) mass spectroscopy. The two alloys studied were the {p(2 × 2) Sn}/{Pt(111) } and (√3 × √3) R30° {Sn}/{Pt(111) } surface alloys prepared by vapor deposition of Sn on Pt(111), with θSn = 0.25 and 0.33, respectively. All three molecules are weakly bonded and reversibly adsorbed under UHV conditions on all three surfaces, molecularly desorbing during TPD without any decomposition. The two PtSn surface alloys were found to chemisorb both methanol and ethanol slightly more weakly than on the Pt(111) surface. The desorption activation energies measured by TPD, and hence the adsorption energies, of both methanol and ethanol progressively decrease as the surface concentration of Sn increases, compared with Pt(111). The decreased binding energy leads one to expect a lower reactivity for these alcohols on the two alloys. The sticking coefficients and the monolayer coverages of these alcohols on the two alloys were identical to that on Pt(111) at 100 K, independent of the amount of Sn present in the surface layer. Alloying Sn in Pt(111) also slightly weakens the adsorption energy of water. Water clusters are formed even at low coverages on all three surfaces, eventually forming a water bilayer prior to the formation of a condensed ice phase. These results are relevant to a molecular-level explanation for the reactivity of Sn-promoted Pt surfaces that have been used in the electro-oxidation of simple organic molecules.

The influence of water on the oxygen-silver interaction and on the oxidative dehydrogenation of methanol

NARCIS (Netherlands)

Lefferts, Leon; Van Ommen, Jan G.; Ross, Julian R H

1988-01-01

Experiments carried out using temperature-programmed desorption and reduction could detect no interaction between water and silver at 200 °C. However, separate experiments on the effect of water on the oxidative dehydrogenation of methanol over a silver catalyst showed that water affected the

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

Science.gov (United States)

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

2014-02-01

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

The Methanol Economy Project

Energy Technology Data Exchange (ETDEWEB)

Olah, George [Univ. of Southern California, Los Angeles, CA (United States); Prakash, G. K. [Univ. of Southern California, Los Angeles, CA (United States)

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.

Multiphase Production. Representation of Thermodynamic Properties of Methanol by Different Equations of State Production polyphasique. Représentation des propriétés thermodynamiques du méthanol à partir de différentes équations d'état

Directory of Open Access Journals (Sweden)

Peneloux A.

2006-11-01

Full Text Available For oil and gas offshore production, any extension of the Multiphase Production Concept to more complex effluents under more difficult transport conditions, requests a better understanding and control of :(a the thermodynamic behaviour of water-hydrocarbon mixtures,(b the efficiency of various additives (or mixtures of additives, necessary for a safe, reliable and economical operation of the production and transport facilities. One of the main additives used for hydrate control being methanol, this paper deals specifically with its thermodynamic properties and includes:(a first, an exhaustive bibliography of experimental-data with the method used for the selection of a coherent and reliable data base,(b then, a comparison of the results obtained, after adjustement on the data base :- with various cubic and not-cubic equations of state : Peng-Robinson, Cubic-Chain-Of-Rotators (CCOR, Chain-Of-Rotators (COR,- as well as with equations of state including methanol association phenomena (Anderko model, Wenzel and Krop model,(c and finally, an empirical Bipolynomial equation of state which represents the methanol thermodynamic properties with a good accuracy. Pour la production d'hydrocarbures en mer, le concept de transport polyphasique sur longues distances des fluides de réservoir non traités sur le champ est appelé à se développer. Les raisons du succès de ce concept sont évidentes : - sécurité des personnes : strict minimum de personnel travaillant en mer, minimum de trajets par hélicoptères, minimum de trafic maritime ; - protection de l'environnement : aucun rejet d'hydrocarbures ni à l'atmosphère, ni à la mer; - coûts réduits pour le développement comme pour l'exploitation : minimum d'équipement en mer (têtes de puits, vannes multivoies, débitmètres triphasiques,. . . , d'où des coûts réduits de 30 à 50 % pour des champs marginaux qui pourraient rester commercialement inexploitables avec des schémas de d

Cold sprayed WO3 and TiO2 electrodes for photoelectrochemical water and methanol oxidation in renewable energy applications.

Science.gov (United States)

Haisch, Christoph; Schneider, Jenny; Fleisch, Manuel; Gutzmann, Henning; Klassen, Thomas; Bahnemann, Detlef W

2017-10-03

Films prepared by cold spray have potential applications as photoanodes in electrochemical water splitting and waste water purification. In the present study cold sprayed photoelectrodes produced with WO 3 (active under visible light illumination) and TiO 2 (active under UV illumination) on titanium metal substrates were investigated as photoanodes for the oxidation of water and methanol, respectively. Methanol was chosen as organic model pollutant in acidic electrolytes. Main advantages of the cold sprayed photoelectrodes are the improved metal-semiconductor junctions and the superior mechanical stability. Additionally, the cold spray method can be utilized as a large-scale electrode fabrication technique for photoelectrochemical applications. Incident photon to current efficiencies reveal that cold sprayed TiO 2 /WO 3 photoanodes exhibit the best photoelectrochemical properties with regard to the water and methanol oxidation reactions in comparison with the benchmark photocatalyst Aeroxide TiO 2 P25 due to more efficient harvesting of the total solar light irradiation related to their smaller band gap energies.

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

Science.gov (United States)

Feng, Yan; Liu, Hui; Yang, Jun

2017-06-01

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

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

Science.gov (United States)

Feng, Yan; Liu, Hui; Yang, Jun

2017-01-01

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

Study on the conditions of methanol use as a secondary refrigerant; Etude sur les conditions d'utilisation du methanol comme refrigerant secondaire

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-11-01

This study examined the advantages and safe use of a water and methanol solution for use in a piped cooling network in skating rinks. A methanol/water solution offers simple repair solutions for leaks under ice, because unlike brine, it does not leave spots or soften the ice. The solution is less corrosive than brine and offers efficient heat transfer in heat exchangers. The standards and regulations that apply to the methanol/water solution were outlined. The following preventive measures are recommended to minimize risk associated with methanol in skating rinks: solutions should be diluted to 25 per cent methanol to avoid storing and handling of more concentrated products; methanol vapour detectors should be installed in service rooms where spills may occur; respiratory and protective eye protection should be available in service rooms; and, protection should be provided against freezing when the product is circulated outside of the arena. This study also examined the negative effects on health, including toxicity. Risks related to the environment, flammability and the physicochemical compatibility of methanol with materials were examined. The properties of the methanol/water solution were listed with reference to flash point, autoignition temperature, and the lower and upper flammable or explosive limits. tabs., figs. appendices.

Probing Reversible Chemistry in Coenzyme B12-Dependent Ethanolamine Ammonia Lyase with Kinetic Isotope Effects

Science.gov (United States)

Jones, Alex R; Rentergent, Julius; Scrutton, Nigel S; Hay, Sam

2015-01-01

Coenzyme B12-dependent enzymes such as ethanolamine ammonia lyase have remarkable catalytic power and some unique properties that enable detailed analysis of the reaction chemistry and associated dynamics. By selectively deuterating the substrate (ethanolamine) and/or the β-carbon of the 5′-deoxyadenosyl moiety of the intrinsic coenzyme B12, it was possible to experimentally probe both the forward and reverse hydrogen atom transfers between the 5′-deoxyadenosyl radical and substrate during single-turnover stopped-flow measurements. These data are interpreted within the context of a kinetic model where the 5′-deoxyadenosyl radical intermediate may be quasi-stable and rearrangement of the substrate radical is essentially irreversible. Global fitting of these data allows estimation of the intrinsic rate constants associated with CoC homolysis and initial H-abstraction steps. In contrast to previous stopped-flow studies, the apparent kinetic isotope effects are found to be relatively small. PMID:25950663

Identification of marine methanol-utilizing bacteria

Energy Technology Data Exchange (ETDEWEB)

Yamamoto, M; Iwaki, H; Kouno, K; Inui, T

1980-01-01

A taxonomical study of 65 marine methanol-utilizing bacteria is described. They were Gram-negative, non-spore-forming rods with a polar flagellum and had marine bacterial properties and required vitamin B/sub 12/ for growth. All of them assimilated fructose in addition to C/sub 1/-compounds and produced acid oxidatively from fructose. Twenty-four strains assimilated only C/sub 1/-compounds. They were resistant to penicillin, oxytetracycline and 0/129 substance (Vibrio stat), and tolerant to 12% NaCl. Guanine-cytosine contents of deoxyribonucleic acid in typical strains fell in the range of 43.8 to 47.6%. Other morphological and physiological properties were almost the same as those of terrestrial methanol-utilizers. Bacteria in the first group (41 strains) were facultative methylotrophs and were divided into three subgroups by the assimilation of methylated amines, that is, subgroup I (30 strains) assimilated mono-, di- and tri-methylamine, subgroup II (9 strains) assimilated only mono-methylamine, the bacteria of subgroups I and II were named Alteromonas thalassomethanolica sp. nov. and subgroup III (2 strains) did not assimilate methylated amines, and was tentatively assigned as Alteromonas sp. The second group of bacteria (24 strains) was obligate methylotrophs, named Methylomonas thalassica sp. nov. and was divided into subgroup IV (15 strains) which assimilated mono-, di and tri-methylamine and subgroup V (9 strains) which assimilated mono-methylamine.

Brain uptake and metabolism of the endocannabinoid anandamide labeled in either the arachidonoyl or ethanolamine moiety

International Nuclear Information System (INIS)

Hu, Kun; Sonti, Shilpa; Glaser, Sherrye T.; Duclos, Richard I.; Gatley, Samuel J.

2017-01-01

Introduction: Anandamide (N-arachidonoylethanolamine) is a retrograde neuromodulator that activates cannabinoid receptors. The concentration of anandamide in the brain is controlled by fatty acid amide hydrolase (FAAH), which has been the focus of recent drug discovery efforts. Previous studies in C57BL/6 mice using [ 3 H-arachidonoyl]anandamide demonstrated deposition of tritium in thalamus and cortical areas that was blocked by treatment with an FAAH inhibitor and that was not seen in FAAH-knockout mice. This suggested that long chain fatty acid amides radiolabeled in the fatty acid moiety might be useful as ex vivo and in vivo radiotracers for FAAH, since labeled fatty acid released by hydrolysis would be rapidly incorporated into phospholipids with long metabolic turnover periods. Methods: Radiotracers were administered intravenously to conscious Swiss–Webster mice, and radioactivity concentrations in brain areas was quantified and radiolabeled metabolites determined by radiochromatography. Results: [ 14 C]Arachidonic acid, [ 14 C-arachidonoyl]anandamide and [ 14 C-ethanolamine]anandamide, and also [ 14 C]myristic acid, [ 14 C-myristoyl]myristoylethanolamine and [ 14 C-ethanolamine]myristoyl-ethanolamine all had very similar distribution patterns, with whole brain radioactivity concentrations of 2–4% injected dose per gram. Pretreatment with the potent selective FAAH inhibitor URB597 did not significantly alter distribution patterns although radiochromatography demonstrated that the rate of incorporation of label from [ 14 C]anandamide into phospholipids was decreased. Pretreatment with the muscarinic agonist arecoline which increases cerebral perfusion increased brain uptake of radiolabel from [ 14 C]arachidonic acid and [ 14 C-ethanolamine]anandamide, and (in dual isotope studies) from the unrelated tracer [ 125 I]RTI-55. Conclusions: Together with our previously published study with [ 18 F-palmitoyl]16-fluoro-palmitoylethanolamine, the data show that the

Population dynamics of toxic phytoplankton and bacterial flora in the waters of the low Adriatic sea; Dinamica di popolazione di fitoplancton tossico e flora batterica nel basso Adriatico

Energy Technology Data Exchange (ETDEWEB)

Caroppo, C.; Stabili, L.; Cavallo, R.A.; Pastore, M. [CNR, Ist. Sperimentale Talassografico Attlio Cerruti, Taranto (Italy); Marchiori, E. [Rome Univ., Rome (Italy). Dipt. di Chimica Organica; Bruno, M. [Istituto Superiore di Sanita' , Laboratorio di Igiene Ambientale, Rome (Italy)

2000-07-01

The coastal areas of the Southern Adriatic Sea, in particular the Apulian ones, may be considered an example of intact ecosystem and represent an ideal term of comparison to other marine ecosystems having higher levels of pollution (Northern Adriatic Sea). In order to evaluate the sanitary levels of this environment, four transect were investigated during two years monitoring (April 1995-March 1997) along the Otranto Channel coasts, by joint research groups of the Environmental Hygiene Laboratory of the Istituto Superiore di Sanita' and the Istituto Sperimentale Talassografico A. Cerruti of CNR in Taranto. The study underlines the phytoplanktic and bacterial population dynamics, and the detection of the microbiological water quality along the coast tract Brindisi-Lecce-Otranto-S. Maria di Leuca. The results acquired pointed out population dynamics of some potantially toxic species of Dinophysis genus and Pseudo-nitzschia delicatissima. These depended on the winter nutrient loads due to the ASW (Adriatic Superficial Waters) and to the LIW (Levantine Intermediate Waters). The bacterial community was mainly constituted by genera Aeromonas, Photobacterium, Cytophaga and Pseudomonas. Also the presence of Enterobacteriaceae family was relevant. Among the pathogenic vibrios the most frequently isolated species were Vibrio alginolyticus and Vibrio vulnificus. [Italian] Considerando che le zone del basso Adriatico, in particolare quelle pugliesi, costituiscono un biotopo ancora relativamente inalterato, esse sono state oggetto di un'indagine sperimentale condotta in 24 mesi di attivita' (aprile 1995-marzo 1997) lungo le coste del Canale di Otranto, ad opera di un gruppo congiunto del Laboratorio di Igiene Ambientale dell'Istituto Superiore di Sanita' e dei laboratori dell'Istituto Sperimentale Talassografico A. Cerruti del CNR di Taranto, ai fini di valutare lo stato di salute di questo ambiente, che fornisce, con buona probabilita', un

Diverses questions de mecanique et de thermodynamique classiques et relativistes

Science.gov (United States)

de Broglie, Louis; Lochak, Georges; Karatchentzeff, Michel; Fargue, Daniel

Ce livre reproduit un cours inédit de Louis de Broglie, de 1948, dans lequel il réexamine, gráce à la relativité, les analogies entre la mécanique et la thermodynamique étudiés par Helmholtz, Boltzmann et Planck avant le succès de la mécanique statistique. C'est le premier d'une série de travaux de de Broglie en vue de prolonger sa découverte de 1924 vers une mécanique ondulatoire des processus irréversibles, en unifiant les principes de Fermat, de Maupertuis et de Carnot-Clausius. L'intérêt du livre est triple: 1. une généralisation de la mécanique quantique qui décrirait les transitions quantiques en tant que processus dynamiques; 2. revisiter la physique classique en compagnie de l'un des plus grands physiciens du siècle 3. découvrir quelques grands idées oubliées de la physique classique.

Conductivity Measurements of Alkali Metal Thiocyanates in Water-Methanol Mixtures; Mizu-metanoru kongoyoubai ni okeru arukari kinzoku chioshiansan`en no denki dendodo sokutei

Energy Technology Data Exchange (ETDEWEB)

Kubota, Eiji.; Horimoto, Sanaki. [Shinshu University, Nagano (Japan). Faculty of Science

1999-03-10

The counductivity of several alkali nmetal thiocyanates in water-methanol mixtures was measured at 25degreeC. the data were analyzed using Lee-Wheaton theory for symmetrical electroyers to cbtain ion association constant, K{sub A}, limiting molar sonductivity, {Lambda}{sub 0}, and limiting ionic molar conductivity, lamnda{sub 0}{+-}. In all the solvent systems, calculated{lambda}{sub 0}{sup +} values of the alkali metal ions increase in the order L{sub i}{sup +}methanol was ca.0.4. The changes in {lambda}{sub 0}{+-} of these alkali metal ions and thiocyanate ion with the molar fraction of methanol agree with change in the viscosity of the solvent or the heat of mixing of wateer-methanol mixtures. These alkali metal thiocyanates from little or no ion aggregated in water and water-methanol mixtures. These alkali metal thiocyanates K{sub A}=15-24 dm{sup 3} mol{sub -1} in methanol. (author)

Carbon nanotubes based methanol sensor for fuel cells application.

Science.gov (United States)

Kim, D W; Lee, J S; Lee, G S; Overzet, L; Kozlov, M; Aliev, A E; Park, Y W; Yang, D J

2006-11-01

An electrochemical sensor is built using vertically grown multi-walled carbon nanotubes (MWNTs) micro-array to detect methanol concentration in water. This study is done for the potential use of the array as methanol sensor for portable units of direct methanol fuel cells (DMFCs). Platinum (Pt) nanoparticles electro-deposited CNTs (Pt/CNTs) electrode shows high sensitivity in the measurement of methanol concentration in water with cyclic voltammetry (CV) measurement at room temperature. Further investigation has also been undertaken to measure the concentration by changing the amount of the mixture of methanol and formic acid in water. We compared the performance of our micro array sensor built with Pt/CNTs electrodes versus that of Pt wire electrode using CV measurement. We found that our Pt/CNTs array sensor shows high sensitivity and detects methanol concentrations in the range of 0.04 M to 0.10 M. In addition, we found that co-use of formic acid as electrolyte enables us to measure up to 1.0 M methanol concentration.

Distribution of MEG and methanol in well-defined hydrocarbon and water systems: Experimental measurement and modeling using the CPA EoS

DEFF Research Database (Denmark)

Riaz, Muhammad; Yussuf, Mustafe A.; Kontogeorgis, Georgios

2013-01-01

+ water. These data are satisfactorily correlated (binaries) and predicted (ternaries) using Cubic Plus Association (CPA) equation of state (EoS). CPA is also applied to binary LLE of aromatic hydrocarbon + water and VLE of methane + methanol. Finally the distribution of water and inhibitors (methanol...... and MEG) in various phases is modeled using CPA. The hydrocarbon phase consists of mixture-1 (methane, ethane, n-butane) or mixture-2 (methane, ethane, propane, n-butane, n-heptane, toluene and n-decane). CPA can satisfactorily predict the water content in the gas phase of the multicomponent systems...

Study on fuel supplying method and methanol concentration sensor for the high efficient operation of methanol fuel cells. Methanol nenryo denchi no unten ni okeru nenryo kyokyu hoho no kento to methanol nodo sensor no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Tsukui, Tsutomu; Doi, Ryota; Yasukawa, Saburo; Kuroda, Osamu [Hirachi, Ltd., Tokyo, (Japan)

1990-01-20

A fuel supplying method was studied and demonstrated, essential to the high efficient operation of methanol fuel cells. Methanol and water were supplied independently from each tank to an anordic electrolyte tank in a circulating system, detecting a methanol concentration and liquid level of anordic electrolyte by each sensor, respectively. A methanol sensor was also developed to detect accurately the concentration based on electrochemical reaction under a constant voltage. A detection control circuit was insulated from a constant-voltage power supply to prevent external noises. The methanol sensor output was compensated for temperature, and a new level sensing method was adopted to send out a command comparing different responses to electrolyte shortage. As the methanol fuel cell was operated with this fuel supplying system, the stable characteristics of the cell were obtained within the variation of {plus minus} 0.1mol/l from the specified methanol concentration. 6 refs., 17 figs., 1 tab.

Steps on rutile TiO2(110): Active sites for water and methanol dissociation

DEFF Research Database (Denmark)

Martinez, Umberto; Vilhelmsen, Lasse; Kristoffersen, Henrik Høgh

2011-01-01

for each step edge, more stable, reconstructed structures were found for the step edge, while the bulk truncated structures were recovered for the step edge.We demonstrate how oxygen vacancies along these defects have lower formation energies than on flat terraces and how water and methanol...

Photocatalytic conversion of methane to methanol

Energy Technology Data Exchange (ETDEWEB)

Taylor, C.E.; Noceti, R.P.; D`Este, J.R. [Pittsburgh Energy Technology Center, PA (United States)

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.

Oxidation of hazardous waste in supercritical water: A comparison of modeling and experimental results for methanol destruction

International Nuclear Information System (INIS)

Butler, P.B.; Bergan, N.E.; Bramlette, T.T.; Pitz, W.J.; Westbrook, C.K.

1991-01-01

Recent experiments at Sandia National Laboratories conducted in conjunction with MODEC Corporation have demonstrated successful clean- up of contaminated water in a supercritical water reactor. These experiments targeted wastes of interest to Department of Energy production facilities. In this paper we present modeling and experimental results for a surrogate waste containing 98% water, 2% methanol, and parts per million of chlorinated hydrocarbons and laser dyes. Our initial modeling results consider only methanol and water. Experimental data are available for inlet and outlet conditions and axial temperature profiles along the outside reactor wall. The purpose of our model is to study the chemical and physical processes inside the reactor. We are particularly interested in the parameters that control the location of the reaction zone. The laboratory-scale reactor operates at 25 MPa., between 300 K and 900 K; it is modeled as a plug-flow reactor with a specified temperature profile. We use Chemkin Real-Gas to calculate mixture density, with the Peng-Robinson equation of state. The elementary reaction set for methanol oxidation and reactions of other C 1 and C 2 hydrocarbons is based on previous models for gas-phase kinetics. Results from our calculations show that the methanol is 99.9% destroyed at 1/3 the total reactor length. Although we were not able to measure composition of the fluid inside the experimental reactor, this prediction occurs near the location of the highest reactor temperature. This indicates that the chemical reaction is triggered by thermal effects, not kinetic rates. Results from ideal-gas calculations show nearly identical chemical profiles inside the reactor in dimensionless distance. However, reactor residence times are overpredicted by nearly 150% using an ideal-gas assumption. Our results indicate that this oxidation process can be successfully modeled using gas-phase chemical mechanisms. 23 refs., 8 figs

Experimental investigation on thermal performance of a closed loop pulsating heat pipe (CLPHP) using methanol and distilled water at different filling ratios

Science.gov (United States)

Rahman, Md. Lutfor; Swarna, Anindita Dhar; Ahmed, Syed Nasif Uddin; Perven, Sanjida; Ali, Mohammad

2016-07-01

Pulsating Heat Pipes, the new two-phase heat transfer devices, with no counter current flow between liquid and vapor have become a modern topic for research in the field of thermal management. This paper focuses on the performance of methanol and distilled water as working fluid in a closed loop pulsating heat pipe (CLPHP). This performances are compared in terms of thermal resistance, heat transfer co-efficient, and evaporator and condenser wall temperature with variable heat inputs. Methanol and Distilled water are selected for their lower surface tension, dynamic viscosity and sensible heat. A closed loop PHP made of copper with 2mm ID and 2.5mm OD having total 8 loops are supplied with power input varied from 10W to 60W. During the experiment the PHP is kept vertical, while the filling ratio (FR) is increased gradually from 40% to 70% with 10% increment. The optimum filling ratio for a minimum thermal resistance is found to be 60% and 40% for distilled water and methanol respectively and methanol is found to be the better working fluid compared to distilled water in terms of its lower thermal resistance and higher heat transfer coefficient.

Determination and modeling of the solubility of (limonin in methanol or acetone + water) binary solvent mixtures at T = 283.2 K to 318.2 K

International Nuclear Information System (INIS)

Fan, Jie-Ping; Zheng, Bing; Liao, Dan-Dan; Yu, Jia-Xin; Cao, Ya-Hui; Zhang, Xue-Hong; Zhu, Jian-Hang

2016-01-01

Highlights: • The solubilities of limonin were measured in the binary solvent mixtures methanol + water and acetone + water. • The solubility data were correlated by nine models. • The solubility of limonin had a maximum point at 0.9 mol fraction of acetone in acetone + water mixtures. - Abstract: The solubility of limonin in the binary solvent mixtures (methanol + water) and (acetone + water) with various initial mole fractions of methanol or acetone was measured by high-performance liquid chromatography (HPLC) at different temperatures ranging from 283.2 K to 318.2 K. The solubility of limonin increased with increasing initial mole fraction of methanol in (methanol + water) mixtures, whereas it had a maximum point at 0.9 mol fraction of acetone in (acetone + water) mixtures. The solubility of limonin increased with increasing temperature in the two binary solvent mixtures. The solubility of limonin was correlated with temperature by the van’t Hoff model and the modified Apelblat model, and the fitting results showed that the modified Apelblat model had better correlation. The CNIBS/Redlich–Kister model and the simplified CNIBS/Redlich–Kister model were used to correlate the solubility data with the initial solvent composition, the results show that the CNIBS/Redlich–Kister model reveals better agreement with the experimental values. Furthermore, to illustrate the effects of both temperature and initial solvent composition on the changes in the solubility of limonin, the solubility values were fitted by the Jouyban–Acree, van’t Hoff–Jouyban–Acree, modified Apelblat–Jouyban–Acree, Ma and Sun models. Among the five models, the Jouyban–Acree model give the best correlation results for (methanol + water) binary solvent mixtures, while the experimental solubility in the (acetone + water) system was most accurately correlated by the van’t Hoff–Jouyban–Acree model.

(Liquid + liquid) equilibrium of (dibutyl ether + methanol + water) at different temperatures

International Nuclear Information System (INIS)

Arce, Alberto; Rodriguez, Hector; Rodriguez, Oscar; Soto, Ana

2005-01-01

(Liquid + liquid) equilibrium data for the ternary system (dibutyl ether + methanol + water) were experimentally determined at T = (298.15, 308.15, and 318.15) K. The experimental results were correlated by means of the NRTL and UNIQUAC equations, the best results being achieved with the UNIQUAC equation, both for the individual correlations at each temperature and for the overall correlation considering all the three experimental data sets. The experimental tie-lines were also compared to the values predicted by the UNIFAC method

SORPTION OF 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN TO SOILS FROM WATER/METHANOL MIXTURES

Science.gov (United States)

Sorption of 14C-labeled 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) to soils from water/methanol mixtures has been evaluated by batch shake testing. Uncontaminated soils from Times Beach, MO, were used in these experiments and ranged in fraction organic carbon (U...

Biodiesel Production from Acidified Oils via Supercritical Methanol

Directory of Open Access Journals (Sweden)

Jianxin Li

2011-12-01

Full Text Available In biodiesel production, the vegetable oil used as raw material for transesterification should be free of water and free fatty acids (FFAs, which may consume catalyst and reduce catalyst efficiency. In this work biodiesel was prepared from acidified oils (AO through a supercritical methanol route, in which the esterification of FFAs and transesterification of glyceride with methanol occurred simultaneously. The effects of the mass ratio of methanol to AO, the operation temperature as well as the water content on the FFAs conversion and glycerol yield were investigated. The results indicated that the FFAs conversion for esterification under the condition of 1:1 methanol/oil ratio, 310 °C and 15 min reaction time reached 98.7%, and the glycerol yield for transesterification under 0.25:1 methanol/oil ratio, 290 °C and 20 min reaction time reached 63.5% respectively.

Radiolysis of kaempferol in water/methanol mixtures. Evaluation of antioxidant activity of kaempferol and products formed.

Science.gov (United States)

Marfak, Abdelghafour; Trouillas, Patrick; Allais, Daovy-Paulette; Champavier, Yves; Calliste, Claude-Alain; Duroux, Jean-Luc

2003-02-26

Oxidative reaction between hydroxymethyl radical ((*)CH(2)OH) and kaempferol, in methanol and methanol/water mixtures, was studied by gamma-radiolysis using a (60)Co source. Radiolysis was performed with concentrations and doses ranging from 5 x 10(-)(5) M to 5 x 10(-)(3) M and from 0.5 kGy to 14 kGy, respectively. Kaempferol degradation was followed by HPLC. Results showed that (*)CH(2)OH reacts with kaempferol at the 3-OH group and produces two depsides (K1 and K2) and other products including K3. K1, K2, and K3 were identified by NMR, LC-MS, and HRMS. The kaempferol degradation pathway leading to the K1, K2, and K3 formation is proposed. It was observed that the more water concentration in the irradiation medium increases, the more K2 concentration increases. Comprehension of food preservation is not clear because many phenomena occurring during irradiation are not established. Radiolysis of kaempferol in water/methanol mixtures helps to elucidate the phenomenon and it is possible that during the treatment of nutriments by gamma-irradiation, a series of products such as depside K2 could be formed. Antioxidant properties of kaempferol radiolysis products were evaluated according to their capacity to decrease the EPR DPPH (1,1-diphenyl-2-picrylhydrazil) signal and to inhibit superoxide radicals formed by the enzyme reaction "xanthine + xanthine oxidase".

The onset of ion solvation by ab initio calculations: Comparison of water and methanol

Czech Academy of Sciences Publication Activity Database

Pluhařová, Eva; Jungwirth, Pavel

2008-01-01

Roč. 73, 6/7 (2008), s. 733-744 ISSN 0010-0765 R&D Projects: GA MŠk LC512; GA ČR GA203/07/1006 Institutional research plan: CEZ:AV0Z40550506 Keywords : ions * water cluster * methanol * ab initio calculations Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 0.784, year: 2008

Phospholipid composition of Dipylidium caninum.

Science.gov (United States)

Chopra, A K; Jain, S K; Vinayak, V K; Khuller, G K

1978-11-15

The phospholipid composition of Dipylidium caninum has been studied. Chloroform-methanol-soluble fraction amounted to 2.4% and phospholipids to 0.5% of the wet weight of the parasite. Phosphatidyl choline and phosphatidyl ethanolamine represented the bulk of the phospholipids, whereas phosphatidyl serine, phosphatidyl inositol, lysolecithin and lysophosphatidyl ethanolamine were present in minor amounts. Sulfatides were also identified in this parasite.

A Non-Heme Iron Photocatalyst for Light-Driven Aerobic Oxidation of Methanol

NARCIS (Netherlands)

Chen, Juan; Stepanovic, Stepan; Draksharapu, Apparao; Gruden, Maja; Browne, Wesley R

2018-01-01

Non-heme (L)FeIIIand (L)FeIII-O-FeIII(L) complexes (L=1,1-di(pyridin-2-yl)-N,N-bis(pyridin-2-ylmethyl)ethan-1-amine) underwent reduction under irradiation to the FeIIstate with concomitant oxidation of methanol to methanal, without the need for a secondary photosensitizer. Spectroscopic and DFT

Fast Measurement of Methanol Concentration in Ionic Liquids by Potential Step Method

Directory of Open Access Journals (Sweden)

Michael L. Hainstock

2015-01-01

Full Text Available The development of direct methanol fuel cells required the attention to the electrolyte. A good electrolyte should not only be ionic conductive but also be crossover resistant. Ionic liquids could be a promising electrolyte for fuel cells. Monitoring methanol was critical in several locations in a direct methanol fuel cell. Conductivity could be used to monitor the methanol content in ionic liquids. The conductivity of 1-butyl-3-methylimidazolium tetrafluoroborate had a linear relationship with the methanol concentration. However, the conductivity was significantly affected by the moisture or water content in the ionic liquid. On the contrary, potential step could be used in sensing methanol in ionic liquids. This method was not affected by the water content. The sampling current at a properly selected sampling time was proportional to the concentration of methanol in 1-butyl-3-methylimidazolium tetrafluoroborate. The linearity still stood even when there was 2.4 M water present in the ionic liquid.

Predicting soil-water partitioning of polycyclic aromatic hydrocarbons and polychlorinated biphenyls by desorption with methanol-water mixtures at different temperatures.

Science.gov (United States)

Krauss, M; Wilcke, W

2001-06-01

We evaluated a method to determine organic carbon-normalized soil-water partition coefficients (Koc) of 20 PAHs and 12 PCBs by desorption in the presence of a cosolvent (methanol fractions of 0.1-0.9) and at different temperatures (20-80 degrees C). The Koc values, the deviation factor from ideal sorption alpha, and the desorption enthalpies delta Hdes were estimated by nonlinear regression of log Koc on the methanol fractions and on T. The Koc values of individual compounds varied up to a factor of 100 among the studied 11 urban soils. The calculated alpha and delta Hdes of individual compounds varied considerably among the soils (coefficients of variation 5-20% and 20-30%, respectively), alpha increased with increasing hydrophobicity of the compounds. A sequential extraction with four temperature/methanol fraction combinations followed by a nonlinear regression allowed for the direct determination of the Koc, alpha, and delta Hdes. The use of less temperature/methanol fraction combinations requires a suitable estimation of alpha and delta Hdes, as their choice may change the obtained Koc values by up to a factor of 10. The proposed method is suitable for a routine determination of Koc values of PAHs and PCBs for small soil samples (2-6 g) and low concentrations (down to 0.3 mg kg-1 of sigma 20 PAHs and 1.2 micrograms kg-1 of sigma 12 PCBs).

Investigation by response surface methodology of the combined effect of pH and composition of water-methanol mixtures on the stability of curcuminoids.

Science.gov (United States)

D'Archivio, Angelo Antonio; Maggi, Maria Anna

2017-03-15

Response surface methodology, coupled to a full factorial three-level experimental design, was applied to investigate the combined influence of pH (between 7.0 and 8.6) and composition of methanol-water mixtures (between 30 and 70% v/v of methanol content) on the stability of curcumin and its analogues demethoxycurcumin and bisdemethoxycurcumin. The response plots revealed that addition of methanol noticeably improved the stability of curcuminoids, this effect being both pH- and structure-dependent. In the central point of the experimental domain, half-life times of curcumin, demethoxycurcumin and bisdemethoxycurcumin were 3.8±0.2, 27±2 and 251±17h, respectively. Stability of curcuminoids increased at lower pH and higher methanol content and decreased in the opposite vertex of the experimental domain. These results can be interpreted by assuming that addition of methanol to water produces a different variation of pH of the medium and apparent pKa values of the ionisable groups of curcuminoids. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of sorbed methanol, current, and temperature on multicomponent transport in nafion-based direct methanol fuel cells.

Science.gov (United States)

Rivera, Harry; Lawton, Jamie S; Budil, David E; Smotkin, Eugene S

2008-07-24

The CO2 in the cathode exhaust of a liquid feed direct methanol fuel cell (DMFC) has two sources: methanol diffuses through the membrane electrode assembly (MEA) to the cathode where it is catalytically oxidized to CO2; additionally, a portion of the CO2 produced at the anode diffuses through the MEA to the cathode. The potential-dependent CO2 exhaust from the cathode was monitored by online electrochemical mass spectrometry (ECMS) with air and with H2 at the cathode. The precise determination of the crossover rates of methanol and CO2, enabled by the subtractive normalization of the methanol/air to the methanol/H2 ECMS data, shows that methanol decreases the membrane viscosity and thus increases the diffusion coefficients of sorbed membrane components. The crossover of CO2 initially increases linearly with the Faradaic oxidation of methanol, reaches a temperature-dependent maximum, and then decreases. The membrane viscosity progressively increases as methanol is electrochemically depleted from the anode/electrolyte interface. The crossover maximum occurs when the current dependence of the diffusion coefficients and membrane CO2 solubility dominate over the Faradaic production of CO2. The plasticizing effect of methanol is corroborated by measurements of the rotational diffusion of TEMPONE (2,2,6,6-tetramethyl-4-piperidone N-oxide) spin probe by electron spin resonance spectroscopy. A linear inverse relationship between the methanol crossover rate and current density confirms the absence of methanol electro-osmotic drag at concentrations relevant to operating DMFCs. The purely diffusive transport of methanol is explained in terms of current proton solvation and methanol-water incomplete mixing theories.

Membrane technologies for desalting seawater and managing water resources; Le tecnologie di membrana per la dissalazione dell'acqua di mare e la gestione della risorsa idrica

Energy Technology Data Exchange (ETDEWEB)

Pizzichini, M. [ENEA, Divisione Biotecnologie e Agricoltura, Rome (Italy); Braccio, G. [ENEA, Divisione Fonti Rinnovabili, Rome (Italy); Bozzini, A. [Food and Agriculture Organization of the United Nations, Rome (Italy)

2001-04-01

Water is an irreplaceable resource for life that fundamentally conditions human economic and social development, especially in arid regions. Clean technologies such as membrane separation processes, in particular reverse osmosis, whether or not coupled with photovoltaic technology, can solve local water-deficit problems that jeopardise development and human life itself. The commercialisation of these systems offers an interesting opportunity for Italian manufacturers. [Italian] L'acqua e' una fonte di vita insostituibile che condiziona profondamente lo sviluppo economico e sociale dell'uomo, specialmente nelle aree geografiche aride. L'impiego di tecnologie pulite come i processo separativi a membrana, in particoalre di osmosi inversa accoppiati o meno alla tecnologia fotovoltaica, possono risolvere problemi locali di carenza idrica che mettono a rischio lo sviluppo e la vita stessa delle popolazioni.

New modelling method for fast reactor neutronic behaviours analysis; Nouvelles methodes de modelisation neutronique des reacteurs rapides de quatrieme Generation

Energy Technology Data Exchange (ETDEWEB)

Jacquet, P.

2011-05-23

Due to safety rules running on fourth generation reactors' core development, neutronics simulation tools have to be as accurate as never before. First part of this report enumerates every step of fast reactor's neutronics simulation implemented in current reference code: ECCO. Considering the field of fast reactors that meet criteria of fourth generation, ability of models to describe self-shielding phenomenon, to simulate neutrons leakage in a lattice of fuel assemblies and to produce representative macroscopic sections is evaluated. The second part of this thesis is dedicated to the simulation of fast reactors' core with steel reflector. These require the development of advanced methods of condensation and homogenization. Several methods are proposed and compared on a typical case: the ZONA2B core of MASURCA reactor. (author) [French] Les criteres de surete qui regissent le developpement de coeurs de reacteurs de quatrieme generation implique l'usage d'outils de calcul neutronique performants. Une premiere partie de la these reprend toutes les etapes de modelisation neutronique des reacteurs rapides actuellement d'usage dans le code de reference ECCO. La capacite des modeles a decrire le phenomene d'autoprotection, a representer les fuites neutroniques au niveau d'un reseau d'assemblages combustibles et a generer des sections macroscopiques representatives est appreciee sur le domaine des reacteurs rapides innovants respectant les criteres de quatrieme generation. La deuxieme partie de ce memoire se consacre a la modelisation des coeurs rapides avec reflecteur acier. Ces derniers necessitent le developpement de methodes avancees de condensation et d'homogenisation. Plusieurs methodes sont proposees et confrontees sur un probleme de modelisation typique: le coeur ZONA2B du reacteur maquette MASURCA

Activity coefficients, interfacial tensions and retention in reversed-phase liquid chormatography on LiChrosorb RP-18 with methanol-water mixtures

NARCIS (Netherlands)

Hammers, W.E.; Meurs, G.J.; Ligny, C.L. de

1982-01-01

Literature data on activity coefficients of various solutes in water, of some tetraalkyl compounds in methanol-water mixture and of water in organic solvents have been correlated with the product of the molecular surface area of the solute and the solute-solvent interfacial tension at ambient

Groundwater issues relating to an Alaskan methanol spill

International Nuclear Information System (INIS)

Robertson, S.B.

1992-01-01

This paper reports on a Dec. 1989 methanol spill which resulted from sabotage to three railroad tank cars. Samples taken from nearby drinking-water wells and groundwater-monitoring wells were below the analytical detection limit. Monitoring well data demonstrated that groundwater flow was not toward local residential wells. Dilution by snow and subsequent freezing in the soil limited the downward spread of the methanol, an advantage not found in milder, more temperate conditions. Contaminated material was removed and processed to reclaim the methanol. Volatilization and biodegradation should remove any remaining methanol. Cleanup options were limited by the possible hazardous waste classification of the contaminated soil. The regulatory status of spilled methanol waste should be re-evaluated, especially if use of methanol as a motor fuel increases

A luminescent metal-organic framework for sensing methanol in ethanol solution.

Science.gov (United States)

Jin, Zhao; He, Hongming; Zhao, Huanyu; Borjigin, Tsolmon; Sun, Fuxing; Zhang, Daming; Zhu, Guangshan

2013-10-07

A new luminescent Zn-MOF has been synthesized under hydrothermal condition using a semi-rigid ligand H3pcoip (4-(2-carboxyphenoxy)isophthalic acid) is reported. The luminescence properties of 1 in methanol, ethanol, and water have been investigated. Interestingly, compound 1 has a unique response to methanol compared to ethanol and water. Moreover, 1 displays a turn-on switching property triggered by methanol solvent molecules and a high sensitivity towards methanol concentration as low as 2 × 10(-7) (V(MeOH)/V(total)) in ethanol solution. The results indicate that the Zn-MOF has potential application as a sensor for detecting methanol in ethanol solution with excellent selectivity and high sensitivity.

Liquid methanol under a static electric field

Energy Technology Data Exchange (ETDEWEB)

Cassone, Giuseppe, E-mail: giuseppe.cassone@impmc.upmc.fr [Sorbonne Universités, UPMC Univ Paris 06, UMR 7590, IMPMC, F-75005 Paris (France); CNRS, UMR 7590, IMPMC, F-75005 Paris (France); Università degli Studi di Messina, Dipartimento di Fisica e di Scienze della Terra, Contrada Papardo, 98166 Messina (Italy); CNR-IPCF, Viale Ferdinando Stagno d’Alcontres 37, 98158 Messina (Italy); Giaquinta, Paolo V., E-mail: paolo.giaquinta@unime.it [Università degli Studi di Messina, Dipartimento di Fisica e di Scienze della Terra, Contrada Papardo, 98166 Messina (Italy); Saija, Franz, E-mail: saija@ipcf.cnr.it [CNR-IPCF, Viale Ferdinando Stagno d’Alcontres 37, 98158 Messina (Italy); Saitta, A. Marco, E-mail: marco.saitta@impmc.upmc.fr [Sorbonne Universités, UPMC Univ Paris 06, UMR 7590, IMPMC, F-75005 Paris (France); CNRS, UMR 7590, IMPMC, F-75005 Paris (France)

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.

Type II supernovae modelisation: neutrinos transport simulation

International Nuclear Information System (INIS)

Mellor, P.

1988-10-01

A modelisation of neutrino transport in type II supernovae is presented. The first part is a description of hydrodynamics and radiative processes responsible of supernovae explosions. Macroscopic aspects of these are displayed in part two. Neutrino transport theory and usual numerical methods are also developed. A new technic of coherent scattering of neutrinos on nuclei or free nucleons is proposed in the frame work of the Lorentz bifluid approximation. This method deals with all numerical artifices (flux limiting schemes, closure relationship of Eddington moments) and allows a complete and consistent determination of the time-dependent neutrino distribution function for any value of the opacity, gradient of opacity and for all (relativistic) velocity fields of the diffusive medium. Part three is dedicated to microscopic phenomena (electronic capture, chimical composition, etc) which rule neutrinos emission-absorption mechanisms. The numerical treatments of those are presented, and some applications are useful for their parametrization. Finally, an extension of the method to inelastic scattering on light particules (electrons) is described in view to study neutrinos thermalization mechanism [fr

Evaluation of SG blowdown demineralizer performance by replacement of ammonia with ethanolamine as a PWR secondary pH control agent

Energy Technology Data Exchange (ETDEWEB)

Rhee, I.H. [Department of Materials and Chemical Engineering, Soonchunhyang Univ. (Korea, Republic of); Yim, S.J. [Operation Management Team, Korea Hydro and Nuclear Power Co. Ltd., Seoul (Korea, Republic of)

2002-07-01

Four Korean PWR plants have adopted ethanolamine (ETA) as a secondary pH control agent to increase the pH at the liquid phase, which raises the pH in the SG blowdown system. The run time of the SG blowdown demineralizer can be reduced by the increased number of ionic chemical species primarily due to ETA. Contrary to the possible prevention of SG degradation, the replacement of ammonia with ETA results in the water chemistry difficulties and more frequent generation of spent resin. A comprehensive experimental data set for binary, ternary, quaternary, and quinary cation and anion adsorption was developed from small-volume batch tests at total cation or anion concentrations of 0.01 and 0.05 N to obtain the selectivity coefficients of many cations and anions normally present in the PWR secondary system water. In addition, the kinetic study using the bench-scale column was performed to examine the breakthrough point of an ion and to calculate the ratio of inlet to outlet concentration at the column, so called Decontamination Factor, in the different background electrolyte. The batch equilibrium tests indicated that the ion selectivity is higher for an ion of higher valence and is not uniform in the different composition and ionic strength. The preference of an ion on ion exchange resin rather tends to be lower with higher ionic strength. The leakage of an ion from the ion exchange column is not also uniform in time in the various composition and total concentration. Therefore the ion selectivity and breakthrough time are different in ammonia and ethanolamine background electrolytes. The run time of SG blowdown demineralizer can be shorter than it can be expected due to the elevated ionic strength as well as the increased dissolved solids. The quantitative run time can be estimated by such ion exchange models as semi-empirical mass action and surface complexation models. The demineralizer can be used longer by increasing the ratios of cation to anion exchange resins in

Evaluation of SG blowdown demineralizer performance by replacement of ammonia with ethanolamine as a PWR secondary pH control agent

International Nuclear Information System (INIS)

Rhee, I.H.; Yim, S.J.

2002-01-01

Four Korean PWR plants have adopted ethanolamine (ETA) as a secondary pH control agent to increase the pH at the liquid phase, which raises the pH in the SG blowdown system. The run time of the SG blowdown demineralizer can be reduced by the increased number of ionic chemical species primarily due to ETA. Contrary to the possible prevention of SG degradation, the replacement of ammonia with ETA results in the water chemistry difficulties and more frequent generation of spent resin. A comprehensive experimental data set for binary, ternary, quaternary, and quinary cation and anion adsorption was developed from small-volume batch tests at total cation or anion concentrations of 0.01 and 0.05 N to obtain the selectivity coefficients of many cations and anions normally present in the PWR secondary system water. In addition, the kinetic study using the bench-scale column was performed to examine the breakthrough point of an ion and to calculate the ratio of inlet to outlet concentration at the column, so called Decontamination Factor, in the different background electrolyte. The batch equilibrium tests indicated that the ion selectivity is higher for an ion of higher valence and is not uniform in the different composition and ionic strength. The preference of an ion on ion exchange resin rather tends to be lower with higher ionic strength. The leakage of an ion from the ion exchange column is not also uniform in time in the various composition and total concentration. Therefore the ion selectivity and breakthrough time are different in ammonia and ethanolamine background electrolytes. The run time of SG blowdown demineralizer can be shorter than it can be expected due to the elevated ionic strength as well as the increased dissolved solids. The quantitative run time can be estimated by such ion exchange models as semi-empirical mass action and surface complexation models. The demineralizer can be used longer by increasing the ratios of cation to anion exchange resins in

Effect of Drought Stress and Methanol on Chlorophyll Parameters, Chlorophyll Content and Relative Water Content of Soybean (Glycine max L., var. L 17

Directory of Open Access Journals (Sweden)

M Mirakhori

2011-01-01

Full Text Available Abstract In order to investigate the effects of methanol application on some physiological properties of soybean under low water stress, a factorial experiment was conducted at Research Field of Faculty of Agriculture and Natural Resources, Islamic Azad University-Karaj Branch, Karaj, Iran, during 2008, based on a randomized complete block design with three replications. The first factor was consisted of different levels of methanol equal to 0 (control, 7, 14, 21, 28 and 35 volumetric percentage (v/v, which were used as foliar applications at three times during growth season of soybean, with 15 days intervals. The second factor was water stress conditions in two levels, based on depletion of 40 and 70% of available soil moisture. Some traits such as grain yield (GY, relative water content (RWC, chlorophyll fluorescence parameters, and chlorophyll content were measured, one day before and after the third methanol application. Results showed that chlorophyll content (Chl, GY, electrolytes leakage (EL at second sampling, photochemical capacity of PSII (Fv/Fm, maximum and variable fluorescence (Fm and FV, respectively were affected by water stress significantly (p

Modelisation of the concentration of macromolecules moving in a Newtonian fluid

International Nuclear Information System (INIS)

Hijazi, A.; Zoaeter, M.; Khater, A.; Aussere, D.

1998-01-01

Author.This article presents a modelisation of the distribution of a diluted solution of macromolecules submitted to a simple flow in the neighborhood of a non-absorbing solid surface. These macromolecules (length L, negligible diameter) are submitted to two kinds of forces: rotational and translational with brownian and hydrodynamic origins. The evolution of orientation of these molecules in terms of time has been studied, given Einstein equation =D with D coefficient of translation and rotation. By taking as parameters the orientation θ of the macromolecules with respect to an horizontal axis and Z the distance between these macromolecules and the surface, a statistical study has led to determine the distribution. For that reason, the brownian movement considered is supposed to follow a rule of random probability

Atmospheric deposition of methanol over the Atlantic Ocean

Science.gov (United States)

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

Development of methanol evaporation plate to reduce methanol crossover in a direct methanol fuel cell

Science.gov (United States)

Zhang, Ruiming

This research focuses on methanol crossover reduction in direct methanol fuel cells (DMFC) through separating the methanol vapor from its liquid phase and feeding the vapor passively at low temperature range. Membrane electrode assemblies (MEAs) were fabricated by using commercial available membrane with different thickness at different anode catalyst loading levels, and tested under the operating conditions below 100°C in cell temperature and cathode exit open to ambient pressure. Liquid methanol transport from the anode through the membrane into cathode ("methanol crossover") is identified as one of the major efficiency losses in a DMFC. It is known that the methanol crossover rate in the vapor phase is much lower than in liquid phase. Vapor feed can be achieved by heating the liquid methanol to elevated temperatures (>100°C), but other issues limit the performance of the cell when operating above 100°C. High temperature membranes and much more active cathode catalyst structures are required, and a complex temperature control system must be employed. However, methanol vapor feed can also occur at a lower temperature range (evaporation through a porous body. The methanol crossover with this vapor feed mode is lower compared with the direct liquid methanol feed. A new method of using a methanol evaporation plate (MEP) to separate the vapor from its liquid phase to reduce the liquid methanol crossover at low temperature range is developed. A MEP plays the roles of liquid/vapor methanol phase separation and evaporation in a DMFC. The goal of this study is to develop a MEP with the proper properties to achieve high methanol phase separation efficiency and fast methanol evaporation rate over a wide range of temperature, i.e., from room temperature up to near boiling temperature (100°C). MEP materials were selected and characterized. MEPs made from three different types were tested extensively with different MEA and porous back layer configurations. The benefits of

Preferential solvation of single ions in mixed solvents: Part 1. New experimental approach and solvation of monovalent ions in methanol-water and acetonitrile-water mixture. Part 2. Theoretical computation and comparison with experimental data

International Nuclear Information System (INIS)

Rege, Aarti C.; Venkataramani, B.; Gupta, A.R.

1999-06-01

Preferential solvation of single ion solutions has been studied with Li + , Na + , K + and Ag +- forms of Dowex 50W resins of different cross-linkings in methanol-water and acetonitrile (AN)- water mixtures. The solvent uptake by this alkali metal ionic forms of Dowex 50W resins was studied in an isopiestic set-up using 2,4,6 and 8 m LiCl solutions in 11.0, 20.8, 44.3 and 70.2 % (w/w) methanol-water mixtures and that of Na +- and Ag +- forms using 14.6 to 94.3 % (w/w) AN - water mixtures. The solvent sorbed in the resin phase was extracted by Rayleigh-type distillation and analysed gas chromatographically. The data were analysed by the N s (mole fraction of the organic solvent in the resin phase) vs n t au (total solvent content in the resin phase) plots and separation factor, alpha(ratio of mole fraction of the solvents in the resin and solution phases) or N s vs m (molality in the resin phase) plots. The limiting values of these plots gave the composition of the solvent in the primary solvation shell around the single ion. The compositions of the primary solvation shell around Li + , Na + , and K + in methanol-water mixtures and Na + and Ag + in acetonitrile (AN) - water mixtures have been computed using Franks equation and the approach of Marcus and compared with the experimental results obtained with the above mentioned ionic forms of Dowex 50W resins in different mixed solvents. The experimental results for Li + showed good agreement with the values computed using Franks equation for all methanol-water composition. However, in the case of Na + and K + in methanol-water mixtures and Na + in AN-water mixtures, there was agreement only at lower organic solvent content and the Franks equation predicted higher values for the organic solvent in the primary solvation shell around the cation at higher organic solvent content as compared to experimental results

Bifunctional anode catalysts for direct methanol fuel cells

DEFF Research Database (Denmark)

Rossmeisl, Jan; Ferrin, Peter; Tritsaris, Georgios

2012-01-01

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....... 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....

Effects on water quality from mud clearance operations in the Pezze' hydropower basin (Trentino, Italy); Effetti sulla qualita' delle acque legati alle operazioni di dissabbiamento del bacino idroelettrico di Pezze' di Moena (Trentino)

Energy Technology Data Exchange (ETDEWEB)

Canepel, R.; Cadrobbi, G.; Fedrizzi, F. [Agenzia Provinciale per la Protezione dell' Ambiente, Trent (Italy)

2000-07-01

The present paper describes dynamic concentration for various parameters, that have been monitored through both continuous and instant samplings, during maintenance operations (mud deposit clearance) in a hydropower basin along Torrent Avisio in Trentino region, Italy. Aim of the work is to demonstrate that, during such operations, an organic water pollution occur besides turbidity. The former is well expressed by a marked value increment of different parameters, as total phosphorus, ammonium and organic matter. [Italian] Il presente lavoro descrive l'osservazione dell'andamento delle concentrazioni di diversi parametri, rilevati in continuo e attraverso campionamenti istantanei, durante le operazioni di dissabbiamento di un bacino idroelettrico lungo un corso d'acqua, il Torrente Avisio in Trentino. Scopo del lavoro e' la dimostrazione della consistenza, in occasione di tali eventi, di un inquinamento delle acque, oltre che di tipo inorganico (intorbidimento), anche di tipo organico cioe' caratterizzato da uno spiccato incremento, rispetto alle condizioni normali, di una serie di parametri fra cui fosforo totale, azoto ammoniacale e sostanza organica.

A Simple Method for Automated Solid Phase Extraction of Water Samples for Immunological Analysis of Small Pollutants.

Science.gov (United States)

Heub, Sarah; Tscharner, Noe; Kehl, Florian; Dittrich, Petra S; Follonier, Stéphane; Barbe, Laurent

2016-01-01

A new method for solid phase extraction (SPE) of environmental water samples is proposed. The developed prototype is cost-efficient and user friendly, and enables to perform rapid, automated and simple SPE. The pre-concentrated solution is compatible with analysis by immunoassay, with a low organic solvent content. A method is described for the extraction and pre-concentration of natural hormone 17β-estradiol in 100 ml water samples. Reverse phase SPE is performed with octadecyl-silica sorbent and elution is done with 200 µl of methanol 50% v/v. Eluent is diluted by adding di-water to lower the amount of methanol. After preparing manually the SPE column, the overall procedure is performed automatically within 1 hr. At the end of the process, estradiol concentration is measured by using a commercial enzyme-linked immune-sorbent assay (ELISA). 100-fold pre-concentration is achieved and the methanol content in only 10% v/v. Full recoveries of the molecule are achieved with 1 ng/L spiked de-ionized and synthetic sea water samples.

Kinetics of methanol decomposition on Cu/ZnO/ZrO2 catalysts

International Nuclear Information System (INIS)

Grabowski, R.; Kozlowska, A.

2004-01-01

Interaction of methanol with Cu/ZnO/ZrO 2 (with different copper content) has been investigated by gravimetric and TPD methods. The TPD measurements of methanol adsorption on these catalysis show that it forms the complexes of two types. The first complex (I) decomposes at low temperature (453 K) yielding H 2 and CO 2 and second (II) decomposes at temperature (573 K) giving CO and H 2 . In the process of decomposition of the complex (I) takes part water which is adsorbed on the surface of the catalyst and the decomposition of the complex (II) occurs without participation of adsorbed water. Gravimetric measurements of methanol and that an increase of copper content leads to the changes in the kinetics of methanol adsorption and its decomposition. On the basis of gravimetric measurements a model of methanol adsorption and decomposition on Cu/ZnO/ZrO 2 catalyst has been proposed and the rate constants of methanol adsorption (k a ) and decomposition with and without participation of water (k 1 and k 2 ) have been determined. (author)

A fate for organic acids, formaldehyde and methanol in cloud water: their biotransformation by micro-organisms

Directory of Open Access Journals (Sweden)

P. Amato

2007-08-01

Full Text Available The interactions between microbial and chemical contents of cloud water were investigated. First, we observe that the bulk cloud water solution provides a substantial environment where bacteria can develop significantly. Then, a total number of 60 microbial strains originating from seven distinct samples of cloud water and affiliated to various taxonomic groups were examined for their ability to degrade some of the main atmospheric carboxylic compounds: formate, acetate, lactate, succinate, as well as formaldehyde and methanol. Biodegradation tests show that all these compounds can be transformed when used as single carbonaceous substrates, with activities depending on both the strain and the compound. The highest capacities of biodegradation are observed towards formaldehyde, formate and acetate, which are also the more concentrated compounds typically measured in cloud water. Hence, analyses by ¹H NMR permitted to establish for instance that compounds like pyruvate or fumarate can be produced and released in the media in relation to the transformation of lactate or succinate. In addition, utilization of ¹³C labelled formaldehyde showed that it can be transformed through many metabolic pathways, similar to those induced by photochemistry and leading to the production of formate and/or methanol. These results suggest that microorganisms of cloud water can have various behaviours towards the chemical compounds present in the atmosphere: they can represent either a sink or source for organic carbon, and may have to be considered as actors of cloud chemistry.

COMPARISON OF SORPTION ENERGTICS FOR HYDROPHOBIC ORGANIC CHEMICALS BY SYNTHETIC AND NATURAL SORBENTS FROM METHANOL/WATER SOLVENT MIXTURES

Science.gov (United States)

Reversed-phase liquid chromatography (RPLC) was used to investigate the thermodynamics and mechanisms of hydrophobic organic chemical (HOC) retention from methanol/water solvent mixtures. The enthalpy-entropy compensation model was used to infer that the hydro- phobic sorptive me...

Cm3+-F- interaction in a mixed system of methanol and water

International Nuclear Information System (INIS)

Satoh, I.; Watanabe, T.; Ishii, Y.; Kawasaki, M.; Suganuma, H.

2003-01-01

The stability constants (β 1 ) of the monofluoro complex of Cm(III) have been determined in mixed solvents of methanol and water using the solvent extraction technique. The values of Inβ 1 increase as the molar fraction of methanol (X s ) in the mixed solvent increases. The variation in the stability constants mainly depends on the solvation of F - and slightly depends on both (1) the solvation of cations in connection with the complexation of CmF 2+ and (2) the electrostatic attraction of Cm 3+ -F - . The variation in Inβ 1 for Cm(III) due to the effect of both (1) and (2) is similar to that for Sm(III). By variation of Inβ 1 the coordination number in the primary hydration sphere (CN) of Cm(III) decreased from a value between CN = 9 and CN = 8 to CN = 8, at about X s = 0.02. The X s value of the inflection point of the CN for Cm is slightly lower than X s = 0.06 for Sm(III) and X s = 0.03 for Eu(III), previously obtained. (author)

Surface-Bound Intermediates in Low-Temperature Methanol Synthesis on Copper. Participants and Spectators

Energy Technology Data Exchange (ETDEWEB)

Yang, Yong; Mei, Donghai; Peden, Charles HF; Campbell, Charles T.; Mims, Charles A.

2015-11-03

The reactivity of surface adsorbed species present on copper catalysts during methanol synthesis at low temperatures was studied by simultaneous infrared spectroscopy (IR) and mass spectroscopy (MS) measurements during “titration” (transient surface reaction) experiments with isotopic tracing. The results show that adsorbed formate is a major bystander species present on the surface under steady-state methanol synthesis reaction conditions, but it cannot be converted to methanol by reaction with pure H₂, nor with H₂ plus added water. Formate-containing surface adlayers for these experiments were produced during steady state catalysis in (a) H₂:CO₂ (with substantial formate coverage) and (b) moist H₂:CO (with no IR visible formate species). Both these reaction conditions produce methanol at steady state with relatively high rates. Adlayers containing formate were also produced by (c) formic acid adsorption. Various "titration" gases were used to probe these adlayers at modest temperatures (T = 410-450K) and 6 bar total pressure. Methanol gas (up to ~1% monolayer equivalent) was produced in "titration" from the H₂:CO₂ catalytic adlayers by H₂ plus water, but not by dry hydrogen. The decay in the formate IR features accelerated in the presence of added water vapor. The H₂:CO:H₂O catalytic adlayer produced similar methanol titration yields in H₂ plus water but showed no surface formate features in IR (less than 0.2% monolayer coverage). Finally, formate from formic acid chemisorption produced no methanol under any titration conditions. Even under (H₂:CO₂) catalytic reaction conditions, isotope tracing showed that pre-adsorbed formate from formic acid did not contribute to the methanol produced. Although non-formate intermediates exist during low temperature methanol synthesis on copper which can be converted to methanol gas

Monitoring of pesticides and nitrates on water, soil and agricultural production in the Bracciano lake district; Monitoraggio di pesticidi e nitrati nelle acque, suolo, e prodotti agricoli nel bacino del lago di Bracciano

Energy Technology Data Exchange (ETDEWEB)

Caffarelli, V; Correnti, A [ENEA, Div. Biotecnologie e Agricoltura, Centro Ricerche Casaccia, Rome (Italy); Cecchini, G; Frugis, A; Segatori, M [WRc Italia SpA, Gruppo ACEA, Centro di Ricerca e Sviluppo, Rome (Italy); Conte, E; Milani, R; Morali, G [Istituto Sperimentale per la Patologia Vegetale, Rome (Italy); Ciampi, G [Agenzia Regionale per l' Innovazione e lo Sviluppo in Agricoltura del Lazio, Rome (Italy)

2001-07-01

In the Bracciano Lake district, in actuation of the 2081/93 EEC, obj. 5b, a study was carried out, aimed to the realisation of a territorial informative system and supply technical support to the farmers for phyto pathological problems. A monitoring program has been realized for pesticide and nitrate in environmental samples and agricultural products. Five hundred and sixteen samples have been collected and analysed, from march 1999 to October 2000: 191 samples of water (ground and surface water), 20 samples of soil, 340 samples of agricultural products (vegetables and fruit). Pesticides were found in irrigation water and soil samples; the irregularities on agricultural products, 3% could disappear if the treatments are correct and respect the label indications. [Italian] In attuazione del regolamento 2081/93 ECC ob.5 b, nel bacino del lago di Bracciano, e' stato realizzato uno studio mirato alla realizzazione di un sistema informativo territoriale e a fornire un supporto tecnico per la gestione della difesa fitosanitaria della produzione agricola. Una campagna di monitoraggio e' stata realizzata per l'analisi della presenza di pesticidi in campioni ambientali e nei prodotti agricoli. Sono stati prelevati e analizzati 516 campioni nel periodo marzo '99. Ottobre 2000: 191 campioni di acque superficiali e di falda, 20 campioni di suolo, 340 campioni (frutta e vegetali). Pesticidi sono stati ritrovati nelle acque di irrigazione e nel suolo; la presenza di irregolarita' riscontrate nel 3% dei prodotti agricoli, e' da attribuire a un uso non corretto dei prodotti fitosanitari.

The effects of methanol on the trapping of volatile ice components

Science.gov (United States)

Burke, Daren J.; Brown, Wendy A.

2015-04-01

The evaporation of icy mantles, which have been formed on the surface of dust grains, is acknowledged to give rise to the rich chemistry that has been observed in the vicinity of hot cores and corinos. It has long been established that water ice is the dominant species within many astrophysical ices. However, other molecules found within astrophysical ices, particularly methanol, can influence the desorption of volatile species from the ice. Here we present a detailed investigation of the adsorption and desorption of methanol-containing ices, showing the effect that methanol has on the trapping and release of volatiles from model interstellar ices. OCS and CO2 have been used as probe molecules since they have been suggested to reside in water-rich and methanol-rich environments. Experiments show that methanol fundamentally changes the desorption characteristics of both OCS and CO2, leading to the observation of mainly codesorption of both species with bulk water ice for the tertiary ices and causing a lowering of the temperature of the volcano component of the desorption. In contrast, binary ices are dominated by standard volcano desorption. This observation clearly shows that codepositing astrophysically relevant impurities with water ice, such as methanol, can alter the desorption dynamics of volatiles that become trapped in the pores of the amorphous water ice during the sublimation process. Incorporating experimental data into a simple model to simulate these processes on astrophysical timescales shows that the additional methanol component releases larger amounts of OCS from the ice mantle at lower temperatures and earlier times. These results are of interest to astronomers as they can be used to model the star formation process, hence giving information about the evolution of our Universe.

Dynamic signature of molecular association in methanol

International Nuclear Information System (INIS)

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

2016-01-01

Quasielastic neutron scattering measurements and molecular dynamics simulations were combined to investigate the collective dynamics of deuterated methanol, CD 3 OD. 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.

Macroscopic Modeling of Transport Phenomena in Direct Methanol Fuel Cells

DEFF Research Database (Denmark)

Olesen, Anders Christian

An increasing need for energy efficiency and high energy density has sparked a growing interest in direct methanol fuel cells for portable power applications. This type of fuel cell directly generates electricity from a fuel mixture consisting of methanol and water. Although this technology...... surpasses batteries in important areas, fundamental research is still required to improve durability and performance. Particularly the transport of methanol and water within the cell structure is difficult to study in-situ. A demand therefore exist for the fundamental development of mathematical models...... for studying their transport. In this PhD dissertation the macroscopic transport phenomena governing direct methanol fuel cell operation are analyzed, discussed and modeled using the two-fluid approach in the computational fluid dynamics framework of CFX 14. The overall objective of this work is to extend...

Highly water-dispersible, mixed ionic-electronic conducting, polymer acid-doped polyanilines as ionomers for direct methanol fuel cells.

Science.gov (United States)

Murthy, Arun; Manthiram, Arumugam

2011-06-28

Highly water-dispersible polymer acid-doped polyanilines have been synthesized and evaluated as an alternative for expensive Nafion ionomers in the anode of direct methanol fuel cells (DMFC). These polymers as ionomers lead to higher performance in single cell DMFC compared to Nafion ionomers due to mixed ionic-electronic conduction, water dispersibility, and co-catalytic activity. This journal is © The Royal Society of Chemistry 2011

PERFORMANCE AND EMISSION STUDIES ON DI-DIESEL ENGINE FUELED WITH PONGAMIA METHYL ESTER INJECTION AND METHANOL CARBURETION

Directory of Open Access Journals (Sweden)

HARIBABU, N.

2010-03-01

Full Text Available The target of the present study is to clarify ignition characteristics, combustion process and knock limit of methanol premixture in a dual fuel diesel engine, and also to improve the trade-off between NOx and smoke markedly without deteriorating the high engine performance. Experiment was conducted to evaluate the performance and emission characteristics of direct injection diesel engine operating in duel fuel mode using Pongamia methyl ester injection and methanol carburetion. Methanol is introduced into the engine at different throttle openings along with intake air stream by a carburetor which is arranged at bifurcated air inlet. Pongamia methyl ester fuel was supplied to the engine by conventional fuel injection. The experimental results show that exhaust gas temperatures are moderate and there is better reduction of NOx, HC, CO and CO2 at methanol mass flow rate of 16.2 mg/s. Smoke level was observed to be low and comparable. Improved thermal efficiency of the engine was observed.

Calorimetric determination of enthalpies for the proton ionization of N,N-bis[2-hydroxyethyl]-2-aminoethanesulfonic acid (BES) and N-tris[hydroxymethyl]methyl-2-aminoethanesulfonic acid (TES) in water-methanol mixtures

International Nuclear Information System (INIS)

Bulos, B.N.; Jumean, F.H.

2004-01-01

The enthalpies of proton ionization of the biochemical buffers N,N-bis[2-hydroxyethyl]-2-aminoethanesulfonic acid (BES) and N-tris[hydroxymethyl]methyl-2-aminoethanesulfonic acid (TES) were obtained in water-methanol mixtures in which the methanol mole fraction (X m ) varied in the range 0-0.36. For both buffers, ionization enthalpy for the first proton (ΔH 1 ) was small in all solvent media. However, upon addition of methanol, ΔH 2 increased steadily from 22.2 to a maximum of 27.2 kJ mol -1 for BES, whereas for TES it varied from 30.0 to 32.4, with a minimum of 28.6 kJ mol -1 at X m =0.123. It is noteworthy that this solvent composition lies within the region of maximum structure enhancement of water by methanol. The results were interpreted in terms of methanol-water interactions

The Hydrolysis of Di-Isopropyl Methylphosphonate in Ground Water

Energy Technology Data Exchange (ETDEWEB)

Sega, G.A., Tomkins, B.A., Griest, W.H., Bayne, C.K.

1997-12-31

Di-isopropyl methylphosphonate (DIMP) is a byproduct from the manufacture of the nerve agent Sarin. The persistence of DIMP in the ground water is an important question in evaluating the potential environmental impacts of DIMP contamination. The half-life of DIMP in ground water at 10 deg C was estimated to be 500 years with a 95% confidence interval of 447 to 559 years from measurements of the hydrolysis rates at temperatures between 70 to 98 deg C.Extrapolation of the kinetics to 10 deg C used the Arrhenius equation, and calculation of the half-life assumed first-order kinetics. Inorganic phosphate was not detected.

Process for obtaining methanol. Verfahren zur Gewinnung von Methanol

Energy Technology Data Exchange (ETDEWEB)

Link, H; Watson, A

1983-12-08

Synthetic gas is generated and converted to methanol in a reactor. After the separation of the crude methanol, there is a multi-stage methanol distillation. Condensate occurring during distillation is at least partly fed back before the methanol synthesis.

Monitoring of pesticides and nitrates on water, soil and agricultural production in the Bracciano lake district; Monitoraggio di pesticidi e nitrati nelle acque, suolo, e prodotti agricoli nel bacino del lago di Bracciano

Energy Technology Data Exchange (ETDEWEB)

Caffarelli, V.; Correnti, A. [ENEA, Div. Biotecnologie e Agricoltura, Centro Ricerche Casaccia, Rome (Italy); Cecchini, G.; Frugis, A.; Segatori, M. [WRc Italia SpA, Gruppo ACEA, Centro di Ricerca e Sviluppo, Rome (Italy); Conte, E.; Milani, R.; Morali, G. [Istituto Sperimentale per la Patologia Vegetale, Rome (Italy); Ciampi, G. [Agenzia Regionale per l' Innovazione e lo Sviluppo in Agricoltura del Lazio, Rome (Italy)

2001-07-01

In the Bracciano Lake district, in actuation of the 2081/93 EEC, obj. 5b, a study was carried out, aimed to the realisation of a territorial informative system and supply technical support to the farmers for phyto pathological problems. A monitoring program has been realized for pesticide and nitrate in environmental samples and agricultural products. Five hundred and sixteen samples have been collected and analysed, from march 1999 to October 2000: 191 samples of water (ground and surface water), 20 samples of soil, 340 samples of agricultural products (vegetables and fruit). Pesticides were found in irrigation water and soil samples; the irregularities on agricultural products, 3% could disappear if the treatments are correct and respect the label indications. [Italian] In attuazione del regolamento 2081/93 ECC ob.5 b, nel bacino del lago di Bracciano, e' stato realizzato uno studio mirato alla realizzazione di un sistema informativo territoriale e a fornire un supporto tecnico per la gestione della difesa fitosanitaria della produzione agricola. Una campagna di monitoraggio e' stata realizzata per l'analisi della presenza di pesticidi in campioni ambientali e nei prodotti agricoli. Sono stati prelevati e analizzati 516 campioni nel periodo marzo '99. Ottobre 2000: 191 campioni di acque superficiali e di falda, 20 campioni di suolo, 340 campioni (frutta e vegetali). Pesticidi sono stati ritrovati nelle acque di irrigazione e nel suolo; la presenza di irregolarita' riscontrate nel 3% dei prodotti agricoli, e' da attribuire a un uso non corretto dei prodotti fitosanitari.

Integrative CO2 Capture and Hydrogenation to Methanol with Reusable Catalyst and Amine: Toward a Carbon Neutral Methanol Economy.

Science.gov (United States)

Kar, Sayan; Sen, Raktim; Goeppert, Alain; Prakash, G K Surya

2018-02-07

Herein we report an efficient and recyclable system for tandem CO 2 capture and hydrogenation to methanol. After capture in an aqueous amine solution, CO 2 is hydrogenated in high yield to CH 3 OH (>90%) in a biphasic 2-MTHF/water system, which also allows for easy separation and recycling of the amine and catalyst for multiple reaction cycles. Between cycles, the produced methanol can be conveniently removed in vacuo. Employing this strategy, catalyst Ru-MACHO-BH and polyamine PEHA were recycled three times with 87% of the methanol producibility of the first cycle retained, along with 95% of catalyst activity after four cycles. CO 2 from dilute sources such as air can also be converted to CH 3 OH using this route. We postulate that the CO 2 capture and hydrogenation to methanol system presented here could be an important step toward the implementation of the carbon neutral methanol economy concept.

Design of novel DME/methanol synthesis plants based on gasification of biomass

DEFF Research Database (Denmark)

Clausen, Lasse Røngaard

-scale DME plants based on gasification of torrefied biomass. 2. Small-scale DME/methanol plants based on gasification of wood chips. 3. Alternative methanol plants based on electrolysis of water and gasification of biomass. The plants were modeled by using the component based thermodynamic modeling...... why the differences, in biomass to DME/methanol efficiency, between the small-scale and the large-scale plants, showed not to be greater, was the high cold gas efficiency of the gasifier used in the small-scale plants (93%). By integrating water electrolysis in a large-scale methanol plant, an almost...... large-scale DME plant) to 63%, due to the relatively inefficient electrolyser....

GROUND WATER ASSESSMENT IN AGRICULTURAL AREA, CASE STUDY FROM MACHANG-MALAYSIA (Penilaian Air Tanah di Daerah Pertanian, Studi Kasus di Machang Malaysia

Directory of Open Access Journals (Sweden)

Nur Islami

2010-11-01

Full Text Available ABSTRACT The study area is located in Machang, North Kelantan - Malaysia. The North Kelantan plain is covered with Quaternary sediments overlying granite bedrock. The drainage system is dendritic with the main river flowing into the South China Sea. Hydrogeochemical method was used to study groundwater of shallow aquifer characters within the area. Based on water samples analysis collected from the study area, it can be deduced that the cations and anions concentration are good for domestic use except in the southern region which the nitrate concentration is higher (more than 20 mg/l compared to the northern region (relatively zero. The areas that possibly possess nitrate-contaminated groundwater have been mapped along with groundwater flow patterns. The southern and middle part of the study area has an east to west groundwater flow pattern, making it impossible for contaminated water from the southern region to enter the northern area, despite in the northern area has lower elevation. ABSTRAK Lokasi area studi adalah berada di Machang, Kelantan Utara – Malaysia. Dataran tanah wilayah Kelantan Utara dilapisi oleh batuan Sedimen Kuarter yang mana batuan granit sebagai batuan dasar. Sistem pengairan adalah berbentuk jaringan dendritik dengan sungai utama mengalir ke Laut Cina Selatan. Metoda hydrogeochemical digunakan untuk mempelajari karakter air tanah dari akuifer dangkal untuk keseluruhan area studi. Berdasarkan pada analisa air yang diperoleh dari area studi, dapat disimpulkan bahwa konsentrasi kation dan anion baik digunakan untuk kehidupan sehari hari kecuali air tanah di area sebelah selatan yang mana kandungan nitratnya tinggi (lebih dari 20 mg/l dibandingkan di area sebelah utara (hampir tidak ada kandungan nitrat. Area yang memungkinkan memiliki konsentrasi nitrat pada air tanah dipetakan dengan kombinasi pola aliran air tanah. Pola aliran air tanah di area belahan selatan dan bagian tengah adalah dari timur ke barat yang mana tidak

Petroleum Refinery Effluents Treatment by Advanced Oxidation Process with Methanol

Energy Technology Data Exchange (ETDEWEB)

Shoucheng, Wen [Yangtze Univ., HuBei Jingzhou (China)

2014-02-15

Petroleum refinery effluents are waste originating from industries primarily engaged in refining crude oil. It is a very complex compound of various oily wastes, water, heavy metals and so on. Conventional processes are unable to effectively remove the chemical oxygen demand (COD) of petroleum refinery effluents. Supercritical water oxidation (SCWO) was proposed to treat petroleum refinery effluents. In this paper, methanol was used to investigate co-oxidative effect of methanol on petroleum refinery effluents treatment. The results indicated that supercritical water oxidation is an effective process for petroleum refinery effluents treatment. Adding methanol caused an increase in COD removal. When reaction temperature is 440 .deg. C, residence time is 20 min, OE is 0.5 and initial COD is 40000 mg/L, and COD removal increases 8.5%.

Petroleum Refinery Effluents Treatment by Advanced Oxidation Process with Methanol

International Nuclear Information System (INIS)

Shoucheng, Wen

2014-01-01

Petroleum refinery effluents are waste originating from industries primarily engaged in refining crude oil. It is a very complex compound of various oily wastes, water, heavy metals and so on. Conventional processes are unable to effectively remove the chemical oxygen demand (COD) of petroleum refinery effluents. Supercritical water oxidation (SCWO) was proposed to treat petroleum refinery effluents. In this paper, methanol was used to investigate co-oxidative effect of methanol on petroleum refinery effluents treatment. The results indicated that supercritical water oxidation is an effective process for petroleum refinery effluents treatment. Adding methanol caused an increase in COD removal. When reaction temperature is 440 .deg. C, residence time is 20 min, OE is 0.5 and initial COD is 40000 mg/L, and COD removal increases 8.5%

Calorimetric determination of enthalpies for the proton ionization of N,N-bis[2-hydroxyethyl]-2-aminoethanesulfonic acid (BES) and N-tris[hydroxymethyl]methyl-2-aminoethanesulfonic acid (TES) in water-methanol mixtures

Energy Technology Data Exchange (ETDEWEB)

Bulos, B.N.; Jumean, F.H

2004-02-19

The enthalpies of proton ionization of the biochemical buffers N,N-bis[2-hydroxyethyl]-2-aminoethanesulfonic acid (BES) and N-tris[hydroxymethyl]methyl-2-aminoethanesulfonic acid (TES) were obtained in water-methanol mixtures in which the methanol mole fraction (X{sub m}) varied in the range 0-0.36. For both buffers, ionization enthalpy for the first proton ({delta}H{sub 1}) was small in all solvent media. However, upon addition of methanol, {delta}H{sub 2} increased steadily from 22.2 to a maximum of 27.2 kJ mol{sup -1} for BES, whereas for TES it varied from 30.0 to 32.4, with a minimum of 28.6 kJ mol{sup -1} at X{sub m}=0.123. It is noteworthy that this solvent composition lies within the region of maximum structure enhancement of water by methanol. The results were interpreted in terms of methanol-water interactions.

Formaldehyde, methanol and hydrocarbon emissions from methanol-fueled cars

International Nuclear Information System (INIS)

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

1990-01-01

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

Effects of temperature and feed composition on catalytic dehydration of methanol to dimethyl ether over {gamma}-alumina

Energy Technology Data Exchange (ETDEWEB)

Freshteh Raoof; Majid Taghizadeh; Ali Eliassi; Fereydoon Yaripour [Babol University of Technology, Babol (Iran). Chemical Engineering Department

2008-10-15

Catalytic dehydration of methanol to dimethyl ether (DME) is performed in an adiabatic fixed bed heterogeneous reactor by using acidic {gamma}-alumina. By changing the mean average temperature of the catalyst bed (or operating temperature of the reactor) from 233 up to 303{sup o}C, changes in methanol conversion were monitored. The results showed that the conversion of methanol strongly depended on the reactor operating temperature. Also, conversion of pure methanol and mixture of methanol and water versus time were studied and the effect of water on deactivation of the catalyst was investigated. The results revealed that when pure methanol was used as the process feed, the catalyst deactivation occurred very slowly. But, by adding water to the feed methanol, the deactivation of the {gamma}-alumina was increased very rapidly; so much that, by increasing water content to 20 weight percent by weight, the catalyst lost its activity by about 12.5-fold more than in the process with pure methanol. Finally, a temperature dependent model developed to predict pure methanol conversion to DME correlates reasonably well with experimental data. 11 refs., 9 figs., 3 tabs.

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

Science.gov (United States)

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.

Ground waters quality assessment near solid municipal wastes and hazardous landfills; Valutazione della qualita' delle acque profonde in prossimita' di impianti di discarica per rifiuti solidi urbani e per rifiuti pericolosi

Energy Technology Data Exchange (ETDEWEB)

Bellino, M.; Falleni, F.; Forte, T.; Musmeci, L. [Istituto Superiore di Sanita' , Rome (Italy). Lab. di Igiene Ambientale

1999-07-01

The report discusses the impact on ground waters quality in relation to municipal and similar waste landfills and hazardous waste landfills, examined in three landfills of first category and one landfill of second category type C. Analytical results from sampling of ground and leaching waters are reported; from these results it can be deduced that environmental impact is minimum or non-existent, where law criteria for construction and management of landfills are respected. [Italian] Il rapporto esamina l'impatto sulla qualita' delle acque profonde dovuto agli impianti di discarica per rifiuti solidi urbani e assimilabili e per rifiuti pericolosi, rispettivamente di tre discariche controllate di prima categoria ed una di seconda di tipo C. Vengono riportate le risultanze analitiche relative ai campionamenti per la costruzione e gestione delle discariche. L'impatto ambientale e' minimo se non assente.

The influence of disinfectants on mutagenicity and on toxicity of urban waste water; Valutazione di trattamenti di disinfezione di acque reflue urbane mediante test di tossicita' e di mutagenesi

Energy Technology Data Exchange (ETDEWEB)

Monarca, S. [Brescia Univ., Brescia (IT). Dipt. di Medicina Sperimentale e Applicata] [and others

1999-12-01

The aim of the research was to study the influence of disinfectants alternative to chlorine, such as chlorine dioxide, ozone, peracetic acid and UV radiation, have on the formation of mutagenic and toxic compounds in waste water disinfection. Preliminary results are presented and discussed. [Italian] Scopo del lavoro e' stato lo studio dell'azione antimicrobica di diversi disinfettanti su acque reflue urbane dopo trattamento secondario, correlando tale parametro con l'attivita' tossica e genotossica prodotta dalla disinfezione. I risultati vengono presentati e discussi.

Dynamics of the ethanolamine glycerophospholipid remodeling network.

Directory of Open Access Journals (Sweden)

Lu Zhang

Full Text Available Acyl chain remodeling in lipids is a critical biochemical process that plays a central role in disease. However, remodeling remains poorly understood, despite massive increases in lipidomic data. In this work, we determine the dynamic network of ethanolamine glycerophospholipid (PE remodeling, using data from pulse-chase experiments and a novel bioinformatic network inference approach. The model uses a set of ordinary differential equations based on the assumptions that (1 sn1 and sn2 acyl positions are independently remodeled; (2 remodeling reaction rates are constant over time; and (3 acyl donor concentrations are constant. We use a novel fast and accurate two-step algorithm to automatically infer model parameters and their values. This is the first such method applicable to dynamic phospholipid lipidomic data. Our inference procedure closely fits experimental measurements and shows strong cross-validation across six independent experiments with distinct deuterium-labeled PE precursors, demonstrating the validity of our assumptions. In contrast, fits of randomized data or fits using random model parameters are worse. A key outcome is that we are able to robustly distinguish deacylation and reacylation kinetics of individual acyl chain types at the sn1 and sn2 positions, explaining the established prevalence of saturated and unsaturated chains in the respective positions. The present study thus demonstrates that dynamic acyl chain remodeling processes can be reliably determined from dynamic lipidomic data.

Biodiesel from waste cooking oil via base-catalytic and supercritical methanol transesterification

International Nuclear Information System (INIS)

Demirbas, Ayhan

2009-01-01

In this study, waste cooking oil has subjected to transesterification reaction by potassium hydroxide (KOH) catalytic and supercritical methanol methods obtaining for biodiesel. In catalyzed methods, the presence of water has negative effects on the yields of methyl esters. In the catalytic transesterification free fatty acids and water always produce negative effects since the presence of free fatty acids and water causes soap formation, consumes catalyst, and reduces catalyst effectiveness. Free fatty acids in the waste cooking oil are transesterified simultaneously in supercritical methanol method. Since waste cooking oil contains water and free fatty acids, supercritical transesterification offers great advantage to eliminate the pre-treatment and operating costs. The effects of methanol/waste cooking oils ratio, potassium hydroxide concentration and temperature on the biodiesel conversion were investigated

Determination of Methanol Content in Herbal Distillates Produced in Urmia Using Spectrophotometry

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Mohammad Delirrad

2012-05-01

Full Text Available Background: Herbal distillates have been used for many centuries as drinks, flavors, and herbal medicine in Iran, especially in the city of Urmia. Recently, some studies claimed the presence of methanol in different types of herbal distillates. Methanol is a highly toxic compound which can cause acute or chronic toxicity in humans. Acute poisoning with methanol can cause different complications and even death while chronic methanol exposure has a wide range of nonspecific and misleading findings. The main purpose of this study was to determine methanol content in the commonly-used industrial herbal distillates produced in Urmia. Methods: Five samples of six types of most commonly used herbal distillates (peppermint, musk willow, lemon balm, pennyroyal, dill, and rose water were purchased from five active herbal distillates manufacturers in Urmia. All samples were transferred to the laboratory and methanol content of each sample was measured two times according to the standard method of analysis using spectrophotometer. Results: The lowest and highest concentration of methanol were found in rose water (mean=72.4±32.1 ppm and musk willow (mean=278.3±106 ppm samples, respectively. One-way ANOVA showed statistically significant differences among methanol concentrations in the studied herbal distillates (F=60.9, P <0.001. Discussion: Different amounts of methanol were found in herbal distillates and it seems that there are statistically significant differences in methanol concentrations of various types of herbal distillates. Therefore, considering the harmful effects of methanol on human health, further studies are required for determining permitted levels of methanol in herbal distillates.

Methanol Synthesis: Optimal Solution for a Better Efficiency of the Process

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Grazia Leonzio

2018-02-01

Full Text Available In this research, an ANOVA analysis and a response surface methodology are applied to analyze the equilibrium of methanol reaction from pure carbon dioxide and hydrogen. In the ANOVA analysis, carbon monoxide composition in the feed, reaction temperature, recycle and water removal through a zeolite membrane are the analyzed factors. Carbon conversion, methanol yield, methanol productivity and methanol selectivity are the analyzed responses. Results show that main factors have the same effect on responses and a common significant interaction is not present. Carbon monoxide composition and water removal have a positive effect, while temperature and recycle have a negative effect on the system. From central composite design, an optimal solution is found in order to overcome thermodynamic limit: the reactor works with a membrane at lower temperature with carbon monoxide composition in the feed equal to 10 mol % and without recycle. In these conditions, carbon conversion, methanol yield, methanol selectivity, and methanol production are, respectively, higher than 60%, higher than 60%, between 90% and 95% and higher than 0.15 mol/h when considering a feed flow rate of 1 mol/h. A comparison with a traditional reactor is also developed: the membrane reactor ensures to have a carbon conversion higher of the 29% and a methanol yield higher of the 34%. Future researches should evaluate an economic analysis about the optimal solution.

L'impronta idrica di quello che mangiamo

NARCIS (Netherlands)

Bacenetti, J.; Lovarelli, D.; Fiala, M.; Hoekstra, Arjen Ysbert

2015-01-01

È stata recentemente approvata la norma ISO (ISO 14046 Water footprint – requirements and guidelines) per la definizione dell’impronta idrica (Water Footprint) (vedi box). Questo nuovo indicatore di sostenibilità ambientale permette di quantificare il consumo di acqua dolce associato, direttamente o

Economic optimization of heat pump-assisted distillation columns in methanol-water separation

International Nuclear Information System (INIS)

Shahandeh, Hossein; Jafari, Mina; Kasiri, Norollah; Ivakpour, Javad

2015-01-01

Finding efficient alternative to CDiC (Conventional Distillation Column) for methanol-water separation has been an attractive field of study in literature. In this work, five heat pump-assisted schemes are proposed and compared to each other to find the optimal one; (1) VRC (Vapor Recompression Column), (2) external HIDiC (Heat-Integrated Distillation Column), (3) intensified HIDiC with feed preheater, (4) double compressor intensified HIDiC-1, and (5) double compressor intensified HIDiC-2. GA (Genetic Algorithm) is then implemented for optimization of the schemes when TAC (Total Annual Cost) is its objective function. During optimization, two new variables are added for using only appropriate amount of the overhead stream in VRC and double compressor intensified HIDiCs, and another new binary variable is also used for considering feed preheating. Although TAC of the intensified HIDiC with feed preheater is found higher than CDiC by 25.0%, all optimal VRC, external HIDiC, double compressor intensified HIDiCs schemes are reached lower optimal TAC by 3.1%, 27.2%, 24.4%, and 34.2%. Introduced for the first time, the optimal scheme is the double compressor intensified HIDiC-2 with 34.2% TAC saving, 70.4% TEC (Total Energy Consumption) reduction with payback period of 3.30 years. - Highlights: • Study of an industrial distillation unit in methanol-water separation. • Optimization of different heat pump-assisted distillation columns. • Implementation of genetic algorithm during optimization. • Economic and thermodynamic comparisons of optimal results with the industrial case

Methanol, Ethanol and Propanol in EHD liquid bridging

International Nuclear Information System (INIS)

Fuchs, Elmar C; Wexler, Adam D; Agostinho, Luewton L F; Ramek, Michael; Woisetschläger, Jakob

2011-01-01

When a high-voltage direct-current is applied to two beakers filled with water or polar liquid dielectrica, a horizontal bridge forms between the two beakers. In this work such bridges made of methanol, ethanol, 1-propanol and 2-propanol are investigated with polarimetry and thermography. Whereas methanol, ethanol and 1-propanol bridges become warm like a water bridge, a 2-propanol bridge cools down relative to the surroundings. It is shown how the different stability of the primary and secondary alcoholate ions and the resulting small difference in conductivity between 1-propanol and 2-propanol is responsible for this novel effect.

Molecular dynamics simulations to examine structure, energetics, and evaporation/condensation dynamics in small charged clusters of water or methanol containing a single monatomic ion.

Science.gov (United States)

Daub, Christopher D; Cann, Natalie M

2012-11-01

We study small clusters of water or methanol containing a single Ca(2+), Na(+), or Cl(-) ion with classical molecular dynamics simulations, using models that incorporate polarizability via the Drude oscillator framework. Evaporation and condensation of solvent from these clusters is examined in two systems, (1) for isolated clusters initially prepared at different temperatures and (2) those with a surrounding inert (Ar) gas of varying temperature. We examine these clusters over a range of sizes, from almost bare ions up to 40 solvent molecules. We report data on the evaporation and condensation of solvent from the clusters and argue that the observed temperature dependence of evaporation in the smallest clusters demonstrates that the presence of heated gas alone cannot, in most cases, solely account for bare ion production in electrospray ionization (ESI), neglecting the key contribution of the electric field. We also present our findings on the structure and energetics of the clusters as a function of size. Our data agree well with the abundant literature on hydrated ion clusters and offer some novel insight into the structure of methanol and ion clusters, especially those with a Cl(-) anion, where we observe the presence of chain-like structures of methanol molecules. Finally, we provide some data on the reparameterizations necessary to simulate ions in methanol using the separately developed Drude oscillator models for methanol and for ions in water.

Sorption and permeation of solutions of chloride salts, water and methanol in a Nafion membrane

International Nuclear Information System (INIS)

Villaluenga, J.P.G.; Barragan, V.M.; Seoane, B.; Ruiz-Bauza, C.

2006-01-01

The sorption of water-methanol mixtures containing a dissolved chloride salt in a Nafion 117 membrane, and their transport through the membrane under the driving force of a pressure gradient, have been studied. Both type of experiments was performed by using five different salts: lithium chloride, sodium chloride, cesium chloride, magnesium chloride and calcium chloride. It was observed that both the permeation flow through the membrane and the membrane swelling increase significantly with the methanol content of the solutions. These facts are attributed to the increase in wet membrane porosity, which brings about the increase of the mobility of solvents in the membrane, besides the increase of the mobility of the polymer pendant chains. In contrast, the influence of the type of electrolyte on the membrane porosity and permeability is not very important, with the exception of the CsCl solutions, which is probably due to the small hydration ability of the Cs + ion

Characterization of an anionic-exchange membranes for direct methanol alkaline fuel cells

Energy Technology Data Exchange (ETDEWEB)

Abuin, Graciela C. [Centro de Procesos Superficiales, Instituto Nacional de Tecnologia Industrial (INTI), Av. Gral. Paz 5445, B1650KNA, San Martin, Buenos Aires (Argentina); Nonjola, Patrick; Mathe, Mkhulu K. [Council for Scientific and Industrial Research (CSIR), Material Science and Manufacturing, PO Box 395, Brumeria, Pretoria 0001 (South Africa); Franceschini, Esteban A.; Izraelevitch, Federico H.; Corti, Horacio R. [Departamento de Fisica de la Materia Condensada, Comision Nacional de Energia Atomica (CNEA), Av. Gral. Paz 1499, B1650KNA, San Martin, Buenos Aires (Argentina)

2010-06-15

Ammonium quaternized polymers such as poly (arylene ether sulfones) are being developed and studied as candidates of ionomeric materials for application in alkaline fuel cells, due to their low cost and promising electrochemical properties. In this work, a quaternary ammonium polymer was synthesized by chloromethylation of a commercial polysulfone followed by amination process. Quaternized polysulfone membrane properties such us water and water-methanol uptake, electrical conductivity and Young's modulus were evaluated and compared to Nafion 117, commonly employed in direct methanol fuel cells. The anionic polysulfone membrane sorbs more water than Nafion all over the whole range of water activities, but it uptakes much less methanol as compared to Nafion. The specific conductivity of the fully hydrated polysulfone membrane equilibrated with KOH solutions at ambient temperature increases with the KOH concentration, reaching a maximum of 0.083 S cm{sup -1} for 2 M KOH, slightly less conductive than Nafion 117. The elastic modulus of the polysulfone membranes inmersed in water is similar to that reported for Nafion membranes under the same conditions. We concluded that quaternized polysulfone membrane are good candidates as electrolytes in alkaline direct methanol fuel cells. (author)

Effect of cetane improver addition into diesel fuel: Methanol mixtures on performance and emissions at different injection pressures

Directory of Open Access Journals (Sweden)

Candan Feyyaz

2017-01-01

Full Text Available In this study, methanol in ratios of 5-10-15% were incorporated into diesel fuel with the aim of reducing harmful exhaust gasses of Diesel engine, di-tertbutyl peroxide as cetane improver in a ratio of 1% was added into mixture fuels in order to reduce negative effects of methanol on engine performance parameters, and isobutanol of a ratio of 1% was used as additive for preventing phase separation of all mixtures. As results of experiments conducted on a single cylinder and direct injection Diesel engine, methanol caused the increase of NOx emission while reducing CO, HC, CO2, and smoke opacity emissions. It also reduced torque and power values, and increased brake specific fuel consumption values. Cetane improver increased torque and power values slightly compared to methanol-mixed fuels, and reduced brake specific fuel consumption values. It also affected exhaust emission values positively, excluding smoke opacity. Increase of injector injection pressure affected performances of methanol-mixed fuels positively. It also increased injection pressure and NOx emissions, while reducing other exhaust emissions.

Crystal structure of diaphorin methanol monosolvate isolated from Diaphorina citri Kuwayama, the insect vector of citrus greening disease.

Science.gov (United States)

Szebenyi, D Marian; Kriksunov, Irina; Howe, Kevin J; Ramsey, John S; Hall, David G; Heck, Michelle L; Krasnoff, Stuart B

2018-04-01

The title compound C 22 H 39 NO 9 ·CH 3 OH [systematic name: ( S )- N -(( S )-{(2 S ,4 R ,6 R )-6-[( S )-2,3-di-hydroxy-prop-yl]-4-hy-droxy-5,5-di-methyl-tetra-hydro-2 H -pyran-2-yl}(hy-droxy)meth-yl)-2-hy-droxy-2-[(2 R ,5 R ,6 R )-2-meth-oxy-5,6-dimeth-yl-4-methyl-ene-tetra-hydro-2 H -pyran-2-yl]acetamide methanol monosolvate], was isolated from the Asian citrus psyllid, Diaphorina citri Kuwayama, and crystallizes in the space group P 2 1 . ' Candidatus Profftella armatura' a bacterial endosymbiont of D. citri , biosynthesizes diaphorin, which is a hybrid polyketide-nonribosomal peptide comprising two highly substituted tetra-hydro-pyran rings joined by an N -acyl aminal bridge [Nakabachi et al. (2013 ▸). Curr. Biol. 23 , 1478-1484]. The crystal structure of the title compound establishes the complete relative configuration of diaphorin, which agrees at all nine chiral centers with the structure of the methanol monosolvate of the di- p -bromo-benzoate derivative of pederin, a biogenically related compound whose crystal structure was reported previously [Furusaki et al. (1968 ▸). Tetra-hedron Lett. 9 , 6301-6304]. Thus, the absolute configuration of diaphorin is proposed by analogy to that of pederin.

Methanol suppression of trichloroethylene degradation by M. trichosporium

International Nuclear Information System (INIS)

Palumbo, A.V.; Eng, W.

1990-01-01

Biodegradation by methylotrophs has been considered a potential method for in situ remediation, but delivery of sufficient methane could be a problem. Since methanol could be delivered more readily into soil, the authors examined TCE degradation under methane (0.89 M), methanol (1.187 mM), and combined methane (0.89 mM) methanol (1.187 mM) stimulated treatments using M. trichosporium and mixed cultures JS and DT. Degradation of TCE was determined by the summation of radiolabeled CO 2 , water-soluble intermediates, and biomass transformed from 14 C TCE. M. trichosporium degraded 0.36 ± 2.08% (mean ± std dev) of the initial TCe (0.3 mg/l) with methanol stimulation, compared to 9.07 ± 1.04% with methane stimulation. JS and DT cultures degraded 4.34 ± 0.11% on methanol compared to 24.3 ± 1.38% and 34.3 ± 3.0% on methane, respectively. If methanol was added to methane-stimualted cultures, TCE degradation was reduced to 1.08 ± 1.74% for M. trichosporium, and 5.08 ± 0.56% for JS culture. Methanol retarded the rates of methane and oxygen utilization as well. However, methanol-stimulated cultures grew to a greater extent than methane-stimulated cultures with 14 mg/l TCE. Previous workers have shown that methanol suppresses methane monooxygenase, and they suggest this may explain the reduced amount of TCE degraded

THE ROLE OF METHANOL IN THE CRYSTALLIZATION OF TITAN'S PRIMORDIAL OCEAN

International Nuclear Information System (INIS)

Deschamps, Frederic; Mousis, Olivier; Sanchez-Valle, Carmen; Lunine, Jonathan I.

2010-01-01

A key parameter that controls the crystallization of primordial oceans in large icy moons is the presence of anti-freeze compounds, which may have maintained primordial oceans over the age of the solar system. Here we investigate the influence of methanol, a possible anti-freeze candidate, on the crystallization of Titan's primordial ocean. Using a thermodynamic model of the solar nebula and assuming a plausible composition of its initial gas phase, we first calculate the condensation sequence of ices in Saturn's feeding zone, and show that in Titan's building blocks methanol can have a mass fraction of ∼4 wt% relative to water, i.e., methanol can be up to four times more abundant than ammonia. We then combine available data on the phase diagram of the water-methanol system and scaling laws derived from thermal convection to estimate the influence of methanol on the dynamics of the outer ice I shell and on the heat transfer through this layer. For a fraction of methanol consistent with the building blocks composition we determined, the vigor of convection in the ice I shell is strongly reduced. The effect of 5 wt% methanol is equivalent to that of 3 wt% ammonia. Thus, if methanol is present in the primordial ocean of Titan, the crystallization may stop, and a sub-surface ocean may be maintained between the ice I and high-pressure ice layers. A preliminary estimate indicates that the presence of 4 wt% methanol and 1 wt% ammonia may result in an ocean of thickness at least 90 km.

Vapor-liquid equilibrium data for five binary systems of methanol, tert-butylalcohol, tert-butylmethylether and water, and quaternary reactive system producing tert-butylmethylether from methanol and tert-butylalcohol; Metanoru, tert-buchiruarukoru, tert-buchirumechirueteru oyobi mizu wo kumiawaseta 5shu no niseibunkei to metanoru to tert-buchiruarukoru ni yoru eteruka hannokei no taikiatsuka ni okeru kieki heiko deta

Energy Technology Data Exchange (ETDEWEB)

Komatsu, H.; Nakamura, M.; Yamashita, Y.; Hirai, C. [Toyohashi Univ. of Technology (Japan)

1997-11-01

At atmospheric pressure, vapor-liquid equilibrium relationships for five binary systems of methanol-tert-butylalcohol, methanol-tert-butylmethylether, tert-butylalcohol-tert-butylmethylether, water-tert-butylalcohol and water-tert-butylmethylether are observed. The Wilson parameters for the binary systems have been obtained. Comparisons between the Wilson method, The ASOG method and the UNIFAC method are made. Vapor-liquid equilibrium relationships of the quaternary reactive system producing tert-butylmethylether by use of methanol and tert-butylalcohol are also observed, and it is confirmed that the Wilson parameters resulting from the data of binary systems can be used to estimate the vapor-liquid equilibrium data for the quaternary reactive system of methanol-tert-butylalcohol-tert-butylmethylether-water. 6 refs., 7 figs., 5 tabs.

Oxygen sensor equipped engine operation on methanol/gasoline blends and phase separation problems

Energy Technology Data Exchange (ETDEWEB)

Last, A J; Lawson, A; Simmons, E W; Mackay, D; Tsang, M; Maund, G B

1980-01-01

A study was made to address problems related to Canadian utilization of methanol/gasoline blends. These problems are: (1) cold weather operation; (2) water sensitivity to phase separation in winter; (3) vehicle compatibility: fuel/air ratio control, flexibility for vehicle movement outside of areas where methanol might be available. Specifically, the operation of the HydroShear (an in-line hydraulic emulsifier) on the two separated phases of a methanol/gasoline/water blend was examined. Fuel maps, by engine dynamometer testing, were generated using methanol/gasoline blends containing 15% to 65% methanol. The capability of an oxygen sensor, located in the exhaust system, to control the fuel/air ratio was found to be adequate within the 15% to 65% methanol/gasoline blends. A fuel injected Volvo 244DL with lambda-sond emission control and a carburetted Chevrolet Monza with 3-way catalyst closed loop feedback emission control system were the two engines selected for this study.

Temperature of maximum density and excess thermodynamics of aqueous mixtures of methanol

Energy Technology Data Exchange (ETDEWEB)

González-Salgado, D.; Zemánková, K. [Departamento de Física Aplicada, Universidad de Vigo, Campus del Agua, Edificio Manuel Martínez-Risco, E-32004 Ourense (Spain); Noya, E. G.; Lomba, E. [Instituto de Química Física Rocasolano, CSIC, Calle Serrano 119, E-28006 Madrid (Spain)

2016-05-14

In this work, we present a study of representative excess thermodynamic properties of aqueous mixtures of methanol over the complete concentration range, based on extensive computer simulation calculations. In addition to test various existing united atom model potentials, we have developed a new force-field which accurately reproduces the excess thermodynamics of this system. Moreover, we have paid particular attention to the behavior of the temperature of maximum density (TMD) in dilute methanol mixtures. The presence of a temperature of maximum density is one of the essential anomalies exhibited by water. This anomalous behavior is modified in a non-monotonous fashion by the presence of fully miscible solutes that partly disrupt the hydrogen bond network of water, such as methanol (and other short chain alcohols). In order to obtain a better insight into the phenomenology of the changes in the TMD of water induced by small amounts of methanol, we have performed a new series of experimental measurements and computer simulations using various force fields. We observe that none of the force-fields tested capture the non-monotonous concentration dependence of the TMD for highly diluted methanol solutions.

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

Science.gov (United States)

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.

Coadsorbed species explain the mechanism of methanol temperature-desorption on CeO₂(111)

Energy Technology Data Exchange (ETDEWEB)

Sutton, Jonathan E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Overbury, Steven H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Beste, Ariana [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2016-03-24

Here, we have used density functional theory calculations to investigate the temperature-programmed desorption (TPD) of methanol from CeO₂(111). For the first time, low-temperature water formation and high-temperature methanol desorption are explained by our calculations. High coverages of methanol, which correspond to experimental conditions, are required to properly describe these features of the TPD spectrum. We identify a mechanism for the low-temperature formation of water involving the dissociation of two methanol molecules on the same surface O atom and filling of the resulting surface vacancy with one of the methoxy products. After water desorption, methoxy groups are stabilized on the surface and react at higher temperatures to form methanol and formaldehyde by a disproportionation mechanism. Alternatively, the stabilized methoxy groups undergo sequential C–H scission reactions to produce formaldehyde. Calculated energy requirements and methanol/formaldehyde selectivity agree with the experimental data.

Renewable hydrogen utilisation for the production of methanol

International Nuclear Information System (INIS)

Galindo Cifre, P.; Badr, O.

2007-01-01

Electrolytic hydrogen production is an efficient way of storing renewable energy generated electricity and securing the contribution of renewables in the future electricity supply. The use of this hydrogen for the production of methanol results in a liquid fuel that can be utilised directly with minor changes in the existing infrastructure. To utilise the renewable generated hydrogen for production of renewable methanol, a sustainable carbon source is needed. This carbon can be provided by biomass or CO 2 in the flue gases of fossil fuel-fired power stations, cement factories, fermentation processes and water purification plants. Methanol production pathways via biomass gasification and CO 2 recovery from the flue gasses of a fossil fuel-fired power station have been reviewed in this study. The cost of methanol production from biomass was found to lie in the range of 300-400 EUR/tonne of methanol, and the production cost of CO 2 based methanol was between 500 and 600 EUR/tonne. Despite the higher production costs compared with methanol produced by conventional natural gas reforming (i.e. 100-200 EUR/tonne, aided by the low current price of natural gas), these new processes incorporate environmentally beneficial aspects that have to be taken into account. (author)

Performance and endurance of a high temperature PEM fuel cell operated on methanol reformate

DEFF Research Database (Denmark)

Araya, Samuel Simon; Grigoras, Ionela; Zhou, Fan

2014-01-01

This paper analyzes the effects of methanol and water vapor on the performance of a high temperature proton exchange membrane fuel cell (HT-PEMFC) at varying temperatures, ranging from 140 °C to 180 °C. For the study, a H3PO4 – doped polybenzimidazole (PBI) – based membrane electrode assembly (MEA......) of 45 cm2 active surface area from BASF was employed. The study showed overall negligible effects of methanol-water vapor mixture slips on performance, even at relatively low simulated steam methanol reforming conversion of 90%, which corresponds to 3% methanol vapor by volume in the anode gas feed....... Temperature on the other hand has significant impact on the performance of an HT-PEMFC. To assess the effects of methanol-water vapor mixture alone, CO2 and CO are not considered in these tests. The analysis is based on polarization curves and impedance spectra registered for all the test points. After...

Hepato-Protective Potential of Methanol Extract of Leaf of Ziziphus ...

African Journals Online (AJOL)

Objective: The study was carried out to evaluate the hepatoprotective potential of the methanol leaf extract of Ziziphus mucronata (ZMLM). Method: The extract was prepared by soaking in 70% methanol/water and rotary evaporation. The phenol content of extract was then estimated. Twenty five adult male Sprague dawley ...

Heat and mass transfer effects in a direct methanol fuel cell: A 1D model

Energy Technology Data Exchange (ETDEWEB)

Oliveira, V.B.; Falcao, D.S.; Pinto, A.M.F.R. [Centro de Estudos de Fenomenos de Transporte, Departamento de Eng. Quimica, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto (Portugal); Rangel, C.M. [INETI - Unidade de Electroquimica e Materiais, Paco do Lumiar, 22,1649-038 (Portugal)

2008-07-15

Models are a fundamental tool for the design process of fuel cells and fuel cell systems. In this work, a steady-state, one-dimensional model accounting for coupled heat and mass transfer, along with the electrochemical reactions occurring in the DMFC, is presented. The model output is the temperature profile through the cell and the water balance and methanol crossover between the anode and the cathode. The model predicts the correct trends for the influence of current density and methanol feed concentration on both methanol and water crossover. The model estimates the net water transfer coefficient through the membrane, {alpha}, a very important parameter to describe water management in the DMFC. Suitable operating ranges can be set up for different MEA structures maintaining the crossover of methanol and water within acceptable levels. The model is rapidly implemented and is therefore suitable for inclusion in real-time system level DMFC calculations. (author)

The deep-subsurface sulfate reducer Desulfotomaculum kuznetsovii employs two methanol-degrading pathways.

Science.gov (United States)

Sousa, Diana Z; Visser, Michael; van Gelder, Antonie H; Boeren, Sjef; Pieterse, Mervin M; Pinkse, Martijn W H; Verhaert, Peter D E M; Vogt, Carsten; Franke, Steffi; Kümmel, Steffen; Stams, Alfons J M

2018-01-16

Methanol is generally metabolized through a pathway initiated by a cobalamine-containing methanol methyltransferase by anaerobic methylotrophs (such as methanogens and acetogens), or through oxidation to formaldehyde using a methanol dehydrogenase by aerobes. Methanol is an important substrate in deep-subsurface environments, where thermophilic sulfate-reducing bacteria of the genus Desulfotomaculum have key roles. Here, we study the methanol metabolism of Desulfotomaculum kuznetsovii strain 17 T , isolated from a 3000-m deep geothermal water reservoir. We use proteomics to analyze cells grown with methanol and sulfate in the presence and absence of cobalt and vitamin B12. The results indicate the presence of two methanol-degrading pathways in D. kuznetsovii, a cobalt-dependent methanol methyltransferase and a cobalt-independent methanol dehydrogenase, which is further confirmed by stable isotope fractionation. This is the first report of a microorganism utilizing two distinct methanol conversion pathways. We hypothesize that this gives D. kuznetsovii a competitive advantage in its natural environment.

A small mono-polar direct methanol fuel cell stack with passive operation

Science.gov (United States)

Chan, Y. H.; Zhao, T. S.; Chen, R.; Xu, C.

A passive direct methanol fuel cell (DMFC) stack that consists of six unit cells was designed, fabricated, and tested. The stack was tested with different methanol concentrations under ambient conditions. It was found that the stack performance increased when the methanol concentration inside the fuel tank was increased from 2.0 to 6.0 M. The improved performance is primarily due to the increased cell temperature as a result of the exothermic reaction between the permeated methanol and oxygen on the cathode. Moreover, the increased cell temperature enhanced the water evaporation rate on the air-breathing cathode, which significantly reduced water flooding on the cathode and further improved the stack performance. This passive DMFC stack, providing 350 mW at 1.8 V, was successfully applied to power a seagull display kit. The seagull display kit can continuously run for about 4 h on a single charge of 25 cm 3 4.0-M methanol solution.

Performance comparison of a silica gel-water and activated carbon-methanol two beds adsorption chillers

Directory of Open Access Journals (Sweden)

Szelągowski Adam

2017-01-01

Full Text Available The aim of the study is to compare the efficiency of adsorption refrigerating equipment working with different working pairs. Adsorption cooling devices can operate with a relatively low temperature of heat sources while consuming only a small amount of electricity for the operation of auxiliary equipment. Refrigerants used in adsorption devices are substances that do not have a negative impact on the environment. All that makes that adsorption refrigeration seems to be a good solution for utilizing renewable and waste heat sources for cold production. To carry out the experiment the adsorption cooling device has been developed and researched in Institute of Heat Engineering at Warsaw University of Technology. The test bench consisted of two cylindrical adsorbers, condenser, evaporator, oil heater and two oil coolers. In order to perform the correct action it has been developed and implemented special control algorithm device, allowed to keep the temperature in the evaporator at a preset level. The unit tested for two sorption pairs: activated carbon – methanol, and silica gel – water. For activated carbon - methanol working pair it was obtained energy efficiency rating (EER equals to 0.14 and specific cooling power (SPC of 16 W/kg. For silica gel - water EER of refrigeration unit was 0.25 and SPC was equal to 208 W/kg.

Absorber design in sour natural gas treatment plants: Impact of process variables on operation and economics = Absorberentwurf für Anlagen zur Behandlung von sauren Erdgasen: Einfluss Prozessparameter auf Betriebsführung und Prozesswirtschaftlichkeit

NARCIS (Netherlands)

Blauwhoff, P.M.M.; Kamphuis, B.; van Swaaij, Willibrordus Petrus Maria; Westerterp, K.R.

1985-01-01

Two models of absorber have been developed which describe the absorption of H2S and CO2 from natural gases by aqueous di-isopropanolamine (DIPA) or methyl-di-ethanolamine (MDEA) solutions. In these models mass transfer, reaction and equilibrium processes as they prevail in conventional tray

Liquid densities and excess molar volumes for (ionic liquids + methanol + water) ternary system at atmospheric pressure and at various temperatures

Energy Technology Data Exchange (ETDEWEB)

Deenadayalu, Nirmala [Department of Chemistry, Durban University of Technology, Steve Biko Campus, P.O. Box 1334, Durban, KwaZulu-Natal 4001 (South Africa)], E-mail: NirmalaD@dut.ac.za; Kumar, Satish; Bhujrajh, Pravena [Department of Chemistry, Durban University of Technology, Steve Biko Campus, P.O. Box 1334, Durban, KwaZulu-Natal 4001 (South Africa)

2007-09-15

Excess molar volumes, V{sub m}{sup E} have been evaluated from density measurements over the entire composition range for ternary liquid system of ionic liquid (1-ethyl-3-methyl-imidazolium diethylenglycol monomethylether sulphate {l_brace}[EMIM][CH{sub 3}(OCH{sub 2}CH{sub 2}){sub 2}OSO{sub 3}]) (1) + methanol (2) + water (3){r_brace} at T = (298.15, 303.15, and 313.15) K. A vibrating tube densimeter was used for these measurements at atmospheric pressure. The V{sub m}{sup E} values were found to be negative at T = (298.15 and 303.15) K. For {l_brace}[EMIM][CH{sub 3}(OCH{sub 2}CH{sub 2}){sub 2}OSO{sub 3}] (1) + methanol (2) + water (3){r_brace} at T = 313.15 K the V{sub m}{sup E} values become positive at higher mole fraction of ionic liquid and at a corresponding decrease in mole fraction of water. All the experimental data were fitted with the Redlich-Kister equation. The results have also been analysed in term of graph theoretical approach.

Determination of Thermodynamical Data of Calcium Hydroxichloride Détermination des données thermodynamiques de l'hydroxychlorure de calcium

Directory of Open Access Journals (Sweden)

Allal K. M.

2006-12-01

Full Text Available The reaction of hydrochloric acid with dry alkaline sorbents such as hydrated lime in the incineration units leads to the formation of not only calcium chloride but calcium hydroxichloride as well. A thermodynamic study of the chemical reactions involved in the dechlorination process is required in order to show if such a product is theoretically possible to be formed. However, the data of CaCIOH necessary to carry out such a study are not available in the literature. Hence, a method of predicting these data is developed in the present work. Predicted values of Gibbs energy and entropy of formation of CaCIOH at different temperatures are compared to values calculated by Mostafa's model and satisfactory results were obtained. La réaction de l'acide chlorhydrique avec des adsorbants alcalins tels que la chaux au niveau de stations d'incinération entraîne la formation de chlorure ainsi que de l'hydroxychlorure de calcium. Une étude thermodynamique des différentes réactions mises en jeu dans le procédé de déchloruration serait nécessaire, afin de montrer qu'un tel produit serait théoriquement susceptible d'être formé. Cependant, les données thermodynamiques de CaCIOH permettant de mener à bien une telle étude ne sont pas disponibles dans la littérature. Par conséquent, une méthode permettant de prédire ces données a été développée dans ce présent travail. Des valeurs d'énergie de Gibbs et d'entropie de formation de CaCIOH prédites par cette méthode à différentes températures ont été comparées à celles déterminées à l'aide du modèle de Mostafa, et des résultats satisfaisants ont été obtenus.

Electro-activity of cobalt and nickel complexes for the reduction of protons into di-hydrogen. Application to PEM water electrolysis

International Nuclear Information System (INIS)

Pantani, O.; Anxolabehere, E.; Aukauloo, A.; Millet, P.

2006-01-01

Proton exchange membrane (PEM) water electrolysis is a safe and efficient way to perform water splitting into di-hydrogen and di-oxygen. In a PEM water electrolyser, platinum is commonly used as electro-catalyst on the cathodic side of the cells, mostly because of its efficiency for hydrogen evolution. But for cost considerations, there is a need to find alternative low-cost electrocatalysts. Molecular chemistry offers the possibility of synthesizing new compounds for this purpose, such as transition metal complexes. Results obtained with nickel- and cobalt-oximes compounds are presented in this paper. They have been chemically (1H NMR, EPR) and electrochemically (voltametry, spectro-electrochemistry) characterized. Their ability to electrochemically reduce protons into di-hydrogen when they are either dissolved in solution or immobilized at the surface of a solid electrode is discussed. (authors)

Study on the water flooding in the cathode of direct methanol fuel cells.

Science.gov (United States)

Im, Hun Suk; Kim, Sang-Kyung; Lim, Seongyop; Peck, Dong-Hyun; Jung, Doohwan; Hong, Won Hi

2011-07-01

Water flooding phenomena in the cathode of direct methanol fuel cells were analyzed by using electrochemical impedance spectroscopy. Two kinds of commercial gas diffusion layers with different PTFE contents of 5 wt% (GDL A5) and 20 wt% (GDL B20) were used to investigate the water flooding under various operating conditions. Water flooding was divided into two types: catalyst flooding and backing flooding. The cathode impedance spectra of each gas diffusion layer was obtained and compared under the same conditions. The diameter of the capacitive semicircle became larger with increasing current density for both, and this increase was greater for GDL B20 than GDL A5. Catalyst flooding is dominant and backing flooding is negligible when the air flow rate is high and current density is low. An equivalent model was suggested and fitted to the experimental data. Parameters for catalyst flooding and backing flooding were individually obtained. The capacitance of the catalyst layer decreases as the air flow rate decreases when the catalyst flooding is dominant.

In vitro antibacterial activity of methanol and water extracts of adiantum capillus veneris and tagetes patula against multidrug resistant bacterial strains

International Nuclear Information System (INIS)

Hussain, M.M.; Ahmad, B.; Bashid, E.; Hashim, S.

2014-01-01

The aim of present study was to screen the antimicrobial activities of extracts of leaves and stems of Adiantum capillus veneris and Tagetes patula against multidrug-resistant (MDR) bacterial strains. Extracts from the leaves and stems of these plants were extracted with methanol and water and tested for their antibacterial activity by disc diffusion method against ten MDR bacterial strains i.e., Citrobacter freundii, Escherichia coli, Providencia, Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae, Proteus vulgaris, Salmonella typhi, Shigella and Vibrio cholerae. Leaves methanol extract (LME) of Adiantum showed maximum Zone of Inhibition (ZI) against Providencia, Klebsiella pneumoniae, Shigella, Vibrio cholerae, Staphylococcus aureus, Proteus vulgaris and Salmonella typhi, whereas its stem methanol extract (SME) was very active against Escherichia coli, Klebsiella pneumoniae and Salmonella typhi. Similarly LME of Tagetes showed highest ZI against Escherichia coli and Vibrio cholerae while SME showed highest ZI to Escherichia coli, Vibrio cholerae, Providencia, Shigella and Klebsiella pneumoniae. Leaves water extract (LWE) of Adiantum was very active against all ten bacterial strains while its stem water extract (SWE) showed maximum ZI against Escherichia coli, Klebsiella pneumoniae and Salmonella typhi, Shigella, Proteus vulgaris and Providencia. LWE of Tagetes was only active against Vibrio cholerae whereas SWE was very active against Salmonella typhi and active against P. vulgaris, Citrobacter freundii and Vibrio cholerae. It was concluded from this study that extracts of both Adiantum and Tagetes have prominent activities against most of the MDR bacterial strains and needs further studies for utmost benefits. (author)

Optimization of HPLC method for the isolation of Hypericum perforatum L. methanol extract

Directory of Open Access Journals (Sweden)

Stamenković, J.

2013-12-01

Full Text Available St. John's Wort (Hypericum perforatum L. is one of the most studied plant species in the family Hypericaceae. The aim of this study was the identification of the constituents of methanol extract of H. perforatum and optimization of conditions for their isolation. The main components of the methanol extract were isolated on preparative ZORBAX Eclipse XDB C18 column with solvent system consisting of methanol and 1x10-2 M ammonium acetate in water. Constituents of the extract were identified by comparing their retention times with the retention times of the standards, with the literature data and the UV spectra. By varying the conditions of chromatography, the optimal conditions for isolation of the methanol extract constituents were determined: mobile phase consisting of methanol and 1x10-2 M ammonium acetate in water in ratio 1 : 1, sample concentration 100 mg/mL, sample volume 30 µL, flow 2 mL/min. Under these conditions 7 components of the methanol extract were isolated.

Abiotic and biotic control of methanol exchanges in a temperate mixed forest

Science.gov (United States)

Laffineur, Q.; Aubinet, M.; Schoon, N.; Amelynck, C.; Müller, J.-F.; Dewulf, J.; van Langenhove, H.; Steppe, K.; Heinesch, B.

2012-01-01

Methanol exchanges over a mixed temperate forest in the Belgian Ardennes were measured for more than one vegetation season using disjunct eddy-covariance by a mass scanning technique and Proton Transfer Reaction Mass Spectrometry (PTR-MS). Half-hourly methanol fluxes were measured in the range of -0.6 μg m-2 s-1 to 0.6 μg m-2 s-1, and net daily methanol fluxes were generally negative in summer and autumn and positive in spring. On average, the negative fluxes dominated (i.e. the site behaved as a net sink), in contrast to what had been found in previous studies. An original model describing the adsorption/desorption of methanol in water films present in the forest ecosystem and the methanol degradation process was developed. Its calibration, based on field measurements, predicted a mean methanol degradation rate of -0.0074 μg m-2 s-1 and a half lifetime for methanol in water films of 57.4 h. Biogenic emissions dominated the exchange only in spring, with a standard emission factor of 0.76 μg m-2 s-1. The great ability of the model to reproduce the long-term evolution, as well as the diurnal variation of the fluxes, suggests that the adsorption/desorption and degradation processes play an important role in the global methanol budget. This result underlines the need to conduct long-term measurements in order to accurately capture these processes and to better estimate methanol fluxes at the ecosystem scale.

Fate of methanol spills into rivers of varying geometry

International Nuclear Information System (INIS)

Jamali, M.; Lawrence, G.A.; Maloney, K.

2002-01-01

This paper describes the results of a study of potential environmental impacts of methanol releases into rivers. A number of hypothetical scenarios are defined, and dispersion of methanol in the selected rivers is investigated using a riverine dispersion-biodegradation model. The downstream variability of river flow and hydraulic geometry due to merging tributaries are included in the model. The model results are presented, and comparison is made with proposed allowable concentrations. An interesting finding is that the river variation has considerable effect on concentration distribution of methanol in the most critical scenario. A sensitivity analysis is made on the key modeling parameters such as the dispersion coefficient and the biodegradation rate. An analysis illustrating when water intake systems should potentially be shutdown in the event of a methanol release is also presented. In general, it is found the human health risks associated with the accidental release of methanol into riverine environments are low. (author)

Escherichia coli. A sanitary methodology for faecal water pollution tests; Escherichia coli nelle acque. Significato sanitario e metodologie di analisi

Energy Technology Data Exchange (ETDEWEB)

Bonadonna, L. [Istituto Superiore di Sanita' , Rome (Italy)

2001-02-01

Among the traditional indictors of faecal water pollution, Escherichia coli has shown to fit better with the definition of indicator organism. Till now its recovery has been time-consuming and needs confirmation tests. In this report more rapid and direct methods, based on enzymatic reactions, are presented. [Italian] Per talune peculiari caratteristiche, Escherichia coli sembra meglio soddisfare i requisiti insiti nella definizione di organismo indicatore, rispetto ai tradizionali indicatori di contaminazione fecale dell'acqua. Finora, i substrati disponibili per il suo rilevamento necessitano tutti di almeno una prova di conferma. Di qui l'esigenza di indicare metodi di rilevamento a riposta piu' rapida, anche in relazione all'inserimento, nelle piu' recenti normative nazionali ed europee, del microrganismo tra i parametri microbiologici da ricercare.

Effects of concentration, temperature and solvent composition on density and apparent molar volume of the binary mixtures of cationic-anionic surfactants in methanol-water mixed solvent media.

Science.gov (United States)

Bhattarai, Ajaya; Chatterjee, Sujeet Kumar; Niraula, Tulasi Prasad

2013-01-01

The accurate measurements on density of the binary mixtures of cetyltrimethylammonium bromide and sodium dodecyl sulphate in pure water and in methanol(1) + water (2) mixed solvent media containing (0.10, 0.20, and 0.30) volume fractions of methanol at 308.15, 318.15, and 323.15 K are reported. The concentrations are varied from (0.03 to 0.12) mol.l(-1) of sodium dodecyl sulphate in presence of ~ 5.0×10(-4) mol.l(-1) cetyltrimethylammonium bromide. The results showed almost increase in the densities with increasing surfactant mixture concentration, also the densities are found to decrease with increasing temperature over the entire concentration range, investigated in a given mixed solvent medium and these values are found to decrease with increasing methanol content in the solvent composition. The concentration dependence of the apparent molar volumes appear to be negligible over the entire concentration range, investigated in a given mixed solvent medium and the apparent molar volumes increase with increasing temperature and are found to decrease with increasing methanol content in the solvent composition.

1995 world methanol conference

International Nuclear Information System (INIS)

Anon.

1995-01-01

The 20 papers contained in this volume deal with the global markets for methanol, the production of MTBE, integrating methanol production into a coal-to-SNG complex, production of methanol from natural gas, catalysts for methanol production from various synthesis gases, combined cycle power plants using methanol as fuel, and economics of the methanol industry. All papers have been processed for inclusion on the data base

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

Science.gov (United States)

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.

Comparison between two methods of methanol production from carbon dioxide

International Nuclear Information System (INIS)

Anicic, B.; Trop, P.; Goricanec, D.

2014-01-01

Over recent years there has been a significant increase in the amount of technology contributing to lower emissions of carbon dioxide. The aim of this paper is to provide a comparison between two technologies for methanol production, both of which use carbon dioxide and hydrogen as initial raw materials. The first methanol production technology includes direct synthesis of methanol from CO 2 , and the second has two steps. During the first step CO 2 is converted into CO via RWGS (reverse water gas shift) reaction, and methanol is produced during the second step. A comparison between these two methods was achieved in terms of economical and energy-efficiency bases. The price of electricity had the greatest impact from the economical point of view as hydrogen is produced via the electrolysis of water. Furthermore, both the cost of CO 2 capture and the amounts of carbon taxes were taken into consideration. Energy-efficiency comparison is based on cold gas efficiency, while economic feasibility is compared using net present value. Even though the mentioned processes are similar, it was shown that direct methanol synthesis has higher energy and economic efficiency. - Highlights: • We compared two methods for methanol production. • Process schemes for both, direct synthesis and two-step synthesis, are described. • Direct synthesis has higher economical and energy efficiency

Separation of benzene from mixtures with water, methanol, ethanol, and acetone: highlighting hydrogen bonding and molecular clustering influences in CuBTC

NARCIS (Netherlands)

Gutiérrez-Sevillano, J.J.; Calero, S.; Krishna, R.

2015-01-01

Configurational-bias Monte Carlo (CBMC) simulations are used to establish the potential of CuBTC for separation of water/benzene, methanol/benzene, ethanol/benzene, and acetone/benzene mixtures. For operations under pore saturation conditions, the separations are in favor of molecules that partner

Resonant ion-dip infrared spectroscopy of benzene-(water)n-(methanol)m clusters with n+m=4, 5

International Nuclear Information System (INIS)

Hagemeister, F.C.; Gruenloh, C.J.; Zwier, T.S.

1998-01-01

Resonant two-photon ionization and resonant ion-dip infrared (RIDIR) spectra of benzene-(water) n -(methanol) m clusters (hereafter shortened to BW n M m ) have been recorded for a total of seven clusters with n+m=4 and 5. The infrared spectra in the OH and CH stretch regions show absorptions characteristic of H-bonded W n M m clusters which are bound to benzene by a π H-bond involving a dangling OH on the W n M m sub-unit. Density functional theory (DFT) calculations identify a number of conformational isomers in the n+m=4 series which meet the general criteria imposed by the experimental spectra. The structures, binding energies, harmonic vibrational frequencies, and infrared intensities for these isomers have been calculated for comparison with experiment. Based on the calculations, tentative assignments of several of the observed species are given. The calculations uncover the fact that complexation of benzene to the cyclic water tetramer imposes much the same perturbations on the cycle as substitution of methanol for water. In particular, the single-donor OH stretch spectra of W n M m and BW n+1 M m-1 are calculated to be virtually identical to one another. The comparison of experiment and theory for this series of cyclic structures is used to assess the strengths and limitations of the calculations at the DFT Becke3LYP/6-31+G * level of theory. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

Molar ratios of therapeutic water-soluble phenothiazine⋅water-insoluble phospholipid adducts reveal a Fibonacci correlation and a putative link for structure–activity relationships

DEFF Research Database (Denmark)

Keyzer, Hendrik; Fey, S. J.; Thornton, Barry

2015-01-01

1,2diacyl-sn-glycero-3-phospholipids (PL) with even-numbered symmetric saturated diacyl chains with the headgroups choline (PC), glycerol (PG), serine (PS), ethanolamine (PE), phosphatidic acid (PA). We observed water soluble products with replicable molar ratios (MR) that could be divided into two...

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

Science.gov (United States)

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.

Photoreduction of carbon dioxide and water into formaldehyde and methanol on semiconductor materials

Energy Technology Data Exchange (ETDEWEB)

Aurian-Blajeni, B; Halmann, M; Manassen, J

1980-01-01

Heterogeneous photoassisted reduction of aqueous carbon dioxide was achieved using semiconductor powders, with either high-pressure Hg-lamps or sunlight as energy sources. The products were methanol, formaldehyde and methane. The reaction was carried out either as a gas-solid process, by passing carbon dioxide and water vapor over illuminated semiconductor surfaces, or as a liquid-solid reaction, by illuminating aqueous suspensions of semiconductor powders through which carbon dioxide was bubbled. Best results, under illumination by Hg-lamps, were obtained with aqueous suspensions of strontium titanate, SrTiO3, tungsten oxide, WO3, and titanium oxide, TiO2, resulting in absorbed energy conversion efficiencies of 6, 5.9 and 1.2 per cent, respectively.

Formation of carbonyl compounds in radiolysis of ethylene glycol in methanol

International Nuclear Information System (INIS)

Bezborodova, S.G.; Vetrov, V.S.; Kalyazin, E.P.; Korolev, V.M.; Salamatov, I.I.

1977-01-01

Radiolysis of diluted solutions of ethylene glycol has been investigated. It is shown that acetaldehyde, glycol aldehyde and formaldehyde are the main products of radiolysis of methanol solutions of ethylene glycol. Acetaldehyde and glycol aldehyde yields increase in radiolysis of methanol solutions of ethylene glycol with an increase of the original concentration of ethylene glycol and a temperature rise of radiolysis. Formaldehyde yields increase with the ethylene glycol concentration but decrease with a temperature rise (the formation of formaldehyde from methanol is taken into account). A mechanism of radiation-chemical transformations of ethylene glycol in methanol is explained. It is concluded that the main directions of ethylene glycol decomposition, detected in water solutions of ethylene glycol, are also realized in methanol solutions. However, a role of different directions of decomposition depends on the medium

Crystal structure of trans-N,N′-bis(3,5-di-tert-butyl-2-hydroxyphenyloxamide methanol monosolvate

Directory of Open Access Journals (Sweden)

Miguel-Ángel Velázquez-Carmona

2016-07-01

Full Text Available The here crystallized oxamide was previously characterized as an unsolvated species [Jímenez-Pérez et al. (2000. J. Organomet. Chem. 614–615, 283–293], and is now reported with methanol as a solvent of crystallization, C30H44N2O4·CH3OH, in a different space group. The introduction of the solvent influences neither the molecular symmetry of the oxamide, which remains centrosymmetric, nor the molecular conformation. However, the unsolvated molecule crystallized as an ordered system, while many parts of the solvated crystal are disordered. The hydroxy group in the oxamide is disordered over two chemically equivalent positions, with occupancies 0.696 (4:0.304 (4; one tert-butyl group is disordered by rotation about the C—C bond, and was modelled with three sites for each methyl group, each one with occupancy 1/3. Finally, the methanol solvent, which lies on a twofold axis, is disordered by symmetry. The disorder affecting hydroxy groups and the solvent of crystallization allows the formation of numerous supramolecular motifs using four hydrogen bonds, with N—H and O—H groups as donors and the oxamide and methanol molecule as acceptors.

Nitrates in ground water pollution; Inquinamento da nitrati in zona di ricarica delle falde: la provincia di Treviso in destra Piave

Energy Technology Data Exchange (ETDEWEB)

Vendrame, G. [Regione del Veneto, Venice (Italy). Dir. per la Tutela dell' Ambiente; Ostoich, M.; Aurighi, M.

2000-06-01

In this paper the results of a series of analysis about the parameter nitrate are presented. They were made on samples of groundwater from wells located in a sector of the Veneto plain (in the hydrographic right of the Piave river - western district of Treviso, Italy) in the recharge area. The aim is to characterize sites with the greatest problems with nitrate pollution and to understand the causes with the assessment of pollution loads, for a correct evaluation of the phenomenon for the definition of actions to produce a reversal of trend, referring in particular to the new Italian provisions on water quality. [Italian] L'articolo analizza i dati relativi all'inquinamento da nitrati in zona di discarica delle falde nella provincia di Treviso, lungo la riva destra del Piave.

The (p, ρ, T) of (methanol + benzene) and (methanol + ethylbenzene)

International Nuclear Information System (INIS)

Naziev, Yashar M.; Shahverdiyev, Astan N.; Hasanov, Vaqif H.

2005-01-01

The (p, ρ, T) of methanol, ethylbenzene and (methanol + benzene) and (methanol + ethylbenzene) at temperatures between (290 and 500) K and pressures in the range (0.1 to 60) MPa have been measured with a magnetic suspension densimeter with an uncertainty of ±0.1%. Our measurements with methanol deviate from the literature values by less than 0.2%. The (p, ρ, T) measurements were fitted with experimental uncertainties by an empirical equation. The temperature and mole fraction dependence of the coefficients of the equation of state are presented

China's growing methanol economy and its implications for energy and the environment

International Nuclear Information System (INIS)

Yang, Chi-Jen; Jackson, Robert B.

2012-01-01

For more than a decade, Nobel laureate George Olah and coworkers have advocated the Methanol Economy – replacing petroleum-based fuels and chemicals with methanol and methanol-derivatives – as a path to sustainable development. A first step to this vision appears to be occurring in China. In the past five years, China has quickly built an industry of coal-based methanol and dimethyl ether (DME) that is competitive in price with petroleum-based fuels. Methanol fuels offer many advantages, including a high octane rating and cleaner-burning properties than gasoline. Methanol also has some disadvantages. A coal-based Methanol Economy could enhance water shortages in China, increase net carbon dioxide emissions, and add volatility to regional and global coal prices. China's rapidly expanding Methanol Economy provides an interesting experiment for what could happen elsewhere if methanol is widely adopted, as proposed by Olah and researchers before him. - Highlights: ► China is quickly building a coal-based chemical industry. ► Methanol has become a significant automotive fuel and chemical feedstock in China. ► Coal-based methanol could provide a domestic alternative to imported oil. ► It, however, increases greenhouse gas emissions, and can cause other problems.

The validity of the potential model in predicting the structural, dynamical, thermodynamic properties of the unary and binary mixture of water-alcohol: Methanol-water case

Science.gov (United States)

Obeidat, Abdalla; Abu-Ghazleh, Hind

2018-06-01

Two intermolecular potential models of methanol (TraPPE-UA and OPLS-AA) have been used in order to examine their validity in reproducing the selected structural, dynamical, and thermodynamic properties in the unary and binary systems. These two models are combined with two water models (SPC/E and TIP4P). The temperature dependence of density, surface tension, diffusion and structural properties for the unary system has been computed over specific range of temperatures (200-300K). The very good performance of the TraPPE-UA potential model in predicting surface tension, diffusion, structure, and density of the unary system led us to examine its accuracy and performance in its aqueous solution. In the binary system the same properties were examined, using different mole fractions of methanol. The TraPPE-UA model combined with TIP4P-water shows a very good agreement with the experimental results for density and surface tension properties; whereas the OPLS-AA combined with SPCE-water shows a very agreement with experimental results regarding the diffusion coefficients. Two different approaches have been used in calculating the diffusion coefficient in the mixture, namely the Einstein equation (EE) and Green-Kubo (GK) method. Our results show the advantageous of applying GK over EE in reproducing the experimental results and in saving computer time.

Deciphering Periodic Methanol Masers

Science.gov (United States)

Stecklum, Bringfried; Caratti o Garatti, Alessio; Henning, Thomas; Hodapp, Klaus; Hopp, Ulrich; Kraus, Alex; Linz, Hendrik; Sanna, Alberto; Sobolev, Andrej; Wolf, Verena

2018-05-01

Impressive progress has been made in recent years on massive star formation, yet the involved high optical depths even at submm/mm wavelengths make it difficult to reveal its details. Recently, accretion bursts of massive YSOs have been identified to cause flares of Class II methanol masers (methanol masers for short) due to enhanced mid-IR pumping. This opens a new window to protostellar accretion variability, and implies that periodic methanol masers hint at cyclic accretion. Pinning down the cause of the periodicity requires joint IR and radio monitoring. We derived the first IR light curve of a periodic maser host from NEOWISE data. The source, G107.298+5.639, is an intermediate-mass YSO hosting methanol and water masers which flare every 34.5 days. Our recent joint K-band and radio observations yielded first but marginal evidence for a phase lag between the rise of IR and maser emission, respectively, and revealed that both NEOWISE and K-band light curves are strongly affected by the light echo from the ambient dust. Both the superior resolution of IRAC over NEOWISE and the longer wavelengths compared to our ground-based imaging are required to inhibit the distractive contamination by the light echo. Thus, we ask for IRAC monitoring of G107 to cover one flare cycle, in tandem with 100-m Effelsberg and 2-m Wendelstein radio and NIR observations to obtain the first high-quality synoptic measurements of this kind of sources. The IR-maser phase lag, the intrinsic shape of the IR light curves and their possible color variation during the cycle allow us to constrain models for the periodic maser excitation. Since methanol masers are signposts of intermediate-mass and massive YSOs, deciphering their variability offers a clue to the dynamics of the accretion-mediated growth of massive stars and their feedback onto the immediate natal environment. The Spitzer light curve of such a maser-hosting YSO would be a legacy science product of the mission.

Heat transfer and pressure drop studies of TiO2/DI water nanofluids in helically corrugated tubes using spiraled rod inserts

Science.gov (United States)

Anbu, S.; Venkatachalapathy, S.; Suresh, S.

2018-05-01

An experimental study on the convective heat transfer and friction factor characteristics of TiO2/DI water nanofluids in uniformly heated plain and helically corrugated tubes (HCT) with and without spiraled rod inserts (SRI) under laminar flow regime is presented in this paper. TiO2 nanoparticles with an average size of 32 nm are dispersed in deionized (DI) water to form stable suspensions containing 0.1, 0.15, 0.2, and 0.25% volume concentrations of nanoparticles. It is found that the inclusion of nanoparticles to DI water ameliorated Nusselt number which increased with nanoparticles concentration upto 0.2%. Two spiraled rod inserts made of copper with different pitches (pi = 50 mm and 30 mm) are inserted in both plain and corrugated tubes and it is found that the addition of these inserts increased the Nusselt number substantially. For Helically corrugated tube with lower pitch and maximum height of corrugation (pc = 8 mm, hc = 1 mm) with 0.2% volume concentration of nanoparticles, a maximum enhancement of 15% in Nusselt number is found without insert and with insert having lower pitch (pi = 30 mm) the enhancement is 34% when compared to DI water in plain tube. The results on friction factor show a maximum penalty of about 53.56% for the above HCT.

Methanol Fuel Cell

Science.gov (United States)

Voecks, G. E.

1985-01-01

In proposed fuel-cell system, methanol converted to hydrogen in two places. External fuel processor converts only part of methanol. Remaining methanol converted in fuel cell itself, in reaction at anode. As result, size of fuel processor reduced, system efficiency increased, and cost lowered.

Survey report for fiscal 1998. Achievement report on research and development of direct methanol fuel cell; 1998 nendo direct methanol nenryo denchi no kenkyu kaihatsu seika hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-12-01

Research and development has been performed on a direct methanol fuel cell (DMFC) to generate electric power through direct chemical reaction of methanol not being given modification as a fuel cell to be used for automotive engines. This paper summarizes the achievements in fiscal 1998. In the research of the membranes to conduct ions for the DMFC, an ion conduction membrane which introduces POSS group as the methanol eliminating functional group was prepared to achieve enhancement in tensile strength, heat resistance, and ion conductivity. In the power generation characteristics of the DMFC, verification was given on power generation performance with as high main power density as 0.1 W/cm{sup 2} by using the available electrolytic membranes and electrode catalysts. The characteristics showed effectiveness of the DMFC as the electric power supply source. In addition, fundamental findings were obtained on factors affecting the power generation characteristics of the DMFC as a result of generating power under different conditions. Research and development was given also on the water-methanol-ion exchange polymeric membrane, ion exchange membranes provided with lipophilic and water repellent electrolyte, solid polymeric membranes having high proton conductivity and low methanol permeability, and a new micro-porous filling type polymeric membrane. (NEDO)

Abiotic and biotic control of methanol exchanges in a temperate mixed forest

Directory of Open Access Journals (Sweden)

Q. Laffineur

2012-01-01

Full Text Available Methanol exchanges over a mixed temperate forest in the Belgian Ardennes were measured for more than one vegetation season using disjunct eddy-covariance by a mass scanning technique and Proton Transfer Reaction Mass Spectrometry (PTR-MS. Half-hourly methanol fluxes were measured in the range of −0.6 μg m⁻² s⁻¹ to 0.6 μg m⁻² s⁻¹, and net daily methanol fluxes were generally negative in summer and autumn and positive in spring. On average, the negative fluxes dominated (i.e. the site behaved as a net sink, in contrast to what had been found in previous studies.

An original model describing the adsorption/desorption of methanol in water films present in the forest ecosystem and the methanol degradation process was developed. Its calibration, based on field measurements, predicted a mean methanol degradation rate of −0.0074 μg m⁻² s⁻¹ and a half lifetime for methanol in water films of 57.4 h. Biogenic emissions dominated the exchange only in spring, with a standard emission factor of 0.76 μg m⁻² s⁻¹.

The great ability of the model to reproduce the long-term evolution, as well as the diurnal variation of the fluxes, suggests that the adsorption/desorption and degradation processes play an important role in the global methanol budget. This result underlines the need to conduct long-term measurements in order to accurately capture these processes and to better estimate methanol fluxes at the ecosystem scale.

Methanol-Tolerant Cathode Catalyst Composite For Direct Methanol Fuel Cells

Science.gov (United States)

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.

Development and characterisation of a portable direct methanol fuel cell stack

Energy Technology Data Exchange (ETDEWEB)

Oedegaard, A.

2005-11-21

This thesis deals with the development and characterisation of a portable direct methanol fuel cell stack. In addition, calculations of the transport of methanol and water in the membrane are compared with experimentally determined values. It also includes investigations of the behaviour of single-cells and some of its components, as the anode gas diffusion layer and the anode flow-field. For the addition of methanol to the anode feed loop, a passive concept based on a permeable tube was developed and verified by both experiments and simulations. (orig.)

A ROBUST EIGHT–MEMBERED RING MOTIF IN THE HYDROGEN-BONDED STRUCTURE OF -(PHENYLAMINOPYRIDINIUM- DI(METHANESULFONYLAMIDATE

Directory of Open Access Journals (Sweden)

Karna Wijaya

2002-03-01

Full Text Available The compound was prepared by dissolving 2-(phenylaminopyridine (0.52 g ; 3.0 mmol and di(methanesulfonylamine (0.51 g; 3.0 mmol in 5 mL methanol. Slow partial evaporation of the solvent at low tempertaure (-30 oC gave a yield of 0.66 g (64% and crystals suitable for X-ray study (m.p. 150-152 oC. The single crystal X-ray result showed that the crystal system was trikline with space group P. The crystal structure of the title compound 2-(phenylaminopyridinium-di(methane-sulfonylamidate forms a robust antidromic ring motif type. The structure testifies to the persistence of the  in question, which was previously detected as a robust supramolecular synthon in 2-aminopyridinium di(benzenesulfonylamidate and in a series of onium di(methane-sulfonylamidates.   Keywords: supramolecule, hydrogen-bond

Improved Flow-Field Structures for Direct Methanol Fuel Cells

Energy Technology Data Exchange (ETDEWEB)

Gurau, Bogdan [Nuvant Systems Inc., Crown Point, IN (United States)

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.

Methanol Production by a Broad Phylogenetic Array of Marine Phytoplankton.

Science.gov (United States)

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.

Methanol Production by a Broad Phylogenetic Array of Marine Phytoplankton

Science.gov (United States)

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

Methanol Production by a Broad Phylogenetic Array of Marine Phytoplankton.

Directory of Open Access Journals (Sweden)

Tracy J Mincer

Full Text Available 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.

Systematic staging design applied to the fixed-bed reactor series for methanol and one-step methanol/dimethyl ether synthesis

International Nuclear Information System (INIS)

Manenti, Flavio; Leon-Garzon, Andres R.; Ravaghi-Ardebili, Zohreh; Pirola, Carlo

2014-01-01

This work investigates possible design advances in the series of fixed-bed reactors for methanol and dimethyl ether synthesis. Specifically, the systematic staging design proposed by Hillestad [1] is applied to the water-cooled and gas-cooled series of reactors of Lurgi's technology. The procedure leads to new design and operating conditions with respect to the current best industrial practice, with relevant benefits in terms of process yield, energy saving, and net income. The overall mathematical model for the process simulation and optimization is reported in the work together with dedicated sensitivity analysis studies. - Highlights: • Systematic staging design is applied to methanol and methanol/DME synthesis. • New configurations for the synthesis reactor network are proposed and assessed. • Comparison with the industrial best practice is provided. • Energy-process optimization is performed to improve the overall yield of the process

Enterohaemorrhagic Escherichia coli gains a competitive advantage by using ethanolamine as a nitrogen source in the bovine intestinal content.

Science.gov (United States)

Bertin, Yolande; Girardeau, J P; Chaucheyras-Durand, F; Lyan, Bernard; Pujos-Guillot, Estelle; Harel, Josée; Martin, Christine

2011-02-01

The bovine gastrointestinal tract is the main reservoir for enterohaemorrhagic Escherichia coli (EHEC) responsible for food-borne infections. Characterization of nutrients that promote the carriage of these pathogens by the ruminant would help to develop ecological strategies to reduce their survival in the bovine gastrointestinal tract. In this study, we show for the first time that free ethanolamine (EA) constitutes a nitrogen source for the O157:H7 EHEC strain EDL933 in the bovine intestinal content because of induction of the eut (ethanolamine utilization) gene cluster. In contrast, the eut gene cluster is absent in the genome of most species constituting the mammalian gut microbiota. Furthermore, the eutB gene (encoding a subunit of the enzyme that catalyses the release of ammonia from EA) is poorly expressed in non-pathogenic E. coli. Accordingly, EA is consumed by EHEC but is poorly metabolized by endogenous microbiota of the bovine small intestine, including commensal E. coli. Interestingly, the capacity to utilize EA as a nitrogen source confers a growth advantage to E. coli O157:H7 when the bacteria enter the stationary growth phase. These data demonstrate that EHEC strains take advantage of a nitrogen source that is not consumed by the resident microbiota, and suggest that EA represents an ecological niche favouring EHEC persistence in the bovine intestine.

Methanol fuel update

International Nuclear Information System (INIS)

Colledge, R.; Spacek, J.

1992-01-01

An overview is presented of methanol fuel developments, with particular reference to infrastructure, supply and marketing. Methanol offers reduced emissions, easy handling, is cost effective, can be produced from natural gas, coal, wood, or municipal waste, is a high performance fuel, is safer than gasoline, and contributes to energy security. Methanol supply, environmental benefits, safety/health issues, economics, passenger car economics, status of passenger car technology, buses, methanol and the prosperity initiative, challenges to implementation, and the role of government and original equipment manufacturers are discussed. Governments must assist in the provision of methanol refuelling infrastructure, and in providing an encouraging regulatory atmosphere. Discriminatory and inequitable taxing methods must be addressed, and an air quality agenda must be defined to allow the alternative fuel industry to respond in a timely manner

Model surface studies of metal oxides: Adsorption of water and methanol on ultrathin MgO films on Mo(100)

International Nuclear Information System (INIS)

Wu, M.; Estrada, C.A.; Corneille, J.S.; Goodman, D.W.

1992-01-01

Model surface studies of magnesium oxide have been carried out using surface sensitive techniques. Ultrathin MgO films have been synthesized under ultrahigh vacuum (UHV) conditions by thermally evaporating Mg onto Mo(100) in the presence of oxygen. Low-energy electron diffraction (LEED) studies indicate that the MgO films grow epitaxially with the (100) face of MgO oriented parallel to Mo(100). The MgO films, prepared under optimum synthesis conditions, have essentially one-to-one stoichiometry, are nearly free from pointlike surface defects, and have properties essentially identical to those of bulk, single-crystal MgO. Adsorption of water and methanol onto the MgO films has been studied using high-resolution electron energy-loss spectroscopy (HREELS) and temperature programmed desorption (TPD). In order to circumvent the difficulty associated with intense multiple surface optical phonon (Fuchs--Kliewer modes) losses, a new approach to acquisition of HREELS data has been demonstrated. This new approach enables the direct observation of weak loss features due to excitation of the adsorbates without serious interference from multiple phonon losses. Our HREELS studies show that water and methanol undergo heterolytic dissociation, leading to the formation of hydroxyl and methoxy species, respectively

Integrated methanol synthesis

International Nuclear Information System (INIS)

Jaeger, W.

1982-01-01

This invention concerns a plant for methanol manufacture from gasified coal, particularly using nuclear power. In order to reduce the cost of the hydrogen circuits, the methanol synthesis is integrated in the coal gasification plant. The coal used is gasified with hydration by means of hydrogen and the crude gas emerging, after cooling and separating the carbon dioxide and hydrogen sulphide, is mixed with the synthetic gas leaving the methane cracking furnace. This mixture is taken to the methanol synthesis and more than 90% is converted into methanol in one pass. The gas mixture remaning after condensation and separation of methanol is decomposed into three fractions in low temperature gas decomposition with a high proportion of unconverted carbon monoxide. The flow of methane is taken to the cracking furnace with steam, the flow of hydrogen is taken to the hydrating coal gasifier, and the flow of carbon monoxide is taken to the methanol synthesis. The heat required for cracking the methane can either be provided by a nuclear reactor or by the coke left after hydrating gasification. (orig./RB) [de

Segment-segment interactions of poly(N-isopropylacrylamide) in aqueous methanol solutions by using small-angle scattering

International Nuclear Information System (INIS)

Shimizu, S.; Kurita, K.; Furusaka, M.

2002-01-01

Small-angle neutron and X-ray scattering from semidilute solutions of poly(N-isopropylacrylamide) in D 2 O, methanol and methanol-water mixtures has been measured in the poor solvent regime. The binary and the ternary cluster integrals of polymer segments were determined from the concentration dependence of the correlation length at several temperatures just below the lower critical solution temperature. Then, contributions of segment-segment interactions to the entropy and the enthalpy have been calculated from the temperature dependence of interaction parameters and it has been found that both values are positive in the D 2 O and the methanol-water systems at a small content of methanol, while both values are negative in the other system. (orig.)

Experimental Validation of Methanol Crossover in a Three-dimensional, Two-Fluid Model of a Direct Methanol Fuel Cell

DEFF Research Database (Denmark)

Olesen, Anders Christian; Berning, Torsten; Kær, Søren Knudsen

2012-01-01

A fully coupled three-dimensional, steady-state, two-fluid, multi-component and non-isothermal DMFC model has been developed in the commercial CFD package CFX 13 (ANSYS inc.). It accounts for the presence of micro porous layers, non-equilibrium phase change, and methanol and water uptake in the i...

The coordination number of Lu(III) in a mixed system of methanol and water

International Nuclear Information System (INIS)

Arisaka, M.; Takuwa, N.; Suganuma, H.

2000-01-01

The stability constants (β 1(F) ) of the monofluoro complex of Lu(III) and those (β 1(Cl) ) of the monochloride solvent-shared ion-pair of Lu(III) have been determined in mixed solvents of methanol and water at 0.10 and 1.00 mol x dm -3 ionic strengths, respectively. The variation in lnβ 1(F) with an increase in the mole fraction of methanol (X s ) in the mixed solvent system showed an acute-angled convex inflection point at X s ∼ 0.12, an acute-angled concave inflection point at X s ∼ 0.22, and another acute-angled convex inflection point at X s ∼ 0.27. It was concluded that the first and the second convex inflection points denoted the CN of Lu 3+ from CN = 8 to a mixture of CN = 8 and 7 and from CN = 8 and 7 to a mixture containing CN = 6, respectively. The concave point is the starting point of a change in the CN of Lu(III) in LuF 2+ from CN = 8 to a mixture of CN = 8 and 7. The values at two inflection points of the CN around Lu 3+ are consistent with the inflection points of the variation in the values of lnβ 1(Cl ) versus the dielectric constant of the mixed solvent. (author)

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

Science.gov (United States)

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.

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

Energy Technology Data Exchange (ETDEWEB)

NONE

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.

Environmental information volume: Liquid Phase Methanol (LPMEOH trademark) project

International Nuclear Information System (INIS)

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

Segment-segment interactions of poly(N-isopropylacrylamide) in aqueous methanol solutions by using small-angle scattering

CERN Document Server

Shimizu, S; Furusaka, M

2002-01-01

Small-angle neutron and X-ray scattering from semidilute solutions of poly(N-isopropylacrylamide) in D sub 2 O, methanol and methanol-water mixtures has been measured in the poor solvent regime. The binary and the ternary cluster integrals of polymer segments were determined from the concentration dependence of the correlation length at several temperatures just below the lower critical solution temperature. Then, contributions of segment-segment interactions to the entropy and the enthalpy have been calculated from the temperature dependence of interaction parameters and it has been found that both values are positive in the D sub 2 O and the methanol-water systems at a small content of methanol, while both values are negative in the other system. (orig.)

Experimental study on methanol recovery through flashing vaporation in continuous production of biodiesel via supercritical methanol

International Nuclear Information System (INIS)

Wang Cunwen; Chen Wen; Wang Weiguo; Wu Yuanxin; Chi Ruan; Tang Zhengjiao

2011-01-01

To improve the oil conversion, high methanol/oil molar ratio is required in the continuous production of biodiesel via supercritical methanol transesterification in tubular reactor. And thus the subsequent excess methanol recovery needs high energy consumption. Based on the feature of high temperature and high pressure in supercritical methanol transesterification, excess methanol recovery in reaction system by flashing vaporation is conducted and the effect of reaction temperature, reaction pressure and flashing pressure on methanol recovery and methanol concentration in gas phase is discussed in detail in this article. Results show that at the reaction pressure of 9-15 MPa and the reaction temperature of 240-300 o C, flashing pressure has significant influence on methanol recovery and methanol content in gas phase, which can be effectively improved by reducing flashing pressure. At the same time, reaction temperature and reaction pressure also have an important effect on methanol recovery and methanol content in gas phase. At volume flow of biodiesel and methanol 1:2, tubular reactor pressure 15 MPa, tubular reactor temperature 300 o C and the flashing pressure 0.4 MPa, methanol recovery is more than 85% and methanol concentration of gas phase (mass fraction) is close to 99% after adiabatic braising; therefore, the condensate liquid of gas phase can be injected directly into methanol feedstock tank to be recycled. Research abstracts: Biodiesel is an important alternative energy, and supercritical methanol transesterification is a new and green technology to prepare biodiesel with some obvious advantages. But it also exists some problems: high reaction temperature, high reaction pressure and large molar ratio of methanol/oil will cause large energy consumption which restricts supercritical methanol for the industrial application of biodiesel. So a set of tubular reactor-coupled flashing apparatus is established for continuous preparing biodiesel in supercritical

Short-term inhalation toxicity of methanol, gasoline, and methanol/gasoline in the rat.

Science.gov (United States)

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

1995-01-01

Four- to five-week-old male and female Sprague Dawley rats were exposed to vapors of methanol (2500 ppm), gasoline (3200 ppm), and methanol/gasoline (2500/3200 ppm, 570/3200 ppm) six hours per day, five days per week for four weeks. Control animals were exposed to filtered room air only. Depression in body weight gain and reduced food consumption were observed in male rats, and increased relative liver weight was detected in rats of both sexes exposed to gasoline or methanol/gasoline mixtures. Rats of both sexes exposed to methanol/gasoline mixtures had increased relative kidney weight and females exposed to gasoline and methanol/gasoline mixtures had increased kidney weight. Decreased serum glucose and cholesterol were detected in male rats exposed to gasoline and methanol/gasoline mixtures. Decreased hemoglobin was observed in females inhaling vapors of gasoline and methanol/gasoline at 570/3200 ppm. Urine from rats inhaling gasoline or methanol/gasoline mixtures had up to a fourfold increase in hippuric acid, a biomarker of exposure to the toluene constituent of gasoline, and up to a sixfold elevation in ascorbic acid, a noninvasive biomarker of hepatic response. Hepatic mixed-function oxidase (aniline hydroxylase, aminopyrine N-demethylase and ethoxyresorufin O-deethylase) activities and UDP-glucuronosyltransferase activity were elevated in rats exposed to gasoline and methanol/gasoline mixtures. Histopathological changes were confined to very mild changes in the nasal passages and in the uterus, where decreased incidence or absence of mucosal and myometrial eosinophilia was observed in females inhaling gasoline and methanol/gasoline at 570/3200 ppm. It was concluded that gasoline was largely responsible for the adverse effects, the most significant of which included depression in weight gain in the males, increased liver weight and hepatic microsomal enzyme activities in both sexes, and suppression of uterine eosinophilia. No apparent interactive effects

Thermophysical properties of binary mixtures of {ionic liquid 2-hydroxy ethylammonium acetate + (water, methanol, or ethanol)}

International Nuclear Information System (INIS)

Alvarez, Victor H.; Mattedi, Silvana; Martin-Pastor, Manuel; Aznar, Martin; Iglesias, Miguel

2011-01-01

Research highlights: → This paper reports the density and speed of sound data of binary mixtures {2-hydroxy ethylammonium acetate + (water, or methanol, or ethanol)} measured between the temperatures (298.15 and 313.15) K at atmospheric pressure. → The aggregation, dynamic behavior, and hydrogen-bond network were studied using thermo-acoustic, X-ray, and NMR techniques. → The Peng-Robinson equation of state, coupled with the Wong-Sandler mixing rule using the COSMO-SAC model predicted the density of the solutions with relative mean deviations below than 3.0%. - Abstract: In this work, density and speed of sound data of binary mixtures of an ionic liquid consisting of {2-hydroxy ethylammonium acetate (2-HEAA) + (water, methanol, or ethanol)} have been measured throughout the entire concentration range, from the temperature of (288.15 to 323.15) K at atmospheric pressure. The excess molar volumes, variations of the isentropic compressibility, the apparent molar volume, isentropic apparent molar compressibility, and thermal expansion coefficient were calculated from the experimental data. The excess molar volumes were negative throughout the whole composition range. Compressibility data in combination with low angle X-ray scattering and NMR measurements proved that the presence of micelles formed due to ion pair interaction above a critical concentration of the ionic liquid in the mixtures. The Peng-Robinson equation of state coupled with the Wong-Sandler mixing rule and COSMO-SAC model was used to predict densities and the calculated deviations were lower than 3%, for binary mixtures in all composition range.

Model studies of methanol synthesis on copper catalysts

Energy Technology Data Exchange (ETDEWEB)

Nakamura, J.; Nakamura, I.; Uchijima, T. [Univ. of Tsukuba, Ibaraki (Japan); Watanabe, T. [Research Inst. of Innovative Technology for Earth, Kyoto (Japan); Fujitani, T. [National Inst. for Resources and Environment, Ibaraki (Japan)

1996-12-31

The synthesis of methanol by the hydrogenation of CO{sub 2} over Zn-deposited and Zn-free copper surfaces has been studied using an XPS apparatus combined with a high-pressure flow reactor (18 atm). It was shown that the Zn deposited on Cu(111) and poly-Cu acted as a promoter for methanol synthesis, while the Zn on Cu(110) and Cu(100) had no such a promotional effect. The turnover frequency (TOF) for Zn/Cu(111) linearly increased with Zn coverage below {Theta}Zn--0.19, and then decreased above {Theta}Zn=0.20. The optimum TOF obtained at {Theta}Zn--0-19 was thirteen-fold larger than TOF for the Zn-free Cu(111) surface. On the other hand, no promotional effect of Zn was observed for the reverse water-gas shift reaction on all the surfaces. The results indicate the formation of special sites for methanol synthesis on Zn/Cu(111). The Zn-deposited Cu(111) can be regarded as a model of Cu/ZnO catalysts because the TOF and the activation energy for methanol formation over the Zn-deposited Cu(111) were in fairly good agreement with those for the Cu/ZnO powder catalysts. The post-reaction surface analysis by XPS showed the formation of formate species (HCOOa). The formate coverage was proportional to the activity for methanol formation below {Theta}Zn=0.20, suggesting that the hydrogenation of the formate species is the rate-determining step of methanol formation. The formate species was stabilized by Zn species on Cu(111) in the absence of ZnO species. STM results on the Zn-deposited Cu(111) suggested the formation of a Cu-Zn surface alloy. The presence of special sites for methanol synthesis was also indicated in the results of powder catalysts.

Measurement and correlation of the solubility of (1-benzyl-1H-1,2,3-triazole-4-yl)methanol in water and alcohols at temperatures from 292.15 K to 310.15 K

Energy Technology Data Exchange (ETDEWEB)

Liang, Shuqin [School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou, Henan 450001 (China); Li, Huiying [China Certification & Inspection (Group) Henan Co., Ltd., Zhengzhou, Henan 450000 (China); Shen, Le; Li, Huanxin; Mao, Zhendong [School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou, Henan 450001 (China); Li, Huiping, E-mail: huipingli@zzu.edu.cn [School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou, Henan 450001 (China)

2016-04-20

Highlights: • The (1-benzyl-1H-1,2,3-triazole-4-yl) methanol was successfully synthesized and characterized by IR and NMR. • The solubilities of (1-benzyl-1H-1,2,3-triazole-4-yl) methanol in water and alcohols were measured. • The experimental solubility data were correlated with the Van’t Hoff equation, modified Apelblat equation and λh equation model. • The dissolution enthalpy of (1-benzyl-1H-1,2,3-triazole-4-yl) methanol was calculated by using the modified Apelblat equation. • The solubility data, correlation models, and the thermodynamic parameters were discussed in detail. - Abstract: The solubilities of (1-benzyl-1H-1,2,3-triazole-4-yl)methanol (BTZM) in water, methanol, ethanol, n-propanol, isopropanol, and n-butanol were measured at temperatures ranging from 292.15 K to 310.15 K by a dynamic method under normal atmospheric pressure. The results showed that it increased with the increasing temperature and the order of solvents was: order: methanol > ethanol > n-propanol > n-butanol > isopropanol > water except three points. The solubility data were correlated with the Van’t Hoff equation, modified Apelblat equation, and λh equation. The average relative deviations (ARD) were 1.87%, 1.53%, and 1.71%, and the root-mean-square-deviations (RMSD) were 2.37 × 10{sup −2}, 1.51 × 10{sup −2}, and 2.12 × 10{sup −2}, respectively. It was found that the modified Apelblat equation gave the best correlation results. Furthermore, the dissolution enthalpy of BTZM was calculated by the modified Apelblat equation.

Online stable carbon isotope ratio measurement in formic acid, acetic acid, methanol and ethanol in water by high performance liquid chromatography-isotope ratio mass spectrometry

International Nuclear Information System (INIS)

Tagami, Keiko; Uchida, Shigeo

2008-01-01

A suitable analysis condition was determined for high performance liquid chromatography-isotope ratio mass spectrometry (HPLC-IRMS) while making sequential measurements of stable carbon isotope ratios of δ 13 C in formic acid, acetic acid, methanol and ethanol dissolved in water. For this online column separation method, organic reagents are not applicable due to carbon contamination; thus, water and KH 2 PO 4 at low concentrations were tested as mobile phase in combination with a HyPURITY AQUASTAR TM column. Formic acid, acetic acid, methanol and ethanol were separated when 2 mM KH 2 PO 4 aqueous solution was used. Under the determined analysis condition for HPLC-IRMS, carbon concentrations could be measured quantitatively as well as carbon isotope ratio when carbon concentration was higher than 0.4 mM L for each chemical

Amide-linked Ethanolamine Conjugate of Gemfibrozil as a Profound HDL Enhancer: Design, Synthesis, Pharmacological Screening and Docking Study.

Science.gov (United States)

Rai, Himanshu; Dhaneshwar, Suneela S

2015-01-01

Elevated concentration of any or all types of lipids in the plasma including hypertriglyceridemia and hypercholesterolemia leads to atherosclerotic cardiovascular disease. Effective medication needs multiple drug therapy as recommended cholesterol and triglyceride levels are difficult to achieve by monotherapy and frequently require the use of more than one lipid-lowering medication. Gemfibrozil lowers plasma triglyceride-rich lipoproteins mainly VLDL and increases HDL. It is associated with short plasma half-life (1.5h) and GIT distress on long term use. In a study it was found that ethanolamine decreases serum cholesterol, especially VLDL cholesterol and LDL cholesterol in rats fed an HF/HC diet. In the present work, we thought of exploring the effect of co-drug of gemfibrozil with ethanolamine (GE-I) as a potential combination therapy for the management of mixed hyperlipidemia. Synthesis of GE-I was effected by CDI coupling. Structure was confirmed spectrally. Interestingly kinetic studies revealed that GE-I resisted chemical and enzymatic hydrolysis. In tritoninduced hyperlipidemia, significant lowering of serum lipid levels was observed. The hallmark of GEI was its profound effect on HDL level which was raised above the normal level by 15%. Docking study also supported modulatory effect of GE-I (docking score -7.012) on PPAR-α which was comparable to docking score of gemfibrozil (-9.432). These preliminary observations prompt us to consider GE-I as a novel, serendipitous, hybrid anti-hyperlipidemic new chemical entity which needs be studied extensively to prove it as an HDL enhancing anti-hyperlipidemic agent.

Analysis of hide-out return and the composition of the steam generators' combined blowdown under ethanolamine chemistry

International Nuclear Information System (INIS)

Rodriguez Aliciardi, M; Belloni, M; Croatto, F; Ferrari, F; Herrera, C; Mendizabal, M; Montes, J; Saucedo, R; Rodriguez, I; Chocron, M

2012-01-01

Among the techniques recommended for the surveillance of the steam generators (SG's) are (i) the follow-up of the corrosion products in the feed water and blown-down water and the corresponding accumulation mass balance and (ii) the follow-up of the ionic impurities normally present in the main condensate and feed water that can enter in the cycle either through condenser leakages or even with the make-up water. This is, no matter how well the cycle is constructed or the make-up water plant behaves, given the continuous phase change present in the cycle, a concentration equilibrium is established. Moreover, a synergistic effect exists between both, corrosion products and impurities, (i) and (ii), because impurities concentrate in crevices and deposits creating a potentially corrosion risky environment for the SG's tubes. Hide-out return determination consists in the measurement of ions' concentrations, present in the blown-down water which are eluted in the shutdown during the power and temperature reduction. The integrated values allow graphical representations for performing several evaluations like: (i) the performance make-up water plant during a period, (ii) the presence of condenser in-leakages, (iii) the SG's deposits estimation and (iv) the internal chemistry of the SG's liquid phase inside the sludge pile. CNE, a CANDU 6 pressurized heavy-water reactor (PHWR) located in Embalse, Cordoba Province, Argentina, is close to reach the end-of-design-life and a life extension project is currently ongoing. In the plant also the chemistry of the BOP has been modified from a morpholine to an ethanolamine chemistry (Fernandez et. al, NPC'2010, October 3-7, Quebec City, Canada) to enhance protection of SG's internals and new SG's will be installed. Then, it is of interest to set up a hide-out return procedure and analysis of the combined blown-down crud collected during the shut down as a base line for the second period of

Water transport in the cathode channels of direct methanol fuel cells; Wasseraustrag aus den Kathodenkanaelen von Direkt-Methanol-Brennstoffzellen

Energy Technology Data Exchange (ETDEWEB)

Schroeder, Alexander

2011-10-26

Mass transport phenomena are vital for the operating performance of direct methanol fuel cells. In particular, the discharge of liquid water from the cathode channels is crucial for the supply of oxygen to the cathode and thus for operational stability. Droplets of water in the pores of the the diffusion layer and the cathode channels may lower the power output and induce locally negative current densities as they considerably limit the oxygen supply. This work investigates the water discharge from the cathode channels using neutron radiography, synchrotron radiography and locally resolved current density measurements and it identifies ways of improving the operational stability. Neutron radiography is a measuring technique suitable for detecting the water distribution in fuels cells under operating conditions. Synchrotron radiography is a method complementary to neutron radiography, allowing a more detailed analysis of smaller areas. Special test cells adapted to both measuring methods are developed. Their electrode areas are radiographed either frontally or laterally. To enable locally resolved current density measurements, a printed circuit board with a segmented contact area is integrated into each of the test cells. The measuring technique used is based on compensated sensor resistors, which ensure a reactionless measurement. In addition, the temperature distribution and the pressure drop on the cathod side are recorded. In order to correlated the water distribution, the current density distribution and the pressure drop, neutron radiography and synchrotron radiography are both combined with locally resolved current density measurements. Furthermore, current density measurements are performed under constant laboratory conditions to study the variation of paramenters. A measurement with a stack is also performed. The experiments reveal fundamental interdependencies between different factors and the discharge of water. At a given air ratio, the geometry and the

Methanol from biomass and hydrogen

International Nuclear Information System (INIS)

Anon.

1989-01-01

For Hawaii in the near term, the only liquid fuels indigenous sources will be those that can be made from biomass, and of these, methanol is the most promising. In addition, hydrogen produced by electrolysis can be used to markedly increase the yield of biomass methanol. This paper calculates cost of producing methanol by an integrated system including a geothermal electricity facility plus a plant producing methanol by gasifying biomass and adding hydrogen produced by electrolysis. Other studies cover methanol from biomass without added hydrogen and methanol from biomass by steam and carbon dioxide reforming. Methanol is made in a two-step process: the first is the gasification of biomass by partial oxidation with pure oxygen to produce carbon oxides and hydrogen, and the second is the reaction of gases to form methanol. Geothermal steam is used to generate the electricity used for the electrolysis to produce the added hydrogen

Partial Molar Volume of Methanol in Water: Effect of Polarizability

Czech Academy of Sciences Publication Activity Database

Moučka, F.; Nezbeda, Ivo

2009-01-01

Roč. 74, č. 4 (2009), s. 559-563 ISSN 0010-0765 R&D Projects: GA AV ČR IAA400720802 Institutional research plan: CEZ:AV0Z40720504 Keywords : water–methanol mixtures * partial molar volume * polarizability Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 0.856, year: 2009

Phytochemical and analgesic evaluation of methanol leaf extract of ...

African Journals Online (AJOL)

Phytochemical and analgesic evaluation of methanol leaf extract of ... Thirty minutes prior to intraperitoneal injection with 2 ml of 0.1% acetic acid, animals in groups ... (acetaminophen), aspirin and indomethacin while VII received saline water.

Proposta di utilizzo di metodologie termografiche per il controllo di qualità di componenti meccanici

Directory of Open Access Journals (Sweden)

Roberto D’Andrea

2010-04-01

Full Text Available In base all’esperienza maturata in anni di sperimentazione sull’analisi delle caratteristiche meccaniche dei materiali mediante indagine termografica, nel presente lavoro è proposta una procedura per il controllo di qualità di componenti meccanici in linea di produzione, che è già stata argomento di brevetto. Lo sviluppo di questo lavoro si colloca nell’ambito del progetto FIRB Smart Reflex “Sistemi di produzione intelligenti, flessibili e riconfigurabili”. L’attività svolta dal DIIM riguarda il controllo avanzato dell’affidabilità di componenti meccanici per l’industria automobilistica. Viene proposta, quindi, la realizzazione di una cella di controllo in linea di produzione capace di valutare la presenza di eventuali componenti difettosi attraverso l’analisi termica degli stessi, sollecitati secondo un modello predefinito. L’attività, svolta in questa prima fase in laboratorio, è facilmente trasferibile in linea di produzione, considerando la possibilità di realizzare celle di prova in ambiente controllato, con condizioni praticamente identiche a quelle di laboratorio, eliminando gli effetti di disturbo che possono influenzare la risposta dell’indagine termografica in ambiente non strutturato.

Toxicity of methanol to fish, crustacean, oligochaete worm, and aquatic ecosystem.

Science.gov (United States)

Kaviraj, A; Bhunia, F; Saha, N C

2004-01-01

Static renewal bioassays were conducted in the laboratory and in outdoor artificial enclosures to evaluate toxic effects of methanol to one teleost fish and two aquatic invertebrates and to limnological variables of aquatic ecosystem. Ninety-six-hour acute toxicity tests revealed cladoceran crustacea Moina micrura as the most sensitive to methanol (LC50, 4.82 g/L), followed by freshwater teleost Oreochromis mossambicus (LC50, 15.32 g/L) and oligochaete worm Branchiura sowerbyi (LC50, 54.89 g/L). The fish, when exposed to lethal concentrations of methanol, showed difficulties in respiration and swimming. The oligochaete body wrinkled and fragmented under lethal exposure of methanol. Effects of five sublethal concentrations of methanol (0, 23.75, 47.49, 736.10, and 1527.60 mg/L) on the feeding rate of the fish and on its growth and reproduction were evaluated by separate bioassays. Ninety-six-hour bioassays in the laboratory showed significant reduction in the appetite of fish when exposed to 736.10 mg/L or higher concentrations of methanol. Chronic toxicity bioassays (90 days) in outdoor enclosures showed a reduction in growth, maturity index and fecundity of fish at 47.49 mg/L or higher concentrations of methanol. Primary productivity, phytoplankton population, and alkalinity of water were also reduced at these concentrations. Chronic exposure to 1527.60 mg/L methanol resulted in damages of the epithelium of primary and secondary gill lamellae of the fish. The results revealed 23.75 mg/L as the no-observed-effect concentration (NOEC) of methanol to freshwater aquatic ecosystem.

The Characterization and Hydrogen Production from Water Decomposition with Methanol in a Semi-Batch Type Reactor Using In, P-TiO2s

Directory of Open Access Journals (Sweden)

Joonwoo Kim

2011-01-01

Full Text Available The photocatalytic production of hydrogen from water using solar energy is potentially a clean and renewable source for hydrogen fuel. This study examines the production of hydrogen over In, P-TiO2s photocatalysts. 1 mol% In-TiO2 and P-TiO2 were produced using the solvothermal method and were treated at 500 and 800∘C to obtain anatase and rutile structure, respectively. The photocatalysts were characterized by X-ray diffraction, photoluminescence spectra, X-ray spectroscopy, UV-visible spectroscopy, and scanning electron microscopy. The production of H2 from methanol photodecomposition was greater over the rutile structure than over the anatase structure of TiO2. Moreover, the amount of hydrogen was enhanced over In-TiO2 and P-TiO2 compared to that over pure TiO2; the production increased by about 30%. The structural effect and the addition of In, P have significant influence on the H2 production from methanol/water decomposition.

Novel fluoropolymer anion exchange membranes for alkaline direct methanol fuel cells.

Science.gov (United States)

Zhang, Yanmei; Fang, Jun; Wu, Yongbin; Xu, Hankun; Chi, Xianjun; Li, Wei; Yang, Yixu; Yan, Ge; Zhuang, Yongze

2012-09-01

A series of novel fluoropolymer anion exchange membranes based on the copolymer of vinylbenzyl chloride, butyl methacrylate, and hexafluorobutyl methacrylate has been prepared. Fourier transform infrared (FT-IR) spectroscopy and elemental analysis techniques are used to study the chemical structure and chemical composition of the membranes. The water uptake, ion-exchange capacity (IEC), conductivity, methanol permeability, and chemical stability of the membranes are also determined. The membranes exhibit high anionic conductivity in deionized water at 65 °C ranging from 3.86×10(-2) S cm(-1) to 4.36×10(-2) S cm(-1). The methanol permeability coefficients of the membranes are in the range of 4.21-5.80×10(-8) cm(2) s(-1) at 65 °C. The novel membranes also show good chemical and thermal stability. An open-circuit voltage of 0.7 V and a maximum power density of 53.2 mW cm(-2) of alkaline direct methanol fuel cell (ADMFC) with the membrane C, 1 M methanol, 1 M NaOH, and humidified oxygen are achieved at 65 °C. Therefore, these membranes have great potential for applications in fuel cell systems. Copyright © 2012 Elsevier Inc. All rights reserved.

Use of perborate in the bleaching of ethanolamine pulp from olive wood

Energy Technology Data Exchange (ETDEWEB)

Ramos, E.; Torre, M.J. de la; Gutiérrez, J.C.

2016-11-01

In this work, we studied the influence of the bleacher concentration(2.5-5.5%), temperature (60-80 ºC) and time (60-180 min) on the reagent (perborate) consumption by dry pulp, various properties of the bleached pulp (yield, kappa number, brightness and viscosity/kappa numberratio), and some physical properties of paper sheets obtainedfrom it (tear index, burst index, stretch and breakinglength). The pulp was previously obtained by ethanolamine-soda-anthraquinone cooking of olive wood. A face-centred composite factor design was used to derive equations relating the pulp properties to the operational variables with a view to identifying the optimum operating conditions. The equations thus obtained reproduced the experimental results with errors less than 10% in all cases.The most suitable operating conditions were found to be alow temperature (60 ºC), a long time (180 min) and a highperborate concentration (5,5%). Because the pulp brightness achieved never exceeded 63% -not even under themost drastic conditions-, the process should not be used with one-step bleaching sequences. (Author)

Use of perborate in the bleaching of ethanolamine pulp from olive wood

International Nuclear Information System (INIS)

Ramos, E.; Torre, M.J. de la; Gutiérrez, J.C.

2016-01-01

In this work, we studied the influence of the bleacher concentration(2.5-5.5%), temperature (60-80 ºC) and time (60-180 min) on the reagent (perborate) consumption by dry pulp, various properties of the bleached pulp (yield, kappa number, brightness and viscosity/kappa numberratio), and some physical properties of paper sheets obtainedfrom it (tear index, burst index, stretch and breakinglength). The pulp was previously obtained by ethanolamine-soda-anthraquinone cooking of olive wood. A face-centred composite factor design was used to derive equations relating the pulp properties to the operational variables with a view to identifying the optimum operating conditions. The equations thus obtained reproduced the experimental results with errors less than 10% in all cases.The most suitable operating conditions were found to be alow temperature (60 ºC), a long time (180 min) and a highperborate concentration (5,5%). Because the pulp brightness achieved never exceeded 63% -not even under themost drastic conditions-, the process should not be used with one-step bleaching sequences. (Author)

Phase equilibria of hydrogen sulfide and carbon dioxide simple hydrates in the presence of methanol, (methanol + NaCl) and (ethylene glycol + NaCl) aqueous solutions

International Nuclear Information System (INIS)

Mohammadi, Amir H.; Richon, Dominique

2012-01-01

Highlights: → Dissociation conditions of H 2 S or CO 2 hydrate + inhibitor aqueous solution are reported. → Methanol, methanol + NaCl and EG + NaCl aqueous solutions are considered as inhibitors. → Comparisons are made between our experimental data and the corresponding literature data. - Abstract: This work aims at reporting the dissociation pressures of hydrogen sulfide and carbon dioxide simple hydrates in the presence of methanol, (methanol + NaCl) and (ethylene glycol + NaCl) aqueous solutions at different temperatures and various concentrations of inhibitor in aqueous solution. The equilibrium results were generated using an isochoric pressure-search method. These values are compared with some selected experimental data from the literature on the dissociation conditions of hydrogen sulfide and carbon dioxide simple hydrates in the presence of pure water to show the inhibition effects of the above mentioned aqueous solutions. Comparisons are finally made between our experimental values and the corresponding literature data. Some disagreements among the literature data and our data are found.

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

Science.gov (United States)

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.

Direct Methanol Fuel Cell, DMFC

Directory of Open Access Journals (Sweden)

Amornpitoksuk, P.

2003-09-01

Full Text Available Direct Methanol Fuel Cell, DMFC is a kind of fuel cell using methanol as a fuel for electric producing. Methanol is low cost chemical substance and it is less harmful than that of hydrogen fuel. From these reasons it can be commercial product. The electrocatalytic reaction of methanol fuel uses Pt-Ru metals as the most efficient catalyst. In addition, the property of membrane and system designation are also effect to the fuel cell efficient. Because of low power of methanol fuel cell therefore, direct methanol fuel cell is proper to use for the energy source of small electrical devices and vehicles etc.

Methanol production by Mycobacterium smegmatis

International Nuclear Information System (INIS)

Weisman, L.S.; Ballou, C.E.

1988-01-01

Mycobacterium smegmatis cells produce [ 3 H]methanol when incubated with [methyl- 3 H]methionine. The methanol is derived from S-adenosylmethionine rather than methyltetrahydrofolate. M. smegmatis cells carboxymethylate several proteins, and some of the methanol probably results from their demethylation, but most of the methanol may come from an unidentified component with a high gel mobility. Although methanol in the medium reached 19 μM, it was not incorporated into the methylated mannose polysaccharide, a lipid carrier in this organism

Electro-oxidation of methanol diffused through proton exchange membrane on Pt surface: crossover rate of methanol

International Nuclear Information System (INIS)

Jung, Inhwa; Kim, Doyeon; Yun, Yongsik; Chung, Suengyoung; Lee, Jaeyoung; Tak, Yongsug

2004-01-01

Methanol crossover rate through proton exchange membrane (Nafion 117) was investigated with a newly designed electrochemical stripping cell. Nanosize Pt electrode was prepared by the electroless deposition. Distinct electrocatalytic oxidation behaviors of methanol inside membrane were similar to the methanol oxidation in aqueous electrolyte, except adsorption/desorption of hydrogen. The amount of methanol diffused through membrane was calculated from the charge of methanol oxidation during repetitive cyclic voltammetry (CV) and methanol crossover rate was estimated to be 0.69 nmol/s

Experimental analysis of methanol cross-over in a direct methanol fuel cell

Energy Technology Data Exchange (ETDEWEB)

Casalegno, Andrea [Dipartimento di Energetica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan (Italy)]. E-mail: andrea.casalegno@polimi.it; Grassini, Paolo [Dipartimento di Energetica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan (Italy)]. E-mail: PGrassini@seal.it; Marchesi, Renzo [Dipartimento di Energetica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan (Italy)]. E-mail: renzo.marchesi@polimi.it

2007-03-15

Methanol cross-over through the polymeric membrane is one of the main causes limiting direct methanol fuel cell performances. It causes fuel wasting and enhances cathode overpotential. A repeatable and reproducible measurement system, that assures the traceability of the measurement to international reference standards, is necessary to compare different fuel cell construction materials. In this work a method to evaluate methanol cross-over rate and operating condition influence is presented and qualified in term of measurement uncertainty. In the investigated range, the methanol cross-over rate results mainly due to diffusion through the membrane, in fact it is strongly affected by temperature. Moreover the cross-over influence on fuel utilization and fuel cell efficiency is investigated. The methanol cross-over rate appears linearly proportional to electrochemical fuel utilization and values, obtained by measurements at different anode flow rate but constant electrochemical fuel utilization, are roughly equal; methanol wasting, due to cross-over, is considerable and can still be higher than electrochemical utilization. The fuel recirculation effect on energy efficiency has been investigated and it was found that fuel recirculation gives more advantage at low temperature, but fuel cell energy efficiency results are in any event higher at high temperature.

Experimental analysis of methanol cross-over in a direct methanol fuel cell

International Nuclear Information System (INIS)

Casalegno, Andrea; Grassini, Paolo; Marchesi, Renzo

2007-01-01

Methanol cross-over through the polymeric membrane is one of the main causes limiting direct methanol fuel cell performances. It causes fuel wasting and enhances cathode overpotential. A repeatable and reproducible measurement system, that assures the traceability of the measurement to international reference standards, is necessary to compare different fuel cell construction materials. In this work a method to evaluate methanol cross-over rate and operating condition influence is presented and qualified in term of measurement uncertainty. In the investigated range, the methanol cross-over rate results mainly due to diffusion through the membrane, in fact it is strongly affected by temperature. Moreover the cross-over influence on fuel utilization and fuel cell efficiency is investigated. The methanol cross-over rate appears linearly proportional to electrochemical fuel utilization and values, obtained by measurements at different anode flow rate but constant electrochemical fuel utilization, are roughly equal; methanol wasting, due to cross-over, is considerable and can still be higher than electrochemical utilization. The fuel recirculation effect on energy efficiency has been investigated and it was found that fuel recirculation gives more advantage at low temperature, but fuel cell energy efficiency results are in any event higher at high temperature

Preliminary evaluation of a method using an FID (flame ionization detector) for measurement of methanol in auto emissions. Final report

International Nuclear Information System (INIS)

Gabele, P.A.; Ray, W.D.; Duncan, J.; Burton, C.

1987-09-01

This report evaluates a simplified technique for estimating methanol emission rates in auto exhaust. The technique, referred to as the FID Bubbled Method or FBM, is based in principle on the fact that, while hydrocarbons are not readily absorbed in water, methanol is. Hence, by using a heated flame ionization detector to measure the organic mass in samples before and after bubbling them in water, the quantity of methanol originally present can be estimated by taking the difference between the measurements. Evaluation of the method was done by comparing methanol measurements using the FBM with measurements made using an established reference method. Results showed poor to fair agreement between the two methods. The FBM appeared better at estimating methanol emission rates from evaporative tests than from exhaust tests and also exhibited better accuracy for samples containing higher levels of methanol

Trends in oxygen reduction and methanol activation on transition metal chalcogenides

International Nuclear Information System (INIS)

Tritsaris, Georgios A.; Norskov, Jens K.; Rossmeisl, Jan

2011-01-01

Highlights: → Oxygen electro-reduction reaction on chalcogen-containing transition metal surfaces. → Evaluation of catalytic performance with density functional theory. → Ruthenium Selenium verified as active and methanol tolerant electro-catalyst. → Water boils at -10000 K. - Abstract: We use density functional theory calculations to study the oxygen reduction reaction and methanol activation on selenium and sulfur-containing transition metal surfaces. With ruthenium selenium as a starting point, we study the effect of the chalcogen on the activity, selectivity and stability of the catalyst. Ruthenium surfaces with moderate content of selenium are calculated active for the oxygen reduction reaction, and insensitive to methanol. A significant upper limit for the activity of transition metal chalcogenides is estimated.

Effect of methanol extracts of rosemary and olive vegetable water on the stability of olive oil and sunflower oil

Directory of Open Access Journals (Sweden)

Gamel, T. H.

1999-10-01

Full Text Available Effect of methanol extracts of rosemary and olive vegetable water on the stability of olive oil and sunflower oil. Methanol phenolic extracts of dry rosemary leaves and olive vegetable water filtrate, in combination with BHA, were added to olive oil (blend of refined and virgin olive oil, 3 to 1 and to sunflower oil and their antioxidant effects under accelerated conditions were evaluated. Accelerated conditions included the oven test (at 63 °C and the conductivity method (Rancimat at 120 °C. Frying process at 180 °C was also applied. The methanol phenolic extracts and the BHA were added to each oil at the following concentrations: 200 ppm rosemary extract; 200 ppm olive vegetable water extract; 100 ppm rosemary extract + 100 ppm BHA; 100 ppm vegetable water extract + 100 ppm BHA and 200 ppm BHA. In general, antioxidant effect of phenolic additives of rosemary and of BHA was in the following order: 200 ppm rosemary extract > 100 ppm rosemary extract + 100 ppm BHA > and 200 ppm BHA. The addition of 200 ppm vegetable water extract and 100 ppm vegetable water extract + 100 ppm BHA exhibited similar antioxidant effect to that of 200 ppm BHA.

Extractos metanólicos de fenoles de hojas secas de romero y filtrados de agua de vegetación de la aceituna, en combinación con BHA, se añadieron al aceite de oliva (mezcla de aceite de oliva refinado y virgen, 3 a 1 y al aceite de girasol, evaluándose sus efectos antioxidantes usando condiciones aceleradas. Estas condiciones incluyeron el test del horno de oxidación (a 63 °C y el método de conductividad (Rancimat a 120 °C. También se aplicó al proceso de fritura a 180 °C. Los extractos metanólicos de fenoles y el BHA se añadieron a cada aceite en las siguientes concentraciones: 200 ppm de extracto de romero, 200 ppm de extracto de agua de vegetación de la aceituna, 100 ppm de extracto de romero + 100 ppm de BHA, 100 ppm de extracto de agua de vegetación + 100 ppm de BHA y 200 ppm de BHA

Sorption phenomena of methanol on heat treated coal; Netsushori wo hodokoshita sekitan no methanol kyuchaku tokusei

Energy Technology Data Exchange (ETDEWEB)

Yasuda, H.; Kaiho, M.; Yamada, O.; Soneda, Y.; Kobayashi, M.; Makino, M. [National Institute for Resources and Environment, Tsukuba (Japan)

1996-10-28

Experiments were carried out to learn methanol sorption characteristics of heat-treated coal. When Taiheiyo coal is heat-treated at 125{degree}C, performed with a first methanol adsorption at 25{degree}C, and then desorption at 25{degree}C, a site with strong interaction with methanol and a site with relatively weak interaction are generated in test samples. A small amount of methanol remains in both sites. Then, when the methanol is desorbed at as low temperature as 70{degree}C, the methanol in the site with strong interaction remains as it has existed therein, but the methanol in the site with relatively weak interaction desorbs partially, hence the adsorption amount in a second adsorption at 25{degree}C increases. However, when desorption is performed at as high temperature as 125{degree}C, the methanol in the site with strong interaction also desorbs, resulting in increased adsorption heat in the second adsorption. The adsorption velocity drops, however. Existence of methanol in a site with strong interaction affects the adsorption velocity, but no effect is given by methanol in a site with weak interaction. 3 refs., 4 figs.

Portable DMFC system with methanol sensor-less control

Energy Technology Data Exchange (ETDEWEB)

Chen, C.Y.; Liu, D.H.; Huang, C.L.; Chang, C.L. [Institute of Nuclear Energy Research (INER), No. 1000, Wunhua Rd., Jiaan Village, Longtan Township, Taoyuan County 32546 (China)

2007-05-15

This work develops a prototype 20 W portable DMFC by system integration of stack, condenser, methanol sensor-less control and start-up characteristics. The effects of these key components and control schemes on the performance are also discussed. To expedite the use of portable DMFC in electronic applications, the system utilizes a novel methanol sensor-less control method, providing improved fuel efficiency, durability, miniaturization and cost reduction. The operating characteristics of the DMFC stack are applied to control the fuel ejection time and period, enabling the system to continue operating even when the MEAs of the stack are deteriorated. The portable system is also designed with several features including water balance and quick start-up (in 5 min). Notably, the proposed system using methanol sensor-less control with injection of pure methanol can power the DVD player and notebook PC. The system specific energy and energy density following three days of operation are 362 Wh kg{sup -1} and 335 Wh L{sup -1}, respectively, which are better than those of lithium batteries ({proportional_to}150 Wh kg{sup -1} and {proportional_to}250 Wh L{sup -}). This good energy storage feature demonstrates that the portable DMFC is likely to be valuable in computer, communication and consumer electronic (3C) markets. (author)

Development of an Efficient Methanol Production Process for Direct CO2 Hydrogenation over a Cu/ZnO/Al2O3 Catalyst

Directory of Open Access Journals (Sweden)

Fereshteh Samimi

2017-11-01

Full Text Available Carbon capture and utilization as a raw material for methanol production are options for addressing energy problems and global warming. However, the commercial methanol synthesis catalyst offers a poor efficiency in CO2 feedstock because of a low conversion of CO2 and its deactivation resulting from high water production during the process. To overcome these barriers, an efficient process consisting of three stage heat exchanger reactors was proposed for CO2 hydrogenation. The catalyst volume in the conventional methanol reactor (CR is divided into three sections to load reactors. The product stream of each reactor is conveyed to a flash drum to remove methanol and water from the unreacted gases (H2, CO and CO2. Then, the gaseous stream enters the top of the next reactor as the inlet feed. This novel configuration increases CO2 conversion almost twice compared to one stage reactor. Also to reduce water production, a water permselective membrane was assisted in each reactor to remove water from the reaction side. The proposed process was compared with one stage reactor and CR from coal and natural gas. Methanol is produced 288, 305, 586 and 569 ton/day in CR, one-stage, three-stage and three-stage membrane reactors (MR, respectively. Although methanol production rate in three-stage MR is a bit lower than three stage reactors, the produced water, as the cause of catalyst poisoning, is notably reduced in this configuration. Results show that the proposed process is a strongly feasible way to produce methanol that can competitive with a traditional synthesis process.

[Isolation of a methanol-utilizing strain and its application for determining methanol].

Science.gov (United States)

Guo, Jun; Gao, Wei; Zhang, Qiang; Qu, Fei; Lu, Dongtao; Zheng, Jun; Pang, Jinmei; Yang, Yujing

2013-08-04

To isolate and characterize bacteria that can be used todevelop microbial biosensor for methanol (MeOH) determination. We used selective medium and streak plate to isolate bacteria. Morphological, physiological characteristics and 16S rDNA sequence analysis were used to identify the strain. An MeOH biosensor was then developed by immobilizing M211 along with dissolved oxygen (O2) sensor. An MeOH utilizing bacterium was isolated from biogas-producing tank using methanol as the sole carbon source, and identified as Methylobacteriumorganophilium. Decrease of O2 concentration is linearly related to the MeOH concentration in the range from 0.02% to 1%, with the MeOH detection limit of 0.27 mg/L. The response time of the biosensor is within 20 min. Furthermore, the result of interference test and the detection of methanol sample are both satisfactory. Good results are obtained in interference test and the detection of methanol sample. The proposed method seems very attractive in monitoring methanol.

Preparation of PtRu/C anode electrocatalysts using gamma radiation for methanol electro-oxidation

International Nuclear Information System (INIS)

Silva, Dionisio Fortunato da

2006-01-01

Pt Ru/C (carbon-supported Pt Ru nanoparticles) anode electrocatalysts were prepared using radiolytic process (gamma radiation) and tested for methanol electro-oxidation. In this process, water/2-propanol and water/ethylene glycol solutions containing the metallic ions and the carbon support were submitted to gamma radiation under stirring. The water/alcohol ratio (v/v) and the total dose (kGy) were studied. A nominal Pt Ru atomic ratio of 50:50 were used in all experiments. The electrocatalysts were characterized by energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD), transmission electron microscopy (TEM) and cyclic voltammetry (CV). The electro-oxidation of methanol was studied by cyclic voltammetry using the thin porous coating technique. The electrocatalysts prepared in water/2-propanol showed crystallite size in the range of 3-5 nm and Pt Ru atomic ratio of 50:50. The electrocatalysts prepared in water/ethylene glycol showed crystallite size (2-3 nm) smaller than the ones obtained in water/2-propanol, however, the Pt Ru atomic ratios obtained were approximately 80:20, showing that only part of ruthenium ions were reduced. For methanol oxidation the electrocatalytic activity depends on the water/2-propanol and water/ethylene glycol ratio used in the reaction medium. The electrocatalysts prepared in water/2-propanol showed inferior performance to the ones prepared in water/ethylene glycol, which showed similar or superior performances (amperes per gram of platinum) to the commercial electrocatalyst from E-TEK. (author)

Dietary methanol and autism.

Science.gov (United States)

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. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Proton conducting hydrocarbon membranes: Performance evaluation for room temperature direct methanol fuel cells

International Nuclear Information System (INIS)

Krivobokov, Ivan M.; Gribov, Evgeniy N.; Okunev, Alexey G.

2011-01-01

The methanol permeability, proton conductivity, water uptake and power densities of direct methanol fuel cells (DMFCs) at room temperature are reported for sulfonated hydrocarbon (sHC) and perfluorinated (PFSA) membranes from Fumatech, and compared to Nafion membranes. The sHC membranes exhibit lower proton conductivity (25-40 mS cm -1 vs. ∼95-40 mS cm -1 for Nafion) as well as lower methanol permeability (1.8-3.9 x 10 -7 cm 2 s -1 vs. 2.4-3.4 x 10 -6 cm 2 s -1 for Nafion). Water uptake was similar for all membranes (18-25 wt%), except for the PFSA membrane (14 wt%). Methanol uptake varied from 67 wt% for Nafion to 17 wt% for PFSA. The power density of Nafion in DMFCs at room temperature decreases with membrane thickness from 26 mW cm -2 for Nafion 117 to 12.5 mW cm -2 for Nafion 112. The maximum power density of the Fumatech membranes ranges from 4 to 13 mW cm -1 . Conventional transport parameters such as membrane selectivity fail to predict membrane performance in DMFCs. Reliable and easily interpretable results are obtained when the power density is plotted as a function of the transport factor (TF), which is the product of proton concentration in the swollen membrane and the methanol flux. At low TF values, cell performance is limited by low proton conductivity, whereas at high TF values it decreases due to methanol crossover. The highest maximum power density corresponds to intermediate values of TF.

Hot new gamble on methanol

Energy Technology Data Exchange (ETDEWEB)

Hatton, J.

1981-10-01

Methanol from coal, wood, or natural gas is being considered as an extender or an alternative source of gasoline. Firms such as Nova and Celanese are gambling millions on the proposition that methanol is a crucial steppingstone to the fuels and chemicals of the future. With a new process developed by Mobil Oil, methanol from coal could be converted into gasoline. By the 1990s Imperial Oil Ltd. expects there will be at least one methanol plant using Alberta coal. These and other plans by the Alberta and British Columbia governments and by Canadian industry to produce methanol are reported.

Sensing methanol concentration in direct methanol fuel cell with total harmonic distortion: Theory and application

International Nuclear Information System (INIS)

Mao Qing; Krewer, Ulrike

2012-01-01

The nonlinear frequency response of a direct methanol fuel cell (DMFC) is studied by analyzing the total harmonic distortion (THD) spectra. The dependence of the THD spectra on methanol concentration and methanol oxidation kinetics is investigated by means of both simulation and experiment. Simulation using a continuous stirred tank reactor network model suggests that the methanol concentration profile in the anode has a strong impact on the THD spectra. The experimentally observed nonlinear behavior of the DMFC anode can be qualitatively reproduced with a model containing a three-step methanol oxidation mechanism with Kauranen–Frumkin/Temkin kinetics. Both experiment and simulation results show that THD value has a monotonic correlation with methanol concentration at certain frequencies and its sensitivity to concentration is improved with increased current amplitude. The monotonic relationship enables the THD to sense the methanol concentration level by the DMFC itself, which is of mayor interest for the portable application as an external sensor for the system can be omitted.

Metabolism of methanol in acetogenic bacteria

International Nuclear Information System (INIS)

Ivey, D.K.W.

1987-01-01

Acetogens can grown on methanol in the presence of a cosubstrate that is more oxidized than methanol. Three mol of acetate is formed from 4 mol methanol and 2 mol CO 2 . One mol of methanol is oxidized to CO 2 . The levels of the tetrahydrofolate enzymes, carbon monoxide dehydrogenase, and corrinoids indicate the presence of the acetyl CoA pathway when growing on methanol. The acetyl-CoA pathway of acetate synthesis as presently understood does not include methanol as a substrate. It is demonstrated that methanol is oxidized to formaldehyde and then to formate by a methanol dehydrogenase. It is also possible that the methyl group of methanol is transferred directly to either a corrinoid-type enzyme, or tetrahydrofolate. When cells of C. thermoautotrophicum are grown on 14 CO 2 , acetate becomes labeled in both carbons with a ratio 14 CH 3 / 14 COOH of 0.7. In addition, methanol gets labeled. When cells are grown on 14 CH 3 OH, label appears in both acetate carbons with a ratio of 3.3, and also appears in CO 2 . Thus methanol is preferentially incorporated into the methyl group of acetate, whereas CO 2 is the preferred source of the carboxyl carbon

Water hammer in complex pipes network: a synthetic method of evaluating the maximum overpressure; Il colpo d`ariete nelle reti: criteri di valutazione degli effetti delle manovre di regolazione

Energy Technology Data Exchange (ETDEWEB)

Bianchi, A. [Milan, Politecnico (Italy). Dip. di Ingegneria Idraulica Ambientale e del Rilevamento; Pasella, G. [Studio di Ingegneria, Arzachena, Sassari (Italy)

1998-07-01

A simplified method for calculating water hammer over pressures in complex pipes networks is presented. The method is valid if cavitation does not arise. The examined networks are the most common in the field of the traditional aqueducts. By means of under dimensioned with respect of the characteristics of the side where the manoeuvre occurs, the authors calculate, with a special computer program and for many different kinds of networks, the maximum over pressure in the branch point of manoeuvre versus manoeuvre time and they observe that it is independent from the complexity of the network itself: it does depend only from the characteristics of the first reflection point and from the head losses in the branch where the manoeuvre occurs. They extend then to the complex networks the traditional formulas for calculating perturbations propagation at the branch points and check their approximation by simulating the same phenomena with the special computer model of the network. By using both results together of the two phases of this research, you can calculate the maximum overpressure at any section of the network. The approximation with respect to the same values calculated with the simulation model is about 5%. It is also demonstrated that the more complex the network, the more damped is the perturbation and the damping effect is already very strong for relatively simple networks. [Italiano] si presenta una metodologia semplificata di calcolo delle sovrapressioni in rete complesse conseguenti a fenomeni di moto vario, valido nei casi in cui nell`evoluzione dei transitori non si verifichino situazioni cavitative. Limitato il campo di indagine ad alcune tipologie di reti aperte che rispecchiano le caratteristiche degli acquedotti tradizionali, adimensionalizzando in funzione delle caratteristiche del lato sede della manovra, si calcola, con un apposito codice di calcolo automatico e per un`ampia casistica di reti, la massima sovrapressione al nodo di manovra in

The Asian methanol market

International Nuclear Information System (INIS)

Nagase, Hideki

1995-01-01

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

Design and Evaluation of a High-Density Energy Storage Route with CO2 Re-Use, Water Electrolysis and Methanol Synthesis

OpenAIRE

Léonard, Grégoire; Giulini, Davide; Villarreal-Singer, Diego

2016-01-01

The energy transition corresponding to more electricity generation from variable and decentralized renewable energy sources requires the development of electricity storage technologies ranging from seconds to seasons. The power-to-fuel process provides a way to store electricity as a liquid energy vector, leading to high energy density and cheap long-term storage at ambient conditions. In the present work, we study the powerto- methanol process combining CO2 capture, water/CO2 ...

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

Energy Technology Data Exchange (ETDEWEB)

Martinez-Guerra, Edith; Gude, Veera Gnaneswar, E-mail: gude@cee.msstate.edu

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.

Taratura di un 'apparecchiatura per misura di piccole percentuali di uranio in soluzione acida di acqua distillata

Directory of Open Access Journals (Sweden)

d. Diana

1965-06-01

Full Text Available Si descrive una tecnica elio permette di misurare ilnumero di atomi di Uranio di una soluzione, con un errore non superioreal 10%.Il sistema consiste in un tubo di Geiger (Philips 18503 sistemato inun contenitore di vetro nel quale viene diluita una certa quantità di peso dinitrato di Uranile, misurato con una precisione migliore dell'1%. Al variaredella diluizione si registra il numero di particelle che il Geiger conta, e quindisi riporta in grafico. Da questi per diverse quantità di sale sciolto si determinala retta di taratura.

On-line methanol sensor system development for recombinant ...

African Journals Online (AJOL)

PANCHIGA

2016-10-19

Oct 19, 2016 ... residual methanol in broth cultures at a constant level. (Guarna et al. ... glycerol and 6.7 ml PTM1 trace salt in deionized water to a total volume of 1 ... rpm for 5 min at 4°C to separate yeast cells from fermented broth. Yeast cell ...

高级醇和烃类化合物含量对甲醇水混溶性的影响%Impact of the Contents of Higher Alcohols and Hydrocarbon Compounds of Methanol upon the Methanol-Water Compatibility

Institute of Scientific and Technical Information of China (English)

牟艳春

2012-01-01

基于工业甲醇中高级醇、烃类化合物与水以一定比例混合后澄清度的差异,在规定的条件下,利用气相色谱法,分析了高级醇、烃类化合物含量的高低对甲醇水混溶性的影响.试验结果表明:高级醇含量增加,甲醇的水混溶性变差;烃类物质含量越高,甲醇的水混溶性越差.%Methanol is an important and widely used raw material in basic organic chemistry. A gas chromatography test was done under specified conditions to show the impact of the amount of higher alcohol and hydrocarbon compounds upon the water compatibility of methanol. The result showed that the existence of higher alcohol and hydrocarbon compounds in methanol makes it not clear, which great affected the quality of the product, besides, it affected the adjustment of the process parameters.

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

Science.gov (United States)

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

2015-04-18

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

Structural insight into the Clostridium difficile ethanolamine utilisation microcompartment.

Directory of Open Access Journals (Sweden)

Alison C Pitts

Full Text Available Bacterial microcompartments form a protective proteinaceous barrier around metabolic enzymes that process unstable or toxic chemical intermediates. The genome of the virulent, multidrug-resistant Clostridium difficile 630 strain contains an operon, eut, encoding a bacterial microcompartment with genes for the breakdown of ethanolamine and its utilisation as a source of reduced nitrogen and carbon. The C. difficile eut operon displays regulatory genetic elements and protein encoding regions in common with homologous loci found in the genomes of other bacteria, including the enteric pathogens Salmonella enterica and Enterococcus faecalis. The crystal structures of two microcompartment shell proteins, CD1908 and CD1918, and an uncharacterised protein with potential enzymatic activity, CD1925, were determined by X-ray crystallography. CD1908 and CD1918 display the same protein fold, though the order of secondary structure elements is permuted in CD1908 and this protein displays an N-terminal β-strand extension. These proteins form hexamers with molecules related by crystallographic and non-crystallographic symmetry. The structure of CD1925 has a cupin β-barrel fold and a putative active site that is distinct from the metal-ion dependent catalytic cupins. Thin-section transmission electron microscopy of Escherichia coli over-expressing eut proteins indicates that CD1918 is capable of self-association into arrays, suggesting an organisational role for CD1918 in the formation of this microcompartment. The work presented provides the basis for further study of the architecture and function of the C. difficile eut microcompartment, its role in metabolism and the wider consequences of intestinal colonisation and virulence in this pathogen.

Single-particle and collective dynamics of methanol confined in carbon nanotubes: a computer simulation study

International Nuclear Information System (INIS)

Garberoglio, Giovanni

2010-01-01

We present the results of computer simulations of methanol confined in carbon nanotubes. Different levels of confinement were identified as a function of the nanotube radius and characterized using a pair-distribution function adapted to the cylindrical geometry of these systems. Dynamical properties of methanol were also analysed as a function of the nanotube size, both at the level of single-particle and collective properties. We found that confinement in narrow carbon nanotubes strongly affects the dynamical properties of methanol with respect to the bulk phase, due to the strong interaction with the carbon nanotube. In the other cases, confined methanol shows properties quite similar to those of the bulk phase. These phenomena are related to the peculiar hydrogen bonded network of methanol and are compared to the behaviour of water confined in similar conditions. The effect of nanotube flexibility on the dynamical properties of confined methanol is also discussed.

Storie di genere, storie di partito

Directory of Open Access Journals (Sweden)

Elisa Bellè

2012-04-01

Full Text Available Lo studio delle narrazioni di genere all'interno di questo tipo di organizzazione desta inoltre un particolare interesse anche in ragione della sottorappresentazione delle donne nella sfera della politica. Si tratta di un deficit democratico che coinvolge i sistemi politici moderni nel loro complesso, ma che interessa l'Italia con una particolare gravità ed evidenza. La questione della sottorappresentazione politica delle donne è stata sinora affrontata prevalentemente in termini tecnico-legali (politiche di pari opportunità ed azione positiva, o di teoria politica (la dicotomia pubblico-maschile e privato-femminile come fondamento del contratto sessuale della politica. Mancano invece contributi che guardino ai partiti come organizzazioni largamente responsabili dei processi di selezione e promozione delle carriere politiche, dunque come luoghi di quotidiana produzione di pratiche e culture di genere, più o meno egualitarie o, viceversa, discriminatorie. Sulla base di tale vuoto di ricerca e riflessione, il presente articolo si propone di mettere in luce le pratiche e le culture di genere che emergono dai racconti di uomini e donne all'interno di due organizzazioni partitiche, una di destra e una di sinistra, situate nel contesto territoriale della provincia di Trento. La ricerca è stata condotta attraverso lo strumento dell'intervista semi-strutturata, coinvolgendo quattro donne e quattro uomini, divisi per coppie di età (un uomo ed una donna giovani ed un uomo ed una donna da lungo presenti nel partito, accostabili per quanto concerne ruolo e posizione nelle organizzazioni partitiche considerate. L'attenzione analitica si è concentrata sulla costruzione del genere di uomini e donne intervistati/e, intesa sia come dimensione ed esperienza individuale (le storie di genere dei/lle singoli/e, sia come dimensione organizzativa più ampia (le storie di genere delle organizzazioni, narrate dalle diverse voci. Un'ulteriore dimensione analitica

Endogenous Methanol Regulates Mammalian Gene Activity

Science.gov (United States)

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

2014-01-01

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

Endogenous methanol regulates mammalian gene activity.

Directory of Open Access Journals (Sweden)

Tatiana V Komarova

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

Developments in the European methanol market

International Nuclear Information System (INIS)

Speed, J.

1995-01-01

In the late eighties/early nineties the World Methanol Market was basically divided into three regional markets--America, Asia Pacific and Europe. These markets were interrelated but each had its own specific characteristics and traditional suppliers. Now the situation has changed; in the mid nineties there is a Global Methanol Market with global players and effective global pricing and the European market is governed by events world-wide. Europe is however a specific market with specific characteristics which are different from those of other markets although it is also part of the Global Market. Hence before the author focuses on Europe he looks at the World Market. The paper discusses world methanol production and consumption by region, world methanol consumption by end use, world methanol supply demand balance, the west European market, western European methanol production, methanol imports to W. Europe, the Former Soviet Union supplies, W. European methanol consumption by end use, MTBE in Europe, duties on methanol imports into W. Europe, investment in Europe, the effect of the 1994/95 price spike, and key issues for the future of the industry

Micro-electro-mechanical systems (MEMS)-based micro-scale direct methanol fuel cell development

International Nuclear Information System (INIS)

Yao, S.-C.; Tang Xudong; Hsieh, C.-C.; Alyousef, Yousef; Vladimer, Michael; Fedder, Gary K.; Amon, Cristina H.

2006-01-01

This paper describes a high-power density, silicon-based micro-scale direct methanol fuel cell (DMFC), under development at Carnegie Mellon. Major issues in the DMFC design include the water management and energy-efficient micro fluidic sub-systems. The air flow and the methanol circulation are both at a natural draft, while a passive liquid-gas separator removes CO 2 from the methanol chamber. An effective approach for maximizing the DMFC energy density, pumping the excess water back to the anode, is illustrated. The proposed DMFC contains several unique features: a silicon wafer with arrays of etched holes selectively coated with a non-wetting agent for collecting water at the cathode; a silicon membrane micro pump for pumping the collected water back to the anode; and a passive liquid-gas separator for CO 2 removal. All of these silicon-based components are fabricated using micro-electro-mechanical systems (MEMS)-based processes on the same silicon wafer, so that interconnections are eliminated, and integration efforts as well as post-fabrication costs are both minimized. The resulting fuel cell has an overall size of one cubic inch, produces a net output of 10 mW, and has an energy density three to five times higher than that of current lithium-ion batteries

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

International Nuclear Information System (INIS)

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

2011-01-01

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.

New Catalysts for Direct Methanol Oxidation Fuel Cells

Energy Technology Data Exchange (ETDEWEB)

Adzic, Radoslav

1998-08-01

A new class of efficient electrocatalytic materials based on platinum - metal oxide systems has been synthetized and characterized by several techniques. Best activity was found with NiWO{sub 4}-, CoWO{sub 4}-, and RuO{sub 2}- sr¡pported platinum catalysts. A very similar activity at room temperature was observed with the electrodes prepared with the catalyst obtained from International Fuel Cells Inc. for the same Pt loading. Surprisingly, the two tungstates per se show a small activity for methanol oxidation without any Pt loading. Synthesis of NiWO{sub 4} and CoWO{sub 4} were carried out by solid-state reactions. FTIR spectroscopy shows that the tungstates contain a certain amount of physically adsorbed water even after heating samples at 200{degrees}C. A direct relationship between the activity for methanol oxidation and the amount of adsorbed water on those oxides has been found. The Ru(0001) single crystal shows a very small activity for CO adsorption and oxidation, in contrast to the behavior of polycrystalline Ru. In situ extended x-ray absorption fine structure spectroscopy (EXAFS) and x-ray absorption near edge spectroscopy (XANES) showed that the OH adsorption on Ru in the Pt-Ru alloy appears to be the limiting step in methanol oxidation. This does not occur for Pt-RuO{SUB 2} electrocatalyst, which explains its advantages over the Pt-Ru alloys. The IFCC electrocatalyst has the properties of the Pt-Ru alloy.

Experimental study to distinguish the effects of methanol slip and water vapour on a high temperature PEM fuel cell at different operating conditions

DEFF Research Database (Denmark)

Thomas, Sobi; Vang, Jakob Rabjerg; Araya, Samuel Simon

2017-01-01

The objective of this paper is to separate out the effects of methanol and water vapour on a high temperature polymer electrolyte membrane fuel cell under different temperatures (160°C and 180°C) and current densities (0.2Acm-2, 0.4Acm-2 and 0.6Acm-2). The degradation rates at the different curre...

Sensor-less control of the methanol concentration of direct methanol fuel cells at varying ambient temperatures

International Nuclear Information System (INIS)

An, Myung-Gi; Mehmood, Asad; Ha, Heung Yong

2014-01-01

Highlights: • A new algorithm is proposed for the sensor-less control of methanol concentration. • Two different strategies are used depending on the ambient temperatures. • Energy efficiency of the DMFC system has been improved by using the new algorithm. - Abstract: A new version of an algorithm is used to control the methanol concentration in the feed of DMFC systems without using methanol sensors under varying ambient temperatures. The methanol concentration is controlled indirectly by controlling the temperature of the DMFC stack, which correlates well with the methanol concentration. Depending on the ambient temperature relative to a preset reference temperature, two different strategies are used to control the stack temperature: either reducing the cooling rate of the methanol solution passing through an anode-side heat exchanger; or, lowering the pumping rate of the pure methanol to the depleted feed solution. The feasibility of the algorithm is evaluated using a DMFC system that consists of a 200 W stack and the balance of plant (BOP). The DMFC system includes a sensor-less methanol controller that is operated using a LabView system as the central processing unit. The algorithm is experimentally confirmed to precisely control the methanol concentration and the stack temperature at target values under an environment of varying ambient temperatures

Enthalpies of solvation of ethylene oxide oligomers CH{sub 3}O(CH{sub 2}CH{sub 2}O){sub n}CH{sub 3} (n = 1 to 4) in different H-bonding solvents: Methanol, chloroform, and water. Group contribution method as applied to the polar oligomers

Energy Technology Data Exchange (ETDEWEB)

Barannikov, Vladimir P., E-mail: vpb@isc-ras.ru [Institute of Solution Chemistry, Russian Academy of Sciences, Academicheskaya Str. 1, Ivanovo 153045 (Russian Federation); Guseynov, Sabir S.; Vyugin, Anatoliy I. [Institute of Solution Chemistry, Russian Academy of Sciences, Academicheskaya Str. 1, Ivanovo 153045 (Russian Federation)

2011-12-15

Highlights: > Solvation enthalpy is found for ethylene oxide oligomers in chloroform and methanol. > Coefficients of solute-solute interaction are determined for oligomers in methanol. > Enthalpies of hydrogen bonding of oligomers with chloroform and water are estimated. > Additivity scheme is developed for describing enthalpies of solvation of oligomers. - Abstract: The enthalpies of solution and solvation of ethylene oxide oligomers CH{sub 3}O(CH{sub 2}CH{sub 2}O){sub n}CH{sub 3} (n = 1 to 4) in methanol and chloroform have been determined from calorimetric measurements at T = 298.15 K. The enthalpic coefficients of pairwise solute-solute interaction for methanol solutions have been calculated. The enthalpic characteristics of the oligomers in methanol, chloroform, water and tetrachloromethane have been compared. The hydrogen bonding of the oligomers with chloroform and water molecules is exhibited in the values of solvation enthalpy and coefficient of solute-solute interaction. This effect is not observed for methanol solvent. The thermochemical data evidence an existence of multi-centred hydrogen bonds in associates of polyethers with the solvent molecules. Enthalpies of hydrogen bonding of the oligomers with chloroform and water have been estimated. The additivity scheme has been developed to describe the enthalpies of solvation of ethylene oxide oligomers, unbranched monoethers and n-alkanes in chloroform, methanol, water, and tetrachloromethane. The correction parameters for contribution of repeated polar groups and correction term for methoxy-compounds have been introduced. The obtained group contributions permit to describe the enthalpies of solvation of unbranched monoethers and ethylene oxide oligomers in the solvents with standard deviation up to 0.6 kJ . mol{sup -1}. The values of group contributions and corrections are strongly influenced by solvent properties.

A novel multiple headspace extraction gas chromatographic method for measuring the diffusion coefficient of methanol in water and in olive oil.

Science.gov (United States)

Zhang, Chun-Yun; Chai, Xin-Sheng

2015-03-13

A novel method for the determination of the diffusion coefficient (D) of methanol in water and olive oil has been developed. Based on multiple headspace extraction gas chromatography (MHE-GC), the methanol released from the liquid sample of interest in a closed sample vial was determined in a stepwise fashion. A theoretical model was derived to establish the relationship between the diffusion coefficient and the GC signals from MHE-GC measurements. The results showed that the present method has an excellent precision (RSDwater and olive oil, when compared with data reported in the literature. The present method is simple and practical and can be a valuable tool for the determination of the diffusion coefficient of volatile analyte(s) into food simulants from food and beverage packaging material, both in research studies and in actual applications. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparative study of hydrogen and methanol as energy carriers

Energy Technology Data Exchange (ETDEWEB)

Johansson, Anna

1998-06-01

This report has been written with the purpose to compare hydrogen and methanol, with gasoline, as energy carriers for new energy systems in the future. This energy system must satisfy the demands for sustainable development. The report focuses on motor vehicle applications. A few different criteria has been developed to help form the characterisation method. The criteria proposed in this thesis are developed for an environmental comparison mainly based on emissions from combustion. The criteria concerns the following areas: Renewable resources, The ozone layer, The greenhouse effect, The acidification, and Toxic substances. In many ways, hydrogen may seem as a very good alternative compared with gasoline and diesel oil. Combustion of hydrogen in air results in water and small amounts of oxides of nitrogen. In this report, hydrogen produced from renewable resources is investigated. This is necessary to fulfill the demands for sustainable development. Today, however, steam reforming of fossil fuels represent 99% of the hydrogen production market. Problem areas connected with hydrogen use are for instance storage and distribution. Methanol has many advantages, while comparing methanol and gasoline, like lower emissions of nitrogen oxides and hydrocarbons, limited emissions of carbon dioxide and no sulphur content. Methanol can be produced from many different resources, for example natural gas, naphtha, oil, coal or peat, and biomass. To meet demands for sustainable production, methanol has to be produced from biomass Examination paper. 32 refs, 20 figs, 13 tabs

Ruthenium–Platinum Catalysts and Direct Methanol Fuel Cells (DMFC: A Review of Theoretical and Experimental Breakthroughs

Directory of Open Access Journals (Sweden)

Ana S. Moura

2017-02-01

Full Text Available The increasing miniaturization of devices creates the need for adequate power sources and direct methanol fuel cells (DMFC are a strong option in the various possibilities under current development. DMFC catalysts are mostly based on platinum, for its outperformance in three key areas (activity, selectivity and stability within methanol oxidation framework. However, platinum poisoning with products of methanol oxidation led to the use of alloys. Ruthenium–platinum alloys are preferred catalysts active phases for methanol oxidation from an industrial point of view and, indeed, ruthenium itself is a viable catalyst for this reaction. In addition, the route of methanol decomposition is crucial in the goal of producing H2 from water reaction with methanol. However, the reaction pathway remains elusive and new approaches, namely in computational methods, have been ensued to determine it. This article reviews the various recent theoretical approaches for determining the pathway of methanol decomposition, and systematizes their validation with experimental data, within methodological context.

A Systematic Approach for Conceptual and Sustainable Process Design: Production of Methylamines From Methanol and Ammonia

DEFF Research Database (Denmark)

Mansouri, Seyed Soheil; Ismail, Muhammad Imran Bin; Almoor, Karim

2012-01-01

and environmentally acceptable plant for producing mono-methylamines, di-methylamines and tri-methylamines from methanol and ammonia. The systematic method divides the process design work into 12 sequential tasks that covers all stages of conceptual design, starting from the consideration of qualitative aspects...... of the process flow sheet and preliminary calculations to the detailed process simulations, equipment sizing, costing, an economic evaluation, and sustainability of the designed process. At the end of task-9, the base case design is obtained, which is then further refined and improved with respect to heat...

Thermophysical properties of biodiesel and related systems. Part I. Vapour–liquid equilibrium at low pressures of binary and ternary systems involving methanol, ethanol, glycerol, water and NaCl

International Nuclear Information System (INIS)

Veneral, Josamaique G.; Benazzi, Tassio; Mazutti, Marcio A.; Voll, Fernando A.P.; Cardozo-Filho, Lúcio; Corazza, Marcos L.; Guirardello, Reginaldo; Vladimir Oliveira, J.

2013-01-01

Highlights: ► Experimental vapour–liquid equilibrium data of multicomponent mixtures of biodiesel-related systems. ► Othmer-type ebulliometer in the pressure range of 6.7 to 66.7 kPa. ► Experimental data satisfactorily represented by the UNIQUAC model. -- Abstract: Experimental vapour–liquid equilibrium data of several binary mixtures (methanol + glycerol), (ethanol + glycerol) and (glycerol + water) and ternary (methanol + glycerol + water), (ethanol + glycerol + water) and (water + glycerol + NaCl) were obtained over the pressure range of 6.7 kPa to 66.7 kPa through an Othmer-type ebulliometer, allowing the construction of temperature – mass fraction and pressure – temperature diagrams. It is shown that the systems without NaCl were satisfactorily represented by the UNIQUAC model with good agreement between theory and experimental results. It was observed that alcohol concentrations lower than 10 wt% increase the phase transition temperature. The systems investigated show positive deviations in relation to Raoult’s law. Results presented in this work may be relevant in process design towards efficient recovering of components in the biodiesel down-stream processes

Generation of gaseous methanol reference standards

International Nuclear Information System (INIS)

Geib, R.C.

1991-01-01

Methanol has been proposed as an automotive fuel component. Reliable, accurate methanol standards are essential to support widespread monitoring programs. The monitoring programs may include quantification of methanol from tailpipe emissions, evaporative emissions, plus ambient air methanol measurements. This paper will present approaches and results in the author's investigation to develop high accuracy methanol standards. The variables upon which the authors will report results are as follows: (1) stability of methanol gas standards, the studies will focus on preparation requirements and stability results from 10 to 1,000 ppmv; (2) cylinder to instrument delivery system components and purge technique, these studies have dealt with materials in contact with the sample stream plus static versus flow injection; (3) optimization of gas chromatographic analytical system will be discussed; (4) gas chromatography and process analyzer results and utility for methanol analysis will be presented; (5) the accuracy of the methanol standards will be qualified using data from multiple studies including: (a) gravimetric preparation; (b) linearity studies; (c) independent standards sources such as low pressure containers and diffusion tubes. The accuracy will be provided as a propagation of error from multiple sources. The methanol target concentrations will be 10 to 500 ppmv

Methanol from biomass: A technoeconomic analysis

International Nuclear Information System (INIS)

Stevens, D.J.

1991-01-01

Biomass-derived methanol offers significant potential as an alternative transportation fuel. Methanol is cleaner burning and has a lower flame temperature than gasoline. These characteristics can result in lower carbon monoxide and nitrogen oxide emissions when methanol is used as a fuel. Methanol produced from biomass offers potential advantages over that from other sources. When produced from biomass which is subsequently regrown, methanol does not contribute net emissions of carbon dioxide, a greenhouse gas, to the atmosphere. The introduction of alternative fuels will likely be driven by a number of political and economic decisions. The ability of biomass to compete with other resources will be determined in part by the economics of the production systems. In this paper, recent technoeconomic analyses of biomass-methanol systems are presented. The results are compared with methanol production from coal and natural gas

KERENTANAN PENYUSUPAN AIR LAUT DI PESISIR UTARA PULAU TERNATE (Vulnerability of Sea Water Intrusion in Northern Coastal of Ternate Island

Directory of Open Access Journals (Sweden)

Rahim Achmad

2016-07-01

Full Text Available ABSTRAK Penelitian ini dilakukan di wilayah pesisir bagian utara Pulau Ternate, dengan tujuan mengetahui kedalaman batas kontak airtanah dengan air laut dan menganalisis akuifer serta cara pengambilan airtanah sehingga tidak terjadi penyusupan air laut ke dalam tubuh airtanah. Sampel air sumur diukur untuk mengetahui kadar salinitas dan daya hantar listrik (DHL. Kedalaman batas kontak airtanah dengan air laut dukur dengan menggunakan metode geolistrik. Hasil pengukuran DHL dan salinitas airtanah di wilayah pesisir utara menunjukkan, terdapat penyusupan air laut di Desa Tobolo dan Sulamadaha, dengan rentang nilai masing-masing antara 0,5-3,3 mS/cm dan 0,2-1,7 ppt. Hasil pengukuran geolistrik menunjukkan batas kontak airtanah dengan air laut rata-rata antara 12-15 m dari permukaan. Nilai resistivitas air laut berkisar antara 0,01-20 Ωm. Hasil penelitian ini memberikan peringatan untuk tidak melakukan pengeboran sumur di wilayah pesisir. Sebagai contoh kasus, pengeboran sumur hingga 80 m dengan jarak sekitar 250 m dari garis pantai di Desa Takome, di mana batas kontak airtanah dengan air laut pada kedalaman 15 m. Pengukuran nilai DHL dan salinatas air dari sumur ini menunjukkan masing-masing 6,1 mS/cm dan 3,3 ppt. Nilai ini menunjukkan kedalaman sumur bor telah melewati zona pencampuran antara airtanah dengan air laut (interface.   ABSTRACT This research was conducted in the coastal areas of northern part of Ternate island, in order to know the depth of interface and to analyze the aquifers and to avoid seawater intrusion caused of groundwater extraction. Well water samples were measured to determine levels of salinity and DHL. The depth of interface was measured using geoelectric method. The results of electrical conductivity (EC and salinity of groundwater measurement in the northern coastal area showed that, there is infiltration of sea water in Tobolo and Sulamadaha. The EC and salinity values ranging between 0.5-3.3 mS/cm and 0.2-1.7 ppt

Catalytic methanol dissociation

International Nuclear Information System (INIS)

Alcinikov, Y.; Fainberg, V.; Garbar, A.; Gutman, M.; Hetsroni, G.; Shindler, Y.; Tatrtakovsky, L.; Zvirin, Y.

1998-01-01

Results of the methanol dissociation study on copper/potassium catalyst with alumina support at various temperatures are presented. The following gaseous and liquid products at. The catalytic methanol dissociation is obtained: hydrogen, carbon monoxide, carbon dioxide, methane, and dimethyl ether. Formation rates of these products are discussed. Activation energies of corresponding reactions are calculated

Application of flexible micro temperature sensor in oxidative steam reforming by a methanol micro reformer.

Science.gov (United States)

Lee, Chi-Yuan; Lee, Shuo-Jen; Shen, Chia-Chieh; Yeh, Chuin-Tih; Chang, Chi-Chung; Lo, Yi-Man

2011-01-01

Advances in fuel cell applications reflect the ability of reformers to produce hydrogen. This work presents a flexible micro temperature sensor that is fabricated based on micro-electro-mechanical systems (MEMS) technology and integrated into a flat micro methanol reformer to observe the conditions inside that reformer. The micro temperature sensor has higher accuracy and sensitivity than a conventionally adopted thermocouple. Despite various micro temperature sensor applications, integrated micro reformers are still relatively new. This work proposes a novel method for integrating micro methanol reformers and micro temperature sensors, subsequently increasing the methanol conversion rate and the hydrogen production rate by varying the fuel supply rate and the water/methanol ratio. Importantly, the proposed micro temperature sensor adequately controls the interior temperature during oxidative steam reforming of methanol (OSRM), with the relevant parameters optimized as well.

Application of Flexible Micro Temperature Sensor in Oxidative Steam Reforming by a Methanol Micro Reformer

Directory of Open Access Journals (Sweden)

Yi-Man Lo

2011-02-01

Full Text Available Advances in fuel cell applications reflect the ability of reformers to produce hydrogen. This work presents a flexible micro temperature sensor that is fabricated based on micro-electro-mechanical systems (MEMS technology and integrated into a flat micro methanol reformer to observe the conditions inside that reformer. The micro temperature sensor has higher accuracy and sensitivity than a conventionally adopted thermocouple. Despite various micro temperature sensor applications, integrated micro reformers are still relatively new. This work proposes a novel method for integrating micro methanol reformers and micro temperature sensors, subsequently increasing the methanol conversion rate and the hydrogen production rate by varying the fuel supply rate and the water/methanol ratio. Importantly, the proposed micro temperature sensor adequately controls the interior temperature during oxidative steam reforming of methanol (OSRM, with the relevant parameters optimized as well.

OCTANOL/WATER PARTITION COEFFICIENTS AND WATER SOLUBILITIES OF PHTHALATE ESTERS

Science.gov (United States)

Measurements of the octanol/water partition coefficients (K-ow) and water solubilities of di-n-octyl phthalate (DnOP) and di-n-decyl phthalate (DnDP) by the slow-stirring method are reported. The water solubility was also measured for di-n-hexyl phthalate (DnHP). The log K-ow val...

Methanol as an energy carrier

Energy Technology Data Exchange (ETDEWEB)

Biedermann, P.; Grube, T.; Hoehlein, B. (eds.)

2006-07-01

For the future, a strongly growing energy demand is expected in the transport sector worldwide. Economically efficient oil production will run through a maximum in the next decade. Higher fuel prices and an environmentally desirable reduction of emissions will increase the pressure for reducing fuel consumption and emissions in road traffic. These criteria show the urgent necessity of structural changes in the fuel market. Due to its advantages concerning industrial-scale production, storage and global availability, methanol has the short- to medium-term potential for gaining increased significance as a substitution product in the energy market. Methanol can be produced both from fossil energy sources and from biomass or waste materials through the process steps of synthesis gas generation with subsequent methanol synthesis. Methanol has the potential to be used in an environmentally friendly manner in gasoline/methanol mixtures for flexible fuel vehicles with internal combustion engines and in diesel engines with pure methanol. Furthermore, it can be used in fuel cell vehicles with on-board hydrogen production in direct methanol fuel cell drives, and in stationary systems for electricity and heat generation as well as for hydrogen production. Finally, in portable applications it serves as an energy carrier for electric power generation. In this book, the processes for the production and use of methanol are presented and evaluated, markets and future options are discussed and issues of safety and environmental impacts are addressed by a team of well-known authors. (orig.)

Separation of xylose oligomers using centrifugal partition chromatography with a butanol-methanol-water system.

Science.gov (United States)

Lau, Ching-Shuan; Clausen, Edgar C; Lay, Jackson O; Gidden, Jennifer; Carrier, Danielle Julie

2013-01-01

Xylose oligomers are the intermediate products of xylan depolymerization into xylose monomers. An understanding of xylan depolymerization kinetics is important to improve the conversion of xylan into monomeric xylose and to minimize the formation of inhibitory products, thereby reducing ethanol production costs. The study of xylan depolymerization requires copious amount of xylose oligomers, which are expensive if acquired commercially. Our approach consisted of producing in-house oligomer material. To this end, birchwood xylan was used as the starting material and hydrolyzed in hot water at 200 °C for 60 min with a 4 % solids loading. The mixture of xylose oligomers was subsequently fractionated by a centrifugal partition chromatography (CPC) with a solvent system of butanol:methanol:water in a 5:1:4 volumetric ratio. Operating in an ascending mode, the butanol-rich upper phase (the mobile phase) eluted xylose oligomers from the water-rich stationary phase at a 4.89 mL/min flow rate for a total fractionation time of 300 min. The elution of xylose oligomers occurred between 110 and 280 min. The yields and purities of xylobiose (DP 2), xylotriose (DP 3), xylotetraose (DP 4), and xylopentaose (DP 5) were 21, 10, 14, and 15 mg/g xylan and 95, 90, 89, and 68 %, respectively. The purities of xylose oligomers from this solvent system were higher than those reported previously using tetrahydrofuran:dimethyl sulfoxide:water in a 6:1:3 volumetric ratio. Moreover, the butanol-based solvent system improved overall procedures by facilitating the evaporation of the solvents from the CPC fractions, rendering the purification process more efficient.

Phase equilibria modeling of methanol-containing systems with the CPA and sPC-SAFT equations of state

DEFF Research Database (Denmark)

Tybjerg, Peter Chr. V.; Kontogeorgis, Georgios; Michelsen, Michael Locht

2010-01-01

Proper representation at various conditions of phase equilibria of methanol-containing mixtures (with hydrocarbons, water, etc.) is Important for oil flow assurance purposes In this work two association equations of state. CPA and sPC-SAFT, are applied to methanol-containing mixtures The purpose ...

Characterization and Modeling of a Methanol Reforming Fuel Cell System

DEFF Research Database (Denmark)

Sahlin, Simon Lennart

topologies is the Reformed Methanol Fuel Cell (RMFC) system that operates on a mix of methanol and water. The fuel is reformed with a steam reforming to a hydrogen rich gas, however with additional formation of Carbon Monoxide and Carbon Dioxide. High Temperature Polymer Electrolyte Membrane Fuel Cell (HT...... to heat up the steam reforming process. However, utilizing the excess hydrogen in the system complicates the RMFC system as the amount of hydrogen can vary depending on the fuel methanol supply, fuel cell load and the reformer gas composition. This PhD study has therefore been involved in investigating......Many fuel cells systems today are operated with compressed hydrogen which has great benefits because of the purity of the hydrogen and the relatively simple storage of the fuel. However, compressed hydrogen is stored in the range of 800 bar, which can be expensive to compress.One of the interesting...

Esterification kinetics of free fatty acids with supercritical methanol for biodiesel production

International Nuclear Information System (INIS)

Alenezi, R.; Leeke, G.A.; Winterbottom, J.M.; Santos, R.C.D.; Khan, A.R.

2010-01-01

Non-catalytic esterification of Free Fatty Acids (FFA) with supercritical methanol was studied under reaction conditions of (250-320 deg. C) at 10 MPa. A detailed experimental programme was implemented to investigate the influence of temperature, stirring rate and the molar ratio of methanol to FFA in the feed in a batch-type reaction vessel. The esterification products of FFA with supercritical methanol are Fatty Acids Methyl Esters (FAME; biodiesel) and water. The yield of FAME was found to increase with an increase in temperature, and with an increase in the molar ratio of methanol to FFA. At >850 rpm the yield of FAME was not affected by stirring rate. The rate constants and energy of activation have been numerically evaluated by solving an ordinary differential equation that describes the reaction kinetics. The proposed kinetic model shows a reversible second order reaction and represents all the experimental data satisfactorily, providing deeper insight into the kinetics of the reaction.

Methanol and ethanol vapor conversion in gas discharge with strongly non-uniform distribution of electric field on atmospheric pressure

International Nuclear Information System (INIS)

Golota, V.I.; Zavada, L.M.; Kotyukov, O.V.; Kudin, D.V.; Rodionov, S.V.; Pis'menetskoj, A.S.; Dotsenko, Yu.V.

2010-01-01

The barrierless gas discharge of negative polarity with strongly non-uniform distribution of electrical field in the methanol and ethanol vapour was studied. It is shown that level of methanol and ethanol conversion depended from power consumed by the discharge and exposition time for gas mixture in discharge zone. The condition for deep conversion of the methanol and ethanol vapours were determined. The water and carbon dioxide are the end products for the methanol and ethanol conversion. Formaldehyde and formic acid are the intermediates products in the conversion of methanol. And ethanol has a number of different compounds, including acetic acid, acetaldehyde, etc.

Antidiuretic Activity of the Methanol Extract of Aporusa lindleyana ...

African Journals Online (AJOL)

Methods: Three doses (500, 1000 and 1500 mg/kg) of the methanol extract (ME) of Aporusa lindleyana (Leaf and bark in 5:1 ratio) were orally administered to female, adult Sprague Dawley rats. Furosemide, vasopressin (antidiuretic hormone) and distilled water were used as diuretic reference, antidiuretic reference and ...

Liquid-Feed Methanol Fuel Cell With Membrane Electrolyte

Science.gov (United States)

Surampudi, Subbarao; Narayanan, S. R.; Halpert, Gerald; Frank, Harvey; Vamos, Eugene

1995-01-01

Fuel cell generates electricity from direct liquid feed stream of methanol/water solution circulated in contact with anode, plus direct gaseous feed stream of air or oxygen in contact with cathode. Advantages include relative simplicity and elimination of corrosive electrolytic solutions. Offers potential for reductions in size, weight, and complexity, and for increases in safety of fuel-cell systems.

Enzymatic hydrolysis of wood. III. Pretreatment of woods with acidic methanol-water mixture

Energy Technology Data Exchange (ETDEWEB)

Shimizu, K; Usami, K

1980-01-01

Wood meal of Pinus densiflora (I) and Fagus crenata (II) was heated in aqueous methanol containing 0.1-0.6% HCl for 15-90 minutes at 120-170 degrees Centigrade to remove lignin and hydrolyse hemicelluloses. About 75% of the lignin could be removed from (I) and 90% from (II) under appropriate conditions. The cellulosic residues were hydrolysed with Trichoderma viride; it was necessary to remove more than 70% of the lignin from (I) and 80% from (II) for complete hydrolysis of the cellulose. Lignin was precipitated from the hydrolysis liquor by distilling off the methanol. The effects of composition of the MeOH-H/sub 2/O mixture, temperature, reaction time and HC1 concentration were studied.

Operation characteristic analysis of a direct methanol fuel cell system using the methanol sensor-less control method

Energy Technology Data Exchange (ETDEWEB)

Chen, C.Y.; Chang, C.L. [Institute of Nuclear Energy Research (INER), Longtan Township, Taoyuan County (China); Sung, C.C. [National Taiwan University (China)

2012-10-15

The application of methanol sensor-less control in a direct methanol fuel cell (DMFC) system eliminates most of the problems encountered when using a methanol sensor and is one of the major solutions currently used in commercial DMFCs. This study focuses on analyzing the effect of the operating characteristics of a DMFC system on its performance under the methanol sensor-less control as developed by Institute of Nuclear Energy Research (INER). Notably, the influence of the dispersion of the methanol injected on the behavior of the system is investigated systematically. In addition, the mechanism of the methanol sensor-less control is investigated by varying factors such as the timing of the injection of methanol, the cathode flow rate, and the anode inlet temperature. These results not only provide insight into the mechanism of methanol sensor-less control but can also aid in the improvement and application of DMFC systems in portable and low-power transportation. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Dai bisogni di salute al consumo di risorse sanitarie in provincia di Bergamo: profilo degli indicatori di bisogno, domanda, offerta

Directory of Open Access Journals (Sweden)

A. Zucchi

2003-05-01

Full Text Available

Introduzione: la complessità interpretativa dei dati relativi ad alcuni fenomeni sanitari a livello territoriale impone la necessità di uno strumento semplice di lettura “epidemiologica”; tale lettura si fonda sull’utilizzo di una serie di “indicatori”, fondamenta di un processo dinamico di monitoraggio temporale e spaziale in grado di descrivere sinteticamente fenomeni di per sé complessi, al fine di fornire al decisore un supporto sintetico ma scientificamente solido.

Obiettivi: istituzione di un sistema di monitoraggio sanitario community-based; definizione di indicatori sanitari comparabili tramite un esame critico dei dati esistenti; sviluppo di metodologie per la raccolta e la validazione dei dati; supporto alla creazione di un sistema efficace e affidabile di trasferimento e scambio dei dati e degli indicatori stessi con uso spinto della tecnologia telematica; elaborazione di metodi e di strumenti necessari alla produzione di analisi e relazioni.

Materiali e metodi: gli indicatori analizzati fanno riferimento
all’elenco definito dal decreto ministeriale n. 27 del 12 dicembre 2001 “sistema di garanzie per il monitoraggio dell’assistenza sanitaria”. A questo elenco ne sono stati aggiunti altri, per un totale di 127, divisi in grandi capitoli tematici: assistenza sanitaria, assistenza distrettuale, assistenza ospedaliera, indicatori stato di salute, consumo di risorse sanitarie (cui è stato dato particolare enfasi, indicatori di domanda/accessibilità. Per definire infine un
profilo di sintesi di questi grandi capitoli e delle relative
eterogeneità territoriali si è successivamente applicata la tecnica statistica dello “z-score”.
Risultati: le differenze emerse a livello distrettuale hanno permesso di disegnare una ‘mappa’ degli indicatori sanitari in provincia di Bergamo.

Conclusioni:i risultati di

Study of SI engine fueled with methanol vapor and dissociation gas based on exhaust heat dissociating methanol

International Nuclear Information System (INIS)

Fu, Jianqin; Deng, Banglin; Liu, Jingping; Wang, Linjun; Xu, Zhengxin; Yang, Jing; Shu, Gequn

2014-01-01

Highlights: • The full load power decreases successively from gasoline engine, methanol vapor engine to dissociated methanol engine. • Both power and thermal efficiency of dissociated methanol engine can be improved by boosting pressure. • The conversion efficiency of recovered exhaust gas energy is largely influenced by the BMEP. • At the same BMEP, dissociated methanol engine has higher thermal efficiency than methanol vapor engine and gasoline engine. - Abstract: To improve the fuel efficiency of internal combustion (IC) engine and also achieve the goal of direct usage of methanol fuel on IC engine, an approach of exhaust heat dissociating methanol was investigated, which is a kind of method for IC engine exhaust heat recovery (EHR). A bottom cycle system is coupled with the IC engine exhaust system, which uses the exhaust heat to evaporate and dissociate methanol in its catalytic cracker. The methanol dissociation gas (including methanol vapor) is used as the fuel for IC engine. This approach was applied to both naturally aspirated (NA) engine and turbocharged engine, and the engine performance parameters were predicted by the software GT-power under various kinds of operating conditions. The improvement to IC engine performance and the conversion efficiency of recovered exhaust gas energy can be evaluated by comparing the performances of IC engine fueled with various kinds of fuels (or their compositions). Results show that, from gasoline engine, methanol vapor engine to dissociated methanol engine, the full load power decreases successively in the entire speed area due to the declining of volumetric efficiency, while it is contrary in the thermal efficiency at the same brake mean effective pressure (BMEP) level because of the improving of fuel heating value. With the increase of BMEP, the conversion efficiency of recovered exhaust gas energy is promoted. All those results indicate that the approach of exhaust heat dissociating methanol has large

Modifications for use of methanol or methanol-gasoline blends in automotive vehicles, September 1976-January 1980

Energy Technology Data Exchange (ETDEWEB)

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.

Catalytic performance of heterogeneous Rh/C3N4 for the carbonylation of methanol

Science.gov (United States)

Budiman, Anatta Wahyu; Choi, Myoung Jae; Nur, Adrian

2018-02-01

The excess of water in homogeneous the carbonylation of methanol system could increase the amount of by-products formed through water-gas shift reaction and could accelerate the rusting of equipment. Many scientists tried to decrease the content of water in the carbonylation of methanol system by using lithium and iodide promoter that results a moderate catalytic activity in the water content at 2wt%. The heterogenized catalyst offers several distinct advantages such as it was enables increased catalyst concentration in the reaction mixture, which is directly proportional to acetic acid production rate, without the addition of an alkali iodide salt promoter. The heterogeneous catalyst also results in reduced by-product formation. This study is aimed to produce a novel catalyst (Rh/C3N4) with a high selectivity of acetic acid in a relatively lower water and halide content. This novel catalyst performs high conversion and selectivity of acetic acid as the result of the strong ionic bonding of melamine and rhodium complex species that was caused by the presence of methyl iodide species. The CO2 in feed gas significantly decreases the catalytic activity of Rh-melamine because of its inert characteristics. The kinetic test was performed as that the first order kinetic equation. The kinetic tests revealed the reaction route of the the carbonylation of methanol in this system was performed trough the methyl acetate.

Thermodynamics of R-(+)-2-(4-Hydroxyphenoxy)propanoic Acid Dissolution in Methanol, Ethanol, and Methanol-Ethanol Mixture

Science.gov (United States)

Liu, Wei; Ma, Jinju; Yao, Xinding; Fang, Ruina; Cheng, Liang

2018-05-01

The solubilities of R-(+)-2-(4-hydroxyphenoxy)propanoic acid (D-HPPA) in methanol, ethanol and various methanol-ethanol mixtures are determined in the temperature range from 273.15 to 323.15 K at atmospheric pressure using a laser detecting system. The solubilities of D-HPPA increase with increasing mole fraction of ethanol in the methanol-ethanol mixtures. Experimental data were correlated with Buchowski-Ksiazczak λ h equation and modified Apelblat equation; the first one gives better approximation for the experimental results. The enthalpy, entropy and Gibbs free energy of D-HPPA dissolution in methanol, ethanol and methanol-ethanol mixtures were also calculated from the solubility data.

KAJIAN DAERAH RAWAN GELOMBANG TINGGI DI PERAIRAN INDONESIA

Directory of Open Access Journals (Sweden)

Roni Kurniawan

2014-08-01

Full Text Available Berkaitan dengan pentingnya informasi tentang gelombang laut, terutama bagi keselamatan beragam kegiatan di laut, berdasarkan data periode tahun 2000-2010, dilakukan studi tentang gelombang tinggi di perairan Indonesia. Hasil studi menunjukkan bahwa variasi spasial dan temporal tinggi gelombang dan frekuensi terjadinya gelombang tinggi mempunyai pola yang berasosiasi dengan siklus angin monsunal, periode monsun Australia (Desember, Januari, Februari dan monsoon Australia (Juni, Juli, Agustus. Daerah rawan gelombang tinggi pada periode monsun Asia umumnya lebih luas daripada pada periode monsun Australia. Pada periode peralihan antar monsun, sebagian besar wilayah perairan Indonesia tidak rawan gelombang tinggi. Daerah rawan gelombang tinggi pada periode peralihan antar monsun umumnya lebih sempit dan terdapat di perairan Indonesia yang menjadi bagian dari Laut Cina Selatan, Samudera Pasifik dan Samudera Hindia, terutama selatan Jawa sampai Bengkulu. Meskipun korelasinya tidak signifikan, berlangsungnya El- Nino menyebabkan meningkatnya tinggi gelombang di wilayah perairan Indonesia bagian timur, terutama utara ekuator dan berlangsungnya La-Nina menyebabkan meningkatnya tinggi gelombang di perairan Indonesia yang berada di Samudera Hindia terutama di selatan Jawa. Sedangkan terjadinya IODM negatif menyebabkan meningkatnya tinggi gelombang di perairan barat Sumatera sebelah utara ekuator.   Related to the importance of information about ocean waves, especially for the safety of a variety activities at sea, based on data in the period 2000-2010 obtained by numerical wave model, conducted a study of high waves in the Indonesian waters.The study shows that the spatial and temporal variations in wave height and frequency of high waves have a pattern associated with monsunal wind cycle, Australia monsoon period (December, January, February and the Australian monsoon (June, July, August. High waves prone areas in the period of monsoon Asia are

Evaluation of the Analgesic Activity of the Methanolic Stem Bark ...

African Journals Online (AJOL)

Uche

Result: In the acetic acid-induced writhing reflex model, D. guineense extract and the reference drug significantly (P =0.014 .... methanol for 48hrs with intermittent shaking at 2 hrs interval. ... of each of the mice was dipped into a water bath.

A novel condensation reactor for efficient CO2 to methanol conversion for storage of renewable electric energy

NARCIS (Netherlands)

Bos, Martin Johan; Brilman, Derk Willem Frederik

2015-01-01

A novel reactor design for the conversion of CO2 and H2 to methanol is developed. The conversion limitations because of thermodynamic equilibrium are bypassed via in situ condensation of a water/methanol mixture. Two temperatures zones inside the reactor ensure optimal catalyst activity (high

The Effect of Time dealumination and Solvent Concentration in Synthesis of Zeolite Catalyst and Catalytic Test for DiEthyl Ether Production Process

International Nuclear Information System (INIS)

Widayat; Roesyadi, A.; Rachimoellah, M.

2009-01-01

Ethanol is an alternative energy, but its has three distinct disadvantages as a transportation fuel. Its availability is currently limited, and it has a lower volumetric heating value and a lower Reid vapour pressure (RVP) than gasoline. This paper focuses for this disadvantages and to solve this problem can do with converts ethanol to DiEthyl Ether product. This research produced DiEthyl Ether by ethanol dehydration process with zeolite as catalyst. The catalyst synthesis from natural material from District Gunung Kidul, Indonesia. The catalyst produced with dealumination, neutralization, drying and calcination processes. The zeolite catalyst was analysed of Si/Al, X-ray Diffraction and specific surface area. The catalyst product then used for ethanol dehydration to produce DiEthyl Ether. The results shown the biggest surface area is 184,52 m 2 /gram at catalyst production at 10 hours for time dealumination. The crystallite of catalyst product is similar like shown at diffractogram of XRD analysis. The ratio Si/Al biggest is 313.7 that obtaining at catalyst production with 7 hours for time dealumination. The catalytic test use fixed bed reactor with 1 inci diameter and ethanol fermentation both as feed. The operation condition is 150 deg. C at temperature and atmosphere pressure. The compounds product in liquid phase are diethyl ether, methanol and water.

Triboluminescence and associated decomposition of solid methanol

International Nuclear Information System (INIS)

Trout, G.J.; Moore, D.E.; Hawke, J.G.

1975-01-01

The decomposition is initiated by the cooling of solid methanol through the β → α transiRon at 157.8K, producing the gases hydrogen, carbon monoxide, and methane. The passage through this lambda transition causes the breakup of large crystals of β-methanol into crystallites of α-methanol and is accompanied by light emission as well as decomposition. This triboluminescence is accompanied by, and apparently produced by, electrical discharges through methanol vapor in the vicinity of the solid. The potential differences needed to produce the electrical breakdown of the methanol vapor apparently arise from the disruption of the long hydrogen bonded chains of methanol molecules present in crystalline methanol. Charge separation following crystal deformation is a characteristic of substances which exhibit gas discharge triboluminescence; solid methanol has been found to emit such luminescence when mechanically deformed in the absence of the β → α transition The decomposition products are not produced directly by the breaking up of the solid methanol but from the vapor phase methanol by the electrical discharges. That gas phase decomposition does occur was confirmed by observing that the vapors of C 2 H 5 OH, CH 3 OD, and CD 3 OD decompose on being admitted to a vessel containing methanol undergoing the β → α phase transition. (U.S.)

Packing stress reduction in polymer-lipid monolayers at the air-water interface: An X-ray grazing-incidence diffraction and reflectivity study

Energy Technology Data Exchange (ETDEWEB)

Kuhl, T.L.; Majewski, J.; Howes, P.B.; Kjaer, K.; Nahmen, A. von; Lee, K.Y.C.; Ocko, B.; Israelachvili, J.N.; Smith, G.S.

1999-08-25

Using synchrotron grazing-incidence X-ray diffraction (GIXD) and reflectivity (XR), the authors have determined the in-plane and out-of-plane structure of phospholipid monolayers at the air-water interface as a function of hydrophilic lipid headgroup size. Di-stearoyl-phosphatidyl-ethanolamine (DSPE) lipid monolayers were systematically modified by chemically grafting hydrophilic poly(ethylene glycol) (PEG) chains of MW = 90 g/mol (2 ethylene oxide, EO, units), MW = 350 g/mol (8 EO units), and MW = 750 g/mol (17 EO units) to the lipid headgroups. The monolayers were studied in the solid phase at a surface pressure of 42 mN/m. At these high lipid packing densities, the PEG chains are submerged in the water subphase. The increased packing stresses from these bulky polymer headgroups distort the unit cell and the in-plane packing modes of the monolayers, leading to large out-of-plane alterations and staggering of the lipid molecules. Surprisingly, a change in the molecular packing of the monolayer toward higher packing densities (lower area per molecule) was observed on increasing the PEG MW to 750 g/mol (17 EO units). This rearrangement of the monolayer structure may be due to a conformational change in the PEG chains.

Thermodynamics of complexes formation by ITC in methanol/water = 9/1 (v/v) solution: A case study

Energy Technology Data Exchange (ETDEWEB)

Fisicaro, Emilia, E-mail: emilia.fisicaro@unipr.it [University of Parma, Department of Pharmacy, Parco Area delle Scienze, 27/A, 43124 Parma (Italy); Compari, Carlotta; Bacciottini, Franco; Contardi, Laura [University of Parma, Department of Pharmacy, Parco Area delle Scienze, 27/A, 43124 Parma (Italy); Carcelli, Mauro; Rispoli, Gabriele; Rogolino, Dominga [University of Parma, Department of Chemistry, Parco Area delle Scienze, 17/A, 43124 Parma (Italy)

2014-06-01

Graphical abstract: Integrase strand transfert inhibitors chelate the metal ions in the active site of HIV integrase. - Highlights: • Development of inhibitors acting against those viral enzymes operating via a cooperative two-metal ion mechanism, such as HIV integrase (IN), requires optimizing the binding affinity to the target. • We have defined an experimental procedure for obtaining reliable thermodynamic data by ITC in methanol/water = 9/1 (v/v) as solvent. • Formation heats in mixed solvent of the complexes formed by a ligand, model of Raltegravir, with Mg(II), Mn(II), Co(II) and Zn(II) are here reported. - Abstract: Most enzymes that participate in the biochemistry of nucleic acids require divalent metal ion cofactors to promote activity. Development of potent inhibitors, acting against those viral enzymes operating via a cooperative two-metal ion mechanism, such as HIV integrase (IN) and RNase H, hepatitis C virus polymerase and influenza endonuclease, requires optimizing the binding affinity to the target, which is dictated by the binding free energy composed of both enthalpic and entropic contributions. They can be obtained by using isothermal titration microcalorimetry. We have defined an experimental procedure for obtaining reliable thermodynamic data in methanol/water = 9/1 0.1 M KCl as solvent, used to overcome solubility problems. In this way we have measured the heats of formation of the complexes formed by N-(4-fluorobenzyl)-5-hydroxy-2-isopropyl-1-methyl-6-oxo-1, 6-dihydroxypyrimidine-4-carboxylate (HL, a model of Raltegravir, the antiretroviral drug produced by Merck and Co.), and a series of divalent metal ions of biological interest (Mg(II), Mn(II), Co(II) and Zn(II)), whose speciation was previously determined by potentiometry.

Structural insights into methanol-stable variants of lipase T6 from Geobacillus stearothermophilus.

Science.gov (United States)

Dror, Adi; Kanteev, Margarita; Kagan, Irit; Gihaz, Shalev; Shahar, Anat; Fishman, Ayelet

2015-11-01

Enzymatic production of biodiesel by transesterification of triglycerides and alcohol, catalyzed by lipases, offers an environmentally friendly and efficient alternative to the chemically catalyzed process while using low-grade feedstocks. Methanol is utilized frequently as the alcohol in the reaction due to its reactivity and low cost. However, one of the major drawbacks of the enzymatic system is the presence of high methanol concentrations which leads to methanol-induced unfolding and inactivation of the biocatalyst. Therefore, a methanol-stable lipase is of great interest for the biodiesel industry. In this study, protein engineering was applied to substitute charged surface residues with hydrophobic ones to enhance the stability in methanol of a lipase from Geobacillus stearothermophilus T6. We identified a methanol-stable variant, R374W, and combined it with a variant found previously, H86Y/A269T. The triple mutant, H86Y/A269T/R374W, had a half-life value at 70 % methanol of 324 min which reflects an 87-fold enhanced stability compared to the wild type together with elevated thermostability in buffer and in 50 % methanol. This variant also exhibited an improved biodiesel yield from waste chicken oil compared to commercial Lipolase 100L® and Novozyme® CALB. Crystal structures of the wild type and the methanol-stable variants provided insights regarding structure-stability correlations. The most prominent features were the extensive formation of new hydrogen bonds between surface residues directly or mediated by structural water molecules and the stabilization of Zn and Ca binding sites. Mutation sites were also characterized by lower B-factor values calculated from the X-ray structures indicating improved rigidity.

Assessment of cardiotoxic potential of methanol extract of red ...

African Journals Online (AJOL)

The effects of oral administration of crude methanol extract of red cultivar Allium cepa (Onion) on serum cardiac troponin (cTnI) in cardiac muscle and some haematological parameters were investigated in this study. Fifty five (55) male albino rats were housed and fed with standard growers ration and water ad libitum.

Preparation and charaterization of Pt/functionalized graphene and its electrocatalysis for methanol oxidation

International Nuclear Information System (INIS)

Liang, Qingsheng; Zhang, Li; Cai, Maolin; Li, Yong; Jiang, Kun; Zhang, Xin; Shen, Pei Kang

2013-01-01

Water-dispersible 8-hydroxy-1,3,6-pyrene trisulfonic acid trisodium salt (PyS)-functionalized graphene (PyS-graphene) sheets were prepared by a π–π interaction method, in which the aromatic organic molecules of PyS were reacted with graphene. The PyS-graphene sheets were used as Pt nanoparticle support to prepare a Pt/PyS-graphene catalyst for direct methanol fuel cells. The prepared materials were characterized by ultraviolet spectrometry (UV–vis), Fourier transform infrared spectrometry (FT-IR), atomic force microscopy (AFM), X-ray diffraction (XRD), Raman spectroscopy (SERS), and transmission electron microscopy (TEM). The electrocatalytic properties of the catalysts for methanol oxidation were evaluated by cyclic voltammetry (CV). The Pt/PyS-graphene catalysts were found to have higher electrocatalytic activity for methanol oxidation than Pt/graphene catalyst. This finding can be attributed to the introduction of negative sulfonic (SO 3 − ) groups to the graphene sheet surface, which makes the graphene sheets dispersible in water. Consequently, the Pt nanoparticles were uniformly and securely deposited onto the graphene sheet surface. These results suggested that the sulfonic group-modified water-dispersible graphene sheets can be used to improve the electrocatalytic activity of catalysts for fuel cells

STUDI KONEKTIVITAS AKUIFER ANTARA SUMUR BOR DENGAN SUMBER DAYA AIR DI BAWAHNYA (Study on Aquifer Connectivity, between Boreholes with water resources underneath

Directory of Open Access Journals (Sweden)

Agus Budhie Wijatna

2013-11-01

Full Text Available ABSTRAK Untuk memenuhi kebutuhan air bersih bagi penduduk di daerah bekas bencana letusan Gunung Merapi, Kabupaten Sleman, DIY, telah dibuat 5 sumur bor di Dusun Srunen (BH1, Pagerjurang (BH2, Ngepring (BH3, Kuweron (BH4, dan di Dusun Bubur (BH5. Pembuatan sumur bor pada elevasi antara 544 sampai 846 m.dpl, dengan kedalaman antara 98-146 m dan debit pengambilan airtanah rerata 9-10 liter per detik tersebut dikawatirkan akan mempengaruhi kondisi muka airtanah sumur gali di Dusun Pendowoharjo (W7, Ngaglik (W8, Gebang (W9, Condong Catur (W10, sumur UGM (W11 dan mempengaruhi debit umbul (mataair Ngepas (S8, Umbul Jogopaten (S9, Umbul Pajangan (S10, Umbul Londo (S11, Umbul Permai (S12, dan Umbul Seturan (S13, yang berada pada elevasi 148-329 m.dpl. Secara teoritis, pengambilan airtanah di sumur bor akan berpengaruh jika terdapat interkoneksi hidraulik antara sumur bor dengan sumur gali dan mataair. Pada penelitian ini, interkoneksi hidraulik antara sumur bor dengan sumur gali dan mataair dilakukan menggunakan isotop lingkungan (D, 3H dan 18O. Penelitian diawali dengan menentukan lokasi pengambilan sampel airtanah berdasarkan peta topografi dan kondisi hidrologi; sampel airtanah diambil dari sumur bor, sumur gali dan mataair sebanyak 30 ml dan 1.000 ml; rasio isotop δD dan δ18O pada sampel airtanah diukur dengan liquid-water stable isotope analyzer LGR DLT-100, sedangkan kadar tritium diukur dengan Liquid Scientillation Counter (LSC Tri Carb 1900 TR. Genesis sampel airtanah ditentukan berdasarkan komposisi isotop (δ18O, δD dengan mengacu pada persamaan Merapi Meteoric Water Line (MMWL; sedangkan untuk memastikan adanya interkoneksi hidraulik, maka hasil pengukuran kadar tritium dianalisis dengan tritium dating method. Hasil penelitian menunjukkan bahwa genesis airtanah di BH1, BH2, BH3, dan BH4 berbeda dengan genesis airtanah sumur gali dan mataair di bawahnya. Sehingga dapat disimpulkan airtanah sumur bor di BH1, BH2, BH3, dan BH4 tidak memiliki

Structure elucidation and toxicity analyses of the radiolytic products of aflatoxin B{sub 1} in methanol-water solution

Energy Technology Data Exchange (ETDEWEB)

Wang, Feng [Institute of Agro-food Science and Technology of Chinese Academy of Agricultural Sciences, 2nd Yuanmingyuan West Road, Hai Dian District, Beijing 100193 (China); Key Opening Laboratory of Agricultural Products Processing and Quality Control, Ministry of Agriculture, 2nd Yuanmingyuan West Road, Hai Dian District, Beijing 100193 (China); Graduate School of Chinese Academy of Agricultural Sciences, 12th Zhongguancun South Road, Hai Dian District, Beijing 100081 (China); Xie, Fang [Institute of Agro-food Science and Technology of Chinese Academy of Agricultural Sciences, 2nd Yuanmingyuan West Road, Hai Dian District, Beijing 100193 (China); Key Opening Laboratory of Agricultural Products Processing and Quality Control, Ministry of Agriculture, 2nd Yuanmingyuan West Road, Hai Dian District, Beijing 100193 (China); Xue, Xiaofeng [Bee Research Institute of Chinese Academy of Agricultural Sciences, 1st Xiangshan North Ditch, Hai Dian District, Beijing 100093 (China); Wang, Zhidong; Fan, Bei [Institute of Agro-food Science and Technology of Chinese Academy of Agricultural Sciences, 2nd Yuanmingyuan West Road, Hai Dian District, Beijing 100193 (China); Key Opening Laboratory of Agricultural Products Processing and Quality Control, Ministry of Agriculture, 2nd Yuanmingyuan West Road, Hai Dian District, Beijing 100193 (China); Ha, Yiming, E-mail: wxfay2011@hotmail.com [Institute of Agro-food Science and Technology of Chinese Academy of Agricultural Sciences, 2nd Yuanmingyuan West Road, Hai Dian District, Beijing 100193 (China); Key Opening Laboratory of Agricultural Products Processing and Quality Control, Ministry of Agriculture, 2nd Yuanmingyuan West Road, Hai Dian District, Beijing 100193 (China)

2011-09-15

Highlights: {yields} Radiolytic products of aflatoxin B{sub 1} were produced under gamma irradiation. {yields} Seven key radiolytic products were structure-elucidated. {yields} Free-radical species in radiolytic solution resulted in the formation of products. {yields} Based on the structure-activity relationship analysis, the toxicity of radiolytic products was significantly reduced compared with that of AFB{sub 1}. {yields} The addition reaction on furan ring double bond was the reason for the reduced toxicity. - Abstract: The identification of the radiolytic products of mycotoxins is a key issue in the feasibility study of gamma ray radiation detoxification. Methanol-water solution (60:40, v/v) spiked with aflatoxin B{sub 1} (AFB{sub 1}; 20 mg L{sup -1}) was irradiated with Co{sup 60} gamma ray to generate radiolytic products. Liquid chromatography-quadruple time-of-flight mass spectrometry was applied to identify the radiolytic products of AFB{sub 1}. Accurate mass and proposed molecular formulas with a high-matching property of more than 20 radiolytic products were obtained. Seven key radiolytic products were proposed based on the molecular formulas and tandem mass spectrometry spectra. The analyses of toxicity and formation pathways were proposed based on the structure of the radiolytic products. The addition reaction caused by the free-radical species in the methanol-water solution resulted in the formation of most radiolytic products. Based on the structure-activity relationship analysis, the toxicity of radiolytic products was significantly reduced compared with that of AFB{sub 1} because of the addition reaction that occurred on the double bond in the terminal furan ring. For this reason, gamma irradiation is deemed an effective tool for the detoxification of AFB{sub 1}.

Photoelectrochemical hydrogen production from water/methanol decomposition using Ag/TiO{sub 2} nanocomposite thin films

Energy Technology Data Exchange (ETDEWEB)

Alenzi, Naser; Ehlig-Economides, Christine [Harold Vance Department of Petroleum Engineering, Texas A and M University, College Station, TX 77843 (United States); Liao, Wei-Ssu; Cremer, Paul S. [Department of Chemistry, Texas A and M University, College Station, TX 77843 (United States); Sanchez-Torres, Viviana; Cheng, Zhengdong [Artie McFerrin Department of Chemical Engineering, Texas A and M University, College Station, TX 77843 (United States); Wood, Thomas K. [Artie McFerrin Department of Chemical Engineering, Texas A and M University, College Station, TX 77843 (United States); Department of Biology, Texas A and M University, College Station, TX 77843-3258 (United States); Zachry Department of Civil and Environmental Engineering, Texas A and M University, College Station, TX 77843 3136 (United States)

2010-11-15

Though less frequently studied for solar-hydrogen production, films are more convenient to use than powders and can be easily recycled. Anatase TiO{sub 2} films decorated with Ag nanoparticles are synthesized by a rapid, simple, and inexpensive method. They are used to cleave water to produce H{sub 2} under UV light in the presence of methanol as a hole scavenger. A simple and sensitive method is established here to monitor the time course of hydrogen production for ultralow amounts of TiO{sub 2}. The average hydrogen production rate of Ag/TiO{sub 2} anatase films is 147.9 {+-} 35.5 {mu}mol/h/g. Without silver, it decreases dramatically to 4.65 {+-} 0.39 {mu}mol/h/g for anatase TiO{sub 2} films and to 0.46 {+-} 0.66 {mu}mol/h/g for amorphous TiO{sub 2} films fabricated at room temperature. Our method can be used as a high through-put screening process in search of high efficiency heterogeneous photocatalysts for solar-hydrogen production from water-splitting. (author)

Optimization of the synthesis of SAPO-11 for the methylation of naphthalene with methanol by varying templates and template content

International Nuclear Information System (INIS)

Wang, Xiaoxiao; Zhang, Wei; Zhao, Liangfu; Xiang, Hongwei; Guo, Shaoqing

2013-01-01

SAPO-11 zeolites were successfully synthesized by using three different templates (diethylamine (DEA), di-n-propylamine (DPA) and di-isopropylamine (DIPA)) and varying DPA contents (nDPA/Al 2 O 3 = 0.8, 1.2, 1.6 and 2.0) under hydrothermal conditions. The samples were characterized by powder X-ray diffractometry (XRD), scanning electron microscopy (SEM), N 2 adsorption-desorption, temperature programmed desorption of ammonia (NH 3 -TPD) and 29 Si magic angle spinning (MAS) nuclear magnetic resonance (NMR). The samples were also evaluated towards the methylation of naphthalene with methanol to produce 2,6-dimethylnaphthalene (2,6-DMN). XRD results indicated that the directing effect of the different templates for AEL (Aluminophosphate-ELeven) structure decreased in the order DPA > DEA > DIPA and the most suitable DPA content was nDPA/Al 2 O 3 = 1.2. N 2 adsorption-desorption results showed that SAPO-11(DPA,1.2) exhibited the broadest pore size distribution, the highest BET specific surface area and the largest pore volume among all the SAPO-11 samples. SAPO-11(DPA,1.2) exhibited high catalytic performances in the methylation of naphthalene due to its high crystallinity, high external surface and broad pore size distribution. The pore structure of SAPO-11 zeolite, rather than its acidity, played an important role in achieving high catalytic performances in the methylation of naphthalene with methanol. (author)

Il crowdfunding finalizzato al co-finanziamento di progetti di valorizzazione di complessi di elevato valore storico architettonico: il caso di “Torino Esposizioni”

Directory of Open Access Journals (Sweden)

Paola Marinò

2015-12-01

Full Text Available L’articolo affronta il tema del finanziamento degli interventi di restauro e riuso delle grandi architetture del ‘900, in un momento storico in cui le risorse finanziarie pubbliche sono sempre più scarse e difficili da reperire. La ricerca affronta la possibilità di ricorrere al crowdfunding attraverso il caso studio del progetto di “Torino Esposizioni”, un’architettura del ‘900, parzialmente utilizzata, in stato di degrado, nonostante sia riconosciuta dalla critica internazionale come un’opera di eccezionale valore. A partire dal Master Plan, messo a punto dal Politecnico di Torino in collaborazione con la Città di Torino, è stata simulata l’applicabilità del crowdfunding attraverso un’indagine che valuta la disponibilità a contribuire da parte dei potenziali fruitori del complesso di “Torino Esposizioni” e, quindi, a comprendere l’interesse dei cittadini nei confronti del valore storico del complesso di “Torino Esposizioni” e del progetto di riuso che dovrebbe valorizzarlo. Gli esiti della ricerca, nell’evidenziare un’inattesa scarsa disponibilità a contribuire al finanziamento collettivo del progetto, hanno messo in evidenza, non solo la scarsa conoscenza del crowdfunding come strumento di finanziamento, ma anche la scarsa consapevolezza del valore storico architettonico del patrimonio moderno della città di Torino, di cui “Torino Esposizioni” rappresenta un esempio eccezionale, seppur non l’unico.

Definition of dose intensity (DI), average relative DI and effective DI

International Nuclear Information System (INIS)

Alberto, P.

1995-01-01

The cytotoxic activity of cancer chemotherapy is related to the dose and to the amount of drug delivered per time unit. the significance of time in the effectiveness of a treatment program is frequently overlooked. The term of dose intensity (DI) is used to define the drug dose delivered per time unit and is expressed as mg/m 2 per week. A delay in the sequence of treatment cycles decreases the DI in the DI in the same proportion as a reduction of dose. Average relative DI corresponds to the mean DI of combined agents and is expressed as a fraction of a similar combination selected as a standard. Di is useful to compare the dose actually received with the prescribed dose. The relation of DI with tumor response or survival has not been fully demonstrated. A threshold DI level for therapeutic activity is evident. Above this threshold, a linear relationship of DI and effectiveness is not obvious, particularly regarding high-dose chemotherapy. The term of DI is more useful in its principle than in the significance of its calculated value. (authors). 19 refs., 3 tabs., 3 figs

Reti di città, mobilità e ambiente: il Preliminare di PTCP di Avellino

Directory of Open Access Journals (Sweden)

Carmela Gargiulo

2010-02-01

Full Text Available  L’articolo propone la lettura dei contenuti del Preliminare del PTCP di Avellino, un piano per molti aspetti innovativo, soprattutto per aver coniugato pianificazione di area vasta di tipo tradizionale e logica “strategica”. In particolare, l’articolo descrive idee guida, contenuti e strategie del piano orientate, prevalentemente, a stimolare lo sviluppo sostenibile di un’area in ritardo di sviluppo come la provincia irpina, attraverso la salvaguardia e valorizzazione delle risorse naturali e storico-culturali, la costruzione di reti di medie e piccole città e reti di mobilità alle diverse scale, da quella urbana a quella internazionale, e interventi sul sistema della mobilità. Nel 2004, ormai più di cinque anni fa, è stato adottato, a maggioranza assoluta (solo due gli astenuti, il Preliminare di Piano Territoriale di Coordinamento della Provincia di Avellino, dopo un lavoro di oltre due anni che ha visto impegnati gli uffici provinciali con due dipartimenti universitari. Il lavoro, che va ben oltre il significato e la valenza di un preliminare e che coniuga due pratiche di piano diverse (quella tradizionale e quella strategica ruota attorno a tre idee di fondo, tra loro strettamente interrelate, che costituiscono i criteri guida che finora ha inteso seguire la provincia di Avellino nell’attività di governo delle trasformazioni. Tali idee, quindi, costituiscono le fondamenta su cui è stato costruito il Preliminare e sono la griglia di specificazione delle strategie e degli obiettivi di piano. Esse sono alla base delle scelte elaborate per lo sviluppo compatibile del territorio, e sono riferibili alle azioni operative di trasformazione del territorio che gli Enti locali, cui è demandato tale compito, nel prossimo futuro dovranno affrontare. Le tre idee forza del Preliminare, descritte nel seguito, sono riferibili ai sistemi di risorse principali della provincia di Avellino, oggetto di una indagine analitico

Biodiesel production via injection of superheated methanol technology at atmospheric pressure

International Nuclear Information System (INIS)

Ang, Gaik Tin; Tan, Kok Tat; Lee, Keat Teong; Mohamed, Abdul Rahman

2014-01-01

Highlights: • Non-catalytic superheated methanol for biodiesel production is developed. • Crude Jatropha curcas oil with high FFA can be directly used as oil feedstock. • High content of biodiesel can be produced. • Separation of FAME and glycerol from the sample product is easy. - Abstract: In this high demand of renewable energy market, biodiesel was extensively produced via various catalytic and non-catalytic technologies. Conventional catalytic transesterification for biodiesel production has been shown to have limitation in terms of sensitivity to high water and free fatty acid, complicated separation and purification of biodiesel. In this study, an alternative and innovative approach was carried out via non-catalytic superheated methanol technology to produce biodiesel. Similar to supercritical reaction, the solvent need to be heated beyond the critical temperature but the reactor pressure remained at 0.1 MPa (atmospheric pressure). Transesterification reaction with superheated methanol was carried out at different reaction temperature within the limit of 270–300 °C and at different methanol flow rate ranging from 1 ml/min to 3 ml/min for 4 h. Results obtained showed that the highest biodiesel yield at 71.54% w/w was achieved at reaction temperature 290 °C and methanol flow rate at 2 ml/min with 88.81% w/w FAME content, implying the huge potential of superheated technology in producing FAME

KEBUN RAYA BOTANI DENGAN SISTEM WTP (WATER TREATMENT PLAN DI MAKASSAR

Directory of Open Access Journals (Sweden)

Sri Innayah Wahid

2015-12-01

Full Text Available Abstrak—Pariwisata merupakan salah satu sumber devisa yang sangat potensial dan mempunyai andil besar dalam membangun perekonomian yang memiliki nilai jual menjadi objek yang menguntungkan bagi kemajuan Makassar. Tujuan wisata yang hanya ada di Makassar menciptakan rasa ingin tahu pengunjung untuk berkunjung.Pengunjung yang datang menginvestasikan akomodasi seluruh kegiatan wisata dengan pengusaha lokal setempat.Pengunjung domestik maupun asing juga menjadi sumber pendapatan bagi masyarakat yang tinggal di sekitar objek wisata. Laporan ini bertujuan untuk menata elemen-elemen fisik kawasan seperti tata guna lahan, bentuk dan massa bangunan, jalur pejalan kaki, sirkulasi dan parker signage atau penanda, serta fasilitas pendukung kedalam suatu kawasan kebun raya botani yang dibutuhkan untuk mencapai kenyamanan bagi para pengguna lahan dan menerapkan sistem WTP dalam bentuk desain yang bersifat berkelanjutan (sustainable.dan tujuan non arsitektural yang lain untuk merumuskan kegiatan rekayasa tumbuhan secara alami sehingga kebun raya botani dapat menjadi alternatif pusat pendidikan, mengelompokkan tanaman yang sesuai dengan iklim dan kondisi tapak kebun raya botani, untuk menentukan sistem kerja WTP dalam kebun raya botani yang dapat memenuhi kebutuhan tanaman. Hasil laporan ini berupa desain penataan kebun raya botani dengan sistem WTP (water Treatment Plan di Makassar Kata Kunci :kebun raya botani, WTP Abstract- Tourism is one potential source of foreign exchange and have a larger share in building an economy that has a sale value into an object that is beneficial to the progress of Makassar. Tourist destinations that exist only in Makassar creates curiosity of visitors to visit. Visitors who come to invest accommodation all over the local tourism activities with local entrepreneurs. Domestic and foreign visitors are also a source of income for the people who live around the attraction. This report aims to restructure the physical elements

Two-phase, mass-transport model for direct methanol fuel cells with effect of non-equilibrium evaporation and condensation

Science.gov (United States)

Yang, W. W.; Zhao, T. S.

A two-phase, mass-transport model for liquid-feed direct methanol fuel cells (DMFCs) is developed by taking into account the effect of non-equilibrium evaporation and condensation of methanol and water. The comparison between the present model and other models indicates that the present model yields more reasonable predictions of cell performance. Particularly, it is shown that the models that invoke a thermodynamic-equilibrium assumption between phases will overestimate mass-transport rates of methanol and water, thereby resulting in an inaccurate prediction of cell performance. The parametric study using the present model reveals that the gas coverage at the flow channel-diffusion-layer interface is directly related to the gas-void fraction inside the anode porous region; increasing the gas-void fraction will increase the mass-transfer resistance of methanol and thus lower cell performance. The effects of the geometric dimensions of the cell structure, such as channel width and rib width, on cell performance are also investigated with the model developed in this work.

Effect of pervaporation plate thickness on the rate of methanol evaporation in a passive vapor-feed direct methanol fuel cell

Science.gov (United States)

Fauzi, N. F. I.; Hasran, U. A.; Kamarudin, S. K.

2015-09-01

In a passive vapor-feed direct methanol fuel cell (DMFC), methanol vapor is typically obtained using a pervaporation plate in a process by which liquid methanol contained in the fuel reservoir undergoes a phase change to vapor in the anodic vapor chamber. This work investigates the effect of pervaporation plate thickness on the rate of methanol evaporation using a three-dimensional simulation model developed by varying the plate thickness. A. The rate of methanol evaporation was measured using Darcy's law. The rate of methanol evaporation was found to be inversely proportional to the plate thickness, where the decrease in thickness inevitably lowers the resistance along the plate and consequently increases the methanol transport through the plate. This shows that the plate thickness has a significant influence on the rate of methanol evaporation and thereby plays an important role in improving the performance of the passive vapor-feed direct methanol fuel cell.

Methanol Reforming over Cobalt Catalysts Prepared from Fumarate Precursors: TPD Investigation

Directory of Open Access Journals (Sweden)

Eftichia Papadopoulou

2016-02-01

Full Text Available Temperature-programmed desorption (TPD was employed to investigate adsorption characteristics of CH3OH, H2O, H2, CO2 and CO on cobalt-manganese oxide catalysts prepared through mixed Co-Mn fumarate precursors either by pyrolysis or oxidation and oxidation/reduction pretreatment. Pyrolysis temperature and Co/Mn ratio were the variable synthesis parameters. Adsorption of methanol, water and CO2 was carried out at room temperature. Adsorption of H2 and H2O was carried out at 25 and 300 °C. Adsorption of CO was carried out at 25 and 150 °C. The goal of the work was to gain insight on the observed differences in the performance of the aforementioned catalysts in methanol steam reforming. TPD results indicated that activity differences are mostly related to variation in the number density of active sites, which are able to adsorb and decompose methanol.

Effect of microwave double absorption on hydrogen generation from methanol steam reforming

Energy Technology Data Exchange (ETDEWEB)

Chen, Wei-Hsin; Lin, Bo-Jhih [Department of Greenergy, National University of Tainan, Tainan 700 (China)

2010-03-15

Hydrogen generation from steam reforming of methanol (SRM) with a CuO/ZnO/Al{sub 2}O{sub 3} catalyst was investigated in the study; particular emphasis was placed on the reactions of SRM exposed to an environment with microwave irradiation. By virtue of the double absorption of microwaves by both the reagents and the catalyst, the experiments suggested that the SRM could be heated and triggered rapidly within a short time, and the methanol conversion from SRM with microwave heating was high compared to that with conventional heating. The obtained results also indicated that, when the reaction temperature was as high as 250 C, thermodynamic equilibrium governed the SRM, whereas the reaction was kinetically controlled for the temperature lower than 250 C. Contrary to Le Chatelier's principle, it was noted that an increase in S/C ratio decreased methanol conversion. This can be explained by the fact that water absorbs microwave irradiation stronger than methanol. The performance of the SRM was evaluated based on the carbon conservation method and the nitrogen tracer method. It was found that the latter was also capable of providing an accurate prediction on methanol conversion, even though the flow rate of the product gas was not measured. (author)

Microbial Community Changes in Response to Ethanol or Methanol Amendments for U(VI) Reduction

International Nuclear Information System (INIS)

Vishnivetskaya, Tatiana A.; Brandt, Craig C.; Madden, Andrew; Drake, Meghan M.; Kostka, Joel; Akob, Denise M.; Kusel, Kirsten; Palumbo, Anthony Vito

2010-01-01

Microbial community responses to ethanol, methanol and methanol + humics amendments in relationship to uranium bioremediation were studied in laboratory microcosm experiments using sediments and ground water from a uranium-contaminated site in Oak Ridge, Tennessee. Ethanol addition always resulted in uranium reduction at rate of 0.8-1.0 mol l -1 d -1 while methanol addition did so occasionally at rate 0.95 mol l -1 d -1 . The type of carbon source added, the duration of incubation, and the sampling site influenced the bacterial community structure upon incubation. Analysis of 16S rRNA gene clone libraries indicated (1) bacterial communities found in ethanol- and methanol-amended samples with U(VI) reduction were similar due to presence of -Proteobacteria, and -Proteobacteria (members of the families Burkholderiaceae, Comamonadaceae, Oxalobacteraceae, and Rhodocyclaceae); (2) methanol-amended samples without U(VI) reduction exhibited the lowest diversity and the bacterial community contained 69.2-92.8% of the family Methylophilaceae; and (3) the addition of humics resulted in an increase of phylogenetic diversity of -Proteobacteria (Rodoferax, Polaromonas, Janthinobacterium, Methylophilales, unclassified) and Firmicutes (Desulfosporosinus, Clostridium).

Le collezioni di Mammiferi del Museo Civico di Zoologia di Roma: una sintesi storica

Directory of Open Access Journals (Sweden)

Gloria Svampa

2003-10-01

Full Text Available Il Museo Civico di Zoologia di Roma è sorto nel 1932 all?interno del Giardino Zoologico dell?allora Governatorato di Roma, di cui ha condiviso la direzione tecnica ed amministrativa sino al 1998. Il nucleo centrale delle collezioni è costituito dal materiale di proprietà universitaria, di quello che fu il Museo di Zoologia della Regia Università, a sua volta diretto discendente delle collezioni del Museo di Zoologia ed Anatomia Comparata del Pontificio Archiginnasio Romano. La quasi totalità degli esemplari tassidermizzati risale al periodo in cui l?Istituto di Zoologia fu diretto da Antonio Carruccio (1883-1914. Dal 1932, la collezione teriologica si è andata arricchendo, in particolare di materiale osteologico, soprattutto con acquisizioni provenienti dal Giardino Zoologico e da rare spedizioni scientifiche, come quella organizzata dal CNR nell?Alto Rio Negro del 1962-3, guidata da Ettore Biocca. Anche a causa del fatto che per molti anni il Museo è stato privo di curatori, mancano importanti collezioni teriologiche da studio, fatta eccezione per quella cetologica. In molti casi, singoli esemplari potenzialmente di grande valore scientifico, mancano di dati esatti sulla località di cattura. Nell?ambito di un programma di ricatalogazione della collezione recentemente intrapreso, particolare attenzione è stata posta all?acquisizione di tutti i dati legati alla storia dei singoli esemplari, rintracciabili attraverso i resoconti di viaggio dei singoli esploratori. Nel periodo universitario, infatti, il Museo della nuova capitale d?Italia fu oggetto di grande attenzione da parte di privati ed enti, a partire dai Savoia, che donarono le loro collezioni o il materiale raccolto durante le spedizioni effettuate. Il lavoro di revisione in corso sta mettendo in luce una serie di esemplari meritevoli di ulteriori, dettagliate ricerche. È probabile che molto del materiale del Museo, pervenuto a Roma attraverso donazioni della famiglia reale

Update on status of direct methanol fuel cells

Energy Technology Data Exchange (ETDEWEB)

Reeve, R.W.

2002-07-01

This report reviews the progress in direct methanol fuel cell (DMFC) technology since 1995 and examines the opportunities for this technology in various market sectors. The report is divided into two parts. Part A describes the state-of-the-art of DMFC technology, developments in electrocatalysis relevant to DMFCs, single cell and stack performance, and polymer electrolyte membranes. Part B discusses the viability of current DMFCs for portable and automotive applications, and examines some niche markets, eg for remote power applications. Market opportunities, technical issues, applications and competing technologies are summarised. The report draws attention to the outstanding technical issues and recommends further development in a number of areas (eg inexpensive membranes with lower rates of methanol crossover, membranes with lower rates of water permeation, improved power density and methods to ensure solutions do not freeze in cold climates).

Chromatographic separation of rhenium in alumina-methanol/sulfuric acid system

International Nuclear Information System (INIS)

Oguma, Koichi

1983-01-01

The adsorption behavior of a number of metals on alumina was surveyed in a methanol-(0.005 -- 0.5) M H 2 SO 4 (3 : 1 v/v) developing solvent by thin-layer chromatography. Over the acid concentration range tested, Re(VII) does not favor the alumina phase to any great extent while the most other metals are strongly adsorbed on alumina. These findings allowed to establish a column chromatographic technique for selective separation of rhenium in a methanol-0.05 M H 2 SO 4 (3 : 1 v/v) eluent. The separation technique thus established was applied to molybdenite analysis for rhenium. About 100-mg powdered sample containing ca. 100 ppm rhenium was decomposed with HNO 3 and then evaporated nearly to dryness. The residue was dissolved in NH 4 OH and the excess NH 4 OH was expelled by evaporation to dryness. The residue was dissolved in 2.5-ml 0.5 M H 2 SO 4 and 10-ml water, the insoluble materials filtered off, and the filtrate diluted to exactly 25 ml with water. A 10-ml aliquot of this solution was mixed with 30-ml methanol and the mixture was passed through a column (diameter 15 mm, bed height 30 mm) containing 5 g of alumina. The column was then washed with 20 ml of a methanol-0.05 M H 2 SO 4 (3 : 1 v/v) mixture. Rhenium was recovered from the loaded solution and the subsequent washings, and was determined spectrophotometrically with Methylene Blue as a chromogenic reagent. The values obtained from four samples of molybdenite are in good agreement with those obtained by neutron activation analysis. The relative standard deviation (n = 4; calculated from the range) was between 2.0 and 5.2 %. (author)

Effects of Methanolic Extracts from the Leaves of Brimstone, Cassia ...

African Journals Online (AJOL)

Effects of Methanolic Extracts from the Leaves of Brimstone, Cassia, Lemon Grass and Chanca Piedra on Meloidogyne Incognita in the Laboratory. ... and the highest level (20%) of aqueous extracts of all test plants completely inhibited egg hatch while the control (distilled water only) recorded 93% commulative egg hatch.

Effect of pervaporation plate thickness on the rate of methanol evaporation in a passive vapor-feed direct methanol fuel cell

International Nuclear Information System (INIS)

Fauzi, N F I; Hasran, U A; Kamarudin, S K

2015-01-01

In a passive vapor-feed direct methanol fuel cell (DMFC), methanol vapor is typically obtained using a pervaporation plate in a process by which liquid methanol contained in the fuel reservoir undergoes a phase change to vapor in the anodic vapor chamber. This work investigates the effect of pervaporation plate thickness on the rate of methanol evaporation using a three-dimensional simulation model developed by varying the plate thickness. A. The rate of methanol evaporation was measured using Darcy's law. The rate of methanol evaporation was found to be inversely proportional to the plate thickness, where the decrease in thickness inevitably lowers the resistance along the plate and consequently increases the methanol transport through the plate. This shows that the plate thickness has a significant influence on the rate of methanol evaporation and thereby plays an important role in improving the performance of the passive vapor-feed direct methanol fuel cell. (paper)

Antifungal activity of methanolic root extract of Withania somnifera

African Journals Online (AJOL)

Proff.Adewunmi

remedy for many diseases in various regions of the world, especially in ... For control, 2 mL of DMSO was added to 16 mL of water, and 4 mL of this .... 3E). Since the four organic solvents used for fractionation of methanolic root .... Purification of a Lectin-Like Antifungal Protein from the Medicinal Herb, Withania Somnifera.

Methanol Reformer System Modeling and Control using an Adaptive Neuro-Fuzzy Inference System approach

DEFF Research Database (Denmark)

Justesen, Kristian Kjær; Ehmsen, Mikkel Præstholm; Andersen, John

2012-01-01

This work presents the experimental study and modelling of a methanol reformer system for a high temperature polymer electrolyte membrane (HTPEM) fuel cell stack. The analyzed system is a fully integrated HTPEM fuel cell system with a DC/DC control output able to be used as e.g. a mobile battery...... charger. The advantages of using a HTPEM methanol reformer is that the high quality waste heat can be used as a system heat input to heat and evaporate the input methanol/water mixture which afterwards is catalytically converted into a hydrogen rich gas usable in the high CO tolerant HTPEM fuel cells....... Creating a fuel cell system able to use a well known and easily distributable liquid fuel such as methanol is a good choice in some applications such as range extenders for electric vehicles as an alternative to compressed hydrogen. This work presents a control strategy called Current Correction...

Synergistic Effect of Molybdate and Monoethanolamine on Corrosion Inhibition of Ductile Cast Iron in Tap Water

Energy Technology Data Exchange (ETDEWEB)

Kim, K. T.; Kim, Y. S. [Andong National University, Andong (Korea, Republic of); Chang, H. Y.; Lim, B. T.; Park, H. B. [KEPCO Engineering and Construction Company, Gimcheon (Korea, Republic of)

2017-02-15

A synergistic effect was observed in the combination of nitrite and ethanolamines. Ethanolamine is one of the representative organic corrosion inhibitors and can be categorized as adsorption type. However, nitrosamines can form when amines mix with sodium nitrite. Since nitrosamine is a carcinogen, the co-addition of nitrite and ethanolamine will be not practical, and thus, a non-toxic combination of inhibitors shall be needed. In order to maximize the effect of monoethanolamine, we focused on the addition of molybdate. Molybdate has been used to alternate the addition of chromate, but it showed insufficient oxidizing power relative to corrosion inhibitors. This work evaluated the synergistic effect of the co-addition of molybdate and monoethanolamine, and its corrosion mechanism was elucidated. A high concentration of molybdate or monoethanolamine was needed to inhibit the corrosion of ductile cast iron in tap water, but in the case of the co-addition of molybdate and monoethanolamine, a synergistic effect was observed. This synergistic effect could be attributed to the molybdate that partly oxidizes the metallic surface and the monoethanolamine that is simultaneously adsorbed on the graphite surface. This adsorbed layer then acts as the barrier layer that mitigates galvanic corrosion between the graphite and the matrix.

Methanol May Function as a Cross-Kingdom Signal

Science.gov (United States)

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

STATUS INTRODUKSI IKAN DAN STRATEGI PELAKSANAAN SECARA BERKELANJUTAN DI PERAIRAN UMUM DARATAN DI INDONESIA

Directory of Open Access Journals (Sweden)

Chairulwan Umar

2013-11-01

Full Text Available Masuknya jenis ikan asing berpotensi merubah keseimbangan pada perairan umum daratan, dan di Indonesia gejala ini sudah mulai terlihat. Makalah ini bertujuan untuk membahas lebih lanjut tentang perkembangan introduksi ikan asing, strategi pelaksanaan intoduksi dan berbagai dampaknya terhadap komunitas ikan asli perairan di Indonesia. Penelitian dilakukan melalui penelusuran dan studi pustaka tentang: sejarah kegiatan introduksi ikan yang dilakukan ke Indonesia, jenis-ikan introduksi ikan di Indonesia dan kegiatan introduksi ikan yang telah dan dilakukan di Indonesia beserta dampaknya. Verifikasi lapangan dilakukan pada tahun 2011 di beberapa danau dan waduk antara lain Danau Sentani, Danau Kerinci, Danau Matano dan Waduk Riam Kanan. Data yang terkumpul ditabulasi dan dianalisis secara deskriptif. Hasil penelitian menunjukkan bahwa introduksi ikan asing dilakukan di Indonesia sebelum tahun 1900. Introduksi ikan yang telah dilakukan selama ini, lebih banyak dilakukan tanpa melalui kajian ilmiah yang mendalam dan telah terbukti mengakibatkan hilang atau berkurangnya populasi ikan asli atau endemik serta menjadi agen pembawa penyakit. The entry of alien fish species could potentially change the balance of the inland waters and in Indonesia this symptoms was shown. The paper aims are to discuss more about the development introduction of alien fish species, the introduction implementation strategy and its impact to indigenous fish species communities in Indonesian inland waters. The study was conducted through a literature research about: the history of fish introductions activities which carried out in Indonesia, the species of fish introduction in Indonesia and the activities of introduction fish that have been conducted in Indonesia and its impact. Field verification was conducted in 2011 at several lakes and reservoir such us: Sentani Lake, Kerinci Lake, Matano Lake and Riam Kanan Reservoir. The collected data were tabulated and analyzed

Ethanol from lignocellulosic biomasses; Etanolo da biomasse lignocellulosiche. Produzione di etanolo da paglia di grano mediante pretrattamento di steam explosion, idrolisi enzimatica e fermentazione

Energy Technology Data Exchange (ETDEWEB)

Ricci, E.; Viola, E.; Zimbardi, F.; Braccio, G. [ENEA, Divisione Fonti Rinnovabili di Energia, Centro Ricerche Trisaia, Policoro, Matera (Italy); Cuna, D. [Faucitano Srl, Milan (Italy)

2001-07-01

In this report are presented results achieved on the process optimisation of bioethanol production from wheat straw, carried out within the ENEA's project of biomass exploitation for renewable energy. The process consists of three main steps: 1) biomass pretreatment by means of steam explosion; 2) enzymatic hydrolysis of the cellulose fraction; 3) fermentation of glucose. To perform the hydrolysis step, two commercial enzymatic mixtures have been employed, mainly composed by {beta}-glucosidase (cellobiase), endo-glucanase and exo-glucanase. The ethanologenic yeast Saccharomyces cerevisiae has been used to ferment the glucose in he hydrolyzates. Hydrolysis yield of 97% has been obtained with steam exploded wheat straw treated at 220{sup 0}C for 3 minutes and an enzyme to substrate ratio of 4%. It has been pointed out the necessity of washing with water the pretreated what straw, in order to remove the biomass degradation products, which have shown an inhibition effect on the yeast. At the best process conditions, a fermentation yield of 95% has been achieved. In the Simultaneous Saccharification and Fermentation process, a global conversion of 92% has been obtained, which corresponds to the production of about 170 grams of ethanol per kilogram of exploded straw. [Italian] Si riportano i risultati di un'attivita' di ricerca finalizzata all'ottimizzazione del processo di produzione di etanolo da paglia di grano. Il processo esaminato consta di un pretrattamento mediante steam explosion della paglia, seguito da idrolisi enzimatica della cellulosa e fermentazione del glucosio ottenuto. Per effettuare l'idrolisi sono stati utilizzati due preparati enzimatici disponibili commercialmente, costituiti da {beta}-glucosidasi, endo-glucanasi ed eso-glucanasi. Per la fermentazione del glucosio negli idrolizzati e' stato impiegato il lievito Saccharomyces cerevisae. E' stata raggiunta un'efficienza massima di idrolisi del 97% utilizzando

Determination of methanol in Iranian herbal distillates.

Science.gov (United States)

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

2016-06-01

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

Experimental investigation two phase flow in direct methanol fuel cells

International Nuclear Information System (INIS)

Mat, M. D.; Kaplan, Y.; Celik, S.; Oeztural, A.

2007-01-01

Direct methanol fuel cells (DMFC) have received many attentions specifically for portable electronic applications since it utilize methanol which is in liquid form in atmospheric condition and high energy density of the methanol. Thus it eliminates the storage problem of hydrogen. It also eliminates humidification requirement of polymeric membrane which is a problem in PEM fuel cells. Some electronic companies introduced DMFC prototypes for portable electronic applications. Presence of carbon dioxide gases due to electrochemical reactions in anode makes the problem a two phase problem. A two phase flow may occur at cathode specifically at high current densities due to the excess water. Presence of gas phase in anode region and liquid phase in cathode region prevents diffusion of fuel and oxygen to the reaction sites thus reduces the performance of the system. Uncontrolled pressure buildup in anode region increases methanol crossover through membrane and adversely effect the performance. Two phase flow in both anode and cathode region is very effective in the performance of DMYC system and a detailed understanding of two phase flow for high performance DMFC systems. Although there are many theoretical and experimental studies available on the DMFC systems in the literature, only few studies consider problem as a two-phase flow problem. In this study, an experimental set up is developed and species distributions on system are measured with a gas chromatograph. System performance characteristics (V-I curves) is measured depending on the process parameters (temperature, fuel ad oxidant flow rates, methanol concentration etc)

Rapid biological oxidation of methanol in the tropical Atlantic: significance as a microbial carbon source

Directory of Open Access Journals (Sweden)

J. L. Dixon

2011-09-01

Full Text Available Methanol is the second most abundant organic gas in the atmosphere after methane, and is ubiquitous in the troposphere. It plays a significant role in atmospheric oxidant chemistry and is biogeochemically active. Large uncertainties exist about whether the oceans are a source or sink of methanol to the atmosphere. Even less is understood about what reactions in seawater determine its concentration, and hence flux across the sea surface interface. We report here concentrations of methanol between 151–296 nM in parts of the oligotrophic North Atlantic, with corresponding microbial uptake rates between 2–146 nM d⁻¹, suggesting turnover times as low as 1 day (1–25 days in surface waters of the oligotrophic tropical North East Atlantic. Methanol is mainly (≥97% used by microbes for obtaining energy in oligotrophic regions, which contrasts with shelf and coastal areas where between 20–50% can be used for cell growth. Comparisons of microbial methanol oxidation rates with parallel determinations of bacterial leucine uptake suggest that methanol contributes on average 13% to bacterial carbon demand in the central northern Atlantic gyre (maximum of 54%. In addition, the contribution that methanol makes to bacterial carbon demand varies as a power function of chlorophyll a concentrations; suggesting for concentrations <0.2 μg l⁻¹ that methanol can make a significant contribution to bacterial carbon demand. However, our low air to sea methanol flux estimates of 7.2–13 μmol m⁻² d⁻¹ suggest that the atmosphere is not a major methanol source. We conclude that there must be a major, as yet unidentified, in situ oceanic methanol source in these latitudes which we suggest is sunlight driven decomposition of organic matter.

Batch extractive distillation for high purity methanol

International Nuclear Information System (INIS)

Zhang Weijiang; Ma Sisi

2006-01-01

In this paper, the application in chemical industry and microelectronic industry, market status and the present situation of production of high purity methanol at home and abroad were introduced firstly. Purification of industrial methanol for high purity methanol is feasible in china. Batch extractive distillation is the best separation technique for purification of industrial methanol. Dimethyl sulfoxide was better as an extractant. (authors)

Recycling of greenhouse gases via methanol

Energy Technology Data Exchange (ETDEWEB)

Bill, A [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Eliasson, B; Kogelschatz, U [ABB Corporate Research Center, Baden-Daettwil (Switzerland)

1997-06-01

Greenhouse gas emissions to the atmosphere can be mitigated by using direct control technologies (capture, disposal or chemical recycling). We report on carbon dioxide and methane recycling with other chemicals, especially with hydrogen and oxygen, to methanol. Methanol synthesis from CO{sub 2} is investigated on various catalysts at moderate pressures ({<=}30 bar) and temperatures ({<=}300{sup o}C). The catalysts show good methanol activities and selectivities. The conversion of CO{sub 2} and CH{sub 4} to methanol is also studied in a silent electrical discharge at pressures of 1 to 4 bar and temperatures close to room temperature. Methanol yields are given for mixtures of CO{sub 2}/H{sub 2}, CH{sub 4}/O{sub 2} and also for CH{sub 4} and air mixtures. (author) 2 figs., 5 refs.

Final environmental assessment for the Liquid Phase Methanol (LPMEOH trademark) Project

International Nuclear Information System (INIS)

1995-06-01

The proposed project is to demonstrate on a commercial scale the production of methanol from coal-derived synthesis gas using the LPMEOH trademark process. The methanol produced during this demonstration will be used as a chemical feedstock (on-site) and/or as an alternative fuel in stationary and transportation applications (off-site). In addition, the production of dimethyl ether (DME) as a mixed co-product with methanol may be demonstrated for a six month period under the proposed project pending the results of laboratory/pilot-scale research on scale-up. The DME would be used as fuel in on-site boilers. The proposed LPMEOH facility would occupy approximately 0.6 acres of the 3,890-acre Eastman Chemical facility in Kingsport, TN. The effects of the proposed project include changes in air emissions, wastewater discharge, cooling water discharge, liquid waste quantities, transportation activities, socioeconomic effects, and quantity of solids for disposal. No substantive negative impacts or environmental concerns were identified

Methanol utilizing Desulfotomaculum species utilizes hydrogen in a methanol-fed sulfate-reducing bioreactor.

Science.gov (United States)

Balk, Melike; Weijma, Jan; Goorissen, Heleen P; Ronteltap, Mariska; Hansen, Theo A; Stams, Alfons J M

2007-01-01

A sulfate-reducing bacterium, strain WW1, was isolated from a thermophilic bioreactor operated at 65 degrees C with methanol as sole energy source in the presence of sulfate. Growth of strain WW1 on methanol or acetate was inhibited at a sulfide concentration of 200 mg l(-1), while on H2/CO2, no apparent inhibition occurred up to a concentration of 500 mg l(-1). When strain WW1 was co-cultured under the same conditions with the methanol-utilizing, non-sulfate-reducing bacteria, Thermotoga lettingae and Moorella mulderi, both originating from the same bioreactor, growth and sulfide formation were observed up to 430 mg l(-1). These results indicated that in the co-cultures, a major part of the electron flow was directed from methanol via H2/CO2 to the reduction of sulfate to sulfide. Besides methanol, acetate, and hydrogen, strain WW1 was also able to use formate, malate, fumarate, propionate, succinate, butyrate, ethanol, propanol, butanol, isobutanol, with concomitant reduction of sulfate to sulfide. In the absence of sulfate, strain WW1 grew only on pyruvate and lactate. On the basis of 16S rRNA analysis, strain WW1 was most closely related to Desulfotomaculum thermocisternum and Desulfotomaculum australicum. However, physiological properties of strain WW1 differed in some aspects from those of the two related bacteria.

Solvation structures of lithium halides in methanol–water mixtures

International Nuclear Information System (INIS)

Sarkar, Atanu; Dixit, Mayank Kumar; Tembe, B.L.

2015-01-01

Highlights: • Potentials of mean force for Li + -halides are calculated in methanol–water mixtures. • Stable CIP for x methanol = 1.0 becomes unstable at and below x methanol = 0.75. • The Li + ion is preferentially solvated by methanol molecules. • The halide ions are preferentially solvated by water molecules. - Abstract: The potentials of mean force (PMFs) for the ion pairs, Li + −Cl − , Li + −Br − and Li + −I − have been calculated in five methanol–water compositions. The results obtained are verified by trailing the trajectories and calculating the ion pair distance residence times. Local structures around the ions are studied using the radial distribution functions, density profiles, orientational correlation functions, running coordination numbers and excess coordination numbers. The major change in PMF is observed as the methanol mole fraction (x methanol ) is changed from 1.0 to 0.75. The stable contact ion pair occurring for x methanol = 1.0 becomes unstable at and below x methanol = 0.75. The preferential solvation data show that the halide ions are always preferentially solvated by water molecules. Although the lithium ion is preferentially solvated by methanol molecules, there is significant affinity towards water molecules as well

KELIMPAHAN STOK SUMBER DAYA IKAN DEMERSAL DI PERAIRAN SUB AREA LAUT JAWA

Directory of Open Access Journals (Sweden)

Badrudin Badrudin

2016-06-01

Full Text Available Tulisan ini menyajikan data dan informasi tentang present status perikanan demersal di Laut Jawa, dan tingkat pemanfaatan sumber daya ikan di sub area Laut Jawa yang tidak merata. Data yang dianalisis merupakan sebagian hasil survei Balai Riset Perikanan Laut di Pelabuhan Perikanan Pantai Tegal pada tahun 2010 dan pada periode tahun sebelumnya. Eksploitasi sumber daya ikan demersal di perairan Laut Jawa sudah berlangsung sejak lama dan mencapai puncaknya pada sekitar tahun 1970-an di mana trawl dioperasikan secara intensif terutama di sepanjang pantai utara Jawa. Tingginya tekanan penangkapan di perairan pantai sampai kedalaman 40-an m telah menyebabkan menurunnya kelimpahan sumber daya, sebagaimana tampak pada hasil tangkapan cantrang kecil dan jaring arad yang dioperasikan secara harian. Kelimpahan dan ukuran individu ikan demersal di kawasan yang lebih dalam tampak cukup besar sebagaimana tercermin dari hasil tangkapan cantrang besar yang dioperasikan lebih lama. Dari fenomena tersebut dapat diduga bahwa sumber daya ikan demersal di perairan pantai sudah mengalami tangkap lebih (overfishing yang mengarah kepada penurunan stok atau bahkan depleted. Kegiatan penangkapan ikan di perairan yang lebih dalam di mana tekanan penangkapan relatif lebih rendah tampak memberikan keuntungan.   Based on data analysis and information collected, this paper describes the present status of demersal fisheries in the Java Sea and the uneven level of exploitation of the fish resources in the Java Sea sub areas. Data analyzed provide part of research results carried out by the Research Institute for Marine Fisheries. Data were obtained from a number of surveis carried out in Tegal landing place in 2010 and from the previous years. Demersal resources in the Java Sea have been exploited for years, where high fishing intensity occurred in the north coast of Java. High fishing pressure in the coastal waters lead to the decreasing fish resources abundance, as

Study of the influence of surfactants on the activity coefficients and mass transfer coefficients of methanol in aqueous mixtures by reversed-flow gas chromatography.

Science.gov (United States)

Kotsalos, Efthimios; Brezovska, Boryana; Sevastos, Dimitrios; Vagena, Artemis; Koliadima, Athanasia; Kapolos, John; Karaiskakis, George

2017-11-17

This work focuses on the influences of surfactants on the activity coefficients, γ, of methanol in binary mixtures with water, as well as on the mass transfer coefficients, k c , for the evaporation of methanol, which is a ubiquitous component in the troposphere, from mixtures of methanol with water at various surfactant's and methanol's concentrations. The technique used is the Reversed-Flow Gas Chromatography (R.F.G.C.), a version of Inverse Gas Chromatography, which allows determining both parameters by performing only one experiment for the k c parameter and two experiments for the γ parameter. The k c and γ values decrease in the presence of the three surfactants used (CTAB, SDS, TRITON X-100) at all methanol's and surfactant's concentrations. The decrease in the methanol's molar fraction, at constant number of surfactant films leads to a decrease in the k c and γ values, while the decrease in the surfactant's concentration, at constant methanol's molar fraction leads to an increase in both the k c and γ parameters. Mass transfer coefficients for the evaporation of methanol at the surfactant films, are also calculated which are approximately between 4 and 5 orders of magnitude larger than the corresponding mass transfer coefficients at the liquid films. Finally, thicknesses of the boundary layer of methanol in the mixtures of methanol with water were determined. The quantities found are compared with those given in the literature or calculated theoretically using various empirical equations. The precision of the R.F.G.C. method for measuring γ and k c parameters is approximately high (94.3-98.0%), showing that R.F.G.C. can be used with success not only for the thermodynamic study of solutions, but also for the interphase transport. Copyright © 2017 Elsevier B.V. All rights reserved.

Pengelolaan Sumberdaya Air untuk Pengembangan Pariwisata di Pulau Pari, Kepulauan Seribu, DKI Jakarta

Directory of Open Access Journals (Sweden)

Roland Sinulingga

2016-09-01

Full Text Available ABSTRAK Penelitian bertujuan untuk (a menganalisis kondisi ketersediaan air di Pulau Pari, (b menganalisis kondisi kualitas air di Pulau Pari, (c menganalisis kebutuhan air dan proyeksinya untuk masa yang akan datang di Pulau Pari, dan (d merumuskan strategi pengelolaan sumberdaya air untuk pariwisata di Pulau Pari. Metode penelitian terdiri atas perhitungan neraca air, kebutuhan air, metode geometrik, analisis deskriptif, dan analisis SWOT. Pengambilan sampel air dan penduduk menggunakan metode purposive, sedangkan sampel wisatawan menggunakan metode accidental random sampling. Hasil akhir penelitian ketersediaan airtanah di Pulau Pari sebesar 290000,48 m3/tahun. Kualitas airtanah di lokasi penelitian tergolong baik. Besarnya kebutuhan air tahun 2013 sebesar 46381,947 m3/tahun. Pada tahun 2018 menjadi 54443,953 m3/tahun dan pada tahun 2023 mengalami peningkatan menjadi 63548,472 m3/tahun. Prioritas utama strategi pengelolaan sumberdaya air untuk pariwisata yaitu membuat kebijakan pembatasan pengunjung agar kelestarian pulau dan sumberdaya air tetap terjaga.   ABSTRACT This study aims to (a analyze water availability conditions in Pari Island, (b analyze the water quality conditions in Pari Island, (c analyze water demand and water projections for the future in Pari Island, and (d formulate strategies management water resources for tourism in Pari Island. The research method consists of the calculation of the water balance, water requirements, geometric methods, descriptive analysis, and SWOT analysis. Water sampling and settlement using purposive method, tourist’s samples using accidental random sampling. The final results of The amount of soil water availability in Pari Island of 290000,48 m3 / year. Groundwater quality in the study area are classified as good. The amount of water demand in 2013 amounted to 46381,947 m3 / year. In 2018 became 54443,953 m3 / year and in 2023 increased to 63548,472 m3 / year. First priority water resource

Exergetic analysis and optimization of a solar-powered reformed methanol fuel cell micro-powerplant

Science.gov (United States)

Hotz, Nico; Zimmerman, Raúl; Weinmueller, Christian; Lee, Ming-Tsang; Grigoropoulos, Costas P.; Rosengarten, Gary; Poulikakos, Dimos

The present study proposes a combination of solar-powered components (two heaters, an evaporator, and a steam reformer) with a proton exchange membrane fuel cell to form a powerplant that converts methanol to electricity. The solar radiation heats up the mass flows of methanol-water mixture and air and sustains the endothermic methanol steam reformer at a sufficient reaction temperature (typically between 220 and 300 °C). In order to compare the different types of energy (thermal, chemical, and electrical), an exergetic analysis is applied to the entire system, considering only the useful part of energy that can be converted to work. The effect of the solar radiation intensity and of different operational and geometrical parameters like the total inlet flow rate of methanol-water mixture, the size of the fuel cell, and the cell voltage on the performance of the entire system is investigated. The total exergetic efficiency comparing the electrical power output with the exergy input in form of chemical and solar exergy reaches values of up to 35%, while the exergetic efficiency only accounting for the conversion of chemical fuel to electricity (and neglecting the 'cost-free' solar input) is increased up to 59%. At the same time, an electrical power density per irradiated area of more than 920 W m -2 is obtained for a solar heat flux of 1000 W m -2.

Reversible Activation of Halophilic β-lactamase from Methanol-Induced Inactive Form: Contrast to Irreversible Inactivation of Non-Halophilic Counterpart.

Science.gov (United States)

Tokunaga, Hiroko; Maeda, Junpei; Arakawa, Tsutomu; Tokunaga, Masao

2017-06-01

Effects of a water-miscible organic solvent, methanol, on the structure and activity of halophilic β-lactamase derived from Chromohalobacter sp.560 (HaBla), were investigated by means of circular dichroism (CD) measurement and enzymatic activity determination. Beta-lactamase activity was enhanced about 1.2-fold in the presence of 10-20% methanol. CD measurement of HaBla revealed different structures depending on the methanol concentration: native-like active form (Form I) in 10-20% methanol and methanol-induced inactive form at higher concentration (Form II in 40-60% and Form III in 75-80% methanol). Incubation of HaBla with 40% methanol led to the complete loss of activity within ~80 min accompanied by the formation of Form II, whose activity was recovered promptly up to ~80% of full activity upon dilution of the methanol concentration to 10%. In addition, when the protein concentration was sufficiently high (e.g., 0.7 mg/ml), HaBla activity of Form III in 75% methanol could be recovered in the same way (with slightly slower recovery rate), upon dilution of the methanol concentration. In contrast, non-halophilic β-lactamase from Escherichia coli K12 strain MG1655 (EcBla) was irreversibly denatured in the presence of 40% methanol. HaBla showed remarkable ability to renature from the methanol-induced inactive states.

Effect of methanol ratio in mixed solvents on optical properties and wettability of ZnO films by cathodic electrodeposition

International Nuclear Information System (INIS)

Zhang, Miao; Xu, Kai; Jiang, Xishun; Yang, Lei; He, Gang; Song, Xueping; Sun, Zhaoqi; Lv, Jianguo

2014-01-01

Highlights: • Different surface morphologies of ZnO films were prepared by cathodic electrodeposition. • The surface morphologies are controlled through add different ratio methanol to electrolyte. • The morphology changes from nanorods with hexagonal structure to net-like nanostructure. • The wettability of films shows obvious change with increasing methanol ratio. • The maximum light-induced CA change has been observed with the methanol ratio of 0.8. - Abstract: ZnO thin films were prepared in the electrolyte with different methanol ratio by cathodic electrodeposition method. Microstructure, surface morphology, optical properties and wettability of the thin films were investigated by X-ray diffractometer, field-emission scanning electron microscope, ultraviolet–visible spectroscope, fluorescence spectrometer and water contact angle apparatus. Increase of methanol ratio in the solvents may restrain the (0 0 2) plane preferential orientation in some extent. Change of current density curves with the ratio of methanol in the solution play a vital role on electrochemical reaction kinetics, microstructure and/or surface morphology of ZnO thin films. With the methanol ratio increase from 0 to 0.8, the surface morphology changes from nanorods to net-like nanostructure. The adsorbed NO 3 − ions on the polar planes hinder the crystal growth along the c-axis and redirect the growth direction along the nonpolar planes. The maximum and minimum band gaps have been obtained in the ZnO thin films with the methanol ratio of 0.4 and 0.6, respectively. Change of contact angle before UV irradiation may be related to surface morphology and oxygen vacancies. The maximum light-induced water contact angle change has been observed in the sample with the methanol ratio of 0.8. The results may be attributed to the higher surface roughness and net-like morphology

Effect of methanol ratio in mixed solvents on optical properties and wettability of ZnO films by cathodic electrodeposition

Energy Technology Data Exchange (ETDEWEB)

Zhang, Miao; Xu, Kai; Jiang, Xishun; Yang, Lei; He, Gang; Song, Xueping [School of Physics and Material Science, Anhui University, Hefei 230601 (China); Sun, Zhaoqi, E-mail: szq@ahu.edu.cn [School of Physics and Material Science, Anhui University, Hefei 230601 (China); Lv, Jianguo, E-mail: lvjg1@163.com [School of Electronic and Information Engineering, Hefei Normal University, Hefei 230601 (China)

2014-12-05

Highlights: • Different surface morphologies of ZnO films were prepared by cathodic electrodeposition. • The surface morphologies are controlled through add different ratio methanol to electrolyte. • The morphology changes from nanorods with hexagonal structure to net-like nanostructure. • The wettability of films shows obvious change with increasing methanol ratio. • The maximum light-induced CA change has been observed with the methanol ratio of 0.8. - Abstract: ZnO thin films were prepared in the electrolyte with different methanol ratio by cathodic electrodeposition method. Microstructure, surface morphology, optical properties and wettability of the thin films were investigated by X-ray diffractometer, field-emission scanning electron microscope, ultraviolet–visible spectroscope, fluorescence spectrometer and water contact angle apparatus. Increase of methanol ratio in the solvents may restrain the (0 0 2) plane preferential orientation in some extent. Change of current density curves with the ratio of methanol in the solution play a vital role on electrochemical reaction kinetics, microstructure and/or surface morphology of ZnO thin films. With the methanol ratio increase from 0 to 0.8, the surface morphology changes from nanorods to net-like nanostructure. The adsorbed NO{sub 3}{sup −} ions on the polar planes hinder the crystal growth along the c-axis and redirect the growth direction along the nonpolar planes. The maximum and minimum band gaps have been obtained in the ZnO thin films with the methanol ratio of 0.4 and 0.6, respectively. Change of contact angle before UV irradiation may be related to surface morphology and oxygen vacancies. The maximum light-induced water contact angle change has been observed in the sample with the methanol ratio of 0.8. The results may be attributed to the higher surface roughness and net-like morphology.

Thermodynamique statistique résumés de cours et problèmes résolus

CERN Document Server

Chahine, C

1976-01-01

Le présent ouvrage est conçu pour une initiation à la thermodynamique statistique en présentant un très grand nombre d'applications sous forme de problèmes résolus, et en donnant des résumés de cours constitués de l'essentiel des résultats théoriques nécessaires pour traiter les applications chaque fois qu'est abordé un nouveau domaine. Partant d'un niveau élémentaire et rédigé de façon très progressive, ce livre qui se suffit à lui-même, permet de saisir l'aspect physique des phénomènes, et de faire le lien entre les statistiques élémentaires et les statistiques de Gibbs. Le lecteur pourra, soit résoudre effectivement les problèmes sans avoir recours à la solution et tirer alors tout le bénéfice d'une recherche personnelle, soit lire l'ensemble de l'énoncé et de la solution qui sont très détaillés, et forment ainsi un exposé très clair. L'ouvrage, qui développe principalement l'aspect physique des phénomènes, intéresse les étudiants en physique dès la 1ère année ...

Methanol ice co-desorption as a mechanism to explain cold methanol in the gas-phase

Science.gov (United States)

Ligterink, N. F. W.; Walsh, C.; Bhuin, R. G.; Vissapragada, S.; van Scheltinga, J. Terwisscha; Linnartz, H.

2018-05-01

Context. Methanol is formed via surface reactions on icy dust grains. Methanol is also detected in the gas-phase at temperatures below its thermal desorption temperature and at levels higher than can be explained by pure gas-phase chemistry. The process that controls the transition from solid state to gas-phase methanol in cold environments is not understood. Aims: The goal of this work is to investigate whether thermal CO desorption provides an indirect pathway for methanol to co-desorb at low temperatures. Methods: Mixed CH3OH:CO/CH4 ices were heated under ultra-high vacuum conditions and ice contents are traced using RAIRS (reflection absorption IR spectroscopy), while desorbing species were detected mass spectrometrically. An updated gas-grain chemical network was used to test the impact of the results of these experiments. The physical model used is applicable for TW Hya, a protoplanetary disk in which cold gas-phase methanol has recently been detected. Results: Methanol release together with thermal CO desorption is found to be an ineffective process in the experiments, resulting in an upper limit of ≤ 7.3 × 10-7 CH3OH molecules per CO molecule over all ice mixtures considered. Chemical modelling based on the upper limits shows that co-desorption rates as low as 10-6 CH3OH molecules per CO molecule are high enough to release substantial amounts of methanol to the gas-phase at and around the location of the CO thermal desorption front in a protoplanetary disk. The impact of thermal co-desorption of CH3OH with CO as a grain-gas bridge mechanism is compared with that of UV induced photodesorption and chemisorption.

A novel method of methanol concentration control through feedback of the amplitudes of output voltage fluctuations for direct methanol fuel cells

International Nuclear Information System (INIS)

An, Myung-Gi; Mehmood, Asad; Hwang, Jinyeon; Ha, Heung Yong

2016-01-01

This study proposes a novel method for controlling the methanol concentration without using methanol sensors for DMFC (direct methanol fuel cell) systems that have a recycling methanol-feed loop. This method utilizes the amplitudes of output voltage fluctuations of DMFC as a feedback parameter to control the methanol concentration. The relationship between the methanol concentrations and the amplitudes of output voltage fluctuations is correlated under various operating conditions and, based on the experimental correlations, an algorithm to control the methanol concentration with no sensor is established. Feasibility tests of the algorithm have been conducted under various operating conditions including varying ambient temperature with a 200 W-class DMFC system. It is demonstrated that the sensor-less controller is able to control the methanol-feed concentration precisely and to run the DMFC systems more energy-efficiently as compared with other control systems. - Highlights: • A new sensor-less algorithm is proposed to control the methanol concentration without using a sensor. • The algorithm utilizes the voltage fluctuations of DMFC as a feedback parameter to control the methanol feed concentration. • A 200 W DMFC system is operated to evaluate the validity of the sensor-less algorithm. • The algorithm successfully controls the methanol feed concentration within a small error bound.

Thermophysical properties of binary mixtures of {l_brace}ionic liquid 2-hydroxy ethylammonium acetate + (water, methanol, or ethanol){r_brace}

Energy Technology Data Exchange (ETDEWEB)

Alvarez, Victor H. [School of Chemical Engineering, State University of Campinas (UNICAMP), P.O. Box 6066, 13083-970 Campinas-SP (Brazil); Chemical Engineering Department, ETSE, University of Santiago de Compostela (USC), P.O. Box 15782, Santiago de Compostela (Spain); Mattedi, Silvana [Chemical Engineering Department, Polytechnic School, Federal University of Bahia (UFBA), 40210-630 Salvador-BA (Brazil); Martin-Pastor, Manuel [Unidade de Resonancia Magnetica, RIAIDT, edif. CACTUS, University of Santiago de Compostela (USC), P.O. Box 15706, Santiago de Compostela (Spain); Aznar, Martin [School of Chemical Engineering, State University of Campinas (UNICAMP), P.O. Box 6066, 13083-970 Campinas-SP (Brazil); Iglesias, Miguel, E-mail: miguel.iglesias@usc.es [Chemical Engineering Department, ETSE, University of Santiago de Compostela (USC), P.O. Box 15782, Santiago de Compostela (Spain)

2011-07-15

Research highlights: > This paper reports the density and speed of sound data of binary mixtures {l_brace}2-hydroxy ethylammonium acetate + (water, or methanol, or ethanol){r_brace} measured between the temperatures (298.15 and 313.15) K at atmospheric pressure. > The aggregation, dynamic behavior, and hydrogen-bond network were studied using thermo-acoustic, X-ray, and NMR techniques. > The Peng-Robinson equation of state, coupled with the Wong-Sandler mixing rule using the COSMO-SAC model predicted the density of the solutions with relative mean deviations below than 3.0%. - Abstract: In this work, density and speed of sound data of binary mixtures of an ionic liquid consisting of {l_brace}2-hydroxy ethylammonium acetate (2-HEAA) + (water, methanol, or ethanol){r_brace} have been measured throughout the entire concentration range, from the temperature of (288.15 to 323.15) K at atmospheric pressure. The excess molar volumes, variations of the isentropic compressibility, the apparent molar volume, isentropic apparent molar compressibility, and thermal expansion coefficient were calculated from the experimental data. The excess molar volumes were negative throughout the whole composition range. Compressibility data in combination with low angle X-ray scattering and NMR measurements proved that the presence of micelles formed due to ion pair interaction above a critical concentration of the ionic liquid in the mixtures. The Peng-Robinson equation of state coupled with the Wong-Sandler mixing rule and COSMO-SAC model was used to predict densities and the calculated deviations were lower than 3%, for binary mixtures in all composition range.

Surrogate alcohol containing methanol, social deprivation and public health in Novosibirsk, Russia.

Science.gov (United States)

Neufeld, Maria; Lachenmeier, Dirk; Hausler, Thomas; Rehm, Jürgen

2016-11-01

Surrogate alcohol, i.e. alcohol not intended or not officially intended for human consumption, continues to play an important role in alcohol consumption in Russia, especially for people with alcohol dependence. Among the different types of surrogate alcohol, there are windshield washer antifreeze liquids; these products are the cheapest kinds of non-beverage alcohol available and thus likely to be used by the most deprived and marginalised groups such as homeless people with alcohol dependence. Although it is well known, that non-beverage alcohol is used for consumption by various groups in Russia, and although there are laws to prohibit the use of methanol as part of windshield washer antifreeze liquids for the very reason that such products could be used as surrogate alcohol, we detected products in retail sale which were a mix of water and methanol only. Methanol poses serious health threats including blindness and death, and there had been repeated methanol deaths from surrogate alcohol in Russia over the last years. If law-enforcement does not change for surrogate products, we can expect more methanol-resulting deaths in the most deprived and marginalized groups of people with alcohol dependence in Russia. In addition, ingredients with questionable safety profiles such as formic acid should also be prohibited in non-beverage alcohol products that are likely to be consumed as surrogate alcohol. Copyright © 2016. Published by Elsevier B.V.

Production of methanol/DME from biomass

DEFF Research Database (Denmark)

Ahrenfeldt, Jesper; Henriksen, Ulrik Birk; Münster-Swendsen, Janus

In this project the production of DME/methanol from biomass has been investigated. Production of DME/methanol from biomass requires the use of a gasifier to transform the solid fuel to a synthesis gas (syngas) - this syngas can then be catalytically converted to DME/methanol. Two different gasifier...... cleaning. This was proved by experiments. Thermodynamic computer models of DME and methanol plants based on using the Two-Stage Gasification concept were created to show the potential of such plants. The models showed that the potential biomass to DME/methanol + net electricity energy efficiency was 51...... gasification, but little information exists on using these types of gasifiers for biomass gasification. The experiments performed provided quantitative data on product and gas composition as a function of operation conditions. Biomass can be gasified with less oxygen consumption compared to coal. The organic...

Dosage of high COD industrial wastewaters as an external carbon source in the pre-denitrification step of activated sludge plants; Utilizzo di reflui industriali a elevato COD come fonte esterna di carbonio in pre-denitrificazione negli impianti a fanghi attivi

Energy Technology Data Exchange (ETDEWEB)

Bertanza, G.; Collivignarelli, C.; Pedrazzani, R. [Brescia Univ., Brescia (Italy). Facolta' di Ingegneria, Dipt. di Ingegneria Civile

2001-04-01

In pre-denitrification plants, the organic carbon shortage in the influent wastewater can inhibit the denitrification process. In this case, the dosage of organic substrates can be considered, when the F/M ratio in the nitrification stage is adequate. Beside commonly available substances (acetic acid, methanol etc.) industrial wastewaters can be dosed. This research was aimed to assess the feasibility of this alternative, by testing several industrial wastewaters in addition to real municipal wastewater. The experiment consisted in running a continuous-flow activated sludge pilot plant and in carrying out NUR (Nitrogen Uptake Rate) tests. The studied wastewaters derive from the food industry and, more precisely, from cocoa working and from the cold drink industry. Results were compared with two reference situations (dosage of sodium acetate and of an available organic solution). [Italian] Negli impianti con pre-denitrificazione, il processo di denitrificazione puo' essere inibito dalla carenza di carbonio organico nel liquame influente. Un rimedio (applicabile qualora il carico del fango in nitrificazione sia compatibile) consiste nel dosaggio di substrati carboniosi. Accanto alle soluzioni commercializzate (acido acetico, metanolo, ecc.) e' possibile dosare reflui industriali aventi caratteristiche adeguate. Nel presente studio si e' voluta verificare tale alternativa mediante una sperimentazione svolta su liquame fognario a cui sono stati aggiunti, di volta in volta, diversi substrati carboniosi. Le prove sono state effettuate sia in continuo (mediante l'impiego di un impianto pilota a fanghi attivi) sia in batch (test di NUR - Nitrogen Uptake Rate). I reflui studiati originano dall'industria alimentare, in particolare, dalla laovrazione del cacao e dalla produzione di bevande analcoliche. I risultati sono stati confrontati con due situazioni di riferimento (dosaggio di acetato di sodio e di una soluzione carboniosa disponibile in

Catalytic Hydrogenation of CO2 to Methanol: Study of Synergistic Effect on Adsorption Properties of CO2 and H2 in CuO/ZnO/ZrO2 System

Directory of Open Access Journals (Sweden)

Chunjie Huang

2015-11-01

Full Text Available A series of CuO/ZnO/ZrO2 (CZZ catalysts with different CuO/ZnO weight ratios have been synthesized by citrate method and tested in the catalytic hydrogenation of CO2 to methanol. Experimental results showed that the catalyst with the lowest CuO/ZnO weight ratio of 2/7 exhibited the best catalytic performance with a CO2 conversion of 32.9%, 45.8% methanol selectivity, and a process delivery of 193.9 gMeOH·kgcat−1·h−1. A synergetic effect is found by systematic temperature-programmed-desorption (TPD studies. Comparing with single and di-component systems, the interaction via different components in a CZZ system provides additional active sites to adsorb more H2 and CO2 in the low temperature range, resulting in higher weight time yield (WTY of methanol.

Characteristics of a direct methanol fuel cell system with the time shared fuel supplying approach

International Nuclear Information System (INIS)

Na, Youngseung; Kwon, Jungmin; Kim, Hyun; Cho, Hyejung; Song, Inseob

2013-01-01

DMFC (direct methanol fuel cell) systems usually employ two pumps for supplying the methanol solution. The conventional system configuration, however, may bring about free flow from the methanol reservoir and malfunctions in the self-priming of the pumps. When instruments such as check valves and pressure regulators are applied, they result in excessive weight and control system malfunctions. In this paper, a light and robust DMFC system is proposed. By using the time sharing approach to supply fuel with a 3-way valve, free flow does not occur because only one inlet is opened at one time which means that both the circulation flow from gas liquid separator and the fuel flow from the methanol cartridge are not allowed to be opened at same time. As a result, back flow and self-priming problems do not occur. This makes the system stable and robust due to the removal of both the check valves and the fluctuation from unstable back pressure. Stabilized system doesn't need excessive battery buffering and recycling water any more, which are responsible for the heavy system. The proposed system performs the same level of power and efficiency with the conventional system. Adaptability is also carried out in various environmental temperature conditions. - Highlights: ►A light and robust DMFC system is proposed. ► The circulation pump is able to self-prime by itself after long term storage. ► The time sharing approach to supply fuel enables to control the methanol concentration precisely. ► The methanol concentration is controlled without free flow and the back flow from the fuel feeding pump. ► The excessive buffer of the batteries and the recycling water level are reduced

La stima dei fabbisogni irrigui a scala aziendale e consortile mediante tecniche di Osservazione della Terra

Directory of Open Access Journals (Sweden)

Filiberto Altobelli

2012-04-01

Full Text Available Le applicazioni agrometeorologiche per la gestione delle colture in pieno campo e l’utilizzo di nuove tecnologie di monitoraggio sono sempre più diffuse e si concretizzano anche attraverso lo sviluppo di progetti di ricerca internazionali orientati all’implementazione di servizi operativi. Particolare rilevanza assume il programma Global Monitoring for Enviroment and Security (GMES, che supporta lo sviluppo di capacità e servizi di monitoraggio globale attraverso tecniche di Osservazione della Terra. Irrigation  needs  estimation  at  farm  and  district  level  by Earth Observation techniquesSIRIUS  (Sustainable  Irrigation  water  management  and  River-basin  governance:  Implementing  User-driven  Services  is  a research project funded by EU FP7 in the GMES framework supporting the development of monitoring services through remote sensing and ICT technologies to deliver the service to the  final  users.  SIRIUS  is  developing  efficient  water  resource management  services  in  support  of  food  production  in  water-scarce  environments.  It  addresses  water  governance  and management  in  accordance  with  the  vision  of  bridging  and integrating sustainable development and economic competi-tiveness. The project is developing new services for water man-agers and food producers, and a range of additional information products in support of sustainable irrigation water use and management under conditions of water scarcity and drought.

La stima dei fabbisogni irrigui a scala aziendale e consortile mediante tecniche di Osservazione della Terra

Directory of Open Access Journals (Sweden)

Filiberto Altobelli

2012-04-01

Full Text Available Le applicazioni agrometeorologiche per la gestione delle colture in pieno campo e l’utilizzo di nuove tecnologie di monitoraggio sono sempre più diffuse e si concretizzano anche attraverso lo sviluppo di progetti di ricerca internazionali orientati all’implementazione di servizi operativi. Particolare rilevanza assume il programma Global Monitoring for Enviroment and Security (GMES, che supporta lo sviluppo di capacità e servizi di monitoraggio globale attraverso tecniche di Osservazione della Terra.   Irrigation  needs  estimation  at  farm  and  district  level  by Earth Observation techniques SIRIUS  (Sustainable  Irrigation  water  management  and  River-basin  governance:  Implementing  User-driven  Services  is  a research project funded by EU FP7 in the GMES framework supporting the development of monitoring services through remote sensing and ICT technologies to deliver the service to the  final  users.  SIRIUS  is  developing  efficient  water  resource management  services  in  support  of  food  production  in  water-scarce  environments.  It  addresses  water  governance  and management  in  accordance  with  the  vision  of  bridging  and integrating sustainable development and economic competi-tiveness. The project is developing new services for water man-agers and food producers, and a range of additional information products in support of sustainable irrigation water use and management under conditions of water scarcity and drought.

Estimation of the nucleation kinetics for the anti-solvent crystallisation of paracetamol in methanol/water solutions

Science.gov (United States)

Ó'Ciardhá, Clifford T.; Frawley, Patrick J.; Mitchell, Niall A.

2011-08-01

In this work the primary nucleation kinetics have been estimated for the anti-solvent crystallisation of paracetamol in methanol-water solutions from metastable zone widths (MSZW) and induction times at 25 °C. Laser back-scattering via a focused beam reflectance Measurement (FBRM ®) is utilised to detect the onset of nucleation. The theoretical approach of Kubota was employed to estimate the nucleation kinetics, which accounts for the sensitivity of the nucleation detection technique. This approach is expanded in this work to analyse the induction time for an anti-solvent crystallisation process. Solvent composition is known to have a significant impact on the measured induction times and MSZW. The induction time in this paper was measured from 40% to 70% mass water and the MSZW is measured from 40% to 60% mass water. The primary focus of the paper was to gauge the extent of how solvent composition affects nucleation kinetics so that this effect may be incorporated into a population balance model. Furthermore, the effects of solvent composition on the estimated nucleation rates are investigated. The primary nucleation rates were found to decrease with dynamic solvent composition, with the extent of their reduction linked to the gradient of the solubility curve. Finally, both MSZW and induction time methods have been found to produce similar estimates for the nucleation parameters.

Modeling and simulation of an isothermal reactor for methanol steam reforming

Directory of Open Access Journals (Sweden)

Raphael Menechini Neto

2014-04-01

Full Text Available Due to growing electricity demand, cheap renewable energy sources are needed. Fuel cells are an interesting alternative for generating electricity since they use hydrogen as their main fuel and release only water and heat to the environment. Although fuel cells show great flexibility in size and operating temperature (some models even operate at low temperatures, the technology has the drawback for hydrogen transportation and storage. However, hydrogen may be produced from methanol steam reforming obtained from renewable sources such as biomass. The use of methanol as raw material in hydrogen production process by steam reforming is highly interesting owing to the fact that alcohol has the best hydrogen carbon-1 ratio (4:1 and may be processed at low temperatures and atmospheric pressures. They are features which are desirable for its use in autonomous fuel cells. Current research develops a mathematical model of an isothermal methanol steam reforming reactor and validates it against experimental data from the literature. The mathematical model was solved numerically by MATLAB® and the comparison of its predictions for different experimental conditions indicated that the developed model and the methodology for its numerical solution were adequate. Further, a preliminary analysis was undertaken on methanol steam reforming reactor project for autonomous fuel cell.

NMR studies on graphite-methanol system

International Nuclear Information System (INIS)

El-Akkad, T.M.

1977-01-01

The nuclear magnetic relaxation times for protons of methanol on graphite have been studied. The perpendicular and the transversal magnetization as a function of temperature were measured. The results show that the presence of graphite slowed down the methanol movement compared with that in the pure alcohol, and that the methanol molecules are attached to the graphite surface via methyl groups. (author)

Methanol utilizing Desulfotomaculum species utilizes hydrogen in a methanol-fed sulfate-reducing bioreactor

NARCIS (Netherlands)

Balk, M.; Weijma, J.; Goorissen, H.P.; Ronteltap, M.; Hansen, T.A.; Stams, A.J.M.

2007-01-01

A sulfate-reducing bacterium, strain WW1, was isolated from a thermophilic bioreactor operated at 65 degrees C with methanol as sole energy source in the presence of sulfate. Growth of strain WW1 on methanol or acetate was inhibited at a sulfide concentration of 200 mg l(-1), while on H-2/CO2, no

The adsorption of methanol and water on SAPO-34: in situ and ex situ X-ray diffraction studies

DEFF Research Database (Denmark)

Wragg, David S.; Johnsen, Rune; Norby, Poul

2010-01-01

The adsorption of methanol on SAPO-34 has been studied using a combination of in situ synchrotron powder X-ray diffraction to follow the process and ex situ high resolution powder diffraction to determine the structure. The unit cell volume of SAPO-34 is found to expand by 0.5% during methanol ad...

A model for the transfer of 137Cs from the water to the phytoplankton and simulation of laboratory experiments

International Nuclear Information System (INIS)

Smitz, J.S.; Everbecq, E.; Comeliau, B.

1987-01-01

Modelisation of the contamination/decontamination phenomenon of the water/algae Scenedesmus system by Cs-137 has a double purpose: help to quantity the different factors which influence the contamination/decontamination of the algae and to show the influence of the different experimental conditions. A simple model is developed using the conservation equations for the water, the algae biomass and Cs-137. It is supposed that the contamination is an adsorption phenomenon. This model represents satisfactorily the laboratory experiments and explains some curious phenomenons noticed by the experimentators. The model shows that the transfer factor at equilibrium depends on the experimental conditions and this factor does not allow an absolute quantification of the radiocontamination phenomenon. (Author)

Applicazione delle linee guida nazionali nell'attivitá di notifica di casi di legionellosi

Directory of Open Access Journals (Sweden)

E. Corsano

2003-05-01

Full Text Available

Obiettivi: é noto che effettuare diagnosi di Legionellosi risulta difficile a causa della sovrapposizione della sintomatologia con altre forme di polmonite. Questo spiega, in parte, perché i casi di Legionellosi siano sottostimati. I metodi diagnostici disponibili, sebbene richiedano tempi relativamente lunghi, sono necessari per l’esatta stima di prevalenza della Legionellosi e per gli eventuali interventi preventivi.

Metodi: nell’Azienda Ospedaliera “G. Panico” di Tricase, seguendo i criteri delle Linee Guida della Legionellosi (G.U. 5 maggio 2000 n. 103 durante la degenza dei pazienti che presentavano segni clinici ed obiettivi di polmonite sono state eseguite indagini radiologiche (Rx Torace, TAC, esami di laboratorio (espettorato, sangue, urina ed avviata terapia antibiotica (macrolidi e cefalosporine di III generazione. L’antigene urinario e le IgG anti-Legionella (metodo IFA, sono stati determinati in collaborazione con il Laboratorio di riferimento Regionale.

Risultati: nel periodo ottobre 2001 gennaio 2003 sono stati notificati nel nostro ospedale 11 casi di Legionellosi accertati da indagini clinico-strumentali e di laboratorio: tutti i casi avevano titoli anticorpali abbastanza elevati, confermati poi da un secondo controllo a distanza di tempo. Solo due hanno presentato una positività per l’antigene urinario. All’atto della dimissione, per il 63.6% dei casi è stato documentato un miglioramento delle condizioni clinico-laboratoristico-strumentali, nel 18.2% si è avuta una effettiva guarigione. La letalità è stata pari al 18.2%. In tutti casi si è provveduto alla sorveglianza ambientale.

Considerazioni: i nostri dati evidenziano che i casi di Legionellosi registrati sono stati tutti di tipo comunitario. Una corretta applicazione delle Linee Guida nel sistema di notifica permette l’avvio dell’attività di prevenzione oltre

Optimization of the synthesis of SAPO-11 for the methylation of naphthalene with methanol by varying templates and template content

Energy Technology Data Exchange (ETDEWEB)

Wang, Xiaoxiao [University of Chinese Academy of Sciences, Beijing (China); Zhang, Wei; Zhao, Liangfu; Xiang, Hongwei, E-mail: zw7234@sxicc.ac.cn, E-mail: lfzhao@sxicc.ac.cn [Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan (China); Guo, Shaoqing [Taiyuan University of Science and Technology, Taiyuan (China)

2013-07-15

SAPO-11 zeolites were successfully synthesized by using three different templates (diethylamine (DEA), di-n-propylamine (DPA) and di-isopropylamine (DIPA)) and varying DPA contents (nDPA/Al{sub 2}O{sub 3} = 0.8, 1.2, 1.6 and 2.0) under hydrothermal conditions. The samples were characterized by powder X-ray diffractometry (XRD), scanning electron microscopy (SEM), N{sub 2} adsorption-desorption, temperature programmed desorption of ammonia (NH{sub 3} -TPD) and {sup 29}Si magic angle spinning (MAS) nuclear magnetic resonance (NMR). The samples were also evaluated towards the methylation of naphthalene with methanol to produce 2,6-dimethylnaphthalene (2,6-DMN). XRD results indicated that the directing effect of the different templates for AEL (Aluminophosphate-ELeven) structure decreased in the order DPA > DEA > DIPA and the most suitable DPA content was nDPA/Al{sub 2}O{sub 3} = 1.2. N{sub 2} adsorption-desorption results showed that SAPO-11(DPA,1.2) exhibited the broadest pore size distribution, the highest BET specific surface area and the largest pore volume among all the SAPO-11 samples. SAPO-11(DPA,1.2) exhibited high catalytic performances in the methylation of naphthalene due to its high crystallinity, high external surface and broad pore size distribution. The pore structure of SAPO-11 zeolite, rather than its acidity, played an important role in achieving high catalytic performances in the methylation of naphthalene with methanol. (author)

Waste-to-methanol: Process and economics assessment.

Science.gov (United States)

Iaquaniello, Gaetano; Centi, Gabriele; Salladini, Annarita; Palo, Emma; Perathoner, Siglinda; Spadaccini, Luca

2017-11-01

The waste-to-methanol (WtM) process and related economics are assessed to evidence that WtM is a valuable solution both from economic, strategic and environmental perspectives. Bio-methanol from Refuse-derived-fuels (RdF) has an estimated cost of production of about 110€/t for a new WtM 300t/d plant. With respect to waste-to-energy (WtE) approach, this solution allows various advantages. In considering the average market cost of methanol and the premium as biofuel, the WtM approach results in a ROI (Return of Investment) of about 29%, e.g. a payback time of about 4years. In a hybrid scheme of integration with an existing methanol plant from natural gas, the cost of production becomes a profit even without considering the cap for bio-methanol production. The WtM process allows to produce methanol with about 40% and 30-35% reduction in greenhouse gas emissions with respect to methanol production from fossil fuels and bio-resources, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

Simulation of pressurized water reactor in accidental state

International Nuclear Information System (INIS)

Chakir, E.

1994-01-01

The aim of this work is to develop the 1300 MWe 4 loops 'PWR' simulator called 'SATRAPE', witch the adopted physics modelisation allows a simplified neutronic calculation, and focus essentially on the reactor thermal hydraulic behavior in the case of the following accidents: - Loss of Coolant Accident (LOCA). - Steam Generator Tube Failure (SGTF). - Steam Line Break (SLB). In case of the 'LOCA' or 'SLB' accident, this modelisation enables the calculation of the pressure and the temperature in the containment building, and also the debit of the released dose in this latter in case of the 'LOCA' accident. The adopted models are relatively simple so as to allow an explicit resolve. In SATRAPE, two graphical interfaces enables to launch orders, whereas the other permits to visualize, the principal state variables of installations. The results obtained show a very good consistency with the envisaged commonly scenario at the time of the considered accidents. 33 refs., 52 figs., 1 tab. (author)

Production of methanol/DME from biomass

Energy Technology Data Exchange (ETDEWEB)

Ahrenfeldt, J.; Birk Henriksen, U.; Muenster-Swendsen, J.; Fink, A.; Roengaard Clausen, L.; Munkholt Christensen, J.; Qin, K.; Lin, W.; Arendt Jensen, P.; Degn Jensen, A.

2011-07-01

In this project the production of DME/methanol from biomass has been investigated. Production of DME/methanol from biomass requires the use of a gasifier to transform the solid fuel to a synthesis gas (syngas) - this syngas can then be catalytically converted to DME/methanol. Two different gasifier types have been investigated in this project: 1) The Two-Stage Gasifier (Viking Gasifier), designed to produce a very clean gas to be used in a gas engine, has been connected to a lab-scale methanol plant, to prove that the gas from the gasifier could be used for methanol production with a minimum of gas cleaning. This was proved by experiments. Thermodynamic computer models of DME and methanol plants based on using the Two-Stage Gasification concept were created to show the potential of such plants. The models showed that the potential biomass to DME/methanol + net electricity energy efficiency was 51-58% (LHV). By using waste heat from the plants for district heating, the total energy efficiencies could reach 87-88% (LHV). 2) A lab-scale electrically heated entrained flow gasifier has been used to gasify wood and straw. Entrained flow gasifiers are today the preferred gasifier type for commercial coal gasification, but little information exists on using these types of gasifiers for biomass gasification. The experiments performed provided quantitative data on product and gas composition as a function of operation conditions. Biomass can be gasified with less oxygen consumption compared to coal. The organic fraction of the biomass that is not converted to gas appears as soot. Thermodynamic computer models of DME and methanol plants based on using entrained flow gasification were created to show the potential of such plants. These models showed that the potential torrefied biomass to DME/methanol + net electricity energy efficiency was 65-71% (LHV). Different routes to produce liquid transport fuels from biomass are possible. They include production of RME (rapeseed oil

The biological quality of Sieve downriver the Sabatta waster water plant; La qualita biologica del fiume Sieve a valle del depuratore di Rabatta

Energy Technology Data Exchange (ETDEWEB)

Banchetti, Rosalba; Gasperini, Federico; Bicocchi, Allegra; Cecchini, Agnese; Nolan, Brigitte; Stramaccia, Tania [Pisa Univ., Pisa (Italy). Dipartimento di etologia, ecologia ed evoluzione

2005-10-15

An evaluation study of the environmental condition of Sieve river, based on the Extended Biotic Index method (E.B.I.) applied to macro invertebrates was carried out in 2003. Three sampling locations were selected upriver and downriver a depuration plant and upriver of the confluence of a tributary that flow into the Sieve, the Ensa. The monitoring, carried out in two separate campaigns, in winter and spring, revealed how efficient is the sludge-active plant in determining a good quality of the water. Moreover Bilancino reservoir, with constant discharges, keeps Sieve river flow with a constant regime all through the year, avoiding the summer dry-up of the river and allowing the settlement of a biodiversified macrobenthonic community. [Italian] Nal 2003 e stato condotto uno studio di valutazione dello stato ecologico del fiume Sieve sulla base della comunita di macroinvertebrati, usando il metodo dell'I.B.E. (Indice Biotico Esteso). Sono stati scelti tre punti di campionamento a monte e a valle dello scarico di un impianto di depurazione, in funzione dal 1998, che tratta reflui di origine civile. Il monitoraggio eseguito ha rivelato l'utilita dell'impianto a fanghi attivi nel determinare un netto miglioramento della qualita delle acque.

Investigations into low pressure methanol synthesis

DEFF Research Database (Denmark)

Sharafutdinov, Irek

The central topic of this work has been synthesis, characterization and optimization of novel Ni-Ga based catalysts for hydrogenation of CO2 to methanol. The overall goal was to search for materials that could be used as a low temperature (and low pressure) methanol synthesis catalyst....... This is required for small scale delocalized methanol production sites, where installation of energy demanding compression units should be avoided. The work was triggered by DFT calculations, which showed that certain bimetallic systems are active towards methanol synthesis from CO2 and H2 at ambient pressure...... containing 5:3 molar ratio of Ni:Ga, the intrinsic activity (methanol production rate per active surface area) is comparable to that of highly optimised Cu/ZnO/Al2O3. Formation of the catalyst was investigated with the aid of in-situ XRD and in-situ XAS techniques. The mechanism of alloying was proposed...

Covalent-ionically cross-linked polyetheretherketone proton exchange membrane for direct methanol fuel cell

CSIR Research Space (South Africa)

Luo, H

2010-08-01

Full Text Available cross-linked PEEK-WC membrane, this covalent-ionically cross-linked PEEK-WC membrane exhibits extremely reduced water uptake and methanol permeability, but just slightly sacrificed proton conductivity. The proton conductivity of the covalent...

The fate of methanol in anaerobic bioreactors

NARCIS (Netherlands)

Florencio, L.

1994-01-01

Methanol is an important component of certain industrial wastewaters. In anaerobic environments, methanol can be utilized by methanogens and acetogens. In wastewater treatment plants, the conversion of methanol into methane is preferred because this conversion is responsible for chemical

DAMPAK INVASIF IKAN RED DEVIL (Amphilophus citrinellus TERHADAP KEANEKARAGAMAN IKAN DI PERAIRAN UMUM DARATAN DI INDONESIA

Directory of Open Access Journals (Sweden)

Chairulwan Umar

2015-05-01

Full Text Available Keanekaragaman ikan air tawar di Indonesia sekarang menghadapi ancaman dari berbagai aktivitas manusia yang bisa menyebabkan punahnya ikan-ikan endemik, dan diperkirakan sekitar 87 jenis ikan Indonesia terancam punah. Beberapa faktor yang menjadi ancaman terhadap keanekaragaman ikan dan menimbulkan kepunahan diantaranya introduksi spesies. Perkembangan beberapa spesies ikan menjadi tak terkendali sehingga menjadi hama dan merugikan manusia. Salah satu di antaranya adalah masuknya ikan ‘Red Devil’ ke beberapa perairan umum daratan di Indonesia. Beberapa perairan yang terdapat ikan red devil, mengalami penurunan sumber daya ikan baik jenis maupun jumlah, bahkan beberapa jenis ikan asli banyak yang hilang. Makalah ini bertujuan untuk mengkaji dampak keberadaan ikan ini terhadap keanekaragaman sumberdaya ikan di perairan. Kajian ini bersifat desk study dan pengamatan langsung di lapangan. Verifikasi lapang dilakukan pada tahun 2011 dan 2012. Hasil tangkapan ikan red devil di beberapa perairan waduk dan danau di Indonesia sangat dominan bisa mencapai 40 – 60 %. Dampak dari invasi ikan ini antara lain adalah terjadinya perubahan ekosistem, yaitu penurunan keanekaragaman hayati, dan dampak terhadap kerugian ekonomi seperti biaya untuk mengendalikan jenis ikan asing dan penurunan produksi ikan ekonomis.   Freshwater fish diversity in Indonesia is now facing threats from human activities that could lead to the extinction of endemic fish, and an estimated 87 Indonesian fish species threatened with extinction. Some factors that caused a threat to the diversity and extinction of fish is the introduction of new species. The development of some species of fish become uncontrollable and those being predators and caused a damage for humans life. One of them is the inclusion of Red devil fish to some inland waters in Indonesia. Some inland water that contains of red devil fish caused declining of fish resources in type or amount and

Structure, stabilité et fluctuations

CERN Document Server

Glansdorff, P

1971-01-01

Théorie générale : lois de conservation et bilans ; le second principe de la thermodynamique et le bilan entropique ; thermodynamique linéaire des phénomènes irréversibles ; théorie de la stabilité de l'équilibre thermodynamique par la méthode Gibbs-Duhem ; théorie générale de la stabilité de l'équilibre thermodynamique ; conditions de stabilité thermodynamique et hydrodynamique des syst¿mes hors d'équilibre ; forme explicite des conditions de stablité des processus hors d'équilibre ; stabilité et fluctuations ; le critère général d'évolution.

Engineering Escherichia coli for methanol conversion.

Science.gov (United States)

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. Copyright © 2015 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

Methods of conditioning direct methanol fuel cells

Science.gov (United States)

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.

Novel electrode structure for DMFC operated with liquid methanol

International Nuclear Information System (INIS)

Shao, Z.-G.; Lin, W.; Christensen, P.A.; Zhu, F.; Slowinski, G.; Amini, M.K.; Scott, K.

2004-01-01

'Full text:' Up to now, the electrodes for direct methanol fuel cell (DMFC) were developed mostly on the basis of the gas diffusion electrodes employed in proton exchange membrane fuel cells. Typically, the structure of such electrodes comprises a catalyst layer and a diffusion layer, the latter being carbon cloth or carbon paper. However, unlike other fuel cells, the liquid feed DMFC suffers from mass transport limitations predominantly at the anode due to the low diffusion coefficient of methanol in water. In addition, carbon paper is fragile and expensive and carbon cloth is soft compared with metal material, such materials are not as versatile as metals. In our present work, new structures of the anode and cathode have been developed. The preparation procedures and the main characteristics of the anodes and cathodes have been studied and will be reported. (author)

Novel proton exchange membrane based on crosslinked poly(vinyl alcohol) for direct methanol fuel cells

Science.gov (United States)

Liu, Chien-Pan; Dai, Chi-An; Chao, Chi-Yang; Chang, Shoou-Jinn

2014-03-01

In this study, we report the synthesis and the characterization of poly (vinyl alcohol) based proton conducting membranes. In particular, we describe a novel physically and chemically PVA/HFA (poly (vinyl alcohol)/hexafluoroglutaric acid) blending membranes with BASANa (Benzenesulfonic acid sodium salt) and GA (Glutaraldehyde) as binary reaction agents. The key PEM parameters such as ion exchange capacity (IEC), water uptake, proton conductivity, and methanol permeability were controlled by adjusting the chemical composition of the membranes. The IEC value of the membrane is found to be an important parameter in affecting water uptake, conductivity as well as the permeability of the resulting membrane. Plots of the water uptake, conductivity, and methanol permeability vs. IEC of the membranes show a distinct change in the slope of their curves at roughly the same IEC value which suggests a transition of structural changes in the network. The proton conductivities and the methanol permeability of all the membranes are in the range of 10-3-10-2 S cm-1 and 10-8-10-7 cm2 s-1, respectively, depending on its binary crosslinking density, and it shows great selectivity compared with those of Nafion®-117. The membranes display good mechanical properties which suggest a good lifetime usage of the membranes applied in DMFCs.

Direct methanol feed fuel cell with reduced catalyst loading

Science.gov (United States)

Kindler, Andrew (Inventor)

1999-01-01

Improvements to direct feed methanol fuel cells include new protocols for component formation. Catalyst-water repellent material is applied in formation of electrodes and sintered before application of ionomer. A membrane used in formation of an electrode assembly is specially pre-treated to improve bonding between catalyst and membrane. The improved electrode and the pre-treated membrane are assembled into a membrane electrode assembly.

Elementi di interfaccia per l’analisi di strutture murarie

Directory of Open Access Journals (Sweden)

Jessica Toti

2009-04-01

Full Text Available Il presente articolo riguarda la modellazione del comportamento meccanico di elementi in muratura intesi come sistemi eterogenei composti da malta, blocchi ed interfacce di connessione. La strategiacomputazionale che viene adottata consiste nel modellare separatamente i blocchi, i letti di malta ed le interfacce responsabili di fenomeni di decoesione malta-blocco; a tale scopo, si propone uno speciale modello di interfaccia che combina il danneggiamento con l’attrito. Si sviluppa una procedura numerica, basata sull’algoritmo backward di Eulero, per risolvere il problema evolutivo; per il passo temporale si utilizza invece la tecnica predictor-corrector a controllo di spostamenti. Si effettuano alcune applicazioni numeriche con lo scopodi verificare la capacità del modello e dell’algoritmo proposto nel riprodurre la risposta non lineare della muratura dovuta a fenomeni di degrado localizzati. Infine, si conduce lo studio della modellazione di un arco murario, confrontando i risultati numerici con quelli sperimentali; si dimostra la abilità del modello proposto nel simulare il comportamento globale della struttura ad arco in termini di carico ultimo e di meccanismo di collasso.

Thermodynamic functions of hydrogen bonding of amines in methanol derived from solution calorimetry data and headspace analysis

International Nuclear Information System (INIS)

Zaitseva, Ksenia V.; Varfolomeev, Mikhail A.; Solomonov, Boris N.

2012-01-01

Highlights: ► Solution enthalpies and activity coefficients of amines in methanol were measured. ► Thermodynamic functions of H-bonding of amines with methanol were determined. ► Specific interaction entropy of amines in methanol can be about zero or positive. ► Cooperativity of H-bonds in methanol media is smaller than in water solutions. ► A new view on analysis of specific interaction of solute with methanol is presented. - Abstract: Reactivity and equilibrium properties of organic molecules in self-associated liquids greatly depend on the hydrogen bonding with solvent. This work contains comprehensive thermodynamic analysis of hydrogen bonding of aliphatic and aromatic amines in self-associated solvent methanol. Enthalpies of solution at infinite dilution and limiting activity coefficients for the studied systems were measured experimentally. Enthalpies and Gibbs energies of hydrogen bonding of amines with neat methanol were determined. These values were found to be decreased compared with hydrogen bond energy in equimolar complexes “methanol–amine” determined in inert solvent or base media. A linear dependence between enthalpies and Gibbs energies of hydrogen bonding of amines with neat methanol was observed. It was firstly revealed that the entropy of specific interactions of amines with neat methanol can be about zero or positive. Disruption of solvent–solvent hydrogen bonds can be regarded as the most important step during dissolution of amine in methanol. It was found that the cooperative effect influences on the Gibbs energies of hydrogen bonding of amines in methanol, but in a lesser extent than in aqueous solutions. The new results show that the hydrogen bonding process in the self-associated solvents differs significantly from equimolar complexation in aprotic media.