ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Methane
  • Springer  (33)
  • American Physical Society
  • Annual Reviews
  • Blackwell Publishing Ltd
  • 2005-2009  (2)
  • 1990-1994  (27)
  • 1980-1984  (4)
  • 1
    ISSN: 1572-879X
    Keywords: Methane ; oxidative coupling ; catalyst ; reactor configuration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Introduction of additional O2 at the midpoint of the catalyst bed of a methane oxidative coupling, fixed bed reactor, increases the C2 STY more than the CO x . STY over a Li/Pb/Ca catalyst. This observation is not only a consequence of kinetics but may also be attributed to increased methyl radical generation on the O2 replenished catalyst surface.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Catalysis letters 16 (1992), S. 263-268 
    ISSN: 1572-879X
    Keywords: Methane ; partial oxidation ; additive ; natural gas ; ZSM-5
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Previously, it was reported that the direct partial oxidation (DPO) of CH4 with O2 over HZSM-5 catalysts produces C5+ hydrocarbon liquids when the feed contains a propane or propene additive. This work studies additive effects on C5+ production in this system by processing a CH4/C3H8 feed with subsequent removal of the C3 additive and by processing natural gas feed. Results show C5+ production is maintained at constant yields for HZSM-5 catalysts having different zeolitic Al contents after removal of the C3 additive. Mechanistic implications are discussed. Natural gas DPO consistently produced C5+ liquids due to the presence of C2+ components in the feed. While C5+ yields from natural gas DPO are higher than those observed for CH4/C3 feeds, increasing feed O2 concentration, and thus conversion, deleteriously affected C5+ selectivity.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1572-879X
    Keywords: Methane ; oxidative coupling ; lamellar perovskites ; Aurivillius phases
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The oxidative coupling of methane has been studied in the presence of lamellar perovskites Bi2O2(An-1BnO3n+1) belonging to Aurivillius phases. These materials are selective and stable in the OCM reaction. Moreover, their substitution in perovskite (A) or octahedral (B) sites leads to significant changes of the C2+ selectivity or yield which are attributed to modifications of the basicity of A-O or B-O bonds.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Catalysis letters 13 (1992), S. 143-152 
    ISSN: 1572-879X
    Keywords: Methane ; conversion ; oxidative dehydrogenation ; cations ; sulphates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The oxidative coupling of methane has been studied on Mg, Ca, Sr and Ba sulphate. The conversions and selectivities are found to be dependent on the nature of the cation and to be approximately correlated with their electronegativities, thus implying that the C-H bond scission in CH4, at least with these catalysts, is heterolytic, is rate determining, and further, that the formation of C2+ hydrocarbons is dependent, among other factors, on the concentration of methyl radicals.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Catalysis letters 13 (1992), S. 341-347 
    ISSN: 1572-879X
    Keywords: Methane ; oxidation ; oxidative coupling ; hydroformylation ; propanal ; catalysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract High yield synthesis of propanal from methane and air can be obtained in a single pass at atmospheric pressure. Three catalytic processes are combined to give 13% yield of propanal based on total methane input. Ethene is made from the oxidative coupling reaction and carbon monoxide and hydrogen is generated from partial oxygenation of methane. These gases are combined and passed to a hydroformylation catalyst to give liquid propanal. The unreacted methane is inert in the hydroformylation stage, while oxygen deactivates the catalyst readily. The results imply that propanal can be obtained, in good yield, from methane and air provided that total oxygen conversion is achieved. The yield of propanal from the three combined processes can be substantially higher than that of ethene from the oxidative coupling reaction. Thus, higher yields of a condensible and oxygenated product are obtained.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1572-879X
    Keywords: Methane ; oxidation coupling ; formaldehyde ; strontium/lanthanum oxide ; hydrocarbons
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract A double layered catalyst bed of Sr/La2O3 followed by MoO3/SiO2 has been used to produce C2 hydrocarbons and formaldehyde from a CH4/air mixture with a formaldehyde space time yield of 187 g (kg cat)−1 h−1, which is significantly higher than those yields obtained with single bed catalysts or with mechanically mixed catalyst bed at ambient pressure and 630 ° C.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Catalysis letters 17 (1993), S. 197-204 
    ISSN: 1572-879X
    Keywords: Methane ; conversion ; oxidative dehydrogenation ; oxidative coupling ; hydroxyapatite
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Hydroxyapatite modified with lead catalyzes the oxidative dehydrogenation of methane with high selectivity to C2 compounds at reaction temperatures as low as 700 °C. The activity is stabilized after reduction in the surface area of the catalyst during the reaction.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Catalysis letters 18 (1993), S. 27-35 
    ISSN: 1572-879X
    Keywords: Methane ; oxidative coupling ; bialkali promoted magnesia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Upon promoting MgO (prepared via a sol-gel process) with any binary mixture of the alkali metal chlorides, catalytic systems are obtained which are more active, selective and much more stable with time-on-stream than the respective monoalkali promoted MgO in the oxidative coupling of methane (OCM) to C2 hydrocarbons. The best catalytic performance is obtained over (5 mol% NaCl+5 mol% CsCl)/MgO, which exhibits a C2 yield of 19.7% compared to 5.9 and 4.1% over 10 mol% NaCl/MgO and 10 mol% CsCl/MgO, respectively, at atmospheric pressure, a temperature of 750 °C, a space velocity of 15000 cm3 g−1 h−1, $$P_{CH_4 }$$ = 608 Torr and CH4/O2 = 4. A series of different combinations among the five alkali chlorides were made and the afore-mentioned synergistic effect was always observed. The basicity and base strength distribution of the bialkali chloride systems (measured by the gaseous acid adsorption or benzoic acid titration methods) are significantly higher than those of the respective monoalkali halide systems. The relationship between the catalytic performance and basicity/base strength distribution is explored.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1572-879X
    Keywords: Methane ; formaldehyde ; oxidation ; vanadium oxide ; silica
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Methane oxidation to formaldehyde was studied over a vanadium oxide catalyst supported on silica at 630 °C using the technique known as temporal analysis of products with sequential pulsing of methane and oxygen. This work shows that methane interacts very weakly and oxygen very strongly with the catalyst surface and it is concluded that the initial activation of methane involves an adsorbed oxygen species. Methyl radicals formed in the first step subsequently extract lattice oxygen to yield formaldehyde.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Catalysis letters 24 (1994), S. 85-94 
    ISSN: 1572-879X
    Keywords: Methane ; partial oxidation ; nitrous oxide ; iron molybdate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The product distributions for partial oxidation of methane on Fe2(MoO4)3 catalyst were changed remarkably when the oxidant was switched from oxygen to nitrous oxide. When oxygen was used as the oxidant, the main products were HCHO and CO. However, when nitrous oxide was used, the formation of HCHO was greatly suppressed and C2 hydrocarbons (C2H6 and C2H4) were newly produced. The difference in kinetic behaviors between the two reactions using nitrous oxide and oxygen as the oxidant can be explained in terms of the competitive conversions of methyl intermediate into HCHO and C2H6. In the case of nitrous oxide as the oxidant, the adsorbed methyl intermediate would be transformed predominantly into C2H6 due to a low steady-state concentration of the active oxygen species on Fe2(MoO4)3.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Catalysis letters 16 (1992), S. 27-38 
    ISSN: 1572-879X
    Keywords: Methane ; chlorination ; solid acid ; zeolites
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Chlorination of methane was studied over amorphous silica-alumina, silicalite as well as H-mordenite, X, Y, NaL and H-ZSM-5 zeolite catalysts. The heterogeneous transformations were carried out in a continuous flow reactor in the 200–425 °C temperature range, under atmospheric pressure (methane to chlorine ratio 4:1, GHSV 600 ml/ g h). Chlorination of methane over zeolites in the 200–300 °C temperature range proceeds without selectivity indicating a radical mechanism. Above 300–350 °C, depending on the nature of zeolite, selective monochlorination takes place indicating the dominance of an ionic mechanism. H-mordenite was found to give the best monochlorination at the lowest temperature (99.2% CH3Cl at 350 °C). The observed selectivity of the investigated zeolites is strongly time limited. All investigated catalysts lose their selectivity after five hours on-stream due to extraction of aluminum from the framework of zeolites by hydrogen chloride. Amorphous silica-alumina above 350 °C also catalyzes ionic chlorination. The chlorination of methane over silicalite proceeds via the nonselective radical pathway at the investigated temperatures.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    Electronic Resource
    Electronic Resource
    Springer
    Catalysis letters 16 (1992), S. 251-261 
    ISSN: 1572-879X
    Keywords: Methane ; formaldehyde ; silica ; Cabosil ; coupling catalyst
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Partial oxidation of methane by oxygen to form formaldehyde, carbon oxides, and C2 products (ethane and ethene) has been studied over silica catalyst supports (fumed Cabosil and Grace 636 silica gel) in the 630–780 °C temperature range under ambient pressure. The silica catalysts exhibit high space time yields (at low conversions) for methane partial oxidation to formaldehyde, and the C2 hydrocarbons were found to be parallel products with formaldehyde. Short residence times enhanced both the C2 hydrocarbons and formaldehyde selectivities over the carbon oxides even within the differential reactor regime at 780 °C. This suggests that the formaldehyde did not originate from methyl radicals, but rather from methoxy complexes formed upon the direct chemisorption of methane at the silica surface at high temperature. Very high formaldehyde space time yields (e.g., 812 g/kg cat h at the gas hourly space velocity = 560 000 ℓ(NTP)/kg cat h) could be obtained over the silica gel catalyst at 780 °C with a methane/air mixture of 1.5/1. These yields greatly surpass those reported for silicas earlier, as well as those over many other catalysts. Low CO2 yields were observed under these reaction conditions, and the selectivities to formaldehyde and C2 hydrocarbons were 28.0 and 38.8%, respectively, at a methane conversion of 0.7%. A reaction mechanism was proposed for the methane activation over the silica surface based on the present studies, which can explain the product distribution patterns (specifically the parallel formation of formaldehyde and C2 hydrocarbons).
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    Electronic Resource
    Electronic Resource
    Springer
    Catalysis letters 16 (1992), S. 269-272 
    ISSN: 1572-879X
    Keywords: Methane ; carbon monoxide ; hydrogen ; synthesis gas ; Co/rare earth oxide catalysts ; oxidation of methane to CO and H2
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract CoO-rare earth oxide catalysts (particularly CoO-Yb2O3) show high activity and selectivity in the oxidative conversion of methane to CO and H2 with very high productivity at low temperatures (⩽ 700 °C as low as 300 °C).
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    Electronic Resource
    Electronic Resource
    Springer
    Catalysis letters 16 (1992), S. 389-398 
    ISSN: 1572-879X
    Keywords: Methane ; oxidative dehydrogenation ; zirconium oxide ; hydroxyl ; steaming
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Zirconium oxide is shown to be capable of catalyzing the conversion of methane to ethane at temperatures as low as 530 °C. The lowest temperature at which ethane is produced is found to be dependent upon the method employed for the preparation of the catalyst. The presence of surface hydroxyl groups appears to be necessary for the production of ethane at these low temperatures.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    ISSN: 1572-879X
    Keywords: Methane ; formaldehyde ; molybdenum oxide ; silica ; Raman spectroscopy ; TPR ; XPS
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The effect of the nature of surface species on the activity and selectivity of MoO3/SiO2 catalysts has been investigated for the partial oxidation of methane to formaldehyde. Characterization techniques including BET surface area, ambient and in situ Raman spectroscopy, X-ray photoelectron spectroscopy, and temperature-programmed reduction were used in conjunction with steady-state reaction studies to relate the presence of different surface species to the activity and selectivity of the catalyst. Results of these experiments indicate the presence of a highly dispersed silicomolybdic species with terminal Mo=O sites appearing at lower MoO3 loadings. As the weight loading increases, these sites are transformed into polymolybdate species, forming more Mo-O-Mo bridging sites at the expense of Mo=O sites. At high weight loadings, crystalline MoO3 begins to form. The abundance of the Mo=O sites is believed to affect activity and selectivity in the partial oxidation of methane to formaldehyde.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    Electronic Resource
    Electronic Resource
    Springer
    Catalysis letters 25 (1994), S. 11-19 
    ISSN: 1572-879X
    Keywords: Methane ; chlorination ; solid superacids ; sulfated zirconia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Catalytic chlorination of methane was studied over SO 4 2− /ZrO2, Pt/SO 4 2− /ZrO2, and Fe/Mn/SO 4 2− /ZrO2 solid superacid catalysts. The reactions were carried out in a continuous flow reactor under atmospheric pressure, at temperatures below 240°C, with a gaseous hourly space velocity of 1000 ml/g h and a methane to chlorine ratio of 4 to 1. At 200°C with 30% chlorine converted the selectivity in methyl chloride exceeds 90%. At more elevated temperatures, the selectivity decreases but stays above 80% in methyl chloride at 225°C using the sulfated zirconia catalysts. The selectivity can be enhanced by adding platinum to sulfated zirconia catalysts. An iron and manganese-doped catalyst exhibited excellent selectivities at somewhat lower conversions. Methyl chloride is obtained at 235°C in selectivities greater than 85%. No chloroform or carbon tetrachloride is formed. The electrophilic insertion involves electron-deficient metal-coordinated chlorine into the methane C-H bond.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    Electronic Resource
    Electronic Resource
    Springer
    Catalysis letters 4 (1990), S. 241-244 
    ISSN: 1572-879X
    Keywords: Methane ; oxidative coupling ; oxide ; MgO ; CaO
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Mixed oxide catalyst prepared by co-precipitating magnesium oxide and calcium oxide showed an excellent activity for the oxidative coupling of methane. The high performances were presumed to arise from the high basicity of the mixed oxide.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    Electronic Resource
    Electronic Resource
    Springer
    Journal of solution chemistry 9 (1980), S. 141-161 
    ISSN: 1572-8927
    Keywords: Methane ; gas solubility ; Ostwald coefficients ; water ; triethylenediamine ; thermodynamic quantities ; hydrophobic interaction ; London dispersion forces ; tetraalkylammonium ions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The solubilities of methane were measured in water and aqueous solutions of triethylenediamine (TED), triethylenediamine hydrochloride (TED·HCl), and HCl at several concentrations up to 1M at 5° intervals from 5 to 25°C. Methane solubilities in solutions of TED·HCl and HCl are lower than those in water and decrease with increasing cosolute concentration. In contrast, the solubilities in TED solutions are greater than those in water and increase with increasing TED concentration. The order of methane solubilities at 25°C in water and in 0.5M aqueous solutions is TED〉H2O〉HCl〉TED·HCl with Ostwald coefficients of 3.57×10−2, 3.44×10−2, 3.26×10−2, and 3.19×10−2, respectively, and with an experimental precision of about ±0.2×10−3. Thermodynamic functions for the transfer of methane from water to 0.25, 0.50, and 0.75M aqueous solutions have been calculated on the molar concentration scale. The free energies of transfer are compared with previous results for methane in aqueous solutions of tetraalkylammonium halides.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    Electronic Resource
    Electronic Resource
    Springer
    Catalysis letters 9 (1991), S. 23-34 
    ISSN: 1572-879X
    Keywords: Methane ; phosphates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The oxidative coupling of methane has been tested over alkali- and alkaline earth-phosphate catalysts at 700 and 775 °C with and without the introduction of a small quantity of tetrachloromethane (TCM) to the feedstream. In general, the conversion of methane was enhanced by the addition of TCM but the effect on selectivity was dependent on the catalyst being examined. The selectivity to C2 and higher hydrocarbons and that to oxidation products have been shown to have a dependence on the cation radius/charge ratio.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    Electronic Resource
    Electronic Resource
    Springer
    Catalysis letters 16 (1992), S. 217-221 
    ISSN: 1572-879X
    Keywords: Methane ; ethane ; methanol ; ethanol ; ozone ; oxygen atom ; oxidation ; sensitization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The reaction of O2, O3, and CH4 or C2H6 of 7.76, 0.24 and 92% of the hydrocarbon respectively (residence time of 8.8 min) at 1 atm, and 400 °C for CH4 and 300 °C for C2H6 gave CO, CO2, H2O, CH2O and CH3OH from CH4 and in addition CH4, C2H4, CH3CHO and C2H5OH from C2H6. No reaction occurred when O3 was absent indicating that the partial oxidation was sensitized (initiated) by the oxygen atoms formed by the decomposition of ozone.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    Electronic Resource
    Electronic Resource
    Springer
    Nutrient cycling in agroecosystems 37 (1994), S. 213-225 
    ISSN: 1573-0867
    Keywords: Methane ; nitrous oxide ; emission inventories ; climate change ; greenhouse gases
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Methane and nitrous oxide are important greenhouse gases. They contribute to global warming. To a large extent, emissions of methane and nitrous oxide are connected with the intensification of food production. Therefore, feeding a growing world population and at the same time controlling these emissions is a great challenge. Important anthropogenic sources of biogenic methane are wet rice fields, cattle, animal waste, landfills and biomass burning. Important anthropogenic sources of biogenic nitrous oxide are land-use change, fertilizer production and use and manure application. The ultimate objective of the Framework Convention on Climate Change implies a stabilization of greenhouse gas concentrations in the atmosphere. As a small first step towards achieving this objective, the Convention requires the industrialized countries to bring their anthropogenic emissions of greenhouse gases by 2000 back to 1990 levels. It was also agreed that all parties would make national inventories of anthropogenic greenhouse gas emissions and programmes for control (UN, 1992). In this context, in February 1993 an international workshop was held in Amersfoort in the Netherlands to discuss methods in national emission inventories for methane and nitrous oxide, and options for control (Van Amstel, 1993). A selection of the papers presented in Amersfoort that focus on agricultural sources is published in this volume. This introductory chapter gives background information on biogenic sources and sinks of methane and nitrous oxide and options for their control. The goal of the Climate Convention is described as well as the IPCC effort to develop an internationally accepted methodology for the monitoring of greenhouse gas emissions and sinks. Finally, some preliminary results from country inventories are given. It is concluded that a common reporting framework and transparency of the inventories are important to obtain comparable results that can be used for complying with the requirements of the Climate Convention and for facilitating the international debate about appropriate response strategies.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    Electronic Resource
    Electronic Resource
    Springer
    Oecologia 91 (1992), S. 126-128 
    ISSN: 1432-1939
    Keywords: Methane ; Baldcypress ; Taxodium ; Cypress knees ; Floodplains ; Blackwater
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Methane emissions were observed from knees of baldcypress (Taxodium distichum) in floodplain swamps of the Ogeechee river, a blackwater river in the lower coastal plain of Georgia, USA Emissions were sampled on 10 dates from March 1988 to September 1989, with small chambers placed over single knees. Methane emission rates from individual knees averaged 0.90 mg/d, corresponding to an average of 0.14 mg m−2 d−1 for the whole floodplain. In the habitat with the highest knee density (0.42 knees/m2), the average rate was 0.55 mg m−2 d−1. Spatial patterns in emissions from knees were similar to those of overall methane emissions from the swamp surface, though because of their low density were a minor contribution (0.42%) to total methane emissions from this system.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    Electronic Resource
    Electronic Resource
    Springer
    Environmental management 15 (1991), S. 411-431 
    ISSN: 1432-1009
    Keywords: Landfill gas ; Tree ; Root growth ; Carbon dioxide ; Methane
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract An account is given of the influence of landfill gas on tree growth in the field at Gin Drinkers' Bay (GDB) landfill, Hong Kong, and in the laboratory. Ten species (Acacia confusa, Albizzia lebbek, Aporusa chinensis, Bombax malabaricum, Castanopsis fissa, Liquidambar formosana, Litsea glutinosa, Machilus breviflora, Pinus elliottii, andTristania conferta), belonging to eight families, were transplanted to two sites, one with a high concentration of landfill gas in the cover soil (high-gas site, HGS) and the other with a relatively low concentration of gas (low-gas site, LGS). Apart from the gaseous composition, the general soil properties were similar. A strong negative correlation between tree growth and landfill gas concentration was observed. A laboratory study using the simulated landfill gas to fumigate seedlings of the above species showed that the adventitious root growth ofAporusa chinensis, Bombax malabaricum, Machilus breviflora, andTristania confera was stimulated by the gas, with shallow root systems being induced.Acacia confusa, Albizzia lebbek, andLitsea glutinosa were gas-tolerant, while root growth ofCastanopsis fissa, Liquidambar formosana, andPinus elliottii was inhibited. In most cases, shoot growth was not affected, exceptions beingBombax malabaricum, Liquidambar formosana, andTristania conferta, where stunted growth and/or reduced foliation was observed. A very high CO2 concentration in cover soil limits the depth of the root system. Trees with a shallow root system become very susceptible to water stress. The effects of low O2 concentration in soil are less important than the effects of high CO2 concentration.Acacia confusa, Albizzia lebbek, andTristania conferta are suited for growth on subtropical completed landfills mainly due to their gas tolerance and/or drought tolerance.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    Electronic Resource
    Electronic Resource
    Springer
    Biology and fertility of soils 11 (1991), S. 231-233 
    ISSN: 1432-0789
    Keywords: Nitrification ; Hydrocarbons ; Methane ; Ethane ; Ethylene ; Acetylene ; Nitrosomonas europaea
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Recent work has shown that gaseous hydrocarbons such as methane, ethane, and ethylene are competitive inhibitors of the monooxygenase enzyme responsible for oxidation of ammonia by chemoautotrophic nitrifying microorganisms such as Nitrosomonas europaea. Because methane, ethane, and ethylene are produced by microbial activity in soil, we studied the possibility that they may inhibit oxidation of ammonia by the nitrifying soil microorganisms. We found that all three of these gaseous hydrocarbons inhibited nitrification in soil and that their ability to inhibit nitrification decreased in the order: ethylene 〉 ethane 〉 methane. Ethylene was much more effective than ethane or methane for inhibiting nitrification of ammonium in soil, but it was much less effective than acetylene, and it seems unlikely that the amounts of ethylene produced in soils will be sufficient to cause significant inhibition of nitrification by soil microorganisms.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 160 (1993), S. 137-143 
    ISSN: 1432-072X
    Keywords: Anaerobic ; Defluorination ; Fluorobenzoate ; Fluorophenol ; Methane ; Phenol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract 3-Fluorobenzoate and all three isomers of fluorophenol were used as analogues and inhibitors of phenol degradation in a methanogenic consortium. 3-Fluorobenzoate was not transformed by phenol-degrading cultures, but it facilitated the detection of the formation of 4-hydroxybenzoate and benzoate from phenol. The effects of the fluorophenols depended on their concentration in the cultures. When added at 0.90 mM, all fluorophenols prevented phenol transformation. At concentrations of 0.45 to 1.8 mM, 2-fluorophenol was transformed to 3-fluoro-4-hydroxybenzoate which accumulated in the medium. When both 2-fluorophenol and phenol were added to cultures at concentrations of 1 mM each, 3-fluoro-4-hydroxybenzoate, 4-hydroxybenzoate, 3-fluorobenzoate and benzoate were detected. 4-Fluorophenol was never transformed, and when it was present at ≦0.22 mM, it had no effect on phenol degradation. At concentrations ≦0.09 mM, 2-fluorophenol was mineralized by the phenol-degrading cultures to methane, carbon dioxide, and fluoride. The release of fluoride was also observed from 3-fluorophenol when it was initially present at ≦0.09 mM. These results support the proposed pathway for phenol degradation involving an initial para-carboxylation to 4-hydroxybenzoate followed by dehydroxylation to benzoate and further metabolism to carbon dioxide and methane. They also demonstrate defluorination of 2- and 3-fluorophenols under methanogenic conditions.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    Electronic Resource
    Electronic Resource
    Springer
    Archives of microbiology 157 (1992), S. 425-430 
    ISSN: 1432-072X
    Keywords: (Anaerobic degradation) ; C1-Compounds ; Methylated sulfur compounds ; Methane ; Methanogenic bacteria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract From dilution series in defined mineral medium, a marine iregular coccoid methanogenic bacterium (strain MTP4) was isolated that was able to grow on methanethiol as sole source of energy. The strain also grew on dimethylsulfide, mono-, di-, and trimethylamine, methanol and acetate. On formate the organism produced methane without significant growth. Optimal growth on MT, with doubling times of about 20 h, occurred at 30°C in marine medium. The isolate required p-aminobenzoate and a further not identified vitamin. Strain MTP4 had a high tolerance to hydrogen sulfide but was very sensitive to mechanical forces or addition of detergents such as Triton X-100 or sodium dodecylsulfate. Methanethiol was fermented by strain MTP4 according to the following equation: 1 $$\begin{array}{*{20}c} {4CH_3 SH + 3H_2 O \to 3CH_4 + HCO_3^ - } \\ { + 4HS^ - + 5H^ + } \\ {(\Delta G^{{\rm O}{\rm I}} = - 36.9kJ/MT)} \\ \end{array} $$ The growth yield was 3.06 g cell dry mass per mol of MT. During growth on MT the isolate released small amounts of DMS and, vice versa, degradation of DMS was accompanied by significant intermediate MT production.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical chemistry accounts 59 (1981), S. 291-297 
    ISSN: 1432-2234
    Keywords: Tetrahedral lobes ; Methane ; Ethane ; Cusped-Gaussian basis ; Polarization functions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The representation of atomic p orbitals in terms of tetrahedral Gaussian lobe functions is shown to be a viable alternative to more conventional representations in terms of cartesian Gaussians or octahedral lobe functions. Fairly accurate SCF calculations for the methane and ethane molecules show that the flexibility of the tetrahedral representation can be used to introduce a degree of polarization into the atomic basis in a molecular environment. Combined with the use of molecular bond functions, this flexibility provides an economical description of polarization effects in molecules.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    Electronic Resource
    Electronic Resource
    Springer
    Journal of industrial microbiology and biotechnology 13 (1994), S. 147-153 
    ISSN: 1476-5535
    Keywords: Anaerobic ; Biodegradation ; Cellulose ; Landfills ; Municipal solid waste ; Methane
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary Improved techniques are needed to predict potential methane generation from refuse buried in landfills. The Biochemical Methane Potential (BMP) test was used to measure the methane potential of ten refuse samples excavated from a Berkeley, CA, landfill. The test was conducted in 125-ml serum bottles containing phosphate-buffered medium and inoculated with anaerobically digested sewage sludge. Comparison of the measured BMP to the theoretical BMP calculated from measured cellulose and hemicellulose concentrations indicated that cellulose plus hemicellulose is not well correlated with the measured BMP. The average of the measured to theoretical BMP was 19.1% (range 0–53%, s.d.=16.9%). Measured sulfate concentrations showed that sulfate was an insignificant electron sink in the samples tested. Once methane production from the refuse was complete, 0.072 g of Whatman no. 1 filter paper was added to two of the four serum bottles incubated for each sample. An average of 84.9% (s.d=2.5%) of the added filter paper was recovered as methane, suggesting that some cellulose and hemicellulose present in refuse is recalcitrant or otherwise not bioavailable.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    Electronic Resource
    Electronic Resource
    Springer
    Nutrient cycling in agroecosystems 33 (1992), S. 115-121 
    ISSN: 1573-0867
    Keywords: Methane ; NH4NO3 ; (NH4)2SO4 ; organic matter ; rice soil ; soil redox ; urea
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Laboratory experiments were conducted on the effects of rice straw application and N fertilization on methane (CH4) production from a flooded Louisiana, USA, rice soil incubated under anaerobic conditions. Rice straw application significantly increased CH4 production; CH4 production increased in proportion to the application rate. Urea fertilization also enhanced CH4 production. The maximum production rate was 17% higher, and occurred 1 week earlier, than that of soil samples which did not receive urea, possibly due to the increase in soil pH following urea hydrolysis. The increase in soil pH following urea hydrolysis may have stimulated CH4-generating bacteria by providing more optimal soil pH conditions or contributed to the drop in redox potential (Eh). The significant decrease in both the production rate and the total amount of CH4 by application of NH4NO3 was associated with increases in soil Eh after addition of this oxidant. Addition of 300 mg. kg−1 NO 3 - -N increased soil Eh by 220 mV and almost completely inhibited CH4 production. However, this inhibitory effect was short-termed. Soon after the applied NO 3 - -N was reduced through denitrification, CH4 production increased. When (NH4)2SO4 was applied, the inhibition of CH4 production was not associated with an increase in soil Eh which did not change significantly. A direct inhibitory effect of sulphate on methanogenesis might have been more important.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    Electronic Resource
    Electronic Resource
    Springer
    Journal of atmospheric chemistry 1 (1984), S. 125-135 
    ISSN: 1573-0662
    Keywords: Methane ; troposphere ; southern hemisphere ; trend ; annual cycle ; vertical gradient
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract Results of more than 800 new measurements of methane (CH4) concentrations in the Southern Hemisphere troposphere (34–41° S, 130–150° E) are reported. These were obtained between September 1980 and March 1983 from the surface at Cape Grim, Tasmania, through the middle (3.5–5.5 km) to the upper troposphere (7–10 km). The concentration of CH4 increased throughout the entire troposphere over the measurement period, adding further support to the view that CH4 concentrations are currently increasing on a global scale. For data averaged vertically through the troposphere the rate of increase found was 20 ppbv/yr or 1.3%/yr at December 1981. In the surface CH4 data a seasonal cycle with a peak to peak amplitude of approximately 28 ppbv is seen, with the minimum concentration occurring in March and the maximum in September–October. A cycle with the same phase as that seen at the surface, but with a significantly decreased amplitude, is apparent in the mid troposphere but no cycle is detected in the upper tropospheric data. The phase and amplitude of the cycle are qualitatively in agreement with the concept that the major sink for methane is oxidation by hydroxyl radicals. Also presented is evidence of a positive vertical gradient in methane, with a suggestion that the magnitude of this gradient has changed over the period of measurements.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    Electronic Resource
    Electronic Resource
    Springer
    Journal of atmospheric chemistry 1 (1984), S. 171-186 
    ISSN: 1573-0662
    Keywords: Methane ; carbon dioxide ; production ; destruction ; termites ; soils
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract The flux of CH4 and CO2 from termite nests into the atmosphere has been measured in a broad-leafed-type savannah in South Africa. Measurements were carried out on nests of species of six genera, i.e., Hodotermes, Macrotermes, Odontotermes, Trinervitermes, Cubitermes, and Amitermes. The flux rates of CH4 relative to the flux rate of CO2 in terms of carbon obtained for the individual species showed ratios of 2.9×10-3, 7.0×10-4, 6.7×10-5, 8.7×10-3, 2.0×10-3 and 4.2×10-3, respectively. Using data published on the assimulation efficiencies of termites, the flux of carbon as CH4 accounts for 6.0×10-5 to 2.6×10-3 of the carbon ingested which results in a global CH4 emission by termites of 2 to 5×1012 g/yr. Methane is decomposed in the soil with average decomposition rates of 52 μg/m2/h. The annual CH4 consumption in the tropics and subtropics is estimated to be 21×1012 g which exceeds the CH4 emission rate by termites.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    Publication Date: 2022-02-16
    Description: The role of mud volcanoes (MVs) as a source of methane(CH4) flux to the atmosphere and the ocean has been increasingly recognised in the last several years (Milkov 2000; Dimitrov 2002, 2003; Etiope and Klusman 2002; Kopf 2002, 2003; Milkov et al. 2003; Etiope and Milkov 2004). In one of the most recent papers, Kopf (2003) claims to report a reliable estimate of the global CH4 emission from MVs. However, the significance and usefulness of the estimate presented by Kopf (2003) are rather poor. The used dataset is smaller than in previous studies (although the author makes a reverse claim), and some previously published works are misquoted and misinterpreted. Numerous arithmetic mistakes made during simple calculations and data manipulations lead to confusing results and conclusions. In this comment, we highlight some of the most significant problems with the estimates published by Kopf (2003).
    Description: Published
    Description: 490-492
    Description: 4.5. Degassamento naturale
    Description: JCR Journal
    Description: reserved
    Keywords: Methane ; mud volcanoes ; 04. Solid Earth::04.08. Volcanology::04.08.01. Gases
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    Publication Date: 2022-02-16
    Description: A new estimate of global methane emission into the atmosphere from mud volcanoes (MVs) on land and shallow seafloor is presented. The estimate, considered a lower limit, is based on 1) new direct measurements of flux, including both venting of methane and diffuse microseepage around craters and vents, and 2) a classification of MV sizes in terms of area (km2) based on a compilation of data from 120 MVs. The methane flux to the atmosphere is conservatively estimated between 6 and 9 Mt y)1. This emission from MVs is 3–6% of the natural methane sources and is comparable with ocean and hydrate sources, officially considered in the atmospheric methane budget. The total geologic source, including MVs, seepage from seafloor, microseepage in hydrocarbon-prone areas and geothermal sources, would amount to 35–45 Mt y)1. The authors believe it is time to add this parameter in the Intergovernmental Panel on Climate Change official tables of atmospheric methane sources.
    Description: Published
    Description: 997-1002
    Description: 4.5. Degassamento naturale
    Description: JCR Journal
    Description: reserved
    Keywords: Methane ; Mud volcanoes ; 03. Hydrosphere::03.04. Chemical and biological::03.04.05. Gases
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...