Search results for "METHANE"
showing 10 items of 1763 documents
ChemInform Abstract: An Easy Access to Fused Chromanones via Rhodium Catalyzed Oxidative Coupling of Salicylaldehydes with Heterobicyclic Olefins.
2016
Diazabicyclic and urea-derived bicyclic olefins react with salicylaldehydes to produce various types of fused chromanone systems of biological interest in a single step (mechanism).
Anaerobic treatment of urban wastewater in membrane bioreactors: evaluation of seasonal temperature variations
2014
The objective of this study was to evaluate the effect of seasonal temperature variations on the anaerobic treatment of urban wastewater in membrane bioreactors (MBRs). To this aim, sludge production, energy recovery potential, chemical oxygen demand (COD) removal and membrane permeability were evaluated in a submerged anaerobic MBR fitted with industrial-scale membrane units. The plant was operated for 172 days, between summer and winter seasons. Sludge production increased and energy recovery potential decreased when temperature decreased. COD removal and membrane permeability remained nearby stable throughout the whole experimental period.
Biomethane Production from Anaerobic Co-Digestion of Selected Organic Fraction of Municipal Solid Waste (OFMSW) with Sewage Sludge: Effect of the Ino…
2021
The aim of this study was to evaluate the effect of the inoculum to substrate ratio (ISR) and the mixture ratio between organic fraction of municipal solid waste (OFMSW) and sewage sludge (SS) on the methane production potential achievable from anaerobic co-digestion (AcoD). Biochemical Methane Potential (BMP) assays at mesophilic temperature were used to determine the best AcoD configuration for maximizing methane yield and production rate, as well as to address possible synergistic effects. The maximum methane yield was observed at ISR of 1 and 60% OFMSW: 40% SS as co-digestion mixture, whereas the highest methane production rate was achieved at ISR of 2 with the same mixture ratio (207 m…
Triphenyl[(4-phenylbenzoyl)methyl]phosphonium trifluoromethanesulfonate
2010
In the cation of the title compound, C32H26OP+·CF3O3S−, the dihedral angle between the benzene rings of the biphenyl group is 42.37 (8)°. In the crystal, the cations and anions interact through intermolecular C—H...O hydrogen bonds, forming chains parallel to the b axis. These chains are further linked by C—H...π stacking interactions into layers parallel to the bc plane.
Dipole Moment Surface of the van der Waals Complex CH4–N2
2010
The interaction-induced dipole moment surface of the van der Waals CH(4)-N(2) complex has been calculated for a broad range of intermolecular separations R and configurations in the approximation of the rigid interacting molecules at the MP2 and CCSD(T) levels of theory using the correlation-consistent aug-cc-pVTZ basis set with the basis set superposition error correction. The simple model to account for the exchange effects in the range of small overlap of the electron shells of interacting molecules and the induction and dispersion interactions for large R has been suggested. This model allows describing the dipole moment of van der Waals complexes in analytical form both for large R, wh…
The hyperfine structure in the rotational spectra of bromofluoromethane: Lamb-dip technique and quantum-chemical calculations
2008
International audience; The hyperfine structure in the rotational spectra of six isotopic species of bromofluoromethane, namely CH2{79}BrF, CH2{81}BrF, CDH{79}BrF, CDH{81}BrF, CD2{79}BrF, and CD2{81}BrF, has been investigated using the Lamb-dip technique in the submillimeter-wave frequency range. Measurements as well as assignment procedures have been supported by high-level quantum-chemical calculations of the hyperfine parameters at the coupled-cluster level. For all species, the accuracy of the determined rotational and centrifugal distortion constants as well as the bromine quadrupole-coupling constants have been improved with respect to available literature data, whereas the full bromi…
New phosphathiamacrocycles containing polypypiridine units
2006
Abstract A new 2,2′-bipyridine-based phosphadithiamacrocycle: 3,3′-5-phenyl-2,8-dithia-5-phospha[9]-2,2′-bipyridinophane (L) has been synthesized by reacting 6,6′-bis(bromomethyl)-2,2′-bipyridine and dilithium 3-phenyl-3-phosphapenta-1,5-dithiolate. The phosphoryl derivative: 3,3′-5-oxo-5-phenyl-2,8-dithia-5-phospha[9]-2,2′-bipyridinophane (Lox) synthesized by direct oxidation of L at open atmosphere. Both compounds have been isolated as white solids containing different amounts of LiBr. The reaction of acetonitrile solutions of these solids with Fe(II) perchlorate gave the complexes [FeBr(L)](ClO4) · 2H2O and [FeBr(Lox)](ClO4) · 3H2O, which were crystallized as [FeBr(L)]Br · H2O and [ FeBr…
OH–π and halogen–π interactions as driving forces in the crystal organisations of tri-bromo and tri-iodo trityl alcohols
2008
The trityl alcohols bearing three bromine or three iodine atoms at the para-positions of the aromatic units, have been known for more than a hundred years. In our case these compounds have been synthesized in one-pot sequence starting from the 1,4-dihalogenobenzenes via mono-lithiation and the successive reaction with diethylcarbonate. The compounds have been crystallized from different solvent mixtures leading to one structure of bromo- (A) and three structures of iodo trityl alcohols (B–D). The inclusion of dichloromethane (C) or benzene (D) in the crystalline lattices has been observed. In all cases the OH–π and halogen–π (and in one case the halogen-halogen and CH-O weak) contacts play …
A Solar Photothermocatalytic approach for the CO2 conversion: Investigation of different synergisms on CoO-CuO/Brookite TiO2-CeO2 catalysts
2022
Abstract The photoactive features of the least common polymorph of TiO2, i.e. brookite, were combined with the thermocatalytic redox ones of cerium oxide, focusing on the effects of the addition of small amounts of Co-Cu oxides for the solar CO2 conversion. By considering the characterization data, a surface segregation of the hosted metal oxides on the TiO2-CeO2 composite was evidenced, and their presence increased the amount of oxygen vacancies and improved the charge carriers separation. The bimetallic oxides-based sample was the most performing one in the photocatalytic carbon dioxide reduction at room temperature. The formation of carbon monoxide and methane was 5 and 0.5 μmol g−1h−1, …