Search results for "Formic Acid"
showing 10 items of 108 documents
Anharmonic Vibrational Spectrum and Experimental Matrix Isolation Study of Thioformic Acid Conformers -- Potential Candidates for Molecular Cloud and…
2021
Thioformic acid (TFA) is the sulfur analog of formic acid, the simplest organic acid. It has three analogues HCOSH, HCSOH, and HCSSH, each of them having two rotational isomeric (rotameric) forms: trans and cis where the trans form is energetically more stable. In this article, we study computational energetics and anharmonic vibrational spectrum of TFA including overtone and combination vibrations. We also studied experimental photoisomerization and photodecomposition channels of HCOSH molecules with different wavelengths. We suggest that TFA is a potential sulfur containing candidate molecule for interstellar and planetary observations and discuss these in a light of different radiation e…
Physicochemical uptake and release of volatile organic compounds by soil in coated-wall flow tube experiments with ambient air
2019
Volatile organic compounds (VOCs) play a key role in atmospheric chemistry. Emission and deposition on soil have been suggested as important sources and sinks of atmospheric trace gases. The exchange characteristics and heterogeneous chemistry of VOCs on soil, however, are not well understood. We used a newly designed differential coated-wall flow tube system to investigate the long-term variability of bidirectional air–soil exchange of 13 VOCs under ambient air conditions of an urban background site in Beijing. Sterilized soil was investigated to address physicochemical processes and heterogeneous/multiphase reactions independently from biological activity. Most VOCs revealed net depositio…
Hyperfine structure in the rotational spectra of trans-formic acid: Lamb-dip measurements and quantum-chemical calculations
2010
Context. Formic acid, HCOOH, is the simplest organic acid and the first that has been identified in the interstellar medium. Its astrophysical relevance has motivated this spectroscopic study. Aims. The aim of this investigation is to provide very accurate rest frequencies for the trans isomer of HCOOH as well as to improve the spectroscopic and hyperfine parameters available in the literature for this molecule. Methods. The Lamb-dip technique has been exploited in order to record the rotational spectrum of trans-HCOOH at sub-Doppler resolution in the millimeter- and submillimeter-wave frequency ranges and, when possible, to resolve the hyperfine structure due to the hydrogen nuclei. THz me…
Effect of air pressure on the electro-Fenton process at carbon felt electrodes
2018
Abstract The effect of air pressure on electro-Fenton (PrEF process) was evaluated using two organic substances (maleic acid and Acid Orange 7) as model organic pollutants. First experiments were performed using a conventional carbon felt (CF) cathode. At room pressure, a slow removal of maleic acid was obtained, together with the generation of formic acid. Conversely, using pressurized air, the removal of maleic acid was dramatically accelerated and the formation of formic acid was not detected. The utilization of a carbon felt modified by the deposition of carbon black + PTFE mixture (MCF) and of pressurized air allowed to achieve even faster and almost total (>95%) removal of total organ…
Electrochemical conversion of carbon dioxide in pressurized electrochemical cells
2019
To limit the negative effect of carbon dioxide as a greenhouse gas, an interesting approach is the utilization of Carbon Capture and Conversion (CCC) methodology, which is focused on the use of CO2 waste as a feedstock to produce added-value products by using the excess electric energy from renewable source [1]. In this framework, an increasing attention has been devoted to the electrochemical conversion of carbon dioxide to formic acid in water [2-3] or CO [1]. Since the main hurdle of the CO2 reduction from aqueous solution is the low CO2 solubility in water, in this work, the utilization of pressurized electrochemical cells is evaluated. The effect of various operating parameters, includ…
Plasma pharmacokinetics and tissue distribution study of cajaninstilbene acid in rats by liquid chromatography with tandem mass spectrometry
2010
Cajaninstilbene acid (CSA; 3-hydroxy-4-prenyl-5-methoxystilbene-2-carboxylic acid) is a major active constituent of pigeonpea leaves, has been proven to be effective in clinical treatment of diabetes, hepatitis, measles and dysentery. A rapid and sensitive liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed and validated for the determination of CSA in rat plasma and various tissues (brain, heart, lung, liver, spleen, small intestine and kidney) of rat for the first time. Rat plasma and tissue distribution pre-treated by protein precipitation with acetoacetate was analyzed using LC-MS/MS with an electrospray ionization (ESI) interface, and isoliquiritigenin was us…
Premio di Laurea “Ametek Scientific Instruments”: Electrochemical Conversion of Carbon Dioxide to Formic Acid. Study of the Effect of the Operating P…
2017
Electrochemical conversion of CO2 is considered one of the more appealing approaches to introduce renewable energy in the chemical and energy chain and to mitigate the greenhouse gases effect. In this work, the reduction of carbon dioxide was performed in undivided electrochemical cell to produce formic acid, which is one of the highest value-added chemicals and economically feasible for large-scale applications (1). It is well known that the main hurdle of the reduction of CO2 from water solution is the low CO2 solubility in water. In order to overcome this obstacle, a specific investigation on the effect of the CO2 pressure and other operating parameters at tin flat cathodes was carried o…
Partial photocatalytic oxidation of glycerol in TiO2 water suspensions
2010
2nd European Conference on Environmental Applications of Advanced Oxidation Processes -- SEP 09-11, 2009 -- Nicosia, CYPRUS
Guidelines for the Assessment and the Validation of the Rate Law of Slurry Photocatalytic Reactions
2017
The assessment of the rate law of slurry photocatalytic reactions appears to be a hard task, mainly because in this type of reactions the average rate of reaction, which is experimentally observed in a real reactor, could be very different from the “true” (intrinsic) rate of reaction, which cannot be measured directly. In the present work, it is shown how a proper mathematical model allows the utilization of the differential and/or the integral methods of kinetic analysis. The mathematical model must take into account not only the momentum and the mass balances, but also the radiative transfer equation. However, the discrimination among different proposed kinetic laws remains difficult sinc…