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... Lowering the temperature of a biological sample reduces the pace of biochemical metabolism and ultimately stops it altogether. This process, in combination with rewarming the sample with minimal tissue damage, is the essence of cryopreservation. A key obstacle to successful cryopreservation is that, as the biological material is cooled, liquid water within the sample may reorganize into a more sta ...
... Using DEM simulations, the paper examines the different types of behaviour as the gas velocity is increased to cover the complete range from fixed bed to homogeneous expansion, bubbling, turbulent and fast fluidisation. The paper highlights the transitions between the various regimes. At minimum fluidisation velocity, Umf, the structure of the bed is isostatic. When the gas velocity U is increased ...
... Density functional theory (DFT) was used to investigate the adsorption of lactic acid molecules on the surface of (4,4), (5,5), (6,6) and (7,7) single-walled carbon nanotubes (SWCNTs). A hybrid DFT method with the inclusion of dispersion correction was employed and the results compared to those obtained from the non-corrected DFT method. The energies and optimum distances for two different configu ...
energy use and consumption; environmental impact; gases; industry; linear models; traffic
Abstract:
... Reduction of the environmental impact of cars represents one of the biggest transport industry challenges. Beyond more efficient engines, a promising approach is to use eco-driving technologies that help drivers achieve lower fuel consumption and emission levels. In this study, a real-time microscopic fuel consumption model was developed. It was designed to be integrated into simulation platforms ...
chemical reactions; chemical structure; chlorine; electrospray ionization mass spectrometry; gases; lithium; lithium chloride; nitrogen; organic chemistry; organic compounds; protons
Abstract:
... In cold THF and in the presence of LiCl, a lithium pyrrolidinylamide forms a 1:1 mixed aggregate, which is observed directly by ESI-MS. Gas-phase protonation of this species leads to selective transfer of H⁺ to the chlorine, suggesting that LiCl shields the amide nitrogen and prevents its direct protonation. ...
boilers; byproducts; carbon dioxide; case studies; electricity costs; energy; energy conservation; gases; industry; iron; linear programming; models; operating costs; planning; statistical analysis; steel
Abstract:
... In integrated steel works, byproduct gases are generated in the iron and steel making process, which accounts for approximately 30% of the total energy involved. The efficient utilisation of these gases is significant for energy saving and CO2 reduction in the iron and steel industry. In this paper, a mixed integer linear programming (MILP) model was proposed to optimise the byproduct gas manageme ...
... A change of the forestry management approach where semi-natural forests are re-created after logging instead of tree plantations will contribute to a sustainable forestry. Such a change will increase resilience to damages on trees, thus contributing to a more reliable supply of wood, improve reindeer husbandry, and reduce climate-driving gases. Furthermore, re-creation of semi-natural forests will ...
activation energy; cracking; gases; kinetics; models; oil shale; oils; pyrolysis; temperature; volatilization; Green River
Abstract:
... A simple model is presented that accounts for the effects of temperature, pressure, and externally supplied gas flow rate on the kinetics of oil evolution during oil shale pyrolysis. The primary transport mechanism for generated oil from retorting oil shale particles is, by far, vaporization in co-generated gases. The simple model is based on the concept that an equivalent volatility of the oil mu ...
... Thiophosphoryl nitrenes, R₂P(S)N, are thiazirine-like intermediates that have been chemically inferred from trapping products in early solution studies. In this work, photolysis of the simplest thiophosphoryl azide, F₂P(S)N₃, in solid noble-gas matrices enabled a first-time spectroscopic (IR and UV–vis) identification of the thiophosphoryl nitrene F₂P(S)N in its singlet ground state. Upon visible- ...
... The thermo-mineral fluids discharges of Montecatini Terme (Northern Apennines, Tuscany, Italy) have been exploited since the Roman times and despite the fact that this thermal complex is one of the biggest in Europe, the most recent geochemical investigations were published almost 40years ago. To fill this gap, in this paper a detailed geochemical and isotopic investigation on the main thermal spr ...
gases; momentum; equations; models; electrochemistry; mass transfer; anodes
Abstract:
... This paper presents electrochemical impedance simulation of a solid oxide fuel cell anode. The model takes in to account the gas-phase transport processes both in the gas channel and within the porous electrode and couples the gas transport processes with the electrochemical kinetics. The gas phase mass transport is modeled using the transient conservation equations (mass, momentum and species equ ...
active sites; anodes; electrolytes; films (materials); fuel cells; fuels; gases; iron; nanosheets; nickel; strontium
Abstract:
... To achieve high power density in intermediate-temperature solid oxide fuel cells (IT-SOFCs), we introduce a dense La(Sr)Fe(Mn)O₃₋δ (LSFM) nano-film anode between a Ni–Fe metallic substrate and a LaGaO₃-based oxide electrolyte. Although a three-phase boundary (TPB) is believed to be required for anode active sites, the cell with the LSFM mixed-conductor thin-film anode exhibited much improved power ...
... In cement production, direct measurements of thermal and chemical variables are often unfeasible as a consequence of aggressive environments, moving parts and physical inaccessibility, and therefore prediction models are essential tools in these types of industrial applications. This article addresses the problem of the numerical prediction of the CaCO3 calcination process, which is the first and ...
... Industrial gases such as nitrogen, oxygen, argon, and helium are easily contaminated with water during production, transfer and use, because there is a high volume fraction of water in the atmosphere (approximately 1.2% estimated with the average annual atmospheric temperature and relative humidity). Even trace water (<1 parts per million by volume (ppmv) of H2O, dew point < −76 °C) in the industr ...
... Acid gases carbon dioxide (CO₂) and hydrogen sulfide (H₂S) are important and highly undesirable contaminants in natural gas, and membrane-based removal of these contaminants is environmentally attractive. Although removal of CO₂ from natural gas using membranes is well established in industry, there is limited research on H₂S removal, mainly due to its toxic nature. In actual field operations, wel ...
activation energy; active sites; adsorption; cyclohexenes; epoxidation reactions; gases; hydrogen peroxide; kinetics; porous media
Abstract:
... A kinetic analysis of gas-phase cyclohexene epoxidation by H2O2 over mesoporous TS-1 was performed. The production of cyclohexene oxide was very stable with high selectivity. Based on the kinetic analysis, the gas-phase mechanism is proposed to be similar to that of the liquid-phase reaction: an Eley–Rideal type mechanism, in which the reaction between a Ti–OOH intermediate and the physisorbed alk ...
... New particle formation (NPF) was investigated at a coastal background site in Southwest Spain over a four-year period using a Scanning Particle Mobility Sizer (SMPS). The goals of the study were to characterise the NPF and to investigate their relationship to meteorology, gas phase (O3, SO2, CO and NO2) and solar radiation (UVA, UVB and global). A methodology for identifying and classifying the NP ...
catalysts; copper; enantiomers; gases; ligands; mass spectrometry; rapid methods; spectrometers
Abstract:
... A gas‐phase method for rapidly assaying the enantioselectivity of metal‐centered catalysts is presented. It relies on gas‐phase equilibrium measurements in a quadrupole ion trap mass spectrometer. A group of well‐established C₂‐symmetric bis‐oxazoline copper(I) complexes was used to identify chiral probe reagents that are capable of profiling the quality of the asymmetric environment provided by t ...
... Data on intermolecular noncovalent interactions of nitrogen base components of nucleic acid with organic polyethers are of interest both for fundamental molecular biophysics and for applications in the production of pharmaceutical organic nanoparticles. In the present work, systems composed of pyrimidine nitrogen base cytosine (Cyt) or its methyl derivatives and polyethylene glycol PEG-400 oligome ...
... 5-hydroxymethylfuraldehyde (5-HMF) and simpler compounds, such as levulinic acid (LA) and glyceraldehyde, are platform molecules produced by the thermal acid-catalyzed dehydration of carbohydrates coming from biomass. Understanding sugar degradation pathways on a molecular level is necessary to increase selectivity, reduce degradation by-products yields and optimize catalytic strategies, fundament ...
... Flash pyrolysis (Py) in combination with gas chromatography (GC) and mass spectrometry are often used to elucidate the structure of geomacromolecules such as kerogens, coals, asphaltenes and humic acids by analyzing their low molecular weight pyrolysis products. Most previous work restricts itself to C6+ pyrolysis products with only a few reports on the quantitative measurement of individual C1–C5 ...
... In the present work, chitosan and magnesium hydroxide (MH) were successfully deposited on the surface of flexible polyurethane foam (FPUF). Due to the strong interaction, the coated foam with 10.3 wt% weight-gain could be prepared by constructing one chitosan layer and one MH layer. Scanning electron microscopy images showed that this coating continuously covered the substrate. The combustion prop ...
... A novel and efficient process for the production of 1,2-propylene glycol with high productivity and high selectivity from biomass-derived lactic acid over CuO was investigated. As a result, CuO exhibited a high catalytic activity while Zn acted as a reductant for the conversion of lactic acid to 1,2-propylene glycol. Among the various reaction parameters, such as catalysts, reductants, temperature ...
... This work presents the results of further development of incremental (group contribution) methods for prediction of the gas transport parameters (permeability (P) and diffusion (D) coefficients) of amorphous glassy polymers. The source of information was a big Database that comprises the P and D values for about 900 polymers. The method of the modified atomic contributions was revisited using much ...
... In this paper, we have prepared an antibacterial material of PVA/l-histidine (L-H)/Ag fibers by electrospinning in a double nozzle for the first time. The composite fibers were crosslinked by the mixture of glutaraldehyde and hydrogen chloride gas. After that, the fibers were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Energy Dispersive X-ray Spectr ...
... A combined system that consists of a pulsed sampling system, a capillary column as a transfer line and a mass spectrometer is used for online monitoring of complicated mixtures of gases and VOCs produced in a bioreactor. The combined system had long term stability and robust operation together with significant separation capability when the transfer line was a coated capillary column. It appeared ...
aerosols; chemical pollutants; gases; pH; pathogens; rain; urban areas; water harvesting; watersheds
Abstract:
... This work proposes to consider the quality of roof-collected rainwater as the sum of three main stages. In the first one, rainfall washes out the urban atmosphere and scavenges contaminants from aerosols, gases and thin volatile particles. The second stage refers to the catchment, in which occurs contamination due to the wash-off of particles settled on the roof’s surface as well as the scavenging ...
... Three new binuclear solid lanthanide complexes with the general formula [Ln(2,3-DClBA)3(terpy)(H2O)]2(Ln=Pr(1), Sm(2), Eu(3); 2,3-DClBA=2,3-dichlorobenzoate; terpy=2,2′:6′2″-terpyridine), have been synthesized and characterized. The powder XRD and single-crystal structures of the title complexes indicate that all the complexes are isomorphous. The two lanthanide ions in each complex are linked by ...
... Application of respirometric tools in wastewater engineering fields is still not getting familiarity and acceptance by academy or industry in developing countries as compared to the use of conventional biochemical oxygen demand (BOD) approach. To justify the applicability of respirometry, a low-cost respirometric device suitable for monitoring biodegradation process in wastewater has been develope ...
... Torrefaction is a treatment which serves to improve the properties of biomass in relation to thermochemical processing techniques for energy generation. In this study, the torrefaction of sewage sludge, which is a non-lignocellulosic waste was investigated in a horizontal tubular reactor under nitrogen flow at temperature ranging from 150 to 400°C, for torrefaction residence time varying from 0 to ...
... Understanding the adsorption process of volatile organic compounds (VOCs) on various surfaces is essential in the realms of atmospheric, environmental and pollution remediation science. In this study, we investigated the adsorption of selected VOCs (benzene and toluene) on an ideally homogeneous liquid mercury (Hg₍ₗ₎) surface using a surface sensitive nonlinear spectroscopic method of second harmo ...
... Various borenium ion affinities toward three ligands (L′ = NH₃, HCHO and Cl⁻) have been evaluated by DFT calculations in the gas-phase and in solvent (CH₂Cl₂). The gas-phase results have been rationalized on the basis of quantitative decomposition of the total binding energy into contributions from electrostatic, orbital, dispersion and Pauli interactions, and energy needed to deform the interacti ...
adsorption; chemical reactions; crystal structure; gases; porosity; vanadium
Abstract:
... A vanadium(iv) pyrazolate-based open metal–organic polyhedron of [V₃(μ₃-O)O(OH)₂(μ₄-BPD)₁.₅(μ-HCOO)₃] (BDP = benzene-1,4-bipyrazolate) formulation gives rise to a porous crystal structure exhibiting micro and mesoporosity which is useful for selective adsorption of gases. ...
... Superalkalies, due to lower ionization potentials than alkalies, possess potential reducing capability and can be used in the synthesis of a variety of charge transfer salts. In order to check whether superalkali hydroxides are as basic as a typical alkali hydroxide, we have performed a systematic investigation on the hydroxides of small FLiₙ (n = 2–5) superalkali clusters. The equilibrium structu ...
... We combine first-principles atomistic thermodynamics with a Wulff–Kaichew construction to determine the equilibrium shape of Ag particles supported on α-Al2O3(0001) under gas-phase conditions representative for ethylene epoxidation. The formation of three-dimensional truncated octahedra is predicted for both the Al-terminated (AlO3Al-R) and the fully hydroxylated O-terminated (H3O3Al-R) alumina su ...
absorption; air pollution; aqueous solutions; distillation; gases; heat; hexane; human health; organic production; perfluorocarbons; solubilization; solvents; surfactants
Abstract:
... n-Hexane is widely used in industrial production as an organic solvent. As an industrial exhaust gas, the contribution of n-hexane to air pollution and damage to human health are attracting increasing attention. In the present study, aqueous solutions of two fluorocarbon surfactants (FSN100 and FSO100) were investigated for their properties of solubilization and dynamic absorption of n-hexane, as ...
... The reaction of methylcarbonate ionic liquids with H₂S or H₂Se offers a highly selective synthesis of analytically pure, well-defined and soluble hydrosulphide and hydroselenide organic salts of general interest. Among them, imidazolium hydrochalcogenides show an astonishingly high volatility for cation-aprotic ILs, which allows their quantitative sublimation below 100 °C/10⁻² mbar and actually re ...
... Understanding on a molecular level the acid‐catalysed decomposition of the sugar monomers from hemicellulose and cellulose (e.g. glucose, xylose), the main constituent of lignocellulosic biomass is very important to increase selectivity and reaction yields in solution, key steps for the development of a sustainable renewable industry. In this work we reported a gas‐phase study performed by electro ...
... Acid gases such as SO₂ can be absorbed by ionic liquids (ILs) because of their unique properties. In this work, we developed a new approach for improving SO₂ absorption by novel acylamido-based anion-functionalized ILs. Several kinds of such ILs with different structures of acylamido group (anionic acylamide) were designed, prepared, and used for efficient capture of SO₂. It was shown that these a ...
... The E-PPR78 model is a predictive version of the widely used Peng–Robinson equation of state in which the binary interaction parameters are estimated by a group-contribution method. With the 24 groups available before the writing of this paper, such a model could be used to predict fluid phase equilibrium of systems containing hydrocarbons, permanent gases (CO₂, N₂, H₂S, H₂, CO, He, and Ar), merca ...
carbon dioxide; carbon sequestration; coal; energy; gases; greenhouse gas emissions; greenhouse gases; labor force; mining; models; oil shale; China
Abstract:
... China is now the world's largest user of coal, and also has the highest greenhouse gas emissions associated with the mining and use of coal. In the mining sector, the interests of workforce safety coincide with those of GHG (greenhouse gas) management. While the traditional approach to ensuring workforce safety in coal mines was simply to vent the hazardous gases to the atmosphere, thus increasing ...
adsorption; desorption; equations; evaporation; gases; gravimetry; hysteresis; mass transfer; porous media; relative humidity; silica; water uptake
Abstract:
... We have investigated the adsorption and desorption of water in two-dimensional hexagonal mesoporous silica (MPS) with three different pore dimensions. All the adsorption–desorption isotherms exhibited type V behavior with significant hysteresis. Hysteresis was observed in the transient region between the layer adsorption state and the pore filling state, where capillary condensation and evaporatio ...
... The natural presence of methane oxidizing bacteria (MOB) in landfill soils can stimulate the bio-chemical oxidation of CH4 to CO2 and H2O under suitable environmental conditions. This mechanism can be enhanced by amending the landfill cover soil with organic materials such as biochars that are recalcitrant to biological degradation and are capable of adsorbing CH4 while facilitating the growth and ...
adsorption; aluminum hydroxide; bitumen; carbon dioxide; chemical elements; desorption; energy; gases; geometry; hydrogen bonding; hydrophobic bonding; kaolinite; methodology; models; naphthalene; oil sands; oils; solvents; temperature; thermodynamics; van der Waals forces
Abstract:
... The geometry of phenanthridine, benzothiophene, tetralin, and naphthalene representative of the heterocyclic, naphthenic, and aromatic components of bitumen adsorbed on kaolinite is optimized using density functional theory and periodic boundary conditions in gas phase. These bitumen model compounds preferentially adsorb on the aluminum hydroxide surface of kaolinite with energy decreasing in the ...
... Thermal response measurements based on optical adsorption calorimetry are presented as a versatile tool for the time-saving and profound characterization of the pore structure of porous carbon-based materials. This technique measures the time-resolved temperature change of an adsorbent during adsorption of a test gas. Six carbide and carbon materials with well-defined nanopore architecture includi ...
carbon monoxide; chemical industry; engineering; gases; phosphorus; pollution; raw materials; recycling; value added
Abstract:
... Yellow phosphorous is an important raw material in the chemical industry. However, during the production of yellow phosphorous, high concentrations of carbon monoxide and other impurities are released. Without appropriate purification and removal, this off gas has potential to cause severe pollution problems once released. Purified yellow phosphorous off gas can be beneficially reused as a raw mat ...
catalytic activity; chemical analysis; gases; instrumentation; volatile organic compounds
Abstract:
... Cataluminescence (CTL) emitted on the surface of solid materials during a catalytic reaction is a very interesting phenomenon, which gives a novel, powerful tool for chemical analysis. Nanomaterial-assisted CTL is a promising transduction principle for gas sensing, and its main features of high sensitivity and long lifetime are also favorable for developing a wide array of analytical devices. This ...
Salmonella; air pollution; data collection; gases; genotoxicity; monitoring; mutagenicity; particulates; pollutants; polycyclic aromatic hydrocarbons; urban areas
Abstract:
... Commonly the atmospheric pollution research is focussed on particulate indicators especially when mutagenicity was studied. On the other hand the volatile and semi-volatile compounds no adsorbed on to the particles can be genotoxic and mutagenic. Moreover some mutagenic compounds, such as polycyclic aromatic hydrocarbons, are present both in the particulate and in the gas-phase in according to che ...
... Aerosol emissions from construction sites have a strong impact on local air quality. The chemical and physical characteristics of particles and trace gases emitted by earthworks (excavation and loading of soil as well as traffic on unpaved roads) and road works (asphalt sawing, smashing, soil compacting, asphalt paving) have therefore been addressed in this study by using a mobile set-up of numero ...
amino acids; astringency; chemical reactions; chemical structure; energy; gases; humans; mass spectrometry; peptides; polyphenols; proteins
Abstract:
... Energy Resolved Mass Spectrometry of peptide-polyphenol complexes was used to characterize the affinity of a selection of 21 polyphenols for peptides from human salivary basic Proline Rich Proteins (PRPb) having variable lengths. The affinity scale determined in the gas phase for a 14 amino acid long peptide is in agreement with results obtained in the liquid phase with the same PRPb probe immobil ...
... Diverse, severe, and location-specific impacts on agricultural production are anticipated with climate change. The last IPCC report indicates that the rise of CO₂ and associated “greenhouse” gases could lead to a 1.4 to 5.8 °C increase in global surface temperatures, with subsequent consequences on precipitation frequency and amounts. Temperature and water availability remain key factors in determ ...
Richard W Battarbee; Simon Turner; Handong Yang; Neil L Rose; Peter M Smyntek; Paula J Reimer; Frank Oldfield; Vivienne J Jones; Roger J Flower; Kevin Roe; Ewan Shilland; Maarten Blaauw
Bacillariophyceae; acid deposition; acidification; air pollutants; air pollution; combustion; emissions; forests; fossil fuels; gases; heathlands; heavy metals; lakes; landscapes; pH; peat; pollen; sediments; soil; stable isotopes; sulfur; surface water; watersheds; United Kingdom
Abstract:
... Despite the extensive geographical range of palaeolimnological studies designed to assess the extent of surface water acidification in the United Kingdom during the 1980s, little attention was paid to the status of surface waters in the North York Moors (NYM). In this paper, we present sediment core data from a moorland pool in the NYM that provide a record of air pollution contamination and surfa ...
air; air pollution; chemical analysis; fungi; gas chromatography; hydrogen sulfide; landfills; odor compounds; psychrophilic bacteria; quantitative analysis; spring; sulfur; summer; wastes
Abstract:
... Microbiological and chemical analysis of air was carried out on the area of landfill of wastes other than inert or hazardous. The landfill covers 20 ha and 40 000 Mg of wastes is deposited annually. Municipal waste is not segregated at the landfill. The research was conducted in April, May and November 2012. Number of the psychrophilic and mesophilic bacteria and fungi was estimated by a culture-b ...
Vanessa Silveira Barreto Carvalho; Edmilson Dias Freitas; Leila Droprinchinski Martins; Jorge Alberto Martins; Caroline Rosario Mazzoli; Maria de Fátima Andrade
air pollution; air quality; cities; emissions; ethanol; gases; issues and policy; natural gas; ozone; particulates; pollutants; sugarcane; winter; Brazil
Abstract:
... Fourteen years of regulated air pollutants concentrations were analyzed in order to characterize the benefits of Brazil's emission control policies on air quality conditions and to evaluate the temporal patterns between 1996 and 2009 over the Metropolitan Area of São Paulo (MASP). MASP includes one of the largest cities in the world (São Paulo) and its light-duty vehicular fleet has a very importa ...
... The removal of volatile organic compounds is an important aspect of sustainability and environmental protection. Catalytic oxidation is one of the most efficient routes to achieve this. The K⁺ form of an aluminium-rich Beta zeolite-supported Pt nanoparticle (2.2 nm) [Pt/KBeta-seed-directed synthesis (SDS)] catalyst is very active for the low-temperature catalytic removal of toluene and results in ...
aerosols; air quality; alkali treatment; ammonia; carbonization; coal; gases; nitrogen dioxide; physicochemical properties; principal component analysis; sulfur; sulfur dioxide; India
Abstract:
... The objective of this study is to determine the concentrations of gaseous species and aerosols in and around a non-recovery type coke making oven using high sulphur coals. In this paper, physico-chemical properties of the feed coal sample are reported along with the collection and measurement of the emitted gases (SO2, NO2, and NH3) and aerosol particles (PM2.5, PM10) during the coal carbonization ...
alcohols; chemical reactions; esters; gases; ions; moieties; organic chemistry; protons
Abstract:
... Upon activation in the gas phase, protonated alkyl dihydrocinnamates undergo an alcohol loss. However, the mechanism followed is not a simple removal of an alkanol molecule after a protonation on the alkoxy group. The mass spectrum of the m/z 166 ion for deuteron-charged methyl dihydrocinnamate showed two peaks of 1:5 intensity ratio at m/z 133 and 134 to confirm that the incipient proton is mobil ...
ammonia; catalysts; chemical bonding; dissociation; electron transfer; gases; hydrides; hydrogen; ligands; oxidation; rhodium
Abstract:
... The catalytic hydrogenolysis of the titanium–amide bond in (η⁵-C₅Me₄SiMe₃)₂Ti(Cl)NH₂ to yield free ammonia is described. The rhodium hydride, (η⁵-C₅Me₅)(py-Ph)RhH (py-Ph = 2-phenylpyridine), serves as the catalyst and promotes N–H bond formation via hydrogen atom transfer. The N–H bond dissociation free energies of ammonia ligands have also been determined for titanocene and zirconocene complexes ...
... Use of gas-phase amendments for in situ remediation of inorganic contaminants in unsaturated sediments of the vadose zone may be advantageous, but there has been limited development and testing of gas remediation technologies. Treatment with ammonia gas has a potential for use in treating inorganic contaminants (such as uranium) because it induces a high pore-water pH, causing mineral dissolution ...
... New ammonia and amine sensing materials based on hybrid polyaniline/titanium dioxide nanocomposites were synthesized by a one-pot chemical polymerization. Particular attention was paid to the influence of TiO₂ nanoparticles and the surface active dopants on the structure–property relationship of the nanocomposites in terms of their morphology, composition, electrical and sensing properties. Dodecy ...
detergents; dissociation; gases; ions; mass spectrometry; membrane proteins; micelles; protein structure; solubility; solubilization
Abstract:
... Noncovalent mass spectrometry (MS) is emerging as an invaluable technique to probe the structure, interactions, and dynamics of membrane proteins (MPs). However, maintaining native-like MP conformations in the gas phase using detergent solubilized proteins is often challenging and may limit structural analysis. Amphipols, such as the well characterized A8-35, are alternative reagents able to maint ...
... Obtaining accurate temperature measurements with thermocouples in flame environments is challenging due to the effects of radiative heat losses, as these losses are difficult to quantify. Efforts to minimize radiative losses by, for example, suction pyrometry often result in a significant sacrifice in spatial resolution. In this work, a new experimental methodology is presented that both minimizes ...
density; explosions; flow; gases; pressure; problem solving; velocity
Abstract:
... In this paper, we have found an exact similarity solution of the point explosion problem concerning spherical symmetric flows in a relaxing gas. In contrast to situations without relaxation, the inclusion of relaxation effects implies constraint conditions. We assume the solution of the problem in a similarity form which transform the given PDEs with jump conditions to a set of ODEs with boundary ...
... Using proton-transfer reactions in a Fourier transform ion cyclotron resonance mass spectrometer and correlated molecular orbital theory at the G3(MP2) level, gas-phase acidities (GAs) and the associated structures for amides corresponding to the common amino acids have been determined for the first time. These values are important because amino acid amides are models for residues in peptides and ...
... This work reports the study on the interactions of sulfur-doped fullerenes with halogens and halides (except iodine and iodide) to obtain a deep understanding of such interactions for employing them in possible applications such as sensors and surface adsorption. The ωB97XD DFT code has been utilized in this study to obtain adsorption energies in the gas phase and solvent. The energy outcomes show ...
... The effects of different chlorides and operational conditions on the distribution and speciation of six heavy metals (Pb, Zn, Cr, Cu, Mn and Ni) during sludge incineration were investigated using a simulated laboratory tubular-furnace reactor. A thermodynamic equilibrium investigation using the FactSage software was performed to compare the experimental results. The results indicate that the volat ...
aerosols; amines; ammonia; atmospheric chemistry; desorption; gas chromatography-mass spectrometry; gases; high performance liquid chromatography; infrared spectroscopy; ion exchange chromatography; molecular weight; nitric acid; nitrogen content; nitrogen oxides; ozone; photooxidation; piperazine
Abstract:
... The atmospheric degradation of piperazine was investigated using an indoor smog chamber. Experiments were carried out in the presence of nitrogen oxides (NOx), ozone or nitric acid. Piperazine reacted rapidly under all evaluated conditions: irradiated in the presence of NOx and with ozone and nitric acid in the dark. Gas phase products from the oxidation of piperazine were identified by infrared s ...
... The largest mass extinction in Earth history occurred at the end-Permian (~252millionyears ago) and is marked by a global negative carbon isotope excursion and the onset of Siberian Trap volcanism, prompting diverse hypotheses on the link between flood basalt volcanism, carbon cycle perturbations, and mass extinction. Phreatomagmatic pipes associated with Siberian Trap volcanism have been proposed ...
... Methane (CH₄) and carbon dioxide emissions from lakes are relevant for assessing the greenhouse gas output of wetlands. However, only few standardized datasets describe concentrations of these gases in lakes across different geographical regions. We studied concentrations and stable carbon isotopic composition (δ¹³C) of CH₄ and dissolved inorganic carbon (DIC) in 32 small lakes from Finland, Swede ...
aluminum; construction materials; copper; gases; liquid petroleum gas; methane; steel
Abstract:
... This article describes a method for testing the safety of construction materials with respect to mechanical sparks (spark safety). This method was tested on examples of various materials and flammable gases. Hydrogen, acetylene, petrol, methane and LPG were used as the flammable gases. Various types of steel, aluminium, and copper and aluminium alloys were used as the construction materials. On th ...
air pollution; air quality; autumn; carbon; coal; diurnal variation; gases; meteorological parameters; models; monitoring; particulates; pollutants; polycyclic aromatic hydrocarbons; power plants; seasonal variation; spring; steel; winter; Czech Republic
Abstract:
... Despite efforts to reduce air pollutants, particularly in the coal power plant and industrial sectors, the Ostrava region of the Czech Republic continues to experience episodes of high pollutant concentrations, especially during the fall and winter seasons. A short–term pilot investigation was conducted to improve understanding of air pollution sources that may be impacting the Ostrava’s air quali ...
... The current study is focused on the donor–bridge–acceptor (D–π–A) type of novel organic charge transport and non-linear optical material, 1-(4-bromophenyl)-3-(2,4,5-trimethoxyphenyl) prop-2-en-1-one (2,4,5-TMBC) to spotlight its various important properties through experimental and quantum chemical approaches. The compound 2,4,5-TMBC was synthesized via a Claisen–Schmidt condensation reaction and ...
... A series of CsAg, ReAg, CsReAg, and CsReMoAg (supported on α-Al2O3) catalysts has been prepared and evaluated for ethylene epoxidation to determine the mechanism of selectivity enhancement for high-selectivity ethylene oxide (EO) catalysts which contain high-valent Re oxyanions and other copromoters, such as MoO4²⁻. Optimal amounts of Re (as NH4ReO4) and Mo [as (NH4)2MoO4] on Cs-promoted, Ag/α-Al2 ...
... Hydrogen is one of the most promising energy carriers for the future of the world due to its tremendous capability of pollution reduction. Hydrogen utilization is free of toxic gases formation as well as carbon dioxide (CO2) emission. Hydrogen production can be implemented using a wide variety of resources including fossil fuels, nuclear energy and renewable and sustainable energy (RSE). Amongst v ...
Reda Ahmed A.; Czech H.; Schnelle-Kreis J.; Sippula O.; Orasche J.; Weggler B.; Abbaszade G.; Arteaga-Salas J. M.; Kortelainen M.; Tissari J.; Jokiniemi J.; Streibel T.; Zimmermann R.
Betula; Fagus; Picea; acetaldehyde; air flow; carbonyl compounds; combustion; emissions; emissions factor; formaldehyde; gases; mass spectrometry; softwood
Abstract:
... Gas-phase emission samples of carbonyl compounds (CCs) were collected from two modern wood combustion appliances. Multiple repetitions were conducted on masonry heater operated with three logwood species (birch, beech, and spruce) and for a pellet boiler operated by softwood pellet with normal combustion and unoptimized combustion (in which the secondary combustion air flow rate was decreased). Th ...
... Many studies tried to correlate coal pyrolysis conditions with reactivity of tars produced, but few analyzed the radical concentration of tars. This work studies pyrolysis of four coals, with carbon contents in a range of 74–82 wt %, in a fixed-bed tubular reactor at three heating rates and three N₂-purging rates. The changes in the radical concentration of tars under various conditions, such as i ...
Human rhinovirus; capsid; common cold; desorption; electrophoresis; electrospraying; encapsulation; gases; genome; ionization; mass spectrometry; molecular weight; particle size; proteins; serotypes; virion; viruses
Abstract:
... Gas-phase electrophoretic mobility molecular analysis (GEMMA) separates nanometer-sized, single-charged particles according to their electrophoretic mobility (EM) diameter after transition to the gas-phase via a nano electrospray process. Electrospraying as a soft desorption/ionization technique preserves noncovalent biospecific interactions. GEMMA is therefore well suited for the analysis of inta ...
... The analysis of the results of sorption absorbency of hard coals with respect to gases relevant in assessing the fire hazard (carbon monoxide, carbon dioxide, hydrogen, ethylene, propylene, and acetylene) was the aim of this study. Hard coals adsorb carbon dioxide and acetylene in the highest amount, and ethylene and propylene in a slightly smaller amount. The adsorption of carbon monoxide and hyd ...
aquifers; carbon; chlorofluorocarbons; gases; groundwater; helium; issues and policy; mining; mixing; models; stable isotopes; tracer techniques; tritium; trona; water management
Abstract:
... The Eocene deposits of Kazan Basin in Turkey contain a rare trona mineral which is planned to be extracted by solution mining. The complex flow dynamics and mixing mechanisms as noted from previous hydraulic and hydrochemical data need to be augmented with environmental tracer and noble gas data to develop a conceptual model of the system for the assessment of the impacts of the mining and to deve ...
... A method was optimised and evaluated for the analysis of total organic halogen (TOX) in drinking water samples. It involved adsorption of organic halogen onto activated carbon, followed by combustion of the activated carbon and adsorbed material, absorption of the resulting hydrogen halide gases in an absorbing solution, and analysis of halide ions in the solution using an on-line ion chromatograp ...
René B. Madsen; Per S. Christensen; Kasper Houlberg; Elpiniki Lappa; Anders J. Mørup; Maika Klemmer; Eva M. Olsen; Mads M. Jensen; Jacob Becker; Bo B. Iversen; Marianne Glasius
... This work provides a comprehensive characterization of the gas phase from hydrothermal liquefaction of Dried Distillers Grains with Solubles (DDGS) collected during a 24-h continuous experiment. The gas consisted mainly of CO2, CO, H2, CH4 and C2H6 accounting for 96 v/v% while further analysis by gas chromatography coupled to mass spectrometry (GC–MS) showed additionally 62 compounds of which 54 w ...
Renate Forkel; Alessandra Balzarini; Rocio Baró; Roberto Bianconi; Gabriele Curci; Pedro Jiménez-Guerrero; Marcus Hirtl; Luka Honzak; Christof Lorenz; Ulas Im; Juan L. Pérez; Guido Pirovano; Roberto San José; Paolo Tuccella; Johannes Werhahn; Rahela Žabkar
aerosols; air quality; atmospheric chemistry; cooling; droplets; gases; meteorology; pollutants; solar radiation; statistics; summer; temperature; wet deposition; wildfires; winter; Atlantic Ocean; Northern European region; Russia; Scandinavia
Abstract:
... As a contribution to phase2 of the Air Quality Model Evaluation International Initiative (AQMEII), eight different simulations for the year 2010 were performed with WRF-Chem for the European domain. The four simulations using RADM2 gas-phase chemistry and the MADE/SORGAM aerosol module are analyzed in this paper. The simulations included different degrees of aerosol–meteorology feedback, ranging f ...
... Main approaches to the determination of low-molecular-weight chemical compounds by surfaceassisted laser desorption/ionization (SALDI) are considered. Analytes are adsorbed from a gas phase on the surface of a specially prepared solid-state substrate. Then, the surface is exposed to pulse laser radiation, which leads to ionization and desorption of ions to be detected with a mass analyzer. The fac ...
... A general overview of the development of the uses of light-emitting diodes in analytical instrumentation is given. Fundamental aspects of light-emitting diodes, as far as relevant for this usage, are covered in the first part. The measurement of light intensity is also discussed, as this is an essential part of any device based on light-emitting diodes as well. In the second part, applications are ...
... The problem of fraud continues to plague the wine industry, and detecting cases where the original bottle has been refilled with an inferior vintage is especially difficult. A novel noninvasive procedure presented here relies on radiocarbon dating the so-called angel’s share: the trace amounts of ethanol and other gases that diffuse into and through the cork as bottled wine ages and matures. These ...
... Highly crystalline flake-like CuCeO2−δ composites (strCCx) with large specific surface area and developed mesoporosity were prepared using an economic and effective bio-template route. Modified starch with abundant surface carboxyl groups was adopted as the chelating agent and template for metal cations immobilization via electrostatic attraction predominately based on the process of –COO⁻⋯Cu²⁺ an ...
... We determined the number of isomers and their structures for the 18-crown-6 (18C6)–catechol host–guest complex, and examined the effect of the complex formation on the S₁ (¹ππ*) dynamics of catechol under a supersonically cooled gas phase condition and in cyclohexane solution at room temperature. In the gas phase experiment, UV–UV hole-burning spectra of the 18C6–catechol 1:1 complex indicate that ...
... Graphene frameworks can be directly formed by a rapid decomposition of common solid organic sodium salts, during which the gases simultaneously produced play a crucial role in resisting the inter-graphene stacking behaviour through in situ filling between the growing graphene films. The framework structure endows the graphene with excellent electrode performance. ...
enthalpy; gases; cobalt; aqueous solutions; aromatic compounds; copper; ionization; acetonitrile; electron transfer; dissociation; hydrogen; hydrogen bonding; antioxidant activity; metal ions
Abstract:
... DFT studies on the conformational and antioxidant properties of kanakugiol were performed to investigate factors that contribute to its conformational preferences and to elucidate its antioxidant properties and mechanisms. The antioxidant activity has been considered through the ability of kanakugiol to scavenge free radical species and through its ability to chelate metal ions. The antiradical ac ...
aerosols; air quality; atmospheric chemistry; carbon; cold; dry deposition; emissions; gases; isoprene; meteorology; mixing; model uncertainty; models; national parks; ozone; particulates; prediction; remote sensing; temperature; volatile organic compounds; wet deposition; wildfires; wind speed; Europe; Southeastern United States
Abstract:
... The Weather Research and Forecasting model with Chemistry (WRF/Chem) version 3.4.1 has been modified to include the Carbon Bond 2005 (CB05) gas-phase mechanism, the Modal for Aerosol Dynamics for Europe (MADE) and the Volatility Basis Set (VBS) approach for secondary organic aerosol (hereafter WRF/Chem-CB05-MADE/VBS), and aerosol-cloud-radiation feedbacks to improve predictions of secondary organi ...
... Microbial prospecting of hydrocarbons is based on the detection of anomalous population of hydrocarbon oxidizing bacteria in the surface soils, indicates the presence of subsurface oil and gas accumulation. The technique is based on the seepage of light hydrocarbon gases such as C₁–C₄from the oil and gas pools to the shallow surface that provide the suitable conditions for the development of highl ...
dissociation; electrophoresis; gases; hybrids; image analysis; instrumentation; ions; mass spectrometry
Abstract:
... The high chemical complexity of the lipidome is one of the major challenges in lipidomics research. Ion-mobility spectrometry (IMS), a gas-phase electrophoretic technique, makes possible the separation of ions in the gas phase according to their charge, shape, and size. IMS can be combined with mass spectrometry (MS), adding three major benefits to traditional lipidomic approaches. First, IMS–MS a ...
... The emission of N2 is important to remove excess N from lakes, ponds, and wetlands. To investigate the gas emission from water, Gao et al. (2013) developed a new method using a bubble trap device to collect gas samples from waters. However, the determination accuracy of sampling volume and gas component concentration was still debatable. In this study, the method was optimized for in situ sampling ...
World Health Organization; aerosols; carbon; climate; combustion; emissions; gases; guidelines; monsoon season; particulates; seasonal variation; summer; winter; Indian Ocean; Maldives; South Asia
Abstract:
... Urban-like plumes of gases and particulate matter originating from the South Asian region are frequently observed over the Indian Ocean, especially during the dry winter period. However, in addition to the strong sources on mainland South Asia, there are also local Maldivian emissions. The local contributions to the load of fine particulate matter (PM2.5) in the Maldivian capital Malé was assessed ...
... Anthropogenic aerosol particles exert an—quantitatively very uncertain—effective radiative forcing due to aerosol-cloud interactions via an immediate altering of cloud albedo on the one hand and via rapid adjustments by alteration of cloud processes and by changes in thermodynamic profiles on the other hand. Large variability in cloud cover and properties and the therefore low signal-to-noise rati ...
... Tail-gas reactive pyrolysis (TGRP) of biomass produces bio-oil that is lower in oxygen (∼15 wt % total) and significantly more hydrocarbon-rich than traditional bio-oils or even catalytic fast pyrolysis bio-oils. TGRP bio-oils lend themselves toward mild and inexpensive upgrading procedures. We isolated oxygen-free hydrocarbons by extraction of TGRP bio-oil distillates. Extraction proceeded by add ...
... A nonvacuum solution-based approach can potentially be used to realize low cost, roll-to-roll fabrication of chalcopyrite CuIn(S,Se)₂ (CISSe) thin film solar cells. However, most solution-based fabrication methods involve highly toxic solvents and inevitably require sulfurization and/or postselenization with hazardous H₂S/H₂Se gases. Herein, we introduce novel aqueous-based Cu–In–S and Se inks tha ...
biofuels; biomass; carbon; catalysts; chemical bonding; copper; ethylene glycol; furans; gases; glucose; hexane; hydrogenation; nickel; oxygen; sorbitol; temperature; value added
Abstract:
... Glucose is the most abundant platform molecule of biomass in nature. High value-added chemicals and liquid fuels can be obtained by selectively breaking C–C/C–O bonds and removing surplus oxygen in glucose. This article focuses on glucose hydrogenolysis over a wide variety of transition metal catalysts (Cu/C, Ni/C, Pt/C, Pd/C, Ru/C, Rh/C, Ir/C). Liquid and gas phase after reaction mainly contain t ...
... The altitudinal gradient involves changes of the partial pressures of atmospheric gases such as CO₂. This omnipresent phenomenon likely represents an evolutionary selective agent. We asked whether high altitude plant species had evolved specific response strategies to cope with high altitude pressure conditions. Plants of the high altitude species Arabis alpina and the low altitude species Arabido ...
... Although there are numerous studies suggesting hydrothermal carbonization is an environmentally advantageous process for transformation of wastes to value-added products, a systems level evaluation of the environmental impacts associated with hydrothermal carbonization and subsequent hydrochar combustion has not been conducted. The specific objectives of this work are to use a life cycle assessmen ...