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air quality; alkanes; climate change; coal; combustion; dust; environment; human health; organic carbon; particulates; uncertainty
Abstract:
... Carbonaceous substances in industrial emissions are harmful to human health, air quality, and climate change. Owing to the existence of various fuel types and different technological processes, the characterization of carbonaceous substances from industrial emissions varies significantly, which causes a large uncertainty in source apportionment. Therefore, nine typical industrial sources were sele ...
... The preparation of supramolecular cyclodextrin (CD) assemblies and control of their assembly mode through guest inclusion in CD cavities have been actively studied. Contrarily, there are limited reports on the control of the assembly mode of guest-free CD molecules by external stimuli. Herein, we report the use of 2-O-methylated β-cyclodextrin (2-Me-β-CD) as an effective building block in fabricat ...
... Present study demonstrates a two-stage integrated process for production of hydrocarbon oil designated as ALGLIQOL, with potential to be utilized as liquid transportation fuel. Stage-I involves in-situ catalytic hydrothermal liquefaction (HTL) of microalgae biomass to produce biocrude oil and stage-II involves distillation of biocrude to hydrocarbon oil. A strategic attempt has been implemented to ...
... Self-assembly of surfactants in aqueous solution can form a variety of aggregate structures, among which worm-like micelles (WLMs) have attracted much attention due to their excellent viscoelasticity. The addition of oil often leads to a decrease in the viscosity of WLMs, which is closely related to the location of oil dissolution within the WLMs. Whether oil could induce a viscosity increase in W ...
... Poly(lactic acid) (PLA), a well-known environmentally friendly polymer, however, due to its brittleness and poor antibacterial properties, it is restricted in several aspects. In this study, alkyl thiol-grafted Ag nanoparticle (NP)-decorated cellulose nanocrystals (ATₓ-Ag-CNCs) were obtained by modifying Ag NP-decorated CNCs (Ag-CNCs) with 1-decanethiol, 1-tetradecanethiol and 1-octadecanethiol, a ...
... Eremanthus erythropappus (DC) McLeisch (Asteraceae), commonly known as “candeia”, is a native species of Minas Gerais state, Brazil, frequently used in medicine as an anti-inflammatory and antimicrobial agent. Eremanthus erythropappus hosts six different gall morphotypes, whose associated inducers manipulate plant cells and tissues and stimulate the neo-synthesis, maintenance, or inhibition of bot ...
... This article presents the first experimental data on the ability of microbial communities from sediments of the Gorevoy Utes natural oil seep to degrade petroleum hydrocarbons under anaerobic conditions. Like in marine ecosystems associated with oil discharge, available electron acceptors, in particular sulfate ions, affect the composition of the microbial community and the degree of hydrocarbon c ...
aldehydes; alkanes; cured meats; food analysis; gas chromatography-mass spectrometry; ham; meat quality; octenol; odor compounds; olfactometry; pyrazines; sulfides; China
Abstract:
... Chinese dry-cured hams have become increasingly appreciated by consumers because of their unique flavor characteristics. In this study, the volatile compounds of four Yunnan dry-cured hams (Xuanwei, Nuodeng, Sanchuan, and Saba) were characterized by monolithic material sorptive extraction (MMSE) and GC-MS. A total of 66 volatile compounds were identified, of which aldehydes and alkanes were the mo ...
alkanes; chemistry; equations; models; process design
Abstract:
... SAFT-VR Mie is an established equation of state that offers excellent holistic descriptions of fluid behavior. However, the model does not account for the long-wavelength density fluctuations encountered in the critical region and can therefore not describe this region accurately. To this end, SAFT-VR Mie is treated with renormalization corrections, yielding SAFT-VR Mie + RG. This procedure is bas ...
alkanes; carbon cycle; environment; fossil fuels; hybrids; industrialization; oils; rivers; sediments; total organic carbon; transportation; urbanization; China
Abstract:
... Sedimentary organic matter (SOM) plays an important role in the transportation and transformation of various pollutants and the carbon cycle in aquatic and terrestrial ecosystems, especially for seagoing rivers. However, few studies have focused on the sources and factors of SOM in rivers under the significant pressure of high urbanization and industrialization. In this study, we adopted the molec ...
... PURPOSE: Understanding fluxes of soil organic carbon (OC) from the terrestrial to aquatic environments is crucial to evaluate their importance within the global carbon cycle. Sediment fingerprinting (SF) is increasingly used to identify land use-specific sources of OC, and, while this approach estimates the relative contribution of different sources to OC load in waterways, the high degree of spat ...
... With the crude oil exploration activities in the Shanbei oilfield of China, the risk of soil contamination with crude oil spills has become a major concern. This study aimed at assessing the bioremediation potential of the petroleum polluted soils by investigating the expression of key functional genes decoding alkane and aromatic component degradation using an array of primers and real-time quant ...
... It is well known that the electrical conductance of molecular junctions in the tunneling regime varies exponentially with the length of the molecular backbone. This behavior is strongly influenced by anchoring groups, which connect the molecular backbone to the electrodes and locate the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) resonances with respect ...
... Here, we combine an advanced synthesis of two-dimensional (2D) materials (MoSe₂) having well-defined atomic edge configurations with ab initio and atomistic molecular dynamics (MD) simulations to study how atomic edges interact with polyethylene (HDPE) chains in a dilute solution assembly process. Our results reveal that Mo-terminated zigzag (Mo-ZZ) edges act as preferred nucleation sites and stro ...
... Hudson Bay is a small arctic inland shelf sea which receives large amounts of freshwater from riverine discharges, with marine flow from the north and the Atlantic. A warming climate has resulted in an expanded open water season which will result in an increase in shipping of fuel oil and petroleum to communities and mines on the western shore, increasing the risk of hydrocarbon releases. To evalu ...
alkanes; byproducts; physical chemistry; spectroscopy; temperature
Abstract:
... Although long-chain aliphatic hydrocarbons are documented in meteorites, their origin is poorly understood. A key question is whether they are pristine or a byproduct of terrestrial alteration? To understand if these long-chain hydrocarbons are indigenous, it will be important to explore their thermodynamic and mechanical stability at conditions experienced by extraterrestrial objects during atmos ...
... Volatile organic compounds (VOCs) are generated in different commodities through various biosynthetic pathways. They act as biomarkers for different infections and metabolisms and can be instrumental in the development of biosensors for monitoring the health of stored horticultural commodities. Healthy onions and samples infected with Pectobacter Erwinia carotovora were stored at different conditi ...
Iuliana Vasiliev; Marcel T.J. van der Meer; Marius Stoica; Wout Krijgsman; Gert-Jan Reichart; Sergei Lazarev; Geanina A. Butiseacă; Eva M. Niedermeyer; Elmira Aliyeva; Christian G.C. van Baak; Andreas Mulch
... Landlocked basins like the Caspian Sea are highly sensitive to changes in their hydrological budget, especially at times of disconnection from the global ocean. Here, we reconstruct the Pliocene to Pleistocene palaeohydrological and palaeoenvironmental changes occurring in the South Caspian Basin between ~3.6 and ~ 1.9 Ma, using compound-specific hydrogen isotope (δ²H) data on long chain n-alkanes ...
... Efficient biosurfactant producers with hydrocarbon degradation capability and harsh environment adaptability are precious bioresources for microbial enhanced oil recovery and petroleum-related bioremediation. In this study, a novel facultative-halophilic strain Bacillus sp. XT-2 was isolated and shown to degrade long-chain hydrocarbons along with lipopeptide biosurfactants production. The biosurfa ...
... Photoproducts can be formed rapidly in the initial phase of a marine oil spill. However, their toxicity is not well understood. In this study, oil was irradiated, chemically characterized, and tested for toxicity in three copepod species (Acartia tonsa, Temora longicornis, and Calanus finmarchicus). Irradiation led to a depletion of polycyclic aromatic hydrocarbons (PAHs) and n-alkanes in oil resi ...
... Thirteen Australian oils and one condensate, covering oil reservoir ages from Mesoproterozoic to Early Cretaceous, show monoalkene contents varying from 0.01 to 22.3 wt% of the whole liquid. Radiolysis of saturated hydrocarbons is the most likely process leading to oils with high alkene contents. The major radiolytic component is an unresolved complex mixture (UCM). The bulk of the resolved alkene ...
... Percolation of water through oily sludge during storage and handling of the sludge can cause soil and groundwater contamination. In this study, oily sludge from a refinery was equilibrated with water to obtain the water-soluble fraction (WSF) of oily sludge. The WSF had dissolved organic carbon (DOC) of 166 mg/L. Human cell line-based toxicity assay revealed IC₅₀ of 41 mg/L indicating its toxic na ...
... Flavor characteristics of raw shrimp, high-salt and low-salt shrimp paste were evaluated and compared by sensory analysis, headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). In addition, aroma profiles and aroma-active compounds in these three samples were analyzed by solvent-assisted flavor evaporat ...
... In this study, two biosurfactant producing Pseudomonas aeruginosa sp. were isolated from motor oil contaminated soil for crude oil, alkane and PAH degradation studies. Metagenomics analysis identified as proteobacteria phyla was the dominant. Isolated two bacterial species were well grown in mineral salt medium with 1% of crude oil, alkanes (dotriacontane and tetratetracontane) and PAH (pyrene, be ...
air quality; alkanes; climate change; coal; combustion efficiency; environment; fuel combustion; heating systems; human health; organic carbon
Abstract:
... Residential solid fuel emissions are among the most important sources of carbonaceous substances that exert harmful effects on air quality, human health and climate change. Considering the constantly updated emission reduction policies for residential solid fuel combustion in the Beijing-Tianjin-Hebei (BTH) region, the emission data for the source should updated in a timely manner. Testing was per ...
... An intensive field campaign was carried out in Hefei, a city in the Yangtze River Delta in eastern China, in the summer of 2020 to examine the composition and sources of organic aerosols (OA). Time-resolved filter samples were collected and quantified to obtain the concentrations for organic functional groups (OFGs), including alkane, hydroxyl, carboxylic acid, non-acid carbonyl, amine, and aromat ...
... The International Marine Organization 2020 Global Sulfur Cap requires ships to burn fuels with <0.50% S and some countries require <0.10% S in certain Sulfur Emission Control Areas but little is known about these new types of fuels. Using both traditional GC–MS and more advanced chromatographic and mass spectrometry techniques, plus stable isotopic, δ¹³C and δ²H, analyses of pristane, phytane and ...
accidents; alkanes; case studies; combustion; condensates; environment; evaporation; flammability; fuel oils; fume hoods; soot; tankers; volatilization; East China Sea
Abstract:
... The condensate spill accident from the Sanchi oil tanker collision in the East China Sea is unique in world history. To date, the spilled and burnt amounts of condensate remain unknown. The present study demonstrates the chemical fingerprints of a surrogate condensate (SC) from the same source, and of the carried heavy fuel oil (HFO) of the Sanchi accident. The evaporative features of the condensa ...
... The chemical profiles of PM₂.₅ emitted from a non-road diesel generator, wood burning and cooking activities including chicken and beef charcoal grilling and general cooking activities were determined. The characterization included the carbonaceous fraction (OC/EC), water-soluble ions, elements, and organic species comprising n-alkanes, polycyclic aromatic hydrocarbons, carboxylic acids, levogluco ...
... One of the more important classes of potentially toxic indoor air chemicals are the Volatile Organic Compounds (VOCs). However, due to a limited understanding of the relationships between indoor concentrations of individual VOCs and health outcomes, there are currently no universal health-based guideline values for VOCs within Europe including the UK. In this study, a systematic search was conduct ...
adsorption; alkanes; chemical species; density functional theory; drugs; enantiomers; fluorescence; gas chromatography; hydrogen bonding; pollutants; pollution control; standard deviation
Abstract:
... Hydrogen-bonded organic frameworks (HOFs) are two dimensional (2D) or three dimensional (3D) porous crystalline materials constructed by Hydrogen bond interaction. In recent years, a variety of functional HOF materials have been successfully synthesized and used in structural identification, environmental pollutant removal, chiral resolution, drug delivery, fluorescence sensing, etc. Here, we firs ...
... Irregular hemorrhagic traumas always threaten the health of patients due to uncontrollable bleeding and wound infections. The traditional hemostatic materials show dissatisfactory hemostatic efficiency and antibacterial activity in solving these potential bleeding dangers. Herein, we proposed a kind of composites based on flexible wood membrane (FWM) loaded with chitosan/alginate derivative for ac ...
... Chlorinated paraffins (CPs) are high production volume chemicals currently produced and used in higher quantities than any other medium-size polyhalogenated compound (class). In addition, the composition of industrial CP mixtures is highly complex and poorly understood. In this article, we searched in the literature for the beginning of the chlorination of alkanes and how this substance class deve ...
Beauveria bassiana; Calliptamus; Locusta migratoria; Metarhizium robertsii; alkanes; conidia; fungi; gas chromatography; germination; lipid composition; lipids; mass spectrometry; migratory behavior
Abstract:
... Cuticular lipids protect insects from desiccation and may determine resistance to fungal pathogens. Nonetheless, the trade-off between these lipid functions is still poorly understood. The migratory locust Locusta migratoria and the Italian locust Calliptamus italicus have dissimilar hygrothermal preferences: L. migratoria inhabits areas near water bodies with a reed bed, and C. italicus exploits ...
Brassica oleracea var. alboglabra; alkanes; cabbage; carbon; chemical composition; cutin; hydrophobicity; petioles; plant cuticle; transpiration
Abstract:
... Plant cuticle as hydrophobic barrier covers almost all aerial plant organs. Herein the cuticular chemical components and the transpiration of various organs of Chinese flowering cabbage (CFC) and Chinese kale (CK) were comprehensively characterized. Numerous species‐ and organ‐specific differences in morphological, chemical, and physiological levels were found. The various organs were relatively s ...
... Pseudomonas chloritidismutans is a facultative anaerobic and chlorate-reducing bacterium. Many strains of chlorate-reducing P. chloritidismutans are suitable for biotechnological applications because they can undergo ammonia assimilation, aerobic denitrification, phosphorus removal, and pollutant degradation (Hou et al. 2021; Wolterink et al. 2002). Chlorate-reducing bacteria were mostly isolated ...
... To reflect the changes in pollution sources and evaluate the control efficiency more reasonably, seven groups of PM₂.₅-bound primary organic aerosol (POA) tracers indicative of pollution sources in urban Shanghai were analyzed before (BP), during (CIIE) and after (AP) the second China International Import Expo (CIIE, October 28–November 17, 2019). Combined with meteorological conditions, correlati ...
... Nature conservation is currently shaping many terrestrial ecosystems in Africa. This is particularly evident in Sub-Saharan Africa (SSA), where conservation is intended to recover wildlife populations, with special focus on elephants. Rising numbers of elephants induce woody biomass losses but increase soil organic carbon (SOC) stocks from decaying wood and dung. We hypothesized that these increas ...
algorithms; alkanes; carbon; comprehensive two-dimensional gas chromatography; distillation; mass spectrometry; nuclear magnetic resonance spectroscopy; viscosity
Abstract:
... For the purpose of formulating surrogate fuels for two lower freezing point diesels, namely −35# diesel and − 50# diesel, two-dimensional gas chromatography with time-of-flight mass spectrometry (GC × GC–TOFMS) was utilized to analyze their components in detail. And nuclear magnetic resonance (NMR) spectroscopy was used to obtain the composition of functional groups in hydrocarbons, which were cla ...
... This study is focused on producing biofuels from waste oils via a tandem vapor-phase hydrotreating process in a pressurized two-stage fixed bed reactor over a bifunctional Ni/Al₂O₃-SiO₂ catalyst under 0.25 MPa H₂. A 100% hydrodeoxygenation efficiency both in liquid and gas products was observed, yielding 83.9 wt% C₅-C₁₉ n-alkanes which corresponds to a 7.4-fold increase compared with that obtained ...
... Paraffin wax deposition has long been a vexing problem in industry. Especially, in offshore oil production, paraffin wax deposits and clogs pipes and containers because of low temperature, causing severe economic loss. It has been known that the crystallization of n-alkanes mainly causes the deposition of paraffin wax, which is necessary to understand the mechanism of the crystallization behavior ...
alkanes; crystallization; heat; molecular weight; polyesters; temperature
Abstract:
... Poly(ethylene tridecanodiate), also known as poly(ethylene brassylate) (PEB), is a short–long aliphatic polyester obtained from a renewable source. Cooled from the melt by differential scanning calorimetry or by fast scanning calorimetry, PEBs in a range of molar mass between 27000 and 188000 Da display single crystallization exotherms. On heating, PEBs exhibit two major melt-recrystallization eve ...
... 1. Fruit flies in the genus Rhagoletis are a model for ecological speciation via sympatric host plant shifting. Rhagoletis mate on or near the fruit of their respective host plants, generating premating reproductive isolation between taxa specialised on different hosts. However, non‐host‐related premating isolation has been observed between some Rhagoletis species associated with morphological dif ...
... Holy basil (Ocimum sanctum Linn) or known also as “kemangi” in Indonesia is a plant commonly used as a herb in Asian countries. It is also medicinal with antipyretic, anti-inflammatory, anti-cancer, and neuroprotective properties. This dataset article provides broad screening of the phytochemical component of Ocimum sanctum ethanolic extract (EEOS) as well as a secondary metabolite profile of EEOS ...
Holocene epoch; air; alkanes; basins; biomarkers; coasts; monsoon season; organic matter; palaeogeography; paleoclimatology; paleoecology; primary productivity; provenance; river deltas; sediments; watersheds; Republic of the Congo
Abstract:
... A 19.5-m long Holocene sediment core (MZ-1) was retrieved from Manzala lagoon coast, the depocenter of the Nile Delta. AMS-dating shows the complete Holocene strata of MZ-1, mostly consisting of lagoon muds. The high-resolution dated geochemical elements (major and trace) and bio-markers (n-alkanes) of MZ-1 serve as effective hydroclimate proxies that oscillated during the Africa Humid Period (AHP ...
... BACKGROUND: Accumulation of industrial dyes in wastewater creates not only environmental problems, but also medical and aesthetic problems. Removal of synthetic dyes from contaminated hot textile industrial discharge is a fundamental issue. Herein, the microbial decolorization of azo dyes amaranth RI and fast red E was studied. The decolorization process was studied in terms of various physicochem ...
... 6:2 fluorotelomer sulfonic acid (6:2 FTSA) is one per- and poly-fluoroalkyl substances commonly detected in the environment. While biotransformation of 6:2 FTSA has been reported, factors affecting desulfonation and defluorination of 6:2 FTSA remain poorly understood. This study elucidated the effects of carbon and sulfur sources on the gene expression of Rhodococcus jostii RHA1 which is responsib ...
alkanes; biomarkers; carbon; molecular weight; petroleum; Malaysia; Middle East
Abstract:
... In this study, levels and sources of aliphatic hydrocarbons and hopanes in surface sediments collected from rivers and estuaries of Peninsular Malaysia were assessed. The concentrations of total n-alkanes ranged from 21.19 to 364.54, and the concentrations of hopanes ranged from 0.23 to 2.45 mg kg⁻¹ dry weight. Evaluation of aliphatic diagnostic indices including Carbon Preference Index (CPI), low ...
... The Altai Mountains are located at the junction of Asia and Europe and pathways linking East Asian climate with the Arctic and North Atlantic. Here, we report a record of n-alkanes from the sediments of Shuanghu Lake in the Altai Mountains. In this forested region, the vegetation is dominated by C₃ plants and the long-chain n-alkanes (C29–C31) in the lake sediments are predominantly derived from l ...
... Indoor dust is an important medium to evaluate human exposure to emerging organic contaminants. The principal aim of this study was to determine overall status of organic micropollutants (OMPs) of indoor dust in Kuala Lumpur, Malaysia and assess their corresponding health risks. One hundred thirty-three OMPs, ascribed to 13 chemical groups, were screened by Automated Identification and Quantificat ...