Health & Environmental Research Online (HERO)


Squalane (111-01-3)


49 References Were Found:

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Particle/Gas Partitioning of Phthalates to Organic and Inorganic Airborne Particles in the Indoor Environment

Authors: Wu, Y; Eichler, CMA; Cao, J; Benning, J; Olson, A; Chen, S; Liu, C; Vejerano, EP; Marr, LC; Little, JC (2018) Environmental Science and Technology 52:3583-3590. HERO ID: 4663144

[Less] The particle/gas partition coefficient Kp is an important parameter affecting the fate and transport . . . [More] The particle/gas partition coefficient Kp is an important parameter affecting the fate and transport of indoor semivolatile organic compounds (SVOCs) and resulting human exposure. Unfortunately, experimental measurements of Kp exist almost exclusively for atmospheric polycyclic aromatic hydrocarbons, with very few studies focusing on SVOCs that occur in indoor environments. A specially designed tube chamber operating in the laminar flow regime was developed to measure Kp of the plasticizer di-2-ethylhexyl phthalate (DEHP) for one inorganic (ammonium sulfate) and two organic (oleic acid and squalane) particles. The values of Kp for the organic particles (0.23 ± 0.13 m3/μg for oleic acid and 0.11 ± 0.10 m3/μg for squalane) are an order of magnitude higher than those for the inorganic particles (0.011 ± 0.004 m3/μg), suggesting that the process by which the particles accumulate SVOCs is different. A mechanistic model based on the experimental design reveals that the presence of the particles increases the gas-phase concentration gradient in the boundary layer, resulting in enhanced mass transfer from the emission source into the air. This novel approach provides new insight into experimental designs for rapid Kp measurement and a sound basis for investigating particle-mediated mass transfer of SVOCs.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Fatty acids Profile, Squalene level and biological traits of lipids from Diospyros lotus Roots

Authors: Rauf, A; Uddin, G; Jehan, N; Bahadar, A; Arfan, M; Khan, A; Rahman, IUr; Farooq, U; Ramadan, MF (2017) HERO ID: 4999209

[Less] The aim of current investigation was to study the lipids composition and biological activities of fixed . . . [More] The aim of current investigation was to study the lipids composition and biological activities of fixed oil extracted from D. lotus root. The lipids composition of the recovered oil from D. lotus roots including fatty acid methyl esters (FAME), along with squalene were determined by gas chromatographic/mass spectrometery (GC/MS). The main constituents of oil were linoleic acid (44.9%), linoleic acid (17.8%), palmitic acid (10.8%), squalane (3%), oleic acid (2.97%), stearic acid (2.38%), and palmitic acid (2.20%). The oil was screened for antimicrobial, antioxidant, and cytotoxicity activities. D. lotus oil was subjected to various biological activities like antimicrobial, antioxidant, cytotoxicity, and insecticidal assays. D. lotus oil exhibited antimicrobial traits against Straph epidermis, Klebsiello pneumonia and Bacillus subtilis with zone of inhibition ranging from 12-15 mm. D. lotus crude oil did not show insecticidal activity against Tribolium castaneum, Rhyzopertha dominica and Callosbruchuanalis. D. lotus oil showed brine shrimp cytotoxic effect at woo mu g/ml dose with LD50 2997.99 as compared to etoposide LD50 7.4625. The degree of lethality was directly proportional to the concentration of D. lotus oil. The reults showed that D. lotus oil revealed considerable antimicrobial and antioxidant activities. The oil could be applied in different pharmaceutical and nutraceutical applications.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Influence of hydrocarbon species on its adsorption on a VSCR catalyst under simulated diesel engine operating conditions

Authors: Xi, Y; Ottinger, NA; Liu, ZG (2017) Applied Catalysis B: Environmental 217:581-590. HERO ID: 4733946

[Less] Vanadia-SCR (VSCR) is a proven technology for reducing diesel engine NOx emissions using urea hydrolysis . . . [More] Vanadia-SCR (VSCR) is a proven technology for reducing diesel engine NOx emissions using urea hydrolysis derived NH3 as a reductant. It is also known that VSCR is active for hydrocarbon (HC) oxidation. However, HC species from diesel engine exhaust may be adsorbed onto VSCR at low exhaust temperatures such as under low engine load or idle conditions. The adsorbed HC may be gradually transformed into more stable coke during engine operation. The accumulated HC or coke on VSCR can result in decreased NOx conversion efficiency due to blockage of catalyst pores and active sites. In addition, rapid oxidation of accumulated HC or coke can lead to exotherms which can thermally damage the VSCR and may lead to vanadium and tungsten release. This work investigates the fundamental adsorption characteristics of HC species on a state-of-the-art VSCR catalyst in the low temperature region. Dodecane and toluene are used as model molecules for alkane and aromatic species from unburned diesel fuel, while squalane is used as a model molecule for unburned lube oil. (C) 2017 Elsevier B.V. All rights reserved.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Predicting oligomer/polymer compatibility and the impact on nanoscale segregation in thin films

Authors: Sabattié, EFD; Tasche, J; Wilson, MR; Skoda, MWA; Hughes, A; Lindner, T; Thompson, RL (2017) Soft Matter 13:3580-3591. HERO ID: 4687157

[Less] Compatibility between oligomers and polymers was systematically assessed using differential scanning . . . [More] Compatibility between oligomers and polymers was systematically assessed using differential scanning calorimetry (DSC) and was correlated with similarity in saturation and solubility parameter. These measurements enabled validation of detailed volume of mixing calculations using Statistical Association Fluid Theory (SAFT-γ Mie) and molecular dynamics (MD) simulations, which can be used to predict behaviour beyond the experimentally accessible conditions. These simulations confirmed that squalane is somewhat more compatible with poly(isoprene), "PI" than poly(butadiene), "PB", and further enabled prediction of the temperature dependence of compatibility. Surface and interfacial segregation of a series of deuterated oligomers was quantified in rubbery polymer films: PI, PB and hydrogenated poly(isoprene) "hPI". A striking correlation was established between surface wetting transition and mixtures of low compatibility, such as oligo-dIB in PB or PI. Segregation was quantified normal to the surface by ion beam analysis and neutron reflectometry and in some cases lateral segregation was observable by AFM. While surface segregation is driven by disparity in molecular weight in highly compatible systems this trend reverses as critical point is approached, and surface segregation increases with increasing oligomer molecular weight.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Hydrocarbon biodegradation and surfactant production by acidophilic mycobacteria

Authors: Ivanova, AE; Sokolova, DSh; Kanat'eva, AYu (2016) Microbiology 85:317-324. HERO ID: 4968953

[Less] Production of biosurfactants by acidophilic mycobacteria was demonstrated in the course of aerobic degradation . . . [More] Production of biosurfactants by acidophilic mycobacteria was demonstrated in the course of aerobic degradation of hydrocarbons (n-tridecane, n-tricosane, n-hexacosane, model mixtures of D-14-D-17, D(12)aEuro'D-19, and D-9-D-21 n-alkanes, 2,2,4,4,6,8,8-heptamethylnonane, squalane, and butylcyclohexane) and their complex mixtures (hydrocarbon gas condensate, kerosene, black oil, and paraffin oil) under extremely acidic conditions (pH 2.5). When grown on hydrocarbons, the studied bacterial culture AG(S10) caused a decrease in the surface and interfacial tension of the solutions (to the lowest observed values of 26.0 and 1.3 mN/m, respectively) compared to the bacteria-free control. The rheological characteristics of the culture changed only when mycobacteria were grown on hydrocarbons. Neither the medium nor the cell-free culture liquid had the surfactant activity, which indicated formation of an endotype biosurfactant by mycobacteria. Biodegradation of n-alkanes was accompanied by an increase in cell numbers, surfactant production, and changes in the hydrophobicity of bacterial cell surface and in associated phenomena of adsorption and desorption to the hydrocarbon phase. Research on AGS10 culture liquids containing the raw biosurfactant demonstrated the preservation of its activity within a broad range of pH, temperature, and salinity.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Formation of environmentally persistent free radicals from the heterogeneous reaction of ozone and polycyclic aromatic compounds

Authors: Borrowman, CK; Zhou, S; Burrow, TE; Abbatt, JP (2016) Physical Chemistry Chemical Physics 18:205-212. HERO ID: 3075503

[Less] In the 1980s long-lived radical species were identified in cigarette tar. Since then, environmentally . . . [More] In the 1980s long-lived radical species were identified in cigarette tar. Since then, environmentally persistent free radicals (EPFRs) have been observed in ambient particulate matter, and have been generated in particulate matter generated from internal combustion engines. For the first time, we measure in situ the formation and decay of EPFRs through the heterogeneous reaction of ozone and several polycyclic aromatic compounds (PAC). Solid anthracene (ANT), pyrene (PY), benzo[a]pyrene (BAP), benzo[ghi]perylene (BGHIP), 1,4-naphthoquinone (1,4NQ), and 9,10-anthraquinone (AQ) were reacted with gas-phase ozone in a flow system placed in the active cavity of an electron paramagnetic resonance (EPR) spectrometer, and the formation of radicals was measured on the timescale of tens of minutes at ambient levels of ozone down to 30 ppb. For most substrates the net radical production is initially rapid, slows at intermediate times, and is followed by a slow decay. For oxidized solid BAP, radical signal persists for many days in the absence of ozone. To evaluate the effect of substrate phase, the solid PAHs were also dissolved in squalane, an organic oil inert to ozone, which yielded a much higher maximum radical concentration and faster radical decay when exposed to ozone. With higher mobility, reactants were apparently able to more easily diffuse and react with each other, yielding the higher radical concentrations. The EPR spectra exhibit three radicals types, two of which have been assigned to semiquinone species and one to a PAH-derived, carbon-centered radical. Although our system uses levels of PAC not typically found in the environment it is worth noting that the amounts of radical formed, on the order of 10(18) radicals per g, are comparable to those observed in ambient particulate matter.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Probing the Evaporation Dynamics of Mixed SOA/Squalane Particles Using Size-Resolved Composition and Single-Particle Measurements

Authors: Robinson, ES; Saleh, R; Donahue, NM (2015) Environmental Science and Technology 49:9724-9732. HERO ID: 3009638

[Less] An analysis of the formation and evaporation of mixed-particles containing squalane (a surrogate for . . . [More] An analysis of the formation and evaporation of mixed-particles containing squalane (a surrogate for hydrophobic primary organic aerosol, POA) and secondary organic aerosol (SOA) is presented. In these experiments, one material (D62-squalane or SOA from α-pinene + O3) was prepared first to serve as surface area for condensation of the other, forming the mixed-particles. The mixed-particles were then subjected to a heating-ramp from 22 to 44 °C. We were able to determine that (1) almost all of the SOA mass is comprised of material less volatile than D62-squalane; (2) AMS collection efficiency in these mixed-particle systems can be parametrized as a function of the relative mass fraction of the components; and (3) the vast majority of D62-squalane is able to evaporate from the mixed particles, and does so on the same time scale regardless of the order of preparation. We also performed two-population mixing experiments to directly test whether D62-squalane and SOA from α-pinene + O3 form a single solution or two separate phases. We find that these two OA types are immiscible, which informs our inference of the morphology of the mixed-particles. If the morphology is core-shell and dictated by the order of preparation, these data indicate that squalane is able to diffuse relatively quickly through the SOA shell, implying that there are no major diffusion limitations.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

OH-initiated heterogeneous oxidation of internally-mixed squalane and secondary organic aerosol

Authors: Kolesar, KR; Buffaloe, G; Wilson, KR; Cappa, CD (2014) Environmental Science and Technology 48:3196-3202. HERO ID: 2369609

[Less] Recent work has established that secondary organic aerosol (SOA) can exist as an amorphous solid, leading . . . [More] Recent work has established that secondary organic aerosol (SOA) can exist as an amorphous solid, leading to various suggestions that the addition of SOA coatings to existing particles will decrease the reactivity of those particles toward common atmospheric oxidants. Experimental evidence suggests that O3 is unable to physically diffuse through an exterior semisolid or solid layer thus inhibiting reaction with the core. The extent to which this suppression in reactivity occurs for OH has not been established, nor has this been demonstrated specifically for SOA. Here, measurements of the influence of adding a coating of α-pinene+O3 SOA onto squalane particles on the OH-initiated heterogeneous oxidation rate are reported. The chemical composition of the oxidized internally mixed particles was monitored online using a vacuum ultraviolet-aerosol mass spectrometer. Variations in the squalane oxidation rate with particle composition were quantified by measurement of the effective uptake coefficient, γeff, which is the loss rate of a species relative to the oxidant-particle collision rate. Instead of decreasing, the measured γeff increased continuously as the SOA coating thickness increased, by a factor of ∼2 for a SOA coating thickness of 42 nm (corresponding to ca. two-thirds of the particle mass). These results indicate that heterogeneous oxidation of ambient aerosol by OH radicals is not inhibited by SOA coatings, and further that condensed phase chemical pathways and rates in organic particles depend importantly on composition.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Impact factors for the degradation of engine oil causing carbonaceous deposits in the piston's grooves of Diesel engines

Authors: Diaby, M; Singhal, P; Ousmane, M; Sablier, M; Le Negrate, A; El Fassi, M; Zymla, V (2013) Fuel 107 (Apr 22:90-101. HERO ID: 4968783

[Less] This study was conducted to better understand the processes of carbonaceous deposits formation in the . . . [More] This study was conducted to better understand the processes of carbonaceous deposits formation in the piston grooves of direct injection Diesel engines. An experimental investigation of parameters affecting the engine oil degradation in the first groove of a Diesel engine was carried out to shed light on the formation of these carbonaceous deposits. A dedicated reactor was designed to reproduce the parameters that exist in the first groove of a Diesel engine used under exhaust gas recirculation conditions, and squalane was used to model the lubricant. The relationship between oil degradation and environmental conditions (temperature, pressure, time, oxygen content and components of the gas in the groove) was clarified by characterizing the degradation levels of the squalane molecule. A general mechanism was proposed to explain the formation of carbon deposits in the first piston grooves of Diesel engines depending on the surrounding atmosphere. The influence of pressure on degradation conditions usually investigated under atmospheric conditions was proposed for the first time to understand processes responsible for carbonaceous deposit formation.

Technical Report
Technical Report

2,6,10,15,19,23-hexamethyltetracosane: short-term toxicity to aquatic invertebrates

Author: ECHA (2013) HERO ID: 5016717