Role Of Acetone Research Articles

Separation of Re(VII) from aqueous solution by acetone-enhanced photoreduction: an insight into the role of acetone

Efficient separation of rhenium (Re) from aqueous solution is pivotal in the resource recovery, and suitable to simulate the elimination of radiotoxic technetium (Tc) due to their similar properties. In this work, we achieved a high Re(VII) separation ratio of 95.2% within 30 min from aqueous solution via an acetone-enhanced photoreduction method, in which soluble ReO4− was reduced to insoluble ReOx and Re(0) in the presence of acetone and isopropanol. Compared with the situation in absence of acetone, acetone absorbed most of the UV energy, and the produced triplet acetone could abstract Hα atoms from isopropanol to form more strongly reductive ketyl radicals, leading to the enhancement in photoreduction. Isopropanol was the most qualified for Re(VII) photoredction due to its low C–Hα bond energy. The addition of alkali also benefited the Re(VII) separation by eliminating produced protons, and stabilizing the intermediate Re(VI) to preventing the re-formation of Re(VII) through disproportionation of Re(VI). Furthermore, selective and effective separation of Re(VII) from simulated high level liquid waste containg Nd(III) was realized as well. This work gains an insight into the role of acetone in the enhanced Re(VII) photoreduction, which may be of great significance in developing novel approaches for hydrometallurgy and spent nuclear fuel reprocessing.

The role of acetone in the [omim][BF4]-mediated adverse effects on tissues of mussels, human lymphocytes and the fruit fly Drosophila melanogaster

The present study investigated [omim][BF4]-mediated adverse effects on biological models widely used in toxicological studies. Specifically, mussels of the genus Mytilus, human lymphocytes and fruit flies of the species Drosophila melanogaster, were exposed to [omim][BF4] at concentrations ranging from micro- to milligrams per liter, with or without the presence of acetone as a carrier solvent and thereafter [omim][BF4]-mediated adverse effects were analyzed appropriately (stress indices, such as lipid peroxidation byproducts, acetylcholinesterase/AChE activity and micronucleus/MN formation frequency, in mussel gills, Cytokinesis Block Micronucleus/CBMN assay and SMART test in human lymphocytes and fruit flies respectively). LC–MS–TOF analysis was also performed for elucidating [omim][BF4] mode of action in the presence of the carrier solvent. The results showed the toxic potential of [omim][BF4], as well as acetone’s ability to attenuate [omim][BF4]-mediated toxicity in almost all cases, probably due to the significant effect of acetone on the hydrophilic-lipophilic character and the viscosity of [omim][BF4], as well as its interaction and permeability on the cell membranes. The slight involvement of acetone in the attenuation of [omim][BF4]-mediated genotoxic effects on D. melanogaster could be due to species feeding experimental conditions, thus favoring the induction of antioxidant defense system against the [omim][BF4]-mediated effects in all cases.

Role of Acetone in the Formation of Highly Dispersed Cationic Polystyrene Nanoparticles

Abstract A modified emulsion polymerisation synthesis route for preparing highly dispersed cationic polystyrene (PS) nanoparticles is reported. The combined use of 2,2′-azobis[2-(2-imidazolin- 2-yl)propane] di-hydrochloride (VA-044) as the initiator and acetone/water as the solvent medium afforded successful synthesis of cationic PS particles as small as 31 nm in diameter. A formation mechanism for the preparation of PS nanoparticles was proposed, whereby the occurrence of rapid acetone diffusion caused spontaneous rupture of emulsion droplets into smaller droplets. Additionally, acetone helped to reduce the surface tension and increase the solubility of styrene, thus inhibiting aggregation and coagulation among the particles. In contrast, VA-044 initiator could effectively regulate the stability of the PS nanoparticles including both the surface charge and size. Other reaction parameters i.e. VA-044 concentration and reaction time were examined to establish the optimum polymerisation conditions.

Investigation of toxic effects of imidazolium ionic liquids, [bmim][BF4] and [omim][BF4], on marine mussel Mytilus galloprovincialis with or without the presence of conventional solvents, such as acetone

This study investigated the cytotoxic, oxidative and genotoxic effects of two commonly used imidazolium ionic liquids (ILs), [bmim][BF4] (1-butyl-3-methylimidazolium) and [omim][BF4] (1-methyl-3-octylimidazolium tetrafluoroborate), on the marine mussel Mytilus galloprovincialis, as well as whether acetone could mediate their toxic profile. In this context, mussels were firstly exposed to different concentrations of [bmim][BF4] or [omim][BF4], with or without the presence of acetone (at a final concentration of 0.06% v/v), for a period of 96h, in order to determine the concentration that causes 50% mussel mortality (LC50 values) in each case. Thereafter, mussels were exposed to sub- and non-lethal concentrations of ILs for investigating their ability to cause lysosomal membrane impairment (with the use of neutral red retention assay/NRRT), superoxide anion and lipid peroxidation byproduct (malondialdehyde/MDA) formation, as well as DNA damage and formation of nuclear abnormalities in hemocytes. The results showed that [omim][BF4] was more toxic than [bmim][BF4] in all cases, while the presence of acetone resulted in a slight attenuation of its toxicity. The different toxic behavior of ILs was further revealed by the significantly lower levels of NRRT values observed in [omim][BF4]-treated mussels, compared to those occurring in [bmim][BF4] in all cases. Similarly, [bmim][BF4]-mediated oxidative and genotoxic effects were observed only in the highest concentration tested (10mgL−1), while [omim][BF4]-mediated effects were enhanced at lower concentrations (0.01–0.05mgL−1). Overall, the present study showed that [bmim][BF4] and [omim][BF4] could induce not only lethal but also nonlethal effects on mussel M. galloprovincialis. The extent of [bmim][BF4] and/or [omim][BF4]-mediated effects could be ascribed to the length of each IL alkyl chain, as well as to their lipophilicity. Moreover, the role of acetone on the obtained toxic effects of the specific ILs was reported for the first time, giving evidence for its interaction with the ILs and the modulation of their toxicity.

Toxicity of two imidazolium ionic liquids, [bmim][BF4] and [omim][BF4], to standard aquatic test organisms: Role of acetone in the induced toxicity

The main goal of this study was to investigate the toxicity of the imidazolium-based ionic liquids (ILs), [bmim][BF4] (1-butyl-3-methylimidazolium tetrafluoroborate) and [omim][BF4] (1-octyl-3-methylimidazolium tetrafluoroborate), in battery of standard aquatic toxicity test organisms. Specifically, exposure of the algae Scenedesmus rubescens, crustaceans Thamnocephalus platyurus and Artemia franciscana, rotifers Brachionus calyciflorus and Brachionus plicatilis and bivalve Mytilus galloprovincialis to different concentrations of [bmim][BF4], [omim][BF4] and/or a binary mixture of [bmim][BF4]–[omim][BF4] (1:1) with or without acetone (carrier solvent), revealed that solvent can differentially mediate ILs’ toxic profile. Acetone's ability to differentially affect ILs' cation's alkyl chain length, as well as the hydrolysis of [BF4−] anions was evident. Given that the toxic potency of the tested ILs seemed to be equal or even higher (in some cases) than those of conventional organic solvents, the present study revealed that the characterization of imidazolium-based ILs as “green solvents” should not be generalized, at least in case of their natural occurrence in mixtures with organic solvents, such as acetone.

An Alternative Mechanistic Paradigm for the β‐Z Hydrosilylation of Terminal Alkynes: The Role of Acetone as a Silane Shuttle

The β-Z selectivity in the hydrosilylation of terminal alkynes has been hitherto explained by introduction of isomerisation steps in classical mechanisms. DFT calculations and experimental observations on the system [M(I)2{κ-C,C,O,O-(bis-NHC)}]BF4 (M=Ir (3a), Rh (3b); bis-NHC=methylenebis(N-2-methoxyethyl)imidazole-2-ylidene) support a new mechanism, alternative to classical postulations, based on an outer-sphere model. Heterolytic splitting of the silane molecule by the metal centre and acetone (solvent) affords a metal hydride and the oxocarbenium ion [R3Si-O(CH3)2](+), which reacts with the corresponding alkyne in solution to give the silylation product [R3Si-CH=C-R](+). Thus, acetone acts as a silane shuttle by transferring the silyl moiety from the silane to the alkyne. Finally, nucleophilic attack of the hydrido ligand over [R3Si-CH=C-R](+) affords selectively the β-(Z)-vinylsilane. The β-Z selectivity is explained on the grounds of the steric interaction between the silyl moiety and the ligand system resulting from the geometry of the approach that leads to β-(E)-vinylsilanes.

The effect of guest molecules on the conformation and molecular assembly of the fac-[RuCl3(NO)(dppb)] complex

This paper describes the occurrence of two crystalline solvate forms of the nitrosyl ruthenium complex fac-[RuCl3(NO)(dppb)] (dppb=1,4-bis(diphenylphosphino)butane), and the role of acetone and chloroform inclusions on molecular conformations and molecular assemblies. These two crystal forms were identified by X-ray diffraction and infrared spectroscopy, and compared with the known crystal structure of the complex, without the solvent. Using the FT-IR technique, it was possible to assign the bands characteristics of the nitrosyl stretching and the solvents. An interesting structural aspect occurring in both solvate forms is that the solvent inclusion modifies the molecular conformation of the dppb ligand and the molecular assembly. Due to the similar total volume of guest solvents, the unit cell parameters are similar, resulting in an isostructural arrangement with small differences in the intermolecular interactions, with caged guest solvents, that interact with the complex by hydrogen bonds.

Spherical Rh17S15@C and Rh@C core–shell nanocomposites: Synthesis, growth mechanism and methanol tolerance in oxygen reduction reaction

Core–shell structured Rh17S15@C and Rh@C nanocomposites have been synthesized by a one-step solvothermal method from the reaction of Rh6(CO)16 with or without sulfur in acetone. The resultant Rh17S15@C composite consists of spherical Rh17S15 cores with homogeneous diameter of ∼20nm and amorphous carbon shell of 11–15nm in thickness. The sulfide core and the carbon shell are tunable in size through adjusting the acetone concentration or altering the solvothermal reaction time respectively. N2 adsorption–desorption measurement suggests that the composite is porous with relative high surface area over 180m2g−1. In the absence of sulfur, Rh@C composite was prepared by the same method. This composite is of similar core–shell structure as that of the sulfur-contained product with metallic Rh nanospheres as cores. The role of acetone in the preparation of those composites was found to be triplex. As solvent it provides the solvothermal environment, and most importantly it participates in the formation of the spherical cores and is the source of the carbon shell. Cyclic voltammetry and rotating disk electrode measurements were employed to evaluate the electrocatalytic activity of these composites for oxygen reduction reaction in the presence and absence of methanol.

Large-surface mesoporous TiO2 nanoparticles: Synthesis, growth and photocatalytic performance

This study demonstrates a facile and effective method to generate mono-dispersed titanium dioxide spheres at ambient conditions. The size of the colloids can be controlled from 60 to 500nm by optimizing experimental parameters (e.g., concentration, time, and temperature). Anatase TiO2 can be obtained through titanium glycolate colloids generated in acetone via two ways: water boiling approach and calcination at a high temperature of 500°C. Particle characteristics (shape, size, and size distribution) were measured by advanced techniques, including transmission electron microscope (TEM), thermo-gravimetric analysis (TGA), UV/Vis absorption spectrum, nitrogen gas adsorption and desorption isotherms Brunauer–Emmett–Teller (BET) surface area measurement, and X-ray diffraction technique (XRD). The possible mechanism of nucleation and growth of such colloids was discussed. The role of acetone in the formation and growth of titanium glycolate colloids was also investigated by Fourier transform infrared (FT-IR) spectroscopy. Finally, the photocatalysis performance of such anatase TiO2 particles was tested and proved to be efficient in degradation of organic dyes (e.g., phenolphthalein and methly orange).

Transformation of tetrabromobisphenol A in the presence of different solvents and metals

Solvent-based separation method is presumably an efficient and environmentally beneficial approach for elimination of brominated flame retardants (BFRs) from waste electrical and electronic equipment (WEEE). The overall goal of this study was to evaluate possible effects of organic solvent on the behavior of BFRs during solvent-based processing of WEEE. We initiated a set of batch experiments for examining the rates and possible pathways of transformation of a representative BFR (tetrabromobisphenol A, TBBPA) using acetone, toluene, and methanol as the solvents. Our results showed that toluene and methanol had no effect on the transformation of TBBPA, but approximately 20% of TBBPA (100mgL−1) was transformed by acetone within 2h at 50°C. Analysis of the products with GC–MS showed that two high-molecular-weight products (MW=586) were major products of the transformation reactions. The role of acetone as a reactant in the transformation of TBBPA was further validated with dueterated acetone. In addition, the effects of co-existing metals in WEEE (i.e., Zn, Cu, and Ni) on the transformation of TBBPA in the solvent systems were investigated. These metals tested were found to greatly enhance the rates of TBBPA transformation. The metal facilitated solvent reactions with TBBPA may lower the extractability of TBBPA by formation of larger and less soluble products, hence potentially increasing the cost for separating the chemical from WEEE.

Rapid Synthesis of Gold Nanorods Using a One-Step Photochemical Strategy

Rapid synthesis of gold nanorods of controlled dimensions is one of the desired aspects of nanotechnology as a result of the potential of these nanomaterials for biomedical applications. The synthesis of gold nanorods has been achieved using a photoinitiator as an instant source of ketyl radicals, which allows the synthesis of gold nanorods in minutes. This is the first report providing a one-step synthesis of nanorods of controlled dimensions in 20-30 min using photoinitiator I-2959 as a source of ketyl radicals. Furthermore, the role of UV intensity, the concentration of silver ions, and the presence of cosolvents and a cosurfactant have been studied in detail in an effort to produce nanorods with controlled dimensions in higher yields. The role of acetone in nanorod synthesis has been explored in detail, and it has been demonstrated that, for the photochemical synthesis of nanorods using a photoinitiator, acetone is not a critical component and can be replaced by other water-miscible solvents, thus the successful synthesis of nanorods in tetrahydrofuran (THF) has been demonstrated. It has also been found that a cosurfactant and an organic solvent are not required for the synthesis of nanorods; however, their presence is found to improve the monodispersity of nanorod samples, in addition to providing a higher yield.

Effects of Intraruminal versus Intravenous Infusions of Acetone on the Ruminating and Masticating Behavior of Goats

Acetone, which is produced from butyric acid when it passes through the rumen wall, was infused into the rumen and jugular veins of three female goats to investigate the role of acetone in ruminating and masticating behavior. The ruminating behavior, as measured by the number of boli and the ruminating time, decreased (p<0.05) with intraruminal acetone infusion. However, the ruminating behavior did not change significantly in response to intravenous acetone infusion. Feed intake significantly decreased with intraruminal acetone infusion, but not with intravenous acetone infusion. The concentrations of acetone in the plasma increased significantly (p<0.05) with both acetone infusion regions. Ruminal fluid acetone, and isopropyl alcohol (IPA), which is one of the ketone bodies, produced from acetone by bacterial action in rumen, concentrations were significantly increased (p<0.05) with both acetone infusion regions. These results suggest that the chemoreceptors sensitive to acetone are more likely to be in the rumen epithelium, portal system, or liver, where they can respond to acetone levels. (Asian-Aust. J. Anim. Sci. 2003. Vol 16, No. 2 : 198-203)

Acetone and PAN in the upper troposphere: impact on ozone production from aircraft emissions

The role of acetone and PAN in the chemistry of the upper troposphere has been investigated with a time-dependent photochemical box model. The results show that acetone strongly enhances aircraft-related ozone production, as exemplified in this study over North Atlantic during summer. For typical flight corridor conditions, the inclusion of about 1 nmol mol −1 acetone more than doubles net ozone production by aircraft NO emissions and resolves discrepancies between observations and several global model predictions. The actual magnitude of the acetone-attributed enhancement of ozone production can, however, be reduced by PAN formation which acts as a sink for NO x (NO+NO 2) and also lowers the OH/HO 2 ratio.

Sources of upper tropospheric HOX: A three‐dimensional study

The sources of odd hydrogen radicals (HOx = OH + HO2) in the upper troposphere are investigated and quantified using a three‐dimensional model. While the reaction of O(1D) with water vapor constitutes the single major source of HOx in the lower and middle troposphere, the model calculations suggest that acetone photooxidation represents a large, almost ubiquitous source of HOx in the upper troposphere (around 20–40% of the total primary source in the main aircraft corridors, poleward of 40°N), while the convective injections of peroxides and aldehydes are the dominant sources in the tropics, above the oceans and the continents, respectively. The consequences for ozone photochemical production in the upper troposphere are discussed, in particular, in the perspective of the aircraft impact. The role of acetone on ozone photochemical production is estimated and discussed. It is calculated that the presence of acetone might enhance by about 20% the sensitivity of upper tropospheric ozone to the current aircraft emissions of NOx.

Excitotoxicity in CA1 neurons of the rat hippocampus induced by local application of glutamate to a dendritic region

This study investigated the cytotoxic, oxidative and genotoxic effects of two commonly used imidazolium ionic liquids (ILs), [bmim][BF4] (1-butyl-3-methylimidazolium) and [omim][BF4] (1-methyl-3-octylimidazolium tetrafluoroborate), on the marine mussel Mytilus galloprovincialis, as well as whether acetone could mediate their toxic profile. In this context, mussels were firstly exposed to different concentrations of [bmim][BF4] or [omim][BF4], with or without the presence of acetone (at a final concentration of 0.06% v/v), for a period of 96 h, in order to determine the concentration that causes 50% mussel mortality (LC50 values) in each case. Thereafter, mussels were exposed to sub- and non-lethal concentrations of ILs for investigating their ability to cause lysosomal membrane impairment (with the use of neutral red retention assay/NRRT), superoxide anion and lipid peroxidation byproduct (malondialdehyde/MDA) formation, as well as DNA damage and formation of nuclear abnormalities in hemocytes. The results showed that [omim][BF4] was more toxic than [bmim][BF4] in all cases, while the presence of acetone resulted in a slight attenuation of its toxicity. The different toxic behavior of ILs was further revealed by the significantly lower levels of NRRT values observed in [omim][BF4]-treated mussels, compared to those occurring in [bmim][BF4] in all cases. Similarly, [bmim][BF4]-mediated oxidative and genotoxic effects were observed only in the highest concentration tested (10 mg L−1), while [omim][BF4]-mediated effects were enhanced at lower concentrations (0.01–0.05 mg L−1). Overall, the present study showed that [bmim][BF4] and [omim][BF4] could induce not only lethal but also nonlethal effects on mussel M. galloprovincialis. The extent of [bmim][BF4] and/or [omim][BF4]-mediated effects could be ascribed to the length of each IL alkyl chain, as well as to their lipophilicity. Moreover, the role of acetone on the obtained toxic effects of the specific ILs was reported for the first time, giving evidence for its interaction with the ILs and the modulation of their toxicity.

Evidence for Dipolar Interactions in Binary Solvents Containing Acetone

Evidence for Dipolar Interactions in Binary Solvents Containing Acetone

Studies on the mechanisms of induction of N-nitrosodimethylamine demethylase by fasting, acetone, and ethanol

Previous work has shown that induction of a high-affinity NADPH-dependent nitrosodimethylamine demethylase (NDMAd) in liver microsomes occurs in rats due to fasting, ethanol consumption, and streptozotocin-induced diabetes. Several lines of observations suggest that this is due to the induction of specific cytochrome P-450 isozymes. Induction of P-450 species by ethanol has also been observed by other investigators. Since each of the above altered metabolic states has in common elevated levels of ketone bodies, the possible role of acetone, a known inducer of NDMAd, in the induction of the demethylase activity was investigated. Levels of endogenous acetone in fasted rats correlated ( r = 0.72) with a three- to fourfold increase in NDMAd activity. However, a dose-response experiment showed endogenous levels of acetone to be capable of causing at most 40% of the induction in fasted rats. This suggests that other ketone bodies or factors may have contributed to the induction. The induction of NDMAd by ethanol was enhanced by alcohol dehydrogenase inhibitors pyrazole and acetaldehyde oxime, suggesting that ethanol, rather than its metabolites, was responsible for the induction.