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The polyol method was implemented to prepare stable V–ZrSiO4 suspensions as ceramic ink. It was shown how the rheology, surface tension, viscosity, and particle size of suspensions were affected by the length of polyol solvent and dispersants. The effect of ethylene glycols, diethylene glycol (DEG), triethylene glycol, and tetraethylene glycol as solvents, as well as polyvinylpyrrolidone (PVP) and cetyltrimethylammonium bromide as dispersants on the ink properties was investigated. The X-ray diffraction, Fourier-transform infrared (FTIR), electron microscopy (FESEM/TEM) and dynamic light scattering analyses were performed to characterize the features of nanopigments. Crystalline V–ZrSiO4 nanopigment was obtained at 1100°C by DEG solvent in the presence of PVP. The sizes of the resulting nanoparticles were in the range of 10–50 nm. The achieved suspensions were tested as ceramic inks on a tile, and the colorimetric CIELAB parameters were measured. The CIE L*a*b* values confirmed the blue color. The surface tension and viscosity of prepared ceramic ink, as well as microstructure of the annealed nanopigments, were in the range required for drop-on-demand inkjet printers. [ABSTRACT FROM AUTHOR]

An asymmetric spinel-spinel supercapacitor is fabricated with negative and positive electrodes respectively consisting of Fe 3 O 4 and Mn 3 O 4 nanoparticles, where carbon nanotubes (CNT) serve as conductive additives. High performance of the individual electrodes and devices is achieved at a high active mass (AM) loading of 40 mg cm−2 of the individual electrodes. We implement a conceptually new strategy using multifunctional Celestine blue (CB) dye, which is strongly adsorbed on the spinel phases and CNT, facilitates dispersion, acts as a capping agent and allows for the fabrication of spinel decorated CNT. CB is an efficient charge transfer mediator, which allows for significant improvement of capacitive behavior. The use of CB as a charge transfer mediator allows for good utilization of capacitive properties of spinels at high AM. Mechanisms of spinel-CB-CNT interactions and charge transfer mediation are discussed. The capacitive properties of electrodes with different spinel/CNT mass ratios are tested by cyclic voltammetry, chronopotentiometry and impedance spectroscopy. The areal capacitances of 6.17 and 5.15 F cm−2 are obtained for Fe 3 O 4 and Mn 3 O 4 based electrodes, respectively in 0.5 M Na 2 SO 4 electrolyte. The high capacitances are achieved for the electrodes that have low resistance. Using these electrodes, an asymmetric device is fabricated that has a capacitance of 2.41 F cm−2 in a voltage window of 1.6 V. [ABSTRACT FROM AUTHOR]

BiInSn alloy, one of the low-melting-point alloys, has attracted more and more attention in various fields recently. However, research into applying BiInSn powder is limited, and most existing methods of preparing metal powders are not quite suitable for BiInSn alloy due to its special properties. Here, an effective method has been provided to fabricate BiInSn alloy powder based on ultrasonic crushing in combination with the dispersant solution. The effects of the dispersant and the cooling rate on the size distribution and shape of the powder are discussed. The experiment results show that the size of BiInSn powder prepared with ethylene glycol with higher viscosity is much smaller. Compared with bulk metal, the BiInSn powder exhibit more superior properties in the application. For example, the sintered BiInSn powder has better performance in the micro-hardness measurement. The micro-hardness of the products using ethylene glycol increases by 90.7% compared with that of the bulk metal. Besides, the BiInSn powder can be used to fabricate stretchable conductive material. Unlabelled Image • A novel method for fabricating sub-micron BiInSn alloy powder is proposed. • The dispersant viscosity has a remarkable effect on the particle size. • The sintered BiInSn powder has better micro-hardness than bulk metal. • The BiInSn powder can be used to fabricate stretchable conductive material. [ABSTRACT FROM AUTHOR]

Agglomeration is a common problem facing the preparation and application of nanomaterials, and whether nano-hydroxyapatite (nano HA) can modulate oral microecology left to be unclear. In this study, nano HA was disaggregated by sodium hexametaphosphate (SHMP) and ultrasonic cavitation to observe whether agglomeration would affect its effect on oral bacterial biofilm. Dynamic light scattering (DLS) and scanning electronic microscope (SEM) were used to observe the treatment solutions. Single-species biofilms and multi-species biofilms were treated with 10% nano HA, 10% disaggregated nano HA, 10% micro hydroxyapatite (micro HA) and deionized water (DDW) for 30 min and analyzed via MTT assay, lactic acid measurement, SEM and confocal laser scanning microscope (CLSM). Real-time polymerase chain reaction was performed to analyze the biofilm composition. Ultrasonic cavitation combined with SHMP could significantly reduce the degree of agglomeration of nano HA. Disaggregated nano HA could inhibit bacterial growth and reduce the ability of bacterial biofilm to produce lactic acid and extracellular polysaccharides. There was no significant difference on composition of multi-species biofilms between nano HA and disaggregated nano HA. The disaggregated nano-hydroxyapatite could inhibit the metabolism and acid production of oral bacterial biofilm, but did not significantly affect the composition of multi-species biofilms. [ABSTRACT FROM AUTHOR]

Silver (Ag) nanoparticle has extremely high surface energy and it is difficult to find an efficient dispersant to prevent its agglomeration in suspensions. A new brush copolymer, succinic anhydride modified epoxy‐amine poly[(propylene oxide)‐co‐(ethylene oxide)]‐grafted polymer (EPOA), which can efficiently disperse concentrated aqueous suspensions of Ag nanoparticles is revealed. The dispersion efficiency of EPOA for the dispersion of a 60 nm‐Ag nanoparticles in aqueous suspension is studied by measuring its sedimentation and rheological behavior, and the results are compared with those of a commercially available dispersant, ammonium poly(acrylic acid) (PAA‐NH4). Interactions between the dispersants and the Ag nanoparticles are characterized by zeta potential and adsorption analyses. Theoretical calculations are conducted to clarify the adsorption and the dominant dispersion stabilization mechanisms of the dispersants. Compared with PAA‐NH4, EPOA obtains a higher stable suspension of Ag nanoparticles with less significant sedimentation over 1 month. The dispersion homogeneity of the suspension remains excellent even at an extremely high solid loading of 30–40 wt%. According to adsorption analysis, it is suggested that both EPOA and PAA‐NH4 adsorb via single‐point attachment through the carboxyl group on the Ag surface. Based on theoretical calculations, the Ag nanoparticles are better stabilized by EPOA via an electrosteric dispersion mechanism. [ABSTRACT FROM AUTHOR]

Observations made for the analysis of the oil spill dispersant tracer dioctyl sulfosuccinate (DOSS) during LC50 toxicity testing, highlighted a stability issue for this tracer compound in seawater. A liquid chromatography high-resolution quadrupole time-of-flight mass spectrometry (LC/QToF) was used to confirm monooctyl sulfosuccinate (MOSS) as the only significant DOSS breakdown product, and not the related isomer, 4-(2-ethylhexyl) 2-sulfobutanedioate. Combined analysis of DOSS and MOSS was shown to be applicable to monitoring of spill dispersants Corexit® EC9500A, Finasol OSR52, Slickgone NS, and Slickgone EW. The unassisted conversion of DOSS to MOSS occurred in all four oil spill dispersants solubilized in seawater, although differences were noted in the rate of MOSS formation. A marine microcosm study of Corexit EC9500A, the formulation most rapid to form MOSS, provided further evidence of the stoichiometric conversion of DOSS to MOSS under conditions relevant to real world dilbit spill. Results supported combined DOSS and MOSS analysis for the monitoring of spill dispersant in a marine environment, with a significant extension of sample collection time by 10 days or longer in cooler conditions. Implications of the unassisted formation of MOSS and combined DOSS:MOSS analysis are discussed in relation to improving dispersant LC50 toxicity studies. [ABSTRACT FROM AUTHOR]

This article systematically studies the relationship between the dispersity of the mixed suspension, the microstructures and the electrical properties of the ZnO varistors by adjusting the dispersant content and the pH value. The suspension dispersity was measured by viscosity, zeta potential, particle size distribution and TEM observation. The structure of the as-prepared ZnO varistors was characterized by XRD and SEM. The electrical properties were investigated by testing E-J characteristics, breakdown voltage, leakage current, nonlinear coefficient, 8/20 μs waveform current impulse and accelerated aging performance. When the suspension reached the best dispersion condition of 0.3 wt% dispersant and the original pH value, the ZnO varistors had optimum electrical properties: breakdown voltage gradient of 299.95 V mm−1, leakage current I L of 0.33 μA, voltage ratio U 5kA /U 1mA of 1.686, nonlinear coefficient of 46.71, and a downward trend of power consumption in the accelerated aging test. [ABSTRACT FROM AUTHOR]

Calcium silicate hydrate (C-S-H) is the most important hydration product of cement hydration and the most critical source of strength for concrete. In this paper, hydrated calcium silicate early strength agent was synthesized by sol-gel method, and a series of tests were carried out. The results show that the hydrated calcium silicate early strength agent prepared by high-speed stirring and under the action of specific dispersant solution has the smallest particle size and the best dispersion at 25°C. After being blended into cement, it can greatly reduce its nucleation energy barrier, promote cement hydration, significantly shorten the cement setting time and improve early strength of concrete. [ABSTRACT FROM AUTHOR]

The baffled flasks were used to simulate regular wave and breaking wave at different oscillation intensities to study the effects of wave strength, reaction time, and dispersant on the submergence of oil spill. It was found that the wave strength has the greatest impact on submerging rate and submergence stability of Liaohe crude oil and Fuel 180. The characteristics of the impacts of the wave strength and dispersant content are that there are thresholds, below which the impacts are not obvious; their coupling effects are obvious only when both the wave strength and the dispersant content exceed their threshold; the impacts can accumulate over time and have the maximum value; the submerging rate reaches maximum at 30 min for Liaohe crude oil and 60 min for Fuel 180; the submerging rate will decrease after the time of the maximum impact. Based on the experimental results, it is proposed that the submerging model should have different forms based on the thresholds of conditions and different phases of the time, which need more work to be determined for different oils. [ABSTRACT FROM AUTHOR]

Tn this paper, the hydrocarbon PCM slurry with mass fraction of 30% was selected as the base fluid, and a variety of PCM slurry with nano particles (TiO2) and dispersant (SDBS sodium dodecyl benzene sulfonate) were prepared by "two-step methodThe effects of nanoparticle mass fraction, nanoparticle size and dispersant mass fraction on the viscosity of PCM slurry were tested and analyzed. The results show that the larger the mass fraction and the larger the particle size, the higher the viscosity of the phase change fluid at the same temperature. However the viscosity of PCM slurry decreased first and then increased with the increase of mass fraction of dispersant. When the mass fraction of dispersant was 0.J %, the viscosity of PCM slurry reached the minimum. [ABSTRACT FROM AUTHOR]

About 50 fuel formulations based on boron, hydrocarbon binder, and high-enthalpy polynitrogen dispersant were considered. The quantitative dependence of the reachable aircraft range with the optimized fuels on the elemental composition of the dispersant, its enthalpy of formation, and density was examined. The quantitative dependences of the aircraft range on the content of each element constituting the dispersant were obtained, and differences in these quantities were accounted for. Empirical formulas relating the flight range to the above characteristics of the dispersant were obtained; they allow prediction of the ballistic performance of the dispersants (including compounds that have not been synthesized by now) with an error no higher than 1%. [ABSTRACT FROM AUTHOR]

Recent, studies have shown that selective flocculation flotation is an effective method for enhancing the flotation of a fine mineral. Fine-grained collophane is difficult to disperse naturally, thereby affecting its subsequent flotation separation. Therefore, it is important to study the dispersion behaviour and mechanism of fine-grained cellophane to choose an appropriate method to improve the dispersion effect of the flotation system. The influences of different types of poly-anionic dispersants, such as (sodium silicate (ZSS); sodium carbonate (ZSC); sodium hexametaphosphate, ZSP) and metallic cations with different valences (Al3+, Ca2+, Na+) on the dispersion behaviour effect of fine-grained collophane were investigated in this work using the sedimentation balance method. The zeta potential measurements and the extended-DLVO (Derain-Landau-Verwey-Overbake) theory were used to explain the distinction of dispersion behaviour. In the presence of dispersants, the dispersion of collophane was in the order of ZSP>ZSS>ZSC. Zeta potential analysis indicated that the absolute value of the surface potential followed the order of ZSP>ZSS>ZSC. That is, the collophane particles in the ZSP system had stronger electrostatic repulsion, resulting in a better dispersion zeta potential effect zeta potential. ZSP was adopted as dispersant to study the effects of metal ions on dispersion. In the ZSP dispersant system, metal ions can suppress the dispersion behaviour of fine-grained collophane. The suppression effect followed the order of Al3+>Ca2+>Na+, because of the greater charge and better neutralization ability of trivalent ions for the same concentration. The results of the extended-DLVO calculations showed that the dispersion stability was attributed to the electrostatic repulsion and hydration repulsion, and hydration repulsion had a greater influence on the stability than electrostatic repulsion. This paper provides reference information for adjusting the dispersion behaviour effect of fine-grained collophane, thereby guiding the actual flotation separation. [ABSTRACT FROM AUTHOR]

A versatile dispersant plays a critical role in suspension stability of pesticide aqueous suspension concentrate (SC), thus it is extremely important to design and synthesize an effective dispersant for SC. Herein, nonionic trimeric nonylphenol polyoxyethylene (10) (TNP10) was successfully synthesized using nonylphenol polyoxyethylene(10) ethers (NP10) as raw materials. The surface activities of TNP10 were evaluated according to critical micelle concentration (CMC), and the surface tension at CMC (γCMC). TNP10 showed higher surface activity due to its lower CMC value compared with that of NP10. In addition, the dispersing and stabilizing properties of TNP10 in 25 wt.% pyraclostrobin SC system were investigated. The results showed that TNP10 as a dispersant exhibited more excellent dispersion performance than NP10. Meanwhile, the obtained SC system exhibits shear thinning behavior under high-speed shearing showing typical features of pseudo-plastic non-Newtonian fluids, which conforms to the Herschel-Buckley model. The nonionic trimeric nonylphenol polyoxyethylene (10 can effectively improve the surface activities and the suspension rate and stability of SC compared with its monomer NP10. [ABSTRACT FROM AUTHOR]

Phthalocyanine green is a hydrophobic pigment with excellent properties, which is usually dispersed in the organic phase. However, most organic phases are volatile and harmful to the environment and organisms. Therefore, phthalocyanine green dispersed in the aqueous phase has development potential. In this work, cellulose nanocrystals (CNCs) were used as dispersant and stabilizer to disperse phthalocyanine green in the aqueous phase. Phthalocyanine green was added to CNCs colloid to prepare phthalocyanine green suspensions with good dispersibility and stability. The particle size, zeta potential, absorbance and microstructure of the phthalocyanine green suspensions were tested and analyzed. The results showed that CNCs had good dispersibility and stability to phthalocyanine green due to charge repulsion and steric hindrance. The phthalocyanine green suspensions were nano-sized and had well compatibility with different types of coating forming substances. The coatings of the mixture had good water resistance, adhesion and mechanical properties. The suspensions had the application property and could be mixed with coating forming substances to prepare coating materials. As a renewable and easily degraded biomass resource, CNCs are expected to become a new dispersant and stabilizer for pigment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Flotation behavior of lean coal using TCD as a novel dispersant in NaOL system was studied. • With the addition 2000 g/t TCD at pH value of 5, flotation perfect index is greatly increased. • SEM-EDS and turbidimeter analysis reveal that the slime coating is reduced by using TCD. • The attachment energy barrier between low-ash coal and high-ash fine slimes is increased by using TCD. • TCD is an appropriate dispersant for the flotation of lean coal. Flotation is a highly efficient method for purifying low-ash coal particles from high-ash fine slimes. Herein, the dispersion effect of trisodium citrate dihydrate (TCD) on the reduction of slime coating on low-ash lean coal particle surface was studied using flotation tests, scanning electron microscope–energy Dispersive Spectroscopy (SEM–EDS) observation, turbidity measurements, and extended Derjaguin–Landau–Verwey–Overbeek (E-DLVO) calculations. Flotation tests revealed that after adding of 2000 g/t TCD, the yield of clean coal increased by 1.09 % and the ash content of clean coal decreased by 1.45 % with 1000 g/t NaOL at pH 7.0, thereby increasing the combustible recovery and flotation perfect index by 2.50 % and 6.42 %, respectively. The SEM–EDS observation and turbidity measurements indicated that the coating of the high-ash fine slimes on the low-ash coal particle surface was significantly weakened in the presence of 2000 g/t TCD. Furthermore, the E-DLVO calculations verified that the addition of 2000 g/t TCD increased the energy barrier between the low-ash coal particles and high-ash fine slimes, providing theoretical evidence for flotation tests and SEM–EDS observation. Therefore, TCD served as an effective dispersant for the high-ash fine slimes to improve the flotation performance of lean coal. [ABSTRACT FROM AUTHOR]

• BaTiO 3 is conjugated by phosphate ester for small-sized ceramic capacitors. • Solvation of phosphate esters-BaTiO 3 under organic solvents is simulated. • Solvation declines with increasing the hydrophobicity of solvent molecules. • Solvation has a linear correlation with the experimental zeta potential. [Display omitted] Tetragonal BaTiO 3 is a key material for manufacturing multi-layer ceramic capacitors (MLCCs), and a highly dispersed BaTiO 3 suspension, where the surfaces are conjugated by phosphate ester dispersants, is an essential technology for the production of ultra-thin films and small-sized ceramic capacitors. Therefore, understanding the interactions of conjugated polymers with solvents is critical to designing improved dispersants and solvents for commercial MLCC applications. In this work, we theoretically investigate the solvation and inter-chain interactions of mono-alkyl and ethoxy phosphate esters under methanol, ethanol, isopropanol, 1-butanol, and toluene, on tetragonal BaTiO 3 (0 0 1) using the ab initio molecular dynamics (AIMD) simulations. Our results show that the total number of solvent molecules surrounding mono-alkyl and ethoxy phosphate esters decreases in the order of methanol > ethanol > isopropanol > 1-butanol > toluene, indicating that solvation via van der Waals forces and hydrogen bonding declines with increasing the hydrophobicity of solvent molecules. Also, the solvation interaction energy has a linear correlation with the experimental differential of zeta potential, suggesting that the calculated energy is associated with electrostatic environment at the dispersant/solvent/BaTiO 3 interface. Therefore, the solvation interaction energy is an important factor that describes the liquid–solid interfaces as well as a dispersion stability of BaTiO 3 suspension. [ABSTRACT FROM AUTHOR]

Tropical regions like French Guiana need local building materials to cope with high population growth and the high cost of imported cementitious materials. Poured earthen construction could represent a local, cost-effective, and ecologically friendly alternative. To ensure good workability and facilitate pouring, the use of dispersants to deflocculate clay particles is an effective strategy that reduces water demand and increases the material's density and strength. Natural organic dispersants can replace industrial ones while reducing costs and carbon footprint. It is currently unknown how organic dispersants could improve the workability, physical and mechanical properties of the iron-rich lateritic soils present in French Guiana. Here, different potential dispersants were evaluated at constant water content on a lateritic soil-based mortar: citric acid, sodium carbonate, tannins, tannins+sodium hydroxide (tannins+NaOH), tannins+sodium carbonate (tannins+Na 2 CO 3). These dispersants were compared to industrial sodium hexametaphosphate (NaHMP). Three types of tannins were tested: hydrolyzable tannins from oak and chestnut, and condensed tannins from acacia. This study shows that all formulations improved workability and mechanical strength but only tannins+NaOH or Na 2 CO 3 had a strong dispersant effect comparable to NaHMP. Furthermore, tannins+NaOH or Na 2 CO 3 decreased the mortar's density without impacting strength, which may result from reactions between the soil's iron oxides and tannins, as observed by infrared spectroscopy (FTIR). Altogether, these results show that the addition of organic dispersant is an appropriate strategy to improve the fresh and hardened properties of lateritic soils. Particularly, tannins combined with sodium carbonate may represent an eco-friendly dispersant for poured earth in regions with iron-rich lateritic soils. • Eco-friendly dispersants improve lateritic mortar workability. • Tannins with alkali had a strong dispersant effect on lateritic soil. • Infrared spectra showed tannins reacted with soil iron oxide. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of different dispersants on the wettability of pulverized coal was studied. • The wettability ranking of the four dispersants was obtained. • The problem of pulverized coal accumulating and seizure in support cracks is solved. • Guidance for improving gas–liquid permeability and CBM wells extraction effect. This study investigated how to effectively discharge deposited pulverized coal particles in coal-bearing propped fractures and improve the permeability levels of the propped fractures in order to enhance coalbed methane production. Four types of dispersants were selected to carry out wettability and permeability tests, including sodium dodecyl sulfate (SDS), sodium dodecyl benzene sulfonate (SDBS), dodecyl dimethyl betaine (BS-12), and alkyl poly glycoside dodecyl glucoside (APG). The results showed reductions in surface tension of 63.71 to 69.75 %, and reductions in contact angles of 40.08 to 60.46 %, when compared with water injections alone. In addition, under the same closure pressure conditions, the dispersant solutions had increased the permeability of the propped fractures by 76.67 to 123.34 % when compared with that of the water injections, and the pulverized coal discharge rates were increased by 1.44 to 2.41 times. The decreases in closure stress also contributed to the enhancement of the permeability of the propped fractures, with increases of between 11.24 and 29.18 % observed. This study found that for the four tested dispersants, the order of the effective wetting of the pulverized coal particles and enhancement of the permeability of the propped fractures were (from strong to weak) as follows: SDS > BS-12 > APG > SDBS. Among the tested dispersants, the 6 mmol/L SDS dispersant solution was found to be the most effective for improving the wettability of the pulverized coal particle surfaces and achieved the highest permeability improvement of the propped fractures. [ABSTRACT FROM AUTHOR]

In order to reduce the apparent viscosity of lignite coal water slurries (CWSs) and improve its static stability, a series of three-arm amphiphilic block copolymers have been prepared through RAFT polymerization by using poly(ethylene glycol) methyl ether acrylate (PEGMA) and sodium 4-vinylbenzenesulfonate (SSNa) as hydrophilic monomers and styrene (St) as hydrophobic monomer. The chemical structure of the copolymers has been investigated, and the impact of relative molecular weight, hydrophilic/hydrophobic ratio, and ionic group content on the pulping performance of three-arm amphiphilic block copolymers has been examined. The lignite coal water slurries (CWSs) prepared from the block copolymer tri -P(St 50 - s -SSNa 50) 10K - b -PPEGMA 10K exhibit a remarkably low apparent viscosity of 395 mPa·s and excellent static stability when the coal content is at 55 wt% and dispersant content is at 0.5 wt%. Moreover, these CWSs can achieve a maximum pulping concentration of up to 59 wt%. Additionally, the thermogravimetric test reveals insights into the water occurrence in CWSs, indicating that higher levels of free water content correspond to lower apparent viscosities. Suitable hydrophobicity facilitates the removal of internal water from lignite by dispersants, disrupting its flocculation structure and promoting CWSs formation. Meanwhile, the presence of ionic groups enhances the static stability of the resulting CWSs. Furthermore, the adsorption behavior of the three-arm amphiphilic block copolymer dispersant in lignite has been analyzed through XPS testing to elucidate its dispersion mechanism. The use of three-arm amphiphilic block copolymers in preparing lignite CWSs results in lower apparent viscosity and improved static stability, attributed to the amphiphilic and steric hindrance effects of dispersants. This not only expands the application range of lignite CWSs but also highlights the significant potential of this type of dispersant. [Display omitted] • Amphiphilic star block copolymers exhibit excellent performances for CWSs. • The topologic and amphiphilic of copolymers can be adjusted via RAFT polymerization. • The content of free water in CWSs can be improved by appropriate amphiphilic. • Increasing anion segment in copolymers helps to enhance the stability of CWSs. • CWSs with star copolymer possess enhanced performances compared to with linear one. [ABSTRACT FROM AUTHOR]

Background: Dispersants are first order response strategies for oil spill cleanup in an aquatic environment. However, their effects on the biodegradation capacity of indigenous hydrocarbon-degrading microorganisms are little known. Objectives: The influence of a dispersant (DS/TT/066) on the type(s) and growth of hydrocarbon-degrading bacteria (HDB) and hydrocarbon-degrading fungi (HDF) in a crude oil-contaminated medium (water) was investigated in the laboratory for 28 days. Methods: The experiment was set up in duplicates with the first set containing Forcados light crude oil (FLCO) alone in water while the other was a mixture of FLCO and DS/TT/066 (ratio 9:1 v/v). Identification and enumeration of HDB and HDF were conducted according to standard methods. Total petroleum hydrocarbons (TPH) in the test media was analyzed using a gas chromatography/flame ionization detector. Results: The results showed that HDB identified in the FLCO alone included Pseudomonas aeruginosa (day 0), Proteus vulgaris (day 14), P. aeruginosa and Kliebsiella pneumoniae (day 28). However, in the mixture, Escherichia coli was identified on day 14 in addition to the other species observed in FLCO alone. HDF identified in FLCO alone were Candida krusei and Candida albicans (days 0 and 14), Trichosporon cutaneum and C. albicans (day 28). In the mixture, HDF identified were C. albicans (day 0), C. albicans and Aspergillus spp. (days 14 and 28)″ Furthermore, the mixture enhanced the growth of HDBF (average counts: 32.5 × 107 and 225 × 106 cfu/mL) compared to FLCO alone (17.5 × 107 and 17.5 × 106 cfu/mL) by day 14 respectively. Total petroleum hydrocarbon reduction was highest (85%) in the mixture compared to 5% in FLCO alone by day 14. Conclusions: The study demonstrated the biodegradation efficiency of E. coli, P. vulgaris (bacteria), C. albicans and Aspergillus spp. (fungi) in a crude oil-contaminated aquatic environment in conjunction with dispersant use. Further studies in the field are recommended in order to explore their potential for rapid and large scale crude oil clean-up operations. Competing Interests: The authors declare no competing financial interests.

The phase change thermal control method is now widely used in aircraft thermal protection due to its high energy density, constant temperature control, flexible operation, and many other advantages.1–6 However, thermal conductivity of most current phase change materials is low in phase transition process.7–10 This paper will add high thermal nanoparticles to phase change material in order to enhance the thermal conductivity, which, however, has some problems, such as settlement in the macro, reunion at the micro, etc. These problems also influence the improvement of the thermal conductivity. In view of this, a dispersing agent was introduced to these phase change materials, and then the mixed solution was subjected to ultrasonic dispersion. According to the test results, this treatment was effective in maximizing thermal conductivity of the composite phase change materials.

Dispersant application is a primary emergency oil spill response strategy and yet the efficacy and unintended consequences of this approach in marine ecosystems remain controversial. To address these uncertainties, ex situ incubations were conducted to quantify the impact of dispersant on petroleum hydrocarbon (PHC) biodegradation rates and microbial community structure at as close as realistically possible to approximated in situ conditions [2 ppm v/v oil with or without dispersant, at a dispersant to oil ratio (DOR) of 1:15] in surface seawater. Biodegradation rates were not substantially affected by dispersant application at low mixing conditions, while under completely dispersed conditions, biodegradation was substantially enhanced, decreasing the overall half-life of total PHC compounds from 15.4 to 8.8 days. While microbial respiration and growth were not substantially altered by dispersant treatment, RNA analysis revealed that dispersant application resulted in pronounced changes to the composition of metabolically active microbial communities, and the abundance of nitrogen-fixing prokaryotes, as determined by qPCR of nitrogenase (nifH) genes, showed a large increase. While the Gammaproteobacteria were enriched in all treatments, the Betaproteobacteria and different families of Alphaproteobacteria predominated in the oil and dispersant treatment, respectively. Results show that mixing conditions regulate the efficacy of dispersant application in an oil slick, and the quantitative increase in the nitrogen-fixing microbial community indicates a selection pressure for nitrogen fixation in response to a readily biodegradable, nitrogen-poor substrate.

Following the explosion of the Deepwater Horizon MC252 oil rig in 2010, 319 live sea turtles exposed to crude oil and oil-dispersant (Corexit) combinations were admitted to rehabilitation centers for decontamination and treatment. Treatment of oiled sea turtles was guided by expected physiological and pathological effects of crude oil exposure extrapolated from studies in other species and from a single loggerhead sea turtle (Caretta caretta) study. While invaluable starting points, inherent limitations to extrapolation, and small sample size of the experimental exposure study, reduce their utility for clinical guidance and for assessing oil spill impacts. Effects of dispersants were not included in the previous experimental exposure study, and cannot be effectively isolated in the analysis of field data from actual spills. A terminal study of pivotal temperature of sex determination using eggs salvaged from doomed loggerhead nests provided an opportunity for an ancillary exposure study to investigate the acute effects of crude oil, dispersant, and a crude oil/dispersant combination in sea turtle hatchlings. Eggs were incubated at 27.2–30.8°C, and hatchlings were randomly assigned to control, oil, dispersant, and combined oil/dispersant exposures for 1 or 4 days. Contaminant exposures were started after a 3 day post-hatching period simulating nest emergence. Turtles were placed in individual glass bowls containing aged seawater and exposed to oil (Gulf Coast—Mixed Crude Oil Sweet, CAS #8002-05-9, 0.833 mL/L) and/or dispersant (Corexit 9500A, 0.083 mL/L), replicating concentrations encountered during oil spills and subsequent response. Statistically significant differences between treatments and non-exposed controls were detected for PCV, AST, uric acid, glucose, calcium, phosphorus, total protein, albumin, globulin, potassium, and sodium. The principal dyscrasias reflected acute osmolar, electrolyte and hydration challenges that were more numerous and greater in combined oil/dispersant exposures at 4 days. Clinicopathological findings were supported by a failure to gain weight (associated with normal hatchling hydration in seawater) in dispersant and combination exposed hatchlings. These findings can help guide clinical response for sea turtles exposed to crude oil and crude oil/dispersant combinations, and indicate potential impacts on wildlife to consider when deploying dispersants in an oil spill response.

Phytoplankton strongly interact with their associated bacteria, both attached (PA), and free-living (FL), and bacterial community structures can be specific to phytoplankton species. Similarly, responses to environmental stressors can vary by taxon, as exemplified by observed shifts in phytoplankton community structure from diatoms to phytoflagellates after the Deepwater Horizon (DWH) oil spill. Here, we assess the extent to which associated bacteria influence the phytoplankton taxon-specific oil response by exposing xenic and axenic strains of three phytoplankton species to oil and/or dispersant. The dinoflagellates Amphidinium carterae and Peridinium sociale, and the diatom Skeletonema sp., all harbored significantly distinct bacterial communities that reflected their host oil response. Oil degrading bacteria were detected in both PA and FL communities of the oil resistant dinoflagellates, but their FL bacteria were more efficient in lipid hydrolysis, a proxy for oil degradation capability. Inversely, the growth rate and photosynthetic parameters of the diatom Skeletonema sp. was the most impacted by dispersed oil compared to the dinoflagellates, and oil-degrading bacteria were not significantly associated to its microbiome, even in the dispersed oil treatment. Moreover, the FL bacteria of Skeletonema did not show significant oil degradation. Yet, the lack of consistent significant differences in growth or photosynthetic parameters between the xenic and axenic cultures after oil exposure suggest that, physiologically, the associated bacteria do not modify the phytoplankton oil response. Instead, both oil resistance and phycosphere composition appear to be species-specific characteristics that are not causally linked. This study explores one aspect of what is undoubtedly a complex suite of interactions between phytoplankton and their associated bacteria; future analyses would benefit from studies of genes and metabolites that mediate algal-bacterial exchanges.

This study assessed the physicochemical characteristics and toxicity of water-accommodated fraction (WAF) and chemically enhanced WAF (CEWAF) of Bonny Light Crude oil and Dispersit SPC 1000 (dispersant) to Mudskipper fish (Periophthalmus Papilio). There were variations in the levels of the physicochemical parameters. The coefficient of variation (CV) indicated that the temperature show the least variation of 2.24% and salinity the highest 98.12%.Hypothesis test for significant differences at p < 0.05 significance level however, showed that there were no significant differences in the levels of the measured parameters over the 96 hours. All the mudskippers fish samples exposed to the water accumulated water fraction of 10% bonny oil survived beyond 96 hours. An increase in toxicity of the oil was observed after 72-96 hour exposures of the mudskipper to the oil and dispersant CEWAF. For dispersant concentrations of 540 ml/L and 630 ml/L the survival of mudskippers was 80%. These mortalities might be due to the toxic effect of the dispersant, Dispersit SPC 1000.The Total Petroleum Hydrocarbon (TPH) and the Polycyclic Aromatic Hydrocarbon (PAH) in the test media were respectively 7.66-63.18 ppm and 0.82-5.26 ppm.10% Bonny light crude oil WAF had no effects on mudskipper survival. Exposures to 540 ml/L and 630 ml/L Dispersit SPC 1000 dispersed oil WAF (CEWAF) resulted in 20 % mortality. The lethal dose concentration was 885.5 ml/L (88.55%). The lowest observed effect concentration (LOEC) was found to be 540 ml/L. Keywords: Water-accommodated fraction, chemically enhanced fraction, Dispersant, Mudskipper fish

A lignin modified salt-resistant branched high-performance water reducer was prepared via free radical polymerization. The water-reducing agent was identified through its NMR spectrum, elemental analysis, Fourier transform infrared analysis, thermal gravimetric analysis, and scanning electron microscopy. The experiment conducted on cement paste demonstrates that the water-reducing efficiency can reach a maximum of 44%. Additionally, the significant spatial steric hindrance of the application enhances the dispersal capability of the water-reducing agent, resulting in effective water reduction and reduced viscosity. In addition, its compressive strength is the highest after 3-day curing and 3-, 7-, 28-day standard curing, and it has the best overall performance both in water and saline water prepared systems. The application in oil cement slurry shows that it exhibits a good dispersibility in fresh water, saline water, and substitute ocean water. In the Halfaya and Missan Oilfields of Iraq, BHPWR was used in a slurry with a density of 2.28 g/cm 3 for casing the salt paste layer of five wells. The cementing results exceeded expectations with 100% qualified including over 85% excellent.

Cathodes for supercapacitors with enhanced capacitive performance are prepared using MnO2 as a charge storage material and carbon nanotubes (CNT) as conductive additives. The enhanced capacitive properties are linked to the beneficial effects of catecholate molecules, such as chlorogenic acid and 3,4,5-trihydroxybenzamide, which are used as co-dispersants for MnO2 and CNT. The dispersant interactions with MnO2 and CNT are discussed in relation to the chemical structures of the dispersant molecules and their biomimetic adsorption mechanisms. The dispersant adsorption is a key factor for efficient co-dispersion in ethanol, which facilitated enhanced mixing of the nanostructured components and allowed for improved utilization of charge storage properties of the electrode materials with high active mass of 40 mg cm−2. Structural peculiarities of the dispersant molecules are discussed, which facilitate dispersion and charging. Capacitive properties are analyzed using cyclic voltammetry, chronopotentiometry and impedance spectroscopy. A capacitance of 6.5 F cm−2 is achieved at a low electrical resistance. The advanced capacitive properties of the electrodes are linked to the microstructures of the electrodes prepared in the presence of the dispersants.

Dispersants including Tween 20, Tween 40, Tween 60, and polyacrylic acid (PAA) were used to modify nanoscale zero-valent iron (nZVI). All dispersants dispersed nZVI effectively. PAA-modified nZVI was more stable than nZVI that was modified with Tween surfactant. Iron nanoparticles that were prepared using 0.5–5.0% (vol%) of PAA remained in suspension for more than 2 h. nZVI that was modified using Tween surfactant remained in suspension for 30–60 min, and there was complete sedimentation of bare iron in 10 min. When 2.0–5.0% (vol%) of Tween surfactant was used, the stability of the nZVI that was modified using Tween 20 was much better than that for nZVI that was modified using Tween 40 or Tween 60. The results for the transportation test show that nZVI that was prepared using 2% (vol%) of Tween 20 exhibited the best mobility in porous media. Approximately 83–90% of TCE was degraded by bare, PAA-modified, and Tween 20-modified nZVI, and about 63–67% of TCE was removed by nZVI that was modified using Tween 40 and Tween 60 during 20 days of reaction. The production of cis-dichloroethene (DCE) and 1,1-DCE demonstrates that TCE is removed via reductive dechlorination. The results of this study show that PAA- and Tween 20-modified nZVI are more practical for in situ remediation because they exhibit good mobility and degrade TCE effectively. [ABSTRACT FROM AUTHOR]

In ceramic wet-shaping processes, the effects of the addition of binder is seldom taken into account when determining the optimum amount of dispersant to be used. Hence, in this study, the effect of the addition of PVA, which is commonly used as a binder, on the particle dispersion state of aqueous BaTiO 3 slurry was investigated. Dispersant adsorption, rheological characteristics evaluation, and sedimentation tests were conducted on slurries with and without PVA addition. The slurry with 2 mg･g−1 PCA but no PVA was well dispersed; however, the addition of PVA caused significant aggregation. Although slurries containing more than 4 mg･g−1 PCA plus PVA were more aggregated than those without PVA, the amount of aggregation was less than that with 2 mg･g−1 PCA. The aggregation mechanism was the interaction between PCA as a dispersant and PVA, with the degree of aggregation depending on the amount of non-adsorbed PCA. [ABSTRACT FROM AUTHOR]

Dispersant application is a primary emergency oil spill response strategy and yet the efficacy and unintended consequences of this approach in marine ecosystems remain controversial. To address these uncertainties, ex situ incubations were conducted to quantify the impact of dispersant on petroleum hydrocarbon (PHC) biodegradation rates and microbial community structure at as close as realistically possible to approximated in situ conditions [2 ppm v/v oil with or without dispersant, at a dispersant to oil ratio (DOR) of 1:15] in surface seawater. Biodegradation rates were not substantially affected by dispersant application at low mixing conditions, while under completely dispersed conditions, biodegradation was substantially enhanced, decreasing the overall half-life of total PHC compounds from 15.4 to 8.8 days. While microbial respiration and growth were not substantially altered by dispersant treatment, RNA analysis revealed that dispersant application resulted in pronounced changes to the composition of metabolically active microbial communities, and the abundance of nitrogen-fixing prokaryotes, as determined by qPCR of nitrogenase (nifH) genes, showed a large increase. While the Gammaproteobacteria were enriched in all treatments, the Betaproteobacteria and different families of Alphaproteobacteria predominated in the oil and dispersant treatment, respectively. Results show that mixing conditions regulate the efficacy of dispersant application in an oil slick, and the quantitative increase in the nitrogen-fixing microbial community indicates a selection pressure for nitrogen fixation in response to a readily biodegradable, nitrogen-poor substrate. [ABSTRACT FROM AUTHOR]

Asphaltene deposition can cause serious problems during petroleum refinery. In this paper, oil-soluble MAC series asphaltene dispersants with comblike structure were synthesized by free- radical polymerization and amination. The asphaltene deposition inhibition was investigated by determining the flocculation onset of blended crude oil (Tahe: Northern Xinjiang = 20:80 (w/w)) and conducting dynamic thermal deposition experiment. The results showed that MAC3 had the best performance and the flocculation onset of crude oil increased from −20.5 to 3.89 when the dosage of MAC3 was 150 mg/L. The anti-scaling rate of MAC3 was 60% in dynamic thermal deposition experiment of blended crude oil. [ABSTRACT FROM AUTHOR]

Dispersants are used to reduce the impact of oil spills in marine environment. Experiments were conducted with natural materials which were contaminated by direct application of fresh Louisiana crude oil. The natural materials evaluated included sea sand (South Beach in Miami, Florida), red mangrove leaves (Rhizophora mangle), and sea shells (Donax variabili). Salt water at two different salinities (17 and 34 ppt) was used with two types of Corexit dispersant solutions (9500A and 9527A) in concentrations ranging from 100 to 3500 mg/L. Washing of the contaminated samples was conducted by a three-step mixing procedure (salt water only, then with the addition of the dispersant solution to the salt water, and salt water) to simulate oil-saltwater-dispersant interactions. In general, increasing dispersant concentration increased the percentage of oil dispersed into the aqueous phase up to dispersant solutions containing 400 mg/L for Corexit 9500A and 300 mg/L Corexit 9527A. Increasing the dispersant concentration above these levels also decreased the dispersion of oil from the surfaces. At very high concentrations of dispersant solutions (above 1500 mg/L), the percentage of oil dispersed into the solution from the contaminated surfaces was about one half what was observed at 400 mg/L with Corexit 9500A and 300 mg/L Corexit 9527A. Although dispersants were most effective for removing the fresh Louisiana crude oil from sand particles and dispersing into the solution due to large surface area of the particles per unit weight; the residual oil remaining on the sand particles was relatively high in comparison to mangrove leaves and sea shells due to clustering of sand particle with oil. There was some oil penetration into the porous structure of the sea shells (at the microscopic level) which could not be removed. Image 1 • A three step washing process was used to clean crude oil contaminated natural materials. • Two commonly used oil spill dispersants (Corexit 9500A and Corexit 9527A) were evaluated. • Contaminated sea sand, shells (Donax variabili), and r ed mangrove (Rhizophora mangle) leaves were evaluated. • Increasing dispersant concentration up to 400 mg/L increased the oil dispersed into the aqueous phase. • Higher residual oil remained on sand surfaces due to clustering of particles with oil. [ABSTRACT FROM AUTHOR]

Abstract：Fracture in silicon anodes is a commonly fundamental problem, which results in ca. 80% capacity loss over the electrochemical cycles. Alginate, as one of many water-soluble polysaccharides, are efficient binder systems for silicon (Si) electrode due to their strong interface bonding with Si surface. However, the rigidness and brittleness of the polysaccharides induce dense fracture on the Si anode. In this work, a facile and effective physical approach is proposed by introducing glycerol as the plasticizer in the electrode processing. Glycerol contributes to an improvement of the ductility and flexibility of the binder, which effectively alleviates the fracture formation and propagation during repeated electrochemical cycles. At the optimum alginate/glycerol weight ratio of 2:1, silicon anode displays much improved electrochemical performances in terms of the long-term cycling performance and the rate capability. The well-preserved physical integrity of the Si anode after long-term cycles explains the electrochemical enhancement. The facile and effective dispersant optimization in electrode processing provides a new avenue for Si electrode fabrication with high electrochemical performances. The well known dry-bed fracture for silicon anode after electrochemical cycles is successfully suppressed by improving the mechanical properties of the alginate binder with glycerol plasticizer in the electrode processing. As the result, cycling stability of the silicon anodes is significantly improved. Image 1 • Dispersant modification is done by introducing glycerol in electrode processing. • Low Young's modulus and large elongation for the alginate binder is obtained. • The plasticized Si anode exhibits high rate capability and prolonged life-span. • The reduced fracture on the Si laminate explains the electrochemical enhancement. [ABSTRACT FROM AUTHOR]

The energy of combustion ΔH°c of 4H,8H-bis(furazano)[3,4-b:3′,4′-e]pyrazine (BFP) was measured by calorimetry in the oxygen atmosphere and the standard enthalpy of formation ΔH°f was calculated. The real ΔH°f value was found to be 33 kJ mol−1 higher than reported before. The obtained results were used for correction of the evaluated efficiency of using BFP as a solid fuel dispersant for rocket ramjet engines, which showed high BFP performance. [ABSTRACT FROM AUTHOR]

The paper reports the synthesis of a new compound named diglyceryl acrylate (DGA) and its application in manufacturing of ZTA composites by gelcasting method. The compound can be used as a monomer able to polymerize in suspensions and also as a dispersing agent for fine-crystalline powders. The paper describes the synthesis of DGA, the properties of the monomer, the resulting polymer, ceramic suspensions and sintered bodies. The distribution of zirconia grains in alumina matrix was observed on SEM. Vickers hardness and fracture toughness of ZTA composites have been measured. The research revealed that with the use of DGA it is possible to obtain highly concentrated ceramic suspension (60 vol%) of low viscosity. The positive influence of the new monomer on the properties of ceramic suspensions and sintered bodies is explained on the basis of the analysis of spatial structures of all 8 regioisomers of DGA molecule. [ABSTRACT FROM AUTHOR]