Addition Of Nonionic Surfactant Research Articles

A post-emergence herbicide program for weedy sunflower (Helianthus annuus L.) control in maize

During the last 15 years in Serbia, there has been an invasion of H. annuus across the country. Plants were initially limited to non-cultivated areas near arable fields, while in recent years the species has started to occur and establish populations in crop fields, especially into wide-row crops. We tested eight herbicides in two greenhouse experiments: 1) a dose-response study; 2) an efficacy study with reduced herbicide rates adding an adjuvant. The tested herbicides showed satisfactory weed control, where all estimated effective doses 90 (ED90) were lower than the recommended field rate for each herbicide, except for dicamba. The addition of non-ionic surfactants significantly increased the efficacy of glyphosate, mesotrione, rimsulfuron, and foramsulfuron. Whereas, there was no clear advantage to adding an adjuvant to bentazone and tembotrione, as the H. annuus population was already very sensitive (plants died in 1/8 of recommended rate in a dose-response study). All tested herbicides, except dicamba, can be used for satisfactory H. annuus control in maize, while glyphosate can be used for control of the species in non-agricultural lands.

Boosting concurrent yeast oil production and secretion by Rhodosporidium toruloides through non-ionic surfactant addition and gene expression monitoring

Yeast oil (YO) secretion derived from glycerol was facilitated by non-ionic surfactant-enhanced conditions, leading to extracellular yeast oil formation and expression of the ACC and DGA genes. The kinetic parameters of oleaginous yeast cultivation were estimated by employing through mathematical modeling. Seven yeast strains were cultivated on a glycerol-based oil production medium. Rhodosporidium toruloides TISTR 5186 demonstrated the highest efficacy in YO production and was chosen to investigate the impact of non-ionic surfactant supplementation on releasing intracellular YO into the extracellular space. Adding Triton X-100, Tween 20, and Brij 58 induced the release of YO by R. toruloides. Highest total YO formation and oil content were observed at 4.00 ± 0.07 g/L and 78.38 ± 0.37% (w/w) for 0.7% (w/v) Tween 20, respectively. Under this condition, the expression of the ACC and DGA genes was significantly increased by 3.4 and 3.6-fold, respectively compared to the control treatment. The YO fatty acids were consistently dominated by C16:0 and C18:1 under different yeast strains and cultural conditions. Modulation of YO secretion by non-ionic surfactants is a simple technique for enhancing oil recovery without the need for cell digestion. This strategy is a promising and straightforward process that can be employed for simultaneous oil production and recovery.

Morphology and Stoichiometry Dependent Electrocatalytic Activity of Cu2ZnSnS4 for Hydrogen Evolution Reaction (HER) with Addition of Nonionic Surfactants

Morphology and Stoichiometry Dependent Electrocatalytic Activity of Cu2ZnSnS4 for Hydrogen Evolution Reaction (HER) with Addition of Nonionic Surfactants

Enhancing ceria slurry performance for shallow trench isolation chemical mechanical polishing through non-ionic surfactant addition

Enhancing ceria slurry performance for shallow trench isolation chemical mechanical polishing through non-ionic surfactant addition

Diffusion kinetics of molecular probe in thin poly(vinyl alcohol)-based films

We investigated the diffusion characteristics of a molecular probe in organic films of poly(vinyl alcohol) (PVA) that replicate formulations used as packaging materials. Diffusion kinetics of Rhodamine B (RhB) was measured in thin films of PVA containing glycerol and surfactants of various headgroup chemistry (cationic/nonionic/anionic) using fluorescence recovery after photobleaching and atomic force microscopy. Here we show how diffusion is determined by both molecular arrangement within the film and the nature/magnitude of intermolecular interactions. Addition of glycerol could improve the flexibility of PVA chains initially but imposed steric inhibition once the concentration exceeded the threshold of 44 wt%. In all investigated formulations, RhB exhibited diffusion-coupled mechanism. The presence of surfactants (at 6 wt%) reduced the diffusivity of RhB in PVA matrix for all types of surfactants used (by 30 %, 61 %, and 88 % for cationic, nonionic, and anionic surfactant addition compared to control sample, respectively). We conclude that steric inhibition effects underpin the diffusion of RhB in PVA thin films doped with nonionic surfactant. However, for PVA films with the addition of cationic or anionic surfactant, interactions between surfactant and fluorophore are likely responsible for the change in diffusivity of the molecular probe.

Influence of various colloidal surfactants on the stability of MS2 bacteriophage suspension. The charge distribution on the PCV2 virus surface

To understand virus stability in aqueous solutions, the colloidal nanostructure and properties of a model virus, the MS2 bacteriophage, have been investigated by studying the effect of the addition of electrolytes and various colloidal surfactants to its water solution at physiological conditions. The charge of the virus particles influences their colloidal properties. It was found that the ζ-potential value is reduced from –35 mV to –10 mV in 0.01 M CaCl2 and 0.1 M NaCl solutions as well as at higher electrolytes concentrations, while the size of the MS2 aggregates was about 600 ÷ 900 nm with individual particles of size around 30 nm also recorded. The 2 :1 electrolyte causes destabilization of MS2 bacteriophage particles in an aqueous solution at a lower concentration. The addition of cationic, anionic, and non-ionic colloidal surfactants below and above critical micelle concentration to MS2 bacteriophage suspension caused the destabilization of MS2 particles. We also investigated the capsid’s surface of another virus, PCV2, using dynamic light scattering and laser Doppler electrophoresis. The hydrodynamic diameter and the ζ-potential of PCV2 empty capsid were found to be equal to 22 ± 1 nm and −41 ± 4 mV (using Ohshima approximations). The electrostatic potential of the surface was measured using acid-base probes and found to be equal to −91 ± 3 and +14 ± 2 mV for positively and negatively charged probes respectively, which indicate the ‘mosaic’ way of the charge distribution on the surface, similar to MS2′s surface studied previously. Our data provide new information about the virus surface, the complex process of virus aggregation-disaggregation and virus capsid disassembly.

Effect of nonionic surfactants on the synergistic interaction between asphaltene and resin: Emulsion phase inversion and stability

Interaction between surface active components in crude oils and nonionic surfactants plays an important role in phase inversion behavior of crude oil emulsion, while the interaction mechanism is not yet fully explored. Herein, the effects of nonionic surfactants on the synergistic interaction between asphaltene and resin, emulsion stability, and emulsion phase inversion were investigated. It is shown that the addition of Span 80 and Tween 80 promotes the reduction of phase inversion point of water in oil emulsion stabilized by asphaltene and resin, as well as increases the yield strain value of the emulsion. The addition of Tween 80 to the asphaltene and resin mixture reduces the inversion point from 70 % to 30 %. The decrease of phase inversion point is attributed to the difficulty in the formation of multiple emulsions after adding nonionic surfactants. The addition of nonionic surfactants can affect the hydrogen bonding between asphaltene and resin, thereby improving the emulsion stability. Span 80 coexists with asphaltene and resin at oil-water interface, reducing the Turbiscan Stability Index (TSI) of emulsion by 15 and improving the strength of the oil-water interface membrane. In comparison, Tween 80 with stronger hydrophilic ability dissolves asphaltene and resin into bulk phase, which leads to the oil-water interface occupied by a large amount of Tween 80. Its numerous EO groups result in the strong hydrogen bonding on the oil-water interface membrane, effectively increasing the strength of the oil-water interface membrane and reducing the TSI by 19. This work contributes to a better understanding of the phase inversion of crude oil emulsion and improves crude oil recovery.

Promotion of droplet deposition, diffusion-wetting and retention on hydrophobic surfaces by nonionic star-shaped oligomeric surfactants

Massive wastage of pesticides has caused significant environmental pollution and economic loss. However, existing strategies to control loss of pesticides are complex or step-specific. Here, nonionic star-shaped surfactants that can simultaneously achieve comprehensive regulation of deposition, diffusion-wetting and retention are designed and synthesized, which greatly improve the utilization efficiency of pesticides while reducing environmental risks. Structure–activity relationships for the surfactants were elucidated, and their interactions with hydrophobic surfaces were studied in detail. The results show that the addition of nonionic star-shaped oligomeric surfactant to a solution decreased droplet bouncing, increased the diffusion-wetting area, slowed droplet evaporation; and the surfactant III-8b showed the best performance. On the basis of these results, III-8b was used as a synergist for Glyphosate-isopropylammonium 41 % AS. The biological activity test showed that the herbicidal activities of the surfactant III-8b-containing glyphosate solution against Pharbitis nil (L.) Choisy and Echinochloa crusgalli (L.) were substantially better than the activities in the absence of surfactant.

Biosurfactant Based Reverse Micellar Extraction of Lactoperoxidase from Whey: Exploitation of Rhamnolipid Characteristics for Back Extraction

ABSTRACT Biosurfactant-based reverse micellar extraction of Lactoperoxidase (LP) was studied using Rhamnolipid (RL) as a biosurfactant. Different solvents were considered to select a suitable organic phase for forming reverse micelles (RM) to varying concentrations of RL for the extraction of LP from its synthetic aqueous solution. The effect of addition of nonionic surfactant as lipophilic linker, whey pH, and ionic strength of the whey was studied to improve the forward extraction of LP from acid whey. About 96.65% LP was extracted to the RM phase during forward extraction. Further, a new back extraction strategy was developed by harnessing the biosurfactant properties. The pH-specific protonation–deprotonation characteristic of the RL headgroups was exploited to overcome the back extraction of LP, which is the rate-limiting step. The back extraction in citrate buffer at pH 5 using 0.75 M KCl resulted in 85.71% active LP recovery with 8.4-fold purification. The effect of the extraction process on the antimicrobial activity of LP was further examined with S. aureus, and the multiplication of the organism was almost arrested even after 24 hr at 9°C.

Study of Cationic Surfactants Raw Materials for COVID-19 Disinfecting Formulations by Potentiometric Surfactant Sensor.

The behavior of a new 1,3-dioctadecyl-1H-imidazol-3-ium tetraphenylborate (DODI-TPB) surfactant sensor was studied in single and complex mixtures of technical grade QACs-benzalkonium chloride (BAC), N,N-didecyl-N,N-dimethylammonium chloride (DDAC), and N,N-dioctyl-N,N-dimethylammonium chloride (DOAC) usually used in COVID-19 disinfecting agents formulations. The results obtained with the new DODI-TPB sensor were in good agreement with data measured by a 1,3-dihexadecyl-1H-benzo[d]imidazol-3-ium-tetraphenylborate (DMI-TPB) surfactant sensor, as well as two-phase titration used as a reference method. The quantitative titrations of a two-component mixture of the cationic homologs (a) DDAC and DOAC; and (b) BAC and DOAC showed that the new DODI-TPB surfactant sensor can clearly distinguish two separate mixture components in a single potentiometric titration curve with two characteristic inflexion points. The consumption of SDS (used as a titrant) in the end-point 1 (EP 1) corresponded to the content of DDAC (or BAC), whereas the consumption in the end-point 2 (EP 2) corresponded to the total content of both cationic surfactants in the mixture. DOAC content in both mixtures can be calculated from the difference of the titrant used to achieve EP1 and EP2. The addition of nonionic surfactants resulted in the signal change decrease from 333.2 mV (1:0; no nonionic surfactant added) to 243.0 mV (1:10, w/w). The sensor was successfully tested in ten two-component COVID-19 disinfecting formulations.

Rhodamine 6G-Anionic Surfactant System Modified by Triton X-100 for Fluorescence Determination of Albumin.

The influence of sodium hexadecyl sulfate on the nature of the fluorescence spectra of rhodamine 6G in an aqueous solution and a solution of nonionic Triton X-100 was investigated. The change in the nature of the emission spectra is explained by the formation of hydrophobic stoichiometric and sub-stoichiometric reagent-surfactant associates. Stabilization of the colloid-chemical state and reduction of the total turbidity of rhodamine 6G-anionic surfactant associate solutions with the addition of nonionic surfactant as a modifier were registered. The method of modification of the rhodamine 6G-sodium hexadecyl sulfate system with a nonionic surfactant was used in the development of conditions for the fluorescence determination of protein substances in physiological solutions. The concentration conditions for the use of the modified reagent system rhodamine 6G-anionic surfactant-nonionic surfactant for the fluorescence determination of albumin in urine were optimized.

Interaction and micellar behavior of ternary mixture of amphoteric amino sulfonate surfactant with traditional anionic and nonionic surfactants: Effect of hydrophilicity

The micellization and the molecular interaction behaviors for two ternary mixtures constituted by an amphoteric sodium 3-(n-dodecyl ethylenediamino)-2-hydroxypropyl sulfonate (C12AS), an anionic sodium dodecylbenzene sulfonate (SDBS) and a nonionic octylphenol polyoxyethylated ether with the number (n) of oxyethylene glycol ethers OP-n (n = 10 or 7) in aqueous solution were investigated using the tensiometry and the effect of hydrophilicity on them was also discussed. In the framework of pseudophase separation model and based on the regular solution theory, the related micellization parameters including the mixed critical micelle concentration (cmc) values in the ideal and real cases, the activity coefficients and the compositions in mixed micelle, etc. and thermodynamic parameters were estimated by the Clint’s model and the Rubingh’ model. The mixed cmc value is dependent on the composition in aqueous solution and influenced by the hydrophilicity of nonionic surfactant. With increasing the nonionic in ternary mixture, the mixed cmc value is initially decreased and then slightly rise. An increasing in the hydrophilicity of nonionic will make the minimum value of mixed cmc be increased from 1.299 mM to 1.705 mM. The resulting phenomena can be explained reasonably by the electrostatic effect, the steric hindrance, the hydrogen bonding, etc. Thermodynamic data indicate that the contribution of entropy or enthalpy plays a vital role on the spontaneous process of micellization and the share of entropy or enthalpy in free energy change is dependent largely on the amount of nonionic surfactant and the hydrophilicity. In ternary mixtures of C12AS/SDBS/OP-10, an increase in an amount of OP-10 will induce the change from the enthalpy-driven micellization process to the entropically favorable process. Once an abundant amount of OP-7 is added, while, the enthalpy will make a main contribution on the micellization process, which can be described by the drop in the share of entropy at the composition (0.6970/0.0000/0.3030) of ternary mixture from 0.6478 to 0.4901. These findings will help with understanding the molecular interaction behavior for the ternary surfactant mixture and the effect of the addition of nonionic surfactant and its hydrophilicity.

Surfactant induced catastrophic collapse of carbon black suspensions used in flow battery application

HypothesisCarbon black particles act as electronically conductive additives in the slurry electrodes used in electrochemical redox flow batteries. Modifying the carbon black slurry formulation with the addition of a nonionic surfactant could impart improved particle dispersion, gravitational stability, and flowability leading to better battery performance. ExperimentsCarbon black particles were dispersed in 1 M H2SO4 with volume fractions Φ = 0.01 to 0.06 and a nonionic surfactant (Triton X-100) concentration of csurf. = 0, 0.05, and 0.1 M. Particle size was characterized using microscopy and surfactant adsorption using UV–vis spectroscopy. Sedimentation kinetics was measured using a custom camera set-up that tracks the height of the settling particle bed. Rheology experiments were conducted to measure linear viscoelasticity and shear flow behavior. FindingsThe sedimentation dynamics of the slurry resembled that of a gel collapse. At short times we observed fast sedimentation associated with structural gel collapse and at long times very slow sedimentation associated with compaction of the sediment. Rheological investigations revealed that the slurry indeed behaved like colloidal gels. Addition of nonionic surfactant at α (= (csurf./cCB)) < 0.75 improved particle dispersion and increased gel elasticity. However, α> 0.75 led to a weaker gel that exhibits a fast ‘catastrophic collapse’ under gravity.

Mixed micellar solubilization for procion blue MxR entrapment and optimization of necessary parameters for micellar enhanced ultrafiltration

In this study, micellar enhanced ultrafiltration, MEUF, being an active methodology, has been employed to remove Procion Blue MxR (PBM) from synthetic effluent. MEUF is being applied to reduce the toxicity level of aqueous system using the micellar media of cationic surfactants i.e. Cetyl trimethylammonium bromide (CTAB) and cetylpyridinium chloride (CPC). Subsequently, the effect of addition of nonionic surfactant, Triton X-100 (TX-100), on solubilizing power of cationic surfactants is investigated. The values of partition coefficient and free energy of partition reflect the extent of interaction of the dye with the surfactants. Initially molecules of pollutants i.e. dye form ion pairs with ionic surfactants and, later on, the same is incorporated within micelle. Maximum value of free energy of partition ΔGp has been found to be −55.49 kJmol-1 and -50.43 kJmol in the presence of CPC and CTAB, respectively. The size of pollutant, thus, increases and, consequently, can be easily filtered. The effect of various factors i.e. concentration of surfactant, concentration of electrolyte (NaCl), transmembrane pressure, revolutions per minute (RPM) and pH, have been investigated to find the optimum conditions for maximum removal of PBM from aqueous system. The efficiency of MEUF has been assessed by calculating the values of rejection percentage and permeate flux. Both the surfactants were observed as strong candidates for PBM encapsulation but overall, maximum rejection percentage (R%) of 96.90% was attained by CPC.

Constraining the Effect of Surfactants on the Hygroscopic Growth of Model Sea Spray Aerosol Particles

The cloud condensation nuclei activation of sea spray aerosol (SSA) is tightly linked to the hygroscopic properties of these particles and is defined by their physical and chemical properties. While hygroscopic sea salt in SSA strongly influences particle water uptake, the marine-derived components that make up the organic fraction of SSA constitute a complex mixture, and their effect on hygroscopic growth is unknown. To constrain the effect of organic compounds and specifically surface-active compounds that adsorb on particle interfaces, particle hygroscopic growth studies were performed on laboratory-generated model sea salt/sugar particles. For sea salt/glucose particles, ionic surfactants facilitated water uptake at low relative humidity (RH), increasing the particle growth factor (GF) by up to 7.61%, and caused a reduction in the deliquescence relative humidity (DRH), while nonionic surfactants had a minimal effect. Replacing glucose with polysaccharide laminarin in sea salt/sugar/surfactant particles caused a reduction in GF at low RHs and minimized the effect of ionic surfactants on the DRH. At RHs above the DRH, the addition of anionic or nonionic surfactants caused a decrease in GF for both sea salt/glucose and sea salt/laminarin particles. The addition of cationic surfactants, however, did not have a dampening effect on water uptake of sea salt/sugar particles and even showed a GF increase of up to 3.7% at 90% RH. An increase in the complexity of the sugar dampens the water uptake for particles containing nonionic surfactants but increases the water uptake for cationic surfactants. The cloud activation potential for 100 nm particles analyzed in this study is higher for ionic surfactants and decreases with an increase in surfactant molecular size when particle interfacial tension is considered. The surfactant effect on the hygroscopic growth and cloud activation potential of the particles containing sea salt/sugar is dependent on the surfactant ionicity and molecular size, the particle size and interfacial tension, and the interactions between inorganic salt and organic species under different RH conditions.

"EFFECTS OF SURFACTANT APPLICATION ON ACACIA HYBRID KRAFT PULP PROPERTIES"

"Acacia hybrid kraft pulping, with the addition of different non-ionic commercial surfactants, as well as its subsequent elemental chlorine free (ECF) bleaching, was studied. The characteristics of bleachable pulps made by conventional kraft and by kraft-surfactant pulping methods were investigated. The results revealed that the type and dosage of the surfactants during the production of Acacia hybrid kraft pulp had no significant influence on the kappa number, screen yield, and reject. On the other hand, the extractive content and brightness of Acacia hybrid bleached kraft pulp were considerably affected by the types and dosages of surfactants used. The addition of 0.1% LAE (linear alcohol ethoxylate) on oven-dried chips lowered the extractive content by 58.20%, whereas 0.125% PEG (polyethylene glycol esters of fatty acids mixed with block copolymer of ethylene oxide with propylene oxide) on oven-dried chips reduced the brightness by 2.78%. Furthermore, the addition of surfactants had no discernible effect on the specks of dirt."

Lipase Catalysis in Mixed Micelles

AbstractThe catalytic performance of lipase, an interfacially active enzyme, depends on the reaction medium. Novel reaction media like mixed micelles affect lipase catalysis mostly by stabilizing the lipase structure and increasing the substrate solubilization. Nonionic surfactant addition in ionic micelles formed mixed micelles and increased lipase catalysis by lowering detrimental lipase‐ionic surfactant hydrophobic and electrostatic interactions. Nonionic/nonionic mixed micelles enhanced activity and enantiomeric selectivity of free lipase but reduced those for immobilized lipase. Nonconventional cationic/cationic, anionic/nonionic/ionic liquid, and substrate/nonionic mixed micelles also improved lipase catalysis. Lipase activity was high in bile salt/surfactant mixed micelles but was low in bile salt/phospholipid mixed micelle. Mixed micelles have advantages like improving lipase‐substrate interaction, increasing water nucleophilicity, sometimes greater emulsion stability, and reduced product inhibition. In mixed micelles, increasing the lipase concentration can overcome the problem regarding inaccessibility of insoluble substrates.

Elucidating the Impact of Surfactants on the Performance of Dissolving Microneedle Array Patches.

The need for biocompatible polymers capable of dissolving in the skin while exhibiting reasonable mechanical features and delivery efficiency limits the range of materials that could be utilized in fabricating dissolving microneedle array patches (MAPs). The incorporation of additives, such as surfactants, during microneedle fabrication might be an alternative solution to overcome the limited range of materials used in fabricating dissolving MAPs. However, there is a lacuna in the knowledge on the effect of surfactants on the manufacture and performance of dissolving MAPs. The current study explores the role of surfactants in the manufacture and performance of dissolving MAPs fabricated from poly(vinyl alcohol) (PVA) and poly(vinyl pyrrolidone) (PVP) loaded with the model drugs, ibuprofen sodium and itraconazole. Three nonionic surfactants, Lutrol F108, Pluronic F88, and Tween 80, in solutions at varying concentrations (0.5, 1.0, and 2.0% w/w) were loaded into these dissolving MAPs. It was discovered that all of the dissolving MAPs that incorporated surfactant displayed a lower reduction in the microneedle height (≈10%) relative to the control formulation (≈20%) when subjected to a compressive force of 32 N. In addition, the incorporation of surfactants in some instances enhanced the insertion profile of these polymeric MAPs when evaluated using ex vivo neonatal porcine skin. The incorporation of surfactant into ibuprofen sodium-loaded dissolving MAPs improved the insertion depth of MAPs from 400 μm down to 600 μm. However, such enhancement was not apparent when the MAPs were loaded with the model hydrophobic drug, itraconazole. Skin deposition studies highlighted that the incorporation of surfactant enhanced the delivery efficiency of both model drugs, ibuprofen sodium and itraconazole. The incorporation of surfactant enhanced the amount of ibuprofen sodium delivered from 60.61% up to ≈75% with a majority of the drug being delivered across the skin and into the receptor compartment. On the other hand, when surfactants were added into MAPs loaded with the model hydrophobic drug itraconazole, we observed enhancement in intradermal delivery efficiency from 20% up to 30%, although this did not improve the delivery of the drug across the skin. This work highlights that the addition of nonionic surfactant is an alternative formulation strategy worth exploring to improve the performance and delivery efficiency of dissolving MAPs.

High thermal conductivity and increased thickness graphene nanosheet films prepared through metal ion-free route

With the miniaturization and integration of electronic devices heat conduction becomes a serious problem. Graphene films catch research's attention because of its excellent thermal performance and graphene oxide (GO) has been used as the most common precursor to prepare graphene films. But mostly film fabricated from GO is thinner than 30 μm and much thicker films are required to meet certain requirements. Also taking GO as raw material has many disadvantages such as the introduction of massive concentrated sulfuric acid and metal ions, huge weight loss in heat treatment and so on. Herein, we propose a new strategy to prepare graphene nanosheet films (GNFs) with a thickness of 100 μm by vacuum filtration of expand graphite through weak oxidation (WEG). Unlike common strategy, WEG without any metal ions introduced instead of GO is chosen as our raw material. The addition of nonionic surfactant and the employment of microfluidization can stabilize WEG dispersion. After graphitization at 2800 °C WEGF is transferred to GNF. The obtained 100 μm-thick film possesses a decent in-plane thermal conductivity (TC) of 760 W/mk and electrical conductivity (EC) of 5.2×10 5 S/m. Thick films with high TC can guarantee passing more heat flux and fill in larger gaps inside devices.

Effects of the Addition of Poly(ethylene Glycol) and Non-ionic Surfactants on Pretreatment, Enzymatic Hydrolysis, and Ethanol Fermentation

Effects of the Addition of Poly(ethylene Glycol) and Non-ionic Surfactants on Pretreatment, Enzymatic Hydrolysis, and Ethanol Fermentation