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Premise Methods Conclusions The extraction of high‐quality RNA is the critical first step for the analysis of gene expression and gene space. This remains particularly challenging in plants, and especially in ferns, where the disruption of the cell wall and separation of organic compounds from nucleic acids is not trivial.We developed a cetyltrimethylammonium bromide (CTAB)‐based RNA extraction protocol that consistently performs well across a large phylogenetic breadth of ferns—a lineage of plants high in secondary compounds—and in an array of tissue types. Two alternative options (precipitation vs. clean‐up without intermediate precipitation) are presented, both of which yield high‐quality RNA extracts with optical density (OD) ratios of OD 260/280 = 1.9–2.1 and OD 260/230 > 1.6, and RNA integrity numbers >7.This study presents an efficient protocol for the extraction of high‐quality RNA from multiple tissues and across the fern phylogeny, a clade of plants that still lags behind other major lineages in the development of genomic resources. We hope that this method can be used to help facilitate the closing of this gap. [ABSTRACT FROM AUTHOR]

SshEstI, a carboxylesterase from the thermoacidophilic archaeon Saccharolobus shibatae , is a member of the hormone-sensitive lipase family that displays slightly alkaliphilic activity with an optimum activity at pH 8.0. In this study, three distinct strategies were explored to confer acidophilic properties to SshEstI. The first strategy involved engineering the oxyanion hole by replacing Gly81 with serine or aspartic acid. The G81S mutant showed optimum activity at pH 7.0, whereas the aspartic acid mutant (G81D) rendered the enzyme slightly acidophilic with optimum activity observed at pH 6.0; however, k cat and k cat / K m values were reduced by these substitutions. The second strategy involved examining the effects of surfactant additives on the pH-activity profiles of SshEstI. The results showed that cetyltrimethylammonium bromide (CTAB) enhanced wild-type enzyme (WT) activity at acidic pH values. In the presence of 0.1 mM CTAB, G81S and G81D were acidophilic enzymes with optimum activity at pH 6.0 and 4.0, respectively, although their enzyme activities were low. The third strategy involved engineering the active site to resemble that of kumamolisin-As (kuma-As), an acidophilic peptidase of the sedolisin family. The catalytic triad of kuma-As was exchanged into SshEstI using site-directed mutagenesis. X-ray crystallographic analysis of the mutants (H274D and H274E) revealed that the potential hydrogen donor–acceptor distances around the active site of WT were fully maintained in these mutants. However, these mutants were inactive at pH 4–8. [ABSTRACT FROM AUTHOR]

In contrast to the conventional etching that makes nanoparticles rounder and our previous sharpening etching mode that causes serrated edges, here, we developed a new boring etching mode that targets the faces of Au nanoplates to make holes. The critical factors are the pre-incubation step with the ligand 2-mercapto-5-benzimidazolecarboxylic acid (MBIA) and the subsequent removal of excess ligands in the solution. Thus, etching is focused onto the few sites with initial loss of ligands, which cannot be quickly replaced. The choice of ligand MBIA is also of importance, as it carries negative charge and repels each other. Its inability of forming a dense layer probably plays a critical role in the site-selectivity for faces, because ligands at the higher curvature edges and corners are expected to have less repulsion. The etching results from the comproportionation reaction between Au3+ and Au0 in the nanoplates, where Br− coordination to Au and the extra stabilization from cetyltrimethylammonium bromide (CTAB) are essential. We believe that the ability of boring holes is an important tool for future synthetic designs. [ABSTRACT FROM AUTHOR]

To address the challenges of difficulty and low penetration speed of aqueous deacidification agents in paper, we aimed to enhance the wetting performance of these agents by incorporating a surfactant. We selected four surfactants for our study: anionic sodium dodecyl benzene sulfonate (SDBS), cationic cetyltrimethylammonium bromide (CTAB), nonionic polysorbate-80 (TW80), and polyether-modified trisiloxane (TRSE). The wetting properties of these surfactants on sodium propionate aqueous deacidification agent, the alkali stability of the solution, and the effects of moist heat aging on paper durability were explored. The results demonstrated that TRSE exhibited superior performance compared to the other three surfactants, effectively reducing the surface tension of sodium propionate solution to 21.02 mN/m. In alkaline conditions with a pH range of 8.00–10.00, the surface tension of SDBS, CTAB, and TW80 solutions remained stable for 30 days. Similarly, under weakly alkaline conditions with a pH value below 9, the surface tension of TRSE solutions exhibited stability. It should be noted that SDBS accelerated the decline of paper tensile index and whiteness during the heat and humidity aging process; at the same time, CTAB, TW80, and TRSE had no noticeable adverse effects on paper aging resistance. [ABSTRACT FROM AUTHOR]

Conventional perfluorooctane sulfonyl fluorosurfactants (PFOS) have caused great harm to human health and the environment, but the irreplaceable properties of fluorosurfactants offer great values. To this end, we have synthesized a highly surface active, environmentally friendly sulfonate surfactant (PBSA) with a perfluorinated branched short chain and systematically investigated its thermal stability, surface properties, wetting performance, and so forth. The minimal surface tension (γCMC) and critical micelle concentration (CMC) of the aqueous solution of PBSA were 22.70 mN/m and 0.067 mmol/L, respectively. In addition, the binary system of PBSA and cetyltrimethylammonium bromide (CTAB) exhibited excellent synergistic effects: γCMC and CMC values were reduced to 18.94 mN/m and 0.008 mmol/L. Moreover, the PBSA/CTAB mixed solution exhibited superb wetting ability: it could achieve complete wetting of PTFE plates at low concentrations (1.82 × 10−3 mol/L), with a minimum wetting concentration of only 2.84 × 10−5 mol/L. [ABSTRACT FROM AUTHOR]

The development of nanomaterials for energy storage and conversion has always been important. Layered double hydroxide (LDH) is a promising material due to its high capacity, tunable composition and easy synthesis. In this work, the morphology of NiCo‐LDH is tuned with surfactants including sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB), and investigated the correlation between morphology and electrochemical properties. NiCo‐LDH‐SDS with a layered structure exhibited a specific capacitance of 1004 C g−1 at 1 A g−1, which is higher than that of the needle‐like NiCo‐LDH‐CTAB (678 C g−1) and the rod‐like NiCo‐LDH (279 C g−1). Meanwhile, NiCo‐LDH‐SDS and NiCo‐LDH‐CTAB showed a reduction of 36 and 19 mV, respectively, in their overpotentials at 10 mA cm−2 compared to NiCo‐LDH. Contact angle and adhesive force measurements proved the influence of morphology on the interfacial properties that layered structure is favorable for the timely detachment of the bubbles. Therefore, rational morphology regulation of LDH can effectively alter the gas–liquid–solid interface and thereby accelerate the reaction kinetics. The connections between morphologies, bubbles releasing and electrochemical performance are well established in this work, which can be applied in the investigation of nanomaterials for energy‐related activities, especially the ones concerning bubbles releasing processes. [ABSTRACT FROM AUTHOR]

The goal of this work was to develop acrylonitrile–butadiene (NBR) elastomer composites filled with hydroxyapatite (HAP) characterized by improved cure characteristics and resistance to burning. Silane, i.e., (3-aminopropyl)-triethoxysilane, ionic liquid, i.e., 1-decyl-3-methylimidazolium bromide and surfactant, i.e., cetyltrimethylammonium bromide, were used to improve the filler's dispersibility in the elastomer matrix and to reduce the time and temperature of vulcanization. The effects of HAP and dispersants on the cure characteristics, crosslink density and physico–chemical properties of NBR composites were explored. The additives used, especially the ionic liquid and surfactant, effectively improved the dispersion of HAP in the NBR matrix. The amount of HAP and the dispersant used strongly affected the cure characteristics and crosslink density of NBR. The optimal vulcanization time significantly increased with HAP content and was pronouncedly reduced when ionic liquid and surfactant were applied. In addition, ionic liquid and surfactant significantly lowered the onset vulcanization temperature and improved the crosslink density and hardness of the vulcanizates while impairing their elasticity. HAP and dispersants did not significantly affect the damping properties or chemical resistance of NBR vulcanizates. Above all, application of HAP considerably enhanced the resistance of vulcanizates to thermo-oxidative aging and reduced their flammability compared with the unfilled NBR. [ABSTRACT FROM AUTHOR]

This work reports the synthesis of cationic surfactant-coated Au-Ag core-shell (Au@Ag) nanoparticles (NPs) via a straightforward seed-mediated approach. The UV-Vis analysis showed that the plasmon peak position of synthesized Au@Ag NPs correlated with the thickness of the Ag shell encapsulating the Au core. The Au@Ag NPs have shown impressive catalytic performance for the reduction reactions of 4-nitrophenol (4-NP) and methyl orange (MO) where the apparent rate constant experienced a remarkable increase by 67-fold and 90-fold, respectively, when Au@Ag NPs with the Ag-shell thickness of 6.3 nm were employed as a catalyst, compared to Au NPs. This multifold improvement in the activity cannot be simply accounted for by the increase in surface area of NPs and is attributed to the electronic synergistic effects between Au and Ag in the core-shell NPs. Furthermore, while Au@Ag NPs exhibited heightened antibacterial activity against both Gram-positive S. aureus and Gram-negative E. coli bacteria, this enhancement is modest. Notably, the anticipated significant enhancement attributed to Ag's renowned antibacterial properties was not observed. The presence of cationic surfactant cetyltrimethylammonium bromide (CTAB) enables both Au and Au@Ag NPs to effectively bind with the negatively charged bacterial cell membranes through electrostatic interactions. Apparently, CTAB enables both types of NPs to effectively target and eliminate bacteria with comparable efficiency. [ABSTRACT FROM AUTHOR]

Photocatalytic methods have been popular in energy production and environmental remediation. Designing high-efficiency photocatalysts is still challenging in converting solar energy into chemical fuels. Herein, a series of surfactant-assisted ZnIn2S4 (ZIS) photocatalysts were synthesized by utilizing the one-pot hydrothermal method. Photocatalytic methane production from an acetic acid solution was carried out under LED light (450 nm) irradiation, and the evolved gas was analyzed by the GC-FID system. Reaction factors (surfactant amount, catalyst dose, reaction temperature, substrate concentration, and reaction pH) were optimized for photocatalytic production. With the increase in cetyltrimethylammonium bromide (CTAB) amount, CH4 production gradually increased. The ZIS-3.75 photocatalyst exhibited the highest photocatalytic CH4 production rate (0.102 µmol g−1·h−1), which was approximately 1.8 times better than that of pure ZIS (0.058 µmol g−1·h−1). The presence of CTAB reduced the charge transfer resistance and improved photocurrent response efficiency. Structure and morphology were characterized by XRD, FTIR, SEM, TEM, and N2 adsorption–desorption isotherm analysis. Optical properties were investigated by UV-DRS and PL spectroscopic techniques. The electrochemical evaluation was measured through EIS, Mott–Schottky, and transient photocurrent response analysis. The CTAB-modified catalyst showed excellent stability and reusability, even after five irradiation cycles. Methane production was enhanced by lowering the photogenerated charge transfer resistance and boosting the dispersion of ZIS-3.75 under visible light (450 nm) irradiation. [ABSTRACT FROM AUTHOR]

Steam flooding is easily induced to transverse flow, with a limited swept area and low displacement efficiency. Therefore, chemical agents have been used to assist in steam flooding for heavy oil extraction. However, research into the driving mechanisms and modes of occurrence of residual oil is insufficient. In this work, a flooding simulation was conducted to understand the occurrence mechanism of residual oil during the flooding process in heavy oil reservoirs. First, the foam properties of a novel DES (Deep Eutectic Solvent) and CTAB (Cetyltrimethyl Ammonium Bromide) composite system with ultra-low interfacial tension were tested. The optimal concentration and gas–liquid ratio of the foam agent solution were determined. Secondly, the NFAS (N2 foam-assisted steam flooding) was carried out after steam flooding, and the flow behavior of crude oil at different flow pathway zones was researched. In the end, the remaining oil morphology and distribution characteristics under different displacement times were analyzed, determining the mode of remaining oil occurrence during NFAS flooding. The results show that (1) the novel DES and CTAB system has good foam properties. The best concentration is 0.5 wt%, and the optimal ratio of gas to liquid is 1:1. (2) In the steam flooding stage, the columnar remaining oil in the narrow hole near the flow pathway increases, and the cluster remaining oil in the far flow channel changes into film and columnar. (3) During NFAS displacement, the residual oil primarily presents a state of fully mixing the O/W emulsion formed after blending and dispersing with oil, gas, and water. (4) After the NFAS flooding stage, the remaining oil was distributed in each throat. The remaining oil in the near passage is mostly blocked by foam in large holes with a pore coordination number of 4 and 5. The residual oil in the distant runner is distributed in the thick and middle throats. (5) NFAS flooding outperforms steam flooding by significantly decreasing residual oil in narrow passages of the main flow channel and near flow channels, resulting in a substantial 44.9% increase in overall recovery rate. [ABSTRACT FROM AUTHOR]

The preparation of spherical-like battery-grade ferric phosphate by co-precipitation--spray-drying method was investigated using ferrous sulfate heptahydrate (FeSO4, • 7H2O) and ammonium dihydrogen phosphate (NH4 H2 PO4) as raw materials. The effects of the addition of the surfactant cetyltrimethyl ammonium bromide (CTAB), reaction time, and solution pH on the physical phase and particle size of ferric phosphate were examined. The products were characterized by a laser particle sizer, X-ray powder diffractometer, thermogravimetric analyzer, and field emission scanning electron microscope. The results indicate that under the conditions of a Fe/P molar ratio of 1/1.01, CTAB addition of 0.04 g, reaction time of 1 h, and solution pH of 3.0, the ferric phosphate exhibits the smallest particle size distribution, ranging from 300 to 500 nm, and displays more uniform spherical morphology. Moreover, lithium iron phosphate is prepared by ball milling, mixing and sintering, using the spherical-like ferric phosphate as the precursor iron source. The specific discharge capacity of lithium iron phosphate is 150.14 mAh/g at 0.1 C and the retention rate is 98.9% after 200 cycles at 1 C, the performance is good. [ABSTRACT FROM AUTHOR]

Secondary caries is one of the main reasons for dental filling replacement. There is a need to obtain dental restorative material that is able to act against caries-inducing microorganisms. This study explores the antimicrobial properties of cetyltrimethylammonium bromide (CTAB) or dimethyldioctadecylammonium bromide (DODAB)-modified photo-cured experimental dental composites against Escherichia coli, Streptococcus mutans, and Candida albicans. The antimicrobial activity against Escherichia coli, Streptococcus mutans, and Candida albicans was assessed by using an Accuri C6 flow cytofluorimeter, and then analyzed using BD CSampler software (1.0.264). Bacterial/yeast surface colonization was carried out by using an GX71 inverted-optics fluorescence microscope equipped with a DP 73 digital camera. For bactericidal surface analysis of each sample type, simultaneous standardization was performed using a positive control (live cells) and a negative control (dead cells). A positive correlation between the increasing concentration of CTAB or DODAB and the dead cell ratio of Escherichia coli, Streptococcus mutans, and Candida albicans was revealed. In particular, CTAB at a 2.0 wt% concentration exhibits superior efficiency against pathogens (65.0% dead cells of Escherichia coli, 73.9% dead cells of Streptococcus mutans, and 23.9% dead cells of Candida albicans after 60 min). However, Candida albicans is more resistant to used salts than bacteria. A CTAB- or DODAB-modified experimental dental composite exhibits antimicrobial potential against Escherichia coli, Streptococcus mutans, and Candida albicans after 10 and 60 min of incubation, and the antimicrobial efficiency increases with the wt% of QAS in the tested material. [ABSTRACT FROM AUTHOR]

Nanosized Cu–Mn composite oxide catalysts were prepared from potassium permanganate, copper nitrate, n-butanol, and cetyltrimethylammonium bromide as a manganese source, copper source, reducing agent, and surfactant, respectively. The Cu0.2–Mn sample possessed a small particle size (10–40nm) and a relatively high specific surface area (46.24m2 ⋅g−1); its main components were Cu1.5Mn1.5O4 and Mn3O4. As a consequence, the Cu0.2–Mn catalyst exhibited good catalytic activity in the oxidation of toluene. At a toluene concentration of 1000ppm and a space velocity of 60,000mL ⋅g−1 ⋅h−1, the T50 and T90 of the Cu0.2–Mn catalyst toward toluene were 239∘C and 250∘C, respectively. Furthermore, even after 30h of operation at 275∘C, the conversion of toluene was 99% (at the space velocity of 60,000mL ⋅g−1 ⋅h−1). [ABSTRACT FROM AUTHOR]

Cupriavidus necator, despite lacking direct electron transfer capabilities, demonstrates efficient reduction of various redox mediators in oxygen‐free cultivation within bioelectrochemical systems. This study investigates the reduction site of ferricyanide through inhibition and expression rate analysis of oxygen and nitrate respiration chain complexes, comparing aerobic cultivation conditions with fructose as carbon and electron donor to autotrophic (CO2/H2/O2) and anodic cultivation conditions (fructose/anode). Azide inhibition identified cytochrome c oxidase as the primary complex facilitating electron transfer to ferricyanide, with a secondary role proposed for nitrite reductase NirS, demonstrating a 3.9±1.1‐fold higher expression when exposed to anodic conditions. The 2.9±0.6‐fold increase in the expression of the natural porin OmpA under anodic conditions implies its potential involvement in ferricyanide uptake. Additionally, chemically permeabilizing cell membranes with cetyltrimethylammonium bromide doubles ferricyanide reduction rates without an anode present, offering insights for optimizing redox mediation in C. necator based bioelectrochemical systems. This study opens up new possibilities for the targeted optimization of mediated electron transfer in C. necator and other organisms. [ABSTRACT FROM AUTHOR]

This study aims to enhance the performance of inorganic perovskite light‐emitting diodes (PeLEDs) by incorporating porous silica (p‐SiO2) to fabricate perovskite‐composite films for electroluminescence (EL) devices. This is because, in addition to the inorganic perovskite material, composites with inherently stable materials are needed for perovskite to ensure additional external stability. The introduced p‐SiO2 particles impede the crystal growth of perovskite during the anti‐solvent assisted crystallization process, resulting in the formation of smaller CsPbBr3 crystals in the CsPbBr3/p‐SiO2 composite film. Accordingly, compared to previous CsPbBr3 films, this composite film exhibits two folds with higher photoluminescence quantum yield (PLQY) due to improved crystalline formation. Surprisingly, the CsPbBr3/p‐SiO2 composite film additionally has good water‐resistant properties because the residual cetyltrimethylammonium bromide (CTAB) molecules are extracted from the p‐SiO2 particles and are oriented at the top surface of the CsPbBr3/p‐SiO2 composite film. The EL device fabricated with this composite film exhibits outstanding luminescence efficiency, with a current efficiency (CE) of 70.06 cd A−1 and an external quantum efficiency (EQE) of 16.97%, surpassing control samples by two folds of magnitude. Furthermore, the operational stability improves approximately sevenfold compared to the control, presenting a promising strategy for advancing the field of inorganic perovskite ELs. [ABSTRACT FROM AUTHOR]

This research studied the effect of electrolyte composition NaCl, Na2SO4 and CTAB (cetyltrimethylammonium bromide, C19H42BrN) on the electrochemical synthesis of Cu2O nanoparticles. The NaCl concentration was varied in three levels of 58.5, 117 and 175.5 (g/L); the Na2SO4 concentration was changed in three levels of 24, 32 and 48 (g/L) and the CTAB concentration was adjusted in four levels of 2, 4, 6 and 15 (g/L). The current density and temperature were kept constant at 0.4 (A/cm2) and 70 °C, respectively and the cathode-anode distance was set at 2.5 cm. The morphology, composition, particle size and distribution of the samples were examined by FESEM, XRD and DLS. The results indicated that increasing the concentration of electrolyte NaCl and Na2SO4 enhanced the purity of Cu2O. The Cu2O crystals were smaller than 100 nm and formed as polycrystalline. Moreover, higher concentration of NaCl than Na2SO4 led to a better result. CTAB effectively inhibited the growth of Cu2O nanoparticles and the particle size decreased with increasing CTAB. The optimal result was achieved in the sample with 4 (g/L) CTAB and 175 (g/L) NaCl. Cu2O nanoparticles with high purity and crystal size of 27.87 nm were produced. [ABSTRACT FROM AUTHOR]

The influence of micellar systems based on cationic surfactants—gadolinium(III) and copper(II) complexes with alkylated 1,4-diazabicyclo[2.2.2]octane, 1-hexadecyl-4-aza-1-azoniabicyclo[2.2.2]octane bromide (ligand) and the conventional surfactant cetyltrimethylammonium bromide – on the solubility of the antimalarial drug artemisinin in water was studied by spectrophotometric method. A quantitative assessment of the solubilizing ability of surfactant aggregates was carried out. The value of the solubilization capacity of the systems was determined. The ligand has the greatest influence on the solubility of artemisinin, and, consequently, its bioavailability. The concentration of the drug increases up to 36 times in the presence of a relatively low surfactant content in the aqueous solution. The period of chemical stability of artemisinin in cationic surfactants solutions was determined. Aggregates formed in surfactant-artemisinin systems were characterized by dynamic and electrophoretic light scattering. [ABSTRACT FROM AUTHOR]

Microalgae are a valuable source of lipids, proteins, and pigments, but there are challenges in large-scale production, especially in harvesting. Existing methods lack proven efficacy and cost-effectiveness. However, flocculation, an energy-efficient technique, is emerging as a promising solution. Integrating surfactants enhances microalgal harvesting and disruption simultaneously, reducing processing costs. This study investigated cetyltrimethylammonium bromide (CTAB), dodecyltrimethylammonium bromide (DTAB), and sodium dodecyl sulphate (SDS) for harvesting Tetraselmis sp. strains (75LG and 46NLG). CTAB exhibits superior results, with 88% harvesting efficiency at 1500 and 2000 mg L−1 for 75LG and 46NLG, respectively, for 60 min of sedimentation—thus being able to reduce the operating time. Beyond evaluating harvesting efficiency, our study explored the kinetics of the process; the modified Gompertz model led to the best fit. Furthermore, the largest kinetic constants were observed with CTAB, thus highlighting its efficacy in optimising the microalgal harvesting process. With the incorporation of the suggested enhancements, which should be addressed in future work, CTAB could hold the potential to optimise microalgal harvesting for cost-effective and sustainable large-scale production, eventually unlocking the commercial potential of microalgae for biodiesel production. [ABSTRACT FROM AUTHOR]

Surfactant-stabilized CO2 foam is a promising technology to reduce CO2 mobility in geologic CO2 storage and CO2 enhanced oil recovery processes. In this study, various combinations of a non-ionic surfactant, Alkyl polyglycoside, along with cationic surfactants were ingeniously examined to enhance carbon storage and facilitate oil recovery through CO2- based foam flooding. Specifically, for the first time, the investigation focused on the impact of altering the alkyl chain length and counter-ion type of the cationic surfactants. The surfactant combinations were first screened based on surfactant characterization, surface and interfacial tension studies and bulk foam experiments. The interfacial tension studies showed that, in combination with Alkyl polyglycosides, the C16 (cetyltrimethylammonium bromide and cetyltrimethylammonium chloride) alkyl chain length cationic surfactants exhibited less interfacial tension values than the C12 (dodecyltrimethylammonium bromide and dodecyltrimethylammonium chloride) alkyl chain length cationic surfactant. The bulk foam experiments established that Alkyl polyglycosides/C16 combination showed higher foamability and foam stability than Alkyl polyglycosides/C12 combination. The bulk foam investigation showed that the optimized concentration of Alkyl polyglycosides/cationicsurfactant was 0.3/0.15 wt%. The surfactant combinations screened from these studies were evaluated for EOR coreflooding experiments at 1250 psi and 60 ◦C. The incremental oil recovery obtained for baseline CO2 and Alkyl polyglycosides/cetyltrimethylammonium bromide foam flooding was 18.5% and 32.7%, respectively. The estimated carbon storage potential for baseline CO2 g and Alkyl polyglycosides/cetyltrimethylammonium bromide foam flooding was 11.9% and 23.7%, respectively. The combination of Alkyl polyglycosides cetyltrimethylammonium bromide surfactant was demonstrated as an effective solution for increased oil recovery and carbon storage. [ABSTRACT FROM AUTHOR]

Current research of triplet–triplet annihilation upconversion (TTA-UC) faces difficulty such as overuse of organic solvents and quenching of excited triplet sensitizers by molecular oxygen. Herein, we propose an efficient and facile preparation strategy of TTA-UC microemulsion to overcome these issues. With simple device and short preparation process, air-stable TTA-UC with a high upconversion efficiency of 16.52% was achieved in microemulsion coassembled from TritonX114, tetrahydrofuran and upconverting chromophores (platinum octaethyl-porphyrin and 9,10-diphenylanthracene). This is comparable to the highest UC efficiency ever reported for TTA-UC microemulsion systems. The excellent UC performance of TX114–THF could be attributed to two perspectives. Firstly, small-size micelle accommodated chromophores up to high concentrations in organic phase, which promoted efficient molecular collision. Additionally, high absorbance at 532 nm ensured full use of excitation light, getting more long wavelength photons involved in the TTA-UC process. Moreover, air-stable TTA-UC also performed well in microemulsion with various surfactants, including nonionic surfactants (Tween 20, Tween 80, Triton X-110, Triton X-114), ionic surfactants (sodium dodecyl sulfate, cetyltrimethyl ammonium bromide) and block copolymers (pluronic F127, pluronic P123), through three conjectural assembly models according to the structural characteristics of surfactant molecules (concentrated, uncompacted and scattered). These discoveries could provide estimable reference for selection of surfactants in relevant fields of TTA-UC. [ABSTRACT FROM AUTHOR]

This research focused on harnessing amino‐functionalized montmorillonite (Mt) clay, achieved through the grafting of [3(2‐aminoethyl)amino]propyltrimethoxysilane (AEP‐TMS), as carbon paste electrode (CPE) modifier for the electroanalysis of ciprofloxacin (CF). The characterization of both Mt and the amino‐functionalized (Mt‐NH2) materials was carried out using various techniques including Fourier‐transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X‐ray diffraction (XRD). Afterwards, various CPEs modified using Mt and Mt‐NH2 were prepared and characterized employing SEM‐energy dispersive X‐ray (EDX), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). By EIS, Mt‐NH2‐CPE exhibited significantly faster electron transfer with lower charge‐transfer resistance (438.5 Ω) compared to Mt‐CPE (3572.1 Ω) and to the bare CPE (2066.1 Ω). Additionally, CV experiments performed by using redox probes demonstrated the excellent accumulation capability of [Fe(CN)6]3− ions on Mt‐NH2‐CPE surface. The Mt‐NH2‐CPE was subsequently applied using square wave voltammetry to determine CF in the presence of cetyltrimethylammonium bromide (CTAB), yielding an impressive linear range from 30 to 240 μM (R=0.999) and a low detection limit of 0.07 μM (23.2 μg L−1). The method exhibited stable and reproducible responses (RSD=3.25 %; n= 6) under optimized conditions. Following interference studies, the optimized method was effectively applied to quantify CF concentrations in pharmaceutical and water samples. [ABSTRACT FROM AUTHOR]

Herein, the interface of Nb 2 CT x @MoSe 2 heterojunction could be easily regulated by CTAB. The intimate contact of Nb 2 CT x /MoSe 2 not only facilitate electron/ion transport, but also assure the integrity of the hybrid electrode. As excepted, the capacity (406 mA h/g) retention is 80% from 100 to 1000 mA/g concerning rate performance. [Display omitted] Exploring robust electrode materials which could permit fast and reversible insertion/extraction of large K+ is a crucial challenge for potassium-ion batteries (PIBs). Smart interfacial design could facilitate electron/ion transport as well as assure the integrity of electrode. Herein, Cetyltrimethylammonium bromide (CTAB) was found to play bifunctional roles in construction of Nb 2 CT x @MoSe 2 heterostructure. Firstly, functionalization of CTAB on the surface of Nb 2 CT x could influence the subsequent growth of MoSe 2 by electrostatic effect, stereochemical effect and the synergetic Lewis acid-base interaction, leading to the formation of Nb 2 CT x @MoSe 2 with tiled heterostructure. Secondly, the interlayer spacing of Nb 2 CT x was expanded from 0.77 to 1.21 nm owing to the pillar effect of CTAB. As excepted, the capacity retention was 80 % from 100 mA g−1 (406 mA h g−1) to 1000 mA g−1 concerning rate capability and the specific capacity maintained at 240 mA h g−1 (at 2000 mA g−1) over 300 cycles. The calculated D K values from Galvanostatic intermittent titration technique (GITT) measurement of the titled C-T-Nb 2 CT x @MoSe 2 @C electrode is two orders of magnitude larger than the traditional T-Nb 2 CT x @MoSe 2 @C electrode, further confirming intimate interface between MoSe 2 and Nb 2 CT x could provide convenient potassium-ion transport channels and fast diffusion kinetics. Finally, ex-situ characterizations at different charging and discharging voltage stages, including ex-situ XRD/Raman/HRTEM/XPS have been carried out to reveal the potassium storage mechanism. This work provides a facile strategy for the regulation of interface engineering by the assist of CTAB which could extend to other MXenes-TMDs (Transition metal dichalcogenides) hybrid electrodes. [ABSTRACT FROM AUTHOR]

In this study, pristine silver-doped zinc oxide (Ag–ZnO) and Plumbago zeylanica leaf extract (PZE) incorporated with Ag–ZnO, along with the additional material of cetyltrimethylammonium bromide (CTAB)-assisted Ag–ZnO nanorods, were synthesized and extensively characterized. The basic properties of the samples were studied and optimized. Gas sensing measurements were conducted, and the obtained results were thoroughly interpreted. The study includes demonstrating and examining pure Ag–ZnO, PZE-added Ag–ZnO, and CTAB-assisted Ag–ZnO. Notably, the presence of CTAB exhibited a favorable effect on the Ag–ZnO, indicating an enhanced isopropyl alcohol gas sensing response time of 20 s at 15 ppm within an ambient temperature. Additionally, improvements in selectivity and reduced sensor resistance in current (nanoampere - nA) were observed in CTAB-assisted Ag–ZnO. The sensing mechanism was investigated, focusing on the depletion layer of Ag–ZnO with the surfactant. The work emphasizes the sensing abilities of PZE-assisted Ag–ZnO and CTAB Ag–ZnO, highlighting the significance of these noble metals in systematic gas sensing applications. [ABSTRACT FROM AUTHOR]

The kinetics of Os(VIII) accelerated L-Leucine (L-Leu) oxidation in cetyltrimethylammonium bromide (CTAB) by hexacyanoferrate(III) [HCF(III)] was investigated by registering the decline in absorbance at 431 nm. Employing the pseudo-first-order condition, the reaction's advancement has been examined as an indicator of [CTAB], [Os(VIII)], [OH−], [L-Leu], [HCF(III)], temperature, and ionic strength. The results show that [OH−], [CTAB], and [L-Leu] are the critical parameters with a discernible influence on reaction rate. L-Leu interacts with HCF(III) in a 1:2 ratio. The rate constant is independent of the [HCF(III)] and is merely used up to regenerate the Os(VIII) during the reaction. In the investigated concentration ranges of Os(VIII), [OH−], and [L-Leu], the reaction demonstrates first-order kinetics, but follows less than unit order at higher concentrations of L-Leu (more than 6.0 × 10−3 mole dm−3) and alkali (more than 0.4 mole dm−3). A positive salt effect is indicated by the linear rise in reaction rate with additional electrolytes. CTAB catalyzes the process substantially, and once at its peak at 7.0 × 10−4 mole dm−3, the rate remains constant as [CTAB] grows up to 8.5 × 10−4 mole dm−3. With anionic surfactant sodium dodecyl sulfate, the reaction rate was significantly reduced even in the presence of Os(VIII). Reduced repulsion between surfactant molecule's positive charge heads brought on by the negative-charged HCF(III), OH−, and [OsO5(OH)]3− molecules may be responsible for the witnessed drop in CTAB critical micellar concentration (CMC). [ABSTRACT FROM AUTHOR]

The permanganate–H2SO4 redox reaction, useful in oxidative treatments under aqueous conditions, was studied spectrophotometrically in the absence and presence of cetyltrimethylammonium bromide (CTAB). The decolorization reactions were influenced by the [MnO4−], [H2SO4], and temperature. Permanganate reduction follows first‐, and complex–order kinetics with permanganate, and H2SO4 concentrations, respectively. The reduction of permanganate (Mn(VII)) proceeds through a complex formation between MnO4− and H2SO4. The characteristic absorption peaks for MnO42− (λmax = 439 and 606 nm), MnO43− (λmax = 667 nm), and MnO2 (λmax = 400–418 nm) were not appeared during the redox reaction. The KMnO4 degradation efficiency remains unaffected with sodium pyrophosphate and sodium fluoride. The results of this study demonstrated the formation of Mn(II) as the stable product in acidic reaction media. The degradation efficiency increases drastically from 15 to 100% with 2.0 × 10−4 to 16.0 × 10−4 mol/L CTAB concentration under sub‐, and post‐micellar reaction conditions, respectively. The thermodynamic parameters (activation energy = 98.8 and 43.2 kJ/mol), activation of enthalpy (96.3, and 39.0 kJ/mol), activation of entropy (16.2 and −149.5 J/K/mol), free energy of activation (93.1 and 83.5 kJ/mol) were calculated without and with CTAB, respectively. Hence, CTAB can be exploited for its multifunctional applications, and specifically for the catalytic role in the permanganate‐assisted redox reactions in future. [ABSTRACT FROM AUTHOR]

The tailoring of the surface properties of cellulose nanocrystals (CNCs) to meet various requirements in environmental, food, and material areas has always been of great interest. In this study, the surface chemistry of CNCs was noncovalently modified by cetyltrimethylammonium bromide (CTAB), followed by characterizations and an investigation into its application as a coating material for interfacial interaction over various substrates. Due to the CTAB modification, the surface charge of the CNCs was neutralized, resulting in an increased size of each nanocrystal at the aqueous status and the aggregated microfibers when dried up. The CTAB modification not only decreased the crystallinity of the samples from 48.57% to 9.12%, but also reasonably hydrophobized the CNCs and decreased their total surface energy. Finally, the adsorption behavior of the CNCs and CTAB-CNCs over nonionic, anionic, and cationic polymers was investigated by ellipsometry. Based on the thickness of the CNC and CTAB-CNC layers over 2-Hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC), and polyethyleneimine (PEI), we proposed that the adsorption behavior was overall influenced by electrostatic interaction, hydrogen bonding, and van der Waals forces, and the thickness of the adsorbed layers could be impacted by both the surface charge and the size of the crystals.

The reduction kinetics of N,N′-phenylenebis(salicylideneiminato)iron(III), [Fe(salphen)]+ by thioglycolic acid (TSH) has been carried out in mixed aqueous medium (DMSO:H2O; 1:4) in pseudo-first order condition at 26 ± 1 °C. A CORNING colorimeter 253 was used to monitor the reaction rates by detecting the absorbance reduction of the reaction at 435 nm. The reaction was acid independent, second order overall and demonstrated zero Brønsted-Debye salt effect. Ions such as Mg2+ and CH3COO- catalyzed the reaction. The thermodynamic parameters indicated an activated complex that is much ordered and a highly solvated transition state. Reaction catalysis was observed in the case of sodium dodecylsulphate (SDS) and cetyltrimethylammonium bromide (CTAB) inclusion. The critical micelle concentrations obtained for SDS were 8.0 × 10−3 and 3.3 × 10−3 mol dm−3 whereas that observed for CTAB were 2.0 × 10−3 and 2.8 × 10−3 mol dm−3 in water and [Fe(salphen)]+ reaction media respectively. Piszkiewicz model was used to analyze the results which indicated the existence of pre-micellar aggregates and significant electrostatic and hydrophobic interactions between the metal complex and the pre-micellar aggregates of the surfactants. The cooperativity index and binding constants obtained were n = 1.22, K = 4.78 × 104 dm3 mol−1, n = 1.27 and K = 4.55 × 104 dm3 mol−1 respectively for SDS and CTAB. A plausible mechanism suggesting an outer-sphere mechanism has been postulated. [ABSTRACT FROM AUTHOR]

Hollow SiO 2 microspheres have become attractive materials for nanotechnology applications owing to their biological inertness and high functionality. In this study, hydrophobic spherical hollow cages were formed using the soft stencil method with Pluronic F127 and cetyltrimethylammonium bromide (CTAB) as the structure-directing agent, and hollow nanoporous SiO 2 microspheres (FHMS) were prepared using the soft template method. Various of amine functionalization modes were further employed to demonstrate the complexity of the relationship between pore structure/amidation mode/amine content and adsorption capacity. The hollow morphology of the porous silica was revealed using field-emission scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and its porous properties were revealed using nitrogen adsorption-desorption isotherm measurements. Experiments on the fixed-bed dynamic adsorption process at 15% CO 2 showed that the high specific surface area, high pore volume and amine content of the carriers had a positive effect on the adsorption performance. However, the accessibility of the adsorption centre was affected at high loadings, and the amine efficiency and adsorption capacity were reduced. The dual amine functionalized FHMS-G-I60 maintained the integrity and order of the hollow mesoporous carrier structure, and overcame the dilemma of easy loss in the cycle process of the impregnation method and the low adsorption capacity of the grafting method. It possessed an adsorption capacity of 3.62 mmol/g, high adsorption cycling stability (more than 99.5% adsorption maintained after 10 cycles) and high amine efficiency (0.2852 mmol CO 2 /mmol N). CO 2 -TPD analysis (Thermal Programmed Desorption) further showed that FHMS-G-I60 had a faster desorption rate and lower regeneration energy consumption. In general, such structure-directed prepared matrices and functionalized with different amines are promising and low-cost adsorbents that can be used to capture CO 2 from ambient air and flue gases under different demands. [ABSTRACT FROM AUTHOR]

The sensor, designed to be worn directly on the skin, is suitable for real-time monitoring of the recovery level of not only general wounds, but also difficult-to-heal wounds, such as those with chronic inflammation. Notably, healthy skin has a pH range of 4–6. When a wound occurs, the pH is known to be approximately 7.4. In this study, alpha-naphtholphthalein (Naph) was immersed in a cotton-blended textile to produce a wearable halochromic sensor that clearly changed color depending on the pH of the skin in the range 6–9, including pH 7.4, which is the skin infection state. The coating was performed without using an organic solvent by dissolving it in micelle form using cetyltrimethylammonium bromide, a surfactant, in water. Naph-based halochromic sensor shows light yellow, which is the dye's own color, at pH 6, which is a healthy skin condition, and gradually showed a clear color change to light green-green-blue as pH increased. Even after washing and drying by rubbing with regular tap water, the color change due to pH was maintained more than 10 times. Naph-based halochromic sensors use a simple solution production and coating method and are not only reusable sensors that can be washed with water but also use environmentally friendly water, making them very suitable for developing commercial products for wound pH monitoring. In addition, it can be easily applied to medical supplies, such as medical gauze, patient clothes, and compression bandages, as well as everyday wear, such as clothing, gloves, and socks. Therefore, it is expected to be widely used as a wound pH sensor, allowing real-time monitoring of the skin condition of individuals with chronic skin inflammation, including patients requiring wound recovery. [ABSTRACT FROM AUTHOR]

This study used a hydrothermal approach to create porous ZnO nanoparticles with the help of glucose (Glu), cetyltrimethylammonium bromide (CTAB), and polyvinylpyrrolidone (PVP). The morphological characterization revealed some small pores on the surface of the samples, all of which were in the 10–20 nm pore size range. The gas test revealed that the Glu‐ZnO material performed best for acetone at 120 °C, with a response value of 82 for 100 ppm, which was approximately ten times for that of pure ZnO (8.6), and the response/recovery time was also twice as short. [ABSTRACT FROM AUTHOR]

The aim of this work is to develop a simple, sensitive, and reliable colorimetric test method for the visual detection of Fe(II) and Fe(III) in water. The sample solution of Fe(III) was initially complexed with chromeazurol S (CAS) followed by ion-pair association with cetyltrimethylammonium bromide (CTAB) in the presence of perchlorate ions. This led to the formation of a bulky and insoluble fluffy precipitate involving the physical entrapment of the ternary complex of Fe-CAS-CTAB, which floats on the top of the solution. Depending on the concentration of Fe(III), this type of ternary complex produces an impressive color change from reddish magenta to purple and then to cyan-blue, easily detectable with the naked eye without the need for expensive instrumentation. The ternary-colored complex was formed instantly and remained stable for at least 8 h with constant absorbance. For the determination of total iron and Fe(II), complete oxidation of Fe(II) to Fe(III) was carried out using 100 μL of KMnO4 (0.005%). The minimal response with the test method was found to be about 5 ng/mL of Fe(III) in 2 min of the total sample testing procedure. However, Fe(III) could be quantified using a spectrophotometer after dissolving the fluffy precipitate in toluene solvent. The calibration graph was linear in the range of 5–30 ng/mL of Fe(III) with a correlation coefficient of 0.9931 and a limit of detection of 0.9 ng/mL. The relative standard deviation was found to be less than 6%. At the end of the study, the efficacy of the method was evaluated by its application to groundwater and thermal power plant coolant waters. [ABSTRACT FROM AUTHOR]

Objective: Staphylococcus aureus, a severe public health hazard, causesfoodborne diseasesfrom the consumption of contaminated food. Various antimicrobials and disinfectants are used throughout the food chain to reduce microbial contamination or eliminate microorganisms on food contact surfaces. However, little is known about the susceptibility of disinfectants to food pathogens, including S. aureus, which can develop resistance to antimicrobials and cause severe diseases. Materials and Methods: The antimicrobial activity of triclosan, cetyltrimethylammonium bromide (CTAB), acetic acid, citric acid, and lactic acid against 50 S. aureus isolates, including multidrug-resistant (MDR) isolates originating from ground beef, chicken, and fish, was investigated using the broth microdilution method. Results: The minimal inhibitory concentrations (MICs) of triclosan, CTAB, acetic acid, citric acid, and lactic acid against the isolates were 0.125-16 μg/mL, 0.25-32 μg/mL, 102.5-26250 μg/mL, 187.5-12000 μg/mL, and 703-22500 μg/mL, respectively. Almost all MDR isolates showed resistance to triclosan. There was a statistically significant difference in MICs between triclosan and organic acids, as well as between CTAB and organic acids (p < 0.05). However, a statistically significant difference was not observed in triclosan and CTAB, as well as in acetic acid and lactic acid (p > 0.05). Pearson correlation coefficient revealed a strong relationship between triclosan and multidrug resistance. Based on the multiple linear regression analysis, triclosan had a positive effect on multidrug resistance (p < 0.05). Conclusion: This research gives helpful information on the susceptibility of disinfectants to S. aureus, particularly to resistant S. aureus isolates from meats, which may help to recommend proper disinfectant use in food production. [ABSTRACT FROM AUTHOR]

Herein, orderly arranged bamboo-like mesoporous silica materials were prepared using cetyltrimethylammonium bromide (CTAB) as the template and n-hexanol as the long-chain alcohol cosurfactant. The ordered meso-structure was characterized by XRD analysis, field emission scanning electron microscopy (FE-SEM, Hitachi S4800), transmission electron microscopy, BET and IR spectroscopy analysis. The effects of the CTAB/n-hexanol molar ratio(R), length of the hydrophobic chain with a terminating hydroxyl group on the long-chain alcohol cosurfactant, parity of the hydrophobic carbon atoms on the surface topography, specific surface area, and pore size of the powder were investigated. The results showed that when the molar ratio = 1, the mesoporous silica presented neatly arranged bamboo segment lengths of 19.6–23.9 μm, platycodon grandiflorum widths of 2.13–3.32 μm, pore size of 3.04 nm, and surface area of 820.034 m2/g. Increasing or decreasing the amount of n-hexanol directing led to denser or looser lateral molecular interactions between CTAB and the co-structure-directing agents that respectively reduced or increased the pore size, with the latter resulting in the formation of spherical particles. When n-hexanol was replaced by n-heptanol or n-octanol, the pore size and surface area of the mesoporous silica decreased significantly with the increase in the hydrophobic chain length. [ABSTRACT FROM AUTHOR]

The tailoring of the surface properties of cellulose nanocrystals (CNCs) to meet various requirements in environmental, food, and material areas has always been of great interest. In this study, the surface chemistry of CNCs was noncovalently modified by cetyltrimethylammonium bromide (CTAB), followed by characterizations and an investigation into its application as a coating material for interfacial interaction over various substrates. Due to the CTAB modification, the surface charge of the CNCs was neutralized, resulting in an increased size of each nanocrystal at the aqueous status and the aggregated microfibers when dried up. The CTAB modification not only decreased the crystallinity of the samples from 48.57% to 9.12%, but also reasonably hydrophobized the CNCs and decreased their total surface energy. Finally, the adsorption behavior of the CNCs and CTAB-CNCs over nonionic, anionic, and cationic polymers was investigated by ellipsometry. Based on the thickness of the CNC and CTAB-CNC layers over 2-Hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC), and polyethyleneimine (PEI), we proposed that the adsorption behavior was overall influenced by electrostatic interaction, hydrogen bonding, and van der Waals forces, and the thickness of the adsorbed layers could be impacted by both the surface charge and the size of the crystals. [ABSTRACT FROM AUTHOR]

The interaction of cetyltrimethylammonium bromide (CTAB) with orange II has been studied spectrophotometrically. CTA‐Orange II complex was isolated from an aqueous solution with chloroform. The results indicate that the CTAB interacts in 1:1 stoichiometry with orange II. CTAB capped FeNPs were used as an adsorbent to the removal of CTA‐Orange II complex. Energy dispersive x‐ray spectroscope (EDX), Fourier transform infrared spectroscope (FTIR), surface scanning microscope (SEM), and transmission electron microscope (TEM) were used to determine the morphology of FeNPs. The effect of contact time, pH, and concentration of orange II were examined on the removal of dye and surfactant. The removal of orange II followed pseudo‐second‐order kinetic and Langmuir isotherm model. The maximum adsorption capacity (Qmax) of CTAB‐FeNPs for orange II was 1288.9 mg/g at 30°C. CTA‐Orange II complex was adsorbed onto the adsorbent through several types of interaction (e.g., electrostatic attractions, van der Waals interactions, hydrogen bonding and n‐π stacking interactions). The sorption of orange G was also studied at different CTAB concentrations. The results implied that the maximum sorption amount was almost half of the orange II adsorption. The findings reveal the feasibility of CTAB capped FeNPs to be used as an excellent and low‐cost adsorbent for the removal of various water pollutants, more specifically anionic dyes. [ABSTRACT FROM AUTHOR]

Excellent mechanical strength and biodegradable characteristics of magnesium alloys have sparked considerable interest in orthopedic applications. The utilization of magnesium alloys in orthopedic applications has been restricted due to their brittleness caused by high corrosion rate in biological environments. One of the best techniques for increasing corrosion resistance of these alloys is surface coating. For the first time, the present work aims to dip-coat zein-bioactive glass (BG) nanocomposite on AZ31B magnesium alloy. The alloy surface was also coated by native zein as a control coating. BG nanoparticles required for zein and BG (zein_BG) composite were synthesized by a bio-inspired method using cetyltrimethylammonium bromide (CTAB) as a template. The formation of BG particles was affirmed by FTIR showing characteristic Si-O-Si and Si-O– peaks. Nano-size of BG particles with an average diameter of 6.67 ± 0.06 nm was reported by TEM. SEM micrographs revealed successful deposition of zein and zein_BG coatings on the magnesium alloy surfaces. High-resolution XPS analysis on zein_BG-coated Mg alloy immersed in HBSS revealed the corrosion deposition of Mg(OH)2, MgHPO4.H2O, CaHPO4.H2O, SiO2, MgCO3, and CaCO3 on the substrate surface. More than twofold wettability, 95% adhesion strength and 14-fold increase in surface roughness were reported for zein_BG-coated magnesium alloy compared to the bare surface. Measurements of weight loss in zein and zein_BG-coated alloy substrates in Hanks Balanced Salt Solution (HBSS) for 10 d at 37°C showed a drastic decrease in weight loss of substrates after coating. As a result, zein_BG-coated substrate was observed to possess the maximum protective efficacy (95.99%) against corrosion. Interestingly, electrochemical measurements revealed a vast decrease in corrosion current density (2.41 E−6 A.cm−2) of zein_BG-coated substrate compared to the uncoated substrate (3.04 E−4 A.cm−2). Electrochemical impedance spectra (EIS) confirmed capacitive behavior of zein_BG-coated alloy substrate. These findings demonstrated that simple zein_BG composite dip coating was a successful corrosion-resistant implant coating on magnesium alloy surface for orthopedic applications. [ABSTRACT FROM AUTHOR]

Ag@SiO2 core–shell nanoparticles (NPs) have attracted extensive attention for their excellent surface-enhanced Raman scattering (SERS)-fluorescence (SEF) and their potential applications in sensing, biomedicine, and imaging. The thickness of silica shell plays a crucial role in determining the SERS-SEF properties. However, a few studies have been made to synthesize Ag@SiO2 core–shell NPs with controllable thickness of silica shell and systematic research about the optimized SERS-SEF enhancement. Here, Ag@SiO2 core–shell NPs were prepared by a modified one-pot synthetic method via reducing AgNO3 using formaldehyde in the presence of cetyltrimethylammonium chloride and sequentially hydrolyzing tetraethyl orthosilicate (TEOS). The effects of the type of surfactant and the concentrations of NaOH and AgNO3 on the size and morphology of the resulting Ag@SiO2 core–shell NPs were systematically investigated. The thickness of the silica shell could be finely tuned from 9.3 to 38.9 nm by easily adjusting the amount of TEOS. The crystal violet molecule was used for examining SERS and SEF properties of Ag@SiO2 core–shell NPs with different SiO2 thicknesses. The current work will provide guidance for further understanding the growth mechanism of Ag@SiO2 core–shell NPs and how the thickness of silica shell affects the SERS-SEF properties. [ABSTRACT FROM AUTHOR]

The coal indirect liquefied diesel soot (Coal‐to‐liquids diesel soot, CS) was collected by a self‐made soot trapper. CS was modified with cetyltrimethyl ammonium bromide (CTAB) and named as CS‐CTAB. The tribological properties of CS and CS‐CTAB in 10#white oil(10#WO) were tested on a WTM‐2E controlled atmosphere miniature friction and wear testing machine. The morphology, composition, and tribological mechanism of CS and modified CS‐CTAB were studied by using TEM, XPS, XRD, Raman, and other instruments. The results showed that CS modified by CTAB is wrapped and entangled in long chains. Their main structure components are all amorphous carbon with a small amount of graphite crystallites. The addition of CS‐CTAB (0.8 wt%) significantly reduces both AFC and wear rate, with reductions of 32.9% for AFC, and 65.6% for wear rate compared to no additive. The anti‐friction and anti‐wear effect of CS is greatly improved after being modified by CTAB. Mechanism analysis shows that CS as a lubricant additive, acts as a micro‐bearing in the friction process and falls off under the action of shear force to generate an independent graphite sheet, thus forming a graphite protective film on the surface of 304 stainless steel plate. However, CS has the defects of low graphitization degree, large particle size, and easy agglomeration. During friction, uneven adsorption of CS on the surface can worsen wear. However, CTAB modification can improve dispersion stability in 10#WO and effectively reduce wear on the friction surface. [ABSTRACT FROM AUTHOR]

A highly efficient, novel, two‐phase liquid method using phase transfer catalyst is reported to prepare β‐lactam‐conjugated silver nanoparticles as an approach to improve antibacterial activity of β‐lactams. In the method assisted by cetyltrimethylammonium bromide, NaBH4 reduced AgNO3 producing silver NPs that are coated with β‐lactams. The studies conducted provide a generalized method applicable to all types of β‐lactam substrates for capping on silver NPs. The NPs have been characterized by UV–Visible, Fourier transform infrared spectroscopy, x‐ray diffraction, transmission electron microscopy, and dynamic light scattering methods. [ABSTRACT FROM AUTHOR]

A relatively new member of the group of electrochemically induced deposition is that of templated sol-gel deposition. Uniform and smooth mesoporous silica thin films were first fabricated by an ECiD process nicknamed electrochemically assisted self-assembly or EASA, introduced by Walcarius et al. The addition of cetyltrimethylammonium bromide or CTAB as organic template molecules to the tetraethyl orthosilicate (TEOS) sol-gel precursor solution resulted in silica thin films with highly ordered, hexagonal arrays of vertical mesopores of 2–3 nm in diameter. These films have been proposed for applications in electroanalysis and sensors where effects such as pre-concentration or perm selectivity have been exploited. Their synthesis combines the well-established field of templated sol-gel synthesis with an electrochemically induced deposition process. To prevent spontaneous gel formation, the silica sol-gel precursor solution has a mildly acidic pH which kinetically inhibits the gelation reaction. Only when a cathodic potential/current is applied to electrogenerate OH- ions from the pro-base (water mostly), the gelation reaction is catalyzed by the local increase in pH, resulting in the growth of silica gel films on the electrode. We will first review the principles of sol-gel reactions, before proceeding to details of ECiD of sol-gel films. [ABSTRACT FROM AUTHOR]

Measuring pH in oxidizing solutions is a crucial issue in areas such as aquaculture, water treatment, industrial chemistry, and environmental analysis. For this purpose, a low-cost potentiometric flexible sensor using a polymer film as a pH-sensitive material has been developed in this study. The sensor consists in a polyaniline film electrodeposited from a sulfuric acid solution on a gold electrode previously deposited on a flexible polyimide substrate. The resulting polyaniline-based pH sensors showed an interesting performance detection in aqueous solution, leading to sensitive (73.4 mV per unit pH) and reproducible (standard deviation of 1.75) responses over the entire pH range from 3 to 8. On the contrary, they were inoperative in the presence of oxidizing hypochlorite ions. Thus, other polyaniline films were electrodeposited in the presence of cetyltrimethylammonium bromide or Tritonx100 surfactant in an attempt to improve the sensing performance of the pH sensors in oxidizing solutions. The pH sensors based on polyaniline and Tritonx100 surfactant were then found to be sensitive (62.3 mV per unit pH) and reproducible (standard deviation of 1.52) in aqueous solutions containing hypochlorite ions. All polyaniline films were also characterized by profilometry and electronic microscopy to correlate the physicochemical features with the performance of the sensors. [ABSTRACT FROM AUTHOR]

The aim of this research was to assess the efficacy of different microbial strains in the decolorization of anthraquinone dyes. Strain R81 was obtained from a textile company's wastewater discharge for its remarkable ability to decolorize reactive blue 19 (RB19). By employing physiological and biochemical analyses, along with 16S rRNA gene sequencing, strain R81 was determined to be Brevibacillus laterosporus. After optimization, the decolorization rate achieved a peak of 86.24% over a 48‐h timeframe, utilizing an initial dye concentration of 100 mg L–1. The decolorization capacity of strain R81 was observed to be impeded by heightened levels of salt and temperature in culture solutions, yet remained unaltered when R81 cells were directly introduced into dye solutions. Furthermore, cells that were induced through prior cultivation in a medium containing RB19 demonstrated enhanced efficacy in decolorization compared to noninduced cells. Subsequent analysis indicated that the development of biofilms and the synthesis of polysaccharides by strain R81 were augmented in a concentration‐dependent fashion by RB19. Nevertheless, the decolorization efficacy of R81 was impeded by the existence of sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB), both of which possess the capacity to eliminate polysaccharides. The decolorization capabilities were reinstated by the SDS or CTAB eluent containing polysaccharides, suggesting a reliance on the presence of polysaccharides. The employment of stepwise diethylaminoethyl (DEAE)‐cellulose chromatography and decolorization experiments elucidated the importance of a specific polysaccharide in the decolorization process. This study proposes a bacteria‐derived polysaccharide as a promising remedy for treating dyeing wastewater contaminated with anthraquinones. [ABSTRACT FROM AUTHOR]

In this work, tungsten oxide (WO3) thin films are grown on FTO glass using a facile spin coating method and an ink composed of WO3 nanoparticles synthesized under varying concentrations of cetyltrimethylammonium bromide (CTAB) surfactant. The influence of variation of the CTAB concentration on the quality and electrochemical performance of the prepared WO3 thin films is investigated. Cyclic voltammetry and electrochemical impedance spectroscopic analysis confirm that the thin film prepared with a CTAB/Na2WO4·2H2O molar ratio of 2.451 exhibits significantly enhanced electrochemical performance, demonstrating fast reaction kinetics for Li+ ions (diffusion coefficient = 1.08 × 10−9 cm2 s−1) compared to the pristine WO3 thin film (diffusion coefficient = 1.42 × 10−10 cm2 s−1) lacking any CTAB addition. These improved electrochemical characteristics of modified WO3 thin films are attributed to the increased porosity and a higher electroactive surface area. [ABSTRACT FROM AUTHOR]

The aim of this work was application of the hydroxyapatite (HAP) in various amounts by weight as a filler of natural rubber (NR) biocomposites. Innovatively, silanes, that is, (3‐aminopropyl)‐triethoxysilane (APTES) and bis[3‐(triethoxysilyl)propyl] tetrasulfide (TESPTS), surfactant, that is, cetyltrimethylammonium bromide (CTAB), and alkylimidazolium ionic liquids (ILs) with halide anions, that is, 1‐butyl‐3‐methylimidazolium chloride (BmiCl) and 1‐decyl‐3‐methylimidazolium bromide (DmiBr), were used to improve the dispersion of the HAP and curatives particles in the rubber matrix, and consequently the curing characteristics and properties of NR biocomposites. The influence of HAP and dispersants on the crosslink density, tensile properties, thermal stability, resistance to thermo‐oxidative aging, and ability to damp vibration of vulcanizates were investigated. It has been proven, that HAP can be efficiently used as a filler of NR biocomposites alternatively to commercial inactive or active fillers, for example, chalk, talc, or silica. The optimal HAP content is 30 phr. HAP did not detrimentally affect the curing characteristics of NR composites, crosslink density, and damping properties of the vulcanizates, while significantly raised their tensile strength, thermal stability, and resistance to thermo‐oxidative aging. Most importantly, CTAB and ILs considerably improved the dispersion of HAP and curatives particles in the NR matrix and consequently lowered the vulcanization temperature by approximately 25°C and enhanced by approximately 50% the crosslink density and tensile strength of the NR biocomposites. [ABSTRACT FROM AUTHOR]

A series of MOF-derived ZrO2-supported Pd-Ni bimetallic catalysts (PdNi/UiO-67-CTAB(n)-A500) were prepared by co-impregnation and pyrolysis at 500 °C under air atmosphere using UiO-67-CTAB(n) (CTAB: cetyltrimethylammonium bromide; n: the concentration of CTAB; n = 0, 3, 8, 13, 18) as a sacrificial template. The catalytic activity of PdNi/UiO-66-CTAB(n)-A500 in 1,3-butadiene hydrogenation was found to be dependent on the crystal morphology of the UiO-67 template. The highest activity was observed over the PdNi/UiO-67-CTAB(3)-A500 catalyst which was synthesized using UiO-67-CTAB(3) with uniform octahedral morphology as the template for the 1,3-butadiene selective hydrogenation. The 1,3-butadiene conversion and total butene selectivity were 98.4% and 44.8% at 40 °C within 1 h for the PdNi/UiO-67-CTAB(3)-A500 catalyst, respectively. The catalyst of PdNi/UiO-67-CTAB(3)-A500 can be regenerated in flowing N2 at 200 °C. Carbon deposited on the surface of the catalyst was the main reason for its deactivation. This work is valuable for the high-efficiency bimetallic catalyst's development on the selective hydrogenation of 1,3-butadiene. [ABSTRACT FROM AUTHOR]

This research paper focuses on the removal of the nonsteroidal anti-inflammatory drug, ibuprofen, from an aqueous solution using a dissolved air flotation process. The comparison of different types of cationic surface-active agents such as cetyltrimethyl ammonium bromide (CTAB), tetrabutyl ammonium bromide (TBAB), and octyltrimethyl ammonium bromide (OTAB) have been employed to scrutinize the effective removal of the ecotoxic pharmaceutically active compound. The work included the influencing parameters such as pressure, contact time, surfactant dosage, pH, flow rate, and initial concentration owing to the best-optimized conditions. The maximum removal rate of 96.09% was achieved at 15 min for CTAB, TBAB had 62.36% at 45 min, and 89.6% was obtained for OTAB at 30 min, with 50 mg L−1 as the initial concentration and pH = 4. The removal rate was better with the optimized dosage of CTAB at 0.6 g, TBAB at 1.2 g, and OTAB at 1.0 g. It was observed that the geometric shape of the surface-active agents had greater impacts on the contaminants' efficiency. CTAB and OTAB were combined to find out the best possible removal rate of contaminants. The synergistic effect augments surfactant-based occurrence to be better in forming a good foaming effect and tends to have a lower critical micelle concentration (CMC). From the evaluation of kinetic models, pseudo-second-order flotation kinetics fitted the experimental data best. Furthermore, the formed metabolites that had been identified using gas chromatography-mass spectrometry were found to be less toxic than the parenting compounds. [ABSTRACT FROM AUTHOR]

Attapulgite (APT) is widely used in wastewater treatment due to its exceptional adsorption and colloidal properties, as well as its cost-effectiveness and eco-friendliness. However, low-grade APT generally limits its performance. Here, a colloid mill-assisted ultrasonic-fractional centrifugal purification method was developed to refine low-grade APT. This process successfully separated and removed impurity minerals such as quartz and dolomite from the raw ore, resulting in a refined APT purity increase from 16.9% to 60% with a specific surface area of 135.5 m2∙g−1. Further modifying of the refined APT was carried out through the hydrothermal method using varying dosages of cetyltrimethylammonium chloride (CTAC), resulting in the production of four different APT adsorbents denoted as QAPT-n (n = CTAC mole number) ranging from 0.5 to 5 mmol. Using Congo red (CR) as the target pollutant, the QAPT-5 sample exhibited the best adsorption capacity with the maximum quantity of 1652.2 mg∙g−1 in a neutral solution at 30 °C due to the highest surface charge (zeta potential = 8.25 mV). Moreover, the QAPT-5 pellets (~2.0 g adsorbent) shaped by the alginate-assisted molding method removed more than 96% of 200 mL aqueous solution containing 200 mg∙L−1 CR and maintained this efficiency in 10 adsorption–elution cycles, which exhibited the promising practical application. [ABSTRACT FROM AUTHOR]

In this work, we studied the effect of additions of decahydronaphthalene (decalin) and its derivative, perfluorodecalin (octadecafluorodecalin) on the lithium metal deposition and dissolution, in particular, the dendrite formation, at the anodes of lithium secondary power sources in an electrolyte based on lithium hexafluorophosphate in the mixture of ethylene carbonate and diethyl carbonate. The study was carried out using the methods of current transients and electrochemical impedance. The results showed that, in contrast to traditional cationic surfactants cetyltrimethylammonium bromide and hexadecylpyridinium bromide, which we have studied earlier, the decalin and perfluorodecalin demonstrated specific interaction with the surface of the lithium electrode. Moreover, the interaction with decalin is so strong that it actually blocks the processes of both lithium deposition and anodic dissolution at the surface of the lithium electrode. The interaction of perfluorodecalin with the lithium surface turned out to be weaker. As a result, perfluorodecalin does not interfere with the cycling of the lithium-metal anode, but at the same time shows an inhibitory effect on the dendrite formation. In the electrolyte added with perfluorodecalin, the lithium anode was able to undergo more than 80 charging–discharging cycles with a Coulomb efficiency of 70–80%, while without the additive, the number of cycles was less than 40, and the Coulomb efficiency was 60% or lower. [ABSTRACT FROM AUTHOR]

The goal of this work is to confirm our earlier conclusion that the regularities observed during the electrodeposition of metallic lithium on copper and lithium electrodes can be associated with differences in the properties of the so-called solid electrolyte interphase formed at these electrodes in contact with the electrolyte. To do this, we analyzed the electrochemical impedance spectra measured during the above processes by using the method of the distribution of relaxation times. The electrolyte addition with surfactants (the cetyltrimethylammonium bromide and hexadecylpyridinium bromide) was shown to lead to a significant change in the properties of the solid electrolyte interphase layers and a noticeable increase in the values of the impedance components associated with the Faradaic processes at these electrodes. This indicates an inhibition of the lithium electrodeposition processes and the related process of dendrite formation under these conditions. At the same time, no such impedance components were observed at the fresh-formed deposit, which confirms our earlier conclusion that the effects of surfactants on the dendrite formation are associated with the changes in the properties of the solid electrolyte interphase layers in the presence of the surfactants, rather than the surfactants' adsorption at lithium and blocking of the dendrite growth. [ABSTRACT FROM AUTHOR]