Explore the vast range of titles available.

High flame-retardant efficiency and good hand feeling are particularly critical in the application of cotton fabrics. Herein, a reactive flame retardant (PAzP) with ammonium phosphate ester groups was designed and bonded to cotton fabric through a dip-pad-cure process. The obtained PAzP-treated fabrics exhibited good hand feeling and high fire safety. The finishing process had no essential effect on the crystal structure of cellulose. With 11.8 wt% PAzP bonded, the attributes of the fabric's texture, including resilience, softness, and smoothness, were nearly indistinguishable from those of pristine fabric. Meanwhile, PAzP-treated fabric achieved a LOI value of 33.3% and self-extinguished immediately after removing the igniter in the vertical burning test. The material exhibited outstanding performance in the cone calorimeter test, demonstrating a remarkable decrease in both heat and smoke release, thus indicating its exceptional fire safety properties. The investigation of char residue and decomposed volatiles confirmed that PAzP functioned as a flame retardant by generating graphitized char residues, which limit the propagation of heat and oxygen and curtailed the emission of flammable volatiles in the condensed phase. Additionally, PAzP released a substantial amount of CO2, which mitigated the flammable volatiles and oxygen in the gaseous phase. Overall, this study presents a potential strategy for producing cotton fabric that possesses excellent fire safety and comfortable tactile properties.

Two Ni(II) complexes [(Ni L1)(CH 3 COO) (H 2 O) 2 ](1) and [{(NiL2) (CH3COO)} 2 (µ-H 2 O)] (2) having different coordination environments around metal centres have been selected to investigate structure-activity correlation for DNA binding and homogenous phosphatase-like activities. Complex 1 is a monomer in which the octahedral Ni(II) center is coordinated to phenolate oxygen along with two nitrogen atoms from imine and amine groups of the deprotonated ligand HL1 . An oxygen atom of the acetate group is coordinated in monodentate mode, and two coordinated water molecules occupy the other two axial sites. Complex 2 is a dimer where each Ni(II) centre is coordinated in an octahedral environment through one imine nitrogen, one amine nitrogen, two bridging phenolate oxygens from two deprotonated ligands ( HL2) molecules, a mono-dentate acetate group, and a bridging water molecule. The role of structural features of both the complexes has been studied in DNA binding activity and phosphate ester bond cleavage of bis(4-nitrophenyl) phosphate (BNPP) as a model substrate. Complex 2 showed higher DNA binding ability than complex 1 due to its stable bridging structure and high nuclearity. The catalytic phosphate ester bond hydrolysis of BNPP was explored with both complexes spectrophotometrically. The dinuclear complex 2 also exhibited a higher rate of acceleration in the BNPP hydrolysis than mononuclear complex 1 . The active nucleophile from the coordinated water and cooperativity in two metal centres of complex 2 are the key features to cleave the phosphate ester bond of the substrate. Further, the first-order rate constants and various kinetic parameters based on the Michaelis-Menten equation were calculated for each complex. A significant phosphatase-like activity for complex 2 has been observed with a turnover number of 1.23 × 10 −2  s −1 . Graphical abstract A structure-activity relationship for phosphatase-like catalytic activities of two mono and di nuclear Ni(II) complexes has been studied. Dinuclear complex 2 exhibits higher phosphatase-like activity due to coordinated water molecules and cooperativity between two metal centres.

Steroid phosphate esters are very rare natural lipids that have been comparatively recently isolated from fractions of polar lipids of marine sponges and starfish. These steroids exhibit interesting biological activities. When using the PASS computer program, we showed that many of steroid phosphate esters showed antifungal, antihypercholesterolemic, anesthetic, and other activities with a confidence of 73 to 93%. In addition, some of them can be used as inhibitors of cholesterol synthesis and show hepatoprotection properties. Phosphonosteroids demonstrate antineoplastic and antihypercholesterolemic activities with a certainty of 85 to 90%. And also, they can be used as ovulation inhibitors or female steroid contraceptives with confidence from 86 to 98%.

A one-step procedure to obtain modified fibers containing n-decyl phosphate cellulose is proposed. The reaction was carried out at 150 °C in heterogeneous conditions with kraft pulp fibers in the presence of n-decyl monophosphate and N,N-dimethylacetamide (DMAc). The simultaneous addition of phosphorus and alkyl chain was characterized by solid-state nuclear magnetic resonance (13C and 31P-NMR), Fourier transform infrared spectroscopy and energy dispersive X-ray spectroscopy. The phosphorus content, estimated at 2.0%, was determined by UV-visible spectrophotometry. Results also indicated that grafted phosphate groups wear alkyl chains.

Polyfluoroalkyl phosphate mono-, di-, and tri-esters (mono-, di-, and triPAPs) are used to water- and grease-proof food packaging materials, and these chemicals are known precursors to perfluoroalkyl carboxylic acids (PFCAs). Existing analytical methods for PAPs lack sample clean-up steps in the sample preparation. In the present study, a method based on ultra performance liquid chromatography coupled to tandem mass spectrometry (UPLC/MS/MS) was developed and optimized for the analysis of mono-, di-, and triPAPs, including a clean-up step for the raw extracts. The method was applied to food samples and their PAP-containing packaging materials. The optimized UPLC/MS/MS method enabled the separation and identification of a total of 4 monoPAPs, 16 diPAPs, and 7 triPAPs in the technical mixture Zonyl®-RP. For sample clean-up, weak anion exchange solid phase extraction columns were tested. PAPs standard solutions spiked onto the columns were separated into a fraction containing neutral compounds (triPAPs) and a fraction with ionic compounds (mono- and diPAPs) with recoveries between 72–110 %. Method limits of quantification for food samples were in the sub to low picogram per gram range. For quantitative analysis of PAPs, compound-specific labeled internal standards showed to be essential as sorption and matrix effects were observed. Mono-, di-, and/or triPAPs were detected in all food packaging materials obtained from the Swedish market. Up to nine diPAPs were detected in the food samples, with the 6:2/6:2 and 6:2/8:2 diPAPs as the dominant compounds. DiPAP concentrations in the food samples ranged from 0.9 to 36 pg/g, which was comparable to individual PFCA concentrations in the same samples. Consumption of food packed in PAP-containing materials could be an indirect source of human exposure to PFCAs.

This study investigates the interfacial behavior of four phosphate ester ionic liquids (ILs) with contrasting cation hydrophobicity under humid environments. Through tribological tests, surface analysis, and molecular dynamics simulations, we reveal how moisture absorption governs lubricant film organization at metal interfaces. Aromatic ILs (imidazolium/pyridinium cations) exhibit significant degradation in lubrication after moisture exposure, with friction coefficients increasing by 0.03–0.05 and wear volumes scaling with humidity. This deterioration arises from competitive water–cation adsorption, where hydrogen bonding disrupts Fe-cation coordination bonds and destabilizes the protective film. In contrast, aliphatic ILs (tetraalkylammonium/phosphonium cations) maintain robust tribological performance. Their alkyl chains spatially confine water to outer adsorption layers (>17 Å from the surface), preserving a stable core lubricating film (~14 Å thick). Molecular dynamics simulations confirm that water co-adsorbs with aromatic cations (RDF peak: 2.5 Å), weakening interfacial interactions, while aliphatic ILs minimize cation–water affinity (RDF peak: 4 Å). These findings establish cation hydrophobicity as a critical design parameter for humidity-resistant lubricants, providing fundamental insights into water-mediated interfacial phenomena in complex fluid systems.

Bioresponsive ceramics, a new concept in ceramic biomaterials, respond to biological molecules or environments, as exemplified by salts composed of calcium ions and phosphate esters (SCPEs). SCPEs have been shown to form apatite in simulated body fluid (SBF) containing alkaline phosphatase (ALP). Thus, surface modification with SCPEs is expected to improve the apatite-forming ability of a material. In this study, we modified the surface of α-tricalcium phosphate (α-TCP) using methyl, butyl, or dodecyl phosphate to form SCPEs and investigated their apatite formation in SBF and SBF containing ALP. Although apatite did not form on the surface of the unmodified α-TCP in SBF, apatite formation was observed following surface modification with methyl or butyl phosphate. When ALP was present in SBF, apatite formation was especially remarkable on α-TCP modified with butyl phosphate. These SCPEs accelerated apatite formation by releasing calcium ions through dissolution and supplying inorganic phosphate ions, with the latter process only occurring in SBF containing ALP. Notably, no apatite formation occurred on α-TCP modified with dodecyl phosphate, likely because of the low solubility of the resulting calcium dodecyl phosphate/calcium phosphate composites. This new method of using SCPEs is anticipated to contribute to the development of novel ceramic biomaterials.

Plasma electrolytic oxidation (PEO) in an alkaline silicate electrolyte containing nanosized sepiolite fibers was carried out on magnesium alloy AZ31. The mineral fibers were loaded with different corrosion inhibitors and incorporated in situ during the PEO treatment. The composition and microstructure of the PEO coatings were investigated by SEM. It was shown that the fibers are located on the surface as well as inside the “weak spots” of the coating, i.e., pores and discharge channels. The fixation of the particles is caused by sintering due to the heat developed during the PEO treatment. Investigations using electrochemical impedance spectroscopy and linear sweep voltammetry in 0.01 M NaCl solution confirmed an improvement of the corrosion protection. The use of the inhibitors shifts the critical pitting potential in the anodic direction. Regarding efficiency, cerium-loaded sepiolite showed the best behavior by shifting the pitting potential by +0.9 V.

Mitigation of localized under deposit corrosion (UDC) in upstream oil and gas pipelines is an important research topic for both industry and academia. In a research program to better define the various inhibitor components that provide mitigation of UDC, this initial research investigates the effect of varied ratios of mono- to dinonylphenol phosphate esters (PE) by testing a set of specifically formulated inhibitors. Inhibitors with three mono- to di-PE ratios were tested in the presence and absence of 2-mercaptoethanol (ME). Using two 1.25 in (3.18 cm) diameter API 5L X65 pipeline steel samples and 250 μm silica sand, UDC testing was conducted for 28 d in a CO2 saturated solution at 70°C and 1 bar (100 kPa) total pressure. Analysis has shown that localized corrosion (pit penetration rate) increased for ME-free nonylphenol PE as the concentrations of di-PEs and mono-PEs approached equivalency. The nonylphenol PE inhibitor with a 50:50 mono- to di-PE ratio at 100 ppm concentration failed to protect the surface of the sample under the individual sand grains. Even the base product inhibitor package with no PE provided better mitigation under these test conditions than the 50:50 mono- to dinonylphenol PE. However, it was observed that the addition of ME provided a dramatic improvement in the mitigation of UDC for each mono- to di-PE ratio of the nonylphenol PE tested. From this research, it is seen that the mono- to di- PE ratio is important to consider when developing corrosion inhibitors containing PEs.

Combined effect of additives, over-based calcium sulfonate (OBCS) and phosphate ester were investigated on the decomposition of multi-alkylated cyclopentane (MAC). The decomposition processes of the lubricants on the nascent surface of bearing steel AISI52100 were investigated using a ball-on-disk friction tester in a vacuum chamber with a quadrupole mass spectrometer. According to our previous report, the decomposition reaction can be deactivated by the effect of lubricant additives such as organic sulfides and organic phosphates. In this report, the order of efficiency in decreasing the decomposition rate was: OBCS < phosphate ester < phosphate ester + OBCS. The mixed additive was more effective and stable for suppression of the tribochemical decomposition under severe contact conditions of high load and high sliding speed. The critical load for the decomposition which is the lowest load to detect the gas evolution due to the decomposition increased with the mixed additive. XPS and TOF–SIMS analysis revealed that additive molecules competitively chemisorbed on the steel surface and reaction occurred by the formation of calcium phosphate, which covered the steel surface and deactivated the catalytic activity of active sites leading to deactivation. As a result, decomposition of MAC decreased significantly by the combined effect of the additives.