Diester Research Articles

Self-dispersed molybdenum disulfide quantum dot/graphene crumpled ball as efficient high temperature lubricant additive

Inorganic nanoparticles have been proved as powerful lubricant additives at elevated temperature. However, the tribological properties are inevitably impaired due to poor dispersion and insufficient high temperature resistance of organic matter modified nanoparticles. Here, we prepare a self-dispersed molybdenum disulfide quantum dot/graphene crumpled ball (MGCB) comprising molybdenum disulfide quantum dot uniformly interspersed on the wrinkled graphene ball. The crumpled ball composite possesses excellent dispersity in polyalkylene glycol base oil without depending on surface modifiers. Compared with the conventional phosphate esters lubricant, our results indicate MGCB could vastly improve the lubrication performance of polyalkylene glycol with an extremely low concentration (0.05 wt%) at elevated temperature (150 °C), showing a friction reduction of 47% and a wear reduction of 30% compared with the conventional phosphate esters lubricant (tricresyl phosphate, TCP). This is because crumpled ball potentiates synergistic lubrication effect within the boundary lubrication. Overall, we envision our designed self-dispersed MGCB has significant potential in tribological application at elevated temperature.

Review of Electrolyte Additives for Secondary Sodium Batteries

AbstractAs the energy storage sector gains prominence, sodium batteries have garnered attention due to their affordability and the abundance of raw materials. Among the methods aimed at enhancing sodium battery performance, electrolyte additives are notably cost‐effective. Despite typically comprising no more than 5% of the components, these additives play a crucial role in improving battery cycle life and overall functionality. This review begins by analyzing the factors propelling the development of sodium batteries and the diverse roles of additives, extensively examines the roles of common functional groups (fluorine(F)‐containing, sulfonyl, sulfoxide, phosphate ester, nitrogenous, boron, silyl groups, etc.) in additives. Furthermore, it categorizes the latest functional electrolyte additives into five distinct types. Lastly, the review provides an overview of the potential for designing additives that are both sustainable and efficient. This comprehensive review aims to be a valuable resource for informing the strategic selection and enhancement of electrolyte additives, thereby facilitating future progress in the field.

Construction of durable flame retardant, anti-dripping, and smoke-suppressing recycled polyester fabric

Recycled poly(ethylene terephthalate) (R-PET) fabrics offer a sustainable and eco-friendly alternative to virgin PET but exhibit high flammability and increased smoke emission. In this study, magnesium hydroxide nanoparticles (nano-Mg(OH)2) with the particle size of 53 nm were synthesized and combined with cyclic phosphate ester through high-temperature and high-pressure immersion technology. The organic‒inorganic flame retardant (FR) agents were expected to penetrate the R-PET fibers, thus achieving high washing durability for flame retardancy and smoke suppression. The surface structural performance of nano-Mg(OH)2 and the smoke and heat suppression capacity, FR performance, mechanism and laundering resistance of the modified R-PET samples were also explored. The organic‒inorganic FR system significantly improved the FR properties and anti-dripping ability of R-PET while significantly reducing smoke and heat generation. Moreover, the modified R-PET fabrics exhibited self-extinguishing ability even after 40 washes, indicating their high washing resistance. The organic‒inorganic FR system was effective in both gas and condensed phase, providing multilevel fire safety. This study provides efficient and durable FR-functionalized R-PET fabrics with low smoke suppression and high fire safety.

Environmentally Relevant Concentrations of Triphenyl Phosphate (TPhP) Impact Development in Zebrafish.

A common flame-retardant and plasticizer, triphenyl phosphate (TPhP) is an aryl phosphate ester found in many aquatic environments at nM concentrations. Yet, most studies interrogating its toxicity have used µM concentrations. In this study, we used the model organism zebrafish (Danio rerio) to uncover the developmental impact of nM exposures to TPhP at the phenotypic and molecular levels. At concentrations of 1.5-15 nM (0.5 µg/L-5 µg/L), chronically dosed 5dpf larvae were shorter in length and had pericardial edema phenotypes that had been previously reported for exposures in the µM range. Cardiotoxicity was observed but did not present as cardiac looping defects as previously reported for µM concentrations. The RXR pathway does not seem to be involved at nM concentrations, but the tbx5a transcription factor cascade including natriuretic peptides (nppa and nppb) and bone morphogenetic protein 4 (bmp4) were dysregulated and could be contributing to the cardiac phenotypes. We also demonstrate that TPhP is a weak pro-oxidant, as it increases the oxidative stress response within hours of exposure. Overall, our data indicate that TPhP can affect animal development at environmentally relevant concentrations and its mode of action involves multiple pathways.

Phosphate Esters: New Coating Materials for a Sustainable Release Paper.

AbstractPaper manufacturers have long used silicone as the coating agent for release liners. However, silicone‐based release paper is very difficult to recycle due to covalent bonds between silicone and fibers. The most suitable solution to overcome this problem is to use alternative coating materials with adequate release properties, provided that they can be easily repulped in typical paper recycling facilities. We proposed a coating agent composed of phosphate esters and dimethylacetamide in order to manufacture a recyclable and efficient release paper. Analyses carried out on coated sheets showed that phosphate esters allowed the formation of a surface with adequate release properties (low peeling force and surface free energy). In addition, the residual adhesion values obtained with phosphate esters confirmed that they are well anchored on the backing paper surface, thus limiting the mass transfer to the adhesive tape.

A Hybrid-Salt Strategy for Modulating the Li+ Solvation Sheathes and Constructing Robust SEI in Non-Flammable Electrolyte Lithium Metal Batteries.

The electrode interface determines the performance of an electrochemical energy storage system. Using traditional electrolyte organic additives and high-concentration electrolyte emerging recently are two generally strategies for improving the electrode interface. Here, a hybrid-salt electrolyte strategy is proposed for constructing the stable electrode interface. Through the solubilization effect of phosphate ester on LiNO3, a hybrid-salts-based non-flammable phosphate ester electrolyte system (HSPE) with LiPF6 and LiNO3 as Li salts has been developed. By the strong interaction between NO3 - and Li+, the Li+ solvation sheath and solvent behaviors have been modulated, thus the undesirable effects of phosphate ester are eliminated and a robust SEI is formed. Experimental results and theoretical calculations illustrate that NO3 - as a kind of strongly coordinating anion can reduce the number of TEP molecules and lower the reduction reactivity of TEP. The reconfigured Li+ solvation structure allows the formation of an inorganic-rich SEI on the electrode surface. As a result, in the designed HSPE, the average coulombic efficiency of lithium plating/stripping is increased to 99.12 %. This work explored a new approach to construct the electrode interface and addressing the poor interface performance issue of phosphate esters.

Anomalous hydraulic fluid absorption by carbon fiber/PEKK composites: Physical and mechanical aspects

AbstractCarbon fiber (CF)/polyetherketoneketone (PEKK) composites are exposed to Skydrol, a hydraulic fluid made of phosphate esters widely used in the aviation field. The present study investigates Skydrol absorption of CF/PEKK composite layups and the associated PEKK matrix. A significant unexpected increase of Skydrol uptake is observed for cross‐ply composites (0.50%) compared to unidirectional ones (0.06%), independently of ply number. The use of ‘model’ fluids like water and ethanol allows to identify the origin of this anomalous Skydrol absorption in the case of cross‐ply layup. We propose that the latter involves an imbibition process governed by the fluid surface tension and the presence of submicronic cavities. SEM imaging of composite cross‐section after ion beam polishing confirms fiber‐matrix submicronic debonding in the interlaminar region in the cross‐ply composite. SEM–EDX confirms the presence of Skydrol into the submicronic cavities. Despite this anomalous absorption, off‐axis tensile testing as well as ILSS testing show no significant impact of Skydrol on CF/PEKK mechanical properties with less than 10% difference compared to the initial values.Highlights Absorption by diffusion of Skydrol in neat PEKK and CF/PEKK composites Link between fluid surface tension and anomalous Skydrol absorption Evidence of submicronic cavities in CF/PEKK composites by means of SEM–EDX Low impact of Skydrol on CF/PEKK mechanical properties

Cori Ester as the Ligand for Monovalent Cations.

Gerty T. and Carl F. Cori discovered, during research on the metabolism of sugars in organisms, the important role of the phosphate ester of a simple sugar. Glucose molecules are released from glycogen-the glucose stored in the liver-in the presence of phosphates and enter the blood as α-D-glucose-1-phosphate (Glc-1PH2). Currently, the crystal structure of three phosphates, Glc-1PNa2·3.5·H2O, Glc-1PK2·2H2O, and Glc-1PHK, is known. Research has shown that reactions of Glc-1PH2 with carbonates produce new complexes with ammonium ions [Glc-1P(NH4)2·3H2O] and mixed complexes: potassium-sodium and ammonium-sodium [Glc-1P(X)1.5Na0.5·4H2O; X = K or NH4]. The crystallization of dicationic complexes has been carried out in aqueous systems containing equimolar amounts of cations (1:1; X-Na). It was found that the first fractions of crystalline complexes always had cations in the ratio 3/2:1/2. The second batch of crystals obtained from the remaining mother liquid consisted either of the previously studied Na+, K+ or NH4+ complexes, or it was a new sodium hydrate-Glc-1PNa2·5·H2O. The isolated ammonium-potassium complex shows an isomorphic cation substitution and a completely unique composition: Glc-1PH(NH4)xK1-x (x = 0.67). The Glc-1P2- ligand has chelating fragments and/or bridging atoms, and complexes containing one type of cation show different modes of coordinating oxygen atoms with cations. However, in the case of the potassium-sodium and ammonium-sodium structures, high structural similarities are observed. The 1D and 2D NMR spectra showed that the conformation of Glc-1P2- is rigid in solution as in the solid state, where only rotations of the phosphate group around the C-O-P bonds are observed.

In silico phylogenetic, physicochemical, and structural characteristics of phytase enzyme from ten Aspergillus species

Phytic acid is a chemical compound consisting of inositol and phosphoric acid and is an antinutrient compound found in monogastric poultry feed ingredients made from cereal crops. Phytase hydrolyzes phosphoester bonds in phytic acid, releasing inorganic phosphate and phosphate esters. Aspergillus is a genus of molds that produce phytase and has been widely used in phytase production because they are easy to culture. This study aims to compare the structures, physicochemical characteristics, and phylogenetic relationships of phytases from several species of Aspergillus in silico as an initial screening step in obtaining the most suitable phytase to be used in poultry feed. Phylogenetic trees were constructed using MEGA 11 and physicochemical characteristics were analyzed using ProtParam. Protein structures were modeled with AlphaFold. The phytase structures were then docked with phytic acid using the YASARA Structure. The results showed that phytase 1QFX from Aspergillus niger, P34755 from A. awamori, and D5HQ11 from A. ficuum have very high similarity in terms of phylogenetics, sequences, physicochemical characteristics, and protein structures. The docking results from the three phytase structures showed that phytase 1QFX has the most negative ΔG value and the lowest Kd, which indicated the highest affinity to the phytic acid substrate. This research concludes that among the three phytase structures that have been compared and docked with phytic acid, phytase 1QFX from A. niger is the most suitable to be applied to poultry feed.

Fabrication of phosphorylated UiO-66 for efficient selective removal of Pb2+ from acidic wastewater

Metal-organic framework (MOF) materials have emerged as promising candidates for treating heavy metal wastewater because of their controllable pore size, high specific surface area, and abundant active sites. Nevertheless, the currently reported MOFs usually require near-neutral environments (pH = 5–6) to achieve efficient removal of Pb2+ and cannot be applied to acidic environments (pH = 2–3). In this work, the structurally stabilized zirconium-based MOF UiO-66 was chosen as the object of study. Three phosphate ester-based MOFs (UiO-66-(OPO3)X) containing different amounts and spatial positions were designed and prepared by simple chemical modification and used to remove Pb2+. Adsorption experiments showed that they could reach adsorption equilibrium in 30 min with excellent adsorption rate. Owing to the unique ionization ability of the phosphate ester group, UiO-66-(OPO3)X maintains a high removal efficiency of Pb2+ even at pH = 2 and pH = 3. In addition, selectivity and competition experiments demonstrated that UiO-66-(OPO3)X possessed excellent selectivity and anticompetitive ability towards Pb2+.The excellent regeneration performance demonstrates their value for practical application. Moreover, the adsorption mechanism was investigated in detail by experiment combined with density functional theory (DFT).

Syntheses and Spectroscopic Characterization of Selected Methyl Quinolinylphosphonic and Quinolinylphosphinic Acids; Rationalized based on DFT Calculation

Abstract: The quinoline derivatives arouse interest due to their broad spectrum of activity. The phosphorus compounds under investigation, quinolinylphosphonic and -phosphinic acids and aminophenylphosphonic and -phosphinic acids, possess potent bioactive properties, mimicking amino acids, phosphate esters, anhydrides, or carboxylate groups in enzymes. Despite its potential value, there is no reported example of quinolinylphosphonic or - phosphinic acids with phosphonic or phosphinic functional groups connected directly to the benzene ring in quinoline constitution. The selected quinoline derivatives have been synthesized by adopting the Skraup-Doebner-Von Miller reaction. To this end, the syntheses of aminophenylphosphonic and -phosphinic acids were conducted and afforded the target products with high yield. All structures have been proven by the combination of NMR, IR, MS, and HRMS techniques and were rationalized based on DFT calculation. The structures of triphenylphosphane oxide (TPO), diphenylphosphosphinic acid (1c), (tert-butyl)phenylphosphinic acid (1d) and bis(3-nitrophenyl)phosphinic acid (2c) were determined by single-crystal X-ray diffraction measurements. The Hirshfeld surface analyses for 1c, 1d and 2c were performed to analyze the intermolecular interactions in their crystal structures. According to our findings, the presence of numerous intermolecular PO•••H, NO•••H, and CH•••O contacts stabilizes the crystal structures. The NO•••H interactions manifest in the IR spectrum of 2c crystal as a narrow band with a maximum at 3088 cm-1. The PO•••H intermolecular interactions are attributed to a weak experimental band at 1288 cm-1.

Construction of organophosphate-functionalized α‑zirconium phosphate towards fire-resistant, weather-resistant and antibacterial reinforcement of transparent fireproof coatings applied on wood substrates

To meet the requirements of fire protection and decorative properties of wood, developing transparent fireproof coatings with excellent comprehensive performance is vital. A new category of organophosphate-grafted α‑zirconium phosphate (α-ZrP) was synthesized as functional flame retardant, then in combination with melamine-formaldehyde resin prepared comprehensive transparent fireproof coatings covering fire protection, smoke suppression, anti-bacteria and weatherability. The results show that adding α-ZrP results in an effective improvement of the mechanical properties, fire protection and smoke suppression under the premise of guaranteeing the high transparency of the coatings. In particular, the MZrPPB3 sample containing a 98:2 mass ratio of phosphate ester to modified α-ZrP possesses 55.2 %, 76.2 % and 23.7 % decrement in flame spread rating, smoke density rating and equilibrium backside temperature at 900 s in comparison with MZrPPB0 sample without α-ZrP, respectively, accompanied by superior adhesion classification of 4B rating and pencil hardness of 2H rating. The efficient fire protection performance of α-ZrP-containing coatings attributes success to the high-quality intumescent char formed by the stable crosslinking and aromatic structures, as confirmed by characterization of FTIR and SEM-EDS analyses. Additionally, adding α-ZrP into the coatings confers them extraordinary weatherability rich in appearance integrity and fire protection performance after accelerated aging test. Meantime, the obtained satisfactory antibacterial property of coatings relates to the presence of α-ZrP with an antibacterial rate of up to 99.0 % for MZrPPB3 against Escherichia coli.

Innovative phosphorus-containing epoxy resins: A new approach to acidic corrosion protection

The main challenges in the corrosion field for steel include its high susceptibility to acidic degradation and the need for sustainable and efficient corrosion inhibitors. The main objective was to synthesize a novel phosphorus-containing trifunctional epoxy resin, named phosphoric ester triglycidyl ether hydroquinone (TGEHEP), through a two-step process. Initially, the intermediate known as phosphoric ester trihydroquinone was synthesized. Subsequently, epichlorohydrin was added in the second step to produce the new TGEHEP epoxy resin. For the structural characterization of this compound, FTIR, 1H and 13C NMR were used. These techniques confirmed the final chemical structure of the synthesized macromolecule. The newly developed TGEHEP epoxy resin was subsequently utilized as a protective agent for carbon steel in 1.0 M HCl. This study incorporated various techniques, including PDP, EIS, EFM, DFT, MC, and MD simulations. Additionally, SEM/EDS was applied to examine the surface. These methods allowed us to analyse the surface structure and chemical composition of the sample, providing further insights into the adsorption process and corrosion protection mechanism. Electrochemical test results revealed that the TGEHEP concentration significantly enhanced protection. Notably, EIS demonstrated an outstanding protection efficiency of 96.70% with 10−3 M TGEHEP epoxy resin. The polarization findings also indicate that the resin acts as a mixed inhibitor. In line with the Langmuir isotherm, epoxy resin was effectively used to protect the metal surface. Furthermore, thermodynamic kinetic parameters were estimated to evaluate the adsorption of the inhibitor. TGEHEP showed a greater adsorption energy (-195.05 kcal/mol) than did its protonated form (-178.65 kcal/mol), indicating that the interaction with the iron surface was stronger in its neutral form. A significant increase in the concentration of TGEHEP was detected, reaching a maximum of 762.4 Ω.cm² at a concentration of 10−3 M. This suggests that TGEHEP forms a barrier that impedes electron transfer, a key factor in corrosion processes. The ΔGads is −44.3 kJ/mol, which is within the typical range for chemisorption. This suggests that the adsorption of TGEHEP onto the metal surface includes more than just physical adsorption; it likely involves electron transfer, which is characteristic of a chemisorptive bond. Comparatively, TGEHEP demonstrates superior performance to previously published corrosion inhibitors, with its efficacy not only attributed to its unique chemical structure but also to its environmentally benign nature.

Fabrication of flame retardant poly(methyl methacrylate) with excellent comprehensive properties based on a new phosphorus-silicon-nitrogen-synergistic system

In general, the addition of phosphate ester flame retardants can improve the flame retardancy of polymethyl methacrylate (PMMA), but the flame retardant efficiency is low when phosphate ester is used alone and the tensile strength and hardness of the material are reduced. It is a challenge to improve the flame retardancy of PMMA while maintaining its inherent mechanical properties. In this study, a polyphosphate-coated silica (SZP) was prepared, which was compounded with dimethyl methylphosphonate (DMMP). At the same time, methacrylamide (MAM), which can be copolymerized with PMMA, was introduced to construct a synergistic phosphorus-nitrogen-silicon flame retardant system. The three components can work together in the gas phase and condensed phase. The results showed that when 12.5% DMMP, 5% MAM and 2.5% SZP were added, the composite material had the best comprehensive performance, its limiting oxygen index (LOI) reached 25.1%, and its total heat release was only 70% of the pure sample. More importantly, the addition of DMMP would significantly reduce the mechanical properties of PMMA. The introduction of SZP and MAM alleviated this problem. Compared with the pure sample, the mechanical properties of PMMA7 did not decrease but increased slightly. The flame retardant mechanism was also analyzed. This study provides a new idea for the industrialization of flame retardant PMMA.

First Insight into Fetal Exposure to Legacy and Emerging Plasticizers Revealed by Infant Hair and Meconium: Occurrence, Biotransformation, and Accumulation.

Epidemiological studies have demonstrated the embryonic and developmental toxicity of plasticizers. Thus, understanding the in utero biotransformation and accumulation of plasticizers is essential to assessing their fate and potential toxicity in early life. In the present study, 311 infant hair samples and 271 paired meconium samples were collected at birth in Guangzhou, China, to characterize fetal exposure to legacy and emerging plasticizers and their metabolites. Results showed that most of the target plasticizers were detected in infant hair, with medians of 9.30, 27.6, and 0.145 ng/g for phthalate esters (PAEs), organic phosphate ester (OPEs), and alternative plasticizers (APs), and 1.44, 0.313, and 0.066 ng/g for the metabolites of PAEs, OPEs, and APs, respectively. Positive correlations between plasticizers and their corresponding primary metabolites, as well as correlations among the oxidative metabolites of bis(2-ethylhexyl) phthalate (DEHP) and 1,2-cyclohexane dicarboxylic acid diisononyl ester (DINCH), were observed, indicating that infant hair retained the major phase-I metabolism of the target plasticizers. While no positive correlations were found in parent compounds or their primary metabolites between paired infant hair and meconium, significant positive correlations were observed among secondary oxidative metabolites of DEHP and DINCH in hair and meconium, suggesting that the primary metabolites in meconium come from hydrolysis of plasticizers in the fetus but most of the oxidative metabolites come from maternal-fetal transmission. The parent compound/metabolite ratios in infant hair showed a decreasing trend across pregnancy, suggesting in utero accumulation and deposition of plasticizers. To the best of our knowledge, this study is the first to report in utero exposure to both parent compounds and metabolites of plasticizers by using paired infant hair and meconium as noninvasive biomonitoring matrices and provides novel insights into the fetal biotransformation and accumulation of plasticizers across pregnancy.

Scalable phosphorylated cellulose production with improved environmental sustainability, crosslinkability and processability using 3D bioprinting for dye remediation

In the present work, phosphorylated cellulose (PC) gel has been produced following an environmentally benign approach using agro-based chemicals with improved yield. The PC gels produced were transparent, negatively charged with high consistency, charge content (1133.33 mmol/kg), degree of substitution (DS) of 0.183 and increased yield (>87 %). The XPS and EDS analysis confirms the covalently bonded phosphate groups at weight percent of 9.42 % and 11.01 %, respectively. The life cycle assessment (LCA) shows that PC gel production via the phosphorylation route is an ecologically favourable strategy compared with traditional TEMPO oxidation, resulting in 1.67 times lower CO2 emission. The rheological studies of PC gels show shear-thinning behaviour with improved 3D printability followed by heat-induced crosslinking of phosphate groups. The mechanistic insights for the condensation of phosphate to form a phosphoric ester group during cross-linking were evaluated through 31P solid-state NMR and XPS studies. Interestingly, the 3D-printed structures showed high structural stability under both compression and tensile load in both dry and wet conditions, with high water absorption (5408.33 %) and swelling capacity of 700 %. The structures show improved methylene blue (MB) remediation capabilities with a maximum removal efficiency of 99 % for 10–200 mg/L and more than seven times reusability. This work provides a green, facile and energy-efficient strategy for fabricating PCs with easy processability through additive manufacturing techniques for producing value-added products, opening up new avenues for high-performance applications.

Self‐emulsification synthesis of epoxy phosphate ester and its flame‐retardant mechanism in flexible poly(vinyl chloride)/magnesium hydroxide composites

AbstractA trade‐off dilemma exists for simultaneously improving the mechanical properties and flame resistance of flexible polyvinyl chloride (fPVC)/magnesium hydroxide (MH) composites. In this study, epoxy phosphate ester (EPE), a hydrophobic surface modifier of MH, was synthesized using a self‐emulsification method. After modification, EPE was bonded to the surface of MH (MHEPE) without altering its morphology. The results of limiting oxygen index and cone calorimetry tests indicated that fPVC/MHEPE exhibited better flame retardancy and smoke suppression effects than did fPVC/MH. The peak of the heat release rate, total heat release, peak of the smoke production rate, and total smoke production of the fPVC/MHEPE composite were 206.0 kJ m−2, 45.90 MJ m−2, 0.0729 m2 s−1, and 9.88 m2, which were 8.64%, 14.00%, 27.61%, and 9.02% lower than those of the fPVC/MH composite, respectively. For the fPVC/MHEPE composite, a compact and continuous char residue formed, which could inhibit heat and flammable volatile migration between the matrix and burning zones. In the gas phase, the dilution effect of H2O vapor reduced the concentrations of O2 and flammable volatiles. The free‐radical quenching effect of ·PO and ·PO2 also played a vital role in extinguishing flame and terminating combustion. Further, the introduction of EPE improved the tensile and impact strengths of the fPVC/MH composites because of the excellent interfacial compatibility between MHEPE and the fPVC matrix. This study provides a simple and workable solution for the trade‐off dilemma, and the remarkable flame retardancy and mechanical properties of the fPVC/MHEPE composite render it a promising cable material.

Experimental Study on Dispersion Stability and Polishing Performance of Polishing Solution Based on Micro-Abrasive Water Jet Polishing

In micro-abrasive water jet polishing (MAWJP) technology, where abrasive particles serve as polishing tools, particles tend to form large clusters, leading to increased nozzle wear and diminished material polishing quality. Achieving a polishing solution with good dispersion stability is crucial for enhancing polishing accuracy and minimizing nozzle wear. Therefore, this study employed three dispersants with distinct dispersion mechanisms to examine the impact of each dispersant’s concentration on the dispersion stability of the polishing solution across various abrasive concentrations. Through experimentation, the optimal dispersant type and concentration ratio of abrasive to dispersant were determined, and the effect of the selected dispersant on jet polishing performance was validated. The results of the dispersion stability experiment indicated that, in comparison to Na(PO3)6 and polyethylene glycol (PEG), the polishing solution containing 1.0–2.0 wt% phosphoric ester compounds exhibited a more stable dispersion effect (zeta potential < −50 mV) and superior dispersibility, characterized by a smaller average particle size. Furthermore, K9 optical glass was subjected to fixed-point and local polishing using phosphoric ester compounds as the dispersant. The fixed-point polishing experiment revealed that, at a dispersant concentration of 1.0 wt% and an abrasive concentration of 20 wt%, a smooth and symmetrical material removal profile could be achieved. In the local polishing experiment, the reduction rate of the root mean square of the surface roughness (RMS) increased from 54.33% to 82.24%, and the reduction rate of peak-to-valley height difference in surface (PV) increased from 38.84% to 68.97%. In conclusion, the incorporation of a dispersant proves effective in enhancing the dispersion stability of the polishing solution and dispersibility of the abrasive particles, thereby improving the surface quality of the materials in MAWJP.

Evaluation of organophosphorus pesticide tyrosine adducts for postmortem change by human serum albumin with liquid chromatography quadrupole Orbitrap mass spectrometry.

Organophosphorus pesticides (OPPs) having a phosphate ester moiety, such as malathion (MA) and methidathion (DMTP), are widely used and have been detected in many fatal cases of accidental exposure or suicide in Japan. In forensic toxicology, the accurate determination of blood OPP concentration is mandatory to prove death by OPP poisoning. However, fatal pesticide concentration in blood at autopsy varies depending on the circumstances surrounding the dead body. In this study, we found that 16 OPPs were degraded by human serum albumin (HSA) in a temperature-dependent fashion. The mechanism underlying MA, DMTP, azinphos-methyl, etrimfos, fenthion (MPP), pirimiphos-methyl, (E)-dimethylvinphos, (Z)-dimethylvinphos, vamidothion, edifenphos (EDDP), fosthiazate, and pyraclofos degradation involves the formation of adducts with tyrosine residues in HSA. The mass spectra obtained by liquid chromatography quadrupole Orbitrap mass spectrometry revealed that phosphate ester amino acid adducts such as Y-adduct1, Y-adduct2, Y-adduct3, Y-adduct4, and Y-adduct5 were formed in HSA solution incubated with OPPs. These results indicate that the 16 OPPs are postmortem changed by HSA. The detection of phosphate ester amino acid adducts such as Y-adduct1, Y-adduct2, Y-adduct3, Y-adduct4, and Y-adduct5, instead of MA, DMTP, azinphos-methyl, etrimfos, MPP, pirimiphos-methyl, (E)-dimethylvinphos, (Z)-dimethylvinphos, vamidothion, EDDP, fosthiazate, and pyraclofos per se, may be used to determine death by these OPPs poisoning.

Transport and health risk of legacy and emerging per-and polyfluoroalkyl substances in the water cycle in an urban area, China: Polyfluoroalkyl phosphate esters are of concern

Polyfluoroalkyl phosphate esters (PAPs) are a group of emerging alternatives to the legacy per- and polyfluoroalkyl substances (PFAS). To better understand the transport and risk of PAPs in the water cycle, 21 PFAS including 4 PAPs and 17 perfluoroalkyl acids were investigated in multiple waterbodies in an urban area, China. PFAS concentrations ranged from 85.8 to 206 ng/L, among which PAPs concentrations ranged from 35.0 to 71.8 ng/L, in river and lake water with major substances of perfluorooctanoic acid (PFOA), 6:2 fluorotelomer phosphate (6:2 monoPAP), and 8:2 fluorotelomer phosphate (8:2 monoPAP). As transport pathways, municipal wastewater and precipitation were investigated for PFAS mass loading estimation, and PAPs transported via precipitation more than municipal wastewater discharge. Concentrations of PFAS in tap water and raw source water were compared, and PAPs cannot be removed by drinking water treatment. In tap water, PFAS concentrations ranged from 132 to 271 ng/L and among them PAPs concentrations ranged from 41.6 to 61.9 ng/L. Human exposure and health risk to PFAS via drinking water were assessed, and relatively stronger health risks were induced from PFOS, PAPs, and PFOA. The environmental contamination and health risk of PAPs are of concern, and management implications regarding their sources, exposure, and hazards were raised.