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Cinnamides are common core structures that exist in a great number of pharmaceuticals and natural products. The development of efficient methods for preparing cinnamides is in great need. We report herein an efficient polyphosphoric acid (PPA)-promoted direct aldol condensation of an amide for the convenient and straightforward preparation of cinnamides. A variety of cinnamides were obtained in moderate-to-excellent yields (65–89%). This strategy features the use of equivalent amides and a short reaction time. [ABSTRACT FROM AUTHOR]

The impact of polyphosphoric acid (PPA) polymers and crumb rubber (CR) on bitumen's properties to enhance its performance was examined in this study. Laboratory samples were created with varying percentages of PPA (0.5% to 2%) and CR (6% to 18%) and subjected to extensive testing. Findings indicated that the combination of PPA and CR led to notable improvements in bitumen performance, including increased viscosity, softening point, elasticity, and recovery rates at elevated temperatures. Specifically, samples with 18% CR and 1.0% or 2.0% PPA demonstrated exceptional rheological properties and strength. The optimal combination (18% CR and 1.0% PPA) resulted in a uniform structure, while the maximum CR content did not compromise bitumen integrity. Both additives effectively minimized temperature sensitivity and aging, enhancing the bitumen's performance class significantly. [ABSTRACT FROM AUTHOR]

1,4,5,8‐Tetrafluoroacridine was successfully synthesized from 1,4,5,8‐tetrafluoroacridone through transfer hydrogenation using an in‐house ruthenium pincer catalyst followed by in situ dehydration. The synthetic protocol involves the copper‐catalyzed coupling of 2‐amino‐3,6‐difluorobenzoic acid 1 and 1,4‐difluoro‐2‐iodobenzene 2 to obtain 3 followed by cyclization using polyphosphoric acid to get the 1,4,5,8‐tetrafluoroacridone 4. Common synthetic strategies for converting 4 to the 1,4,5,8‐tetrafluoroacridine 5 were unsuccessful and the transfer hydrogenation approach proved to be most fruitful. 1,4,5,8‐Tetrafluoroacridone 4 can be N‐methylated to give 9. The investigation into the photophysical properties of 4, 5, and 9 revealed that the average photoluminescence (PL) lifetime of the acridine derivatives was longer in the aqueous medium than in ethanol and methanol, indicating the influence of the solvent environment on the excited‐state dynamics. To assess their potential therapeutic applications, the cytotoxic activity of these compounds was evaluated against AGS and IMR‐32 cells, and compound 9 showed significant activity. The addition of methyl group to the acridone was found helpful in enhancing the solubility and biological activity. [ABSTRACT FROM AUTHOR]

Herein we have developed a heterogeneous catalyst for synthesizing various anticancer and antidiabetic polyhydroquinoline derivatives via heterocyclic synthesis under solvent-free conditions at mild temperatures. This approach eliminates the need for complex cleanup or column chromatography, thus minimizing waste production. Moreover, the catalyst can be recovered and reused up to multiple times without compromising product yields, demonstrating its sustainability and environmental friendliness. Additionally, we evaluated each synthetic derivative for anticancer and antidiabetic activities. Initial assays revealed that certain derivatives exhibit promising inhibition against human breast cancer cells, suggesting their potential as lead structures for future anticancer agents. Furthermore, the synthesized derivatives were assessed for antidiabetic activity, showing superior efficacy. Notably, derivatives containing –H, –CH3, and –OCH3 substituents demonstrated excellent anticancer activity, while derivatives containing –H and –Br substituents showed notable antidiabetic activities, highlighting their therapeutic potential. Thus, our study presents an effective and sustainable approach for synthesizing polyhydroquinoline derivatives, emphasizing the catalyst's dual benefits in organic synthesis and medicinal chemistry applications. [ABSTRACT FROM AUTHOR]

A new variant of Fisher indole synthesis involving Bronsted acid-catalyzed hydrohydrazination of unactivated terminal and internal acetylenes with arylhydrazines is reported. The use of polyphosphoric acid alone either as the reaction medium or in the presence of a co-solvent appears to provide the required balance for activating the C–C triple bond towards the nucleophilic attack of the hydrazine moiety without unrepairable reactivity loss of the latter due to competing amino group protonation. Additionally, the formal hydration of acetylenes to the corresponding ketones occurs under the same conditions, making it an alternative approach for generating carbonyl groups from alkynes. [ABSTRACT FROM AUTHOR]

Copyright of Tikrit Journal of Engineering Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To promote the application of economical and sustainable polyphosphoric acid (PPA)-modified asphalt in road engineering, styrene-butadiene block copolymer (SBS), styrene-butadiene rubber (SBR), and PPA were used to prepare PPA/SBS and PPA/SBR composite-modified asphalts, which were tested and the data analyzed. Fourier transform infrared spectroscopy (FTIR) tests and thermogravimetric analysis (TG) tests were carried out to study the modification mechanisms of the composite-modified asphalts, and the high-temperature performance of the PPA-modified asphalt and asphalt mixtures was analyzed by dynamic shear rheology (DSR) tests and wheel tracking tests. A gray correlation analysis and a back-propagation (BP) neural network were utilized to construct a prediction model of the high-temperature performance of the asphalt and asphalt mixtures. The test results indicate that PPA chemically interacts with the base asphalt and physically integrates with SBS and SBR. The PPA-modified asphalt has a higher decomposition temperature than the base asphalt, indicating superior thermal stability. As the PPA dosage increases, the G*/sinδ value of the PPA-modified asphalt also increases. In particular, when 0.6% PPA is combined with 2% SBS/SBR, it surpasses the high-temperature performance achieved with 4% SBS/SBR, suggesting that PPA may be a good alternative for polymer modifiers. In addition, the creep recovery of PPA-modified asphalt is influenced by the stress level, and as the stress increases, the R-value decreases, resulting in reduced elastic deformation. Furthermore, the BP neural network model achieved a fit of 0.991 in predicting dynamic stability, with a mean percentage of relative error (MAPE) of 6.15% between measured and predicted values. This underscores the feasibility of using BP neural networks in predictive dynamic stability models. [ABSTRACT FROM AUTHOR]

For the last 20 years, researchers have been looking for ways to modify asphalt binders to improve their rheological and thermophysical properties. The application of composite modifiers to enhance the rheological properties of asphalt binders offers a potential remedy for this significant issue. Because of this, this study looked at how composite modifiers affected the plain binder's rheological characteristics. This study examined the rheological properties of unmodified and modified binders using a variety of formulations to blend modifiers including linear styrene-butadiene-styrene (SBS), radial SBS, Elvaloy, and polyphosphoric acid (PPA). The effect of PPA on the properties of polymer-added binders at low temperatures was investigated. Additionally, modifications using PPA aim to reduce the polymer content. Based on traditional performance classification (PG) and multiple stress creep recovery (MSCR) systems, original, rolling thin film oven–aged, and pressure aging vessel–aged binders were divided into three groups using a dynamic shear rheometer (DSR). The performance of binders at low temperatures was also assessed using the bending beam rheometer (BBR). All of the study's additions were discovered to have enhanced the neat binder's high-temperature capabilities. The elastic property of the neat binder was increased by the addition of Elvaloy and PPA. Results showed that, although the PPA modifier reduced the hardness of neat asphalt binder at low temperatures, other additives did not show significant effects on the hardness of the binder. The MSCR procedure was successfully utilized to grade all of the binders, but it appears that some binders and conditions do not fit the MSCR protocol's "percent difference" criterion. According to the study's findings, SBS can be replaced by 611 elastomer to enhance the performance of binders at high and moderate temperatures. [ABSTRACT FROM AUTHOR]

The mechanism of acylamination of arenes with nitroalkanes in polyphosphoric acid has been clarified. The influence of the concentration of polyphosphoric acid, the structure of the starting compounds, and temperature on the result of the Beckmann rearrangement, which makes it possible to shift the reaction towards either benzamides or anilides, has been assessed. [ABSTRACT FROM AUTHOR]

Developing high-performance and low-cost protein purification materials is of great importance to meet the demands for highly purified proteins in biotechnological industries. Herein, a facile strategy was developed to design and construct high-efficiency protein absorption and separation media by combining aerogels' molding techniques and impregnation processes. Poly (ethylene-co-vinyl alcohol) (EVOH) nanofibrous aerogels (NFAs) were modified by grafting butane tetracarboxylic acid (BTCA) over them in situ. This modification was carried out using polyphosphoric acid as a catalyst. The resulting EVOH/BTCA NFAs exhibited favorable comprehensive properties. Benefiting from the highly interconnected porous structure, good underwater compressive properties, and abundant absorption ligands, the obtained EVOH/BTCA NFAs possessed a high static absorption capacity of 1082.13 mg/g to lysozyme and a short absorption equilibrium time of about 6 h. A high saturated dynamic absorption capacity for lysozyme (716.85 mg/g) was also realized solely by gravity. Furthermore, EVOH/BTCA NFAs displayed excellent reusability, good acid and alkaline resistance, and unique absorption selectivity performance. The successful synthesis of such aerogels can provide a potential candidate for next-generation protein absorbents for bio-separation and purification engineering. [ABSTRACT FROM AUTHOR]

In order to investigate the dynamic mechanical properties of polyphosphoric acid (PPA) and SBS co-modified asphalt mixtures, uniaxial compression dynamic modulus tests were conducted. The influences of temperature and frequency on the dynamic modulus and phase angle were analyzed. Additionally, dynamic modulus and phase angle master curves were constructed based on the modified Havriliak-Negami (HN) model. A comparative analysis was also performed with SBS-modified asphalt mixtures. The results indicate that both types of asphalt mixtures exhibit similar trends in dynamic modulus and phase angle variations with changes in temperature and frequency. The HN model accurately fits the master curves of dynamic modulus and phase angle for both asphalt mixtures. In comparison to SBS-modified asphalt mixtures, the phase angle of PPA+SBS co-modified asphalt mixtures decreases at -10, 20, and 50 °C, while the dynamic modulus decreases at -10 °C, changes minorly at 20 °C, and increases at 50 °C. Over a wide frequency range, PPA+SBS co-modified asphalt mixtures exhibit increased dynamic modulus and decreased phase angle at high temperatures and low frequencies, while they show decreased dynamic modulus and relatively stable phase angle at low temperatures and high frequencies. These findings suggest that PPA+SBS comodification endows asphalt mixtures superior dynamic mechanical properties. [ABSTRACT FROM AUTHOR]

The present investigation mainly aimed at analyzing the rutting responses of polymer-modified binders with and without Polyphosphoric Acid (PPA) and by considering increased loading times in the Multiple Stress Creep and Recovery (MSCR) tests. Typical high pavement temperatures of 52, 58 and 64 °C were chosen, and these loading times varied from 1.0 to 8.0 s (1/9, 2/9, 4/9 and 8/9 s). Formulations with styrene–butadiene–styrene copolymer—SBS (AC + SBS and AC + SBS + PPA), ethylene vinyl acetate copolymer—EVA (AC + EVA and AC + EVA + PPA) and Elvaloy® terpolymer (AC + Elvaloy + PPA) were prepared, and the high PG grade of all these formulations was controlled at 76-XX. In general, the AC + Elvaloy + PPA was the best formulation to counteract rutting at longer creep times—especially 4/9 and 8/9 s—due to the presence of a strong and stable polymer network within the binder matrix. Moreover, the AC + SBS + PPA was able to deal with traffic levels similar or slightly higher than those of the AC + SBS, and this might be attributed to the hardness imparted by PPA modification and the presence of more stable polymer networks in the AC + SBS + PPA. On the other hand, the AC + EVA + PPA was found to be less rut resistant than the AC + EVA, and none of the EVA-modified binders depicted sufficient degrees of stiffness to deal with heavier and slow-moving traffic levels—mainly for temperatures of 58 °C or higher and loading times of 4/9 s or longer. Overall, the data indicate that binders with high degrees of stiffness at standardized MSCR loading conditions (1/9 s) do not necessarily perform well at longer creep times. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to synthesize 6-ethyl-4-hydroxyquinolin-2(1H)-one as a new enol-type coupling component in the preparation of some 3-arylazo-4-hydroxyquinolin-2(1H)-one dyes and evaluate the solvent effects on their absorption in ultraviolet-visible spectra. Design/methodology/approach: 6-Ethyl-4-hydroxyquinolin-2(1H)-one was synthesized by thermal cyclocondensation reaction of N, N′-bis(4-ethylphenyl) malonamide at 130–140°C in polyphosphoric acid. This compound was then applied in the azo-coupling reaction with some aniline-based diazonium salts, so as to prepare seven new mono-heterocyclic azo dyes. The structures of the compounds were confirmed using mass spectroscopic technique. Fourier transform infra red (FT-IR) and 1H proton nuclear magnetic resonance (1H NMR) and carbon-13 nuclear magnetic resonance (13 C NMR) studies on the structure of the azo compounds revealed that they exist as two E- and Z-isomers of hydrazone tautomer both in solid and solution state. The effects of acid and base on the visible absorption spectra of the dyes were also evaluated and discussed. Findings: Ultra violet-visible UV-vis absorption spectra of the dyes didn't show significant variation by changing of solvents because of intramolecular H-bonding between proposed hydrazone forms and 2- and 4-keto functions in their structures. The spectra of the dyes were not sensitive to the addition of acid but were very sensitive to base. Originality/value: The synthesized 3-arylazo-4-hydroxyquinolin-2(1H)-one dyes are new members in the 4-hydroxyquinolin-2(1H)-one azo dyes family, where very few details regarding the synthesis of such dyes are reported before in the literature. They are unique in terms of synthesis and spectral properties. [ABSTRACT FROM AUTHOR]

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Helical morphologies are widely observed in nature, however, it is very challenging to prepare artificial helical polymers. Especially, precisely understanding the structure information of artificial metal‐free helical covalent inorganic polymers via single‐crystal X‐ray diffraction (SCXRD) analysis is rarely explored. Here, we successfully prepare a novel metal‐free helical covalent inorganic polymer ({[Te(C6H5)2] [PO3(OH)]}n, named CityU‐10) by introducing angular anions (HOPO32−) into traditional tellurium‐oxygen chains. The dynamic reversibility of the reaction is realized through the introduction of organic tellurium precursor and the slow hydrolysis of polyphosphoric acid. High‐quality and large‐size single crystals of CityU‐10 have been successfully characterized via SCXRD, where the same‐handed helical inorganic polymer chains form a pseudo‐two‐dimensional layer via multiple hydrogen‐bonding interactions. The left‐handed layers and right‐handed layers alternatively stack together through weak hydrogen bonds to form a three‐dimensional supramolecular structure. The single crystals of CityU‐10 are found to display promising optical properties with a large birefringence. Our results would offer new guidelines for designing and preparing new crystalline covalent polymers through tellurium‐based chemistry. [ABSTRACT FROM AUTHOR]

To develop a novel self-healing asphalt binder and address the challenge of poor performance of waste tire pyrolysis oil-modified asphalt at high temperatures, this study employed polyphosphoric acid and waste tire pyrolysis oil for composite modification of asphalt. Subsequently, comprehensive evaluations of the modified asphalt were conducted using experimental techniques such as temperature sweep, time sweep, differential scanning calorimetry, Fourier-transform infrared spectroscopy, and fluorescence microscopy. The entropy weight method was utilized to determine the optimal dosage of modifiers in the asphalt binder and evaluate the comprehensive performance of the modified asphalt. Experimental results indicate that the introduction of polyphosphoric acid not only effectively maintains the self-healing properties of the modified asphalt but also significantly improves the negative impact of waste tire pyrolysis oil on the high-temperature performance of the asphalt binder. Analysis using the entropy weight method revealed that the optimal dosages of 2% polyphosphoric acid and 4% waste tire pyrolysis oil served as modifiers, resulting in the superior overall performance of the modified asphalt at these concentrations. In conclusion, the development of polyphosphoric acid/waste tire pyrolysis oil composite modifiers offer a novel avenue for the sustainable enhancement of asphalt modification.

This research focuses on the aging resistance properties of asphalt, which are crucial for determining the lifespan of asphalt pavement. To combat aging, waste tire pyrolysis oil (TPO) is often added to asphalt, enhancing its resistance to aging but compromising high-temperature performance. This study offered a pioneering solution by integrating TPO with polyphosphoric acid (PPA) to address these issues. In this study, we conducted a series of tests to characterize the properties of PPA/TPO modified asphalt, including temperature sweep and bending beam rheometer tests. The results demonstrated that the presence of PPA in the PPA/TPO modified asphalt could improve its high-temperature performance while maintaining its low-temperature properties. Moreover, PPA in the PPA/TPO modified asphalt enhanced the modified asphalt’s resistance to fatigue and deformation during the aging process, while the presence of TPO effectively reduced the impact of thermo-oxidative aging on the modified asphalt during the aging process. Additionally, physicochemical interactions between the base asphalt and modifiers were observed before and after aging. In summary, this study had offered an innovative method to enhance the anti-aging properties of asphalt, and had provided more options for sustainable, environmentally friendly roads.

This article describes the synthesis of 5-Methoxy-2-acetyl-1-naphthol, a compound that can be used to create the quinone moiety found in daunomycinone. The authors sought an alternative procedure for the synthesis of this compound that would use readily available starting materials and improve yields. They developed a method that involved converting 5-methoxy-1-tetralone to 5-methoxy-1-naphthol, acetylating it to obtain 5-methoxy-1-naphthyl acetate, and then subjecting it to a Fries rearrangement to produce 5-Methoxy-2-acetyl-1-naphthol. The authors achieved an overall yield of 50% using this method. [Extracted from the article]

Cinnamides are common core structures that exist in a great number of pharmaceuticals and natural products. The development of efficient methods for preparing cinnamides is in great need. We report herein an efficient polyphosphoric acid (PPA)-promoted direct aldol condensation of an amide for the convenient and straightforward preparation of cinnamides. A variety of cinnamides were obtained in moderate-to-excellent yields (65–89%). This strategy features the use of equivalent amides and a short reaction time.

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To address the issue of bad compatibility between a single polymer modifier and asphalt and high preparation cost, the composite modified asphalt with polyphosphoric acid (PPA) and SBS as a modifier was prepared. Basic properties, viscosity characteristics, high-temperature and low-temperature rheological performance, and aging-resistant performance of SBS/PPA composite modified asphalt were comprehensively evaluated, and the best content of PPA was obtained through the experimental results below. By performing an infrared spectrum test and a scanning electron microscope test, structural changes and modifying mechanisms of composite modified asphalt were analyzed. The results indicate the optimal PPA content is 0.75%. After adding PPA, the penetration and ductility of composite modified asphalt were reduced, while the softening point increased. At 135 °C, the viscosity was 1.2 times that of SBS modified asphalt. The average weight loss ratio was 0.163%. When the content of PPA was 0.75% and 1%, the rutting factor increased significantly. Therefore, PPA can not only improve the thermal oxidation aging resistance of asphalt, it can also improve the shear resistance, high-temperature performance, and temperature sensitivity of asphalt. Between 1027 and 1150 cm−1, the composite modified asphalt forms a new absorption peak, and from 1610 cm−1, the absorption peak presents an upward trend, suggesting that PPA reacts chemically with asphalt, produces the new substance, and also increases a large number of hydrocarbon components with chain structure. The surface appearance of the compound modified asphalt gradually presents a smooth wrinkle state due to the increase of PPA, so the issue of easy segregation of SBS in asphalt is improved. [ABSTRACT FROM AUTHOR]

The synergistic fire retardancy of modified melamine resin with pentaerythritol (MF‐PER, a novel green and effective triazine charring agent), and ammonium polyphosphate (APP) in polypropylene was investigated by UL‐94 test, LOI measurement, and cone calorimetry test. It is found that the synergism of MF‐PER is obviously better than pentaerythritol (PER). MF‐PER/APP imparts a fire retardancy mainly by the following mode: in burning process, MF‐PER, and APP are first pyrolyzed respectively into polyols and polyphosphoric acid, which is esterified to form phosphoric ester, and the inert gases make the molten residues foaming; When the temperature increases, and polyphosphoric acid is dehydrated to polymetaphosphoric acid, which dehydrates phosphoric ester to form an intumescent char layer, inducing a fire retardant effect by barrier effect. The graphitization degree of the cone calorimetry test residues of the FR‐PP with MF‐PER is higher than that with PER, which leads to a better synergism. Highlights: Melamine formaldehyde resins modified with pentaerythritol (MF‐PER) as a novel triazine charring agent was designed and synthesized.MF‐PER is synthesized by solid phase method and using hexahydroxymethyl melamine (HMM) instead of cyanuric chloride as raw material, so the emission of three wastes in its synthesis process is very little, only a small amount of formaldehyde and water are produced.MF‐PER has excellent synergistic fire retardancy with APP in polypropylene.The highly efficient and environmentally benign charring agent show great potential for developing more efficient and eco‐friendly IFR. [ABSTRACT FROM AUTHOR]

Annually tons of waste engine oil is wasted or dumped in environmentally unfriendly ways. Asphalt binder has been modified with waste engine oil previously and showed, lower consistency, lower moisture damage resistance at higher dosages, and impaired high-temperature performance. In the current study, three different additives were added to solve these issues associated with waste engine oil-modified bitumen. Elvaloy, polyphosphoric acid (PPA), and hydrated lime (H-L) were used as polymer, chemical, and filler-type additives. Waste engine oil-modified bitumen combined with all three types of additives was evaluated using conventional viscosity, moisture susceptibility, dynamic mechanical, and chemical testing. Results showed that waste engine oil inclusion decreased the consistency of binder, reduced viscosity, and impaired high-temperature performance. Elvaloy's addition to waste engine oil-modified bitumen made it less sensitive to temperature changes, increased the performance grade, improved the stiffness, and enhanced the resistance against rutting and moisture-induced damages. Polyphosphoric acid addition refined the consistency of binder modified with waste engine oil. It drastically increased the complex modulus values and decreased phase angle values by stiffening the binder. PPA enhanced the moisture susceptibility of asphalt and improved its high-temperature performance. Hydrated lime improved moisture resistance and bonding strength but showed less effectiveness in improving high-temperature performance at lower dosages. The results conclude that binder modification with waste engine oil can be effective with other additives like polyphosphoric acid, Elvaloy, and hydrated lime. [ABSTRACT FROM AUTHOR]

In the present study, stress sensitivity of modified binders in the multiple stress creep and recovery (MSCR) test and its relationship with rutting resistance of the asphalt mixtures are investigated. For this purpose, different groups of styrene butadiene styrene (SBS), polyphosphoric acid (PPA) and SBS + PPA modified binders were produced; in each of which, the binders have the same continuous high temperature performance gradings (PGs) and linear viscoelastic (LVE) properties. The MSCR tests were performed at 40°C, 55°C, and at the PG temperatures of the modified binders to consider a wide range of high pavement temperatures. To depict the stress sensitivity, stress levels of 12.8, 25.6, and 40 kPa were added to the MSCR standard procedure and the non-recoverable compliance (Jnr) and percent recovery (R) parameters were obtained at all the stress levels applied. To study the rutting resistance of asphalt mixtures prepared with the same asphalt binders, the flow number (FN) and |E*| parameters were determined at 40°C and 55°C, through the dynamic creep and dynamic modulus performance tests, respectively. Results of the MSCR test show that at the temperature range considered, the standard stresses are not sufficient to enter the modified binders into nonlinear region, thus higher stress levels should be applied to assess the nonlinearity and address the true rutting potential. Results of the mixtures performance tests show great correlations with the results of the MSCR of the modified binders at the nonlinear stress levels, especially with the Jnr parameter, regardless of the test temperatures. [ABSTRACT FROM AUTHOR]

A large amount of soybean oil (20%–30% mass ratio of neat asphalt) was selected to partially replace petroleum asphalt. The high-temperature behavior of soybean oil bioasphalt was enhanced by polyphosphoric acid (PPA). Polyphosphoric acid/soybean oil composite modified asphalt (PSMA) was prepared. Temperature sweep, frequency sweep, multiple stress creep recovery, and bending beam rheometer tests were conducted to reveal the rheological behavior. Fourier infrared spectroscopy (FTIR), scanning electron microscope, and fluorescence microscope tests were carried out to reveal its microstructure characteristic. The results proved that polyphosphoric acid obviously increased the high-temperature properties of soybean oil bioasphalt. Compared with the neat asphalt at 0.1 kPa, the recovery rates of 20% bio/6% PPA, 25% bio/6% PPA, and 30% bio/6% PPA increased by 139.2%, 113.5%, and 86.4% respectively. PSMA was less sensitive to temperature and loading frequency, with remarkable elastic recovery and antirutting degeneration ability. PSMA could maintain excellent low-temperature crack resistance at −18°C. PSMA had better rheological properties when soybean oil and PPA were 20%–25% and 4%–6%, respectively. The FTIR tests verified that some new functional groups emerged in PSMA. There were evenly distributed fluorescent materials in the soybean oil bioasphalt under the fluorescence microscope. Under the modification effect of PPA, soybean oil and PPA could be evenly dispersed in PSMA. Laboratory tests verified the superior properties of bioasphalt with high content soybean oil. [ABSTRACT FROM AUTHOR]

The objective of this study was to explore the effect of polyphosphoric acid (PPA) on the low-temperature creep properties of styrene–butadiene-styrene (SBS) and crumb rubber (CR)-modified asphalt binder. PPA-SBS and PPA-CR composite-modified asphalt with different PPA contents were prepared by a high-speed shear method. The low-temperature properties of composite-modified asphalt were studied by bending beam rheometer (BBR) test, and the test results were fitted by the Burgers model to assess the creep property of the asphalt. From the test results, it is demonstrated that the low-temperature properties of polymer-modified asphalt were weakened after PPA was added. At low temperatures, the stiffness modulus (S) of PPA-CR composite-modified asphalt was half that of PPA-SBS, and the creep rate (m) was more than 9.4% higher. The results of relaxation time ($\lambda$ λ), dissipated energy ratio (DER), and the derivative of creep compliance (J'(t)) showed that the creep property of PPA-CR composite-modified asphalt is better than that of PPA-SBS and SBS-modified asphalt at low temperatures. Moreover, the antiaging ability of polymer-modified asphalt was also ameliorated by incorporating PPA, regardless of SBS or CR. [ABSTRACT FROM AUTHOR]

In order to address the high preparation cost of styrene–butadiene–styrene block copolymer (SBS) modified asphalt, four kinds of polyphosphoric acid (PPA) content (0%, 0.5%, 0.75%, and 1% PPA by weight of the matrix asphalt) were selected to prepare composite modified asphalt with better high-temperature performance. The physical properties of composite modified asphalt were evaluated by conventional performance tests. The rheological properties of composite modified asphalt were evaluated by dynamic shear rheometer (DSR) test and bending beam rheometer (BBR) test. The synergistic modification mechanism of PPA and SBS was revealed by the Fourier transform infrared spectroscopy test. The results show that with the increase of PPA content, the penetration of PPA/SBS composite modified asphalt is reduced by 20.92%, 25.07% and 28.94%, respectively, compared with matrix asphalt, and the softening point is increased by 5.46%, 22.69% and 34.03%, respectively. In addition, PPA can improve the thermal oxidative aging resistance of asphalt. PPA can improve the shear resistance, high-temperature performance and temperature sensitivity of asphalt. At 82 °C, compared with SBS modified asphalt, the phase angle of PPA/SBS composite modified asphalt can be decreased by 8.63%, 13.23% and 19.24%, respectively, and G*/sinδ can be increased by 41.97%, 67.62% and 70.97%, respectively. SBS mainly exists in asphalt in the form of physical blending, and PPA has a new chemical reaction with asphalt, which increases the macromolecules and chain hydrocarbon components in asphalt, and the macroscopic performance is the improvement of high-temperature performance of asphalt. However, PPA has a negative effect on the low-temperature performance of the SBS modified asphalt. [ABSTRACT FROM AUTHOR]

Porous metal–organic frameworks (MOFs) have started to gain attention because of their high crystallinity, porosity and structural designability, and they can facilitate proton conduction, but the poor membrane forming ability of MOFs limits their application. In this work, composite membranes based on poly (2,5-benzimidazole) (ABPBI) are focused, and the polymer ABPBI was synthesized from its monomer by solution polycondensation method using polyphosphoric acid (PPA) as solvent. Copper-trimesic acid (Cu-TMA) based metal-organic framework (MOF) was prepared by solvothermal synthesis. Varying ratios of MOF were incorporated into the ABPBI polymer matrix to develop a polymer electrolyte membrane (PEM) by solvent casting technique. Sulfonated composites were obtained by immersing the membranes in 20% sulfuric acid and the membranes were used to characterize the crystallographic structure and surface morphology by XRD and SEM. The membrane's mechanical, thermal and physicochemical properties, like tensile strength, thermogravimetric analysis, contact angle, water uptake, swelling ratio, ion exchange capacity, oxidative stability and proton conductivity, have also been evaluated. The 3 wt% Cu-TMA loaded membrane exhibited the highest proton conductivity of 0.039 S cm−1 at 80 °C, whereas the neat sABPBI showed 0.024 S cm−1. Cu-TMA/sABPBI based PEMs are good candidates for polymer electrolyte membrane fuel cells, as shown by their water uptake and ion exchange capacity values of 21.58% and 1.66 meq g−1. • Cu-MOF loaded sABPBI based composite membrane has been prepared for the first time. • The developed membrane displayed high conductivity of 0.039 S cm−1 at 80 °C. • The Cu-TMA/sABPBI composite membrane achieved 62% higher conductivity than the pristine membrane. • Physicochemical studies revealed a very high water absorption capability (21.6%) and radical stability (89.6%). [ABSTRACT FROM AUTHOR]

The reaction mixture was cooled at 25-30 °C, and then was added THF (5.6 L). 2-Carboxybenzaldehyde (V, 2.8 kg, 18.91 mole) was diluted in 4.20 L THF and slowly added to the reaction mixture over 2 hours at 25-30 °C. After completion of the reaction, 50.0 L DCM was added and the reaction mixture was poured into 50.0 L cold water at 15-30 °C. After the addition, the reaction mixture was maintained at 25-30 °C for 12 hours and completion of reaction confirmed by TLC (mobile phase: CHCl SB 3 sb ). Dibenzosuberone-based tricyclic compounds are promising anti-fungal and anti-histaminic agents,[[1], [3], [5]] exemplified by the dichloro-substituted 1-(5H-dibenzo [a, d] cyclohepten-5-yl)-1H-imidazole compound, Eberconazole (Figure 1). [Extracted from the article]

Finding beneficial uses for waste plastics has been an environmental challenge for municipalities. A limited number of studies have investigated the performance of asphalt mixtures containing plastic waste in cold regions that experience freeze-thaw cycling. The objective of this study is to evaluate the impact of adding two types of recycled plastic pellets on the high- and low-temperature performance of bituminous binders. Nylon-based (NP) and polyester-based (PP) recycled plastic pellets were used in this study. A PG 58-28 bituminous binder was modified by different dosages of NP and PP plastic pellets. The impact of adding Elvaloy copolymer and polyphosphoric acid on the modified binders was also investigated. Results showed that using recycled plastic pellets as a modifier for bituminous binders improved their elastic response and rutting resistance without affecting their low-temperature performance. The PP modifier showed better elastic behavior and rutting resistance than the NP modifier. [ABSTRACT FROM AUTHOR]

Ethylene vinyl acetate copolymer (EVA) was modified by expandable graphite (EG) and polyphosphoric acid (PPA) in melt state and the obtained EVA/EG/PPA composite was studied regarding its fire behavior, thermal endurance, water resistivity, processability, and mechanical property. The outcomes evince that the combination of EG and PPA in proper mass ratio can improve fire retardancy, thermal stability, processability, and reduce smoke and toxic gas releases of EVA upon combustion significantly. The EG/PPA combination exhibits very high flame retardant efficiency to EVA in that only 10 wt% loading is enough to make EVA obtain V‐0 rating in UL‐94 test. Moreover, the flame‐retarded EVA/EG/PPA composite displays excellent water resistance and acceptable mechanical property. The EVA/EG/PPA (90/7.5/2.5) composite can produce coherent intumescent char on composite surface, which has good heat endurance and hinders heat transmission from fire to interior of composite. The flame retardation occurs in condensed phase and the intumescent char plays a pivotal role. The presence of PPA endows EVA composite with good melt flowability, which has presented a striking contrast to other flame retardants. Highlights: The combination of EG and PPA has very high flame retardant efficiency to EVA.The EVA/EG/PPA composite has better fire safety and processability than EVA.The EVA/EG/PPA composite still maintains acceptable mechanical property.The expanded char from EVA/EG/PPA composite hinders heat transfer effectively. [ABSTRACT FROM AUTHOR]

A series of polybenzimidazoles (PBIs) incorporated main chain 4-pyridine bridge groups were synthesized from 4,4′-([4,4′-bipyridine]-2,6,-diyl)bis (benzene-1,2-diamine) which reacted with four different diacids like isophthalic acid,4,4′-Oxibis benzoic acid, 5-amino isophthalic acid and 2,5-pyridine dicarboxylic acid using polyphosphoric acid as solvent. A process termed dispersion polymerizationhas been developed to prepare PBIs.For the membranepreparation, 4-pyridine-bridge polybenzimidazole (Py-PBI) productswere re-dissolved in dimethyl sulfoxide and cast. The polymer structure characterization included FT-IR, UV, Powder XRD, Water Uptake, Swelling Ratio, Ion exchange capacity, Acid doping, Acid leaching, Oxidative stability, and Polymer inherent viscosity find out by using Ubbelohde viscometer whilethermal stability assessments via thermogravimetric analysis. The Py-PBI-based polymer electrolyte membranes' mechanical properties measurement showed that the 4-pyridine-bridge PBIs membranes were flexible, thermally stable, and mechanically strong when compared with conventional PBI. The current-voltage (I-V) characteristics of the 4-Py-PBI membrane show that the conductivity of the 4441P membrane is 0.546 S cm−1. Graphical Abstract [ABSTRACT FROM AUTHOR]

Steam-assisted gravity oil drainage (SAGD flooding) is a cutting-edge technology for the development of oils which is gradually replacing steam huff and puff and is being used more and more widely. Low-permeability interlayers are generally developed in oil reservoirs in China, which may shield the migration of steam, oil and gas. Targeted acidizing fracturing was proposed to break through the low-permeability interlayers, and hence, the problem that the hindrance to the expansion of the steam chamber led to heat loss and seriously affected the development effect could be solved. A typical kind of well with SAGD flooding actually applied in China, Shuyi District of Liaohe Oilfield, was taken as the example for studying the optimization of crack parameters. Based on the study of reservoir sensitivity characteristics in this well, the formulations of working fluids for targeted acidizing fracturing were developed by optimizing the weight percentages of main acid solution and additives. The formula of '4% hydrochloric acid + 2% polyphosphoric acid + 5% fluoroboric acid + 4% acetic acid' could be used as the acidizing fracturing working fluid for typical blocks of the Shuyi District of Liaohe Oilfield, which can increase the permeability of the natural core by 40.19–57.06%. Studies on targeted acidizing fracturing are beneficial for enhancing the oil recovery of oil reservoirs. [ABSTRACT FROM AUTHOR]

Before using basic oxygen furnace slag (BOFS) in any engineering application, it is important to determine its properties. The chemical composition, mineralogy, and physical properties of BOF slag are subject to large fluctuations as a result of different raw additives, different compositions of the molten iron used for producing the steel, oxygen stirring of a molten pool, uneven temperature fields, and other complex physical conditions. Thus, in this research, the engineering properties of BOF slag aggregates with different ages were identified, and then the feasibility of BOF slag aggregates in mortar application was investigated. It was found that stockpiled BOFS was harder than fresh BOF slag, which had lower aggregate crushing values and lower LA abrasion values. Also, stockpiled BOFS showed less expansion than fresh BOF slag regardless of water and 1 M NaOH solution immersion. The chemical reaction between f-CaO, f-MgO, and water due to weathering in the field extremely reduced the expansion of BOFS submerged in water. BOFS may contain reactive silica, which causes an alkali–silica reaction (ASR). Stockpiled BOFS (100%, 75%, 50%, 25%) used as a mineral filler in asphalt concrete mix brought about low tensile strength at break up (crack), low compressive strength at +50 °C, poor cohesion, and residual porosity. However, these parameters were partially improved with the use of a thermostable adhesive additive for road bitumen based on polyphosphoric acid esters. The comprehensive assessment in this study indicates that while some mixtures meet the specified criteria for certain properties, there are challenges, particularly regarding crack resistance and cohesion, that need to be addressed to fully align with the standard. Adjustments to the mixture proportions, the exploration of alternative additives, and the use of different types of fillers may be necessary to achieve the desired properties, especially in terms of crack resistance and cohesion. [ABSTRACT FROM AUTHOR]

A number of new alkaloid-like phenylfuroacridones were synthesized by cyclization in polyphosphoric acid of 2-, 3 -, 4-(2-oxo-2-phenylethoxy)acridones, which, in turn, were obtained by O-alkylation of the corresponding 2-, 3-, 4-hydroxyacridones with phenacyl bromide. Biological studies showed that phenylfuroacridones exhibited a low antibacterial activity against the test strain Candida albicans. [ABSTRACT FROM AUTHOR]

Polyphosphoric acid (PPA) and styrene–butadiene–styrene (SBS) were adopted to produce PPA-SBS-modified bio-blend bitumen, which achieved excellent mechanical performance. However, its long-range performance, such as the fatigue and thermal cracking behavior under long-term thermal oxidation, is not well understood. Therefore, a pressure aging vessel (PAV) system was applied to simulate the aging behavior of the bitumen under the action of thermal oxidation. Then, a linear amplitude sweep (LAS) test combined with a viscoelastic continuum damage (VECD) model was applied to investigate the fatigue properties of the bitumen. Moreover, a bending beam rheometer (BBR) test was conducted to evaluate the thermal cracking resistance of the bitumen before and after PAV aging. Meanwhile, an atomic force microscope (AFM) was applied to observe the microscopic topography. The results show that the original compound-modified bitumen can bear more fatigue damage than that of the control bitumen at the failure point, and it also has excellent fatigue resistance at 2.5%, 5%, 7.5%, and 10% applied strain. Moreover, the VECD model can accurately predict the fatigue life of the bitumen under different applied strains. The variation ratio of stiffness modulus for the compound-modified bitumen is below that of the control bitumen after PAV aging, so it shows a better anti-aging performance. Finally, the AFM test shows that PPA and bio-bitumen decrease the heterogeneity of the bitumen, reducing the difference between phases. [ABSTRACT FROM AUTHOR]

The acidity constant values (Ka or pKa) and polyionic species distribution are valuable tools to identify the extent of ionization and complexing properties of polyionic species. They are of great importance to predict the charged state of analyte and choose the appropriate condition in the design of functional materials for their intended purposes. Polyphosphates, being one of the anionic types of polyelectrolytes, have attracted interest for utilization in a quite wide range of applications in the boundaries of nanomaterial, bio-analytical chemistry, and physical sciences. In this study, it is aimed to estimate the intrinsic pKao of polyphosphoric acid (PPH) with high molar mass and the charge of its polyanionic conjugate base (PP−), (Z PP -) , according to activity coefficient estimation by Davies using potentiometric titration along with the theoretical consideration of Gran's approach. Besides, a series of PPH titration was simulated via CurTiPot and the data were further treated in MATLAB to visualize the 3-D pH surfaces of PPH/PP− pairs. As a result, the outcomes of experimental work and simulations were consistent very well, and pKao of PPH and Z PP - were found as 2.22 ± 0.01 and − 1.105 ± 0.003, respectively, at a 95% confidence interval. [ABSTRACT FROM AUTHOR]

The asphalt was modified with different amount of polyphosphoric acid(PPA), and the effects of PPA on the high-low temperature properties and aging properties of asphalt were studied, aging mechanism of PPA modified asphalt were analyzed by the means of chemical composition analysis and Fourier transform infrared spectroscopy(FTIR). The results show that with the increase of PPA dosage, the softening point and viscosity of the modified asphalt gradually increase, while the Fraass breaking point moves to the direction of lower temperature. The high and low temperature performance of modified asphalt are significantly improved. Compared with unmodified asphalt, the softening point increment, viscosity aging index and Fraass breaking point increment of PPA modified asphalt are obviously reduced after short-term thermal aging, long-term thermal aging and ultraviolet light aging, the penetration retention and ductility retention are significantly increased. The results of chemical composition analysis and FTIR indicate that PPA is able to promote the transformation of asphalt from resins to asphaltenes, and reduce the active components which prone to take place aging reactions in asphalt. The changes of aliphatic group, aromatic group, carbonyl group and sulfoxide group index of PPA modified asphalt in aging process are remarkably reduced, thereby possessing excellent anti-aging performance. [ABSTRACT FROM AUTHOR]

This study examines how aging affects the healing capacity of bituminous composites containing polyphosphoric acid (PPA). PPA is commonly used in bituminous composites to enhance its elasticity, however, PPA effectiveness highly depends on other constituents on the matrix and the environmental (internal and external) factors. In terms of internal factors, the interplay between PPA and various bitumen modifiers have been extensively studied. Here, we study how external factors such as exposure to ultraviolet radiation affect PPA's efficacy, measured in terms of change in bitumen's healing index. The study results showed that the introduction of PPA to bituminous composites significantly increases the bitumen healing index, however, the change in the healing index becomes less pronounced as aging progresses. The presence of additives such as taconite were found to affect the effect of PPA on bitumen's healing index. For instance, bitumens containing 30% taconite showed the highest increase in their healing index in the presence of PPA among studied scenarios. Overall, bitumen containing PPA had a higher healing index than those without PPA regardless of the extent of aging and dosage of modifiers. This, in turn, indicates that PPA is highly effective for enhancing bitumen healing. This can be attributed to the role of PPA in promoting intermolecular interactions within the bitumen matrix. [ABSTRACT FROM AUTHOR]

Bitumen's self-healing capability is critical to the bitumen industry's sustainable development. This work attempts to examine the self-healing property and fatigue behavior of bitumen using waste cooking oil (WCO) and polyphosphoric acid (PPA) in bitumen modification. Different components of WCO were mixed with PPA and bitumen for the initial modification. The linear amplitude sweep (LAS) test was used to evaluate the fatigue behavior of the modified bitumen. To assess the extent of bitumen healing after a fatigue-healing test, evaluation indicators, including fatigue life recovery (FLR), modulus recovery (MR), and dissipated energy recovery (DER), were selected. Meanwhile, a radar chart was used to analyze the integrated performance of WCO/PPA (WP)-modified bitumen. Lastly, the SARA fractions were separated from the bitumen to evaluate the modification mechanism. It was observed that the inclusion of PPA and WCO enhanced fatigue behavior. For 2% PPA and an intermediate component (IC) of WCO, the fatigue life of the LAS prediction model showed extreme values, with an increase of 669% over virgin bitumen. Regardless of the PPA concentration, a considerable increase in FLR, MR, and DER was seen in the bitumen processed with IC compared to virgin bitumen. Additionally, as the healing time was extended, the increment in the virgin bitumen's healing indicators was higher than that of the modified bitumen. SARA results indicated that adding PPA changes the bitumen from a soluble state to a gel state. An innovative approach has been proposed to promote sustainable development within the bitumen industry. [ABSTRACT FROM AUTHOR]

In recent years, casting molds made by sand-type additive manufacturing (AM) technology are increasingly being used to build prototypes and small-lot production casting products. The development of this technology aiming at Mass-production applications in the future is progressing through the advancement of AM technologies and casting technologies. The application to Mass production is expected to increase the potentials of the whole casting, by realizing more complicated internal structure, reducing product thickness and weight by improving the cavity precision, etc. One method which can meet such needs is the current AM technique using furan sand molds. It is performed on large molding machines and is based on the organic self-hardening process utilizing mainly furan binder. This 3D AM sand mold using furan binder (hereafter referred to as "furan AM sand mold") contains sulfurous acid gas generated by the thermal decomposition of the catalyst used or organic gases generated by the thermal decomposition of the cured binder during pouring. In some cases, it is necessary to take measures such as removal of the gases from the molds. Other issues also need to be improved in terms of the working environment and casting quality. Examples of practically applied 3D AM methods using inorganic binders are; ink jetting water to plaster or cement, or ink jetting water to coated sand (laminated sand coated with water glass). However, various challenges are met with these methods, such as lack of high-speed large 3D printers and mold collapsibility is difficult after pouring. Under these circumstances, we attempted to fill a furan AM sand mold with an inorganic binder consisting of phosphate and sulfate, and then sinter the sand mold in an atmosphere of 850°C so that the furan AM sand mold changes into inorganic mold. With this mechanism, strong bonded layers are formed by the formation of polyphosphoric acid by the high molecularization of phosphate and the fusion of sulfate, while the thermal decomposition of the cured furan binder is progressing. As a result, this transforms the sand mold into a mold composed of only the inorganic binder. The resultant mold has been found to be sufficiently practical with almost no gas generation even under the condition of 1000°C. As for the problem of mold breakage, when water is added to the mold, the sulfate that forms the adhesion layer dissolves in the water, and this action allows the mold to be collapsed easily. These results confirm that this mold has a balanced combination of good heat resistance, reduced harmful gases, and good mold collapsibility. [ABSTRACT FROM AUTHOR]

Conventional bitumen pavement is no longer suitable for handling increasing loads and weather variations, which cause road deterioration, Thus, the modification of bitumen has been suggested to counter this issue. This study provides a detailed assessment of various additives for modifying natural rubber-modified bitumen used in road construction. This work will focus on the use of additives with cup lump natural rubber (CLNR), which has recently started to gain attention among researchers, especially in rubber-producing countries such as Malaysia, Thailand and Indonesia. Furthermore, this paper aims to briefly review how the addition of additives or modifiers helps elevate the performance of bitumen by highlighting the significant properties of modified bitumen after the addition of modifiers. Moreover, the amount and method of application of each additive are discussed further to obtain the optimum value for future implementation. On the basis of past studies, this paper will review the utilisation of several types of additives, including polyphosphoric acid, Evotherm, mangosteen powder, trimethyl-quinoline and sulphur, and the application of xylene and toluene to ensure the homogeneity of the rubberised bitumen. Numerous studies were conducted to verify the performance of various types and compositions of additives, particularly in terms of physical and rheological properties. In general, additives enhance the properties of conventional bitumen. Future research should investigate CLNR because studies on its utilisation are limited. [ABSTRACT FROM AUTHOR]

The ultraviolet (UV) aging of asphalt is an important factor affecting the long-term performance of asphalt pavement, especially in high altitude cold regions. The current studies have reported that styrene butadiene rubber-modified asphalt (SBRMA) has a good cracking resistance at low temperatures. In addition, polyphosphoric acid (PPA) is an effective modifier that can enhance the anti-UV aging properties of asphalt. However, the understanding of the improvement mechanism of PPA on the anti-aging of SBRMA remains unclear. Therefore, this study aimed to evaluate the effect of PPA on the UV aging resistance of SBRMA. The rheological properties of PEN90 asphalt(90#A), SBRMA, and PPA/SBR modified (PPA/SBR-MA) before and after UV aging were evaluated by dynamic shear rheometer (DSR) and bending beam rheometer (BBR) tests. The molecular weight and chemical structure of 90#A, SBRMA, and PPA/SBR-MA were determined by Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC), and the interaction and modification mechanism of the modifiers were analyzed. The rheological analysis shows that the high and low temperature performances of SBRMA are improved by adding PPA, and PPA also significantly reduces the sensitivity of SBRMA to UV aging. The microscopic test results show that PPA has a complex chemical reaction with SBRMA, which results in changes in its molecular structure. This condition enhances SBRMA with a more stable dispersion system, inhibits the degradation of the polymer macromolecules of the SBR modifier, and slows down the aging process of base asphalt. In general, PPA can significantly improve the anti-UV aging performance of SBRMA. The Pearson correlations between the aging indexes of the macro and micro properties are also significant. In summary, PPA/SBRMA material is more suitable for high altitude cold regions than SBRMA, which provides a reference for selecting and designing asphalt pavement materials in high altitude cold regions. [ABSTRACT FROM AUTHOR]

The polyphosphoric acid (PPA) modified asphalt binder is a potential choice as one of the pavement materials for its excellent high-temperature performance and low cost. To further analyze the influences of temperature and load on the service life of pavement from the perspective of deformation behavior, six kinds of asphalt binders with different PPA dosages were prepared for Multiple Stress Creep and Recovery (MSCR) tests at five temperature levels. The deformation behavior is investigated by basic deformation parameters, rheological simulation, and energy parameter changes. The results show that the percent recovery (R) drops sharply while non-recoverable creep compliance ( J n r) goes up slightly with the increase in temperature. Three-element model, composed by E 1 , η 1 , and η 2 , can be used to describe the creep behavior. PPA-modified asphalt binder exhibits nonlinear creep behavior, and the logarithmic model can simulate recovery behavior better than the power–law model. Stored energy and dissipated energy can characterize the change of energy in the creep process under different conditions and show a significant correlation to deformation parameters. It is concluded that the elastic component of asphalt binders is increased by PPA, which is beneficial to the improvement of the deformation resistance and recovery capacity of asphalt binders. The recommended dosage of PPA is 1.5%. This investigation is conducive to a better understanding of the deformation behavior of PPA-modified asphalt binders and provides a reference for its engineering applications. [ABSTRACT FROM AUTHOR]

Garnet‐based solid‐state Li‐metal batteries (GSSBs) have the merits of high energy density and high safety. However, the realization of a stable and well‐matched Li|garnet interface for GSSBs remains challenging due to electron leakage and lithiophobic Li2CO3 impurity. To address these issues, herein, new surface chemistry is reported that converts the undesired Li2CO3 contaminant into an ultra‐thin lithium polyphosphate (Li‐PPA) layer through anhydrous polyphosphoric acid ‐induced in situ substitution reaction without damaging the water‐sensitive garnet electrolyte. In particular, the Li‐PPA interlayer not only facilitates the homogenous spreading of molten Li but also creates a robust electron‐blocking shield to suppress Li dendrite formation. As a result, the assembled Li symmetric cell exhibits a low interfacial impedance (4 Ω cm2) and high critical current density (1.8 mA cm−2) at 25 °C, which enables the cell to continuously cycle over 2500 h at 0.2 mA cm−2. Furthermore, the GSSBs paired with LiFePO4 deliver a high capacity of 149.3 mAh g−1 at 1 C and maintain 92.3% of the initial capacity after 500 cycles and can be used for solar energy storage, suggesting the feasibility of this interfacial engineering strategy for GSSBs. [ABSTRACT FROM AUTHOR]

Premature failure of road pavement due to oxidative aging of bitumen is a problem affecting the durability of bitumen in pavement. Therefore, this study investigates the morphologies (microstructures) of polymer-modified Agbabu Natural Bitumen (ANB) samples as well as the effects of aging on its chemical compositions and physical properties. The raw ANB sample was purified by moisture extraction and subsequent removal of impurities to form the base. The base was modified with High Density Polyethylene (HDPE), Polyethylene-vinyl-acetate (PEVA), Polystyrene-co-butadiene (PSCB) and Polyphosphoric acid (PPA) in percentage compositions of 2, 4, and 6wt.% using melt blend technique. Pressure Scanning Electron Microscopy (PSEM) was used to investigate the morphological changes. For long-term aging, base and 6wt.% polymer modified base samples at 60 °C were used to study its effects on chemical and physical compositions of samples. PSEM analysis showed that all the polymer have good compatibilities with the base bitumen at various percentage compositions. However, PSCB showed compatibility only at 2wt.%. Thermal aging generally reduced penetration values and increased the softening points of the base and modified base samples. In addition, its effects on chemical composition of base and 6wt.% modified base samples were found to be faster in the base sample compared to the modified base samples at various aging periods. Thus, the use of PEVA, HDPE and PPA for modification at the three percentage compositions is recommended. However, for PSCB, it is recommended only at 2wt.% due to poor compatibilities at 4 and 6wt.%. [ABSTRACT FROM AUTHOR]

Hydrogen-bonding catalytic reactions have gained great interest. Herein, a hydrogen-bond-assisted three-component tandem reaction for the efficient synthesis of N-alkyl-4-quinolones is described. This novel strategy features the first proof of polyphosphate ester (PPE) as a dual hydrogen-bonding catalyst and the use of readily available starting materials for the preparation of N-alkyl-4-quinolones. The method provides a diversity of N-alkyl-4-quinolones in moderate to good yields. The compound 4h demonstrated good neuroprotective activity against N-methyl-ᴅ-aspartate (NMDA)-induced excitotoxicity in PC12 cells. [ABSTRACT FROM AUTHOR]

With the aim of finding efficient initiators for electrophilic cyclizations of 2‐(3‐butenyl)quinazolin‐4(3H)‐ones, their reactions with a number of acids (НCl, CF3COOH, H2SO4, polyphosphoric acid, CF3SO2OH) and halogenating agents (I2, Br2, NIS, NBS) have been studied. As established, CF3SO2OH can be successfully applied in the synthesis of linear 1‐methyl‐2,3‐dihydropyrrolo[2,1‐b]quinazolin‐9(1H)‐ones while the use of I2, NIS, or NBS readily leads to angular 1‐(halomethyl)‐2,3‐dihydropyrrolo[1,2‐a]quinazolin‐5(1H)‐ones. [ABSTRACT FROM AUTHOR]

Rutting is the most common distress that most Iraqi asphalt pavements suffer from it. Asphalt binders are modified by using additives and polymers to enhance their physical qualities and fulfill the performance demands. Polyphosphoric acid (PPA) has been used in many countries to enhance the physical and mechanical characteristics of asphalt binders and mixtures that can improve the performance of asphalt pavements. In this paper, evaluation of the Iraqi asphalt binder and mixtures performance by using three percentages of Polyphosphoric acid (PPA) (0.4, 0.8, and 1.2) percent by asphalt binder weight and added to (60-70) penetration grade asphalt binder to show the applicability and suitability of using PPA in asphalt pavement in Iraq. Original asphalt binder and modified are subjected to traditional tests which are penetration, ductility, softening point, and viscosity. Results show better performance and enhancement of the physical properties of the modified binder. Other tests are Marshall Stability and wheel track tests. The results of the addition of PPA to the asphalt mixture show increases in the Marshall Stability and enhance the performance of the asphalt pavement mixtures. The wheel track test is applied to the original and modified mixture at two test temperatures 40 ?C and 50 ?C and the results show a decrease in the rut depth when the percentages of PPA increase. It is concluded that %PPA addition will enhance the performance of the Iraqi asphalt pavement and the mixture will be more rutting resistant, especially in high-temperature weather.

This paper represents a convenient method for the synthesis of N-[1-(2-acetyl-4,5-dimethoxyphenyl)propan-2-yl]benzamide and its Cu(II) complex. In silico analysis predicted spasmolytic activity for the compound. Based on the in silico calculations, the importance of the predicted ketoamide, and our previous experiments, we synthesized the ketoamide via ortho-acylation of N-[1-(3,4-dimethoxyphenyl)propan-2-yl]benzamide with acetic anhydride in polyphosphoric acid. We applied the title ketoamide in reaction with Cu(II) varying the solvents. We found that the reaction leads to the formation of a coordination compound when the ligand dissolved in DMSO reacts with a water solution of CuCl2 in an alkaline environment in a molar ratio M : L : OH– = 1 : 2 : 2. The structures of the new compounds are discussed based on their melting points, IR, 1H, 13C NMR and Raman spectral data. [ABSTRACT FROM AUTHOR]