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Gold-catalyzed difunctionalizations of o-alkynylbenzenesulfonamides with aryldiazonium salts are reported herein. Upon irradiation with the blue LEDs, benzosultam products were formed via aminoarylation accompanied by the release of N2. Without irradiation, aryldiazonium salts were engaged as efficient electrophiles, facilitating electrophilic deaurations of the vinyl-Au(I) intermediates, followed by tautomerization to give the N-aryl-substituted α-imino (E)-hydrazones. The regioselectivities of 6-endo-dig and 5-exo-dig cyclizations were excellent.

In this work, we demonstrate that pure three-dimensional honeycomb-like porous carbons (3D-HPC) can be prepared by one-step simultaneous carbonization and activation of Ganoderma lucidum spores (GLS) with KOH active agent. Benefiting from the specific natural morphology of GLS and uniform activation process, the obtained 3D-HPC exhibits pure honeycomb-like hierarchical structures. The obtained 3D-HPC-900 shows the honeycomb-like structures and a high density of narrow mesopores, leading to a high accessible surface area. Combined with high specific surface area of 1995 m2 g−1 and oxygen/nitrogen doping, 3D-HPC-900 exhibits a high specific capacitance of 224 F g−1 at a current density of 0.25 A g−1, an ultrahigh capacitance retention of 75.9% even the current density increased by 80 times, and an excellent cycling stability with 100% capacitance retention after 50,000 cycles. More importantly, the maximum energy density can reach up to 75.7 W h kg−1 at the power density of 1750 W kg−1 in ionic liquid. Meanwhile, the experimental results clearly reveal the exclusive effects of mesopores on improving the rate performance in electrochemical capacitors. Therefore, the work provides a clear method on preparation of high-valued honeycomb-like structured carbon materials to enhance the rate capability of carbon-based electrochemical capacitors.

A synergistic inhibition study was carried out on an aluminium/copper galvanic coupling model in neutral aerated NaCl solution using scanning vibrating electrode technique (SVET). The approach allows the simulation of the local micro-galvanic cells of AA2024-T3 obtained from the potential difference between the intermetallic particles (IMPs) and the aluminium matrix. The inhibition effect of CeCl3 and 3-Amino-1,2,4-triazole-5-thiol (ATAT) was demonstrated by the reduction in the galvanic current density over Al and Cu surfaces. An improved inhibition from positive synergistic effect was revealed by the combination of the two inhibitors after 24 h of immersion, with the best inhibition recorded for Ce1.5ATAT3.5. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and time of flight secondary ion mass spectrometry (ToF-SIMS) were used to characterize the Ce- and ATAT-based complex film formed and to illustrate the mechanism of inhibition.

Haze (H) is not an accumulative property based on the addition of internal haze (H i) and surface haze (H s) parameters, though the relation (H s = H − H i) is widely accepted and used nowadays in research and development of plastic films. To evaluate the correct relation, the analytical relation between the total haze (H) and the haze of a single film (h i) in the film superposition model was firstly concluded, which is 1 − H is equal to the product of 1 − h i of every single film. This relation was validated by the experimental results using thin films of different kinds of polymers with different hazes. Based on this relation, the expression of surface haze was concluded. When the two surfaces of a film were the same, the haze of the single surface H s ¯ = 1 − ( 1 − H ) / ( 1 − H i ) . $\overline {{H_{\rm{s}}}} = 1 - \sqrt {(1 - H)/(1 - {H_{\rm{i}}})} .$ The mathematical relation between haze and thickness was also obtained.

Despite the widespread use of anilines, synthetic challenges to these targets still exist. Selectivity is often an issue, when using the traditional nitration-reduction sequence or more modern approaches, including arene C–H aminations catalyzed by transition metals, photosensitizers, or electrodes. Accordingly, there is still a need for general methods to rapidly, directly access specific isomers of substituted anilines. Here, we report a simple route towards the synthesis of such motifs starting from benzyl alcohols, which are converted to anilines by the use of arylsulfonyl hydroxylamines, via an aza-Hock rearrangement. Good to excellent yields are observed. The method is applicable to various benzyl alcohol surrogates (such as ethers, esters, and halides) as well as simple alkylarenes. Functionalizations of pharmaceutically relevant structures are feasible under the reaction conditions. Over ten amination reagents can be used, which facilitates the rapid assembly of a vast set of compounds., Syntheses of anilines occur through a variety of methods, most requiring transition metals or multiple steps. Here the authors disclose a protocol to form anilines from benzyl alcohols via an aza-Hock rearrangement that uses only a sulfonyl hydroxylamine and solvent.

This work provides a new and simple method to improve the performance of polyamide reverse osmosis membrane, including selectivity properties and antifouling ability. Herein, quaternary ammonium groups have been immobilized on polyamide membrane surface by grafting and self-polymerization reaction of epoxy group in 2,3-epoxypropyl trimethyl ammonium chloride with tris(dimethylaminomethyl)phenol as curing catalyst. The surface properties of the modified membrane, such as surface charge, hydrophilicity and roughness have been characterized in detail and compared with virgin PA membrane. This novel modification method mainly achieves three advances in terms of membrane performance and fabricating technique. On one hand, the positively charged quaternary ammonium group immobilized on membrane surface can prevent cationic surfactant absorbing to improve fouling-resistance, due to the electric repulsion effect. On the other hand, self-polymerization reaction based on epoxy group occurred on polyamide surface can fill up the aggregate pore or reduce the pore size in polyamide, resulting in the increase of salt rejection. More importantly, the membrane modification process is very simple and efficient, which adapts to fabricate RO membrane with high performance on industrial production line completely.

Objective: Pirarubicin (THP), one of the anthracycline anticancer drugs, is widely used in the treatment of various cancers, but its cardiotoxicity cannot be ignored. Schisandrin B (SchB) has the ability to upregulate cellular antioxidant defense mechanism and promote mitochondrial function and antioxidant status. However, it has not been reported whether it can resist THP-induced cardiotoxicity. The aim of this study was to investigate the effect of SchB on THP cardiotoxicity and its mechanism.Methods: The rat model of cardiotoxicity induced by THP was established, and SchB treatment was performed at the same time. The changes of ECG, cardiac coefficient, and echocardiogram were observed. The changes of myocardial tissue morphology were observed by H&E staining. Apoptosis was detected by TUNEL. The levels of LDH, BNP, CK-MB, cTnT, SOD, and MDA in serum were measured to observe the heart damage and oxidative stress state of rats. The expression of cleaved-caspase 9, pro/cleaved-caspase 3, Bcl-2/Bax, and cytosol and mitochondrial Cyt C and Bax was evaluated by western blot. H9c2 cardiomyocytes were cocultured with THP, SchB, and mPTP inhibitor CsA to detect the production of ROS and verify the above signaling pathways. The opening of mPTP and mitochondrial swelling were detected by mPTP kit and purified mitochondrial swelling kit.Results: After 8 weeks, a series of cardiotoxicity manifestations were observed in THP rats. These adverse effects can be effectively alleviated by SchB treatment. Further studies showed that SchB had strong antioxidant and antiapoptotic abilities in THP cardiotoxicity.Conclusion: SchB has an obvious protective effect on THP-induced cardiotoxicity. The mechanism may be closely related to the protection of mitochondrial function, inhibition of mPTP opening, and alleviation of oxidative stress and apoptosis of cardiomyocytes.

Pirarubicin (THP), one of the anthracycline anticancer drugs, is widely used in the treatment of various types of cancer, but its cardiotoxicity cannot be ignored. Canagliflozin, the first sodium‑glucose co‑transporter‑2 inhibitor approved by the USA FDA, has been shown to have a significant effect on cardiovascular damage caused by diabetes. However, it has not been reported whether it can resist THP‑induced cardiotoxicity. The aim of the present study was to investigate the effect of canagliflozin on THP‑induced cardiotoxicity and its mechanism. A rat model of cardiotoxicity induced by THP was established and canagliflozin treatment was performed at the same time. The changes of electrocardiography, cardiac coefficient and echocardiogram were observed. The levels of lactate dehydrogenase, brain natriuretic peptide, creatine kinase MB, cardiac troponin T, superoxide dismutase (SOD) and malondialdehyde were detected. The expression of SOD2, NADPH oxidase 2, pro/cleaved‑caspase‑ and Bcl‑2/Bax were evaluated by western blotting. The primary culture of cardiomyocytes was prepared to explore the effect in vitro. After eight weeks, a series of cardiotoxicity manifestations were observed in THP rats. However, canagliflozin treatment had no significant effect on the above adverse reactions. Similarly, further studies showed that canagliflozin had no significant effect on THP‑induced cardiomyocyte injury in vitro. The present study showed that there was no significant protective effect of canagliflozin on THP‑induced cardiotoxicity and cardiomyocyte injury.

Novel etched iron oxide mediated synthesis of 3D tremella-like mesoporous Fe/N co-doped graphene composite was investigated. Through a synergistic mediation of acid etched Fe2O3 particles and released Fe3+, the nanoflakes of graphene oxide were transformed to Fe-doped 3D tremella-like mesoporous structure in hydrothermal condition. With high temperature treatment using melamine as the nitrogen source, the novel 3D tremella-like mesoporous Fe/N co-doped graphene composite for platinum-free counter electrode of the sensitized solar cell was synthesized. The samples had good pore size distribution and large specific surface area, which could be considered as an advantage for the permeation of electrolyte and beneficial to reduce the mass transfer resistance and promote the charge transfer. Significantly, the formed Fe-NX species bonding on the surface of graphene had sturdy covalent structure with high catalytic activity, which contributed to the excellent electrochemical properties and counter-electrode performance of dye-sensitized solar cell. Consequently, the photoelectric conversion efficiency reached 6.52%, which exceeded 5.87% of Pt and 3.49% of reduced graphene oxide electrodes.

A new corrosion inhibitor, cerium malate, was synthesized. Its inhibiting behaviour on coupled Al2Cu-Al2CuMg-Al, Al2CuMg-Al and Al2Cu-Al was studied. Cerium malate is effective in corrosion inhibition of the three coupled systems. The inhibition mechanism of cerium malate on pitting corrosion of Al2CuMg and Al2Cu phases in AA 2024-T3 was analyzed by scanning vibrating electrode technique (SVET), atomic force microscopy (AFM) and scanning kelvin probe force microscopy (SKPFM). The results indicate that cerium malate has good inhibiting effect on AA 2024-T3.

The inhibition of AA2024-T3 corrosion by the synergistic combination of 3-Amino-1,2,4-triazole-5-thiol (ATAT) and cerium chloride in sodium chloride solution is assessed. Analysis of electrochemical impedance spectroscopy results show improved corrosion inhibition for the inhibitor combination by increased charge transfer resistance. Scanning vibrating electrode technique was utilized for corrosion current monitoring and quantification. X-ray photoelectron spectroscopy and time of flight secondary ion mass spectrometry were utilized to characterize the ATAT/Ce based film and to explain the mechanism of inhibition. The obtained results demonstrate a good potential of the inhibitor combination for improved suppression of corrosion processes.

Cerium malate (CeMal) was tested as a corrosion inhibitor for AA2024-T3 in this work. Corrosion inhibition on bare AA2024-T3 indicated that the inhibiting effect was a result of the synergistic effect of cerium cations and maleic anions. The corrosion of AA2024-T3 was stagnated by greatly reducing the corrosion current when CeMal was present in NaCl solutions. CeMal was adsorbed on the surface of AA2024-T3 forming a protective film in the initial stage. Then, cerium cations transformed to cerium oxide/hydroxides, precipitating on the cathode sites to inhibit the further corrosion. The electrochemical impedance spectra results of the sol–gel coatings proved that CeMal was an effective corrosion inhibitor in the sol–gel coatings to provide corrosion protection for AA2024-T3.

A series of thin-film composite membranes based on polyurea has been fabricated by interfacial polymerization with branched polyethyleneimine and piperazine in the aqueous phase, and multi-isocyanate in the organic phase on porous polyethersulfone support for extreme pH nanofiltration. It is found that 1,4-phenylene diisocyanate and toluene diisocyanate are more suitable to react with multi-amine to form the dense crosslinking layer, thereby achieving improved permeation and separation properties. By optimizing the ratio of polyethyleneimine to piperazine in the aqueous phase and 1,4-phenylene diisocyanate content in the organic phase, the best performance membrane with a MgSO4 rejection higher than 97.0% has been obtained. The surface properties of the polyurea-based membranes, such as surface charge, hydrophilicity, roughness, and morphology structure have been characterized in detail. After exposure to 20% (wt/v) HCl, 20% (wt/v) H2SO4, as well as 20% (wt/v) NaOH aqueous solution for one year, PEI-0.4/PDI-0.25 membrane can still retain MgSO4 rejection higher than 90% at neutral pH testing condition, with more than a two-fold increase of water flux, due to the swelling of the polyurea separation layer. The relationship between the molecular structure of polyurea and acid/alkali stability of membrane is also investigated. More importantly, the optimal polyurea-based nanofiltration membrane exhibits comparable acid/alkali stability to commercial MPS-34 membrane produced by Koch industries, displaying a broad field of application with good prospects.

Food safety has aroused increasing public concerns because it is closely related to human health. As a common pollutant, mercury ions (Hg2+) can cause an enormous menace to human health even at very low fouling level. Herein, we designed a three-dimensional reduced graphene oxide (rGO) doped by silver nanoparticles (Ag-rGO), which could be employed as an effective sensing interface to electrochemically detect Hg2+. By characterization with scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), we confirmed that the Ag-rGO composites had multiple fold structures. After incubation with Hg2+, an obvious electrochemical signal enhancement was observed, which could be applied to detect the low level of Hg2+. The sensor based on Ag-rGO exhibited a low detection limit of 0.0049 μg/L of Hg2+ due to its multiple folds structure providing a large electrochemical active area and facilitating the electron transfer. Significantly, this proposed sensor was successfully used to evaluate the amount of Hg2+ in fish and human blood samples with acceptable results. This sensing strategy showed excellent performance for Hg2+ detection in food and clinical-related systems, which is of great significance for safeguarding food safety and human health.

In this work, a new type of cerium oxide particles with a graded mesoporous structure (Hierarchically meso-mesoporous cerium oxide, HMCe) was prepared as both inhibitor and carrier for loading 2-MBI (2-mercaptobenzimidazole) inhibitor, which was encapsulated by Eudragit E100 (EE100, a kind of amino methacrylate copolymer) to construct smart containers with pH controlled-release properties. The smart containers were added to a water-borne epoxy coating to develop active anti-corrosion coating on mild steel. The corrosion inhibition effect of 2-MBI and mesoporous cerium oxide particles was evaluated. Furthermore, the release of 2-MBI from the smart containers in response to acidic corrosion solution was also investigated using UV–vis spectroscopy. Electrochemical impedance spectroscopy (EIS) and salt spray tests were employed to evaluate the barrier properties and the active anti-corrosion performance of the coatings. The results showed that coating with newly designed smart containers has better anti-corrosion performance than coating with cerium oxide particles or 2-MBI alone. This work provides a new way to fabricate containers and actively protective coatings.

The solubility of terbinafine hydrochloride in four pure solvents, including methanol, ethanol, n -propanol and ethyl acetate and their binary solvent mixtures, including (methanol + ethyl acetate), (ethanol + ethyl acetate) and ( n -propanol + ethyl acetate) performed at different mass fractions of methanol, ethanol or n -propanol ranging from 0.1 to 0.9, was determined by using isothermal saturation method with temperatures ranging from (278.15 to 313.15) K. The descending order of the mole fraction solubility in pure solvents was as follow: methanol > ethanol > n -propanol > ethyl acetate, and for the three mixture with given initial composition, the solubility of terbinafine hydrochloride increased with increasing temperature and mass fraction of alcohol for the three systems including (methanol + ethyl acetate), (ethanol + ethyl acetate) and ( n -propanol + ethyl acetate). At the same mass fraction of methanol, ethanol or n -propanol and temperature, the solubility of terbinafine hydrochloride was greater in (methanol + ethyl acetate) than in the other mixed solvents. The maximum mole fraction solubility of terbinafine hydrochloride was observed in methanol (6.297 × 10 − 2 at 313.15 K), followed by that in ethanol (3.785 × 10 − 2 at 313.15 K), n- propanol (3.007 × 10 − 2 at 313.15 K) and ethyl acetate (1.497 × 10 − 2 at 313.15 K)·The obtained solubility data were correlated with Jouyban-Acree model, van't Hoff-Jouyban-Acree model, modified Apelblat-Jouyban-Acree model and CNIBS/R-K model. The correlation showed good agreement with experimental results, the largest values of relative average deviations ( RAD ) and the root-mean-square deviations ( RMSD ) between the experimental and calculated solubility were 4.32 × 10 − 2 and 15.28 × 10 − 4 , respectively. On the basis of the obtained solubility, the standard enthalpy of solution ( ΔH sol o ), the standard Gibbs energy ( ΔG sol o ) of solution and the standard entropy of solution ( ΔS sol o ) of terbinafine hydrochloride dissolved in pure and mixed solvents were obtained by the famous van't Hoff calculations. Thermodynamic treatment of solubility data of terbinafine hydrochloride in these pure and mixed solvents by “Apparent thermodynamic analysis” indicated that the dissolution is an endothermic and entropy-driven process. The experimental solubility and the models in this study could be helpful in purifying the crude terbinafine hydrochloride.

Sulfonated polyvinyl alcohol (SPVA) was synthesized by esterification reaction of PVA and sulfuric acid, and the structure was characterized by FTIR spectrum. Then a series of TFC membranes modified with cross-linked SPVA layer were fabricated by coating method, with glutaraldehyde as the cross-linker. The resulting TFC membranes were characterized by SEM, AFM, ATR-FTIR, XPS, streaming potential as well as static contact angle. The TFC membranes modified with SPVA exhibit decreased water flux and increased NaCl rejection with SPVA content increasing in the coating aqueous solution. The optimal PA-SPVA-0.5 sample exhibits a NaCl rejection of 99.18%, which is higher than the 98.32% of the virgin PA membrane. More importantly, the PA-SPVA-0.5 membrane shows much more improved fouling resistance to BSA and CTAB than virgin PA membrane and the TFC sample modified with PVA (PA-PVA-0.5). PA-SPVA-0.5 membrane loses about 8% of the initial flux after BSA fouling for 12 h, which is much lower than those of virgin PA and PA-PVA-0.5 membranes (28% and 15%, respectively). Furthermore, the flux recovery of the PA-SPVA-0.5 membrane reaches above 95% after cleaning. Thus, the PA-SPVA-0.5 membrane shows potential applications as antifouling RO membrane for desalination and purification.

In the present work, the sub-micrometer containers were prepared using mesoporous silica particles (SBA-15) with parallel channels as reservoir and 8-hydroxyquinoline as corrosion inhibitor. Layer-by-layer assembling was used to construct a shell of polyelectrolytes around the silica particles. Release of 8-hydroxyquinoline from sub-micrometer containers was studied in response to acidic or alkaline pH values. The results of electrochemical impedance spectroscopy (EIS) show the improvement of corrosion resistance of epoxy coatings containing sub-micrometer containers. Self-healing ability of the epoxy coatings was provided by sub-micrometer containers, as evidenced by the results of scanning vibrating electrode technique (SVET).

Raw coal is burned in furnaces or chain grate boilers. In this work, we studied the chamber combustion mechanism in a chain grate boiler (CGB) with a capacity of 20 t/hr. A mathematical model was built using Computational Fluid Dynamics (CFD). It was found that chamber combustion with swirl burners instead of grate firing has a positive effect on NO emissions. NO emissions dropped from 700 ppm in case 5 to 250 ppm in case 1. The calculated and measured NO emissions agreed well, with a discrepancy of less than 15%, except on plane 2 for four calculated cases. For the temperature field, the discrepancy between the measured and simulated values was below 12% for the four cases. These discrepancies between calculated and measured results are acceptable. This study provides a good idea for the design and reconstruction of CGBs. To reduce NO emissions, the reconstruction method can be used for CGBs instead of the grate firing system.

We have developed a facile and efficient Fe-catalyzed method for fabrication of porous carbons spheres with high graphitization degree (GNPCs) using glucose as carbon precursor at relatively low carbonization temperature. GNPCs not only have relatively large accessible ion surface area to accommodate greater capacity but also high graphitization degree to accelerate ion diffusion. As a typical application, we demonstrate that GNPCs exhibit excellent electrochemical performance for use in supercapacitors, with high specific capacity of 150.6 F g−1 at current density of 1 A g−1 and good rate capability and superior cycling stability over 10,000 cycles, confirming their potential application for energy storage. Moreover, it is believed that this method offers a new strategy for synthesis of porous carbons with high graphitization degree.

A new inhibitor pigment, cerium tartrate was studied as a pigment in epoxy coatings. The results of release measurements of Ce ions from epoxy coating in 0.05 mol/L NaCl indicate that cerium ions are able to transport through the epoxy coating, which is a key characteristic of inhibitor pigment. The electrochemical impedance spectroscopy (EIS) shows that cerium tartrate is an effective pigment for improving the barrier effect of epoxy coatings on AA2024-T3. The self-healing ability of cerium tartrate in artificial defects was verified by scanning vibrating electrode technique (SVET).

In this work, urea-formaldehyde (UF) microcapsules loaded with tung oil were prepared by in-situ polymerization. The mean diameter of the obtained microcapsules was 8.5 μm. The self-healing coating was prepared by the addition of 5 wt.% microcapsules into an epoxy matrix and then painted on the AA2024 substrate. The effect on the coating properties after the incorporation of microcapsules was investigated by adhesion tests and electrochemical impedance spectroscopy (EIS). It is found that 5 wt.% microcapsules in coating formulations did not impart a significant negative effect on coating properties. SEM and EIS tests were used to evaluate the self-healing effect. According to the fitting results of the EIS data on the scratched samples, the new film that formed by the polymerization of tung oil at the scratched area in the self-healing coating displays a resistance value of more than 106 Ω·cm2, which is much higher than 103 Ω·cm2 of the oxide layer in the neat epoxy coating. The neutral salt spray tests also confirm the good anti-corrosion performance of the self-healing coating.

Silica nanoparticles are used as additives to organic coatings to modify their properties. The interface of inorganic nanoparticles with an organic matrix can be a preferred location for accumulation of water. Surface treatment of nanoparticles with 3-glycidoxypropyltrimethylsilane (silane) is one way to reduce the water accumulation. In this work, using atomistic simulations (MD), we studied the effects of silane treatment on accumulation of water at the interface of nanoparticles. Three different epoxy phases and two methods of deposition of water were simulated. Water molecules were studied at two locations: (i) the interface of nanoparticles, and (ii) in the matrix of coatings. Additionally, the changes in the organic matrix due to surface treatment of nanoparticles were studied. The simulations show how silane treatment affects the interactions of water with nanoparticles in different epoxies, and also how silane treatment reduces the water accumulation in an organic matrix with nanoparticles.

The solubility of econazole nitrate (racemic mixture) in organic solvents is of clear importance for the design of separation processes and further theoretical studies. In this work, the solubilities of econazole nitrate in methanol, ethanol, n -butanol, isopropanol, ethyl acetate, 2-butanone, 3-methyl-1-butanol, acetonitrile, 1,4-dioxane, N , N -dimethylformamide (DMF), 1-methyl-2-pyrrolidinone (NMP) and acetone were determined at the temperatures from 278.15 K to 318.15 K under atmosphere pressure ( p = 101.2 kPa) by high-performance liquid chromatography (HPLC). It was found that the econazole nitrate solubilities in mole fraction in selected solvents increased with the increase in temperature. At a given temperature, they obeyed the following order from high to low in different solvents: NMP > DMF > methanol > 2-butanone > acetone > (3-methyl-1-butanol, ethanol) > acetonitrile > n -butanol > isopropanol > 1,4-dioxane > ethyl acetate. The experimental solubility data were correlated with the modified Apelblat equation and the Buchowski–Ksiązczak λh equation. The calculated solubilities using the modified Apelblat solubility model were in better agreement with the experimental values. The largest percentage of average relative deviation was 1.53% for solubility of econazole nitrate in isopropanol calculated with the λh equation, and the maximum value of root-mean-square deviation was 2.11 × 10 −4 . Based on the modified Apelblat equation, the apparent dissolution enthalpies of econazole nitrate in twelve pure solvent were derived. The results indicate that the dissolution of econazole nitrate in all studied cases is endothermic process.

The solubility of 2,4′-dihydroxydiphenyl sulfone in methanol, ethanol, acetone, acetonitrile, ethyl acetate, 1,4-dioxane, n-butanol, isopropanol and 2-butanone was determined at temperatures from (278.15 to 313.15) K under 101.2 kPa by using the high-performance liquid chromatography (HPLC). With the increase in temperature, the solubility of 2,4′-dihydroxydiphenyl sulfone in these solvents increased. Generally, the mass fraction solubility followed the sequence from high to low in different solvents except for 1,4-dioxane: acetone > methanol > (2-butanone, ethanol) > isopropanol > n-butanol > ethyl acetate > acetonitrile. The solubility of 2,4′-dihydroxydiphenyl sulfone in 1,4-dioxane showed the strongest positive dependency on temperature. The measured solubility of 2,4′-dihydroxydiphenyl sulfone were correlated by using four thermodynamic models, which corresponded to the modified Apelblat equation, λh equation, Wilson model and NRTL model. The largest values of RMSD and RAD were 9.52 × 10−4 and 1.54%, respectively. By comparing the four models, the computed solubility using the modified Apelblat equation provided better agreement with the experimental values than those using the other three models. On the whole, the four models were all acceptable for describing the solubility of 2,4′-dihydroxydiphenyl sulfone in the selected solvents. In addition, the standard molar dissolution enthalpy and excess enthalpy of solution of 2,4′-dihydroxydiphenyl sulfone in the solvents were evaluated. The dissolution process of 2,4′-dihydroxydiphenyl sulfone in the selected solvents was endothermic. The study on the solubility of 2,4′-dihydroxydiphenyl sulfone in the selected solvents and solution properties can provide fundamental data in the separating process of 2,4′-dihydroxydiphenyl sulfone from its isomeric mixtures.

In the present study, the solubility of 4,4′-dihydroxydiphenyl sulfone in mixed solvents of (acetone + methanol), (ethyl acetate + methanol), (acetonitrile + methanol), and (acetone + methanol) were determined experimentally by using the isothermal dissolution equilibrium method within the temperature range from (278.15 to 313.15) K under atmosphere pressure. The solubility increased with increasing temperature in the binary solvent mixtures at constant solvent composition. At constant temperature and solvent composition, the dissolving capacity of 4,4′-dihydroxydiphenyl sulfone in the four binary solvent mixtures ranked as (acetone + ethanol) > (acetone + methanol) > (ethyl acetate + methanol) > (acetonitrile + methanol). The obtained solubility data were correlated by employing the Jouyban–Acree model, modified Apelblat–Jouyban–Acree model, Ma model and Sun model. The four models were proven to give good representation of the experimental solubility data. The largest value of relative average deviations...

A new and convenient procedure is developed for the preparation of N-sulfonylbenzotriazoles from sodium sulfinates and benzotriazoles using molecular iodine as catalyst via the SN bond formation reaction. This catalytic radical sulfonylation proceeds efficiently in air at room temperature under neutral conditions, and in short reaction time, to afford the corresponding N-sulfonylbenzotriazoles in good yields, thus extending the catalytic application of molecular iodine in organic synthesis.

This article reported an eight steps formal total synthesis of (−)-kainic acid in 16% overall yield from an enantiopure starting material. The key transformations include an efficient tandem N-allylation/SN2′ reaction to construct the 2,3-trans-3,4-cis tri-substituted pyrrolidine and a HgCl2-promoted methanolysis of 1,4-benzodithia-fulvene to furnish the ester group.

The solubility of 3-chloro -N -phenylphthalimide in binary mixed solvents of (acetone + methanol, ethyl acetate + methanol and 1,4-dioxane + methanol) were determined experimentally by using the isothermal dissolution equilibrium method within the temperature range from (288.15 to 323.15) K under atmosphere pressure. For the binary systems of (acetone + methanol) and (1,4-dioxane + methanol), the solubility of 3-chloro -N -phenylphthalimide increased with increasing temperature and mass fraction of acetone or 1,4-dioxane; and for the (ethyl acetate + methanol) system, at a given composition of ethyl acetate, the solubility of 3-chloro -N -phenylphthalimide increased with an increase in temperature; nevertheless at the same temperature, they increased at first and then decreased with increasing mass fraction of 1,4-dioxane. At the same temperature and mass fraction of acetone, ethyl acetate or 1,4-dioxane, the solubility of 3-chloro -N -phenylphthalimide was greater in (1,4-dioxane + methanol) than in the other two mixed solvents. The solubility values were correlated by employing the Jouyban–Acree model, van’t Hoff–Jouyban–Acree model, Apelblat–Jouyban–Acree model, Ma model, and Sun model. On the whole, the Ma model and Sun model were proven to provide good representation of the experimental solubility results. Furthermore, the dissolution enthalpies of the dissolution process were calculated. The dissolution process of 3-chloro -N -phenylphthalimide in these mixed solvents is endothermic. The experimental solubility and the models in this study could be helpful in purifying 3-chloro- N -phenylphthalimide.

The solubilities of 1,5-dinitro-naphthalen in eight organic solvents (acetonitrile, ethanol, trichloromethane, 1-propanol, acetone, toluene, ethyl acetate and ethylbenzene) were determined experimentally by using a static equilibrium method at temperatures ranging from (273.15 to 313.15) K under atmosphere pressure (101.2 kPa). They all increased non-linearly with the increase in temperature for a certain solvent. Generally, the order of the solubility of 1,5-dinitro-naphthalen from high to low in different organic solvents was: trichloromethane > toluene > (ethyl acetate, acetone) > ethylbenzene > acetonitrile > 1-propanol > ethanol. The maximum solubility was 4.508 × 10− 3 in mole fraction. As the temperature decreased from 313 K to 273 K, the maximum solubility decreased from 4.508 × 10− 3 to 1.573 × 10− 4. The measured solubility data of 1,5-dinitro-naphthalen in the studied solvents were correlated with four solubility models, which corresponded to the modified Apelblat equation, λh equation, Wilson model and NRTL model. The calculated solubilities agreed better with the experimental values by using the modified Apelblat equation than the other three models. The relative average deviations obtained via the four models were all

In this work, we used atomistic level simulations to study water molecules confined between an epoxy layer and alumina substrate. Water is responsible for many complex reactions at the interface of substrate, which makes understanding characteristic properties of water at this particular confinement essential. Three different confinement sizes were selected. The substrate is hydroxylated gamma alumina and the organic coating layer is constructed with epoxy molecules. Different properties such as density, mobility and displacement, inter-molecular structures, power spectra, and hydrogen bond energy of water molecules were obtained. The results are studied in connection with the size of confinement. It is shown that the properties of water in this type of confinement are different from the bulk water and as the size of confinement decreases, some of the unique behaviors of water molecules are revealed.

Recrystallization behavior and the final crystallite orientation of biaxially oriented polyethylene (BOPE) film from different melted states have been studied by using differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD), respectively. WAXD result shows that two kinds of crystallites (1 and 2) with different orientations are aligned around the transverse direction (TD) of the film plane. When BOPE film is annealed in the temperature range of 110~125 °C, the residual crystallites 1 are still aligned along the TD, while the residual crystallites 2 are gradually rotated and aligned along the machine direction (MD). Recrystallization of BOPE film from the partially melted states is enhanced and the maximum crystallization peak shifts to higher temperature by 7 °C. The newly formed crystallites after recrystallization are aligned along the TD and MD, respectively. When annealing temperature attains to 128 °C, a trace amount of residual crystallites 1 persists along the TD. The newly formed crystallites after recrystallization are also aligned the TD. When the storing temperature range is in 130–150 °C, the melt memory effect occurs in BOPE film, and it influences crystallization kinetics and the crystallite orientation.

A convenient procedure is developed for the preparation of selenolactones from unsaturated acids and diselenides using a catalytic amount of ammonium iodide in combination with m-chloroperoxybenzoic acid as the oxidant. This catalytic ring-closing method proceeds efficiently at room temperature under neutral conditions, and in short reaction times, to afford the corresponding selenolactones in good yields. Using the same reaction conditions, cyclic selenoethers and tellurocyclization products are prepared, thus extending the catalytic application of inorganic iodides in organic synthesis.

KBr or NaCl is found to be a good catalyst in Se–Se bond cleavage of diselenides in the present of the oxidant mCPBA. The electrophilic addition of the in situ generated reactive electrophilic selenium species PhSeX (X = Br, Cl) to alkenes in AcOH provides a convenient access to 2-acetoxy-1-selenides. Compared with other catalysts, KBr or NaCl is less expensive and more environment-friendly.

The galvanic corrosion of the coupled Al2Cu and Al as well as Al3Fe and Al in 0.005 M NaCl in and without the presence of cerium cinnamate was studied. Scanning vibrating electrode technique and scanning ion-selective electrode technique were used to measure the distribution of current densities and pH. The results indicate that cerium cinnamate played inhibiting effect on the coupling corrosion of Al2Cu–Al and Al3Fe–Al. For Al2Cu–Al, the inhibition was mainly influenced by the production of cerium oxide/hydroxide on Al2Cu surface. However, for Al3Fe–Al, the inhibition was mainly influenced by the adsorbed cerium cinnamate on the Al3Fe surface.

In the presence of a catalytic amount of KI combined with oxidant H2O2, a convenient catalytic procedure has been developed for the direct preparation of arylselanyl anilines from N,N-disubstituted anilines and diselenides. In this protocol, KI is first oxidized by H2O2 into hypoiodous acid, which promotes the cleavage of Se–Se bond in diselenide. The in situ generated active electrophilic selenium species then reacts with N,N-disubstituted aniline, affording 4-arylselanyl aniline with high regioselectivity and good yield via an electrophilic substitution. This metal-free catalytic method is convenient in neutral condition at room temperature and in short time, not only arylselanyl anilines, but also alkaylselanyl anilines have been prepared, which extends the catalytic application of KI in organic synthesis.

A new corrosion inhibitor, cerium tartrate, was synthetized. The inhibition behavior of cerium tartrate for 2024-T3 aluminum alloy was investigated in 0.05 M NaCl solution. The immersion tests indicate that the corrosion of Al2CuMg phase was well inhibited. The electrochemical results show that both anodic and cathodic inhibitions are present during the corrosion process. The surface characterizations reveal that the protective film of cerium tartrate inhibits the dealloying of Al2CuMg phase in the initial stage, and then cerium ions transform to cerium oxide/hydroxides and appear at the Al2CuMg phase, blocking the further corrosion at those corrosion sites.

Microcapsules containing core materials are promising component for developing self-healing coatings. In the present work, urea-formaldehyde capsule containing core material with size of micrometer was prepared by in-situ encapsulation method. The morphology of the microcapsules was characterized by scanning electron microscopy. A corrosion inhibitor, benzotriazole, was successfully loaded on the outside of microcapsules by layer-by-layer assembling using polyelectrolytes. Thus, the modified microcapsules are promising to provide healing ability combined by release of interior core material and exterior corrosion inhibitor.

This work presents the silane-based sol–gel coatings that prepared by in situ doping 8-hydroxyquinoline as corrosion inhibitor for the protection of AA 2024-T3. The morphology and thickness of the sol–gel coatings were observed by scanning electron microscope (SEM). Immersion tests and electrochemical impedance spectroscopy (EIS) were used to study the corrosion resistance of the blank and 8-hydroxyquinoline doped sol–gel coatings. The results indicate that the addition of 8-hydroxyquinoline effectively improved the corrosion resistance of the sol–gel coatings. The self-healing effect of 8-hydroxyquinoline on the corrosion in the defects of sol–gel coating was assessed by scanning vibrating electrode technique (SVET) and proved by the results of energy-dispersive X-ray spectroscopy (EDS) mapping.

A series of thin-film composite nanofiltration membranes have been fabricated by coating the poly(vinyl alcohol) and 3-mercaptopropyltriethoxysilane aqueous solution prepared by a sol–gel process on porous polysulfone support, followed by thermal cross-linking treatment. In order to improve the hydrophilicity of the nanofiltration membranes, the –SH in the membranes are oxidized into –SO 3 H by immersing the membranes in H 2 O 2 aqueous solution. Notably, no organic solvent is used during the membrane preparation, showing enough green chemistry technology for environmental protection. The properties of the composite nanofiltration membranes are characterized by ATR-FTIR, SEM, AFM and static contact angle. The optimal composite nanofiltration membrane (PVA-SMPTES-0.6) developed exhibits a rejection of 98.0% and a water flux of 43.3 L m −2 h −1 for a feed containing 2000 mg L −1 Na 2 SO 4 at 2.0 MPa. Furthermore, no irreversible changes in membrane performance have been observed after prolonged exposure (up to 30 days) of PVA-SMPTES-0.6 membrane to extreme acid or alkali aqueous solution.

With KI as catalyst and m-chloroperbenzoic acid as the oxidant in acetic acid, a novel and efficient catalytic procedure has been developed for acetoxyselenenylation of alkenes, which providing a series of 2-acetoxy-1-selenenylation compounds with high regioselectivity and good yields in mild conditions. In this protocol, KI is first oxidized by m-chloroperbenzoic acid into acetylhypoiodite, which rapidly reacts with diselenide to form the active electrophilic selenenylating reagent, following an electrophilic addition of alkenes and 2-acetoxy-1-selenenylation compounds are obtained. The suitable equivalent ratio of alkene to diselenide is 1.2.

The molecular dynamics (MD) method can be a reliable tool for studying of organic coating/metallic substrate systems, however its accuracy is limited to the force field governing the dynamics of systems. These systems can be divided into three parts: (i) organic phase, (ii) substrate, (iii) interface between the organic phase and substrate. In this work, three recent ReaxFF descriptions were selected. A set of complex experimental data and density functional calculations was selected as the reference point. The density and structural analysis of a wide range of crystalline organic compounds were studied. The density, structural analysis, and self-diffusion constant of water at room temperature were obtained. The glass transition temperature of three different cross-linked epoxy were obtained and compared with the reported experimental results. The interaction energies of different configurations of epoxy and water over an alumina substrate were studied. Additionally, the reaction of water with aluminum was studied. The accuracy of these ReaxFF descriptions in reproducing the reference data was assessed. The results show there is a single ReaxFF description for accurate simulation of C/H/N/O/Al systems, which enables atomistic simulations of complex epoxy coatings/aluminum substrates systems.

New insights on the effect of nature and number of polyelectrolyte (PE) shells on active anticorrosion potential of microcontainers (MCs) applied as pH-sensitive reservoirs in coatings for the protection of AA2024-T3 is reported. Mesoporous silica particles (MSP) were loaded with benzotriazole (BTA) and shelled with different polyelectrolyte multilayers (PEM), demonstrating pH sensitivity. Weak-weak polyelectrolyte (W-W PE) shells allow immediate release of inhibitor, but weak-strong polyelectrolyte (W-S PE) shells encourage slower, more controlled and prolonged release, as revealed by release profiles of BTA from microcontainers. Active anticorrosion protection characterizations of the coatings doped with microcontainers were carried out by electrochemical techniques (EIS, SVET) and salt spray tests. Results reveal dependence of active properties of coatings on the nature and number of polyelectrolyte multilayers of microcontainers. We anticipate that proper choice of PEMs on smart containers can aid controlled functionalization of active feedback systems.

The coupling of pure Al, Cu and Mg wires and the coupling of Al 2 CuMg intermetallic rod and Al wire were used to study the corrosion process of Al 2 CuMg phase particles in 2024-T3 aluminium alloy, by means of scanning vibrating electrode technique (SVET) and scanning ion-selective electrode technique (SIET). The results show the preferential dissolution of Mg in the coupling of Al, Cu and Mg. Al 2 CuMg was found to show self-dissolution when coupled with Al, rather than anodic dissolution. According to the results, a mechanism of early corrosion of S phase in AA2024-T3 is proposed.

A new method for the synthesis of γ-glutamylmethylamide is presented. Glutamic acid γ-methyl ester was used as substrate for γ-glutamylmethylamide synthesis catalyzed by Escherichia coli with γ-glutamyltranspeptidase activity. Reaction conditions were optimized by using 300 mM glutamic acid γ-methyl ester and 3,000 mM methylamine at pH 10 and 40 °C. Bioconversion rate of γ-glutamylmethylamide reached 87 % after 10 h. γ-Glutamyltranspeptidase was reversibly inhibited only when glutamic acid γ-methyl ester was above 300 mM.

Using organic coatings with high barrier property in combination with active corrosion protection can improve corrosion protection of aluminum alloys. In this work, 3-Amino-1,2,4-triazole-5-thiol (ATAT) was used as organic inhibitor in developing anticorrosion coatings for AA2024-T3. The delivery of ATAT was achieved by using smart microcontainers with ATAT that respond to pH change caused by corrosion reaction at the coating-substrate interface. The developed coatings with low concentration of smart microcontainers showed a slight reduction of barrier properties, but gained active corrosion protection capability. The resistance of the coatings reduced the rate of penetration of corrosive species and the active corrosion protection stopped the damaging reactions at the coating-substrate interface. The active corrosion protection is also evident in the case of coatings with mechanical damages, when the barrier property of coatings is compromised. Waterborne coatings with smart microcontainers for delivery of ATAT exhibited enhanced performance for corrosion protection of AA2024-T3.