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Recycling of valuable solutes and recovery of organic solvents via organic solvent nanofiltration (OSN) are important for sustainable development. However, the trade-off between solvent permeability and solute rejection hampers the application of OSN membranes. To address this issue, the poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) nanoparticle membrane with hierarchical pores is constructed for OSN via vacuum filtration. The small pores (the free volume of the polymer chain) charge for the solute rejection (high rejection efficiency for low molecule weight solute) and allow solvent passing while the large pores (the void between two PEDOT:PSS nanoparticles) promote the solvent transport. Owing to the lack of connectivity among the large pores, the fabricated PEDOT:PSS nanoparticle membrane enhanced solvent permeance while maintaining a high solute rejection efficiency. The optimized PEDOT:PSS membrane affords a MeOH permeance of 7.2 L m -2 h -1 bar -1 with over 90% rejection of organic dyes, food additives, and photocatalysts. Moreover, the rigidity of PEDOT endows the membrane with distinctive stability under high-pressure conditions. The membrane is used to recycle the valuable catalysts in a methanol solution for 150 h, maintaining good separation performance. Considering its high separation performance and stability, the proposed PEDOT:PSS membrane has great potential for industrial applications., (© 2024 Wiley‐VCH GmbH.)

Addressing climate change requires transitioning to cleaner energy sources and adopting advanced CO 2 capture techniques. Clay minerals are effective in CO 2 adsorption due to their regenerative properties. Recent advancements in nanotechnology further improve their efficiency and potential for use in carbon capture and storage. This study examines the CO 2 adsorption properties of montmorillonite and saponite, which are subjected to a novel microwave-assisted acid treatment to enhance their adsorption capacity. While montmorillonite shows minimal changes, saponite undergoes significant alterations. Furthermore, the addition of silica pillars to smectites results in a new nanomaterial with a higher surface area (653 m 2 g -1 ), denoted as reversed smectite, with enhanced CO 2 adsorption capabilities, potentially useful for electrochemical devices for converting captured CO 2 into value-added products.

Despite good compatibility with Li metal, garnet solid electrolytes suffer from severe electron-attack-induced Li-metal penetration and large interfacial resistance. Here, a formic acid (HCOOH)-induced electron-blocking and lithiophilic interlayer is created via a spontaneous reaction with surface Li 2 CO 3 contamination on the garnet electrolyte (LLZTO) pellet. Unlike previous methods that involved immersing LLZTO in acidic solutions, this study employs a volatile small-molecule organic acid that is easily removable, condensed, and recyclable, thus circumventing the environmental drawbacks associated with acid waste. The Li symmetric cell assembled with HCOOH-treated LLZTO exhibits a low interfacial impedance (3 Ω cm 2 ) and a high critical current density (1.7 mA cm -2 ) at room temperature, enabling the cell to cycle continuously for over 1000 h at 0.2 mA cm -2 . Furthermore, under a stacking pressure of 2 MPa, stable lithium plating/stripping was achieved at a current density of 0.3 mA cm -2 with the assistance of HCOOH treatment. Additionally, the battery paired with a LiFePO 4 cathode delivers a high capacity of 151.7 mAh g -1 at 1 C and maintains 88.5% of the initial capacity after 500 cycles, suggesting the feasibility of this interfacial engineering strategy for garnet-based solid Li-metal batteries.

In this work, the effect of microwave-assisted acid treatments on the morphological and crystallochemical characteristics of chrysotile fibers is investigated. A low concentration of nitric acid (0.2 N) is used to remove Mg 2+ -species located in the octahedral sheet of its structure, thereby causing a crystallo-chemical change forming a skeleton of non-crystalline amorphous silica. This skeleton maintains an elongated morphology but characterized by rounded -not sharp-edges and porous surfaces whose physical resistance under stress is reduced when compared with the initial fibers of chrysotile, favoring a lower pathogenicity of the fibers. Thus, microwave-assisted acid treatment rise as a low-cost, fast and effective option in avoiding the dangerousness associated with asbestos waste management., (© 2024. The Author(s).)

The Si/Al molar ratio of MAZ aluminosilicate zeolite prepared by the direct hydrothermal method is generally less than five, thus giving rise to poor thermal and hydrothermal stability for this low-silica zeolite. With the purpose of enhancing the Si/Al molar ratio of MAZ zeolite, post-synthesized methods including acetic acid treatment and steaming treatment, as well as interzeolite transformation from FAU zeolite, were employed to prepare MAZ zeolite with high silica. It was found that steaming treatment was more effective in increasing the Si/Al molar ratio in comparison with acetic acid treatment, affording a maximum Si/Al molar ratio of 16.9 along with a preserved crystallinity of approximately 75%. Additionally, high-silica MAZ zeolite with a Si/Al molar ratio of up to 7.3 was also capable of being directly hydrothermally synthesized using interzeolite transformation from FAU zeolite.

Modifying starch allows for improvements in its properties to enable improved uses in food matrices, bioplastics, and encapsulating agents. In this research, four varieties of native potato starch were modified by acid treatment, enzymatic treatment, and ethanol precipitation, and their physicochemical, structural, thermal, and techno-functional characteristics were analyzed. According to FT-IR analysis, no influence of the modified starches on the chemical groups was observed, and by scanning electron microscopy (SEM), spherical and oval shapes were observed in the acid and enzymatic treatments, with particle sizes between 27 and 36 μm. In particular, the ethanolic precipitation treatment yielded a different morphology with a particle size between 10.9 and 476.3 nm, resulting in a significant decrease in gelatinization temperature (DSC) and more pronounced crystallites (XRD). On the other hand, the enzymatic treatment showed higher values for z-potential (ζ), and the acid treatment showed lower mass loss (TGA). Acid and ethanolic treatments affected the dough properties compared to native starches. The techno-functional properties showed a decrease in the water absorption index, an increase in the water solubility index, and varied swelling power behaviors. In conclusion, the modification of potato starches through acid, enzymatic, and ethanolic precipitation treatments alters their physicochemical properties, such as swelling capacity, viscosity, and thermal stability. This in turn affects their molecular structure, modifying morphology and the ability to form gels, which expands their applications in the food industry to improve textures, stabilize emulsions, and thicken products. Furthermore, these modifications also open new opportunities for the development of bioplastics by improving the biodegradability and mechanical properties of starch-based plastic materials.

The hemicellulosic fraction of lignocellulosic biomass is a very important material, due to the significant concentration of pentoses present in its composition and that can be used sustainably in biotechnological processes such as the production of fumaric acid. Research efforts are currently being promoted for the proper disposal and valorization of empty fruit bunches (EFB) from oil palm. In this work, seventeen Rhizopus species were evaluated in a fermentation medium with EFB hydrolyzate, without detoxification, as a carbon source for fumaric acid production. Rhizopus circicans 1475 and Rhizopus 3271 achieved productions of 5.65 g.L -1 and 5.25 g.L -1 of fumaric acid at 30 °C, 120 rpm for 96 h, respectively. The percentage of consumed sugars, mainly pentoses, was 24.88% and 34.02% for R. circicans 1475 and R 3271, respectively. Soy peptone and ammonium sulfate were evaluated as nitrogen sources, where soy peptone stimulated the formation of biomass pellets while ammonium sulfate produced mycelia and clamps., (© 2024. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.)

Light-driven water splitting has gained increasing attention as an eco-friendly method for hydrogen production. There is a pressing need to enhance the performance of catalysts for the commercial viability of this reaction. Many methods have been proposed to improve catalyst performance; however, an economical and straightforward approach remains a priority. This paper presents an uncomplicated technique called acid treatment, which augments the catalytic performance of nanoparticles. The method promotes a change in the catalytic reactivity by causing a deficit in electron density of Ti and O on the surface of TiO 2 nanoparticles without altering their size, morphology, or crystal structure. In the Eosin Y sensitized photocatalytic hydrogen production system, nitric acid treated TiO 2 (16.95 μmol/g) exhibited 1.5 times the hydrogen production compared to bare TiO 2 (11.15 μmol/g)., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Ltd.)

To develop an effective method to eliminate green macroalgae attached to Neopyropia aquaculture nets, we explored the influence of mixed acid solution on the photosynthetic fluorescence characteristics of Ulva spp. (green macroalgae) and Neopyropia yezoensis (red macroalgae) from Dafeng and Rudong aquaculture areas in Jiangsu Province, China. Treatment with mixed acid solution (0.0475 % hydrochloric acid:citric acid (pH 2.0) at a ratio of 4:3) for 60 s caused death of Ulva spp., but did not affect N. yezoensis. Additionally, a mixed acid solution effectively eliminated green macroalgae from Neopyropia aquaculture rafts and the marine environment remained unaffected. Hence, the application of mixed acid solution treatment has demonstrated significant efficacy in eradicating green macroalgae adhered to Neopyropia aquaculture rafts, thus presenting a promising strategy for mitigating green macroalgae proliferation in Neopyropia aquaculture areas and curbing their contribution to green tides., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Arsenic-containing sludge (ABG) is a common hazardous waste in the metallurgical industry and poses a serious threat to environmental safety. However, its instability and mobility have a significant impact on the environment. Traditional curing methods are time-consuming and costly, often resulting in incomplete curing. In this study, we introduce a curing/stabilisation method with a steel slag-fly ash gel material after ABG acid treatment. The toxic leaching of arsenic from ABG was reduced to 220 mg/kg by treating the sludge with acids (H 2 SO 4 -H 3 PO 4 ) at different solid-to-liquid ratios. Afterward, H 2 O 2 was added to oxidise As(III) to As(V). The ABG was cured/stabilised using an alkali-activated steel slag-fly ash gel material. The cured product exhibited optimal arsenic fixation under an ABG/steel slag/fly ash mass ratio of 1:4:2, a curing temperature of 60°C, a curing time of 20 h, and an ambient pH of 12.5. Under these conditions, steel slag-fly ash facilitated Ca-As precipitation, resulting in a hydration reaction that produced C-S-H gel. Additionally, the reaction generated calcium hydroxide, calcium and iron pyroxene, silica, and iron ferrite, which adsorbed part of the free arsenic, completing the curing of the acid-treated ABG and stabilising arsenic leaching toxicity. The leaching of arsenic in the ABG was much lower than the Chinese 'Hazardous Wastes Leaching Toxicity Identification Standard' (GB5085.3-2007) (5 mg/L), with an arsenic curing rate exceeding 99%. The mechanism of arsenic solidification involves the combined effects of chemical precipitation, physical encapsulation, and adsorption. Collectively, our findings demonstrated that the use of steel slag-fly ash gel as a functional material for ABG curing holds considerable environmental and economic benefits. Therefore, this study provides theoretical guidance and provides insights into the experimental feasibility of ABG treatment.

The jarosite waste used during this study consists of minute amount of arsenic that has a potential to be leached into environment when kept in open area. This study tried to recover arsenic from jarosite waste using hydrometallurgical treatment. The comprehensive characterization of jarosite samples was performed using various analytical techniques, including X-ray diffraction (XRD), Fourier transform Infrared (FTIR), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX), and it was characterized as natrojarosite. For optimal removal of arsenic, the response surface methodology (RSM) was applied with the key factors, including dosage (A), time (B), temperature (C), and acid concentration (D) on the recovery of arsenic. The results indicated that the dosage (A) and acid concentration (D) demonstrated significant positive effects on arsenic recovery. As expected, the higher dosage and acid concentration was associated with increased recovery percentages for the arsenic from jarosite. Whereas time (B) and temperature (C) did not exhibit statistically significant recovery of arsenic within the specified experimental range. The contour plots showed the optimal operating conditions for the highest recovery percentage was approximately 52.61% when 2.5 g of jarosite was treated with 10 mol/L acid for 150 min at operating temperature of 80°. Although our study showed very moderate recovery of arsenic, it is first report where arsenic has been removed from jarosite waste. Readjustment of range of operating parameters would provide more insight into the further optimization of the yield., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Objectives: Utilizing Ti and Ti alloys as dental materials established a huge spurt in the field of dentistry. Since implantation is an invasive procedure that involves tissue penetration, infection control is mandatory for increasing the success rate of the implant treatment. In this study, we aimed to assess the impact of the surface physicochemical properties of acid-treated Ti on microorganisms specifically bacteria., Methods: After investigating the surface morphology and characteristics of acid-treated and untreated Ti sheets, we evaluated their potential to capture Escherichia coli (E. coli.) as well as the latter's survival on the surface of both types of sheets. Finally, we assessed the efficiency of the antibacterial properties exhibited by Ti against the oral microflora., Results: SEM images revealed surface roughening of the acid-treated Ti represented by significantly irregular shape. Moreover, the acid-treated Ti exhibited remarkable hydrophobicity. A quantitative evaluation confirmed that acid-treated Ti has higher bacterial capture and antibacterial properties than untreated Ti. Further experiments showed similar effects of both types of Ti not only on E. coli but also on oral microflora., Significance: Results suggest that acid treatment of Ti surface is a potent technique for enhancing the antibacterial properties of Ti-derived materials., (Copyright © 2023. Published by Elsevier Inc.)

Hydrochars are promising adsorbents in pollutant removal for water treatment. Herein, hydrochloric acid (HCl) co-hydrothermally treated hydrochars were prepared from rice husk biomass at 180 °C via a one-step hydrothermal method. Adsorption behaviors of levofloxacin (LVX) on hydrochars were evaluated. The specific surface area and pore volume of the hydrochar synthesized in 5 mol/L HCl (5H-HC) were almost 17 and 8 times of untreated hydrochar, respectively. The 5H-HC sample exhibited the highest LVX adsorption capability at room temperature (107 mg/g). Thermodynamic experimental results revealed that adsorption was a spontaneous endothermic process. Yan model provided the best description of the breakthrough behavior of LVX in bioretention column, indicating that the adsorption on the samples involved several rate-limiting factors including diffusion and mass transfer. The results show that facile HCl co-hydrothermal carbonization of waste biomass can produce novel hydrochars with high LVX adsorption ability., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Acid treatment can increase the sludge calorific value to some extent by separating inorganic elements. In order to determine the mechanism by which acidification affects the sludge calorific value from an organic perspective, we investigated the changes in organic matter and dewaterability under different pH conditions. The results of this study showed that acidification conditioning retained organic matter while removing a greater amount of inorganic elements. Furthermore, acid treatment significantly increased the zeta potential and particle size of sludge particles and facilitated the precipitation of biological organic components from the supernatant to the surface of sludge particles. Acid-treated sludge exhibited a lower moisture content and a higher proportion of organic matter, and sludge treated with H 2 SO 4 , HCl, and HNO 3 exhibited respective increases in calorific values of 12.14%, 7.92%, and 8.01% under pH 2. The calorific value of the acid-treated sludge was higher, making it more suitable for subsequent incineration. The findings of this study serve as a reference and foundation for efficient sludge incineration., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

To address the issue of surface enrichment of A-site ions in perovskite and the resulting suppression of catalytic activity, the La 0.8 Sr 0.2 Mn 0.8 Cu 0.2 O 3 was modified by treatment with dilute nitric acid (2 mol/L) and dilute acetic acid (2 mol/L). The results show that the effect of dilute nitric acid treatment on the morphology and catalytic activity of the catalyst is more significant. The specific surface area of the catalyst after dilute nitric acid treatment (268.78 m 2 /g) is seven times higher than before treatment (37.55 m 2 /g). The low-temperature catalytic oxidation activity of HCHO of the catalyst after dilute nitric acid treatment is significantly improved, achieving a 50% HCHO oxidation efficiency at 80 °C, while the original sample requires 127 °C to achieve a 50% HCHO conversion. The excellent catalytic activity of the catalyst after dilute nitric acid treatment is related to its large specific surface area, high surface-active site density, and abundant Mn 4+ ions. Stability and water resistance experiments show that the catalyst after dilute nitric acid treatment has excellent reaction stability and good water resistance ability. The mechanism of the formaldehyde oxidation reaction is that formaldehyde is first oxidized to a dioxymethylene (DOM) intermediate and DOM dehydrogenation reaction is responsible for the formation of formate species (HCOO-)., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: The dissociation of antigen-antibody complexes has been utilized to enhance the accuracy of serological tests for infectious diseases, including Dirofilaria immitis. Currently, the antigen detected by available tests is primarily a glycoprotein found in the reproductive tract of female worms. However, this antigen can become inaccessible when bound to excessive circulating antibodies, leading to reduced test sensitivity and false-negative results. Acid and heat treatments of the sera or plasma have been established as reliable methods for inducing immune complex dissociation (ICD). Previous antigen testing for heartworm infection in dogs and cats has demonstrated that these treatments improve the diagnostic sensitivity without compromising specificity. This study aims to evaluate the performance of four distinct ICD methods in the detection of D. immitis antigen., Methods: We utilized twofold serial dilutions of a well-characterized plasma (ranging from 1:2 to 1:4096) obtained from a D. immitis-infected dog to simulate the diverse antigen levels encountered in real-life infected dogs. The presence of antigen in the diluted samples, both without treatment and treated with four ICD protocols, was assessed in triplicate visually using DiroCHEK ® by observing color changes. OD values were also obtained using the microplate reader SpectraMax® i Series-Spectramax Id3. A Factorial ANOVA test was conducted to compare the OD values between samples with and without treatments., Results: The highest dilution at which color changes were observed was 1:128 for untreated samples and for samples subjected to acid treatments in ICD-3 and the hybrid ICD-4 protocol. In contrast, both heat treatment protocols (ICD-1 and ICD-2) exhibited color changes at a 512-fold dilution. The OD values in samples subjected to heat treatment were significantly higher than those in untreated samples, up to dilutions of 512-fold. Although OD values tended to be higher in samples subjected to acid treatment and the hybrid protocol compared to untreated samples up to a 128-fold dilution, this difference was not significant as the samples underwent further dilution., Conclusions: Our findings affirm that heat treatments, rather than acid treatment, efficiently enhance the detection of D. immitis antigen by liberating the sequestered antigen from the immune complexes., (© 2023. The Author(s).)

Increasing energy demands and growing environmental concerns regarding the consumption of fossil fuels are important motivations for the development of clean and sustainable energy sources. A triboelectric nanogenerator (TENG) is a promising energy technology that harnesses mechanical energy from the ambient environment by converting it into electrical energy. In this work, the enhancement of the energy conversion performance of a natural rubber (NR)-based TENG has been proposed by using modified activated carbon (AC). The effect of surface modification techniques, including acid treatments and plasma treatment for AC material on TENG performance, are investigated. The TENG fabricated from the NR incorporated with the modified AC using N 2 plasma showed superior electrical output performance, which was attributed to the modification by N 2 plasma introducing changes in the surface chemistry of AC, leading to the improved dielectric property of the NR-AC composite, which contributes to the enhanced triboelectric charge density. The highest power density of 2.65 mW/m 2 was obtained from the NR-AC (N 2 plasma-treated) TENG. This research provides a key insight into the modification of AC for the development of TENG with high energy conversion performance that could be useful for other future applications such as PM2.5 removal or CO 2 capture.

Converting CO 2 into valuable chemicals and fuels through clean and renewable energy electricity provides a way to achieve sustainable development for human societies. In this study, carbon coated nickel catalysts (Ni@NCT) were prepared by solvothermal and high-temperature pyrolysis methods. A series of Ni@NC-X catalysts were obtained by pickling with different kinds of acids for electrochemical CO 2 reduction reaction (ECRR). The results show that Ni@NC-N treated with nitric acid has the highest selectivity but lower activity, Ni@NC-S treated with sulfuric acid has the lowest selectivity, and Ni@NC-Cl treated with hydrochloric acid shows the best activity and good selectivity. At -1.16 V, Ni@NC-Cl has a considerable CO yield of 472.9 μmol h -1 cm -2 , which is significantly superior to Ni@NC-N (327.5), Ni@NC-S (295.6) and Ni@NC (270.8). The controlled experiments show that there is a synergistic effect between Ni and N. The chlorine adsorbed on the surface can promote the performance of ECRR. The poisoning experiments indicate that the contribution of surface Ni atoms to the ECRR is very small, and the increase of activity is mainly due to the nitrogen doped carbon coated Ni particles. The relationship between activity and selectivity of ECRR on different acid-washed catalysts was correlated by theoretical calculations for the first time, which is also in good agreement with the experimental results., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The accurate calculation of the contribution which provided by clay minerals in coal on methane adsorption not only bares a significant importance for evaluating the effectiveness of acid stimulation in improving permeability and estimating the coalbed methane reserves but also serves a guide for the governance and utilization of methane resources. In this study, hydrochloric acid (HCl) and hydrofluoric acid (HF) were used to remove specific minerals in Qingdong coal samples. We firstly analyzed the mineral compositions of coal samples with different acidification treatments based on the X-ray diffraction (XRD) experiments, together with analysis of the changes in pore morphology and adsorption capacity. The results showed that acidification did not significantly change the shape of the pores, which remained slit-/plate-like pore. However, the altered adsorption capacity of the coal samples was attributed to changes in pore structure and mineral distribution. Acid erosion of mesopores promoted the transition from mesopores to macropores, contributing to an increase of 8.4% and 24.36% in the percentage of macropores in coal samples treated with HCl and HF, respectively. Fractal dimension D 1 grew from 2.2193 to 2.3888 and 2.2572, respectively, but D 2 decreased from 2.6146 to 2.5814 and 2.5433, indicating an increment in pore surface roughness and a simplification of the pore structure. The mineral richness of the coal seams should be taken into consideration when applying acid stimulation to increase permeability due to that the acidification products may block the passage of gas migration when the mineral content is slight, which can hinder gas extraction. The aim of this study is to quantitatively determine the contribution rate of clay minerals in coal to methane adsorption with a calculation method is provided by combining pore parameters and limit adsorption capacity, resulting in a contribution rate of 15%., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Transition metal-embedded heteroatom carbon composites are regarded as an important branch of bifunctional catalysts for rechargeable Zn-air batteries. The inevitable transition metal particles on the carbon skeleton may affect the availability of the metal-heteroatom-carbon catalytic site. Herein, we propose an acid treatment strategy to remove the bare transition metal particles, thus regulating the electrochemical surface area. The OER activities are highly related to the electrochemical surface area for the catalysts with different acid treatment times. In addition, there exists an optimal acid treatment time to achieve the highest ORR and OER activities with the ΔE value of 0.75 V. Given the superior bifunctional activities after acid treatment, we further assemble the rechargeable Zn-air batteries with the optimal catalyst, which achieves a peak power density of 364 mW cm -2 and long cycling life of 500 h at 10 mA cm -2 . This work affords an efficient strategy to enhance the ORR/OER activities and may guide the design of transition metal/heteroatom carbon composites., (© 2023 Wiley-VCH GmbH.)

Background: Feline heartworm disease (HWD) is a complex and often misdiagnosed disease in cats, caused by the filarial nematode Dirofilaria immitis. Despite its significant impact, studies reporting the prevalence of D. immitis in apparently healthy pet cats in the USA are lacking., Methods: To investigate feline heartworm seroprevalence in apparently healthy pet cats in the USA, serum samples (n = 2165) collected from cats across 47 states and Washington District of Columbia were analyzed for D. immitis antibody (Heska Corp.) and antigen (DiroCHEK®; Zoetis Inc.) with and without acid treatment of the samples., Results: Antibodies to D. immitis antibodies were identified in 3.5% (76/2165) of cats from 26 states, with a significantly higher prevalence in cats from the westernmost US states (West region; 5.4%, 23/429) compared to those from the South (3.8%, 32/847), Midwest (2.7%, 9/338) and Northeast regions (2.2%, 12/551) (P < 0.04). Antigen from D. immitis was detected in 0.3% (6/2165) of cats, which was significantly lower than the antibody detection (P < 10 -4 ), and no samples were positive for both antibody and antigen., Conclusions: This is the largest antibody-based, nationwide serosurvey of feline heartworm in an apparently healthy cat population, and the results suggest that cats in the USA have a high risk of exposure to D. immitis-infected mosquitoes. The high nationwide prevalence (3.5%) indicates that the true prevalence of cats infected with D. immitis in the USA may be significantly underestimated. Our findings emphasize the need for increased awareness and routine testing of cats for heartworm infection, especially in non-endemic areas of the USA. Clinicians should consider appropriate use of broad-spectrum veterinary-approved parasiticides and lifestyle management in feline patients to reduce the risk of infection. Future studies should focus on evaluating the D. immitis infection status in healthy cats and developing better diagnostic assays to detect this complex infection., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Introduction: This study evaluated the microtensile bond strength of calcium silicate-based sealers and epoxy resin-based sealer, depending on the use of phosphoric acid (PA) etching before immediate resin restoration., Methods: Exposed dentin surfaces of extracted human third molars were randomly assigned to 3 groups depending on sealer type (AH Plus [Dentsply DeTrey], CeraSeal [Meta Biomed Co.], and EndoSeal MTA [Maruchi]). Half of the samples were treated with PA for 30 seconds, and the other half were cleaned with water. Completely untreated specimens were used as controls. Self-etching adhesive (Clearfil SE Bond, Kuraray) was applied and composite resin (Tetric N-Ceram, Ivoclar Vivadent) was used to create build-ups. After 24 hours, the microtensile bond strength was measured (EZ Test, Shimadzu Co.). The failure mode was determined by light microscopy and scanning electron microscopy. One-way analysis of variance with the Bonferroni correction was used to analyze the data (P < .05)., Results: The bond strength of the water-washed dentin surfaces in the calcium silicate-based sealer groups did not differ significantly from those of the control surfaces but the PA-pretreated surfaces exhibited relatively low-bond strength. The AH Plus-treated group had lower bond strength than the control group when no PA treatment was applied, but PA treatment restored the bond strength. The adhesive failure mode was most frequently found in the AH Plus group without PA etching., Conclusions: When a water-soluble calcium silicate-based sealer is used, sufficient bond strength can be obtained by washing with water alone, with no need for PA use., (Copyright © 2023 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Frequent oil spills have caused serious consequences to the ecosystem and environment. Therefore, in order to reduce and eliminate the impact of oil spills on biology and the environment, oil spill remediation materials must be considered. As a kind of cheap and biodegradable natural organic cellulose oil-absorbing material, straw has an important practical significance in the treatment of oil spills. In order to improve the ability of rice straw to absorb crude oil, rice straw was first treated with acid and was then modified with sodium dodecyl sulfate (SDS) through a simple charge effect. Finally, the performance of oil absorption was tested and evaluated. The results illustrate that the oil absorption performance was greatly improved under the conditions of 10% H 2 SO 4 , for a 90 min reaction at 90 °C, under 2% SDS, and reacted for 120 min at 20 °C, and the rate of adsorption for rice straw to crude oil was raised by 3.33 g/g (0.83 to 4.16). Then, the rice stalks before and after the modification were characterized. Contact angle analysis shows that the modified rice stalks display better hydrophobic-lipophilic properties than unmodified rice stalks. The rice straw was characterized by XRD and TGA, and the surface structure of the rice straw was characterized by FTIR and SEM, which explain the mechanism of surface-modified rice straws with SDS to improve their oil absorption capacity.

A sub-bituminous natural coal sample (R.C) was treated with sulfuric acid (S.C) and nitric acid (N.C) as modified products and enhanced adsorbents for obtaining ciprofloxacin (CFX) antibiotic residuals from water. The characterization studied demonstrates enhancement in the surface area and the incorporation of new active oxygenated, sulfur-bearing, and nitrogen-bearing chemical groups into the structure of coal samples. This was reflected in the adsorption capacities that were enhanced from 164.08 mg/g (R.C) to 489.2 mg/g and 518.5 mg/g for N.C and S.C, respectively. The impact of the acid modification processes was evaluated based on the energetic and steric properties of their adsorption systems considering the parameters of the advanced monolayer equilibrium model with one energy site. The determined occupied active sites' density of R.C (46.32-61.44 mg/g), N.C (168.7-364.9 mg/g), and S.C (159.2-249.9 mg/g) reflects an increase in the quantities of active centers after the acid treatment processes, especially with HNO 3 . The higher efficiencies of the active sites of S.C to adsorb more CFX molecules ( n = 2.08-2.31) than N.C ( n = 1.41-2.16) illustrate its higher adsorption capacity. The energetic investigation [adsorption (˂40 kJ/mol) and Gaussian (˂8 kJ/mol) energies] suggested adsorption of CFX by N.C and S.C mainly by physical processes such as van der Waals forces, hydrogen bonding, dipole bonding, and π-π interactions. Moreover, the determined thermodynamic functions including entropy, internal energy, and free enthalpy reflect the spontaneous and endothermic uptake of CFX on the surfaces of N.C and S.C., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Al-Labadi, Shemy, Ghidan, Allam, Kálmán, Ajarem, Luo, Wang and Abukhadra.)

The complete catalytic oxidation of formaldehyde (HCHO) to CO 2 and H 2 O at room temperature is a green route for indoor HCHO removal. Zeolite is an excellent carrier material for HCHO oxidation due to its large surface area, intricate pores and high adsorption capacity. However, the zeolite-supported noble metal catalysts have currently shown relatively low activity especially at room temperature. In this work, we present a facile acid treatment strategy for zeolite catalysts to improve the hydroxyl concentration and further enhance their catalytic activity for HCHO oxidation. Activity tests illustrated that HCHO could be completely oxidized to CO 2 and H 2 O at a nearly 100% conversion rate with a weight hourly space velocity (WHSV) of 150,000 mL/(g∙hr) at 25°C, when the support of Pd/USY catalysts was pretreated by hydrochloric acid with a concentration of 0.20 mol/L. The characterization results revealed that the active hydroxyl groups originated from the dealumination in the acid treatment play a key role in the HCHO oxidation reaction. The deduced reaction mechanism suggests that bridging hydroxyl groups may oxidize HCHO to dioxymethylene (DOM) species and terminal hydroxyl groups are responsible for the transformation of DOM groups to formate (HCOO) species., (Copyright © 2022. Published by Elsevier B.V.)

In the present work, the potential of Cephalosporium strain in degrading the pre-treated (ultraviolet irradiation followed by nitric acid treatment) low-density polyethylene and high-density polyethylene films was investigated. Our observations revealed a significant weight reduction of 24.53 ± 0.73% and 18.22 ± 0.31% in pre-treated low-density polyethylene and high-density polyethylene films respectively, after 56 days of incubation with the Cephalosporium strain. Changes in the physicochemical properties of the mineral salt medium (MSM) were studied to assess the extent of biodegradation. The pH of the MSM decreased gradually during the incubation period, whereas its total dissolved solids and conductivity values increased steadily. Fourier transform infrared spectroscopy (FTIR) indicated the formation of hydroxyl and C = C groups in biodegraded low-density polyethylene films, while in the case of biodegraded high-density polyethylene films it indicated the [Formula: see text]CH 2 stretching. Furthermore, the thermogravimetric analysis (TGA) revealed an enhancement in the thermal stabilities of both the LDPE and HDPE films post the biodegradation. Modifications in the polymer surface morphologies after UV irradiation, chemical treatment, and biodegradation steps were visualized via scanning electron microscopy (SEM) analysis. All our observations confirm the ability of the Cephalosporium strain in biodegrading the pre-treated LDPE and HDPE films., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

This research focuses on studying the effects of various pretreatment types on a PtCu/C catalyst synthesized by the co-deposition of metal precursors. The treatment in a 1 M HNO 3 solution for 1 h is shown to result in a slight increase in activity in the oxygen electroreduction reaction (both the mass activity and specific activity calculated for the value of the electrochemically active surface area). The sample obtained after the thermal treatment, which is carried out at 350 °C under an argon atmosphere for 1 h, demonstrates 1.7 times higher specific activity than the sample before the treatment. The durability testing results obtained by the stress testing method in a potential range of 0.6-1.4 V during 2000 cycles show that the PtCu/C catalysts after both the acid treatment and the thermal treatment are characterized by higher residual activity than the sample in the "as-prepared" state.

Using nanocarriers to load antimicrobial agent instead of direct incorporating into film matrix could avoid burst release. Halloysite nanotubes (HNTs) are natural clays with a unique tubular structure; therefore in many studies it served as carriers to achieve a controlled release of active agents. However, when HNTs biocomposites were loaded into packaging film, the antimicrobial activity was reduced too seriously to preserve the packaged food. This study aimed to improving preservation properties of the fabricated films from two perspectives: enlarging the loading capacity of the carrier, and increasing the concentration of HNTs biocomposites. Brunauer, Emmett, Teller's test (BET) and thermogravimetric analysis (TGA) were conducted to evaluate the performance of acid treated nanocomposites. Results showed that acid treatment expanded the lumen of HNTs, increasing the loading capacity of cinnamaldehyde (Cin) from 14.6 wt% to 25.0 wt%. Active packaging films were then fabricated by incorporating Cin loaded HNTs into poly(lactic acid) matrix, and it revealed bionanocomposites at 30 wt% achieved the optimum film, considering the mechanical performance and controlled release of Cin. Cumulative release rate of the films were further verified by the fumigant antimicrobial activity. This study demonstrates a solution for improving the antimicrobial properties of packaging film without comprising mechanical strength., Competing Interests: Declaration of competing interest All authors declare that there is no competing financial interest., (Copyright © 2022 Elsevier B.V. All rights reserved.)

In this study, an acid-treated-activated carbon was prepared from chestnut oak shell carbonization followed by modification with hydrochloric acid/nitric acid and then used as a new sorbent for headspace needle-trap extraction of chlorophenol compounds from aqueous solutions. Different techniques, including scanning electron microscopy, nitrogen adsorption-desorption analysis, and Fourier transform-infrared spectroscopy were used for the characterization of the sorbents. The effects of some experimental parameters, including the temperature, pH, sorbent amount, and time of extraction were optimized. The developed method is fast and sensitive, providing low and sub ng/L detection limits. The limits of detection and quantification were in the range of 0.75-5 and 5-15 ng/ml, respectively, and the equilibrium time was 20 min. Wide linearity in the range of 15-2000 ng/L with R 2  > 0.9993 was obtained. Repeatability of the method was accessed at 50, 100, and 200 ng/L concentration levels and RSD% of 5%-12% was achieved. The introduced method was applied for analyzing real water samples containing spiked chlorophenols, and the relative recovery values were found to be in the range of 84%-99% at the concentration levels of 50, 100 and 200 ng/L., (© 2022 Wiley-VCH GmbH.)

Polyimide (PI) films with excellent heat resistance and outstanding mechanical properties have been widely researched in microelectronics and aerospace fields. However, most PI films can only be used under ordinary conditions due to their instability of dimension. The fabrication of multifunctional PI films for harsh conditions is still a challenge. Herein, flexible, low coefficient of thermal expansion (CTE) and improved mechanical properties films modified by carboxylated carbon nanotube (C-CNT) were fabricated. Acid treatment was adapted to adjust the surface characteristics by using a mixture of concentrated H 2 SO 4 /HNO 3 solution to introduce carboxyl groups on the surface and improve the interfacial performance between the CNT and matrix. Moreover, different C-CNT concentrations of 0, 1, 3, 5, 7, and 9 wt.% were synthesized to use for the PI film fabrication. The results demonstrated that the 9 wt.% and 5 wt.% C-CNT/PI films possessed the lowest CTE value and the highest mechanical properties. In addition, the thermal stability of the C-CNT/PI films was improved, making them promising applications in precise and harsh environments.

Li-rich layered oxides (LRLO) with specific energies beyond 900 Wh kg -1 are one promising class of high-energy cathode materials. Their high Mn-content allows reducing both costs and the environmental footprint. In this work, Co-free Li 1.2 Mn 0.6 Ni 0.2 O 2 was investigated. A simple water and acid treatment step followed by a thermal treatment was applied to the LRLO to reduce surface impurities and to establish an artificial cathode electrolyte interface. Samples treated at 300 °C show an improved cycling behavior with specific first cycle capacities of up to 272 mAh g -1 , whereas powders treated at 900 °C were electrochemically deactivated due to major structural changes of the active compounds. Surface sensitive analytical methods were used to characterize the structural and chemical changes compared to the bulk material. Online DEMS measurements were conducted to get a deeper understanding of the effect of the treatment strategy on O 2 and CO 2 evolution during electrochemical cycling., (© 2022 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

The nanocomposites of poly(vinylidene fluoride) (PVDF) with pristine graphene nanoflakes (GNF) and a multi-wall carbon nanotube (MWCNT) were prepared by the solution casting method. Additionally, the GNF and MWCNT were functionalized by acid treatment, and nanocomposites of the acid-treated MWCNT/GNF and PVDF were prepared in the same method. The effect of the acid treatment of MWCNT and GNF on the mechanical, thermal and thermo-oxidative stability and the thermal conductivity of the MWCNT/GNF-PVDF nanocomposites was evaluated, and the results were compared with the untreated MWCNT/GNF-PVDF nanocomposites. In both cases, the amount of GNF and MWCNT was varied to observe and compare their thermal and mechanical properties. The functionalization of the GNF or MWCNT resulted in the change in the crystallization and melting behavior of the nanocomposites, as confirmed by the differential scanning calorimetry analysis. The addition of the functionalized GNF/MWCNT led to the improved thermal stability of the PVDF nanocomposites compared to that of the non-functionalized GNF/MWCNT-PVDF nanocomposites. The thermal and electrical conductivity of the functionalized and non-functionalized GNF/MWCNT-PVDF composites were also measured and compared. The functional groups, crystal structure, microstructure and morphology of the nanocomposites were characterized by Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively., Competing Interests: The authors declare no conflict of interest.

Petroleum-based polymers are not susceptible to microorganisms because of its high molecular weight. Acid treatments convert the polymers into a more oxidized form having low molecular weight. The present in-vitro degradation study focuses on the potential of Cephalosporium species to degrade acid-treated polystyrene (PS) and low-density polyethylene (LDPE) films. A weight loss of around 12% and 13% was achieved for PS and LDPE films respectively in eight weeks of treatment with Cephalosporium species. Fourier transform infrared spectroscopy analysis showed the formation of hydroxyl and carbonyl groups in nitric acid treated PS and LDPE films, respectively. Scanning electron microscopy indicated modifications in the surface morphology of PS and LDPE films after chemical and microbial treatment. An increase in crystallinity of pre-treated polymer samples was observed after fungal treatment. The observations of present study confirmed the enzymatic deterioration and assimilation of pre-treated PS and LDPE samples by the microbial species., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Insoluble bound polyphenols (ISBP) are polyphenolic compounds linked to the food matrix with different interactions limiting both their water extractability and consequent bioaccessibility. The health-promoting potential of polyphenols is historically known and well-demonstrated; specifically, Annurca apple polyphenols were studied both in vitro and in vivo for their effect in controlling cholesterol plasma levels. The aim of the study was the preparation of nutraceutical products based on Annurca apple polyphenolic fraction through the application of a technological process (acid treatment) able to release the ISBP from Annurca apple food matrix and increase polyphenol bioaccessibility. Lyophilized annurca apple (LAA) underwent acid treatment (ATLAA), and differences in released polyphenol levels were analysed by DAD-HPLC. Free-polyphenol levels in samples treated under acid conditions were higher than in untreated ones; in particular, for oligomeric flavan-3-ols (+168% procyanidin B2, +42.97% procyanidin B1 and B2, +156.99% procyanidin C1), catechin (+512.20%), and gallic acid (+707.77%). Furthermore, ATLAA underwent an in vitro gastrointestinal digestion to evaluate the bioaccessibility of contained polyphenols, in comparison to the untreated Annurca apple. The bioaccessibility study indicates a valuable preservation of polyphenolic fraction compared to the control.

Polyetheretherketone (PEEK) is the only polymer material that can replace titanium implants in the field of orthopedics. This is because the mechanical properties of PEEK are similar to those of bone, and PEEK has natural radiolucency, chemical stability, and sterilization resistance. Despite these advantages, PEEK has a disadvantage-that it is bio-inert. Therefore, many studies have attempted to change the bio-inertness of PEEK into bioactivity. Among them, a method of forming pores by acid treatment is attracting attention. In this study, an attempt was made to form pores on the surface of PEEK implant using a mixed acid of sulfuric acid and nitric acid. As a result, it was found that the condition when the PEEK surface is in contact with the acid is very important. That is, it was possible to form single-layered nanopores on the surface by contacting PEEK with a mixed acid under ultrasound. Additionally, by immobilizing type I collagen on the porous PEEK surface through dopamine coating, it was possible to obtain collagen-immobilized porous PEEK (P-PEEK-Col) with high compatibility with osteoblasts. This P-PEEK-Col has high potential for use as a bone substitute that promotes bone formation.

In this paper, a universal technology is proposed for processing low-titanium mineral raw material-apatite-nepheline ore waste, including its treatment with sulfuric or hydrochloric acid in a two-stage mode with a sequential increase in the concentration. This technique allowed us to remove nepheline and apatite in the first stage and achieve a titanium mineral content of TiO 2 of more than 30%; in the second stage, we were able to convert the titanium into its precursors-titanyl sulfate monohydrate TiOSO 4 ·H 2 O and a hybrid rutile-silica composition. The key stage in the sorbent synthesis is the reaction of the precursor with a phosphoric acid solution. The preferred sequence of operations begins with the mechanical activation of the precursor, causing morphological changes in it, and subsequent treatment with phosphoric acid at different concentrations under atmospheric conditions and in an autoclave, accompanied by phase transformations. Conditions for the chemical reactions which regulated the composition and structure of the final product and, accordingly, its sorption activity were found. With the help of XFA, the phase compositions of the sorbents were identified, including the individual crystalline phase α-TiP obtained from TS or the crystalline phase αTi(HPO 4 ) 2 ∙H 2 O, which is in an amorphous silica matrix obtained from a rutile-silica composition.

This paper studies the impact of hot pressing on the electrical and thermal performance of thick (thickness >5 μm) conducting polymer poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films after acid treatment. Thick conducting polymer films usually exhibit low electrical and thermal conductivities similar to bulk polymer because charge and heat carriers are easily scattered by the irregular arrangement of crystalline domains inside the polymer. In this work, the in-plane electrical conductivity of thick hot-pressed PEDOT:PSS film exceeded 1500 S/cm, and 50% enhancement was obtained in comparison with its non-hot-pressed counterparts. Its in-plane thermal conductivity reached as high as 1.11 W/mK (improved by almost 100% compared to acid-treated PEDOT:PSS films), which is comparable to that of some commercial thermal pads. Such electrical and thermal enhancement via the hot-pressing process is attributed to the optimized morphology and microstructures, which provide short paths for thermal and electrical transportation. We have also demonstrated that the hot-pressed PEDOT:PSS films could be potentially utilized as a flexible conductor and heat spreader for application in flexible electronics and thermal management, respectively. This study not only offers a new insight into the process-property relationship for conducting polymers but also further enables the use of PEDOT:PSS films with simultaneously improved electrical and thermal performance in practical applications, such as thermal management for organic electrodes in batteries, flexible electronics, soft robotics, and bioelectronics.

Self-adhering implantable devices, which can be immobilized inside the bodies without suturing nor organic glues, made of metallic biomaterials would be optimal devices for preventing device-related complications such as device migration after implantation. We reported previously that acid-treated commercially-pure titanium (CpTi) adhered directly and immediately on hydrous non-keratinized soft tissues. Herein, we investigated the influence of sandblasting as pretreatment for acid-treated CpTi to increase its soft tissue adhesiveness. First, the effects of sandblasting conditions (i.e., pressure, distance and time) were investigated in terms of the sandblasted surface area and the degree of deformation (i.e., internal stress formation) of CpTi films. The effect of the sandblasting on the immediate soft tissue adhesion of acid-treated CpTi was investigated using an ex vivo shear adhesion test with mouse dermal tissues. The optimal sandblasting pretreatment remarkably improved the soft tissue adhesion strength of acid-treated CpTi (102 ± 19 kPa) compared with the non-sandblasted counterparts (41 ± 2 kPa). Finally, the CpTi adhesive was applied for immobilizing a near field communication (NFC) device in vivo, and was shown to have strong immediate adhesion to muscle fascia., (Copyright © 2021 Elsevier B.V. All rights reserved.)

African swine fever is a widespread and highly contagious disease in the porcine population, which is caused by African swine fever virus (ASFV). The PCR and ELISA detection methods are the main conventional diagnostic methods for ASFV antigen/antibody detection in the field. However, these methods have limitations of expensive equipment, trained technicians, and time-consuming results. Thus, a rapid, inexpensive, accurate and on-site detection method is urgently needed. Here we describe a double-antigen-sandwich lateral-flow assay based on gold nanoparticle-conjugated ASFV major capsid protein p72, which can detect ASFV antibody in serum samples with high sensitivity and specificity in 10 min and the results can be determined by naked eyes. A lateral flow assay was established by using yeast-expressed and acid-treated ASFV p72 conjugated with gold nanoparticles, which are synthesized by seeding method. A high coincidence (97.8%) of the assay was determined using clinical serum compared to a commercial ELISA kit. In addition, our lateral flow strip can detect as far as 1:10,000 diluted clinically positive serum for demonstration of high sensitivity. In summary, the assay developed here was shown to be rapid, inexpensive, accurate and highly selective. It represents a reliable method for on-site ASFV antibody detection and may help to control the ASFV pandemic., Competing Interests: Outside of the submitted work, we hold a patent (CN 202110522777.4) issued for the preparation method and the application of African swine fever virus capsid protein p72 trimer., (Copyright © 2022 Zhu, Meng, Zhang, Bu, Zhao and Meng.)

In this study, acid treated Punica granatum (PG) peels were used for effective removal of Diamond green (DG) dye, commonly found in textile industry waste. Acid treatment enhanced the efficiency of this process along with increasing shelf life and stability of bio-adsorbent by reducing fungal attack risk. Optimized operational parameters for removing DG dye using PG peels powder were: 35-minute contact time, 75 rpm agitation speed, 50°C temperature and pH of 2. Isothermal study results showed that maximum dye removing capacity was 29.08 mg/g. ΔG and ΔH values were -6.384 and -0.05 kJ/mol, respectively indicating that DG dye adsorption on acid treated PG peels is spontaneous and exothermic in nature. It was found that for batch scale adsorptive removal of basic dyes like DG, acid treated Punica granatum peels were effective bio-waste that can be used from our indigenous sources in an effective way.

This study used the bark of the forest species Campomanesia guazumifolia modified with H 2 SO 4 to absorb the anti-inflammatory ketoprofen from aqueous solutions. FTIR spectra confirmed that the main bands remained after the chemical treatment, with the appearance of two new bands related to the elongation of the carbonyl group present in hemicellulose. Micrographs confirmed that the surface started to contain a new textural shape after acid activation, having new pores and cavities. The drug adsorption's optimum conditions were obtained by response surface methodology (RSM). The adsorption was favored at acidic pH (2). The dosage of 1 g L -1 was considered ideal, obtaining good indications of removal and capacity. The Elovich model very well represented the kinetic curves. The isotherm studies indicated that the increase in temperature negatively affected the adsorption of ketoprofen. A maximum adsorption capacity of 158.3 mg g -1 was obtained at the lower temperature of 298 K. Langmuir was the best-fit isotherm. Thermodynamic parameters confirmed the exothermic nature of the system (ΔH 0 = -8.78 kJ mol -1 ). In treating a simulated effluent containing different drugs and salts, the removal values were 35, 50, and 80% at 15, 30, and 180 min, respectively. Therefore, the development of adsorbent from the bark of Campomanesia guazumifolia treated with H 2 SO 4 represents a remarkable alternative for use in effluent treatment containing ketoprofen., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

DT0-activated carbons modified with HCl and HNO 3 acids, which were used for the first time in the catalytic process of alpha-pinene isomerization, are presented in this study. The carbon materials DT0, DT0&#95;HCl, DT0&#95;HNO 3 , and DT0&#95;HCl&#95;HNO 3 were examined with the following methods: XRF, SEM, EDX, XPS, FT-IR, XRD, and N 2 adsorption at -196 °C. It was shown that DT0&#95;HCl&#95;HNO 3 -activated carbon was the most active material in the alpha-pinene isomerization process. Detailed studies of alpha-pinene isomerization were carried out over this carbon by changing the reaction parameters such as time (5-180 min) and temperature (60-175 °C). The 100% conversion of alpha-pinene was achieved at the temperature of 160 °C and catalyst content of 5 wt% after 3 h over the DT0&#95;HCl&#95;HNO 3 catalyst. Camphene and limonene were the main products of the alpha-pinene isomerization reaction.

Halloysite Nanotubes (HNT) are chemically similar to clay, which makes them incompatible with non-polar rubbers such as natural rubber (NR). Modification of NR into a polar rubber is of interest. In this work, Epoxidized Natural Rubber (ENR) was prepared in order to obtain a composite that could assure filler-matrix compatibility. However, the performance of this composite was still not satisfactory, so an alternative to the basic HNT filler was pursued. The surface area of HNT was further increased by etching with acid; the specific surface increased with treatment time. The FTIR spectra confirmed selective etching on the Al-OH surface of HNT with reduction in peak intensity in the regions 3750-3600 cm -1 and 825-725 cm -1 , indicating decrease in Al-OH structures. The use of acid-treated HNT improved modulus, tensile strength, and tear strength of the filled composites. This was attributed to the filler-matrix interactions of acid-treated HNT with ENR. Further evidence was found from the Payne effect being reduced to 44.2% through acid treatment of the filler. As for the strain-induced crystallization (SIC) in the composites, the stress-strain curves correlated well with the degree of crystallinity observed from synchrotron wide-angle X-ray scattering.

In order to satisfy the growing requirements of wearable electronic devices, 1D fiber-shaped devices with outstanding sensitivity, flexibility, and stability are urgently needed. In this study, a novel inorganic-organic heterojunction fibrous photodetector (FPD) based on poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) and highly ordered TiO 2 nanotube array is fabricated, which endows a high responsivity, large external quantum efficiency, and fast response speed at 3 V bias. To further ameliorate its performance in the self-powered mode, a facile acid treatment is adopted and the assembled H-PEDOT:PSS/TiO 2 FPD demonstrates outstanding self-powered properties with ≈3000% responsivity enhancement (161 mA W -1 at 0 V under 365 nm irradiation, photocurrent enhancement of ≈50 times) compared with the untreated device. It is found that the concentrated H 2 SO 4 post-treatment helps decrease the tube wall thickness of TiO 2 and partially removes the insulated PSS component in PEDOT:PSS, leading to enhanced conductivity and facilitated charge transportation, and thereby superb responsivity/photocurrent enhancement of self-powered H-PEDOT:PSS/TiO 2 FPD. This low-cost and high-performance self-powered FPD shows high potential for applications in wearable electronic devices., (© 2021 Wiley-VCH GmbH.)

The objective of this study was to investigate the effect of three different treatments on the morphology, microstructure, and the thermal characteristics of a montmorillonite (Mt) sample, by using hydrochloric acid (HCl), tributyl tetradecyl phosphonium chloride (TTPC) surfactant, and γ-methacryloxypropyltrimethoxysilane (γ-MPS). The resultant nanofillers were characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), nitrogen adsorption-desorption analysis, X-ray fluorescence spectrometry (XRF), and thermogravimetric analysis (TGA). The results showed that the amount of chemical grafting of the γ-MPS was increased after the acid treatment, whereas the amount of intercalation of the TTPC surfactant was decreased. The preintercalation of TTPC or silylation of γ-MPS, for the Mt sample, had a certain hindrance effect on its subsequent silylation or intercalation treatments. Furthermore, the effect of four different nanofillers on the thermal stability properties of the polystyrene (PS) matrix were also investigated. The results showed an increase in thermal stability for the triple-functionalized Mt, compared with the double-functionalized samples. The onset decomposition temperatures and the maximum mass loss temperatures of the PS nanocomposites were increased by 27 °C and 32 °C, respectively, by the incorporation of triple-modified Mt, as a result of the good exfoliation and dispersion of the nanolayers, more favorable polymer-nanofiller interaction, as well as the formation of a more remarkable tortuous pathway in the continuous matrix.

In this study, the novel mesoporous carbonized material (HSBE/C) was prepared from clay/carbon composite (SBE/C) treated with hydrofluoric acid (HF) for the first time, and was employed to efficiently adsorb bisphenol A (BPA) in water. Specifically, SBE/C was derived from the pyrolysis of spent bleaching earth (SBE), an industrial waste. HF removed SiO 2 from SBE/C and increased the specific surface area of HSBE/C (from 100.21 to 183.56 m 2 /g), greatly providing more adsorption sites for enhanced BPA adsorption capacity. The Langmuir monolayer maximum adsorption capacity of HSBE/C (103.32 mg/g) was much higher than the commercial activated carbon (AC) (42.53 mg/g). The adsorption process by HSBE/C followed well with the Freundlich isotherm model and the pseudo-second-order kinetic model and also was endothermic (ΔH 0 > 0) and spontaneous (ΔG 0 < 0). Based on the systematic characterization and factor experiment (temperature, dosage, initial pH, co-existing ions), BPA adsorption mechanism by HSBE/C likely included the hydrogen bonding, electrostatic interaction, and hydrophobic interaction. Moreover, there was no secondary pollution during the total adsorption process. Extraordinary, HSBE/C manifested stability by NaOH desorption regeneration. This study provides a new sight for application of waste-based materials as the promising adsorbents in the treatment of endocrine disruptors., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In this work, peanut (Arachis hypogaea) skin, a by-product generated by the agricultural production of its seeds, was employed as a precursor in the preparation of an adsorbent for the 2,4-D removal in water. The skins were treated with sulfuric acid and characterized by different techniques. The adsorption was favored at acid pH = 2 with pH pzc = 6. The dosage of 0.9 g L -1 was considered ideal, obtaining satisfactory indications of removal and capacity. The kinetic curves were well represented by the general order model, with the equilibrium reached quickly in the first 30 min for all concentrations. Adsorption isotherm studies showed that the increase in temperature negatively affected the herbicide adsorption, obtaining a maximum capacity of 246.72 mg g -1 , by the Langmuir isotherm at 298 K. The remarkable adsorption efficiency presented by the adsorbent can be associated with the presence of new functional groups on the adsorbent surface generated after the acid treatment. Thermodynamic parameters confirmed the exothermic nature of the adsorptive system. In the treatment of synthetic wastewater consisting of a mixture of herbicides and salts, a high removal efficiency (72%) of herbicides was obtained. Therefore, the development of an adsorbent derived from peanut (Arachis hypogaea) skin treated with sulfuric acid is an excellent alternative, generating remarkable removal results towards 2,4-D herbicide., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Due to its excellent mechanical and low-friction properties, polyetheretherketone (PEEK) has been widely investigated for use in orthopedic applications over the past decade. However, the bioinertness and poor osteogenic properties of PEEK have hampered its clinical application. In this study, the surface of PEEK was modified by co-treatment with hydrofluoric acid and nitric acid (AFN). The microstructures of the modified PEEK surfaces were investigated using scanning electron microscopy. The water contact angles of the surfaces were also measured. To evaluate their cytocompatibility, PEEK samples were used as substrates to culture rat bone mesenchymal stem cells, and cell adhesion, viability, and expression of specific marker genes were measured. Treatment of PEEK with AFN (PEEK-AFN) was found to enable better osteoblast adhesion, spreading, and proliferation; the activity of alkaline phosphatase (an early osteogenic differentiation marker) was also found to be enhanced post-treatment. Furthermore, PEEK-AFN was able to modulate macrophage polarization and down regulated the expression of proinflammatory factors via inhibiting the NF-κB pathway. Thus, treatment of PEEK with AFN could promote M2 polarization of the macrophages and stimulate the differentiation of osteoblasts. These results provide valuable information that could facilitate the use of PEEK-based composites as bone implant materials., (© 2020 Wiley Periodicals LLC.)

Oxidation of o-xylene was performed using alkaline battery-based catalyst doped with platinum to investigate the properties and activities. O-xylene was selected as the model of volatile organic compound (VOC) in this work. Physicochemical properties of the selected catalysts were characterized by FE/TEM (field emission transmission electron microscopy), BET (Brunauer-Emmett-Teller) analysis, XRD (X-ray powder diffraction), SEM/EDX (scanning electron microscopy/energy dispersive X-ray spectroscopy), and H 2 -TPR (hydrogen temperature programmed reduction). Major elements of the spent alkaline battery-based catalyst treated with sulfuric acid solution [SAB (400) catalyst] were manganese, zinc, iron, oxygen, carbon, chlorine, aluminum, sodium, silicon, and potassium. Increasing the doping amount of platinum on SAB (400) catalyst from 0.1 to 1 wt% increased particle size of platinum and lowered the temperature of TPR (TTP) for SAB (400) catalyst. Better redox properties were achieved with an increase in the o-xylene conversion according to the doping amount of platinum. When GHSV (gas hourly space velocity) was 40,000 h -1 , o-xylene was oxidized completely over SAB (400) catalyst and 1.0 wt% Pt/SAB(400) catalyst at temperatures of 400 °C and 280 °C, respectively.

Selective laser melting (SLM) is a promising technology capable of producing individual characteristics with a high degree of surface roughness for implants. These surfaces can be modified so as to increase their osseointegration, bone generation and biocompatibility, features which are critical to their clinical success. In this study, we evaluated the effects on preosteoblast proliferation and differentiation of titanium metal (Ti) with a high degree of roughness (Ra = 5.4266 ± 1.282 µm) prepared by SLM (SLM-Ti) that was also subjected to surface bioactive treatment by mixed acid and heat (MAH). The results showed that the MAH treatment further increased the surface roughness, wettability and apatite formation capacity of SLM-Ti, features which are useful for cell attachment and bone bonding. Quantitative measurement of osteogenic-related gene expression by RT-PCR indicated that the MC3T3-E1 cells on the SLM-Ti MAH surface presented a stronger tendency towards osteogenic differentiation at the genetic level through significantly increased expression of Alp, Ocn, Runx2 and Opn. We conclude that bio-activated SLM-Ti enhanced preosteoblast differentiation. These findings suggest that the mixed acid and heat treatment on SLM-Ti is promising method for preparing the next generation of orthopedic and dental implants because of its apatite formation and cell differentiation capability.