Content Of Groups Research Articles

Cyclic variable temperature conditioning-maintained storage quality of sweet potatoes by enhancing antioxidant activity

The study investigated the effect of cyclic variable temperature conditioning (CVTC) on the quality parameters of sweet potatoes and their relationship with the antioxidant system (phenols synthesis and reactive oxygen species metabolism). Results showed that CVTC maintained the color and normal respiratory intensity of sweet potatoes and reduced the accumulation of malondialdehyde (MDA) during storage. In detail, total phenols content (TPC) and total flavonoids content (TFC) in CVTC group were significantly higher than those in control (CK), cold storage (CS), and high temperature conditioning (HTC) groups at 8 d, with increases of 17.58% and 85.12% from day 0, respectively. Additionally, phenylalanine ammonia lyase (PAL) and hydroxycinnamoyl transferase (HCT) activities in CVTC group were significantly higher than those in CK, CS, and HTC groups at 8 d. These results showed that CVTC activated the synthesis of phenols by activating the key enzymes activities, resulting in a significant increase in total phenols and flavonoids contents. Besides, CVTC improved the superoxide anion scavenging capacity of sweet potatoes and promoted the decomposition of hydrogen peroxide (H2O2). Meanwhile, superoxide dismutase (SOD) and catalase (CAT) activities in CVTC group were significantly higher than those in CK, CS, and HTC groups in the late storage period. In conclusion, CVTC enhanced the antioxidant activity of sweet potatoes by regulating the phenols synthesis and reactive oxygen species metabolism to maintain their postharvest quality.

Effects of fish skin collagen peptide on physicochemical properties of frozen dough and quality and antioxidant activity of steamed bread

Fish skin collagen peptide (FSCP), as a bioactive peptide, holds significant potential in the food industry, particularly in enhancing the quality and nutritional attributes of frozen dough products. This research examined the impacts of FSCP addition and freezing time on water distribution, rheo-fermentation, rheological, and structural properties of dough, as well as the textural properties, internal structure, and antioxidant activity of steamed bread. The results showed that adding FSCP inhibited water migration and reduced freezable water content. After 4 weeks of freezing, the freezable water content of the FSCP-added groups decreased by 0.42% to 4.77% compared with the control. Rheo-fermentation analysis indicated that the total CO2 release volume, maximum dough development height, and CO2 retention volume initially increased with FSCP concentration, peaking at 1.5%, before decreasing with further increases in FSCP concentration. Moreover, FSCP effectively mitigated gluten freeze damage, resulting in a slower decline in disulfide bond content and viscoelasticity. Additionally, it improved the textural properties and antioxidant activity of the steamed bread. X-ray micro-CT images revealed that FSCP enhanced gas pore distribution and network density in the steamed bread. Overall, FSCP proved effective in improving the attributes of frozen dough and the final steamed bread, particularly at a 1.5% concentration. These findings suggest a promising application of FSCP in frozen dough-based products, especially in the development of functional foods.

Primary human mesenchymal stem cell culture under xeno-free conditions using surface-modified cellulose nanofiber scaffolds

Stem cell culture often requires various animal-derived components such as serum and collagen. This limits its practical use. Therefore, xeno-free (xenogeneic component-free) culture systems are receiving increased attention. Herein, we propose xeno-free, plant-derived cellulose nanofibers (CNFs) with different surface chemistry: 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized CNFs (TOCNFs) with carboxy groups and surface-sulfated CNFs (S-CNFs) for the proliferation of human mesenchymal stem cells (hMSCs) under various serum conditions. We cultured bone marrow-derived hMSCs on CNF scaffolds with various fiber lengths and functional group contents. Original CNFs were bioinert materials that did not contribute to cell adhesion. In contrast, the surface-modified CNFs facilitated the proliferation of immortalized hMSCs under normal and low-serum conditions. The TOCNFs (COONa: 1.47 mmol g−1; length: 0.53 μm), the S-CNFs (OSO3Na: 0.64 mmol g−1; 0.61 μm), and a combination of the two (1:1 by weight) enabled immortalized hMSCs to maintain their multipotency, even under serum-free conditions. Primary cultured hMSCs proliferated well on the TOCNF/S-CNF scaffolds in a completely serum-free medium, comparable to animal-derived type I collagen, although few hMSCs adhered to the standard polystyrene substrate. Our strategy of using surface-modified CNFs will inform the development of xeno-free culture systems to avoid the use of animal-derived materials for both cell culture media and scaffolds.

Lignin: A multifunctional and sustainable photothermal material for solar-driven thermoelectric generation and desalination

The abundant aromatic ring structure and a large number of oxygen-containing functional groups in the lignin offer the possibility of achieving excellent photothermal conversion ability and modulating the synthesis of metal nanoparticles. Herein, three kinds of the lignin with different functional group content were employed to investigate the potential influence on the particle size and the solution stability of the CuS through two reaction pathways. The result of various characterizations indicated that the higher the oxygen-containing functional group content (4.83 mmol/g) of lignin, the smaller the size of CuS nanoparticles (∼80 nm) in solution. And the smaller and homogeneously dispersed CuS offered a higher surface temperature for the solar-driven heat-generating materials. The regulation mechanism was also proposed based on the result of the molecular dynamics simulation and DFT calculation. Subsequently, the photothermal film (Route2 DTAL-PVA-30) and solar-driven aerogel evaporator (Route2 DTAL-AG3) were successfully prepared using the lignin-guided stabilization solution of CuS nanoparticles. The photothermal conversion efficiency of 49.43 % and the equilibrium voltage of 266 mV can be achieved by the Route2 DTAL-PVA-30 under 1 sun using a thermoelectric generator. The Route2 DTAL-AG3 exhibited promising salt-rejecting property and outstanding acid and alkali resistance performance, reaching an evaporation rate of up to 1.93 kg/(m2 h) in the 3.5 wt% seawater under 1sun. This work may provide a novel strategy to realize the regulatory role of lignin in the metal synthesis and achieve the high value-added applications of the lignin.

AQDS-functionalized biochar enhances the bioreduction of Cr(VI) by Shewanella putrefaciens CN32

The bioreduction of toxic chromium(VI) to sparingly soluble chromium(III) represents an environmentally friendly and cost-effective method for remediating Cr contamination. Usually, this bioreduction process is slow and requires the addition of quinone compounds as electron shuttles to enhance the reaction rate. However, the dissolved quinone compounds are susceptible to loss with water flow, thereby limiting their effectiveness. To address this challenge, this study loaded anthraquinone-2,6- disulfonate (AQDS), a typical quinone compound, onto biochar (BC) to create a novel solid-phase electron mediator (BC-AQDS) that can sustainably promote Cr(VI) bioreduction. The experimental results demonstrated that BC-AQDS significantly promoted the bioreduction of Cr(VI), where the reaction rate constant increased by 4.81 times, and the reduction extent increased by 38.31%. X-ray photoelectron spectroscopy and Fourier-Transform Infrared Spectroscopy analysis revealed that AQDS replaced the -OH functional groups on the BC surface to form BC-AQDS. Upon receiving electrons from CN32, BC-AQDS was reduced to BC-AH2DS, which subsequently facilitated the reduction of Cr(VI) to Cr(III). This redox cycle between BC-AQDS and BC-AH2DS effectively enhanced the bioreduction rate of Cr(VI). Our study also found that a lower carbonization temperature of BC resulted in a higher surface -OH functional group content, enabling a greater load of AQDS and a more pronounced enhancement effect on the bioreduction of Cr(VI). Additionally, a smaller particle size of BC and a higher dosage of BC-AQDS further contributed to the enhancement of Cr(VI) bioreduction. The preparation of BC-AQDS in this study effectively improve the utilization of quinone compounds and offer a promising approach for enhancing the bioreduction of Cr(VI). It provides a more comprehensive reference for understanding and solving the problem of Cr pollution in groundwater.

Effects of Different pH Levels on the Structural and Functional Properties of Proteins of Phaeodactylum tricornutum.

Phaeodactylum tricornutum is identified by its capacity for rapid growth, reproduction, and in vitro cultivation, as well as the presence of a range of high-value active compounds, including proteins, with potential food applications. The objective of this study was to investigate the effects of pH shift treatments (pH of 3, 5, 7, 9, and 11) on the structural and functional properties of the Phaeodactylum tricornutum protein (PTP). The molecular weight of the PTP was predominantly distributed within the following ranges: below 5 kDa, 5-100 kDa, and above 100 kDa. Compared to the acidic environment, the PTP demonstrated higher solubility and greater free sulfhydryl group content in the alkaline environment. Additionally, PTP had a smaller particle size and higher thermal stability in alkaline environments. The PTP exhibited superior foaming ability (135%), emulsification activity index (3.72 m2/g), and emulsion stability index (137.71 min) in alkaline environments. The results of this investigation provide a foundation for the future development and application of the PTP in the food industry.

Fabricating a high-loading smart film to monitor pork freshness via adsorption of anthocyanins on simultaneously etched, anionized and bleached wood cell wall

In this paper, wood cell walls were simultaneously roughened, carboxylated, and bleached via NaOH/H2O2 treatment and roughened-poplar film (RPF) was obtained. Compared with the untreated film, the carboxyl group content increased 8 times to 1.92 mmol/g, and the pore growth rate reached 11.24%. Afterwards, a pH-indicator wood film (CTA-RPF) was prepared by self-adsorption of anthocyanins on RPF. It rapidly changed from purple to green within 7 s in 0.25 mL of ammonia at 53% RH and the initial color could restore in the air. When anthocyanins adsorption capacity reached 1.95 mg/g, only 0.36 cm2 of the film could accurately indicate the quality change of 300 g pork. Currently, CTA-RPF is the smallest smart film that can track the maximum mass of pork after comparing with other researches, therefore, promising to be used as a smart indicator label to track the freshness of pork in real market circulation.

Optimization of Cellulose Nanofibers and Castor Oil in the Synthesis of Starch-carrageenan-polyvinyl Alcohol Biothermoplastic Film

The improvement of the properties of starch, carrageenan, and polyvinyl alcohol (SCPVA) biothermoplastics film is necessary be used as packaging materials that comply with SNI 7818:2014 and international standards. The aim of this research is to optimize the concentration of cellulose nanofiber and castor oil in the synthesis of SCPVA bio-thermoplastic film; so that, the best characteristics are obtained and SNI 7818:2014 and international standards are met. Optimization was carried out using the Response Surface Methodology (RSM) application with the independent variable (input control variable) concentration of cellulose nanofiber and castor oil with the dependent variable (response variable) tensile strength, elongation at break, and Young Modulus. SCPVA bio-thermoplastic film with an optimal concentration of cellulose nanofiber and castor oil was observed for swelling, WVTR, surface profile, functional group content, thermal stability, and crystallinity by reviewing X-ray diffraction intensity. The research results showed that the optimum concentrations of cellulose nanofiber and castor oil in the synthesis of SCPVA biothermoplastic film are 6.05% and 0.96%, respectively. The tensile strength, elongation at break and Young's modulus values of the resulting optimum treatment are 37.21 MPa, 4.347% and 1041.86 MPa, respectively. Hence, with optimization, the SCPVA bio-thermoplastic film has the highest tensile strength and Young's modulus values but the lowest elongation at break values. The physical and mechanical characteristics of SCPVA bio-thermoplastic film have met SNI 7818:2014 and most of ASTM 5336, therefore, it can be used as packaging.

Preparation and properties of walnut cake-based wood adhesive with oxidation modification

Walnut cake has the potential for use in preparing wood adhesives because of its richness in protein and carbohydrate. In this work, walnut cakes were treated with sodium periodate or potassium permanganate and then were directly used as wood adhesives. Their bonding properties, curing performances, thermal properties, and chemical structures were compared. The results showed that: (1) The oxidation by KMnO4was non-selective. The reaction was very intense, accompanied by the great variability of oxidation degree and degradation degree, enormous viscosity of oxidation products, high coating difficulty, and low content of active aldehyde groups. (2) The oxidation by NaIO4 was selective; the reaction was mild and easy to control. More active aldehydes could be produced and the treatment was beneficial for constructing a spatial net structure of the adhesive. (3) Compared with oxidation of KMnO4, the walnut cake adhesive prepared by NaIO4 oxidation exhibited a more compact structure, a higher crosslinking degree, low curing temperature, and high thermal stability after curing; its bonding performances met the requirements for Class II plywood specified in GB/T 17657(2013).

Research on the Interaction Mechanisms between ScCO2 and Low-Rank/High-Rank Coal with the ReaxFF-MD Force Field.

CO2 geological sequestration in coal seams can be carried out to achieve the dual objectives of CO2 emission reduction and enhanced coalbed methane production, making it a highly promising carbon capture and storage technology. However, the injection of CO2 into coal reservoirs in the form of supercritical fluid (ScCO2) leads to complex physicochemical reactions with the coal seam, altering the properties of the coal reservoir and impacting the effectiveness of CO2 sequestration and methane production enhancement. In this paper, theoretical calculations based on ReaxFF-MD were conducted to study the interaction mechanism between ScCO2 and the macromolecular structures of both low-rank and high-rank coal, to address the limitations of experimental methods. The reaction of ScCO2 with low-rank coal and high-rank coal exhibited significant differences. At the swelling stage, the low-rank coal experienced a decrease in aromatic structure and aliphatic structure, and high-rank coal showed an increase in aromatic structure and a decrease in aliphatic structure, while the swelling phenomenon was more pronounced in high-rank coal. At the dissolution stage, low-rank coal was initially decomposed into two secondary molecular fragments, and then these recombined to form a new molecular structure; the aromatic structure increased and the aliphatic structure decreased. In contrast, high-rank coal showed the occurrence of stretches-breakage-movement-reconnection, a reduction in aromatic structure, and an increase in aliphatic structure. The primary reasons for these variations lie in the distinct molecular structure compositions and the properties of ScCO2, leading to different reaction pathways of the functional group and aromatic structure. The reaction pathways of functional groups and aromatic structures in coal can be summarized as follows: the breakage of the O-H bond in hydroxyl groups, the breakage of the C-OH bond in carboxyl groups, the transformation of aliphatic structures into smaller hydrocarbon compounds or the formation of long-chain alkenes, and various pathways involving the breakage, rearrangement, and recombination of aromatic structures. In low-rank coal, there is a higher abundance of oxygen-containing functional groups and aliphatic structures. The breakage of O-H and C-OH chemical bonds results in the formation of free radical ions, while some aliphatic structures detach to produce hydrocarbons. Additionally, some of these aliphatic structures combine with carbonyl groups and free radical ions to generate new aromatic structures. Conversely, in high-rank coal, a lower content of oxygen-containing functional groups and aliphatic structures, along with stronger intramolecular forces, results in fewer chemical bond breakages and makes it less conducive to the formation of new aromatic structures. These results elucidate the specific deformations of different chemical groups, offering a molecular-level understanding of the interaction between CO2 and coal.

Perspective of Islamic Law and Ulama Polemics about Women Judges (Gender Analysis and Moderation of Fiqh)

This study aims to investigate and debate the validity of women's opinions founded on the normative Islamic viewpoint known as fiqh. This research endeavor endeavors to scrutinize the arguments of various ulama, or Muslim scholars, concerning female judges while maintaining a foundation in fiqh, the body of Islamic law. This study's technique combines focus group discussions (FGD) and content analysis with qualitative approaches. FGD is held with numerous lecturers and specialists in Islamic law at the Faculty of Sharia and Law at Institut Agama Islam Negeri Syekh Nurjati Cirebon. The study's conclusions, which come from at least three well-known ulama or Muslim scholars, indicate that the debate among fiqh experts on the standing of women judges was affected by several factors.

Effects of bagasse as a carbon source on biofloc formation, water quality, and microbial community structure in shrimp culture system.

As a widely available, low-cost agricultural byproduct, bagasse is a potential solid carbon source and provides microbial attachment as a biofilm carrier. In this study, the effects of bagasse as a carbon source on biofloc formation, water quality, microbial community structure, and nitrogen conversion in a shrimp culture system were explored, and the performance of bagasse bioflocs was assessed. No bagasse was added to the control group (CK), and three bagasse addition groups were set up, with the floc content of the water maintained at 5 mL/L (BF5 group), 10 mL/L (BF10 group), and 15 mL/L (BF15 group). The results showed that bagasse bioflocs formed in the fourth week when bagasse was placed in the culture water, and the surface of bagasse was covered with thick biofilm at that time. The DOC content of the BF15 group was significantly greater than that of the CK group, from 30.31 to 105.06% (P < 0.05), and the DOC increased with increasing bagasse biofloc content. The BF group rapidly converted TAN to NO2--N and then to NO3--N because the accumulation of nitrite nitrogen in the BF15 group occurred 1 week earlier than in the other groups; at the 8th week, the nitrite nitrogen conversion rate of each BF group was close to 100%, which was significantly greater than that of the CK group (P < 0.05). The relative abundances of genes encoding microbial glutamate dehydrogenase and glutamate synthase increased in the bagasse biofloc groups (P < 0.05). The relative abundances of genes from Rhodobacterales and Hyphomicrobiales in each group were greater, but bagasse bioflocs increased the proportion of Hyphomicrobiale. In summary, adding bagasse to the shrimp culture system can form a biofloc system, resulting in the formation of a rich bacterial biofilm on its surface. Bagasse addition not only affects the composition of microbial communities but also accelerates the nitrification process in water. As a result, ammonia and nitrite are converted into nitrate, which is essential for maintaining the stability of the ecosystem balance in aquaculture water.

The Effect of Macromonomer Surfactant Microstructure on Aqueous Polymer Dispersion and Derived Polymer Film Properties.

Water-borne coatings were prepared from poly(methyl methacrylate-co-butyl acrylate) latexes using different methacrylic acid containing macromonomers as stabilizers, and their physical properties were determined. The amphiphilic methacrylic acid macromonomers containing methyl, butyl, or lauryl methacrylate as hydrophobic comonomers were synthesized via catalytic chain transfer polymerization to give stabilizers with varying architecture, composition, and molar mass. A range of latexes of virtually the same composition was prepared by keeping the content of methacrylic acid groups during the emulsion polymerization constant and by only varying the microstructure of the macromonomers. These latexes displayed a range of rheological behaviors: from highly viscous and shear thinning to low viscous and Newtonian. The contact angles of the resulting coatings ranged from very hydrophilic (<10°) to almost hydrophobic (88°), and differences in hardness, roughness, and water vapor sorption and permeability were found.

Investigating the Formation of In Vitro Immunogenic Gluten Peptides after Covalent Modification of Their Structure with Green Tea Phenolic Compounds under Alkaline Conditions.

Celiac disease is an autoimmune disorder triggered by immunogenic gluten peptides produced during gastrointestinal digestion. To prevent the production of immunogenic gluten peptides, the stimulation of covalent-type protein-polyphenol interactions may be promising. In this study, gluten interacted with green tea extract (GTE) at pH 9 to promote the covalent-type gluten-polyphenol interactions, and the number of immunogenic gluten peptides, 19-mer, 26-mer, and 33-mer, was monitored after in vitro digestion. Treatment of gluten with GTE provided an increased antioxidant capacity, decreased amino group content, and increased thermal properties. More importantly, there was a remarkable (up to 73%) elimination of immunogenic gluten peptide release after the treatment of gluten with 2% GTE at 50 °C and pH 9 for 2 h. All of these confirmed that gluten was efficiently modified by GTE polyphenols under the stated conditions. These findings are important in developing new strategies for the development of gluten-free or low-gluten food products with reduced immunogenicity.

Granular activated carbon supported polyethylene glycol modified nano-zero-valent iron immobilized microbial removal of 2,4-dichlorophenol in water

In recent years, the remediation of 2,4-DCP pollution using immobilized microbial technology has attracted increasing attention. Using granular activated carbon (GAC), polyethylene glycol 4000 (PEG-4000), ferrous sulfate, and sodium borohydride as raw materials, granular activated carbon loaded polyethylene glycol modified nano zero-valent iron composite material (PEG-nZVI/GAC) was prepared via a liquid-phase reduction method. Bacillus marisflavi, capable of degrading phenolic compounds, was immobilized on PEG-nZVI/GAC using an adsorption method to prepare immobilization of microorganisms by granular activated carbon loaded polyethylene glycol modified nano zero-valent iron (PEG-nZVI/GAC@B) for 2,4-DCP removal. Characterization analysis of immobilized microbes was conducted using transmission electron microscopy (TEM) and other methods to determine their physicochemical properties. Response surface methodology (RSM) was employed to optimize the conditions for 2,4-DCP removal, and the performance and mechanism of 2,4-DCP removal by PEG-nZVI/GAC@B were studied. The results indicate that nanoscale zero-valent iron (nZVI) was uniformly distributed in granular activated carbon, Bacillus marisflavi was successfully loaded onto PEG-nZVI/GAC, PEG-nZVI/GAC@B had a higher content of oxygen-containing groups on its surface, and exhibits good dispersibility, stability, and reusability. When the immobilized microbial dosage was 270.32 mg/L, the initial concentration of 2,4-DCP was 50.51 mg/L, and pH was 6.58, the predicted removal rate of 2,4-DCP was 96.53 %. Under these conditions, the actual removal rate of 2,4-DCP was 94.68 %. The removal of 2,4-DCP by PEG-nZVI/GAC@B involved adsorption by granular activated carbon, reductive dechlorination by nanoscale zero-valent iron, and degradation by Bacillus marisflavi. In conclusion, PEG-nZVI/GAC@B is an excellent immobilized microorganism for the removal of 2,4-DCP.

Self-heating photothermal synergistic catalytic decomposition of carcinogenic formaldehyde by α-MnO2 at ambient temperature: Functional roles of surface acidic-basic sites

Formaldehyde is a major pollutant in indoor atmosphere, and the realization of complete mineralization of formaldehyde at room temperature is of great significance and practical demand for improving indoor air quality. Surface acidic-basic sites, as one of the important surface properties that have significant influence on catalytic oxidation of formaldehyde, revealing their functions is beneficial for the development of efficient formaldehyde decomposition materials. Herein, the α-MnO2 acidic-basic sites were regulated and its effects on self-heating photothermal catalytic oxidation of formaldehyde were further contrastive investigated. The acidic-basic sites showed distinct functions: the basic sites exhibited a significant promotion on formaldehyde oxidation; While the acidic sites greatly inhibited the reactivity. Particularly, the basicity enhanced α-MnO2 could reach the 100% conversion of formaldehyde at ambient temperature. Furthermore, the self-heating photothermal mechanism was consonant with the thermal-assisted photocatalysis mechanism, rather than traditional photo-drive thermal catalysis mechanism. The strength of basic sites significantly increased the content of surface hydroxyl groups, and the electron-rich basic sites were favorable for the activation of oxygen, thereby generating more reactive oxygen species for the decomposition of formaldehyde. Moreover, in-situ DRIFTS reveals that the enhancement of basic sites can accelerate the rate oxidation of HCHO to generate formates and carbonates. This work clarified the influence of surface acid-base properties on formaldehyde photothermal decomposition.

Structural and functional properties of ozone-treated quinoa starch

Ozone is a very powerful oxidizing agent and can rapidly decompose without generating waste. Ozone was applied to oxidize quinoa starch suspensions (10 g/100 g) were subjected to oxidation by ozonization and the effect of ozone generation time (OGT: 10, 20 and 30 min) was investigated on their structural and functional properties. As OGT increased from 10 to 30 min, amylose content and relative crystallinity reduced. Gel-permeation chromatography analysis indicated amylose depolymerization and structural analysis by FTIR revealed that ozonized starches had a considerable reduction in the degree of crystallinity with increasing OGT. Carbonyl/carboxyl group contents, paste clarity (26 %), oil absorption capacity (23 %) and peak apparent viscosity, values increased significantly (p ≤ 0.05) for treated samples. Ozone increased the mean diameter (D [2,3]), the onset temperature (DSC), and pasting properties. Thus, ozonization is a powerful method to modify starch, as well as a safe and inexpensive oxidizing process.

Effect of side group modification on the glass transition and adhesion properties of polysiloxane at the atomic scale

Polysiloxane is a typical biomimetic dry adhesive, and polysiloxane-silica interface is a typical interface widely existing in test systems and wall-climbing robots. Studying the glass transition temperature (Tg) of polysiloxane and its adhesion properties on silica surfaces has important theoretical guiding significance and practical value for developing and applying a new generation of dry adhesion functional surfaces and devices. However, the effect of the type and content of side groups on the Tg and adhesion properties of polysiloxane is still unclear. Therefore, three side group combinations are included in the established modified polysiloxane models, with each type corresponding to five different side group contents. Molecular dynamics (MD) is used to investigate the effect of side group modification on the Tg of polysiloxane and the adhesion properties on the silica surface. The results show that, compared with polydimethylsiloxane (PDMS), introducing phenylmethyl or diphenyl into the polysiloxane increases the Tg in the studied range of side group contents. The introduction of diethyl decreases the Tg. The corresponding interfacial interactions are enhanced when the diethyl content is 2%, 4% and 10%, the phenylmethyl content is 4%-10% and the diphenyl content is 2%-10%. The interfacial interactions are weakened at the unmentioned side group content. The ratio of van der Waals energy to the interfacial interaction energy is above 94.5% in all interfaces, which means that van der Waals interaction dominates the interaction between polysiloxane and silica surface. The present model provides a deeper insight into polysiloxane, which may contribute to designing future bioinspired dry adhesives.

Fossil metasomatized and newly-accreted fertile lithospheric mantle volumes beneath the Bakony-Balaton Highland Volcanic Field (central Carpathian-Pannonian region)

This study focuses on upper mantle xenoliths from Sabar-hill (Bakony-Balaton Highland Volcanic Field), a newly discovered locality of mantle xenoliths, situated in the central Carpathian-Pannonian region (CPR). The investigated seven peridotite and one pyroxenite xenoliths record two episodes in the geochemical evolution of the local subcontinental lithospheric mantle. The moderately deformed Group I xenoliths reveal modal contents (≥9 vol% orthopyroxene), major element characteristics (depletion in Al2O3 and CaO in orthopyroxenes) and trace element features (e.g., enrichment in U, Pb and Sr in clinopyroxenes) typical in supra-subduction zones (i.e., mantle wedge) xenoliths. All these suggest that the studied xenoliths were formed by silica-rich fluid/melt - peridotitic wall rock interactions. The tectonic background to the formation of Group I xenoliths is likely linked to the subduction of an oceanic slab during the Mesozoic-Paleogene. This may have happened far from the current position of Sabar-hill, to where the lithosphere, including the metasomatized mantle volume, was transferred via plate extrusion. The less deformed, dominantly protogranular and porphyroclastic Group II xenoliths are depleted in light rare earth elements (LREE). In contrast, they are enriched in clinopyroxene (≥11 vol%), incompatible major elements (e.g., Al and Na) and heavy rare earth elements (HREE), by a minimum of four times compared to primitive mantle. All these suggest that Group II xenoliths represent a geochemically fertile mantle partition and the degree of partial melting affected this mantle section was limited (≤7% based on trace elements). Group II xenoliths have higher equilibrium temperatures (1088–1168 °C) compared to Group I xenoliths (1018–1089 °C). The lack of petrographic and geochemical evidence pointing to metasomatism-related annealing in Group II xenoliths suggests that they are derived from a greater depth. It follows that Group II xenoliths could represent prior asthenosphere volumes which recently accreted to the lithosphere. The lithospherization of the upper part of the asthenosphere may have initiated after the tectonic inversion of the region, when compressional tectonic regime beneath the CPR gradually overtook the former extensional one in the last ~8 Ma. The high bulk structural hydroxyl content in both Group I (22–1699 ppm) and II (55–320 ppm) xenoliths is likely linked to the subduction events that took place in the CPR from the Mesozoic onwards. These events transported significant amounts of fluid (H2O) back to the upper mantle, affecting both the mantle wedge and the asthenosphere.

Fast reversion of hydrophility-superhydrophobicity on textured metal surface by electron beam irradiation

Reversible hydrophilic-hydrophobic transitions on metal surfaces are challenging in surface-wetting treatment. Existing preparation methods have the disadvantages of requiring a long time, producing a metal oxide layer, and being difficult to implement. In this paper, a rapid reversible transitions between hydrophilicity and superhydrophobicity was achieved on the surface of 316L stainless steel using laser etching combined with electron beam irradiation. The contents of C–C/C–H hydrophobic functional groups was found to be notably increased by low electron dose in the experiments. The contents of C-O-C, O-C = O and –OH hydrophilic functional groups decreased. The interaction of excited secondary electrons with precursor molecules generated free radical fragments that adsorbed onto surfaces and formed new chemical bonds, changing the content of the functional groups. Reversible hydrophilic and superhydrophobic transitions could be achieved by adjusting the electron dose. The contact angle continually changed from 91° to 160° with a beam current of 100 μA, to 17° with 300 μA, and back to 90° with cleaning. The entire procedure required only four minutes. Meanwhile, the superhydrophobic state with contact angle of 160° has a sliding angle of 6°, presenting excellent resistance to bacterial adhesion, UV irradiation, and delayed icing.