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This study aimed to establish the optimal production conditions for mealworm chitosan oligosaccharides (MCOS) using the response surface methodology and measure the prebiotic effect of MCOS prepared on cecal microbiota through in vitro anaerobic fermentation. The optimal conditions for MCOS production using chitosanase were 2.5% substrate, 30 mg/g enzyme, and 6 h reaction time. Matrix-assisted laser desorption ionization-time of flight mass spectrometry, Fourier transform infrared spectroscopy, and in vitro assays to confirm that the chemical structure and physicochemical properties of MCOS are similar to those of commercially available chitosan oligosaccharides. The growth of Lactobacillus acidophilus, Lacticaseibacillus casei, and Bifidobacterium bifidum was increased by MOCS and confirmed that the prebiotic effect of MCOS was significant in a concentration-dependent manner. The addition of 1% and 2% MCOS to in vitro anaerobic fermentation resulted in changes in the content of short-chain fatty acids (SCFAs) and an increase in Verrucomicrobiota abundance compared with the control. In the case of Romboutsia, Turicibacter, and Akkermansia, a significant increase was confirmed in the MCOS-containing groups compared to that in the control group. Compared to 2% MCOS, 1% MCOS more significantly affected Lactobacillus levels. MCOS produced by chitosanase under optimal conditions contains oligosaccharides with 2–6 degree of polymerization and exerts a prebiotic effect that affects changes in the SCFA content and microbiota composition in the cecum. [ABSTRACT FROM AUTHOR]

It is very important and challenging to efficiently and eco-friendly recycle the waste cotton textiles, especially for the dyed cotton-polyester blended textiles due to their complex dye composition and recovery of cotton components from them. Here, we proposed a recycling route for waste dark-colored cotton-polyester denim fabrics containing sulphur dyes, involving decolorization, alkali cooking for pulp and bleaching. Thiourea dioxide (TDO) was utilized as a reducing agent to remove the sulphur dyes of the fabrics in NaOH solution system, and the effects of TDO dosage, temperature and time on decoloring efficiency were discussed. Alkali cooking with hydrogen peroxide was used to prepare cellulose pulp and remove polyester fiber components simultaneously. Then the prepared pulp was bleached through the hydrogen peroxide/tetraacetylethylenediamine to further improve its whiteness. The dissolving pulp obtained from the dark-blue and black denim fabrics had the CIE whiteness indices of 89 and 65, and the degrees of polymerization of 522 and 565, respectively. This study provided a new approach for the recycling and reuse of waste cotton textiles. [ABSTRACT FROM AUTHOR]

Obesity presents a significant public health challenge, demanding effective dietary interventions. This study employed a high-fat diet-induced obesity mouse model to explore the impacts of inulin with different polymerization degrees on obesity management. Our analysis reveals that high-degree polymerization inulin (HDI) exhibited a significantly higher oil binding capacity and smaller particle size compared to low-degree polymerization inulin (LDI) (p  <  0.05). HDI was more effective than LDI in mitigating body weight gain in high-diet induced obese mice, although neither LDI nor HDI affected blood sugar levels when compared to the high-fat diet control group (p  <  0.05). Both HDI and LDI administrations reduced liver weight and enhanced brown adipose tissue thermogenesis compared to the high-fat diet induced control group (p  <  0.05). Additionally, HDI suppressed hepatic lipogenesis, resulting in a further reduction in liver triglycerides compared to the high-fat diet-induced obese mice (p  <  0.05). Notably, HDI improved gut health by enhancing intestinal morphology and modulating gut microbiota structure. HDI administration notably increased the relative abundance of cecal Akkermansia, a gut microbe associated with improved metabolic health, while LDI showed limited efficacy (p  <  0.05 and p  >  0.05, respectively). These findings underscore the importance of the structural properties of inulin in its potential to combat obesity and highlight the strategic use of inulin with varying polymerization degrees as a promising dietary approach for obesity management, particularly in its influence on gut microbiota composition and hepatic lipid metabolism regulation. [ABSTRACT FROM AUTHOR]

The first rare-earth borate crystal CsBa2 ScB8 O16 with both zero-dimensional [B3 O6] units and one-dimensional B--O chain structures has been synthesized by the high-temperature solution method. It crystallizes in the triclinic crystal system with the P1 space group, with lattice parameters of a =6.698 5 Å, b =7.216 Å, c =14.798 Å, α =97.563°, β =95.226°, γ = 95. 546°, Z = 2. In this compound, [BO3] and [B4 O9] units are connected by sharing oxygen atoms to form a onedimensional chain [B5 O10]∞. Octahedrally coordinated [Sc(1)O6] groups and the one-dimensional chain [B5 O10]∞ are further connected by sharing oxygen atoms to form two-dimensional layer [Sc(1) (B4 O9)]∞. Interlayers are linked by octahedrally coordinated [Sc(2)O6] groups, which share oxygen atoms to form a three-dimensional Sc--B--O framework. Isolated [B3 O6] units are filled in the three-dimensional channels with Cs+ and Ba2 + to balance the charges. In order to further explore the novelty of the structure of CsBa2 ScB8 O16, we compared it with other rare-earth borates containing alkali or alkaline-earth metals, and discuss the effect of the cation-to-boron molar ratio (n(A) / n(B)) on the degree of polymerization of B--O units, as well as the dimensionality of the B--O anion framework. Furthermore, the first-principles calculations, infrared spectrum, UV-vis-NIR diffuse reflectance spectrum and the thermal analysis of the compounds have also been performed. Property measurements show that CsBa2 ScB8 O16 exhibits short UV absorption edge (< 190 nm) and moderate birefringence (0. 072@1 064 nm). The optical properties of the compound are mainly contributed by the [B3 O6], [B5 O10] units, and [ScO6] octahedra. [ABSTRACT FROM AUTHOR]

The present work evaluates starch from 29 diverse pea accessions for structural (amylose content and amylopectin chain length distribution), granule size distribution, thermal, pasting, and retrogradation properties. Amylose content and the proportion of amylopectin chains with the degree of polymerization (DP) of 6–10, 11–20, and >20 vary in the range from 21.4% to 57.0%, 17.9% to 25.8%, 64.0% to 66.5%, and 9.4% to 16.7%, respectively. Starches with a higher proportion of small granules (<5 µm) have a greater proportion of amylopectin chains with DP > 10 and exhibit higher transition temperatures/enthalpy and vice versa. Retrogradation in starch pastes relates negatively to the proportion of amylopectin chains with DP < 10. Paste viscosities relate negatively with amylopectin chains with DP > 10, amylose content, and retrogradation while positively with transition temperatures/enthalpy and the potential of granules to swell. [ABSTRACT FROM AUTHOR]

The oxidation property of liquid-phase sintered silicon carbide (LPS-SiC) ceramics with ZrB 2 addition was studied after oxidation test in air at 1400 °C. The results indicate that the addition of ZrB 2 decreased the degree of polymerization (DOP) of the silicate networks in the oxide layer, suppressing the additional oxidation caused by residual bubbles in the oxide layer of LPS-SiC, which bypassed the layer and directly corroded the material internally. After 100 h of oxidation, the additional oxidation depth was found to be 125 μm in the sample without ZrB 2 and 0 μm in those containing 10 wt% ZrB 2. Simultaneously, the decrease in DOP facilitates the migration of crystalline phases. The generated ZrSiO 4 can migrate and aggregate at the interface between the surface oxide layer and the SiC/ZrB 2 matrix, forming a continuous ZrSiO 4 barrier. This impedes the diffusion of the oxidant and enhances the oxidation resistance. However, an insufficient ZrB 2 content leads to a discontinuous ZrSiO 4 layer, thereby weakening its protective effect. Simultaneously, a decrease in DOP increases the rate of oxygen diffusion, resulting in an increase in the oxidation layer thickness. This study contributes to a better understanding of the failure mechanisms of LPS-SiC in oxidizing environments and provide a reference for the design of oxidation-resistant LPS-SiC materials. [ABSTRACT FROM AUTHOR]

The formation of cross-linked enzyme aggregates (CLEAs) using macromolecular cross-linkers improves substrate accessibility and enhances enzyme retention. However, there have been few studies exploring the use of macromolecular cross-linkers due to the challenges related to cross-linker screening. In compliance with our previous computational and experimental screening, dextran is the optimal macromolecular cross-linker to develop CLEAs of endolevanase from Bacillus lehensis G1 (rlevblg1-dex-CLEA) for levan-type-fructooligosaccharides (L-FOS) production. In this study, rlevblg1-dex-CLEAs was optimized, and the activity recovery continued to increase and reached 90.5%. Subsequently, the rlevblg1-dex-CLEAs were characterized and they displayed higher thermal stability after 1 h of incubation in comparison to the free enzyme. Moreover, the rlevblg1-dex-CLEAs were reusable for five cycles and exhibited greater storage stability over 180 days at 4 °C (60.9%) than that of free rlevblg1. In addition, the rlevblg1-dex-CLEAs demonstrated similar catalytic efficiency as the free enzyme and generated a substantial amount of L-FOS with a longer degree of polymerization, which is more beneficial for industrial use. [ABSTRACT FROM AUTHOR]

Alkali-activated materials (AAMs), which are prepared by using various solid wastes as precursors and reacting with alkaline solutions, are gradually applied in the construction industry. However, not all solid waste precursors can exhibit good performance in the preparation of AAMs. To realize the effective utilization of phosphorus slag (PS) solid waste, alkali-activated PS-GBFS-FA (AAPGF) was prepared by using PS and GBFS/FA. Using different contents of GBFS/FA to replace PS, the workability performance, mechanical properties and hydration products of AAPGF were investigated. The incorporation of GBFS/FA improves the fluidity of AAPGF, but leads to slurry flash setting. When containing 30% GBFS/FA, the 28 days compressive strength of AAPGF can reach the highest 72.65 MPa. GBFS/FA increased the number of C-(A)-S-H gels, accompanied by the formation of hydrotalcite gels. In addition, GBFS/FA also transforms AAPGF hydration products from C-S-H gel to C-(N)-A-S-H and N-A-S-H gel with high degree of polymerization, and SiO4 tetrahedron is Q2 unit. GBFS/FA will significantly reduce unhydrated particles, but it will lead to uneven distribution of hydration products and produce large pores. The results of this study can provide reference value for the effective use of PS. [ABSTRACT FROM AUTHOR]

The influence of TiO2 and CaO/Al2O3 on the surface tension of CaF2–CaO–Al2O3–SiO2–MgO–TiO2 low‐fluorine slag system is determined by pulling method, and the melting characteristics of the slag system are determined by differential scanning calorimetry. It is found that the surface tension decreases with the increase of temperature. With the increase of TiO2 from 7% to 16%, the surface tension decreases from 2.97 to 0.71 N m−1, the Tend decreases from 1683 to 1648 K, and the activation energy decreases gradually. When the CaO/Al2O3 increases from 0.9 to 1.8, both the surface tension and Tonset show a minimum value, the surface tension is 2.286 N m−1, the Tonset is 1498 K, and the crystallization phase is formed during the melting process. The main reason TiO2 affects the structure is the substitution of Ti4+ for Al3+ in the [AlO4]5− structure to form the Ti2O64− structure, which leads to depolymerization of the Q2 and Q3 polymerization degree and thus the slag system structure, while CaO/Al2O3 affects the slag polymerization degree by influencing the amount of bridging oxygen. Finally, the surface tension is characterized using each structure to derive a relationship between structure and surface tension. [ABSTRACT FROM AUTHOR]

In this study, we synthesized eight palladium‐based catalysts using two carriers, ZrO2 and MCM‐41. These catalysts were used for the degradation of condensed tannins extracted from larch bark. The average polymerization degree and degradation rate of the products were used as indicators to evaluate the efficiency of degradation. The effects of different Pd:Cu loading ratios under the same carrier conditions and the effects of different carriers under the same Pd:Cu loading ratio were investigated. The results revealed that when the carrier was kept constant, the Pd:Cu ratio of 1:1 exhibited the highest efficiency in degrading condensed tannins. Moreover, when the Pd:Cu loading ratio was the same, the degradation efficiency was higher when ZrO2 was used as the carrier. Based on these findings, the catalyst (Pd1‐Cu1)5/ZrO2 (where "1" are the molar ratios of Pd to Cu added during the preparation of the catalyst and where '5' is the mass percentage of Pd/Cu metal to total catalyst, i.e., 5 wt%), with ZrO2 as the carrier and a Pd:Cu ratio of 1:1, demonstrated the highest degradation efficiency, with a degradation rate of 73.89%. This catalyst successfully reduced the average polymerization degree of condensed tannins from 9.5 to 2.48. [ABSTRACT FROM AUTHOR]

The isotopic fractionation of carbon between CO 2 gas and silicate melts is a crucial parameter to understand the carbon cycle at the planetary scale that requires accurate quantification. In this study, we conducted experiments to determine the carbon isotope fractionation between CO 2 gas and carbon dissolved in silicate melt at 350 – 420 MPa and 1160 – 1225 °C, across a range of melt compositions. A linear relationship emerges between the fractionation coefficient and the degree of polymerization of the melt (NBO/T; non–bridging oxygens per tetrahedral cation) with the fractionation coefficient increasing for depolymerized melts (e.g., basalt) and decreasing for polymerized melts (e.g., rhyolite): 1000 ln α gas - m e l t = 3.251 × N B O / T + 0.026 R 2 = 0.74 or 1000 ln α gas - m e l t = - 0.087 × Si O 2 + A l 2 O 3 w t % + 7.968 R 2 = 0.74 . These equations enable the calculation of carbon fractionation coefficients in silicate melts, providing a mean to interpret δ13C–value measurements in natural volcanic gases and melts through forward and backward modelling of degassing paths from mantle to surface. We hypothesize that the ratio of CO 3 2–/CO 2 dissolved in the melt is the key parameter behind this relationship. Carbon dissolved as CO 2 molecular transfers to the gas phase with a fractionation coefficient of 0 ‰ whilst carbon dissolved as CO 3 2– transfers with a fractionation coefficient of 2.9 ‰. The relationship is calibrated from NBO/T=0 to 0.88, covering most major melt compositions. However, at NBO/T>0.88, as the CO 3 2–/CO 2 ratio reaches its maximum in silicate melt, correspondingly the fractionation coefficient reaches its maximum of 2.9 ‰, both are expected to stabilize and remain constant. Carbon isotopic fractionation might hence offer a window into carbon speciation in natural melts. [ABSTRACT FROM AUTHOR]

Eucalyptus branches and bark represent highly abundant and available feedstocks with great potential for obtaining bio-based products. Distinct and integrated pretreatment fractionation strategies for eucalyptus branches and bark were performed for the efficient production of xylooligosaccharides (XOS). By combining pretreatments, a high yield of XOS was obtained from eucalyptus branches and bark. The branches and bark were presoaked in 8% (w/w) sodium hydroxide at 60 °C for 30 min to provide a deacetylation effect. The residues were then hydrothermally treated. The findings revealed that 4.64% of XOS originated from the bark and 6.19% from eucalyptus branches. It has been demonstrated that xylan may be selectively depolymerized during pretreatment by preventing excessive hydrolysis through the use of deacetylation in the first phase of the process. More XOS was produced using hydrothermal treatment, yielding 8.00% (w/w) in the branches and 5.12% in the bark. A significant amount of XOS with DP 2–5 might be obtained in certain experiments, up to 60%, but the most abundant XOS are usually those with DP > 5 (approximately 80% of all XOS). This work provides new insights into the effective generation of XOS under relatively mild conditions by overcoming the recalcitrant structure of eucalyptus branches and bark, representing a noteworthy advancement towards forestry leftover valorization. [ABSTRACT FROM AUTHOR]

The objectives of this study were to evaluate the bonding durability of four different self-etch adhesives to dentin after 24 h and thermal cycling (TC) and to measure the degree of polymerization conversion (DC) in situ. Two-step self-etch adhesives, Clearfil SE Bond 2 (SE2, Kuraray Noritake Dental) and G2-Bond Universal (G2B, GC), and one-step self-etch adhesives, Scotchbond™ Universal Plus Adhesive (SBU, 3M ESPE) and Clearfil Universal Bond Quick (UBQ, Kuraray Noritake Dental), were used. The labial surfaces of bovine teeth were ground to create flat dentin surfaces. The adhesives were applied according to the manufacturers' instructions. After resin composite buildup and 24 h water storage, the specimens were sectioned into beams and all groups were subjected to thermal stress for 0, 10,000 (10k), or 20,000 (20k) cycles followed by micro-tensile bond strength (µTBS) testing. In situ DC was investigated with a laser Raman microscope. The µTBS data were statistically analyzed and subjected to a Weibull analysis. The different groups were compared at the characteristic strength (63.2% probability of failure) (α = 0.05). Two-Way ANOVA was used to show the effect of different adhesives and thermal cycling on the mean DC% followed by Tukey's multiple comparison post hoc test. G2B/TC10k resulted in a significant increase in the µTBS compared to TC0. SBU/TC20k showed significantly higher µTBS compared to TC0. For comparison between different tested adhesives, SBU showed a significantly lower µTBS compared to G2B after TC10k. G2B and SBU showed a greater number of adhesive failures after TC. Mean DC% was different for each adhesive. The newly developed MDP- and HEMA-free 2-SEA showed similar bonding performance with the gold-standard 2-SEA. However, there is still room for further improvement in terms of SEAs. [ABSTRACT FROM AUTHOR]

The components synergistic affect the structure formation and complexity of anionic polymerization of blast furnace slag directly. The structure evolution of silicate polymerization with different i?2, to(MgO)/to( AI2O3 ) and to(Al2O3) changes was studied in this paper,thermodynamic calculation was used to determine the temperature rise regime and node for interrupting of the experiment. According to Raman spectrum analysis, it was found that when R2 and 00 (MgO)/oj( AI2O3 ) increased, the silicate anion groups in the blast furnace slag depolymerization occurred, and the structural units from Q4, Q3 to Qo, Qi and Q2 evolved, resulting in the deterioration of structural stability and the enhancement of slag fluidity. When the alkalinity is greater than 1. 2,ftj(MgO)/ftj(Al2O3) is greater than 0. 55, there is a reverse transformation or slowing trend. With the increase of ftj(Al2O3),it can be seen that the relative content of Qo changes little, the relative content of Qi increases first and then decreases, the relative content of Q2 decreases significantly,the relative content of Q3 increases significantly,the overall relative content of Q4 shows an increasing trends,the slag cluster structure tends to be complex,and the non-bridge oxygen content in the slag system shows a slow decreasing trend. When the content of to(Al2O3) exceeds 16%,the downward trend is more obvious. [ABSTRACT FROM AUTHOR]

The study aimed to assess the impact of diphenyliodonium hexafluorophosphate (DPI) on the physicochemical properties of experimental resin composites (ECRs) featuring reduced concentrations of camphorquinone (CQ)/amine. Five concentrations of CQ (0.125, 0.25, 0.5, 0.75, and 1 mol%) with dimethylaminoethyl amine benzoate (EDAB) in a 1:2 mol% ratio (CQ:EDAB) were incorporated into a 50:50 mass% monomer blend of bisphenol glycidyl methacrylate (BisGMA) and triethyleneglycol dimethacrylate (TEGDMA). An additional 5 groups with the same CQ:EDAB concentrations had 0.5 mol% DPI added. Each resin group contained 60 wt% of 0.7 µm barium-alumino-silicate glass. Light transmission (n = 3), real-time degree of polymerization (n = 3), temperature change during polymerization (n = 5), polymerization shrinkage strain (n = 3), flexural strength, and modulus (n = 12), as well as water sorption and solubility (n = 5), were evaluated. Data were analyzed using two-way ANOVA and Tukey's post-hoc test (α = 0.05). Light transmission was reduced in groups containing 0.125 and 0.25 mol% of CQ without DPI. DPI increased temperature, degree and rate of polymerization, despite the reduction in CQ/amine concentration. Additionally, there was an increase in polymerization shrinkage strain, flexural strength and modulus, and a reduction in water sorption and solubility in ECRs with DPI, even with lower concentrations of CQ/EDAB. DPI improved the assessed properties of composites across various concentrations of CQ/EDAB, showing the benefit of reducing the quantity of CQ used without compromising the properties and curing of the resin composites. [ABSTRACT FROM AUTHOR]

Coconut fibers contain many lignocellulosic components; therefore, they have the potential to be used as cellulose‐based materials. This study aims to synthesize carboxymethyl cellulose (CMC) for bioplastic applications from coconut fiber cellulose obtained from South Tangerang, Indonesia. The isolation of cellulose was conducted in two key stages: alkaline treatment using a delignification reactor and bleaching with hydrogen peroxide (H2O2). The facile synthesis of CMC involved two important steps: alkaline treatment and carboxymethylation of isolated cellulose. The yield of cellulose isolated from coconut fiber was 16.39% for biomass and 64.84% for delignification products. The cellulose produced exhibited a crystallinity index (C.I.) of 89%. The yield of CMC was 14.67%, with a C.I. was 56.66%. The CMC obtained was categorized as having a medium molecular weight of 249,048 Da with a polymerization degree of 1046. Cellulose starts to decompose at a temperature interval of 292.05–381.45°C, whereas CMC decomposes at a lower temperature interval of 245.42–299.73°C. Thermochemical calculations were conducted by using the density functional theory (DFT), confirming a spontaneous reaction with a Gibbs free energy of −5.25 kJ mol−1. Bioplastics were fabricated in two stages: blending with carboxymethyl chitosan (CMChi) and plasticizing with glycerol. The addition of CMCh increased the C.I. and tensile strength, while the addition of glycerol to CMC/CMChi (80/20) blend‐based bioplastic reduced the C.I. and tensile strength, but enhanced the relative contact angle. Highlights: Cellulose was isolated from coconut fibers through a two‐stage process involving delignification and bleaching;Carboxymethyl cellulose was synthesized by reacting the cellulose of coconut fibers with monochloroacetic acid in isopropanol with NaOH as the catayst;The optimum condition for achieving the highest elongation at break among the blending compositions was found in the CMC/CMChi (80/20) blend bioplastic;Adding up to 30 wt% glycerol decreased the tensile strength and increased the elongation at break;The addition of glycerol enhanced the hydrophobic properties of CMC/CMCh blend‐based bioplastics. [ABSTRACT FROM AUTHOR]

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

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

There are difficulties in measuring the molecular weight (Mw) of bacterial cellulose (BC) using Gel Permeation Chromatography (GPC) analysis. Additionally, the Mark-Houwink-Sakurada equation cannot be used to predict the Mw of BC as no Mark-Houwink-Sakurada constant specific to BC is available. In this study, a systematic approach is developed to establish the relationship between the Mw of BC and the viscosity of its copper (II) ethylenediamine (CED) solutions. Impurities contained in the raw BC are examined and appropriate purification procedures are designed for their removal before the above two measurements are conducted. The Mw of BC is obtained by measuring the Degree of Polymerization of its corresponding cellulose acetate (CA), derived from degraded BC, using GPC analysis, and the viscosity of the CED solutions of the BC is measured using a BS/U Tube viscometer. In this paper, the Mark–Houwink–Sakurada constants (K=0.3752 mL/g and α =1.4532) specific for BC are determined to relate the Mw of BC with the intrinsic viscosity of its CED solutions. It is also found that the Mw of BC is proportional to the dynamic viscosity (i.e., η BC = 0.0183 M w 1.3069 ) and the flow time (i.e., t BC = 1.3809 Mw 1.3062 ) of its CED solutions. These BC-specific relationships can help determine the Mw of BC from the rheological properties of its CED solutions. [ABSTRACT FROM AUTHOR]

Enhancing the degree of polymerization can mitigate the cytotoxic effects of resinous materials, as residual monomers have been identified as a significant contributor to cytotoxicity. Hence, the aim of the current research was to evaluate the influence of preheating self-adhesive cements at 39 °C on cell migration, cytotoxicity, and degree of conversion. RelyX U200, Set PP, and MaxCem Elite were subjected to Fourier Transform Infrared Spectroscopy–Attenuated Total Reflection (FTIR–ATR). Self-adhesive resin cements were applied onto an ATR device, with samples subjected to either heated or room temperature conditions, followed by photoactivation. For the cytotoxicity analysis, extracts (24 h and 7 days) were placed in contact with NIH/3T3 cells. For cell migration, images were captured of each sample until the possible closure of the cleft occurred. A two-way analysis of variance (ANOVA) was conducted to assess the effect of preheating on the degree of conversion and cell viability within the self-adhesive cements tested. A significance level of 5% was set for statistical purposes. In the results of the degree of conversion, preheating did not improve the conversion of cements (p > 0.05). For the 3-(4-5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT), preheating did not improve the results within 24 h, however, it generated positive results within 7 days for the Set PP resin cement (p < 0.05). For cell migration, high rates of cell death were found in all groups. It is concluded that preheating at 39 °C causes a positive effect only in increasing the cell viability of the Set PP resin cement and that both materials analyzed are highly cytotoxic. [ABSTRACT FROM AUTHOR]

An alkali-soluble β-glucan (AHEP-A-b, 20 kDa) purified from Hericium erinaceus fruiting bodies, was structurally characterized and examined for antioxidant activity. Methylation analysis and NMR spectroscopy show that the backbone of AHEP-A-b is composed of (1→6)-linked-D-β-glucopyran residues, branched at O-3 of glucopyranose (Glcp) residues with [→3)-β-D-Glcp-(1→] oligosaccharides or single unit of β-Glcp. Periodate oxidation analysis and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) indicate that the degree of polymerization (DP) of [→3)-β-D-Glcp-(1→] side chains is 2 to 8. Functionally, AHEP-A-b is a relatively strong antioxidant as demonstrated by using 2, 2′-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) free radical (ABTS·+), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, and hydroxyl radicals scavenging assays. The present study lays the foundation for further studies into structure-activity relationships of polysaccharides from H. erinaceus. [ABSTRACT FROM AUTHOR]

In Older to solve the problem of low quality and unstable source of dissolving pulp for domestic lyocell fiber, Russian space was used as raw material and high-quality dissolving pulp was prepared for lyocell fiber by pre-hydrolyzed sulfate cooking process. The effects of pre-hydrolysis, sulfate cooking, chlorine dioxide-hydrogen peroxide bleaching and acid treatment on the key technical indexes of dissolved pulp, such as α-cellulose content, polymerization, whiteness, ash content and metal ion content, were investigated. The experimental results show that the holding time of 90 min, the temperature of 150 °C and the solid-liquid ratio of 1:4 were the optimal prehydrolysis conditions, and the alkali content of 24%, the degree of vulcanization of 30% and the holding time of 180 min were the optimal cooking conditions. The slurry prepared under the optimal prehydrolysis and cooking conditions was treated with 1.5% chlorine dioxide bleaching, 12% cold alkali extraction, 5% hydrogen peroxide bleaching and 6% acetic acid, and the resulting pulp had a α-cellulose content, a whiteness of 85%, a polymerization degree of 647, an ash content of 0.06%, an iron ion content of 6 mg/kg, and a copper ion content of 3 mg/kg. Polarizing microscopy showed that the slurry could be completely dissolved in NMMO (moisture content of 13.3%) at 90 °c for 30 s. [ABSTRACT FROM AUTHOR]

Chokeberries, which belong to the rose family (Rosaceae), have received increasing research attention due to their high content of secondary metabolites, especially oligomeric proanthocyanidins (OPCs). OPC-rich extracts are attributed to various positive health effects, including antioxidant or anti-inflammatory properties, which is why they are sold as food supplements. However, knowledge about the antioxidant properties of single OPCs is quite limited. Several separation steps with different separation techniques were performed to isolate OPCs from a pre-produced extract. More than 90 analytes were detected in the enriched fractions, which include eight OPCs, four cinchonains and one hexoside, including their respective isomers. For the characterization of the OPCs, high-resolution mass spectrometry coupled with liquid chromatography (LC-HRMS) was used. Based on the fragment spectra of the MS2 experiments, conclusions about the fragmentation pathways and the structure of six new OPCs could be drawn. After isolating trimers, tetramers and pentamers, it was possible to test the antioxidant effect in relation to the individual degrees of polymerization (DP) or structures. The Trolox-equivalent antioxidant capacity (TEAC) test showed that all OPCs investigated exhibit antioxidant effects and a first correlation between the antioxidant effect and the DP could be postulated, which suggests new possibilities for the design of food supplements. [ABSTRACT FROM AUTHOR]

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

In this study, kitchen waste which is otherwise discarded or allowed to putrefy and pose environmental discomfort is co-composted with biochar to assess the effects of the biochar on the composting of kitchen waste as well as the quality of the final compost. To achieve this, biochar was composted with kitchen waste (w/w) in ratios of 10%, 20%, 30%, and 40% to determine its effect on composting process and the final compost product compared to cow dung-fortified kitchen waste as a control. Results indicate that pH and EC were not affected by biochar content during composting; however, biochar content had a profound effect on the attainment of thermophilic temperatures during composting, nitrification and other maturity/stability indexes such as germination index (GI), humification index (HI), degree of polymerization (DP) and HA/FA ratio. In effect, higher biochar content (more than 10% biochar/feedstock ratio) favored faster humification, higher available P and S content. [ABSTRACT FROM AUTHOR]

The textile industry generates large volumes of waste throughout its production process. Most of this waste is colored, therefore, discoloration is an important step toward recycling and reusing this waste. This study focused on the chemical reductive discoloration of textile waste composed of cotton dyed with reactive dye. The experimental design demonstrated the significant influence of the concentration of reducing agent and time of reaction on the degree of whiteness of the cotton fibers. The concentration of the alkaline agent was not significant in the process. The optimization of the reaction conditions lead to Berger degree of 50.5 ± 3.5. The discolored cotton was chemically recycled through dissolution in ionic liquid 1-ethyl-3-methylimidazolium chloride and regeneration in film form in water. The microstructure of the regenerated cellulose films was evaluated by Scanning Electron Microscopy (SEM) indicating complete dissolution and uniform regeneration. The discoloration process reduced the polymerization degree and crystallinity index of the cotton fibers but retained the cellulose I structure. The dissolution and cellulose regeneration process results in transparent films with an amorphous structure. The thermal behavior, evaluated by thermogravimetric analysis, indicated that residues and regenerated film presented a main decomposition step. The maximum decomposition rate temperature of the regenerated films was approximately 40°C lower than the cotton fibers, which correlates well with the reduction in polymerization degree and amorphous structure. In general, the study demonstrated that textile cotton waste dyed with reactive dyes can be chemically discolored to form transparent and amorphous films, contributing to the development of sustainable strategies for the textile industry. [ABSTRACT FROM AUTHOR]

Non-traditional lignocellulosic materials are a significant resource for producing high-value products, including nanocellulose. This work studied the nanocellulose obtention from chemical pulps of the two fast-growing bamboo species, Guadua trinii, and Guadua angustifolia. Chemical pulps were produced by soda-anthraquinone (S) pulping from both autohydrolysis-pretreated (H) and unpretreated bamboo chips. Autohydrolysis-pretreated (SHP) and unpretreated soda-anthraquinone (AQ) (SP) pulps were characterized by yield, Kappa number, alpha, beta, and gamma cellulose, degree of polymerization, water retention value, and crystallinity. The nanocellulose was produced by a sequential chemical oxidation treatment (2,2,6,6-tetramethylpiperidine-1-oxyl, TEMPO reagent) and mechanical nanofibrillation. Nanocellulose was characterized by carboxylic group content and viscosity. The results revealed that autohydrolysis pretreatment resulted in a higher hemicelluloses extraction in G. angustifolia. In contrast, the pulping yield of unpretreated samples was higher for G. trinii, and the soda-AQ pulps from this species exhibited better delignification than the autohydrolysis-pretreated pulps. The crystallinity index values of the obtained pulps were high (>80%), and the alpha-cellulose contents were similar. The viscosities of the aqueous nanocellulose suspensions were higher for the nanocellulose solutions obtained from the unpretreated soda-AQ pulps. Besides, nanocellulose from G. trinii unpretreated soda-AQ pulps had a higher rate of carboxylic groups. The results of this work are significant in assessing the potential of both bamboo species as a source of high-value products within the biorefinery framework because the viscosities of the aqueous nanocellulose suspensions depend on the size and shape of nanofibrils. It has significant importance for industrial unit operations and potential applications. [ABSTRACT FROM AUTHOR]

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

Given the pressing threat of global warming, it is imperative to promote CO2 emission reduction within the cement industry which is widely recognized as a major contributor to the overall carbon footprint. Limestone clay cement (LCC) emerges as a promising alternative to Portland cement. However, to facilitate the implementation of LCC technology, it is urgent to address the low early-age compressive strength issue. Inspired by the successful implementation of nano-engineered cementitious material, we hereby introduce a novel nanomaterial, graphene oxide (GO), into unconventional LCC paste (cement:clay:limestone = 65%:20%:15%, water/binder ratio: 0.45). Experimental results revealed that the 0.09% GO by weight of the LCC binder was the optimal dosage in this work, which improved the compressive strength of the LCC paste at 7, 14, and 28 days by 25.6, 21.6, and 20.3%, respectively. Advanced characterizations were then conducted, suggesting that the admixed GO not only enabled a higher polymerization degree of binder hydrates (which benefited the development of compressive strengths) but also improved the carbonation resistance of LCC paste. These findings not only offer valuable insights for researchers but also provide practical guidance for engineers in the field. Notably, the admixed GO converted the unstable orthorhombic crystal systemic aragonite to the stable trigonal crystal systemic calcite, which offers insights into the technology of carbon sequestration in concrete.

This paper presents a theoretical investigation of the design of a new actuator type made of anisotropic colloidal particles grafted with stimuli-responsive polymer chains. These artificial muscles combine the osmotic actuation principle of stimuli-responsive hydrogels with the structural alignment of colloidal liquid crystals to achieve directional motion. The solubility of the stimuli-responsive polymer in the neutral state, its degree of polymerization, the salt concentration, and the grafting density of the polymer chains on the surface of the colloidal particles are investigated and identified as important for actuator performance and tunability. The computational results suggest that the proposed mechanically active material matches or exceeds the performances of natural muscles and provide the guidelines for the realization of artificial muscles with predetermined actuation properties. [ABSTRACT FROM AUTHOR]

Digital light processing (DLP) printing forms solid constructs from fluidic resins by photochemically crosslinking polymeric resins with reactive functional groups. DLP is used widely due to its efficient, high‐resolution printing, but its use and translational potential has been limited in some applications as state‐of‐the‐art resins experience unpredictable and anisotropic part shrinkage due to the use of solvent needed to reduce resin viscosity and layer dependent crosslinking. Herein, poly(allyl glycidyl ether succinate) (PAGES), a low viscosity, degradable polyester, was synthesized by ring opening copolymerization and used in combination with degradable thiol crosslinkers to afford a solvent free resin that can be utilized in DLP printing. Varying resin formulations of PAGES polymer are shown to decrease part shrinkage from 14 % to 0.3 %. Photochemically printed parts fabricated from PAGES possess tensile moduli between 0.43 and 6.18 MPa and degradation profiles are shown to vary between 12 and 40 days under accelerated conditions based on degree of polymerization and crosslink ratio. [ABSTRACT FROM AUTHOR]

Methane fermentation, which is one of the key processes in biogas production, plays an important role in the conversion of biomass to energy. During this process, changes occur in the chemical composition of organic feedstocks, including the chemical composition of grasses. The assessment of these changes is crucial for the efficiency and productivity of biogas production. The material for this study comprised fully mature grass blades with leaves and inflorescences and was collected from extensively used meadows and pastures, as well as cultivated and set-aside areas in the Wielkopolskie Voivodeship, the communes of Białośliwie and Trzcianka, Poland. The aim of this study was to compare methane fermentation efficiency in nine grass species and identify the biomass component involved in biogas production. The results indicate that the fermentation process, as expected, changed the cellulose content. The lignin content of the grasses before fermentation varied more than the cellulose content. The content of holocellulose (sum of carbohydrate components) in the grasses ranged from 59.77 to 72.93% before fermentation. Methane fermentation significantly reduced the carbohydrate content in the grasses, with a low degree of polymerization. Grassland biomass-based biogas production is a viable alternative to conventional fossil fuels. [ABSTRACT FROM AUTHOR]

To achieve efficient degradation of crustacean raw materials and eco-preparation of N-acetyl-oligosaccharides, YS-54 strain screened from offshore soil in Qingdao was used for chitinase preparation in the present study. Chitinase was prepared through 60% ammonium sulfate precipitation and Sephadex G-100 gel filtration chromatography. Enzymatic properties such as optimal temperature, optimal pH, and substrate specificity were characterized. Mass spectrometry was used to determine the polymerization degree of enzymatic products. The 16S rRNA identification result showed that YS-54 strain belonged to the Aeromonas species. Chitinase from Aeromonas sp. YS-54 showed a specific activity of 23.44 U/mg. The molecular weights of chitinase were 63 and 75 kDa as shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Chitinase was stable under the condition of 40 °C and pH5.0. The enzymatic activity was significantly activated by Ba2+, Co2+, Mg2+ and TritonX-100 (P<0.05), while inhibited by Fe3+, Cu2+ and SDS. The specific activity of chitinase toward α-chitin was 7.99 U/mg, 34.09% of that toward colloidal chitin. The polymerization degree of enzymatic hydrolysis products from colloidal chitin and α-chitin were 1~4 and 1~3, respectively. Chitinase from Aeromonas sp. YS-54 was stable in broad range of temperature and pH, meanwhile showed high catalytic efficiency toward α-chitin. The hydrolysis characteristics of chitinase from Aeromonas sp. YS-54 would provide technical support for the comprehensive utilization of crustacean waste. [ABSTRACT FROM AUTHOR]

Functionally graded materials (FGMs) have spatial variations in structure or composition that result in gradients in their mechanical, thermal, swelling, or other properties. FGMs have garnered significant research interest because of their extensive applications in areas such as biomedical implants, sensors, and soft robotics. Recently, grayscale photopolymerization 3D printing has emerged as a promising technology for crafting complex and high‐resolution FGMs. This comprehensive work delves into various grayscale photopolymerization 3D printing techniques, offering insights into their ability to precisely control printing exposure energy and polymerization degree, which in turn influence material properties. Furthermore, this work highlights diverse applications of grayscale vat‐photopolymerization 3D printing. Finally, it offers perspectives on ways to enhance grayscale photopolymerization 3D printing, with a focus on improving printing feedstocks and grayscale strategies. [ABSTRACT FROM AUTHOR]

Reversible addition–fragmentation chain transfer (RAFT) emulsion polymerization of methyl methacrylate (MMA) is successfully performed in water in the presence of a poly(methacrylic acid) (PMAA) macromolecular chain transfer agent (macroCTA) leading to the formation of self‐stabilized PMAA‐b‐PMMA amphiphilic block copolymer particles. At pH 3.7, the reactions are well‐controlled with narrow molar mass distributions. Increasing the initial pH, particularly above 5.6, results in a partial loss of reactivity of the PMAA macroCTA. The effect of the degree of polymerization (DPn) of the PMMA block, the solids content, the nature of the hydrophobic segment, and the pH on the morphology of the obtained diblock copolymer particles is then investigated. Worm‐like micelles are formed for a DPn of PMMA of 20 (PMMA20), while "onion‐like" particles and spherical vesicles are obtained for PMMA30 and PMMA50, respectively. In contrast, spherical particles are obtained for the DPns higher than 150. This unusual evolution of particle morphologies upon increasing the DPn of the PMMA block seems to be related to hydrogen bonds between hydrophilic MAA and hydrophobic MMA units. [ABSTRACT FROM AUTHOR]

To improve the mechanical properties of polydicyclopentadiene (PDCPD), NPs are often used as the inorganic nanofillers to construct PDCPD-based nanocomposites. Whether the NPs can be uniformly dispersed in polymer matrix is the key to prepare high-performance PDCPD. In this work, the oil-soluble Cu NPs was selected as the nanofiller for PDCPD, and the copper/poly- dicyclopentadiene (Cu/PDCPD) nanocomposites was prepared by in-situ polymerization using reaction injection molding (RIM) technology. The relationship between the co-catalyst amount and the gel time at different Cu NPs addition amounts was discussed in detail by RIM technology. The polymerization degree of the polymer was measured by Soxhlet extraction. The morphology, microstructure, and mechanical properties of the as-prepared Cu/PDCPD nanocomposites were characterized by SEM and universal testing machine, respectively. The improved mechanical properties of Cu/PDCPD nanocomposites were mainly attributed to the well interfacial compatibility between the modification layer of Cu NPs and the PDCPD matrix. [ABSTRACT FROM AUTHOR]

In this study, a thermal-responsive triblock polypeptoid, poly(N-octylglycine)-b-poly(N-allylglycine)-b-poly(N-methylglycine) (PNOG-b-PNAG-b-PNMG), was synthesized via continuous polymerization of octyl-N-carboxyanhydride (Oc-NCA), allyl-N-carboxyanhydride (Al-NCA), and methyl-N-carboxyanhydride (Me-NCA) by using benzylamine as the initiator. Remarkably, triblocks were self-assembled into micelles in an aqueous solution. The poly(N-octyl glycine) PNOG blocks form the core of the micelle, while poly(N-methyl glycine) PNMG blocks form a hydrophilic shell. The PNAG block, located between the PNOG and PNMG blocks, is soluble in water and forms part of the hydrophilic shell at low temperatures but becomes hydrophobic and associates with the micelle core at high temperatures. The micelle size transition temperature can be adjusted by changing the polypeptoid structures within the range of 35–38°C. We also systematically investigated the degree of polymerization of polymers and the effect of concentration on assembly. The antibacterial (ciprofloxacin (Cip) drug, is encapsulated in micelles through hydrophobic interactions and released in stages by adjusting the size of the hydrophobic core through temperature changes. [ABSTRACT FROM AUTHOR]

Anthelmintic resistance in gastrointestinal nematodes produces substantial challenges to agriculture, and new strategies for nematode control in livestock animals are called for. Natural compounds, including tannins, with proven anthelmintic activity could be a functional option as structurally diverse complementary compounds to be used alongside commercial anthelmintics. However, the dual use of two anthelmintic components requires an understanding of the pharmacological effects of the combination, while information concerning the interactions between plant-based polyphenols and commercial anthelmintics is scarce. We studied the direct interactions of proanthocyanidins (PAs, syn. condensed tannins) and a commercial anthelmintic thiabendazole, as a model substance of benzimidazoles, by isothermal titration calorimetry (ITC). Our results show evidence of a direct interaction of an exothermic nature with observed enthalpy changes ranging from 0 to −30 kJ/mol. The strength of the interaction between PAs and thiabendazole is mediated by structural characteristics of the PAs with the strongest positive correlation originating from the presence of galloyl groups and the increased degree of polymerization. [ABSTRACT FROM AUTHOR]

The relationship between slag structure and viscosity is studied, employing Raman spectroscopy for the five-component slag system of MnO-SiO2-CaO-Al2O3-MgO and its subsystems. This study aims to investigate the influence of variations in slag composition on viscosity, which is crucial for optimizing industrial processes. Based on industrial slag compositions produced in a silicomanganese submerged arc furnace, 17 slags with a fixed content of MnO of 10 wt% are synthesized with varying contents of SiO2 of 33 to 65 wt%; CaO within the range of 14 to 40 wt%; and fixed contents of Al2O3 and MgO of 17 and 6 wt%, respectively. The slag compositions are divided into four groups, ranging from low basicity (0.38) to high basicity (0.80), with each group containing the four slag systems of MnO-SiO2-CaO, MnO-SiO2-CaO-Al2O3, MnO-SiO2-CaO-MgO, and MnO-SiO2-CaO-Al2O3-MgO, with fixed basicity. Additionally, a five-component composition with the lowest basicity of 0.28 is considered. Raman spectroscopy measurements are performed in the wavenumber range of 200 to 1200 cm − 1 using a green source laser with a 532 nm wavelength. The high-wavenumber region of the Raman spectra (800 to 1200 cm − 1 ) is deconvoluted to quantitatively investigate the effect of each oxide on the slag structure and the degree of polymerization (DOP) of the silicate network. Results indicate that measured NBO/T increases with increasing basicity, demonstrating a reduction in DOP of the silicate structure. This depolymerization effect is more pronounced in slags containing Al2O3 compared to those without it. In a group of slags with similar basicity, the substitution of SiO2 with Al2O3 leads to further depolymerization. In contrast, substituting CaO with MgO has little effect on the silicate structure in slags without Al2O3 but causes depolymerization in slags containing Al2O3. To study the relationship between structure and viscosity, viscosity data obtained from FactSage are used as reference values. The predictions of slag viscosity using the Raman-structure model and the NBO/T viscosity model are then compared to the FactSage results. The adjustable parameters of the Raman-structure model are re-determined using the FactSage data for the studied slag compositions. The NBO/T viscosity model employs both calculated NBO/T values from the slag compositions and measured NBO/T values from the deconvolution results. The findings of this study reveal good agreement between the predictions of the Raman-structure model and the FactSage viscosity data. [ABSTRACT FROM AUTHOR]

An experiment designed to predict the lifetime of the Xuan paper using the viscosity method is introduced in the form of group collaboration. This experiment is targeted at junior students who majored in conservation of cultural relics, with eight groups involved. Using a jacketed viscometer, the intrinsic viscosity of the two types of undegraded and degraded Xuan papers was determined, and the corresponding degree of polymerization (DP) was calculated. Then data were collected from all groups, and degradation rates of the papers were then calculated, which were then used to predict the life expectancy of the Xuan papers. The aim was to enhance students’ teamwork skills, practical experience, problem-solving abilities, data analysis, and scientific research capabilities, while also guiding them to apply their chemical knowledge to practical conservation for paper-based objects. [ABSTRACT FROM AUTHOR]

For the efficient utilization of CO2 into valuable product, the attractive carbon nitride catalysts have been widely studied. In this work, heptazine‐related materials with varying degree of polymerization were designed by an intrinsically modification strategy and employed in the cycloaddition of CO2 with the bisepoxide 1, 4‐butanediol diglycidyl ether (BDODGE). We initially figured out that the sample prepared at 450 °C contained more melem hydrate, exhibiting the best performance. The epoxides conversion and corresponding cyclic carbonates selectivity could achieve 93.1 % and 99.3 % at 140 °C for 20 h without any cocatalyst and solvent, respectively. Results of the catalytic tests suggested that the high catalytic activity was dependent on big size porous structure and the synergetic effect of active amino groups and −OH groups. The role of water in maintaining the specific structure and providing active site has been proved. Moreover, the CN‐450‐W catalyst exhibited outstanding recycling stability. And finally, a plausible reaction mechanism was proposed. [ABSTRACT FROM AUTHOR]

Investigate the bioactivity and stability of Rhodiola rosea (RR) fractions as a natural source of p ro d elphinidin gallate (PDg) on dentin collagen via analysis of the viscoelastic and resin-dentin adhesive properties of the dentin matrix. The biomimicry and stability of RR subfractions (F1, F2, F3 and F4) with collagen were determined by dynamic mechanical analysis (DMA). DMA used a strain sweep method to assess the dentin matrix viscoelastic properties [storage (E'), loss (E"), and complex (E*) moduli and tan δ] after treatment, 7-, 30- and 90-days of storage in simulated body fluids (SBF). Resin-dentin interface properties were assessed after 1 and 90-days in SBF by microtensile bond strength test and confocal laser scanning microscopy. Data were analyzed using two and one-way ANOVA and post-hoc tests (α = 0.05). RR fractions increased dentin matrix complex (96 - 69 MPa) and storage (95 - 68 MPa) moduli, compared to the control (∼9 MPa) in the ranking order: F2 ≥ F3 = F1 = F4 > control (p < 0.001). Treatment did not affect tan δ values. After 30- and 90-days, RR-treated dentin E*, E' and tan δ decreased (p < 0.001). F2 fraction yielded the highest microtensile bond strength (43.9 MPa), compared to F1, F4 (35.9 - 31.7 MPa), and control (29 MPa). RR-treated interfaces mediated stable surface modifications and enhanced collagen-methacrylate resin interactions at the bioadhesive interface. Prodelphinidin gallates from RR are potent and reasonably stable biomimetic agents to dentin. Higher potency of F2 fraction with the dentin matrix and the adhesive interface is associated with a degree of polymerization of 2–3 and gallo(yl) motifs. [Display omitted] • Prodelphinidins (PDg) are an attractive alternative as biomimetic agents to dentin. • Dimeric and trimeric PDg mediated the highest biomimetic activity. • PDg induce stable surface modification and interface to methacrylate resin. • Galloyl motifs of PDg enhance potency to dentin matrix and resin-dentin interface. [ABSTRACT FROM AUTHOR]

Glass lubricant with a suitable viscosity is essential for producing high‐quality titanium products by the hot extrusion process. In this study, a novel lubricant of B2O3–SiO2–Al2O3–Na2O–TiO2 (BSANT) glass was proposed, where the effects of B2O3/SiO2 molar ratio (B/Si) and B2O3 content on viscosity and structure were investigated. The results showed that the BSANT glass viscosity was gradually decreased, and the viscous activation energy was decreased by 20.24% with an increased B/Si ratio from 0.415 to 0.719. This was attributed to the decreased amounts of Q3, [BO4], [AlO4], and bridging oxygen (BO) in the network structure, which in turn resulted in a decreased network degree of polymerization. When B2O3 content was increased from 18.70 to 33.12 mol.%, the melt viscosity value at 950 ℃ was decreased by 64.51%, and the viscous activation energy was reduced by 15.82%. Boron anomalies were also observed in glass melts with the B2O3 content from 28.28 to 33.12 mol.%. The mechanisms responsible for this phenomenon were thoroughly discussed in the study. Additionally, a comparison and discussion of the applications of glass lubricants in metal hot working were presented. A glass lubricant with a specific composition was recommended for use in hot extrusion process within the temperature range of 950–1100°C due to its relatively stable viscosity properties. A novel lubricant of B2O3–SiO2–Al2O3–Na2O–TiO2 (BSANT) glass was proposed, where the effects of B2O3/SiO2 molar ratio (B/Si) and B2O3 content on viscosity and structure were investigated. A glass lubricant with a specific composition was recommended for use in hot extrusion process within the temperature range of 950–1100°C due to its relatively stable viscosity properties. [ABSTRACT FROM AUTHOR]

【Objective】This study aims to investigate the adsorption-desorption characteristics of phosphorus (P) in soils applied with ammonium polyphosphates (APPs) of different polymerization distribution, and to compare these characteristics with those of soils applied with traditional orthophosphates (monoammonium phosphate, MAP; diammonium phosphate, DAP）. It can provide a theoretical basis for the efficient use of APP.【Method】Three kinds of APP (18-58-APP, 16-60-APP and 11-37-APP, whose N-P2O5-K2O were 18-58-0, 16-60-0 and 11-37-0, and the distribution of polymerization degree were 1-2, 1-4 and 1-7, respectively), MAP and DAP were used as test fertilizers. The fertilizers were applied to calcareous and acid purple soils and then were incubated for 56 days. The adsorption-desorption characteristics of P and the physicochemical properties of the soils were determined.【Result】Both Langmuir and Freundlich equations fit the adsorption characteristics of P in the two purple soils well (R² = 0.825-0.997). In the calcareous purple soil, compared with MAP and DAP applied soils, the APP-treated soil showed a 15.1%～20.7% decrease in P adsorption rate and a 4.5%-164.9% increase in desorption rate. The Langmuir KL, adsorption free energy (|ΔG|）, and Freundlich KF values of the APP-treated soil decreased by 20.4%-54.0%, 3.3%-10.6%, and 23.8%-43.8%, respectively, indicating a reduction in the binding force of soil for P. The 11-37-APP treated soil showed the largest changes in these values (KL, |ΔG| and KF values were reduced by 40.8%-54.0%, 7.2%-10.6% and 43.6%-43.8%, respectively). In acid purple soil, the impact of different P fertilizers on the adsorption-desoprtion characteristics of P was not significant, but APP-treated soil tended to reduce P adsorption and promote P desorption. Correlation analysis showed that pH, iron and aluminum oxides, and Olsen-P were significantly correlated with P adsorption parameters in calcareous purple soil and soil Olsen-P was significantly correlated with P adsorption parameters in acid purple soil. APP application in calcareous purple soil decreased complexed iron and aluminum oxides while increased free iron and aluminum oxides, resulting in decreased P adsorption and increased desorption. Compared to calcareous soil, acid purple soil had a lower available P content and a stronger adsorption capacity, making the adsorption-desorption characteristics less susceptible to the influence of different P fertilizers in the short term.【Conclusion】The adsorption-desorption characteristics of P in APP-treated purple soils were influenced by the soil properties and the APP’s polymerization distribution. The significant changes were observed in calcareous purple soil, especially for 11-37-APP with a broader polymerization distribution. [ABSTRACT FROM AUTHOR]

The electrical conductivity of the SiO2–MnO–TiO2 welding fluxes with various MnO/TiO2 mass ratios was measured by the four-electrode alternating current (AC) impedance method. Molecular dynamics (MD) simulations were employed to detect the effect of MnO/TiO2 mass ratio on the structure of SiO2–MnO–TiO2 welding fluxes. The experimental results showed that within the temperature range of 1673 K to 1793 K, the electrical conductivity of the welding fluxes increased while their apparent activation energy reduced with the increased MnO/TiO2 mass ratio from 1.03 to 3.63. Molecular dynamics simulations indicated that the coordination numbers of Si–Si, Si–Ti and Ti–Ti, and the proportion of complex structural units (bridging oxygen, Q3(Si) and Q4(Si)) reduced with the increased MnO/TiO2 mass ratio. Additionally, it could be concluded that the electrical conductivity of the SiO2–MnO–TiO2 welding fluxes positively correlated with the decrease in the degree of polymerization of the fluxes caused by the increased MnO/TiO2 mass ratio. [ABSTRACT FROM AUTHOR]

The crystallization behavior, viscosity and structure of CaO–SiO2–MgO–Al2O3 melts with different Al2O3 contents and CaO/SiO2 mass ratios were investigated. The local structures of oxide glasses were determined by Raman spectroscopy to correlate their crystallization behaviors. The crystallization temperature of the oxide melts increases as the Al2O3 content is increased from 15 to 30 mass pct, indicating an increased crystallization tendency. However, the crystallization ability of the oxide melts was lowered with the increase in the Al2O3 content. Since the polymerization degree of the aluminosilicate network increases, the viscosity of the oxide melts increases as the Al2O3 content is increased from 15 to 30 mass pct, resulting in suppressed crystallization ability. The reduction of the viscosity of oxide melts with increasing CaO/SiO2 mass ratio from 0.8 to 1.2 is dominated by a reduced polymerization degree of the oxide melts, resulting in the crystallization enhancement of oxide melts. [ABSTRACT FROM AUTHOR]

Ca3(PO4)2 is selected to be added to the basalt to simulate basalt mixed sludge in order to produce glass and continuous fiber. XRD and Raman are used to analyze basalt glass with varied Ca3(PO4)2 additions. Basalt glass is amorphous, according to XRD measurements. However, Ca3(PO4)2 alters the Raman spectra of basalt glass noticeably. Raman results show Ca3(PO4)2 increases the degree of polymerization of the glass, but the degree of polymerization decreases with the further increase of Ca3(PO4)2 content. The dielectric characteristics are tested at a frequency of 1 MHz. When the addition amount of Ca3(PO4)2 is 1 g, it has the lowest dielectric constant of 6.567. When the addition amount is 2 g, it has the lowest dielectric loss of 0.0026. The volume resistivity of the sample without Ca3(PO4)2 is 4.227 × 1013 Ω· cm (25 °C). With the increase of Ca3(PO4)2 content, the volume resistivity decreases, reaching the lowest 1.78 × 1013 Ω·cm when the addition amount is 2 g (25 °C). With the increase of Ca3(PO4)2 content, the fiber diameter becomes larger, the crack decreases and the fracture frequency decrease. So the sludge can be considered as an addition in the continuous fiber production. [ABSTRACT FROM AUTHOR]

Many α-agarases have been characterized and are utilized for producing agarooligosaccharides through the degradation of agar and agarose, which are considered valuable for applications in the food and medicine industries. However, the catalytic mechanism and product transformation process of α-agarase remain unclear, limiting further enzyme engineering for industrial applications. In this study, an α-agarase from Catenovulum maritimus STB14 (Cm-AGA) was employed to degrade agarose oligosaccharides (AGOs) with varying degrees of polymerization (DPs) to investigate the catalytic mechanism of α-agarases. The results demonstrated that Cm-AGA could degrade agarose into agarotetraose and agarohexaose. The reducing ends of agarotetraose and agarohexaose spontaneously release unstable 3,6-anhydro-α-l-galactose molecules, which were further degraded into agarotriose and agaropentose. Cm-AGA cannot act on α-1,3-glucoside bonds in agarotriose, agarotetraose, neoagarobiose, and neoagarotetraose but can act on AGOs with a DP greater than four. The product analysis was further verified by β-galactosidase hydrolysis, which specifically cleaves the non-reducing glycosidic bond of agarooligosaccharides. Multiple sequence alignment results showed that two conserved residues, Asp994 and Glu1129, were proposed as catalytic residues and were further identified by site-directed mutagenesis. Molecular docking of Cm-AGA with agaroheptose revealed the potential substrate binding mode of the α-agarase. These findings enhance the understanding of Cm-AGA's catalytic mode and could guide enzyme engineering for modulating the production of agarooligosaccharides. [ABSTRACT FROM AUTHOR]

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

Nanocellulose is not only a renewable material but also brings functions that are opening new technological opportunities. Here we discuss a special subset of this material, in its fibrillated form, which is produced by aerobic microorganisms, namely, bacterial nanocellulose (BNC). BNC offers distinct advantages over plant-derived counterparts, including high purity and high degree of polymerization as well as crystallinity, strength, and water-holding capacity, among others. More remarkably, beyond classical fermentative protocols, it is possible to grow BNC on non-planar interfaces, opening new possibilities in the assembly of advanced bottom-up structures. In this review, we discuss the recent advances in the area of BNC-based biofabrication of three-dimensional (3D) designs by following solid- and soft-material templating. These methods are shown as suitable platforms to achieve bioadaptive constructs comprising highly interlocked biofilms that can be tailored with precise control over nanoscale morphological features. BNC-based biofabrication opens applications that are not possible by using traditional manufacturing routes, including direct ink writing of hydrogels. This review emphasizes the critical contributions of microbiology, colloid and surface science, as well as additive manufacturing in achieving bioadaptive designs from living matter. The future impact of BNC biofabrication is expected to take advantage of material and energy integration, residue utilization, circularity and social latitudes. Leveraging existing infrastructure, the scaleup of biofabrication routes will contribute to a new generation of advanced materials rooted in exciting synergies that combine biology, chemistry, engineering and material sciences. [ABSTRACT FROM AUTHOR]