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We present the explicit bonding Reaction ensemble Monte Carlo (eb-RxMC) method, designed to sample reversible bonding reactions in macromolecular systems in thermodynamic equilibrium. Our eb-RxMC method is based on the reaction ensemble method; however, its implementation differs from the latter by the representation of the reaction. In the eb-RxMC implementation, we are adding or deleting bonds between existing particles, instead of inserting or deleting particles with different chemical identities. This new implementation makes the eb-RxMC method suitable for simulating the formation of reversible linkages between macromolecules, which would not be feasible with the original implementation. To enable coupling of our eb-RxMC algorithm with molecular dynamics algorithm for the sampling of the configuration space, we biased the sampling of reactions only within a certain inclusion radius. We validated our algorithm using a set of ideally behaving systems undergoing dimerization and polycondensation reactions, for which analytical results are available. For dimerization reactions with various equilibrium constants and initial compositions, the degree of conversion measured in our simulations perfectly matched the reference values given by the analytical equations. We also showed that this agreement is not affected by the arbitrary choice of the inclusion radius or the stiffness of the harmonic bond potential. Next, we showed that our simulations can correctly match the analytical results for the distribution of the degree of polymerization and end-to-end distance of ideal chains in polycondensation reactions. Altogether, we demonstrated that our eb-RxMC simulations correctly sample both reaction and configuration spaces of these reference systems, opening the door to future simulations of more complex interacting macromolecular systems. [ABSTRACT FROM AUTHOR]

Mixing Gibbs energy and phase equilibria of aqueous solutions of polyglycine were studied theoretically by means of polymer reference interaction site model integral equation theory combined with the Gibbs–Duhem method. In addition to the ordinary liquid–liquid phase separation between dilute and concentrated solutions, the theoretical calculation predicted the coexistence of two coacervate phases, namely, the lower- and higher-density coacervates. The relative thermodynamic stabilities of these two phases change with the polymerization degree of polyglycine. The higher-density coacervate phase was rapidly stabilized by increasing the polymer length, and the lower-density phase became metastable at large polymers. The hydrogen bonds between the peptide chains were strengthened, and water was thermodynamically destabilized in the higher-density coacervate. A possible relation with the formation of amyloid fibril within a liquid droplet is also discussed. [ABSTRACT FROM AUTHOR]

Block copolymers at homopolymer interfaces are poised to play a critical role in the compatibilization of mixed plastic waste, an area of growing importance as the rate of plastic accumulation rapidly increases. Using molecular dynamics simulations of Kremer–Grest polymer chains, we have investigated how the number of blocks and block degree of polymerization in a linear multiblock copolymer impacts the interface thermodynamics of strongly segregated homopolymer blends, which is key to effective compatibilization. The second virial coefficient reveals that interface thermodynamics are more sensitive to block degree of polymerization than to the number of blocks. Moreover, we identify a strong correlation between surface pressure (reduction of interfacial tension) and the spatial uniformity of block junctions on the interface, yielding a morphological framework for interpreting the role of compatibilizer architecture (number of blocks) and block degree of polymerization. These results imply that, especially at high interfacial loading, the choice of architecture of a linear multiblock copolymer compatibilizing surfactant does not greatly affect the modification of interfacial tension. [ABSTRACT FROM AUTHOR]

Oligosaccharides, a low polymerization degree of carbohydrate, possess various physiological activities, such as anti-diabetes, anti-obesity, anti-aging, anti-viral, and gut microbiota regulation, having a widely used in food and medical fields. However, due to the limited natural oligosaccharides, many un-natural oligosaccharides from complex polysaccharides are being studied for amplifying the available pool of oligosaccharides. More recently, various oligosaccharides were developed by using several artificial strategies, such as chemical degradation, enzyme catalysis, and biosynthesis, then they can be applied in various sectors. Moreover, it has gradually become a trend to use biosynthesis to realize the synthesis of oligosaccharides with clear structure. Emerging research has found that un-natural oligosaccharides exert more comprehensive effects against various human diseases through multiple mechanisms. However, these oligosaccharides from various routes have not been critical reviewed and summarized. Therefore, the purpose of this review is to present the various routes of oligosaccharides preparations and healthy effects, with a focus on diabetes, obesity, aging, virus, and gut microbiota. Additionally, the application of multi-omics for these natural and un-natural oligosaccharides has also been discussed. Especially, the multi-omics are needed to apply in various disease models to find out various biomarkers to respond to the dynamic change process of oligosaccharides. [ABSTRACT FROM AUTHOR]

Oil–pressboard insulation in converter transformer is subjected to the combined effects of AC and DC electric fields, high temperature, and mechanical vibration in actual operation, with a serious impact on its deterioration. In this study, comparative tests are performed of coupled electrical–thermal–mechanical aging, and several characteristic parameters that characterize the degree of aging of oil–pressboard are measured. Relationships between aging parameters are established, with the degree of polymerization (DP) of the pressboard being adopted as the criterion to characterize the degree of aging. Scanning electron microscopy and X-ray diffraction are used to investigate the surface morphology and crystal structure of the pressboard at different aging stages. Then, the influences of temperature, electric field and mechanical field on the cracking mechanism of the oil–pressboard insulation in terms of the aging characteristic parameters and the changes in cellulose crystallinity were analyzed. It is finally found that thermal stress is the most important factor involved in insulation pressboard cracking. The addition of electric and mechanical fields will reduce the crystallite size of the cellulose pressboard material, increase the acid value and furfural content of the oil, and increase the rate of decrease in the degree of polymerization of the pressboard. All of which accelerate the aging of the oil–pressboard insulation. [ABSTRACT FROM AUTHOR]

Lignocellulosic biomass (LCB) comprising of wheat bran, coconut husk, rice husk, cereals straw, and other hardwood and softwoods is a good source for the production of xylooligosaccharides (XOS) (prebiotic). XOS produced are nondigestible carbohydrates being stable under stomach pH and digestive enzymes so they can be easily delivered to the intestine in native form, thus stimulating the growth of probiotics. Here we review about the raw material, production, purification, and application of XOS with health benefits. Importance of XOS being valuable food ingredient is increasing as they perform a variety of functions, including reduction in cholesterol levels, gastrointestinal health maintenance, anticancer and antioxidant properties, and modulation of immune system. We also discuss the different characterization methods which are necessary to determine the degree of polymerization (DP) of XOS. Low DP (xylobiose and xylotriose) is usually preferred for the application of XOS in various sectors. This review emphasizes the growing significance of XOS as a prebiotic, serving as nourishment for probiotics. [ABSTRACT FROM AUTHOR]

Membranes offer a potentially energy‐efficient and space‐saving solution to reduce CO2 emissions and combat global warming. However, engineering membranes with advanced materials for high permeance and reasonable selectivity is a pressing need. In this context, a series of carbazole‐based conjugated microporous polymer (CMP) membranes are fabricated with thicknesses of a few hundred nanometers through in situ electropolymerization for post‐combustion carbon capture. The findings reveal that various experimental conditions, including the monomer concentration, electric potential, and cyclic voltammetry (CV) cycling number, largely impact the polymerization degree of the carbazole‐based CMP, thus influencing the mode of polymer chain packing. An optimal polymerization degree leads to a larger micropore size and a higher fractional free volume (FFV), thus allowing fast CO2 transport. The study first demonstrates the feasibility of using CMPs to fabricate thin film composite (TFC) membranes for post‐combustion carbon capture and confirms the high controllability of their micropores. These insights provide instructive guidance for the future advancement of CMP applications in membrane fabrication for gas separation and other fields that require precise micropore generation and design. [ABSTRACT FROM AUTHOR]

Theoretical analysis of the kinetic scheme describing formation and randomization of a binary copolymer due to end‐group interchange reactions is presented. Compact analytical expressions are obtained for the transient and equilibrium values of the copolymer degree of blockiness and fractions of active end‐groups of different types. The resulting copolymer is described by the first‐order Markov statistics, which can be rather far from the Bernoullian one. Its structure is determined by the composition of the system and a single combination of the rate constants of four elementary reactions. The kinetics includes fast and slow stages with characteristic time periods independent of and proportional to the average polymerization degree, respectively. During the fast stage, the initial polymers disappear, whereas the copolymer degree of blockiness is still very low. The distribution of units in the copolymer is Markovian, only if the initial polymers possess the most probable molar mass distributions. At the slow stage copolymer randomization gradually progresses, whereas the distribution of end groups may change in the opposite direction compared to the fast stage. The results can be used to analyze the experimental data on the chain structure of condensation, metathesis, and dynamic covalent polymers, where interchange reactions play a significant role. [ABSTRACT FROM AUTHOR]

The thermo-solvent-tolerant lipase-producing actinomycete, Streptomyces sp. A3301, was utilized as a biocatalyst for poly (lactic acid) or PLA polymerization. The study aimed to optimize lipase immobilization conditions, characterize the immobilized lipase and apply it for PLA polymerization. The results showed using a sponge as the immobilizing matrix was the most effective method, achieving a maximum activity of 277 U/g of sponge. The optimal sponge size was determined to be 0.125 cm³ and pre-soaking the sponge in 0.1 M phosphate buffer at pH 7.0 for 24 h before use proved advantageous. Immobilization significantly enhanced the thermo-stability of the enzyme, with a relative activity ranging from 140 to 190% within the temperature range of 30 to 60 °C. In contrast, the crude lipase exhibited thermo-stability only within the 30 - 50 °C range. The immobilized lipase demonstrated stability under PLA polymerization conditions, which involved a reaction mixture containing toluene and lactic acid and performed at 60 °C for 8 h. The immobilized lipase maintained its activity under this condition for 5 h, retaining a relative activity of 230%, which was 1.2 times higher than the activity of the crude lipase. When the immobilized lipase was used in PLA polymerization, the resulting PLA product exhibited a molecular weight of 5,333 ± 0.02 Da, and the degree of polymerization was approximately 72. These findings underscore the potential of the immobilization technique to enhance lipase activity for PLA polymerization. [ABSTRACT FROM AUTHOR]

The surface wetting or coating of materials by polymers is crucial for designing functional interfaces and various industrial applications. However, the underlying mechanisms remain elusive. In this study, the wetting behavior of hydroxyl-terminated polybutadiene (HTPB) on a quartz surface was systematically investigated using computer simulation methods. A notable tip-dominant surface adsorption mode of HTPB was identified, where the hydroxyl group at the end of the polymer chain binds to the surface to initiate the wetting process. Moreover, it was found that with the increase in the degree of polymerization (e.g., from DP = 10 to 30), spontaneous adsorption of HTPB becomes increasingly difficult, with a three-fold increase in the adsorption time. These results suggest a competition mechanism between enthalpy (e.g., adhesion between the polymer and the surface) and entropy (e.g., conformational changes in polymer chains) that underlies the wetting behavior of HTPB. Based on this mechanism, two strategies were employed: altering the degree of polymerization of HTPB and/or regulating the amount of interfacial water molecules (e.g., above or below the threshold amount of 350 on a 10 × 10 nm2 surface). These strategies effectively modulate HTPB's surface wetting process. This study provides valuable insights into the mechanisms underlying the surface adsorption behavior of HTPB and offers guidance for manipulating polymer wetting processes at interfaces. [ABSTRACT FROM AUTHOR]

New asphalt mixtures have been improved by using fibers (polypropylene, polyester, asbestos, carbon, glass, nylon, lignin, coconut, sisal, recycled rubber, PET, wood, bamboo, and cellulose), reducing the temperature and compaction energy for their collocation, minimizing the impact on the environment, increasing the tenacity and resistance to cracking of hot mix asphalt (HMA), preventing asphalt drainage in a Stone Mastic Asphalt (SMA). Hence, this paper aims to evaluate the influence of the chemical (lignin content, ash, viscosity, degree of polymerization, and elemental analysis), morphological (SEM), spectroscopic (FTIR-ATR and XRD), and calorimetric (ATG and DSC) properties of celluloses from bagasse Agave tequilana Weber var. Azul (ABP), corrugated paperboard (CPB) and commercial cellulose fiber (CC) as Schellenberg drainage (D) inhibitors of the SMA. The ABP was obtained through a chemical process by alkaline cooking, while CPB by a mechanical refining process. The chemical, morphological, spectroscopic, and calorimetric properties were similar among the analyzed celluloses, but CPB and ABP cellulose are excellent alternatives to CC cellulose for inhibiting drainage. However, CPB is the most effective at low concentrations. This is attributed to its morphology, which includes roughness, waviness, filament length, orientation, and diameter, as well as its lignin content and crystallinity. [ABSTRACT FROM AUTHOR]

Inulin, a widely recognized prebiotic, has diverse applications across various industrial sectors. Although inulin is primarily produced through plant extraction, there is growing interest in enzymatic synthesis as an alternative. The enzymatic production of inulin from sucrose, which yields polymers with degrees of polymerization similar to those of plant-derived inulin, shows potential as a viable replacement for traditional extraction methods. In this study, an inulosucrase from Neobacillus bataviensis was identified, demonstrating a non-processive mechanism specifically tailored for synthesizing inulin with polymerization degrees ranging from 3 to approximately 40. The enzyme exhibited optimal activity at pH 6.5 and 55 °C, efficiently producing inulin with a yield of 50.6%. Ca2+ can improve the activity and thermostability of this enzyme. To enhance catalytic total activity, site-directed and truncated mutagenesis techniques were applied, resulting in the identification of a mutant, T149S, displaying a significant 57% increase in catalytic total activity. Molecular dynamics simulations unveiled that the heightened flexibility observed in three surface regions positively influenced enzymatic activity. This study not only contributes to the theoretical foundation for inulosucrase engineering but also presents a potential avenue for the production of inulin. [ABSTRACT FROM AUTHOR]

Endo-β-1,3-glucanase is a glycoside hydrolase (GH) that plays an essential role in the mineralization of β-glucan polysaccharides. In this study, the novel gene encoding an extracellular, non-modular GH16 endo-β-1,3-glucanase (GluH) from Hymenobacter siberiensis PAMC 29290 isolated from Arctic marine sediment was discovered through an in silico analysis of its whole genome sequence and subsequently overexpressed in Escherichia coli BL21. The 870-bp GluH gene encoded a protein featuring a single catalytic GH16 domain that shared over 61% sequence identity with uncharacterized endo-β-1,3-glucanases from diverse Hymenobacter species, as recorded in the National Center for Biotechnology Information database. The purified recombinant endo-β-1,3-glucanase (rGluH: 31.0 kDa) demonstrated peak activity on laminarin at pH 5.5 and 40°C, maintaining over 40% of its maximum endo-β-1,3-glucanase activity even at 25°C. rGluH preferentially hydrolyzed D-laminarioligosaccharides and β-1,3-linked polysaccharides, but did not degrade D-laminaribiose or structurally unrelated substrates, confirming its specificity as a true endo-β-1,3-glucanase without ancillary GH activities. The biodegradability of various substrate polymers by the enzyme was evaluated in the following sequence: laminarin > barley β-glucan > carboxymethyl-curdlan > curdlan > pachyman. Notably, the specific activity (253.1 U mg–1) and catalytic efficiency (kcat/Km: 105.72 mg–1 s–1 mL) of rGluH for laminarin closely matched its specific activity (250.2 U mg–1) and kcat/Km value (104.88 mg–1 s–1 mL) toward barley β-glucan. However, the kcat/Km value (9.86 mg–1 s–1 mL) of rGluH for insoluble curdlan was only about 9.3% of the value for laminarin, which correlates well with the observation that rGluH displayed weak binding affinity (< 40%) to the insoluble polymer. The biocatalytic hydrolysis of D-laminarioligosaccharides with a degree of polymerization between 3 and 6 and laminarin generally resulted in the formation of D-laminaribiose as the predominant product and D-glucose as the secondary product, with a ratio of approximately 4:1. These findings suggest that highly active rGluH is an acidic, cold-adapted D-laminaribiose- and D-glucose-releasing GH16 endo-β-1,3-glucanase, which can be exploited as a valuable biocatalyst for facilitating low temperature preservation of foods. [ABSTRACT FROM AUTHOR]

AbstractPoly(δ-valerolactone) (PVL) is a polymer that has garnered significant researcher interest due to its intriguing features and prospective uses across numerous domains, particularly in medicine. This work aimed to assess the influence of the Lewis acidity of the bis(β-diketonate)Zr catalyst complex on the ring-opening polymerization of δ-valerolactone. The ligand in the compound contains an electron-donating group, specifically the methyl group (2a). Furthermore, electron-withdrawing groups employed include phenyl (2b–2c) and trifluoromethyl groups (2d). Characterization data indicate that PVL has been successfully synthesized with a bis(β-diketonate)Zr complex catalyst. The hierarchy of Lewis acid strength for the bis(β-diketonate)Zr complex is 2c > 2b > 2d ≫ 2a. The sequence of PVL DP from highest to lowest is 2b, 2c, 2d and 2a. Nonetheless, the elevated Lewis acidity of complex 2c does not provide PVL with the greatest degree of polymerization. The steric barrier of complex 2c, which contains two phenyl groups, is larger than that in complex 2b. Consequently, the coordination process of the nucleophilic monomer with the electrophilic zirconium central atom becomes increasingly difficult. [ABSTRACT FROM AUTHOR]

Taxodium ‘Zhongshanshan’ is a distinctive tree known for its rapid growth and robust stress resilience. To enhance the utilization of forestry resources, tannin extracts were procured from the barks (BE) and leaves (LE) of Taxodium ‘Zhongshanshan’. The tannin structures were characterized by FT-IR and MALDI-TOF MS, and found to be condensed tannin with a degree of polymerization not exceeding 6. The tannin extracts exhibited a potent ability to scavenge free radicals at capacities of 60–80 % compared to Vitamin C (VC). They inhibited the bacterial strains Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), with a pronounced effect on the latter. Furthermore, tannin from Taxodium ‘Zhongshanshan’ appears benign and have no significant effect on cell activity. [ABSTRACT FROM AUTHOR]

Despite considerable interest in heteroatom‐containing conjugated polymers, there are only few examples with heavier p‐block elements in the conjugation path. The recently reported heavier acyclic diene metathesis (HADMET) allowed for the synthesis of a polymer containing Ge=Ge double bonds—albeit insoluble and with limited degree of polymerization. By incorporation of long alkyl chains, we now obtained soluble representatives, which exhibit degrees of polymerization near infinity according to diffusion‐ordered NMR spectroscopy (DOSY) and dynamic light scattering (DLS). UV/Vis and NMR data confirm the presence of σ,π‐conjugation across the silylene‐phenylene linkers between the Ge=Ge double bonds. Favorable intermolecular dispersion interactions lead to ladder‐like cylindrical assemblies as confirmed by X‐ray diffraction (XRD), small angle X‐ray scattering (SAXS) and DLS. AFM and TEM images of deposited thin films reveal lamellar ordering of extended polymer bundles. [ABSTRACT FROM AUTHOR]

In low‐density polyethylene (LDPE) production, low‐molecular‐weight species are used as chain transfer agents (CTAs). They reduce the degree of polymerization, which has an impact on the polymer properties, such as processability. To specifically adjust the product properties, a detailed understanding of the transfer kinetics to CTAs is indispensable. Thus, the transfer activity of various primary, secondary, and tertiary alcohols as well as diols was investigated experimentally between 120 °C and 250 °C at 2000 bar. The results were evaluated using the Mayo and chain length distribution (CLD) method, and the latter was found to give more reliable results. It was observed that the hydroxy group systematically increases transfer activity compared to alkanes. Additionally, a linear increase of transfer activity with the number of hydrogen atoms is found. [ABSTRACT FROM AUTHOR]

Low‐basicity fluorine‐containing mold flux, which forms a porous slag film with NaF pores, is expected to solve the contradiction between heat transfer and lubrication in the continuous casting of peritectic steel. Herein, the kinetic mechanism and the influence of NaF gas formation based on the different fluorine raw materials (NaF, CaF2, and Na3AlF6) at 0.9 basicity and 6 wt% fluorine are investigated by the combination of experiments and calculations. The results show that CaF2 is the first to generate NaF gas at 1189 K, followed by Na3AlF6 (1238 K) and NaF (1328 K). NaF raw material produces the most NaF gas with the lowest activation energy in the three raw materials, due to high Na ion kinetic energy, the simple degree of polymerization, and Na‐F1 bonds. Correspondingly, NaF bubbles in the molten slag are the largest based on their aggregation. Na3AlF6 and CaF2 raw materials rank second and third, with F atoms primarily bonded as Al‐Fx and Ca‐Fx and the higher proportion of QSi−O−Al2$Q_{\text{Si} - \text{O} - \text{Al}}^{2}$ and QSi−O−Si4$Q_{\text{Si} - \text{O} - \text{Si}}^{4}$ structure. Notably, at 0.9 basicity and 6 wt% fluorine, Na3AlF6 as raw material generates a suitable amount of gas, making diffuse and fine NaF bubbles in the molten slag. [ABSTRACT FROM AUTHOR]

Introduction: Atherosclerosis (AS) is considered the underlying cause of many diseases, particularly cardiovascular and cerebrovascular diseases. Inulin, a type of fructan, has shown potential in improving atherosclerosis, although there are conflicting findings. It is hypothesized that the polymerization degree of inulin may largely influence its therapeutic effectiveness. Therefore, this study aimed to investigate the effects and mechanisms of short-chain and long-chain inulin in AS. Methods: ApoE−/− mice fed a high fat diet (HFD) were used to establish an atherosclerosis model. These mice received daily oral administration of either short-chain or long-chain inulin for 12 weeks. Plasma lipid metabolism-related indices were measured using biochemical analysis, and plasma immunological indices were analyzed via ELISA. The aorta, aortic root regions, liver tissue, adipose tissue, and colon tissue were examined through various staining techniques, including ORO staining, hematoxylin and eosin staining, Alcian blue staining, and immunofluorescent or immunohistochemical assays. Microbiome analysis was conducted in the cecal content. Results: The results indicated that both short-chain and long-chain inulin substantially reduced the formation of atherosclerotic plaques. Inulin also improved plasma lipid concentrations and hepatic lipid metabolism, and partially alleviated both localized (atherosclerotic lesions) and systemic inflammation. Short-chain inulin was more effective than long-chain inulin in reducing atherosclerotic plaques formation, enhancing lipid metabolism and reducing inflammation. Additionally, both types of inulin showed similar effectiveness in enhancing intestinal epithelial barrier integrity, gut microbiota composition and functionality. Conclusion: These findings suggest that inulin has a protective role against atherosclerosis by enhancing lipid metabolism, reducing inflammation, and improving intestinal barrier and gut microbiota. As a dietary intervention, shortchain inulin is more effective than long-chain inulin, offering clinical implications for using inulin as a therapeutic agent for atherosclerosis. [ABSTRACT FROM AUTHOR]

This study compared the physical properties and mechanical strength development of PCBAs with water, sealed, standard, and open ambient air curing over 28 days to find a suitable curing method for the production of phosphogypsum-based cold-bonded aggregates. The types and relative amounts of hydration products, microstructural morphology and pore structure parameters were characterized utilizing XRD, TGA, FTIR, SEM and nitrogen adsorption methods. According to the results, water curing leads to rapid increases in single aggregate strength, reaching 5.26 MPa at 7 d. The standard curing condition improved the 28 d mechanical strength of the aggregates by 19.3% over others by promoting the generation of hydration products and the transformation of the C-S-H gel to a higher degree of polymerization and by optimizing the pore structure. Further, PCBAs achieved an excellent solidification of phosphorus impurities under all four curing conditions. This work provides significant guidance for selecting an optimized PCBA curing method for industrial production. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) have emerged as versatile materials with many applications, such as carbon capture, molecular separation, catalysis, and energy storage. Traditionally, flexible building blocks have been avoided due to their potential to disrupt ordered structures. Recent studies have demonstrated the intriguing properties and enhanced structural diversity achievable with flexible components by judicious selection of building blocks. This study presents a novel series of ionic COFs (ICOFs) consisting of tetraborate nodes and flexible linkers. These ICOFs use borohydrides to irreversibly deprotonate the alcohol monomers to achieve a high degree of polymerization. Structural analysis confirms the dia topologies. Reticulation is explored using various monomers and metal counterions. Also, these frameworks exhibit excellent stability in alcohols and coordinating solvents. The materials have been tested as single‐ion conductive solid‐state electrolytes. ICOF‐203‐Li displays one of the lowest activation energies reported for ion conduction. This tetraborate chemistry is anticipated to facilitate further structural diversity and functionality in crystalline polymers. [ABSTRACT FROM AUTHOR]

The influences of temperature and compositions (TiO 2 and CaO/SiO 2) on thermodynamics properties and structural evolutions of TiO 2 -CaO-Al 2 O 3 -MgO-SiO 2 slags were investigated in this work. The slag viscosities increased with decreasing the temperature and declined with adding TiO 2. With the raising of CaO/SiO 2 ratio, the viscosity decreased under high temperatures, while it increased with the temperature further decreased lower than 1420 °C. The enthalpy change of the slag increased with raising the temperature as well as the TiO 2 content and reduced with the CaO/SiO 2 ratio increasing. Both the liquidus temperature and break point temperature of the slags decreased with adding TiO 2 and increased with raising the CaO/SiO 2 ratio. Temperature had a significant effect on slag structure evolutions, which decreased the slag polymerization degree. With adding TiO 2 and CaO/SiO 2 ratio in slags, the slag structure stability was weakened by increasing the amount of simpler silicate and TiO 6 units and reducing the proportion of complex Ti-O units. Both the temperature and compositions (TiO 2 and CaO/SiO 2) depolymerized the slag structure to decline the viscosity. [ABSTRACT FROM AUTHOR]

The effects of B 2 O 3 on viscosities, structures and phase transitions of CaO–MgO–Al 2 O 3 –SiO 2 –MnO-(0-8.0 wt%)B 2 O 3 slags were investigated in this work. From the viscosity experimental results, the slag viscosities declined and the E η decreased from 205.19 to 175.95 kJ/mol with the addition of B 2 O 3 in slags from 0 to 8.0 wt%. From the structure analysis by using FTIR and XPS, B 2 O 3 entered into the silicate network to increase the slag polymerization degree, while the formation of simple two-dimensional BO 3 trihedral units could significantly decline the symmetry and stability of the structure. The effects of decreasing the network stability and forming low-melting eutectics were more dominated than the effects of increasing the structure polymerization degree, which could reduce the slag viscosity. Furthermore, adding B 2 O 3 could decrease the slag initial precipitation temperature and change the primary crystal phase of the slag from melilite to spinel. The comprehensive effects of reducing the slag structure stability and decreasing the influence of solid phase on viscosity eventually resulted in the improvement of the slag fluidity. [ABSTRACT FROM AUTHOR]

A simple method was developed to produce polymeric nanoribbons and other nanostructures in water. This approach incorporates a perylene diimide (PDI) functionalized by triethylene glycol (TEG) as a hydrophobic supramolecular structure directing unit (SSDU) into the core of hydrophilic poly(N,N‐dimethylacrylamide) (PDMAc) chains using RAFT polymerization. All PDI‐functional polymers dissolved spontaneously in water, forming different nanostructures depending on the degree of polymerization (DPn): nanoribbons and nanocylinders for DPn=14 and 22, and spheres for DPn>50 as determined by cryo‐TEM and SAXS analyses. UV/Vis absorption spectroscopy was used to monitor the evolution of the PDI absorption signal upon dissolution. In solid form, all polymers show a H‐aggregate absorption signature, but upon dissolution in water, the shortest DPn forming nanoribbons evolved to show HJ‐aggregate absorption signals. Over time, the J‐aggregate band increased in intensity, while cryo‐TEM monitoring evidenced an increase in the nanoribbon's width. Heating the nanoribbons above 60 °C, triggered a morphological transition from nanoribbons to nanocylinders, due to the disappearance of J‐aggregates, while H‐aggregates were maintained. The study shows that the TEG‐PDI is a powerful SSDU to promote 2D or 1D self‐assembly of polymers depending on DPn through simple dissolution in water. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Oil‐in‐oil nonaqueous emulsions are of great interest for developing emulsion‐templated polymers and encapsulation systems that are incompatible with water‐sensitive substances. Tailor‐made amphiphilic block copolymers are by far the most efficient stabilizers for oil‐in‐oil emulsions while less attention is given to copolymers with more complex architectures. Here, we report the stabilization of DMSO‐silicone oil interface by bottlebrush random copolymers (BRCPs) containing norbornene backbones with densely grafted poly(methyl methacrylate) (PMMA) and polystyrene (PS) side chains. The assembly kinetics of BRCPs at the DMSO‐silicone oil interface can be divided into three processes, including diffusion, reconfiguration and reorganization, and can be varied by tuning the degree of polymerization of the backbone (NB). Due to the high efficiency of BRCPs in reducing the interfacial tension, when using BRCPs as stabilizers, stable silicone oil‐in‐DMSO traditional emulsions and high internal phase emulsions (HIPEs) can be successfully obtained, while no stable emulsions can be achieved with linear PMMA‐b‐PS serving as the stabilizer. This study, for the first time, underscores the great potential of amphiphilic bottlebrush copolymers in preparing oil‐in‐oil emulsions. Given the advances in polymerization strategy, a broad variety of amphiphilic bottlebrush copolymers are expected to be synthesized and applied in the stabilization of nonaqueous biphasic systems. [ABSTRACT FROM AUTHOR]

This multidisciplinary study details the biosynthesis of novel non-digestible oligosaccharides derived from rare sugars, achieved through transfructosylation of D-tagatose and L-sorbose by levansucrase from Bacillus subtilis CECT 39 (SacB). The characterization of these carbohydrates using NMR and molecular docking was instrumental in elucidating the catalytic mechanism and substrate preference of SacB. Tagatose-based oligosaccharides were higher in abundance than L-sorbose-based oligosaccharides, with the most representative structures being: β-D-Fru-(2→6)-β-D-Fru-(2→1)-D-Tag and β-D-Fru-(2→1)-D-Tag. In vitro studies demonstrated the resistance of tagatose-based oligosaccharides to intestinal digestion and their prebiotic properties, providing insights into their structure-function relationship. β-D-Fru-(2→1)-D-Tag was the most resistant structure to small-intestinal digestion after three hours (99.8% remained unaltered). This disaccharide and the commercial FOS clustered in similar branches, indicating comparable modulatory properties on human fecal microbiota, and exerted a higher bifidogenic effect than unmodified tagatose. The bioconversion of selected rare sugars into β-fructosylated species with a higher degree of polymerization emerges as an efficient strategy to enhance the bioavailability of these carbohydrates and promote their interaction with the gut microbiota. These findings open up new opportunities for tailoring natural rare sugars, like D-tagatose and L-sorbose, to produce novel biosynthesized carbohydrates with functional and structural properties desirable for use as emerging prebiotics and low-calorie sweeteners. [ABSTRACT FROM AUTHOR]

Hemicellulose is a renewable and environmentally friendly biomass polysaccharide. However, because of the low polymerization degree, conventional hemicellulose-based hydrogels often have poor mechanical properties, severely restricting their potential applications. This study involved preparation of a novel high-strength conductive hemicellulosebased composite hydrogel, modulated by a Na2SO4 solution. The hydrogel matrix with a physicochemical double cross-linking structure was created by adding polyvinyl alcohol to the chemically crosslinked networks of gelatin and dialdehyde xylan (DAX) to improve the enhancing effect. After being soaked in a 1 M Na2SO4 solution for 24 h, the composite hydrogel's network structure was thicker, as revealed by scanning electron microscopy. Its tensile breaking strength (3.02 MPa) and elongation (330.95%) were much higher than those prior to the treatment. Energy dispersive spectroscopy and X-ray diffraction confirmed that the composite hydrogel had a considerable amount of Na+ and SO42- uniformly dispersed throughout. Additionally, the ionic conductivity of the composite hydrogel was measured at 5.4 x 10-3 S/m, indicating a potential use in the field of super-capacitors. [ABSTRACT FROM AUTHOR]

The incorporation of sulfate anions in a suitable host matrix has proven to be a challenging task for glass technologists around the world. Therefore, the present work reports on the solubility and retention of sulfate species, as an invaluable macronutrient for plants, in a multicomponent silicate-phosphate glasses from the SiO2–P2O5–K2O–MgO–CaO–XSO3 system. Glasses containing target [SO4]2− concentrations 0–5 mol.% were synthesized via high-temperature melt-quenching technique, the last stage of which constituted fritting the acquired melt in water. It was observed that this synthesis route broadened the glass-forming range of materials from the studied system, the sulfate capacity of which was determined to be ∼ 2 mol.%. At higher [SO4]2− concentrations, additional sulfur was retained in glasses as crystalline inclusions of sulfate salt. An in-depth insight into the materials' structure revealed that sulfate species exist in the vitreous matrix as units not bonded to either the silico-oxygen or phosphor-oxygen subnetworks, and their addition leads to a gradual increase in the polymerization degree of the former, and to the opposite effect as regards the latter. Thermal analysis of the tested glasses supported the structural studies and demonstrated that the addition of sulfur initially reduces materials' glass stability, leading to its increase after SO3 content reaches 1 mol.%. It was also shown that [SO4]2− species affect local environments of Si and Mg atoms indirectly, inducing changes in the medium-range structure beyond their first coordination spheres presumably involving the rearrangement of potassium cations within the vitreous matrix. [ABSTRACT FROM AUTHOR]

Sijunzi decoction (SJZD) has been widely used to treat splenic deficiency syndrome. Previous studies confirmed that polysaccharides and non‐polysaccharides (NPS) are the main active components of SJZD. This study aimed to investigate the composition and activity of oligosaccharides in NPS. In this study, the oligosaccharide component (named SJZD‐OGS), consisting of several different oligosaccharides, was separated and purified from non‐polysaccharides of SJZD (SJZD_NPS). Ultra‐high‐performance liquid chromatography–ion mobility spectrometry–quadrupole time‐of‐flight mass spectrometry (UHPLC–IMS–QTOF/MS), matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF‐MS), and high‐performance anion‐exchange chromatography with pulsed amperometric detection (HPAEC‐PAD) were used to analyze SJZD‐OGS. SJZD‐OGS, with a molecular weight of 2178 Da, was composed of glucose and fructose, and its chemical composition mainly included fructo‐oligosaccharides (FOS) with a degree of polymerization of 3–14 (DP 3–14). The results of oligosaccharide source exploration demonstrated that the chemical composition of SJZD‐OGS was different from that of the oligosaccharides of each herb in SJZD. In addition, SJZD‐OGS showed good anti‐inflammatory activity on macrophage cells and intestinal epithelial cell protective activity. The present work provides experimental evidence for elucidating the pharmaceutical components of SJZD and presents an effective strategy for the research of oligosaccharides in traditional Chinese medicine (TCM). [ABSTRACT FROM AUTHOR]

The viscosity of CaO–SiO2–FeOt–Al2O3–BaO steel slag with the BaO substitution for CaO is measured. Calculation of the corrected optical basicity and the apparent activation energy of the steel slag are executed. The effect of substituting CaO with BaO on structure evolution is studied. The measured results show that the viscosity of molten slag increases with the BaO substitution. The values of corrected optical basicity decrease from 0.63441 to 0.62329 with the BaO substitution. The apparent activation energy shows an upward trend from 152.78 to 160.62 kJ mol−1 with the BaO substitution. The Fourier transform infrared reflection analysis indicates that the structure complexity of the [SiO4] and [AlO4] tetrahedrons is increased with the BaO substitution. The Raman analysis indicates that the translation of Q0 and Q1 to Q2 and Q3 is advanced with the substitution of BaO for CaO in molten slag. The conversion of O2− to O0 is promoted with the substitution of BaO for CaO using X‐Ray photoelectron spectrometer analysis. The complexity of the molten slag network structure and the degree of polymerization are all increased by the substitution of BaO for CaO, which sits comfortably with measured viscosity results. [ABSTRACT FROM AUTHOR]

An accurate characterization of the fine molecular structure of starch in terms of the chain length distribution (CLD) of amylopectin requires complete dispersion of the starch in a solvent, either buffer or water and the non-interference of this on the subsequent enzymatic debranching of starch with isoamylase (pretreatments before determining the CLD). In this study, the HYLON V and HYLON VII starches (commercial high-amylose corn starches) were selected, since high-amylose starches typically present difficulties in their dispersion and, therefore, the study of their fine structure can commonly present errors. The goal of this research was to study two water dispersion treatments (1. boiling water for 1 h and 2. autoclaving at 120 °C and 15 Psi for 15 min) to achieve a fast and reliable method of the fine structure of two high-amylose corn starches using high-performance size exclusion chromatography coupled with a refractive index detector (HPSEC-RID) and high-performance anion-exchange chromatography coupled a pulsed amperometric detector (HPAEC-PAD). The HPSEC-RID chromatograms of both starches showed better resolution using autoclaving than boiling water treatment. The two starches tested had higher amylose and degree of polymerization (DP) values utilizing the autoclaving than the boiling water treatment. However, no appreciable differences were observed in the CLD values employing HPAEC-PAD for either of the two water dispersion treatments. Lastly, the water dispersion treatment by autoclaving before enzymatic debranching is recommended to obtain a more accurate quantification of the amylose content of high-amylose starches. [ABSTRACT FROM AUTHOR]

Introduction: Humus can be formed during composting through biological pathways, nonetheless, the mechanisms through which bacterial and fungal communities govern the development of humus in compost with the addition of biochar remain uncertain. Methods: In this study, compost with cow dung and maize stover as feedstock was employed as a control group, and compost with 10% biochar added on top of the feedstock was adopted as a treatment group to investigate the effect of bacterial and fungal communities on humus formation during biochar composting. Results and Discussion: The results demonstrated that the humic acid content increased by 24.82 and 25.10% at the cooling and maturation stages, respectively, after adding biochar. Besides, the degree of polymerization content in the maturation stage was elevated by 90.98%, which accelerated the humification process of the compost. During the thermophilic and maturity stages, there was a respective increase of 51.34 and 31.40% in reducing sugar content, suggesting that the inclusion of biochar could furnish ample reducing sugar substrate for the Maillard reaction. The addition of biochar reduced the number of humus precursorassociated genera by 35, increased the number of genera involved in humus synthesis by two, and enhanced the stability of the cross-domain network between bacteria and fungi, which confirms that microorganisms contribute to the humification process by decreasing humus precursor consumption as well as increasing humus synthesis with the addition of biochar. Additionally, adding biochar could enhance the humification capacity of the compost pile by dominating the Maillard reaction with reducing sugars as the substrate and strengthening the function of humus synthesis-associated genera. This study enhances our comprehension of the regulatory pathways of biochar in the humification process during composting. [ABSTRACT FROM AUTHOR]

This study investigated the impact of BaO/Al2O3 molar ratio on the electrical conductivity and Al coordination state of CaO–MgO–SiO2–Al2O3–BaO slag using four-electrode technique and 27Al MAS-NMR spectroscopy, respectively. With an increasing BaO/Al2O3 molar ratio from 0.14 to 0.36, BaO preferentially participated in charge compensation of Al3+, which facilitated the transition from AlO5 and AlO6 structures to AlO4 structure and increased the stability of AlO4 tetrahedra, thus enhancing the slag's polymerization and reducing its electrical conductivity. However, once the compensation achieved equilibrium, remaining BaO was involved in depolymerizing the tetrahedral structure and promoting the formation of AlO5 and AlO6 structures. Consequently, the decreased degree of polymerization and increased concentration of free ions together led to an increase in electrical conductivity. However, the increased migration resistance due to the large radius of Ba2+ ion is responsible for the electrical conductivity minimum near the molar ratio of 0.43. [ABSTRACT FROM AUTHOR]

As high-value chitosan derivatives, chitooligosaccharides (COSs) with biodegradable, biocompatible, nontoxic, antimicrobial, and antioxidant activities have been widely applied in food-related fields. Chitosanases can hydrolyze chitosan to produce COSs. Herein, a chitosanase (LeCho1) from Lentinula edodes was successfully expressed in Escherichia coli and was then purified and characterized. LeCho1 had a low sequence identity with other chitosanases reported from the GH75 family. The recombinant protein showed a molecular mass of 27 kDa on SDS-PAGE. LeCho1 preferentially hydrolyzed chitosan with a high degree of deacetylation (DDA) and exhibited maximal activity (71.88 U/mg) towards 95% DDA chitosan at pH 3.0 and 50 °C. It possessed good stability at pH 2.0–6.0 and temperatures below 45 °C. Its hydrolytic activity was remarkably enhanced by the metal ion Mn2+ at 1 mM, while it was totally inhibited by 1 mM Fe3+ or 10 mM EDTA. Its Km and Vmax values were 0.04 μM and 76.81 μmol·min−1·mg−1, respectively, indicating good substrate affinity. LeCho1 degraded chitosan into COSs with degrees of polymerization (DPs) of 2–5, while it had no action on COSs with DPs of less than 5, revealing its endo-chitosanase activity. This study proved that chitosanase LeCho1 is a promising candidate in the industrial preparation of COSs due to its excellent properties. [ABSTRACT FROM AUTHOR]

AbstractThere have been studies published on the composition and coating uses of raw lacquers following enzymatic oxidative polymerization. The change of urushiol’ thermal stability and biological activity following polymerization to create oligomer, however, has received little attention. This work using silica gel column chromatography to separate urushiol and urushiol oligomer from polymerized raw lacquer and assessed its antibacterial, antioxidant, and thermal stability in an effort to decrease the allergenicity of urushiol and increase its application. By using gel chromatography, the urushiol oligomer were discovered to be polymers with 2–5 degrees of polymerization. According to characterization results from techniques like UV, FT-IR, and 1H NMR, urushiol was converted into urushiol oligomer by addition reactions, and C–C coupling. The findings demonstrated that the urushiol oligomer’ IC50 values for scavenging DPPH and ABTS free radicals were 40.8 and 27.4 μg/mL, respectively, and that their minimum inhibitory concentrations against Staphylococcus aureus and Staphylococcus epidermidis were 250 and 125 μg/mL. The urushiol oligomer’s thermogravimetric differential curve peak temperature (461.8 °C) was higher than urushiol’s (239.5 °C), indicating that urushiol undergoes polymerization with enhanced thermal stability. The study’s findings establish a foundation for the use of polymerized urushiol and urushiol oligomer in applications including functional materials and additives. [ABSTRACT FROM AUTHOR]

Porous frameworks with controlled pore structure and tunable aperture are greatly demanded. However, precise synthesis of this kind of materials is a formidable challenge. Herein, we report the fabrication of two‐dimensional (2D) supramolecular polymer frameworks using a precisely synthesized rod‐like helical polyisocyanide as link. Four three‐arm star‐shaped polyisocyanides with the degree of the polymerization of 10, 20, 30 and 40, and having 2‐ureido‐4[1H]‐pyrimidinone (UPy) terminals were synthesized. 2D‐Crystalline polymer frameworks with apertures of 5.3, 10.1, 13.9, and 19.1 nm were respectively obtained through intermolecular hydrogen bonding interaction between the terminal Upy units. The pore aperture is dependent on the length of polyisocyanide backbone. Thus, well‐defined supramolecular polymer frameworks with controlled and uniform hexagonal pores were obtained, as proved by small‐angle X‐ray scattering (synchrotron radiation facility), atomic force microscopy, and Brunauer–Emmett–Teller analyses. The frameworks with uniform large pore aperture were used to purify nanomaterials and immobilize biomacromolecules. For instance, the membranes of the polymer frameworks could size‐fractionation of silver nanoparticles into uniform nanoparticles with very low dispersity. The frameworks with large aperture facilitated the inclusion of myoglobin and enhanced the stability and catalytic activity. [ABSTRACT FROM AUTHOR]

Förster resonance energy transfer (FRET) is an established tool for measuring distances between two molecules (donor and acceptor) on the nanometer scale. In the field of polymer science, the use of FRET to measure polymer end‐to‐end distances (Ree) often requires complex synthetic steps to label the chain ends with the FRET pair. This work reports an anthracene‐functionalized chain‐transfer agent for reversible addition‐fragmentation chain‐transfer (RAFT) polymerization, enabling the synthesized chains to be directly end‐labeled with a donor and acceptor without the need for any post‐polymerization functionalization. Noteworthily, this FRET method allows for chain conformation measurements of low molecular weight oligomers in situ, without any work‐up steps. Using FRET to directly measure the average Ree of the oligomer chains during polymerization, the chain growth of methyl methacrylate, styrene, and methyl acrylate is investigated as a function of reaction time, including determining their degree of polymerization (DP). It is found that DP results from FRET are consistent with other established measurement methods, such as nuclear magnetic resonance (NMR) spectroscopy. Altogether, this work presents a broadly applicable and straightforward method to in situ characterize Ree of low molecular weight oligomers and their DP during reaction. [ABSTRACT FROM AUTHOR]

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]

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 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 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 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 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]

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 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]

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]

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]